WO2019242668A1

WO2019242668A1 - Lithium ion battery and assembly method therefor

Info

Publication number: WO2019242668A1
Application number: PCT/CN2019/092000
Authority: WO
Inventors: 丁希罕; 金明钢; 王瑞奔; 叶枭; 韩改格; 刘其达
Original assignee: 杭州天丰电源股份有限公司
Priority date: 2018-06-22
Filing date: 2019-06-20
Publication date: 2019-12-26
Also published as: CN108933280B; CN108933280A

Abstract

The present invention relates to the field of lithium ion batteries and sets forth a lithium ion battery and an assembly method therefor. With regard to the problem in the existing technology wherein battery costs increase as a result of battery cell expansion, the following technical solution is employed: a lithium ion battery, comprising a support and a battery housing that accommodates the support, wherein the support comprises an accommodating chamber and a top cover, a plurality of plate-shaped battery cells are vertically placed in the accommodating chamber and are sequentially stacked horizontally, and side walls of the accommodating chamber are pressed tight by a pressing band so that the pressing direction is consistent with the cell stacking direction. Such a structure is beneficial in achieving rapid assembly and saving manufacturing costs. The assembly method for a lithium ion battery comprises the following: step 1, assembling cells and combination plates in an accommodating chamber; step 2, assembling a pressing band; step 3, assembling a top cover; step 4, assembling a support in a housing body; step 5, fixing a cover body onto the housing body. Such a method may reduce the impact of rapid loss of battery cell capacity as a result of the uneven distribution of current density, and extend the storage life of lithium ion batteries at high temperatures.

Description

Lithium-ion battery and assembly method thereof

Technical field

The invention belongs to the field of lithium batteries, and particularly relates to a lithium ion battery and an assembly method thereof.

Background technique

The existing lithium-ion battery is provided with a cell group composed of a plurality of cells. The cell group is vertically mounted on a bracket. The plurality of cells generate more heat during the charging and discharging process, and the heat is easily accumulated. And the bracket has a limited limitation on the battery cells. The battery cells are prone to volume expansion and bulging. After the battery cells are swollen, they will cause poor contact of the pole pieces of the battery cells, which will accelerate the loss of battery capacity, which not only affects the battery cell The storage life will also damage the stability of the lithium-ion battery structure and affect the use of lithium-ion batteries. However, when the battery cell is improved by improving the structure or material of the battery itself, it takes a long time to develop, which will lead to the lithium-ion battery. The cost is higher and the production cycle becomes longer.

Summary of the Invention

Aiming at solving the problem of battery cost increase caused by cell bulging in the prior art, the present invention provides a lithium ion battery, which can improve the cell bulging condition by improving the assembly structure of the cell, which can save costs and provide an assembly method thereof. The assembly method has the advantages of saving time and labor, and also has the effect of extending the storage life of the lithium ion battery under high temperature conditions.

The technical solution adopted by the present invention is as follows: A lithium-ion battery includes a bracket for assembling a battery cell and a battery case for containing the bracket. The bracket includes a receiving cavity for receiving the battery cell and is fixed on the upper part of the receiving cavity. A plurality of plate-shaped battery cells are vertically placed in the receiving cavity, and stacked laterally in sequence. The tabs on the upper end of each battery cell are fixed on the upper cover, and the side wall of the receiving cavity is at least A closed pressing belt is pressed so that the direction in which the side wall of the accommodating cavity presses the battery cells is the same as the direction in which the battery cells are stacked.

The compression band presses the side wall of the accommodating cavity inward, so that the stacked battery cells are compressed, so as to reduce the adverse effects caused by the bulging of the battery cells. The compression band is conducive to achieving rapid assembly and saving production costs.

