阅读说明：本技术 叠片式电芯及其制备方法 (Laminated battery cell and preparation method thereof ) 是由 陈周昊 李明 于 2021-08-04 设计创作，主要内容包括：本发明提供叠片式电芯及其制备方法。本发明的叠片式电芯包括第一极片和第二极片,所述第一极片由两层连续的隔膜和位于所述两层连续的隔膜之间的上下表面间歇性涂覆有正极材料或负极材料的连续的集流体复合而成,所述第二极片为负极单片或正极单片。本发明改善了现有叠片工艺制备电芯过程中正负极易错位、叠片过程张力不均隔膜易褶皱的问题,同时无需对叠片后的极组进行热压定型,无需同时使用正负极单片,从而有效提升电池制造过程的稳定性和安全性,降低生产成本,提高生产效率。(The invention provides a laminated battery cell and a preparation method thereof. The laminated battery cell comprises a first pole piece and a second pole piece, wherein the first pole piece is formed by compounding two layers of continuous diaphragms and continuous current collectors which are positioned between the two layers of continuous diaphragms and the upper and lower surfaces of which are intermittently coated with positive electrode materials or negative electrode materials, and the second pole piece is a negative electrode single piece or a positive electrode single piece. The invention improves the problems that the positive and negative are easy to misplace in the process of preparing the battery core by the existing lamination process, and the diaphragm is easy to wrinkle due to uneven tension in the lamination process, and simultaneously, the hot-press shaping of the laminated pole group is not needed, and the use of positive and negative single pieces is not needed, so that the stability and the safety of the battery manufacturing process are effectively improved, the production cost is reduced, and the production efficiency is improved.)

1. The utility model provides a lamination formula electricity core, its characterized in that, lamination formula electricity core includes first pole piece and second pole piece, first pole piece by two-layer continuous diaphragm with be located the continuous mass flow body complex that upper and lower surface intermittent type nature between the two-layer continuous diaphragm coated with positive electrode material or negative electrode material forms, the second pole piece is negative pole monolithic or positive pole monolithic.

2. The laminated cell of claim 1,

in the first pole piece, the positive electrode material or the negative electrode material is intermittently coated on the continuous current collector in an equal-gap or unequal-gap mode; and/or

First pole piece still contains the rubber coating, the rubber coating is located two upper and lower surfaces of uncoated positive electrode material or negative electrode material part on the mass flow body with be located the mass flow body both sides between the continuous diaphragm.

3. The laminated cell of claim 1, wherein the laminated cell is a zigzag laminated cell and/or a wound laminated cell.

4. A method of making a laminated cell, comprising the steps of:

(1) providing a continuous current collector, a continuous diaphragm and a negative single sheet, wherein the upper surface and the lower surface of the continuous current collector, the continuous diaphragm and the negative single sheet are intermittently coated with a positive electrode material, or the continuous current collector, the continuous diaphragm and the positive single sheet are intermittently coated with a negative electrode material;

(2) gluing the upper surface and the lower surface of the part, which is not coated with the anode material or the cathode material, of the current collector;

(3) compounding and fixing the current collector processed in the step (2) and a diaphragm which is arranged on the upper surface and the lower surface of the current collector and is conveyed at the gluing position through hot pressing to form a first pole piece;

(4) and (4) laminating the first pole piece obtained in the step (3) with the negative pole single piece or the positive pole single piece to form a laminated battery cell.

5. The method as claimed in claim 4, wherein in the step (3), the temperature of the hot pressing is 80-100 ℃ and/or the pressure of the hot pressing is 100-1000 kg.

6. The method according to claim 4, wherein in the step (3), the hot pressing is performed by using a rolling manner.

7. The method of claim 4, wherein in step (4), the lamination is in the form of zigzag lamination and/or wound lamination.

8. The method according to claim 4, wherein in the first pole piece, the positive electrode material or the negative electrode material is intermittently coated on the continuous current collector in an equal interval or an unequal interval mode.

9. A laminated cell prepared by the method of any of claims 4-8.

10. A laminated lithium ion battery, characterized in that it comprises a laminated cell according to any of claims 1 to 3 and 9.

Technical Field

The invention belongs to the field of batteries, and particularly relates to a laminated battery cell and a preparation method thereof.

