阅读说明：本技术 正极活性物质、其制备方法及包含其的锂二次电池 (Positive active material, preparation method and the lithium secondary battery comprising it ) 是由 宣良国 金云赫 于 2018-04-13 设计创作，主要内容包括：本发明提供正极活性物质。在上述正极活性物质中,镍为60摩尔百分比以上,包含锂及添加金属,具有第一结晶结构,上述第一结晶结构沿着c轴方向具有固有的晶格常数,在充放电过程中,生成第二结晶结构及第三结晶结构,上述第二结晶结构具有沿着c轴方向长于上述第一结晶结构的晶格常数,上述第三结晶结构具有沿着c轴方向短于上述第一结晶结构的晶格常数,通过上述添加金属,减少在充放电过程中生成的上述第二结晶结构及上述第三结晶结构的生成比率的变化量。(The present invention provides positive active material.In above-mentioned positive active material, nickel is 60 molar percentages or more, include lithium and addition metal, with the first crystalline texture, above-mentioned first crystalline texture has intrinsic lattice constant along c-axis direction, in charge and discharge process, generate the second crystalline texture and third crystalline texture, above-mentioned second crystalline texture has the lattice constant for being longer than above-mentioned first crystalline texture along c-axis direction, above-mentioned third crystalline texture has the lattice constant for being shorter than above-mentioned first crystalline texture along c-axis direction, pass through above-mentioned addition metal, reduce the variable quantity of the generation ratio of above-mentioned second crystalline texture and above-mentioned third crystalline texture that generate in charge and discharge process.)

1. a kind of positive active material, which is characterized in that

Nickel is 60 molar percentages or more, comprising lithium and adds metal,

With the first crystalline texture, above-mentioned first crystalline texture has intrinsic lattice constant along c-axis direction,

In charge and discharge process, the second crystalline texture and third crystalline texture are generated, above-mentioned second crystalline texture has along c-axis Direction is longer than the lattice constant of above-mentioned first crystalline texture, and above-mentioned third crystalline texture, which has, is shorter than above-mentioned the along c-axis direction The lattice constant of one crystalline texture,

By above-mentioned addition metal, above-mentioned second crystalline texture generated in charge and discharge process and above-mentioned third crystallization knot are reduced The variable quantity of the generation ratio of structure.

2. positive active material according to claim 1, which is characterized in that in the differential capacitance inspection based on charge and discharge number In mapping table, in the case where charge and discharge number is 100 times, in the range of 4.1~4.3V, the reduction amount of integral area is 10% or less.

3. positive active material according to claim 1, which is characterized in that above-mentioned addition metal include zirconium, titanium, aluminium, tungsten, At least one of molybdenum, niobium, tantalum, bismuth, ruthenium, magnesium, zinc, gallium, vanadium, chromium, calcium, strontium or tin.

4. positive active material according to claim 1, which is characterized in that

Above-mentioned addition metal includes titanium,

Above-mentioned addition metal is less than 3 molar percentages.

5. positive active material according to claim 1, which is characterized in that

Above-mentioned addition metal includes zirconium,

Above-mentioned addition metal is less than 2 molar percentages.

6. positive active material according to claim 1, which is characterized in that

Above-mentioned addition metal includes aluminium,

Above-mentioned addition metal is less than 2 molar percentages.

7. positive active material according to claim 1, which is characterized in that above-mentioned first crystalline texture is trigonal system knot Crystal structure.

8. positive active material according to claim 1, which is characterized in that above-mentioned addition metal has uniform in particle Concentration.

9. a kind of positive active material, which is characterized in that

Nickel is 60 molar percentages or more, comprising lithium and adds metal,

With the first crystalline texture, above-mentioned first crystalline texture has intrinsic lattice constant along c-axis direction,

In charge and discharge process, the second crystalline texture and third crystalline texture are generated, above-mentioned second crystalline texture has along c-axis Direction is longer than the lattice constant of above-mentioned first crystalline texture, and above-mentioned third crystalline texture, which has, is shorter than above-mentioned the along c-axis direction The lattice constant of one crystalline texture,

According to the concentration of above-mentioned nickel concentration and above-mentioned addition metal, the above-mentioned second crystallization knot generated in charge and discharge process is controlled The variable quantity of the generation ratio of structure and above-mentioned third crystalline texture, to control charge/discharge capacity in the range of 4.1~4.3V.

10. positive active material according to claim 9, which is characterized in that

Offspring comprising agglomerating multiple primary particles,

Above-mentioned multiple primary particles extend along the direction radiated from the center of above-mentioned offspring.

11. a kind of lithium secondary battery characterized by comprising

Anode includes positive active material described in any one of claims 1 to 10；

Cathode is separated with above-mentioned anode；And

Electrolyte is located between above-mentioned anode and above-mentioned cathode.

12. a kind of preparation method of positive active material characterized by comprising

The step of preparation includes the positive active material precursor of at least one of nickel, cobalt, manganese or aluminium；

Mixing includes the step of adding the addition source metal and above-mentioned positive active material precursor of metal；And

The step of above-mentioned positive active material precursor and above-mentioned addition source metal, lithium salts to mixing are fired.

13. the preparation method of positive active material according to claim 12, which is characterized in that

Above-mentioned positive active material precursor includes nickel,

Nickel is 60 molar percentages or more.

14. the preparation method of positive active material according to claim 12, which is characterized in that mixing it is above-mentioned just It further include the above-mentioned positive electrode active material to mixing before pole active substance precursors and above-mentioned addition source metal, lithium salts are fired The step of matter precursor and above-mentioned addition source metal, above-mentioned lithium salts are mixed.

15. the preparation method of positive active material according to claim 12, which is characterized in that above-mentioned addition source metal with The hydroxide form of the oxide of above-mentioned addition metal and above-mentioned addition metal provides.

Technical field

This application involves positive active material, preparation method and include its lithium secondary battery.

Background technique

With such as smart phone, MP3 player, tablet computer Portable mobile electronic device development, to can deposit The demand of the secondary cell of storage energy sharply increases.In particular, with electric car, medium-and-large-sized energy storage system and needs are released The demand of the portable equipment of energy resource density, lithium secondary battery gradually increases.

Due to the increase of the demand of lithium secondary battery, the positive active material that research and development are used for lithium secondary battery is being studied. For example, being disclosed in Korean Patent Publication bulletin 10-2014-0119621 (application number 10-2013-0150315) a kind of secondary Battery, using comprising nickel, manganese, cobalt lithium excess positive active material preparation precursor, adjust in the substituted metal of precursor Type and composition adjust type and the additive amount of the metal of addition to have the characteristic of high capacity and long-life.

Summary of the invention

Technical problem

The technical purpose to be realized of the application is, provides positive active material, the preparation method of high reliability And the lithium secondary battery comprising it.

The another technical purpose to be realized of the application is, provides positive active material, the preparation method of high capacity And the lithium secondary battery comprising it.

Another technical purpose to be realized of the application is, provides positive active material, the preparation method of long-life And the lithium secondary battery comprising it.

What the application to be realized is there are also a technical purpose, provides the positive electrode active material that thermal stability is improved Matter, preparation method and the lithium secondary battery comprising it.

The another technical purpose to be realized of the application is, makes being prepared by the positive active material comprising nickel for high concentration Lithium secondary battery life characteristic reduce minimize.

The another technical purpose to be realized of the application is, provides positive active material for electric vehicle, its preparation side Method and lithium secondary battery comprising it.

The application technical purpose to be solved is not limited thereto.

Technical solution

In order to achieve the above technical purposes, the application provides positive active material.

According to an embodiment, in above-mentioned positive active material, nickel is 60 molar percentages or more, includes lithium and addition gold Belong to, there is the first crystalline texture, above-mentioned first crystalline texture has intrinsic lattice constant along c-axis direction, in charge and discharge Cheng Zhong, generates the second crystalline texture and third crystalline texture, and above-mentioned second crystalline texture, which has, is longer than above-mentioned the along c-axis direction The lattice constant of one crystalline texture, above-mentioned third crystalline texture have the crystalline substance for being shorter than above-mentioned first crystalline texture along c-axis direction Lattice constant reduces above-mentioned second crystalline texture generated in charge and discharge process and above-mentioned third knot by above-mentioned addition metal The variable quantity of the generation ratio of crystal structure.

According to an embodiment, in differential capacitance (the Differential capacity: differential electricity based on charge and discharge number Hold) it detects in chart, in the case where charge and discharge number is 100 times, in the range of 4.1~4.3V, the reduction of integral area Amount is 10% or less.

According to an embodiment, above-mentioned addition metal include zirconium, titanium, aluminium, tungsten, molybdenum, niobium, tantalum, bismuth, ruthenium, magnesium, zinc, gallium, vanadium, At least one of chromium, calcium, strontium or tin.

