阅读说明：本技术 极片、电芯以及电池 (Pole piece, battery core and battery ) 是由 李帅 余仕禧 张正德 于 2019-02-19 设计创作，主要内容包括：本发明公开了一种极片、电芯以及电池,极片包括：绝缘基体、第一导电层、第二导电层、第一活性物质层和第二活性物质层。绝缘基体包括相对的第一表面和第二表面；第一导电层设置于第一表面；第二导电层设置于第二表面；第一活性物质层设置于第一导电层；第二活性物质层设置于第二导电层。由此,通过绝缘基体、第一导电层、第二导电层、第一活性物质层和第二活性物质层配合,能够将正极极片和负极极片集成在一条极片上,可以降低对电池的卷绕设备的要求,也可以减少极片卷绕时错位,从而可以提升电池的生产合格率,并且,通过在绝缘基体上设置第一导电层、第二导电层,能够降低极片金属含量,可以提高电池质量能量密度。(The invention discloses a pole piece, a battery cell and a battery, wherein the pole piece comprises: the semiconductor device includes an insulating substrate, a first conductive layer, a second conductive layer, a first active material layer, and a second active material layer. The insulating substrate comprises a first surface and a second surface which are opposite; the first conducting layer is arranged on the first surface; the second conducting layer is arranged on the second surface; the first active material layer is arranged on the first conductive layer; the second active material layer is disposed on the second conductive layer. From this, through insulating base member, first conducting layer, second conducting layer, first active material layer and the cooperation of second active material layer, can be with positive pole piece and negative pole piece integration on a polar plate, can reduce the requirement to the coiling equipment of battery, dislocation when also can reducing the pole piece and convolute to can promote the production qualification rate of battery, and, through setting up first conducting layer, second conducting layer on insulating base member, can reduce pole piece metal content, can improve battery quality energy density.)

1. A pole piece, comprising:

an insulating substrate comprising opposing first and second surfaces;

the first conducting layer is arranged on the first surface;

the second conducting layer is arranged on the second surface;

a first active material layer provided on the first conductive layer;

and a second active material layer provided on the second conductive layer, the first active material layer and the second active material layer having opposite polarities.

2. The pole piece of claim 1, wherein the thickness of the insulating base is 6-8um, the thickness of the first conducting layer and the second conducting layer are both 2-3um, and the total thickness of the insulating base, the first conducting layer and the second conducting layer is 10-14 um.

3. The pole piece of claim 1, wherein the insulating substrate comprises a first end face and a second end face opposite to each other in a length direction of the insulating substrate, and the first conductive layer has a minimum distance L1 from the first end face;

the second conductive layer has a minimum distance L2 from the first end face, wherein L2 is greater than L1.

4. The pole piece of claim 3, wherein the first active material layer has a minimum distance L1' from the first end face in the length direction of the insulating substrate;

the second active material layer has a minimum distance of L2 ' from the first end face, wherein L2 ' is greater than L1 '.

5. The pole piece of claim 4 wherein L1' is greater than L1 and the first conductive layer comprises a first uncoated region for providing a first tab.

6. The pole piece of claim 5 wherein the first tab is at a distance L3 from the first end face, L3 being less than L2.

7. The pole piece of claim 3, wherein the first conductive layer is at a minimum distance L4 from the second end face in a length direction of the insulating substrate;

the second conductive layer has a minimum distance L5 from the second end face, wherein L4 is greater than L5.

8. The pole piece of claim 7, wherein the first active material layer is at a minimum distance L4' from the second end face in the length direction of the insulating substrate;

the second active material layer has a minimum distance L5 ' from the second end face, wherein L4 ' is greater than L5 '.

9. The pole piece of claim 8 wherein L5' is greater than L5 and the second conductive layer includes a second uncoated region for providing a second tab.

10. The pole piece of claim 9 wherein the second tab is at a distance L6 from the second end face, L6 being less than L4.

11. The pole piece of claim 1, wherein the insulating matrix comprises one or more of polyimide, polyethylene, polyvinylidene fluoride, polytetrafluoroethylene.

12. The pole piece of claim 1, wherein the first conductive layer comprises one or more of aluminum, titanium, stainless steel, aluminum alloy, and titanium alloy;

the second conductive layer includes one or more of copper, titanium, nickel, a copper alloy, a nickel alloy, and a titanium alloy.

13. The pole piece of claim 1, wherein the first active material layer comprises one or more of lithium cobaltate, lithium manganate, lithium titanate, lithium iron phosphate, and lithium nickel cobalt manganate;

the second active material layer comprises one or more of graphite, silicon, lithium titanate.