Background

The lamination process is a common battery pole group forming mode, generally continuous positive pole pieces and negative pole pieces are cut into single pieces after being subjected to die cutting, and then the positive pole pieces and the negative pole pieces are alternately placed on a Z-shaped folded diaphragm to be stacked to form a bare cell. However, such a process has the following problems: the positive electrode and the negative electrode need to be cut off respectively to form single pieces, so that the risk of burrs generated in the machining process is high; dislocation is easy to occur between the anode single sheet and the cathode single sheet and between the anode and the cathode and the diaphragm in the lamination process, so that poor alignment is caused; the diaphragm is light and thin in texture, and unreels and to be realized by equipment application tension in the folding mode of zigzag motion, easily produces the fold defect. In addition, after lamination, the pole group sometimes needs to be subjected to hot press molding to reduce the risk of displacement or dislocation between the pole piece and the diaphragm, between the positive pole piece and the negative pole piece, and between layers.

The lithium ion battery has the characteristics of high specific capacity, small self-discharge, wide working temperature range, high voltage platform, long cycle life, no memory effect, environmental friendliness and the like, and is widely applied to the fields of electric vehicles, energy storage, digital electronic products and the like. The laminated cell is widely applied to lithium ion batteries. The above-mentioned problems of the conventional laminated cell and lamination process have a great influence on the cost of the laminated ion battery and the stability, safety and production efficiency of the manufacturing process.

Therefore, there is a need in the art for a laminated cell and a method for manufacturing the same, which can effectively improve the stability and safety of the battery manufacturing process, reduce the production cost, and improve the production efficiency.

Disclosure of Invention

The invention aims to provide a laminated cell and a preparation method thereof, which solve the problems that positive and negative electrodes are easy to misplace in the cell preparation process and a diaphragm is easy to wrinkle due to uneven tension in the lamination process in the existing lamination process, and simultaneously, a laminated pole group is not required to be subjected to hot-press forming, and positive and negative single plates are not required to be used simultaneously, so that the stability and the safety of the battery manufacturing process are effectively improved, the production cost is reduced, and the production efficiency is improved.

Specifically, the invention provides a laminated battery cell, which comprises a first pole piece and a second pole piece, wherein the first pole piece is formed by compounding two continuous diaphragms and continuous current collectors, the upper surfaces and the lower surfaces of the two continuous diaphragms are intermittently coated with positive electrode materials or negative electrode materials, and the second pole piece is a negative electrode single piece or a positive electrode single piece.

In one or more embodiments, in the first pole piece, the positive electrode material or the negative electrode material is intermittently coated on the continuous current collector in the form of equal gaps or unequal gaps.

In one or more embodiments, the first pole piece further comprises a glue coating layer, the glue coating layer is located on the current collector, the upper surface and the lower surface of the part of the uncoated positive electrode material or negative electrode material are located on the current collector, and the glue coating layer is located between the continuous diaphragms on the two sides of the current collector.

In one or more embodiments, the laminated cell is a zigzag laminated cell and/or a wound laminated cell.

The invention also provides a method for preparing a laminated cell, which comprises the following steps:

(1) providing a continuous current collector, a continuous diaphragm and a negative single sheet, wherein the upper surface and the lower surface of the continuous current collector, the continuous diaphragm and the negative single sheet are intermittently coated with a positive electrode material, or the continuous current collector, the continuous diaphragm and the positive single sheet are intermittently coated with a negative electrode material;

(2) gluing the upper surface and the lower surface of the part, which is not coated with the anode material or the cathode material, of the current collector;

(3) compounding and fixing the current collector processed in the step (2) and a diaphragm which is arranged on the upper surface and the lower surface of the current collector and is conveyed at the gluing position through hot pressing to form a first pole piece;

(4) and (4) laminating the first pole piece obtained in the step (3) with the negative pole single piece or the positive pole single piece to form a laminated battery cell.

In one or more embodiments, the temperature of the hot pressing in step (3) is from 80 to 100 ℃.

In one or more embodiments, the pressure of the hot press in step (3) is 100-.

In one or more embodiments, in step (3), the hot pressing is performed using a rolling manner.

In one or more embodiments, in step (4), the manner of lamination is zigzag lamination and/or wound lamination.

In one or more embodiments, in the first pole piece, the positive electrode material or the negative electrode material is intermittently coated on the continuous current collector in the form of equal gaps or unequal gaps.

The invention also provides a laminated cell prepared by the method of any embodiment of the invention.

The invention also provides a laminated lithium ion battery, which is characterized by comprising the laminated cell in any embodiment of the invention.