According to an embodiment, above-mentioned addition metal includes titanium, and above-mentioned addition metal is less than 3 molar percentages.

According to an embodiment, above-mentioned addition metal includes zirconium, and above-mentioned addition metal is less than 2 molar percentages.

According to an embodiment, above-mentioned addition metal includes aluminium, and above-mentioned addition metal is less than 2 molar percentages.

According to an embodiment, above-mentioned first crystalline texture is trigonal system crystalline texture.

According to an embodiment, above-mentioned addition metal has uniform concentration in particle.

According to an embodiment, in above-mentioned positive active material, nickel is 60 molar percentages or more, includes lithium and addition gold Belong to, there is the first crystalline texture, above-mentioned first crystalline texture has intrinsic lattice constant along c-axis direction, in charge and discharge Cheng Zhong, generates the second crystalline texture and third crystalline texture, and above-mentioned second crystalline texture, which has, is longer than above-mentioned the along c-axis direction The lattice constant of one crystalline texture, above-mentioned third crystalline texture have the crystalline substance for being shorter than above-mentioned first crystalline texture along c-axis direction Lattice constant controls above-mentioned second knot generated in charge and discharge process according to the concentration of above-mentioned nickel concentration and above-mentioned addition metal The variable quantity of the generation ratio of crystal structure and above-mentioned third crystalline texture controls charge and discharge capacitor in the range of 4.1~4.3V Amount.

According to an embodiment, in above-mentioned positive active material, the offspring comprising agglomerating multiple primary particles is above-mentioned Multiple primary particles extend along the direction radiated from the center of above-mentioned offspring.

In order to achieve the above technical purposes, the application provides lithium secondary battery.

According to an embodiment, above-mentioned lithium secondary battery includes: anode, includes positive electrode active material described in above-described embodiment Matter；Cathode is separated with above-mentioned anode；And electrolyte, it is located between above-mentioned anode and above-mentioned cathode.

In order to achieve the above technical purposes, the application provides the preparation method of positive active material.

According to an embodiment, the preparation method of above-mentioned positive active material includes: preparation comprising in nickel, cobalt, manganese or aluminium The step of at least one positive active material precursor；Addition source metal of the mixing comprising addition metal and above-mentioned positive electrode active material The step of matter precursor；And the above-mentioned positive active material precursor and above-mentioned addition source metal, lithium salts of mixing are fired Step.

According to an embodiment, above-mentioned positive active material precursor includes nickel, and nickel is 60 molar percentages or more.

According to an embodiment, in the preparation method of above-mentioned positive active material, in the above-mentioned positive electrode active material to mixing Before matter precursor and above-mentioned addition source metal, lithium salts are fired, further include to the above-mentioned positive active material precursor of mixing and The step of above-mentioned addition source metal, above-mentioned lithium salts are mixed.

According to an embodiment, above-mentioned addition source metal is with the oxide of above-mentioned addition metal and the hydrogen-oxygen of above-mentioned addition metal Compound form provides.

Technical effect

In the positive active material of the embodiment of the present invention, it may include the high concentration of nickel of 60 molar percentages or more, can have There is the first crystalline texture, above-mentioned first crystalline texture has intrinsic lattice constant along c-axis direction.Living comprising above-mentioned anode Property substance lithium secondary battery charge and discharge process in, above-mentioned positive active material generate the second crystalline texture and third crystallization Structure, above-mentioned second crystalline texture have the lattice constant for being longer than above-mentioned first crystalline texture along c-axis direction, above-mentioned third knot Crystal structure has the lattice constant for being shorter than above-mentioned first crystalline texture along c-axis direction, and by above-mentioned addition metal, reduction is being filled The variable quantity of the generation ratio of above-mentioned second crystalline texture and above-mentioned third crystalline texture that are generated in discharge process.

Therefore, it is possible to provide improve charge/discharge capacity and the lithium secondary battery with the long-life.

Detailed description of the invention

Fig. 1 is the figure for illustrating the positive active material of the embodiment of the present invention；

Fig. 2 is used to illustrate to be contained in the primary particle of the positive active material of the embodiment of the present invention, shows the A- along Fig. 1 The section of B interception；

Fig. 3 is that the energy disperse spectroscopy (EDS) of the positive active material precursor of 1-2 of the embodiment of the present invention maps data；

Fig. 4 is that the energy disperse spectroscopy of the positive active material precursor of comparative example 2 of the present invention maps data；

Fig. 5 is scanning electron microscope (SEM) photo of the positive active material precursor of 1-2 of the embodiment of the present invention；

Fig. 6 is the electron scanning micrograph of the positive active material precursor of comparative example 2 of the present invention；

Fig. 7 is that the energy disperse spectroscopy of the positive active material precursor of comparative example 2 of the present invention maps data and scanning electron microscope Photo；

Fig. 8 is the service life of the lithium secondary battery of positive active material of the detection comprising 1-2 of the embodiment of the present invention and comparative example 2 The chart of characteristic；

Fig. 9 is lithium two of the detection comprising 1-1 of the embodiment of the present invention to embodiment 1-4 and the positive active material of comparative example 1 The chart of the capacity characteristic of primary cell；

Figure 10 is lithium two of the detection comprising 1-1 of the embodiment of the present invention to embodiment 1-4 and the positive active material of comparative example 1 The chart of the life characteristic of primary cell；

Figure 11 to Figure 15 is positive active material of the detection comprising comparative example 1 of the present invention and embodiment 1-1 to embodiment 1-4 Lithium secondary battery differential capacitance chart；

Figure 16 is for illustrating according to the positive electrode active material comprising comparative example 1 of the present invention and embodiment 1-1 to embodiment 1-4 The chart of the volume change of the charge and discharge number of the lithium secondary battery of matter；

Figure 17 is lithium two of the detection comprising 2-1 of the embodiment of the present invention to embodiment 2-3 and the positive active material of comparative example 1 The chart of the capacity characteristic of primary cell；

Figure 18 is lithium two of the detection comprising 2-1 of the embodiment of the present invention to embodiment 2-3 and the positive active material of comparative example 1 The chart of the life characteristic of primary cell；

Figure 19 to Figure 21 is that the lithium of positive active material of the detection comprising 2-1 of the embodiment of the present invention to embodiment 2-3 is secondary The chart of the differential capacitance of battery；

Figure 22 to Figure 24 is the scanning electricity for shooting the section of positive active material of 2-2 of the embodiment of the present invention and comparative example 1 Sub- microscope photo；

Figure 25 is the chart for detecting the sheet resistance of positive active material of 2-2 of the embodiment of the present invention；

Figure 26 is the chart for detecting the sheet resistance of positive active material of comparative example 1 of the present invention；

Figure 27 is the chart for comparing the Rct value of positive active material of 2-2 of the embodiment of the present invention and comparative example 1；

Figure 28 is the thermal stability for detecting the positive active material of 2-1 of the embodiment of the present invention, embodiment 2-2 and comparative example 1 Chart；

Figure 29 is lithium two of the detection comprising 3-1 of the embodiment of the present invention to embodiment 3-3 and the positive active material of comparative example 3 The chart of the capacity characteristic of primary cell；

Figure 30 is lithium two of the detection comprising 3-1 of the embodiment of the present invention to embodiment 3-3 and the positive active material of comparative example 3 The chart of the life characteristic of primary cell；

Figure 31 to Figure 35 is positive active material of the detection comprising comparative example 3 of the present invention, embodiment 3-1 to embodiment 3-4 Lithium secondary battery differential capacitance chart；

Figure 36 to Figure 39 is the table of detection comparative example 3 of the present invention, positive active material of the embodiment 3-1 to embodiment 3-3 The chart of surface resistance；

Figure 40 be detection comparative example 3 of the present invention, embodiment 3-1 and embodiment 3-3 positive active material thermal stability Chart；

Figure 41 is that detection includes comparative example 1 of the present invention, embodiment 1-1, embodiment 1-2, embodiment 2-2 and embodiment 3-4 Positive active material lithium secondary battery capacity characteristic chart；

Figure 42 is that detection includes comparative example 1 of the invention, embodiment 1-1, embodiment 1-2, embodiment 2-2 and embodiment 3- The chart of the life characteristic of the lithium secondary battery of 4 positive active material；

Figure 43 and Figure 44 Wesy includes comparative example 1 of the present invention, embodiment 1-1, embodiment 1-2, embodiment in explanation basis The chart of the volume change of the charge and discharge number of the lithium secondary battery of the positive active material of 2-2 and embodiment 3-4；

Figure 45 is the positive active material of detection comparative example 1 of the present invention, embodiment 1-1 to embodiment 1-4 and embodiment 2-2 Particle intensity chart；

Figure 46 to Figure 49 is the differential capacitance for illustrating the variable quantity of the H2 and H3 phase (phase) according to the content of nickel Chart；

Figure 50 is the appearance for illustrating the charge and discharge number of the lithium secondary battery according to the positive active material using Figure 47 Measure the chart of variation；

Figure 51 is the service life according to the lithium secondary battery of positive active material of the nickel concentration detection comprising the embodiment of the present invention The chart of characteristic；

Figure 52 is the block diagram for showing the electric car of one embodiment of the invention；

Figure 53 is the perspective view of the electric car of one embodiment of the invention；

Figure 54 is the figure for illustrating the battery pack of one embodiment of the invention.