14. A cell, comprising:

an isolation film; and

a pole piece according to any one of claims 1 to 13, wound with the separator film.

15. A battery, comprising:

an electrolyte;

packaging the shell; and

a cell according to claim 14.

Technical Field

The invention relates to the field of batteries, in particular to a pole piece, a battery core and a battery.

Background

At present, the lithium ion battery structure mainly has coiling formula and lamination formula, and considering that the production technology of lamination formula battery is complicated, the optimal rate is low, and is with high costs, and most batteries all adopt coiling formula structure, and common coiling formula structure battery needs positive pole piece, negative pole piece and two barrier films stacks to be four-layer structure and convolutes simultaneously, and the pole piece dislocation of coiling is difficult to control. Common lithium ion batteries all use copper foils and aluminum foils as current collectors, and through a coating process, negative electrode materials are coated on two sides of the copper foils to prepare negative electrode plates, positive electrode materials are coated on two sides of the aluminum foils to prepare positive electrode plates, when the electrode plates are cut, burrs are large, the situation that the cutters are sharp enough is guaranteed, and the burrs are prevented from exceeding the standard. The common welding positions of the tabs of the lithium ion batteries are all in the pole piece blank positions, so that when the positive pole piece and the negative pole piece are prepared, partial empty foil areas need to be reserved for welding the tabs, so that more metal aluminum is exposed, and the metal aluminum is in contact with a fully charged negative pole, so that the short circuit thermal runaway of the batteries is easily caused.

The disadvantages of the common lithium ion battery are: the energy density of the battery is low, and the isolating film and the current collector occupy more space of the lithium ion battery; the safety performance of the battery is poor, the cutting burrs of the metal current collector are large, the hollow aluminum foil is exposed to a large extent, and the risk of thermal runaway after the battery is short-circuited is large; the production cost of the battery is high, and the cutting knife is frequently changed in slitting and cutting; the winding equipment is complex; low production quality rate and uneven quality.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, an object of the present invention is to provide a pole piece, which can reduce the dislocation of the pole piece during winding, thereby improving the production yield of the battery and improving the quality and energy density of the battery.

The invention further provides a battery cell.

The invention further provides a battery.

The pole piece according to the invention comprises: the semiconductor device includes an insulating substrate, a first conductive layer, a second conductive layer, a first active material layer, and a second active material layer. The insulating substrate comprises a first surface and a second surface which are opposite; the first conducting layer is arranged on the first surface; the second conducting layer is arranged on the second surface; the first active material layer is arranged on the first conductive layer; the second active material layer is provided on the second conductive layer, and the first active material layer and the second active material layer have opposite polarities.

According to the pole piece, the insulating base body, the first conducting layer, the second conducting layer, the first active substance layer and the second active substance layer are matched, the positive pole piece and the negative pole piece can be integrated on one pole piece, the requirement on winding equipment of a battery can be lowered, dislocation during pole piece winding can be reduced, the production yield of the battery can be improved, the first conducting layer and the second conducting layer are arranged on the insulating base body, the metal content of the pole piece can be reduced, and the quality and energy density of the battery can be improved.

In some examples of the present invention, the thickness of the insulating base is 6-8um, the thickness of the first conductive layer and the thickness of the second conductive layer are both 2-3um, and the total thickness of the insulating base, the first conductive layer and the second conductive layer is 10-14 um.

In some examples of the present invention, the insulating substrate includes first and second opposing end faces in a length direction of the insulating substrate, and the first conductive layer has a minimum distance L1 from the first end face; the second conductive layer has a minimum distance L2 from the first end face, wherein L2 is greater than L1.

In some examples of the present invention, a minimum distance of the first active material layer from the first end face in a length direction of the insulating substrate is L1'; the second active material layer has a minimum distance of L2 ' from the first end face, wherein L2 ' is greater than L1 '.

In some examples of the invention, L1' is greater than L1 and the first conductive layer includes a first uncoated region for providing a first tab.

In some examples of the invention, the first tab is at a distance L3 from the first end face, and L3 is less than L2.

In some examples of the present invention, a minimum distance between the first conductive layer and the second end face in a length direction of the insulating base is L4; the second conductive layer has a minimum distance L5 from the second end face, wherein L4 is greater than L5.

In some examples of the present invention, a minimum distance of the first active material layer from the second end face in a length direction of the insulating substrate is L4'; the second active material layer has a minimum distance L5 ' from the second end face, wherein L4 ' is greater than L5 '.

In some examples of the invention, L5' is greater than L5 and the second conductive layer includes a second uncoated region for providing a second tab.