Drawings

Fig. 1 is a schematic view of a process of compounding a separator with a current collector intermittently coated with a positive electrode material or a negative electrode material in some embodiments of the present invention.

Fig. 2 is a schematic view of a glue coated area on a current collector intermittently coated with a positive or negative electrode material according to some embodiments of the present invention.

Fig. 3 is a structural diagram of a cell obtained by stacking a composite negative plate and a positive plate in a Z-shape according to some embodiments of the present invention.

Fig. 4 is a structural diagram of a cell obtained by laminating a composite negative electrode sheet and a positive electrode sheet in a winding manner according to some embodiments of the invention.

Fig. 5 is a schematic diagram of a cell formed by stacking a composite positive plate and a negative plate in a Z-shape according to some embodiments of the invention.

Fig. 6 is a schematic diagram of a cell obtained by laminating a composite positive plate and a negative plate in a winding manner according to some embodiments of the invention.

In fig. 1 to 6, 1 is a current collector intermittently coated with a positive electrode material or a negative electrode material; 2 is a glue coating area on the current collector intermittently coated with the anode material or the cathode material; 3 is a gluing device; 41 is a diaphragm on the upper surface of the pole piece; 42 is a diaphragm on the lower surface of the pole piece; 51 is a metal upper press roll; 52 is a metal lower pressure roller; and 6 is a composite electrode plate.

Detailed Description

To make the features and effects of the present invention comprehensible to those skilled in the art, general description and definitions are made below with reference to terms and expressions mentioned in the specification and claims. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

The theory or mechanism described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, i.e., the present disclosure may be practiced without limitation to any particular theory or mechanism.

All features defined herein as numerical ranges or percentage ranges, such as numbers, amounts, levels and concentrations, are for brevity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered to cover and specifically disclose all possible subranges and individual numerical values (including integers and fractions) within the range.

Herein, when embodiments or examples are described, it is to be understood that they are not intended to limit the invention to these embodiments or examples. On the contrary, all alternatives, modifications, and equivalents of the methods and materials described herein are intended to be included within the scope of the invention as defined by the appended claims.

In this context, for the sake of brevity, not all possible combinations of features in the various embodiments or examples are described. Therefore, the respective features in the respective embodiments or examples may be arbitrarily combined as long as there is no contradiction between the combinations of the features, and all the possible combinations should be considered as the scope of the present specification.

The laminated battery cell comprises a first pole piece and a second pole piece. The laminated cell of the present invention may be used as a lithium ion battery cell or a primary battery cell.

In the invention, the first pole piece (also called composite electrode piece) is compounded by two layers of continuous diaphragms and continuous current collectors which are positioned between the two layers of continuous diaphragms and the upper and lower surfaces of which are intermittently coated with positive electrode materials or negative electrode materials. In the present invention, the composite electrode sheet containing the positive electrode material is referred to as a composite positive electrode sheet, and the composite electrode sheet containing the negative electrode material is referred to as a composite negative electrode sheet. In the composite electrode plate, the continuous current collector with the upper and lower surfaces intermittently coated with the positive electrode material or the negative electrode material can be regarded as a continuous electrode plate with the positive electrode material or the negative electrode material intermittently coated.

In the invention, the second pole piece is a negative pole single piece and a positive pole single piece used in the conventional lamination process. Specifically, the negative electrode single sheet and the positive electrode single sheet respectively refer to a discontinuous negative electrode sheet and a discontinuous positive electrode sheet alternately disposed between layers of a layered structure formed by zigzag folding or winding a separator in a conventional lamination process. It can be understood that, in the present invention, when the first electrode sheet is a composite positive electrode sheet, the second electrode sheet is a negative electrode sheet, and when the first electrode sheet is a composite negative electrode sheet, the second electrode sheet is a positive electrode sheet.

It is to be understood that, in the present invention, "continuous" means that the materials described remain connected in the formed battery pole group. In the laminated cell of the present invention, the second pole piece is located between layers of a multilayer structure formed by folding and/or winding the first pole piece.

In the invention, the term "intermittent coating" refers to that segments of the positive electrode material or the negative electrode material coated along the length direction of the current collector are spaced at a certain distance. The size of each segment of positive or negative electrode material coated on the current collector generally corresponds to the size of the second pole piece. In the invention, the term "equal gaps" means that the distances among the sections of the positive electrode material or the negative electrode material coated on the current collector are equal, and the term "unequal gaps" means that the distances among the sections of the positive electrode material or the negative electrode material coated on the current collector are unequal.