Specific embodiment

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.But technical idea of the invention is not limited to In embodiment described herein, other forms can be embodied as.Instead, the embodiment introduced herein becomes revealed content More comprehensively and completely, and those of ordinary skill is made adequately to understand thought of the invention.

In the present specification, when referring to that a structural element is located on another structural element, it is meant that can be formed directly in In intervening other structures element on another structural element or between them.Also, in the accompanying drawings, in order to effectively illustrate in technology Hold, the thickness in film and region is exaggerated.

Also, in the various embodiments of this specification, the first, second, third, etc. term is wanted for describing various structures Element, but these structural elements are not limited to these terms.These terms are only used to distinguish a structural element and another structure Element.Therefore, the first structure element referred in one embodiment can be the second structural element referred in another embodiment. The each embodiment for illustrating and illustrating herein further includes its complementary embodiment.Also, the "and/or" in this specification means At least one of the structural element enumerated including front and back.

In the description, unless explicitly indicating that difference on context, then singular expression includes the expression of plural number.Also, It should be understood that the term of " comprising " or " having " etc. is for specifying the feature recorded on specification, number, step, knot The presence of structure element or their combination, rather than other one or more features of exclusion or number, step, structure are wanted The presence or additional possibility of element or their combination.

It is related with related known function or structure when being judged as also, during illustrating the present invention in the following Illustrate when unnecessarily obscuring purport of the invention, will description is omitted.

Also, in the present specification, crystallographic system (crystal system) can be by anorthic system (triclinic), monoclinic crystal It is (monoclinic), orthorhombic system (orthorhombic), tetragonal system (tetragonal), trigonal system (trigonal Or rhombohedral), hexagonal crystal system (hexagonal) and cubic system (cubic) 7 composition.

Also, in the present specification, " molar percentage " means assuming that positive active material or positive active material The sum of the residual metallic in addition to lithium and oxygen in precursor for 100% in the case where be contained in positive active material or anode is living The content of any metal of property precursors.

Also, in the present specification, " charge/discharge capacity is controlled in particular range " means to include respective specific model Charge/discharge capacity is controlled in the range of enclosing, and is not meant to be confined to control charge/discharge capacity within the scope of respective specific.

Fig. 1 is the figure for illustrating the positive active material of the embodiment of the present invention, and Fig. 2 is of the invention real for illustrating to be included in The primary particle for applying the positive active material of example shows the section of the A-B interception along Fig. 1.

Referring to Fig.1, the positive active material 100 of the embodiment of the present invention may include nickel.Above-mentioned positive active material 100 removes nickel Except, it may include at least one of cobalt, manganese or aluminium, may include lithium and addition metal.In other words, above-mentioned positive active material can Think comprising at least one of cobalt, manganese or aluminium, nickel, lithium and the oxide for adding metal.

For example, above-mentioned addition metal may include at least one of zirconium, titanium or aluminium.Alternatively, as an example, above-mentioned addition are golden again Category may include at least one of tungsten, molybdenum, niobium, tantalum, bismuth, ruthenium, magnesium, zinc, gallium, vanadium, chromium, calcium, strontium or tin.

For example, above-mentioned positive active material 100 can be the metal oxide comprising nickel, lithium, above-mentioned addition metal and oxygen. Alternatively, as an example, above-mentioned positive active material 100 can be the metal oxygen comprising nickel, cobalt, lithium, above-mentioned addition metal and oxygen again Compound.Alternatively, as an example, above-mentioned positive active material 100 can be to include nickel, cobalt, manganese, lithium, above-mentioned addition metal and oxygen again Metal oxide.Alternatively, above-mentioned positive active material 100 can be to include nickel, cobalt, aluminium, lithium, above-mentioned addition such as another example The metal oxide of metal and oxygen.The technical idea of the embodiment of the present invention is applicable to the positive electrode active material comprising various substances Matter.

According to an embodiment, above-mentioned positive active material 100 may include the nickel of 60 molar percentages or more.

According to an embodiment, above-mentioned addition metal can be provided in the form of oxide or hydroxide.For example, above-mentioned addition Metal may include at least one of titanium oxide, aluminum oxide, aluminium hydroxide or Zirconium oxide.

According to an embodiment, above-mentioned addition metal can have the equal of substance in above-mentioned 100 particle of positive active material Even concentration.In other words, as described later, even if by mixing addition source metal and positive electrode active material comprising above-mentioned addition metal The method of matter precursor prepares above-mentioned positive active material 100, and above-mentioned addition metal can also be in above-mentioned 100 particle of positive active material Inside substantially it is evenly distributed.

According to an embodiment, at least one of nickel, cobalt, manganese or aluminium concentration can be real in above-mentioned positive active material 100 Matter it is constant.Alternatively, according to another embodiment, in above-mentioned positive active material 100, in nickel, cobalt, manganese or aluminium at least one Kind concentration can have concentration gradient or above-mentioned from the center of particle to the surface direction of above-mentioned particle in entire above-mentioned particle A part of particle has concentration gradient.Alternatively, according to another embodiment, above-mentioned positive active material 100 can include: core； And shell portion, the concentration of metal (at least one of nickel, cobalt, manganese or aluminium) are different from above-mentioned core.The skill of the embodiment of the present invention Art thought is applicable to the positive active material of various structures and form.

According to an embodiment, above-mentioned positive active material 100 can be indicated by following chemical formula 1.

Chemical formula 1

LiNi_aM1_bM2_cM3_dO₂

In above-mentioned chemical formula 1, M1, M2, M3 are 0.5≤a < 1,0≤b < 1 selected from one of cobalt, manganese or aluminium, 0≤c < 1,0 < d≤0.01, M1, M2 and M3 can be mutually different metal.

In above-mentioned chemical formula 1, M3 can be above-mentioned addition metal.

Above-mentioned positive active material 100 may include: multiple primary particles 30；And offspring, cohesion above-mentioned multiple one Secondary particle 30.

Above-mentioned multiple primary particles 30 can be in the region inside above-mentioned offspring towards the surface of above-mentioned offspring The direction of 20 radiation (radiate) extends.A region inside above-mentioned offspring can be the center 10 of above-mentioned offspring. In other words, above-mentioned primary particle 30 can be the above-mentioned region inside above-mentioned offspring to the above-mentioned of above-mentioned offspring Rod-shaped (rod shape) form that surface 20 extends.

It can be between above-mentioned above-mentioned multiple primary particles 30 in rod state, in other words, in the above-mentioned of above-mentioned offspring Between above-mentioned multiple primary particles 30 that central part 10 extends to above-mentioned 20 direction D of surface element provide metal ion (for example, lithium from Son) and electrolyte movement routine.Therefore, the charge and discharge effect of secondary cell can be improved in the positive active material of the embodiment of the present invention Rate.

According to an embodiment, compared to the above-mentioned primary particle at the above-mentioned center 10 inside the above-mentioned offspring of relative proximity 30, the above-mentioned primary particle 30 on the above-mentioned surface 20 of the above-mentioned offspring of relative proximity can be along inside above-mentioned offspring Above-mentioned center 10 has longer length to the direction on the above-mentioned surface 20 of above-mentioned offspring.In other words, from above-mentioned secondary At least part for the above-mentioned offspring that the above-mentioned center 10 of particle extends to above-mentioned surface 20, above-mentioned multiple primary particles 30 Length more adjacent to the above-mentioned surface 20 of above-mentioned offspring more increase.

According to an embodiment, above-mentioned positive active material 100 can have trigonal system (trigonal or Rhombohedral) crystalline texture.The crystalline texture of above-mentioned positive active material 100 can have a axis and c-axis.Above-mentioned anode is living Property substance 100 can along c-axis direction have intrinsic lattice constant (lattice constant).