In some examples of the invention, the second tab is at a distance L6 from the second end face, and L6 is less than L4.

In some examples of the invention, the insulating matrix comprises one or more of polyimide, polyethylene, polyvinylidene fluoride, polytetrafluoroethylene.

In some examples of the invention, the first conductive layer comprises one or more of aluminum, titanium, stainless steel, aluminum alloys, and titanium alloys; the second conductive layer includes one or more of copper, titanium, nickel, a copper alloy, a nickel alloy, and a titanium alloy.

In some examples of the invention, the first active material layer includes one or more of lithium cobaltate, lithium manganate, lithium titanate, lithium iron phosphate, and lithium nickel cobalt manganate; the second active material layer comprises one or more of graphite, silicon, lithium titanate.

The battery cell comprises: the electrode plate is the electrode plate, and the electrode plate and the isolating film are wound.

The battery according to the present invention includes: electrolyte, packaging shell and electric core, electric core is foretell electric core.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a cross-sectional view of a pole piece according to an embodiment of the invention;

fig. 2 is a schematic view of a lamination of an insulating base, a first conductive layer, a second conductive layer, a first active material layer, and a second active material layer of a pole piece according to an embodiment of the present invention;

fig. 3 is a cross-sectional view of a cell according to an embodiment of the invention;

fig. 4 is a schematic view of a winding apparatus of a battery according to an embodiment of the present invention.

Reference numerals:

a pole piece 10;

an insulating base 1; a first surface 11; a second surface 12; a first end face 13; a second end face 14;

a first conductive layer 2; a first uncoated zone 21; a first tab 22;

a second conductive layer 3; a second uncoated zone 31; a second tab 32;

a first active material layer 4; a second active material layer 5; green glue 6;

a battery cell 20; an isolation film 201;

a winding device 30; a winding core 301; a first roller 302; a second roller 303;

a pole piece 10'; a first active substance 4'; a second active material 5'.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

A pole piece 10 of an embodiment of the present invention is described below with reference to fig. 1-4.

As shown in fig. 1 and 2, a pole piece 10 according to an embodiment of the present invention includes: an insulating substrate 1, a first conductive layer 2, a second conductive layer 3, a first active material layer 4, and a second active material layer 5. The insulating substrate 1 may include a first surface 11 and a second surface 12 disposed opposite to each other, and it should be noted that, as shown in fig. 1, the first conductive layer 2 is disposed on the first surface 11, the second conductive layer 3 is disposed on the second surface 12, the first active material layer 4 is disposed on the first conductive layer 2, and the second active material layer 5 is disposed on the second conductive layer 3. The polarity of the first active material layer 4 is opposite to that of the second active material layer 5, and it is to be explained that if the first active material layer 4 is a positive electrode active material layer, the second active material layer 5 is a negative electrode active material layer, and if the first active material layer 4 is a negative electrode active material layer, the second active material layer 5 is a positive electrode active material layer.

The insulating substrate 1, the first conducting layer 2, the second conducting layer 3, the first active material layer 4 and the second active material layer 5 are laminated together, so that a positive pole piece and a negative pole piece can be integrated on one pole piece 10, and the pole piece 10 has the characteristics of both the positive pole piece and the negative pole piece. In addition, the requirement on the winding equipment 30 of the battery can be reduced, and the positive pole piece and the negative pole piece are integrated together, so that the stability of the relative positions of the positive pole piece and the negative pole piece can be improved, the separated positive pole piece, the separated negative pole piece and the diaphragm can be prevented from being dislocated during winding, and the production yield of the battery can be improved. Meanwhile, by arranging the first conductive layer 2 and the second conductive layer 3 as current collectors on the insulating substrate 1, the mass of the pole piece 10 relative to the mass of a current collector using a conventional metal foil as a substrate can be reduced, and thus, the energy density of the battery can be improved.

In some embodiments of the present invention, the thickness of the insulating base 1 may be set to 6-8um, the thickness of each of the first conductive layer 2 and the second conductive layer 3 may be set to 2-3um, and the total thickness of the insulating base 1, the first conductive layer 2, and the second conductive layer 3 is 10-14 um. The first conductive layer 2 and the second conductive layer 3 can be respectively plated on the upper surface and the lower surface of the insulating base body 1 with the thickness of 6-8um by a magnetron sputtering method. The first conducting layer 2 and the second conducting layer 3 can be made of conducting metal, so that the relative thickness of the pole piece 10 and the existing pole piece can be reduced, and the volume energy density of the battery can be improved.