The laminated battery cell can be a Z-shaped laminated battery cell, a winding-type laminated battery cell or a Z-shaped winding combined type laminated battery cell. As shown in fig. 3 and 5, in the zigzag laminated cell of the present invention, the second electrode sheet is disposed between layers of a multilayer structure formed by zigzag folding a composite electrode sheet intermittently coated with a positive electrode material or a negative electrode material at equal intervals. As shown in fig. 4 and 6, in the winding type laminated cell of the present invention, the second electrode sheet is disposed between layers of a multilayer structure formed by winding a composite electrode sheet intermittently coated with a positive electrode material or a negative electrode material at unequal intervals. In the invention, the zigzag winding combined type laminated battery cell refers to a battery cell formed by laminating a first pole piece and a second pole piece in zigzag folding and winding modes. For example, the zigzag wound composite laminated cell of the present invention may be formed by connecting the zigzag laminated cell of the present invention and a wound laminated cell by a continuous first stage sheet.

In the composite electrode plate, two continuous separators and continuous current collectors which are positioned between the two continuous separators and have the upper and lower surfaces intermittently coated with the positive electrode material or the negative electrode material can be compounded in an adhesive mode. As shown in fig. 2, a portion of the current collector not coated with the positive electrode material or the negative electrode material (i.e., the gap position) may serve as a rubberized area. After the upper surface and the lower surface of the current collector gluing area are glued, the current collector intermittently coated with the positive electrode material or the negative electrode material and the diaphragm positioned on the upper surface and the lower surface of the current collector can be rolled by using a hot-pressing roller, so that the current collector and the diaphragm are bonded. The adhesive coated on the glue coating area can be selected from polyvinylidene fluoride, acrylic ester, synthetic rubber and the like.

In the present invention, the positive electrode material in the composite positive electrode sheet and the positive electrode material in the positive electrode single sheet are not particularly limited. The positive electrode material generally includes a positive electrode active material, a conductive agent, and a binder. The positive active material in the positive material may be one or more selected from lithium iron phosphate, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminate, lithium manganese oxide and lithium cobalt oxide. In some embodiments, the positive electrode active material is lithium nickel cobalt manganese oxide. The conductive agent in the positive electrode material may be one or more selected from conductive carbon black, carbon fiber, acetylene black, conductive graphite, graphene, carbon nanotubes, and carbon microspheres. The binder in the positive electrode material may be one or more selected from the group consisting of polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl alcohol, polyolefin, styrene-butadiene rubber, fluorinated rubber, polyurethane, and sodium alginate. The proportions of the positive electrode active material, the conductive agent and the binder in the positive electrode material may be conventional in the art.

In the present invention, the negative electrode material in the composite negative electrode sheet and the negative electrode material in the negative electrode single sheet are not particularly limited. The anode material generally includes an anode active material, a conductive agent, and a binder. The negative electrode active material in the negative electrode material may be one or more selected from graphite, silicon carbon, silicon monoxide, and lithium titanate. In some embodiments, the negative active material is graphite. The conductive agent in the negative electrode material may be one or more selected from conductive carbon black, carbon fiber, acetylene black, conductive graphite, graphene, carbon nanotubes, and carbon microspheres. The binder in the negative electrode material may be one or more selected from the group consisting of polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl alcohol, polyolefin, sodium carboxymethylcellulose, styrene-butadiene rubber, fluorinated rubber, polyurethane, and sodium alginate. The proportions of the negative electrode active material, the conductive agent and the binder in the negative electrode material may be conventional in the art.

In the present invention, the current collector in the composite electrode sheet is not particularly limited, and may be a copper foil, an aluminum foil, a titanium foil, a nickel foil, an iron foil, or a zinc foil. In some embodiments, the current collector in the composite positive electrode sheet is an aluminum foil. In some embodiments, the current collector in the composite negative electrode sheet is a copper foil.

In the present invention, the separator in the composite electrode sheet is not particularly limited, and may be a polyethylene film, a polypropylene film, a ceramic-coated polypropylene separator, a ceramic-coated polyethylene separator, a polypropylene/polyethylene double-layer separator, a polypropylene/polyethylene/polypropylene three-layer separator, a polypropylene/polypropylene double-layer separator, or the like.