In the charge and discharge process of the lithium secondary battery comprising above-mentioned positive active material 100, it can increase along c-axis direction Or reduce intrinsic lattice constant.In other words, in the case where above-mentioned positive active material 100 has the first crystalline texture, on State the lattice constant that the first crystalline texture has the first intrinsic length along c-axis direction, produce the second crystalline texture and/or Third crystalline texture, above-mentioned second crystalline texture, which has, is longer than the second length of above-mentioned first length along c-axis direction, and above-mentioned the Three crystalline textures have the third length for being shorter than above-mentioned first length along c-axis direction.Along the increasing of the lattice constant in c-axis direction Add and reduce the volume that can change above-mentioned positive active material 100 significantly.Therefore, lattice constant along c-axis direction increase or The generation ratio of above-mentioned second crystalline texture and above-mentioned third crystalline texture that reduce is non-constant and is reduced according to charge and discharge number Or in increased situation, the life characteristic of secondary cell can be significantly reduced.In particular, in order to improve the capacity of lithium secondary battery and In the case where preparing above-mentioned positive active material 100 in a manner of the nickel comprising high concentration (for example, more than 60 molar percentages), The generation ratio of above-mentioned second crystalline texture and above-mentioned third crystalline texture can be substantially reduced according to charge and discharge number, therefore, lithium The life characteristic of secondary cell can significantly reduce.

But the above-mentioned positive active material 100 of the embodiment of the present invention, which can be such that lattice constant increases along c-axis direction, to add deduct The crystalline texture that the substantive constant maintenance of the generation ratio of few crystalline texture or lattice constant are increased or decreased along c-axis direction Generation ratio variation minimize.In other words, make with the side of the nickel comprising high concentration (for example, more than 60 molar percentages) Formula prepares above-mentioned positive active material 100, can also prevent by the inclusion of the above-mentioned addition metal in above-mentioned positive active material 100 The generation ratio of above-mentioned second crystalline texture and above-mentioned third crystalline texture is substantially reduced according to charge and discharge number.Therefore, it can mention For with high capacity and long-life characteristics positive active material, include its lithium secondary battery.

Hereinafter, illustrating the preparation method of the positive active material of the embodiment of the present invention.

Prepare the bottom liquid comprising at least one of nickel, cobalt, manganese or aluminium.In the case where above-mentioned bottom liquid includes nickel, for example, Above-mentioned bottom liquid can be nickel sulfate.In the case where above-mentioned bottom liquid includes cobalt, for example, above-mentioned bottom liquid can be cobaltous sulfate.Upper Bottom liquid is stated comprising in the case where manganese, above-mentioned bottom liquid can be manganese sulfate.It include multiple in nickel, cobalt, manganese or aluminium in above-mentioned bottom liquid In the case where metal, above-mentioned bottom liquid may include multiple aqueous metal salts.

Above-mentioned bottom liquid can be provided to above-mentioned functional group to prepare the positive active material precursor comprising metal hydroxides, on Stating metal hydroxides includes at least one of nickel, cobalt, manganese or aluminium.In addition to above-mentioned bottom liquid, it can also be mentioned to above-mentioned functional group For ammonia solution.

It is ready for the addition source metal comprising addition metal.According to an embodiment, above-mentioned addition source metal can be above-mentioned Add the oxide of metal or the hydroxide of above-mentioned addition metal.Can by the above-mentioned addition source metal of physical mixed and it is above-mentioned just Pole active substance precursors (for example, ball milling (Ball mill), hand mix (hand mix)) adulterate above-mentioned addition metal to prepare Positive active material precursor.Above-mentioned addition metal can be to be coated on above-mentioned positive active material precursor, in other words, above-mentioned gold The state for belonging to hydroxide provides.

It can be prepared just by being fired to the above-mentioned positive active material precursor and lithium salts of adulterating above-mentioned addition metal Pole active material, above-mentioned positive active material includes at least one of nickel, cobalt, manganese or aluminium and lithium, and includes that doping is above-mentioned and add Add the metal oxide of metal.

According to an embodiment, mix above-mentioned positive active material precursor and above-mentioned addition source metal, later, can with mix State the above-mentioned positive active material precursor and the mixing of above-mentioned addition source metal of lithium salts.It is therefore possible to prevent above-mentioned addition source metal is first It is reacted with above-mentioned lithium salts, and above-mentioned positive active material precursor and above-mentioned addition source metal is made to be easy reaction.

Also, according to an embodiment, above-mentioned positive active material precursor and above-mentioned addition source metal, lithium salts to mixing into Before row is fired, the above-mentioned positive active material precursor and above-mentioned addition source metal, above-mentioned lithium salts of mixing can be mixed.On for example, It states positive active material precursor and above-mentioned addition source metal, above-mentioned lithium salts can be with physical mixed (for example, ball milling, hand mix) Process mixes precursor.

Hereinafter, illustrating the specific preparation method of the positive active material of embodiment present invention as described above.

Prepare embodiment 1-1~embodiment 1-4 positive active material

To after the distilled water of co-precipitation functional group (capacity 17L, the power of rotation motor are 750W or more) addition 4.5L, N is supplied to functional group with the speed of 2.5L/min₂Gas makes the temperature of functional group maintain 45 DEG C and stir with 350rpm.It will Nickel sulfate solution, cobalt sulfate solution and the manganese sulfate solution of 2M concentration are with the sodium hydroxide water of 0.187L/hr, 4M concentration Solution continuously puts into 15~35 hours with 0.043L/hr with the ammonia solution of 0.187L/hr, 10.5M concentration to functional group, to make For Ni_0.90Co_0.05Mn_0.05(OH)₂Metal composite hydroxide.

The prepared Ni of filtering_0.90Co_0.05Mn_0.05(OH)₂Metal composite hydroxide and after washing with water, at 110 DEG C Vacuum drier dries 12 hours.Utilize the TiO of the addition metal source preparation comprising adding metal Ti₂。

According to embodiment 1-1, with the time ball milling mixing Ni of 7 hours under conditions of 100rpm_0.90Co_0.05Mn_0.05 (OH)₂Metal composite hydroxide and TiO₂, come be prepared for doping 0.5 molar percentage Ti embodiment 1-1 positive-active Precursors.

1.0,2.0,3.0 mole hundred of doping is prepared for by condition identical with embodiment 1-1 as described above and method Divide the embodiment 1-2 of the Ti of ratio, the positive active material precursor of embodiment 1-3 and embodiment 1-4.

With the molar ratio of 1:1 with the time ball milling mixing embodiment 1-1 of 1 hour to embodiment under conditions of 200rpm The positive active material precursor and lithium hydroxide (LiOHH of 1-4₂O it after), is heated with the heating rate of 2 DEG C/min, at 450 DEG C Temperature under the conditions of maintain 5 hours to perform pre-burned, later, 10 hours are fired under the conditions of 750 DEG C of temperature, come It is prepared for the positive electrode active material powder of the embodiment 1-1 to embodiment 1-4 such as following table 1.

Table 1

It distinguishes	Chemical formula
		Embodiment 1-1	Li[(Ni0.90Co0.05Mn0.05-)0.995Ti0.005]O2
Embodiment 1-2	Li[(Ni0.90Co0.05Mn0.05-)0.99Ti0.01]O2
		Embodiment 1-3	Li[(Ni0.90Co0.05Mn0.05-)0.98Ti0.02]O2
Embodiment 1-4	Li[(Ni0.90Co0.05Mn0.05-)0.97Ti0.03]O2

Prepare the positive active material of comparative example 1

In the preparation method of positive active material of the embodiment 1-1 as described above to embodiment 1-4, omit as upper State the TiO of addition source metal₂Ball milling process be prepared for Li [Ni_0.90Co_0.05Mn_0.05-]O₂Positive active material.

Prepare the positive active material of comparative example 2

Method identical with the preparation method of positive active material of embodiment 1-2 as described above prepares positive electrode active material Matter, with Ni that 7 hours are mixed under conditions of 100rpm_0.90Co_0.05Mn_0.05(OH)₂Metal composite hydroxide, TiO₂ Addition source metal and lithium salts are simultaneously fired, to be prepared for the Li [(Ni of comparative example 2_0.90Co_0.05Mn_0.05-)_0.99Ti_0.01]O₂Just Pole active material.

Fig. 3 is that the energy disperse spectroscopy of the positive active material precursor of 1-2 of the embodiment of the present invention maps data, and Fig. 4 is ratio of the present invention Energy disperse spectroscopy compared with the positive active material precursor of example 2 maps data, before Fig. 5 is the positive active material of 1-2 of the embodiment of the present invention The electron scanning micrograph of body, Fig. 6 are that the scanning electron microscope of the positive active material precursor of comparative example 2 of the present invention is shone Piece, Fig. 7 are that the energy disperse spectroscopy of the positive active material precursor of comparative example 2 of the present invention maps data and electron scanning micrograph.

Referring to Fig. 3 to Fig. 7, confirm that the energy disperse spectroscopy of the positive active material precursor of embodiment 1-2 and comparative example 2 maps data And shoot electron scanning micrograph.(b) of Fig. 7 partially maps data for the energy disperse spectroscopy of part (a) of Fig. 7.