In some embodiments of the present invention, in the length direction of the insulating base 1 (i.e. the left-right direction in fig. 1), the insulating base 1 may include a first end face 13 and a second end face 14 which are oppositely arranged, the minimum distance between the first conductive layer 2 and the first end face 13 is L1, the minimum distance between the second conductive layer 3 and the first end face 13 is L2, and L2 is greater than L1, wherein when a tab is welded on the first conductive layer 2, the tab may be arranged close to the right end of the first conductive layer 2, such that the arrangement may enable the arrangement region of the tab and the second conductive layer 3 to have no overlapping region in the up-down direction, if a welding burr pierces through the insulating base 1, the first conductive layer 2 and the second conductive layer 3 may be prevented from conducting, such that the risk of short circuit of the pole piece 10 may be reduced, and the safety in use of the pole piece 10 may be.

In some embodiments of the present invention, as shown in fig. 1, in the length direction of the insulating substrate 1, the minimum distance between the first active material layer 4 and the first end surface 13 is L1 ', the minimum distance between the second active material layer 5 and the first end surface 13 is L2', and L2 'is greater than L1'.

In some embodiments of the present invention, as shown in fig. 1, the first conductive layer 2 may include: a first uncoated zone 21, the first uncoated zone 21 may be used to provide a first tab 22. Wherein L1' is larger than L1, so that the formation of the first uncoated region 21 on the right side of the first active material layer 4 can be ensured and the welding position of the first tab 22 can be ensured. And set up L2 simultaneously and be greater than L1, can guarantee that the second conducting layer 3 and second active substance layer 5 are not set up in the region relative with first utmost point ear 22 on the second surface 12 of insulating base member 1, can avoid the condition emergence that welding burr causes the internal short circuit of pole piece 10 after impaling insulating base member 1 to can improve the security performance of pole piece 10.

In some embodiments of the present invention, as shown in fig. 1, the distance between the first tab 22 and the first end surface 13 may be set to L3, and L3 is smaller than L2, wherein the distance between the leftmost end of the first tab 22 and the first end surface 13 may be set to L3, which can further ensure that the second conductive layer 3 and the second active material layer 5 are not disposed on the region of the second surface 12 of the insulating base 1 opposite to the first tab 22, so as to better avoid occurrence of a short circuit inside the pole piece 10 after a welding burr penetrates the insulating base 1, thereby further improving the safety performance of the pole piece 10.

In some embodiments of the present invention, as shown in fig. 1, in the length direction of the insulating base 1, the minimum distance between the first conductive layer 2 and the second end surface 14 may be set to be L4, the minimum distance between the second conductive layer 3 and the second end surface 14 may be set to be L5, and L4 is greater than L5, wherein, when a tab is welded on the second conductive layer 3, the tab may be disposed near the left end of the second conductive layer 3, such that the disposed region of the tab and the first conductive layer 2 do not overlap in the up-down direction, if a welding burr pierces through the insulating base 1, the first conductive layer 2 and the second conductive layer 3 may be prevented from conducting, so that the risk of short circuit of the pole piece 10 may be reduced, and the safety in use of the pole piece 10 may be improved.

In some embodiments of the present invention, as shown in fig. 1, in the length direction of the insulating substrate 1, the minimum distance of the first active material layer 4 from the second end face 14 may be set to L4 ', the minimum distance of the second active material layer 5 from the second end face 14 may be set to L5', and L4 'is greater than L5'.

In some embodiments of the present invention, as shown in fig. 1, the second conductive layer 3 may include: a second uncoated zone 31, the second uncoated zone 31 may be used to provide a second tab 32. Where L5' is larger than L5, this arrangement ensures that the second uncoated region 31 is formed on the left side of the second active material layer 5 and the bonding position of the second tab 32 is ensured.

In some embodiments of the present invention, the distance between the second tab 32 and the second end face 14 may be set to L6, and L6 is smaller than L4, where L6 is the distance between the rightmost end of the second tab 32 and the second end face 14, which can further ensure that the first conductive layer 2 and the first active material layer 4 are not disposed in the region of the first surface 11 of the insulating base 1 opposite to the first tab 22, so as to better avoid the occurrence of a short circuit inside the pole piece 10 after the welding burr pierces the insulating base 1, thereby further improving the safety performance of the pole piece 10.

In some embodiments of the present invention, the insulating base 1 may include: one or more of polyimide, polyethylene, polyvinylidene fluoride and polytetrafluoroethylene are arranged, so that the manufacturing material of the insulating base body 1 is an insulating organic material, the metal content of the pole piece 10 can be further reduced, the light-weight design of the pole piece 10 can be realized, and the mass energy density of the pole piece 10 can be further improved.