The laminated cell can be prepared by adopting a method comprising the following steps:

(1) providing a continuous current collector, a continuous diaphragm and a negative single sheet with the upper and lower surfaces intermittently coated with a positive electrode material, and a continuous diaphragm, or providing a continuous current collector, a continuous diaphragm and a positive single sheet with the upper and lower surfaces intermittently coated with a negative electrode material;

(2) gluing the upper and lower surfaces of the part, which is not coated with the positive electrode material or the negative electrode material, of the continuous current collector with the upper and lower surfaces intermittently coated with the positive electrode material or the negative electrode material;

(3) compounding and fixing the continuous current collector with the upper and lower surfaces intermittently coated with the positive electrode material or the negative electrode material and the continuous diaphragm on the upper and lower surfaces for conveying in the step (2) at the gluing position through hot pressing to form a composite electrode plate;

(4) and (4) laminating the composite electrode slice obtained in the step (3) with a negative electrode single slice or a positive electrode single slice to form the battery cell.

In some embodiments, in the step (3), the continuous current collector with the upper and lower surfaces intermittently coated with the positive electrode material or the negative electrode material after the treatment of the step (2) and the continuous separator disposed on the upper and lower surfaces are heated and pressed by a hot press roller to perform the thermocompression bonding, wherein the heating temperature is preferably 80 to 100 ℃, and the pressure is preferably 100 + 1000kg, such as 500 ± 100 kg. Controlling the heating temperature and pressure within the aforementioned ranges facilitates rapid and robust compounding between the current collector and the separator. The rolling mode is adopted for compounding, so that the stability and continuity of the compounding process are ensured, and the continuous production is realized. The heated press roll may be a metal roll. In some embodiments, the heated press rolls include a metal upper press roll and a metal lower press roll.

In some embodiments, in the step (4), the composite electrode plate obtained in the step (3) and the negative electrode single sheet or the positive electrode single sheet are laminated in a zigzag manner and/or in a winding manner to form a battery cell.

In some embodiments, the method of making a laminated cell of the present invention does not include the step of thermoforming the cell.

In some embodiments, as shown in fig. 1, the process of compounding the separator with the current collector intermittently coated with the positive electrode material or the negative electrode material includes the steps of gluing the upper and lower surfaces of the gluing area 2 of the current collector 1 intermittently coated with the positive electrode material or the negative electrode material while passing through the gluing device 3, arranging the pole piece upper surface separator 41 and the pole piece lower surface separator 42 on the upper and lower surfaces of the glued current collector 1 intermittently coated with the positive electrode material or the negative electrode material, respectively, and performing thermocompression bonding under the action of the metal upper pressing roller 51 and the metal lower pressing roller 52 to form the composite electrode sheet 6.

The laminated battery cell can be used for batteries suitable for various laminated battery cells, such as laminated lithium ion batteries, primary batteries and the like. The invention comprises a laminated lithium ion battery comprising the laminated cell. The laminated lithium ion battery generally comprises a battery core,The electrolyte and the shell can be formed by filling the battery cell into the shell and performing one or more steps selected from baking, liquid injection, sealing, chemical formation and partial volume. The conditions of baking, formation and volume division can be conventional in the art. The electrolyte typically contains a solvent, an additive, and a lithium salt. The solvent in the electrolyte may be one or more selected from dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, ethylene carbonate and propylene carbonate. The additive in the electrolyte may be selected from one or more of fluoroethylene carbonate, vinylene carbonate, 1,3 propane sultone and ethylene carbonate. The lithium salt in the electrolyte may be selected from lithium iron phosphate and LiPF₆LiFSI, LiTFSI, LiBOB, LiODFB and LiBF₄One or more of (a).

The beneficial effects of the invention include: the diaphragm and the current collector intermittently coated with the positive electrode material or the negative electrode material are compounded to form the composite electrode plate, the pole pieces and the diaphragm are well fixed, only the relative positions of the composite positive plate and the negative single plate or the composite negative plate and the positive single plate are required to be controlled in the assembling process, poor alignment caused by displacement and dislocation between the positive and negative pole pieces and between the pole pieces and the diaphragm is reduced, and extra hot-pressing shaping is not required to be carried out on a pole group after lamination. The composite electrode plate formed by compounding the diaphragm and the pole piece reduces the risk of generating wrinkles in the lamination process. Because only one of the positive electrode single sheet or the negative electrode single sheet is used, the burr risk in the production process of the pole piece is obviously reduced.

Compared with the conventional lamination process, the method has the following advantages:

1. the conventional lamination process needs to use both the anode single sheet and the cathode single sheet, the anode and the cathode need to be cut off respectively to form the single sheets, and the risk of generating burrs in the cutting process of the single sheets is high.