As shown in Fig. 3 to Fig. 7, in case of examples 1 to 2, positive active material precursor (preparation Ni_0.90Co_0.05Mn_0.05(OH)₂Metal composite hydroxide) surface can largely exist as addition source metal TiO₂.On the contrary, In the case where comparative example 2, compared to the positive active material precursor (Ni of preparation_0.90Co_0.05Mn_0.05(OH)₂Metal composite hydrogen Oxide) surface, the surface of LiOH can largely exist as addition source metal TiO₂.In particular, from part (a) of Fig. 7 And (b) partially it is found that there are the region of LiOH (region shown with dotted yellow line), there are a large amount of TiO₂。

Fig. 8 is the service life of the lithium secondary battery of positive active material of the detection comprising 1-2 of the embodiment of the present invention and comparative example 2 The chart of characteristic.

Referring to Fig. 8, prepared half-cell (half cell) using the positive active material of embodiment 1-2 and comparative example 2, and It has detected under conditions of cut off (cut off) 2.7~4.3V, 0.5C, 30 DEG C and is held according to the electric discharge of charge and discharge cycles number Amount.

As shown in figure 8, the case where compared to including the positive active material of comparative example 2, the anode comprising embodiment 1-2 is living Discharge capacity and life characteristic in the case where property substance is significantly outstanding.

Finally, it compared to disposable mixed cathode active material precursor, addition source metal and lithium salts and fires, such as present invention Embodiment, the method that mix and fire with lithium salts is equably adulterates after mixed cathode active material precursor and addition source metal The effective ways of metal are added, therefore, the capacity characteristic and life characteristic of lithium secondary battery are improved.

Fig. 9 is lithium two of the detection comprising 1-1 of the embodiment of the present invention to embodiment 1-4 and the positive active material of comparative example 1 The chart of the capacity characteristic of primary cell, Figure 10 be detection comprising 1-1 of the embodiment of the present invention to embodiment 1-4 and comparative example 1 just The chart of the life characteristic of the lithium secondary battery of pole active material.

Referring to Fig. 9 and Figure 10, half electricity of positive active material preparation of comparative example 1, embodiment 1-1 to embodiment 1-4 are utilized Discharge capacity is detected under conditions of 2.7~4.3V of cut off, 0.1C, 25 DEG C, in 2.7~4.3V of cut off, 0.5C, 25 in pond The discharge capacity according to charge and discharge cycles number is detected under conditions of DEG C.Testing result such as Fig. 9, Figure 10 and following table 2.

Table 2

From Fig. 9, Figure 10 and table 2 it is found that compared to lithium secondary battery prepared by the positive active material using comparative example 1, It is significant using the discharge capacity and life characteristic of the secondary cell of the positive active material preparation of embodiment 1-1 to embodiment 1-3 It is outstanding.

In particular, adding gold compared to the conduct for adulterating 0.5~2.0 molar percentage according to embodiment 1-1 to embodiment 1-3 The case where Ti of category, in the case where adulterating the Ti as addition metal of 3.0 molar percentages according to embodiment 1-4, the service life Characteristic significantly reduces.In other words, doping adds metal Ti and controls concentration small in the positive active material of high concentration of nickel Method in the range of 3.0 molar percentages is to improve the effective ways of life characteristic and capacity characteristic.

Figure 11 to Figure 15 is positive active material of the detection comprising comparative example 1 of the present invention and embodiment 1-1 to embodiment 1-4 Lithium secondary battery differential capacitance chart, Figure 16 is for illustrate basis comprising comparative example 1 of the present invention and embodiment 1-1 extremely The chart of the volume change of the charge and discharge number of the lithium secondary battery of the positive active material of embodiment 1-4.

Referring to Fig.1 1 to Figure 16, as described above, utilizing comparative example 1 and the positive electrode active material of embodiment 1-1 to embodiment 1-4 Matter prepares half-cell, the range of 2.7~4.3V, 30 DEG C of evaluation temperature, 0.5C charge condition under detection according to charge and discharge The differential capacitance of number.Also, as shown in figure 16, in the differential capacitance detection chart of Figure 11 to Figure 15 based on charge and discharge number 4.1~4.3V in, make integral area normalize (normalized).

From Figure 11 to Figure 15 it is found that with charge and discharge are carried out, embodiment 1-1 to embodiment 1-4 and the positive of comparative example 1 live Property substance successively has H1 phase, H1+M phase, M phase, M+H2 phase, H2 phase, H2+H3 phase, H3 phase, H2+H3 phase Position, M+H2 phase, M phase, H1+M phase, H1 phase.In Figure 11 into Figure 15, H1 phase is indicating Examples and Comparative Examples just Pole active material indicates embodiment and compares with the crystalline texture along c-axis direction with intrinsic lattice constant, H2 phase For the positive active material of example with having the crystalline texture for being longer than intrinsic lattice constant along c-axis direction, H3 phase indicates real The positive active material of example and comparative example is applied with the knot of the lattice constant along c-axis direction with shorter than intrinsic lattice constant Crystal structure, M phase indicate monoclinic system crystal structure.

Also, it in the case where adulterating the Ti as addition metal of 3 molar percentages, is such as described in detail referring to Fig. 9 and Figure 10 Content, compared to doping less than 3 molar percentages Ti the case where, the peak value within the scope of 4.1~4.3V is small, 4.1~4.3V Integral area in range is narrow, and therefore, capacity is small.

Also, undoped with as addition metal Ti in the case where, as shown in figure 11, with progress charge and discharge number, The peak value of H2 and H3 phase is sharply reduced.In other words, within the scope of 4.1~4.3V, integral area is sharply reduced, such as referring to Fig. 9 And the content that Figure 10 is described in detail, in the case of comparative example 1, capacity is sharply reduced according to charge and discharge number.

On the contrary, in the case where embodiment 1-1 to embodiment 1-3, it is secondary with charge and discharge are carried out as shown in Figure 12 to Figure 14 Number, can be by the substantially constant maintenance of the peak value of H2 and H3 phase.That is, according to charge and discharge number, the generation ratio of H2 and H3 phase The variable quantity of rate as the Ti of addition metal by substantially reducing.In other words, in the range of 4.1~4.3V, integral area is real The constant maintenance in matter ground, the content being such as described in detail referring to Fig. 9 and Figure 10 can make capacity according to filling in situation according to the embodiment The phenomenon that discharge time is reduced minimizes.Specifically, as shown in figure 16, the 1-1 of the embodiment of the present invention to embodiment 1-4 the case where Under, under the conditions of 100 charge and discharge, integral area within the scope of 4.1~4.3V reduction amount be 10% or less.

Prepare the positive active material of embodiment 2-1 to embodiment 2-3

Ni is prepared according to embodiment 1-1_0.90Co_0.05Mn_0.05(OH)₂Metal composite hydroxide, under conditions of 100rpm With the time ball milling mixing Ni of 7 hours_0.90Co_0.05Mn_0.05(OH)₂Metal composite hydroxide and Al (OH)₃, to be prepared for mixing The positive active material precursor of the embodiment 2-1 of the Al of miscellaneous 0.5 molar percentage.

Doping 1.0 molar percentages, 2.0 are prepared for by condition identical with embodiment 2-1 as described above and method The positive active material precursor of the embodiment 2-2 and embodiment 2-3 of the Al of molar percentage.

Under conditions of 200rpm just with the embodiment 2-1 to 2-3 of the time ball milling mixing 1:1 molar ratio of 1 hour After pole active substance precursors and lithium hydroxide, heated with the heating rate of 2 DEG C/min, and maintain 5 under the conditions of 450 DEG C of temperature A hour performs pre-burned, then, fires 10 hours, under the conditions of 750 DEG C of temperature to be prepared for such as following Table 3 The positive electrode active material powder of embodiment 2-1 to embodiment 2-3.

Table 3

It distinguishes	Chemical formula
		Embodiment 2-1	Li[(Ni0.90Co0.05Mn0.05-)0.995Al0.005]O2
Embodiment 2-2	Li[(Ni0.90Co0.05Mn0.05-)0.99Al0.01]O2
		Embodiment 2-3	Li[(Ni0.90Co0.05Mn0.05-)0.98Al0.02]O2

Figure 17 is lithium two of the detection comprising 2-1 of the embodiment of the present invention to embodiment 2-3 and the positive active material of comparative example 1 The chart of the capacity characteristic of primary cell, Figure 18 be detection comprising 2-1 of the embodiment of the present invention to embodiment 2-3 and comparative example 1 just The chart of the life characteristic of the lithium secondary battery of pole active material.

7 and Figure 18 referring to Fig.1 utilizes half electricity of positive active material preparation of comparative example 1, embodiment 1-1 to embodiment 1-4 Discharge capacity is detected under conditions of 2.7~4.3V of cut off, 0.1C, 25 DEG C, in 2.7~4.3V of cut off, 0.5C, 25 in pond The discharge capacity according to charge and discharge cycles number is detected under conditions of DEG C.Testing result such as Figure 17, Figure 18 and following table 4.