In some embodiments of the present invention, when the first conductive layer 2 is a positive conductive layer, the first conductive layer 2 may include one or more of aluminum, titanium, stainless steel, aluminum alloy and titanium alloy, and when the second conductive layer 3 is a negative conductive layer, the second conductive layer 3 may include one or more of copper, titanium, nickel, copper alloy, nickel alloy and titanium alloy, such an arrangement may enable the manufacturing materials of the first conductive layer 2 and the second conductive layer 3 to be more reasonable, may ensure the working performance of the first conductive layer 2 and the second conductive layer 3, and, by disposing the first conductive layer 2 and the second conductive layer 3 on the insulating base 1 in a thin film plating manner, may reduce the amount of metal materials used, and may better improve the quality energy density of the pole piece 10.

In some embodiments of the present invention, when the first active material layer 4 is a positive electrode active material, the first active material layer 4 may include one or more of lithium cobaltate, lithium manganate, lithium titanate, lithium iron phosphate, and lithium nickel cobalt manganese, and when the second active material layer 5 is a negative electrode active material, the second active material layer 5 may include one or more of graphite, silicon, and lithium titanate. The positive pole piece and the negative pole piece are integrated on one pole piece 10, so that the proportion of the active material in the pole piece 10 can be increased, and the volume energy density of the battery can be increased.

As shown in fig. 3, the battery cell 20 according to the embodiment of the present invention includes: a separator 201 and a pole piece 10. The pole piece 10 may be provided as the pole piece 10 of the above embodiment, and the pole piece 10 is wound around the separator 201. Through a conventional winding process, one pole piece 10 and one isolation film 201 can be wound into a single battery cell 20, so that the usage amount of the isolation film 201 can be reduced, the active material proportion can be increased, and the volume energy density of the battery cell 20 can be improved. Moreover, the applied pole piece 10 has low requirements on the winding device 30, and the pole piece 10 of the present application can improve the problem of dislocation of the positive pole piece and the negative pole piece during winding, and can improve the production yield and efficiency of the battery cell 20, thereby reducing the production cost of the battery cell 20.

In some embodiments of the present invention, the length and width of the first and second conductive layers 2 and 3 may be determined according to the welding position of the tab. As shown in fig. 1, the right end and the left end of the first active material layer 4 can both be provided with the green glue 6, the distance from the green glue 6 at the right end of the first active material layer 4 to the first end face 13 is smaller than the distance from the right end of the first conductive layer 2 to the first end face 13, so that the green glue 6 covers the first tab 22, thereby preventing the welding burr from piercing the pole piece 10 and further reducing the risk of thermal runaway of the battery cell 20.

In some embodiments of the present invention, as shown in fig. 1, the green glue 6 may be disposed at the left end of the second active material layer 5, where a distance between the green glue 6 and the second end surface 14 may be greater than a distance between the second conductive layer 3 and the second end surface 14, so that the green glue 6 covers the second tab 32, thereby preventing a soldering burr from piercing the tab 10, and further reducing a risk of thermal runaway occurring in the battery cell 20.

In some embodiments of the present invention, as shown in fig. 4, the winding apparatus 30 may include: roll up core 301, first roller 302 and second roller 303, first roller 302 can be pole piece 10 unreel roller, second roller 303 can be barrier film 201 unreel roller, pole piece 10 and barrier film 201 roll up into single electric core 20 (as shown in fig. 3) through rolling up core 301, when single pole piece 10 is convoluteed, the dislocation is easy to be controlled, can reduce the goodness loss that causes because of positive pole piece, negative pole piece dislocation to can improve the product goodness, reduce the manufacturing cost of electric core 20.

A battery according to an embodiment of the present invention includes: electrolyte, package, and cell 20. The battery cell 20 may be configured as the battery cell 20 according to the above embodiment, and such configuration may improve energy density of the battery, reduce risk of short circuit in the battery, and also improve safety performance of the battery.

In some embodiments of the present invention, since the length and width of the first conductive layer 2 and the second conductive layer 3 are controllable, when the pole piece 10 is cut, the metal coating can be avoided, and only the insulating substrate 1 is cut, as shown in fig. 1, the cutting positions are all made of insulating materials, and cutting is performed at positions away from the metal material position, so that cutting burrs can be effectively controlled, the K value of the battery can be improved, and the safety performance of the battery can be improved. It should be explained that: the cutting position refers to the area of the insulating substrate 1 which is not coated with any substance, the K value of the battery refers to the voltage drop of the battery in unit time, and the K value is an index for measuring the self-discharge rate of the lithium battery.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.