2. The conventional lamination process needs equipment to apply tension to the diaphragm, the diaphragm is uncoiled and folded in a Z shape, and the diaphragm is light and thin in texture and free of support, so that wrinkle defects are easily caused by fluctuation in the process and introduced into a battery cell.

3. The conventional lamination process needs to control the relative position between the negative plate and the diaphragm, and between the negative plate and the positive plate at the same time, and has extremely high requirements on the process capability of the lamination process.

4. The current collector of the composite electrode plate is intermittently coated with the positive and negative electrode materials, so that a current collector area which is partially not coated with the positive and negative electrode materials is reserved and is used as a Z-shaped folding bending area and/or an arc-shaped area of a winding lamination. The positive and negative electrode materials in the bending area and the arc area can increase the weight of the battery, and the energy density of the battery cannot be effectively improved. Therefore, the invention saves the anode and cathode materials and avoids the working procedure of scraping the anode and cathode materials in the bent area and/or the arc area of the current collector.

The present invention will be illustrated below by way of specific examples. It should be understood that these examples are illustrative only and are not intended to limit the scope of the present invention. The methods, reagents and materials used in the examples are, unless otherwise indicated, conventional in the art. The reagents and materials in the examples are all commercially available.

Example 1

Referring to fig. 1 to 3, in the present embodiment, a gluing area 2 of a current collector 1 intermittently coated with graphite at equal intervals is glued by a gluing device 3, and is thermally bonded with a diaphragm 41 and a diaphragm 42 which are arranged on the upper and lower surfaces of the current collector at a metal pressing roll, wherein the temperature of the metal pressing roll is adjusted to 80 ℃, and the pressure is 500 kg. And (4) obtaining the composite negative plate compounded by the diaphragm and the current collector intermittently coated with graphite in equal gaps after hot-pressing bonding. And (3) laminating the composite negative plate and the cut nickel cobalt lithium manganate positive single plate in a Z shape to form the lithium ion battery core shown in figure 3.

Example 2

Referring to fig. 1, 2 and 4, in the present embodiment, a gluing area 2 of a current collector 1 intermittently coated with graphite at unequal gaps is glued by a gluing device 3, and is thermally and pressure bonded with a diaphragm 41 and a diaphragm 42 arranged on the upper and lower surfaces of the current collector at a metal pressing roll, wherein the temperature of the metal pressing roll is adjusted to 80 ℃, and the pressure is 500 kg. And (4) obtaining the composite negative plate compounded by the diaphragm and the current collector intermittently coated with graphite in the non-equal gap after hot-pressing bonding. And (3) performing winding lamination on the composite negative plate and the cut nickel cobalt lithium manganate positive single plate to form the lithium ion battery core shown in fig. 4.

Example 3

Referring to fig. 1, 2 and 5, in the embodiment, the glue coating area 2 of the current collector 1 intermittently coated with nickel cobalt lithium manganate at equal gaps is coated with glue by the glue coating device 3, and the current collector is hot-pressed and bonded with the diaphragm 41 and the diaphragm 42 which are arranged on the upper surface and the lower surface of the current collector at a metal pressing roller, wherein the temperature of the metal pressing roller is adjusted to 80 ℃, and the pressure is 500 kg. And (4) obtaining a composite positive plate compounded by the diaphragm and the current collector intermittently coated with the nickel cobalt lithium manganate in an equal gap after hot-pressing bonding. And (3) laminating the composite positive plate and the cut graphite negative single plate in a Z shape to form the lithium ion battery cell shown in the figure 5.

Example 4

Referring to fig. 1, 2 and 6, in the embodiment, the glue coating area 2 of the current collector 1 intermittently coated with nickel cobalt lithium manganate at unequal gaps is coated with glue by the glue coating device 3, and the current collector is hot-pressed and bonded with the diaphragm 41 and the diaphragm 42 which are arranged on the upper surface and the lower surface of the current collector at a metal pressing roller, wherein the temperature of the metal pressing roller is adjusted to 80 ℃, and the pressure is 500 kg. And (4) obtaining a composite positive plate compounded by the diaphragm and the current collector intermittently coated with nickel cobalt lithium manganate in the unequal gap after hot-pressing bonding. And (3) performing winding lamination on the composite positive plate and the cut graphite negative single plate to form the lithium ion battery cell shown in fig. 6.