Table 4

From Figure 17, Figure 18 and table 4 it is found that compared to lithium secondary battery prepared by the positive active material using comparative example 1, It is significantly outstanding using the discharge capacity and life characteristic of the secondary cell of the positive active material preparation of embodiment 2-1 to 2-3.

In particular, adding gold compared to the conduct for adulterating 0.5~1.0 molar percentage according to embodiment 2-1 to embodiment 2-2 The case where Al of category, adulterates the service life spy in the case where the Al as addition metal of 2.0 molar percentages according to embodiment 2-3 Property significantly reduce.In other words, metal Al is added in the positive active material doping of high concentration of nickel and control concentration less than 2.0 Method in the range of molar percentage is to improve the effective ways of life characteristic and capacity characteristic.

Figure 19 to Figure 21 is that the lithium of positive active material of the detection comprising 2-1 of the embodiment of the present invention to embodiment 2-3 is secondary The chart of the differential capacitance of battery.

1, Figure 19 to Figure 21 referring to Fig.1, as described above, utilizing comparative example 1 and the anode of embodiment 2-1 to embodiment 2-3 Active material prepares half-cell, the range of 2.7~4.3V, 30 DEG C of evaluation temperature, 0.5C charge condition under detect charge and discharge The differential capacitance of electric number.

From Figure 11, Figure 19 to Figure 21 it is found that with charge and discharge are carried out, embodiment 2-1 to 2-3 and the positive of comparative example 1 live Property substance successively has H1 phase, H1+M phase, M phase, M+H2 phase, H2 phase, H2+H3 phase, H3 phase, H2+H3 phase Position, M+H2 phase, M phase, H1+M phase, H1 phase.

Also, such as the content that 7 and Figure 18 referring to Fig.1 is described in detail, compared to doping less than 2 molar percentages Al the case where, In the case where adulterating the Al as addition metal of 2 molar percentages, the peak value within the scope of 4.1~4.3V is small, 4.1~ Integral area in the range of 4.3V is narrow, and therefore, capacity is small.

Also, the content as described in referring to Fig.1 1, undoped with as the Ti for adding metal, with being filled The peak value of discharge time, H2 and H3 phase is sharply reduced.

On the contrary, as shown in Figure 19 to Figure 20, according to embodiment 2-1 to embodiment 2-2, with progress charge and discharge Electric number, the substantive constant maintenance of the peak value of H2 and H3 phase.That is, according to charge and discharge number, the generation ratio of H2 and H3 phase Variable quantity by as addition metal Al substantially reduce.In other words, in the range of 4.1~4.3V, integral area essence Property constant maintenance, the content that such as 7 and Figure 18 is described in detail referring to Fig.1 can make capacity according to charge and discharge in situation according to the embodiment The case where number substantially reduces minimum.

Figure 22 to Figure 24 is sweeping for the section of the positive active material of shooting 2-2 according to embodiments of the present invention and comparative example 1 Retouch electron micrograph.

Referring to Figure 22 to Figure 24, (a) of Figure 22 partially and (b) is partially respectively utilizing embodiment 2-2 and comparative example 1 just Pole active material prepares button cell and shoots the scanning of the positive active material of embodiment 2-2 and comparative example 1 after the 4.3V that charges Electron micrograph, part (a) of Figure 23 and (b) part are respectively the positive electrode active material using embodiment 2-2 and comparative example 1 Matter prepares button cell and the 4.3V that charges, electrolyte under the conditions of 60 DEG C of temperature save 5 after shooting embodiment 2-2 and The electron scanning micrograph of the positive active material of comparative example 1, part (a) of Figure 24 and (b) part are respectively using real The positive active material for applying a 2-2 and comparative example 1 prepares button cell and the 4.3V that charges, electrolysis under the conditions of 60 DEG C of temperature The electron scanning micrograph of the positive active material of shooting embodiment 2-2 and comparative example 1 after liquid saves 10.

From Figure 22 to Figure 24 it is found that the particle structure of the positive active material of comparative example 1 is easy decay, on the contrary, embodiment The positive active material of 2-2 does not also decay under the high temperature conditions.

Finally, it is known that, embodiment according to the present invention adulterates the method for addition metal to positive active material to improve just The structure of pole active material particle, machinery, chemical stability effective ways.

Figure 25 is the chart for detecting the sheet resistance of positive active material of 2-2 of the embodiment of the present invention, and Figure 26 is to detect this The chart of the sheet resistance of the positive active material of invention comparative example 1, Figure 27 are to compare 2-2 of the embodiment of the present invention and comparative example 1 Positive active material Rct value chart.

Referring to Figure 25 to Figure 27, embodiment 2-2 and comparative example 1 are detected by electrochemical impedance spectroscopy (EIS) analysis method The sheet resistance of positive active material.In 1~50 charge and discharge number process, the positive electrode active material of comparative example 1 is detected The sheet resistance of matter is imperceptibly less than the sheet resistance of the positive active material of embodiment 2-2.But in 50 times or more charge and discharges In electric number process, compared to the sheet resistance of the positive active material of comparative example 1, the positive active material of embodiment 2-2 Sheet resistance reduces, and its significant difference increases.

Finally, embodiment according to the present invention adulterates the method for addition metal to positive active material to reduce according to charge and discharge The sheet resistance of the positive active material particle of electric number improves the effective ways of life characteristic and capacity characteristic.

Figure 28 is the thermal stability for detecting the positive active material of 2-1 of the embodiment of the present invention, embodiment 2-2 and comparative example 1 Chart.

Referring to Figure 28, by differential scanning calorimetry (DSC), (sweep speed (scan rate) is 5 DEG C/min, cut off For the condition of 4.3V) detection embodiment 2-1, embodiment 2-2 and comparative example 1 positive active material thermal stability.

Table 5

As shown in Figure 28 and table 5, compared to the positive active material of comparative example 1, embodiment 2-1's and embodiment 2-2 The significant ground of temperature that peak value occurs in positive active material is high.

Finally, embodiment according to the present invention adulterates the method for addition metal to positive active material to improve positive-active The effective ways of the thermal stability of material particle.

Prepare the positive active material of embodiment 3-1 to embodiment 3-3

To co-precipitation functional group (capacity 17L, rotation motor power be 750W or more) addition 4.5L distilled water after, N is supplied to functional group with the speed of 2.5L/min₂Gas makes the temperature of functional group maintain 45 DEG C and stir with 350rpm.It will The nickel sulfate solution of 2M concentration is with the sodium hydrate aqueous solution of 0.187L/hr, 4M concentration with 0.187L/hr, 10.5M concentration Ammonia solution continuously puts into 15~35 hours with 0.043L/hr to functional group, to be prepared for Ni (OH)₂Metal composite hydroxide Object.

The prepared Ni (OH) of filtering₂Metal composite hydroxide and after washing with water, it is dry in 110 DEG C of vacuum driers Dry 12 hours.Utilize the ZrO of the addition metal source preparation comprising adding metal Zr₂。

According to embodiment 3-1, at 100 rpm with the time ball milling mixing Ni (OH) of 7 hours₂Metal composite hydrogen Oxide and ZrO₂, come prepare the Zr for being doped with 0.5 molar percentage embodiment 3-1 positive active material precursor.

Doping 1.0 molar percentages, 2.0 are prepared for by condition identical with embodiment 3-1 as described above and method The positive active material precursor of the embodiment 3-2 and embodiment 3-3 of the Zr of molar percentage.

With the molar ratio of 1:1 under conditions of 200rpm with the time ball milling mixing embodiment 3-1 of 1 hour to 3-3's After positive active material precursor and lithium hydroxide, is heated with the heating rate of 2 DEG C/min, maintain 5 under the conditions of 450 DEG C of temperature A hour performs pre-burned, later, fires 10 hours, under the conditions of 650~670 DEG C of temperature to be prepared for embodiment The positive electrode active material powder of 3-1 to embodiment 3-3.

Prepare the positive active material of embodiment 3-4

Ni is prepared according to embodiment 1-1_0.90Co_0.05Mn_0.05(OH)₂Metal composite hydroxide, under conditions of 100rpm With the time ball milling mixing Ni of 7 hours_0.90Co_0.05Mn_0.05(OH)₂Metal composite hydroxide and ZrO₂, to be prepared for adulterating The positive active material precursor of the embodiment 3-4 of the Zr of 0.5 molar percentage.

Later, in the identical method of the method for the detailed description with embodiment 3-1 into embodiment 3-3 and condition by embodiment 3- 4 positive active material precursor mixes and is fired to be prepared for the positive electrode active material powder of embodiment 3-4 with lithium salts.

Table 6

It distinguishes	Chemical formula
		Embodiment 3-1	LiNi0.995Zr0.005O2
Embodiment 3-2	LiNi0.99Zr0.01O2
		Embodiment 3-3	LiNi0.98Zr0.02O2
Embodiment 3-4	Li[(Ni0.90Co0.05Mn0.05-)0.995Zr0.005]O2

Prepare the positive active material of comparative example 3

Omission and conduct in the preparation method of positive active material of the embodiment 3-1 as described above to embodiment 3-3 The ZrO of above-mentioned addition source metal₂Ball milling process be prepared for LiNiO₂Positive active material.

Figure 29 is lithium two of the detection comprising 3-1 of the embodiment of the present invention to embodiment 3-3 and the positive active material of comparative example 3 The chart of the capacity characteristic of primary cell, Figure 30 be detection comprising 3-1 of the embodiment of the present invention to embodiment 3-3 and comparative example 3 just The chart of the life characteristic of the lithium secondary battery of pole active material.

Referring to Figure 29 and Figure 30, half electricity of positive active material preparation of comparative example 3, embodiment 3-1 to embodiment 3-3 are utilized Discharge capacity is detected under conditions of 2.7~4.3V of cut off, 0.1C, 25 DEG C, in 2.7~4.3V of cut off, 0.5C, 25 in pond The discharge capacity according to charge and discharge cycles number is detected under conditions of DEG C.Testing result such as Figure 29, Figure 30 and following table 7.

Table 7

From Figure 29, Figure 30 and table 7 it is found that compared to lithium secondary battery prepared by the positive active material using comparative example 3, It is significantly outstanding using the discharge capacity and life characteristic of the secondary cell of the positive active material preparation of embodiment 3-1 to 3-2.

In particular, adding gold compared to the conduct for adulterating 0.5~1.0 molar percentage according to embodiment 3-1 to embodiment 3-2 The case where Zr of category, in the case where adulterating the Zr as addition metal of 2.0 molar percentages according to embodiment 3-3, the service life Characteristic significantly reduces.In other words, it is being less than in the positive active material doping addition metal Zr of high concentration of nickel and by concentration control Method in the range of 2.0 molar percentages is to improve the effective ways of life characteristic and capacity characteristic.

Also, such as embodiment 3-1 and embodiment 3-4, even if the case where the addition metal of doping same concentrations, in containing for nickel In the case that amount is high, it is bigger that problem is reduced according to the capacity of charge and discharge number.In other words, increasing nickel to improve capacity In the case where content, it can occur to reduce problem according to the capacity of charge and discharge number, in the case, such as the embodiment of the present invention, The method of doping addition metal is to efficiently solve method.

Figure 31 to Figure 35 is positive active material of the detection comprising comparative example 3 of the present invention, embodiment 3-1 to embodiment 3-4 Lithium secondary battery differential capacitance chart.

Referring to Figure 31 to Figure 35, as described above, utilizing comparative example 3 and the positive electrode active material of embodiment 3-1 to embodiment 3-4 Matter prepares half-cell, the range of 2.7~4.3V, 30 DEG C of evaluation temperature, 0.5C charge condition under detection according to charge and discharge The differential capacitance of number.

From Figure 31 to Figure 35 it is found that with charge and discharge, the positive active material of embodiment 3-1 to 3-4 and comparative example 3 is carried out Successively there is H1 phase, H1+M phase, M phase, M+H2 phase, H2 phase, H2+H3 phase, H3 phase, H2+H3 phase, M+H2 Phase, M phase, H1+M phase, H1 phase.

Also, undoped with as addition metal Zr in the case where, with progress charge and discharge number, H2 and H3 phase Peak value is sharply reduced.

On the contrary, in the case where embodiment 3-1 duty embodiment 3-2 and embodiment 3-4, as shown in Figure 29 to Figure 30, with Charge and discharge number is carried out, compared to comparative example 3, the variable quantity of the peak value of H2 and H3 phase is reduced.That is, with charge and discharge time are carried out Number, the variable quantity of the generation ratio of H2 and H3 phase passes through to be reduced as the Zr of addition metal.

Figure 36 to Figure 39 is the table of detection comparative example 3 of the present invention, positive active material of the embodiment 3-1 to embodiment 3-3 The chart of surface resistance.

Referring to Figure 36 to Figure 39, embodiment 3-1 is detected by electrochemical impedance spectral analysis method and to embodiment 3-3 and is compared The sheet resistance of the positive active material of example 3.

Table 8

From Figure 36 to Figure 39 and table 8 it is found that the positive active material compared to comparative example 3 sheet resistance, embodiment 3-1 Sheet resistance to the positive active material of embodiment 3-3 is significantly small.Also, as charge and discharge number increases, significant difference Increase.Finally, embodiment according to the present invention adulterates the method for addition metal to positive active material to reduce according to charge and discharge The sheet resistance of the positive active material particle of number improves the effective ways of life characteristic and capacity characteristic.

Figure 40 be detection comparative example 3 of the present invention, embodiment 3-1 and embodiment 3-3 positive active material thermal stability Chart.

Referring to Figure 40, pass through differential scanning calorimetry (sweep speed is 5 DEG C/min, and cut off is the condition of 4.3V) detection Comparative example 3, embodiment 3-1 and embodiment 3-3 positive active material thermal stability.

Table 9

As shown in Figure 40 and table 9, compared to the positive active material of comparative example 3, embodiment 3-1's and embodiment 3-3 The significant ground of temperature that peak value occurs in positive active material is high.

Finally, embodiment according to the present invention adulterates the method for addition metal to positive active material to improve positive-active The effective ways of the thermal stability of material particle.

Figure 41 is that detection includes comparative example 1 of the present invention, embodiment 1-1, embodiment 1-2, embodiment 2-2 and embodiment 3-4 Positive active material lithium secondary battery capacity characteristic chart, Figure 42 be detection include comparative example 1 of the present invention, embodiment The chart of the life characteristic of the lithium secondary battery of the positive active material of 1-1, embodiment 1-2, embodiment 2-2 and embodiment 3-4.

Referring to Figure 41 and Figure 42, comparative example 1, embodiment 1-1, embodiment 1-2, embodiment 2-2 and embodiment 3-4 are utilized Positive active material prepares half-cell, detects discharge capacity under conditions of 2.7~4.3V of cut off, 0.1C, 25 DEG C, is ending 2.7~4.3V of point, 0.5C, under conditions of 25 DEG C detection according to the discharge capacity of charge and discharge cycles number.

From Figure 41 and Figure 42 it is found that being utilized compared to lithium secondary battery prepared by the positive active material using comparative example 1 The electric discharge of the secondary cell of the positive active material preparation of embodiment 1-1, embodiment 1-2, embodiment 2-2 and embodiment 3-4 is held Amount and life characteristic are significantly outstanding.

In particular, the case where addition metal compared to embodiment 2-2 and embodiment 3-4 is Al and Zr, embodiment 1-1 and reality The addition metal for applying a 1-2 is significantly outstanding for the life characteristic improvement effect in the case where Ti.

Figure 43 and Figure 44 is for illustrating according to comprising comparative example 1 of the present invention, embodiment 1-1, embodiment 1-2, embodiment The chart of the volume change of the charge and discharge number of the lithium secondary battery of the positive active material of 2-2 and embodiment 3-4.

Referring to Figure 43 and Figure 44, comparative example 1, embodiment 1-1, embodiment 1-2, embodiment 2-2 and embodiment 3-4 are utilized Positive active material prepares half-cell, in the embodiment 1-1 of Figure 11, Figure 12, Figure 13, Figure 20 and Figure 35, embodiment 1-2, implements In 4.1~4.3V based on charge and discharge number in the differential capacitance detection chart of example 2-2 and embodiment 3-4, make integral area Normalization.Also, the embodiment 1-1 in Figure 11, Figure 12, Figure 13, Figure 20 and Figure 35, embodiment 1-2, embodiment 2-2 and implementation In the differential capacitance detection chart of example 3-4, highest is detected in a manner of such as following table 10 to table 14 in the range of 4.1~4.3V Peak value simultaneously normalizes.

Table 10

Table 11

Table 12

Table 13

Table 14

It as can be seen from Figure 43, is including doping addition according to embodiment 1-1, embodiment 1-2, embodiment 2-2 and embodiment 3-4 Integral area in the case where the secondary cell of the positive active material of metal, in 4.1~4.3V based on charge and discharge number The reduction amount of (capacity) is 10% hereinafter, on the contrary, including the positive active material undoped with addition metal according to comparative example 1 In the case where secondary cell, according to charge and discharge number, the integral area (capacity) in 4.1~4.3V is substantially reduced.

It also, is including as can be seen from Figure 43, to mix according to embodiment 1-1, embodiment 1-2, embodiment 2-2 and embodiment 3-4 It is aobvious according to the reduction amount of the peak-peak of charge and discharge number in the case where the secondary cell of the positive active material of miscellaneous addition metal Write it is low, on the contrary, according to comparative example 1 include undoped with addition metal positive active material secondary cell in the case where, most Peak value is substantially reduced according to charge and discharge number.

Figure 45 is the positive active material of detection comparative example 1 of the present invention, embodiment 1-1 to embodiment 1-4 and embodiment 2-2 Particle intensity chart.

Referring to Figure 45, comparative example 1, embodiment 1-1 to embodiment 1-4 and embodiment 2-2 positive active material particle For example following tables 15 of detected intensities.

Table 15

From table 15 and Figure 45 it is found that compared to the positive active material according to comparative example 1 undoped with addition metal, in basis In the case where the positive active material of embodiment 1-1 to embodiment 1-4 and embodiment 2-2 doping addition metal, particle intensity is aobvious It writes outstanding.

Finally, the content as described in referring to Figure 22 to Figure 24, according to an embodiment of the invention, being adulterated to positive active material The method of addition metal is to improve the effective ways of the structure of positive active material particle, machinery, chemical stability.

Figure 46 to Figure 49 is the chart for illustrating the differential capacitance of the variable quantity of the H2 and H3 phase according to the content of nickel, Figure 50 is the volume change for illustrating the charge and discharge number of the lithium secondary battery according to the positive active material using Figure 47 Chart.

Referring to Figure 46 to Figure 50, the positive active material of comparative example 1 is prepared, the concentration of nickel, cobalt and manganese is controlled 95: 2.5:2.5,90:5:5,80:1:1,6:2:2 prepare positive active material, and in the range of 2.7~4.3V, 30 DEG C of evaluation Temperature, 0.5C charge condition under detection according to the differential capacitance of charge and discharge number.Also, as shown in figure 50, in the micro- of Figure 47 Divide in 4.1~4.3V based on charge and discharge number in capacitance detecting chart, normalizes integral area.

From Figure 46 to Figure 49 it is found that in the case where the concentration of nickel is greater than 60 molar percentage, in the range of 4.1~4.3V Interior generation H2 and H3 phase.Also, with the increase of nickel concentration, in initial charge/discharge circulation, the peak value of H2 and H3 phase is high. In other words, with the increase of nickel concentration, capacity greatly increases in the range of 4.1~4.3V.

On the contrary, nickel concentration is higher, the peak value of the H2 and H3 phase within the scope of 4.1~4.3V with charge and discharge number is carried out Sharply reduce.In other words, with the increase of nickel concentration, the capacity within the scope of 4.1~4.3V is sharply reduced.

Therefore, in the case where positive active material of the embodiment according to the present invention preparation comprising addition metal, as above It is described, the case where peak value of H2 and H3 phase can be made to reduce in the range of 4.1~4.3V minimum finally can make to have The case where melting is reduced according to charge and discharge number in the positive active material of high concentration of nickel minimizes.

Figure 51 is the service life according to the lithium secondary battery of positive active material of the nickel concentration detection comprising the embodiment of the present invention The chart of characteristic.

Referring to Figure 51, such as following tables 16, by the method preparation of embodiment as described above according to experimental example 1-1 to experiment The positive active material and lithium secondary battery comprising it of example 4-2, control nickel, cobalt, manganese and the concentration for adding metal Ti, according to filling The service life of discharge time maintains the testing result such as table 17 of characteristic.

Table 16

Table 17

As shown in Figure 51 and table 17, with the increase of nickel concentration, ratio is increased according to the capacity of addition metal, in other words, Life characteristic maintains efficiency to significantly improve.That is, high in nickel concentration, nickel concentration is the high concentration anode of 60 molar percentages or more In active material, the service life for expressing the addition metal of technical idea according to an embodiment of the present invention maintains effect, and nickel concentration more increases Add, the service life maintains significant effect to improve.

Figure 52 is the block diagram for showing the electric car of one embodiment of the invention.

The electric car 1000 of one embodiment of the invention may include motor 1010, speed changer 1020, axle 1030, battery pack 1040, at least one of energy hole portion 1050 and charging part 1060.

The electric energy of above-mentioned battery pack 1040 can be converted to kinetic energy by said motor 1010.Said motor 1010 can be by above-mentioned Speed changer 1020 provides the kinetic energy of conversion to above-mentioned axle 1030.Said motor 1010 can be by single motor or multiple motor shapes At.For example, said motor 1010 may include supplying to front wheel axle in the case where said motor 1010 is formed by multiple motors The preceding wheel motor of kinetic energy and the rear wheel motor that kinetic energy is supplied to axletree of rear wheel.

Above-mentioned speed changer 1020, can be to meet driver institute between said motor 1010 and above-mentioned axle 1030 The mode for the driving environment wanted carries out speed change to provide to above-mentioned axle 1030 to from the kinetic energy of said motor 1010.

Above-mentioned battery pack 1040 can store the electric energy from above-mentioned charging part 1060, and can provide storage to said motor 1010 Electric energy.Above-mentioned battery pack 1040 can directly feed electric energy to said motor 1010, can also pass through above-mentioned energy hole portion 1050 Supply of electrical energy.

In the case, above-mentioned battery pack 1040 may include at least one element cell to be formed.Also, element cell can Including lithium secondary battery, above-mentioned lithium secondary battery includes the positive active material of embodiment present invention as described above, but not It is defined in this, it may include the secondary cell of the various modes such as lithium class secondary cell.On the other hand, element cell can refer to each for generation The term of a battery, battery pack can be that each element cell is connected in a manner of with desired voltage and/or capacity Element cell aggregate.

Above-mentioned energy hole portion 1050 can control above-mentioned battery pack 1040.In other words, above-mentioned energy hole portion 1050 can It is carried out in a manner of making that there is required voltage, electric current, waveform etc. from above-mentioned battery pack 1040 to the energy of said motor 1010 Control.For this purpose, above-mentioned energy hole portion 1050 may include at least one of passive electric device and active electric power device.

Above-mentioned charging part 1060 can receive electric power from external power supply 1070 shown in Figure 46 to mention to above-mentioned battery pack 1040 For.Above-mentioned charging part 1060 can integrally control charged state.For example, unlatching/closing of the controllable charging of above-mentioned charging part 1060 (on/off) and charging rate etc..

Figure 53 is the perspective view of the electric car of one embodiment of the invention.

Referring to Figure 53, above-mentioned battery pack 1040 can combine below electric car 1000.For example, above-mentioned battery pack 1040 can be in the width with the wide cut direction along above-mentioned electric car 1000 and along the length direction of above-mentioned automobile 1000 The shape of extension.More specifically, above-mentioned battery pack 1040 can extend to rear suspension from front suspension.Therefore, above-mentioned battery pack 1040 can provide the space that can encapsulate more element cells.Also, above-mentioned battery pack 1040 is arranged in conjunction with car body lower end, because This, reduces the weight center of car body, to improve the driving safety of electric car 1000.

Figure 54 is the battery pack volume figure for illustrating one embodiment of the invention.

Referring to Figure 54, above-mentioned battery pack 1040 can be reserved for multiple element cells 1043.

Above-mentioned battery pack 1040 may include lower case 1041 and upper body 1042.Above-mentioned lower case 1041 may include Flange 1044, the hole by being set to above-mentioned upper body 1045 connect bolt 1045 with above-mentioned flange 1044, above-mentioned to make Lower case 1041 is combined with above-mentioned upper body 1042.

In the case, in order to improve the stability of above-mentioned battery pack 1040, above-mentioned lower case and upper body can be by The substance manufacture for minimizing moisture and Oxygen permeation.For example, above-mentioned lower case and upper body can by aluminium, aluminium alloy, plastics, At least one of carbon compound substance is formed.Also, it can between above-mentioned lower case 1041 and above-mentioned upper body 1042 It is provided with the sealant 1049 of impermeability.

Also, above-mentioned battery pack 1040 may include for controlling said units battery 1043 or improving the structure of stability. For example, above-mentioned battery pack 1040 may include the control terminal for controlling the element cell 1043 inside above-mentioned battery pack 1040 1047.Also, for example, the thermal runaway (thermal runaway) of said units battery 1043 or the above-mentioned list of control in order to prevent The temperature of first battery 1043, above-mentioned battery pack 1040 may include cooling line 1046.Also, for example, above-mentioned battery pack 1040 can wrap Include the gas vent 1048 for spraying the gas inside above-mentioned battery pack 1040.

More than, the present invention is described in detail by preferred embodiment, the scope of the present invention is not limited to specific embodiment, It need to be explained by inventing claimed range.As long as also, those skilled in the art can be without departing from this hair It modifies and deforms in bright range.

Industrial availability

The positive active material of the embodiment of the present invention and it can be used in electric vehicle, portable shifting comprising its lithium secondary battery The various industrial fields of dynamic equipment, energy storage device etc..