Further, the accommodating cavity is a box-shaped cavity with a closed bottom, and its side wall includes two oppositely disposed thin walls with slightly deformable parts, and a combination plate is provided between the thin wall and the battery core, and the combination plate It consists of a plastic plate that is in close contact with the battery cell and a metal plate that is in close contact with the thin wall. A compression plate is provided between the compression belt and the thin wall. The compression plate is pressed by the compression belt to make the thin The slightly deformable part of the wall is changed from convex to concave to stick to the combination board to compact the battery core. The slightly deformable part is a convex structure before the battery cell is assembled, and the assembly space is reserved for the battery cell to avoid mutual interference between the cells. After the battery cell is assembled, the slightly deformable part is compressed by the compression plate. Outward convexity becomes inward concave, which causes local stress. The combination board is used to protect the battery core, the metal plate prevents the battery core from being crushed, and the plastic plate is insulated from the battery core.

Further, the pressing plate is provided with a recessed cavity and a circumferential retaining edge surrounding the recessed cavity. The outer surface of the bottom wall of the recessed cavity is fitted to a slightly deformable part, and two lateral sides are provided on the thin wall. The connecting post is arranged with two through holes in the circumferential retaining edge, the connecting post passes through the through hole to limit the up and down direction of the circumferential retaining edge and the left and right direction, and the compression band is a plastic part, and There are two, which are located on the upper and lower sides of the connecting column, respectively, so that the compression plate compacts the thin wall. The concave cavity provided can locally concentrate the pressing force of the pressing belt, which is beneficial to the local deformation of the side wall of the receiving cavity. The circumferential retaining edge is sleeved on the connecting post through the through hole, which can achieve preliminary positioning and avoid the installation of the pressing belt. Resulting in displacement.

Further, the accommodating cavity and the upper cover of the bracket are made of plastic to reduce the weight of the bracket. The upper cover is divided into two by a support plate, and two sides of the support plate are respectively provided with a series region composed of a series connection plate and A mixed connection area composed of a parallel connection plate and a series connection plate. The series connection area has at least two series connection plates arranged side by side. The mixed connection area is provided with series connection plates and parallel connection plates arranged alternately and side by side. The parallel connection plate is located at an end of the mixed connection area. The use of multiple cells ensures that the current and voltage of the battery meet the requirements, and the series and parallel regions make the cell layout more reasonable and compact.

Further, each of the series connection plate and the parallel connection plate is provided with a through slot for a limiting pole, one end of the series connection plate is plugged on the support plate, and the other end is riveted with the upper cover; the parallel connection plate One end is connected to the support plate by a plug and a connection part arranged in a gap, and the other end is riveted with the upper cover. This structure facilitates the rapid installation of the serial connection plate and the parallel connection plate on the upper cover. The gap-positioned inserts and connection portions make the parallel connection plate have better elasticity, and can avoid pulling the tabs during installation.

Further, the battery case includes a case body and a cover body for accommodating a bracket, a plurality of slots are provided in a lower portion of the accommodation cavity, and a plurality of insert plates are provided in the case body. The slot is plugged in, and the bracket and the shell body are fixedly connected by a sealant. The plug board and the slot cooperate with each other to make the initial connection between the shell body and the receiving cavity a detachable connection, which helps to adjust the position of each other, and then achieve a fixed connection through a sealant to prevent the receiving cavity from shaking in the shell body.

Further, a groove body surrounded by a plurality of rib plates is provided in the shell body, and the groove body is located at the connection between the shell body and the bracket. The groove body is used to receive the sealant, and the insert plates are arranged at intervals. On the slot body, there are also upper, lower and larger projections between each two insertion boards. The slots are arranged at intervals in the lower part of the bracket, and upper and lower projections are provided between each two slots. The bumps and the protruding pieces are against each other, so that the gap between the shell body and the bracket is arranged so that the sealant can be poured in and the bracket can dissipate heat.

Further, the cover body is provided with a connection port, and the connection port is covered with a rubber valve cap, which is elastic and has a dustproof and waterproof effect when not subject to external forces. When a gas is generated in the shell body and reaches a certain pressure It can be ejected by the gas at the time, and a vent cover with a vent hole is located on the upper part of the rubber valve cap for exhausting the gas.

The above-mentioned method for assembling a lithium-ion battery includes the following steps:

In step 1, a plurality of plate-shaped battery cells and two combined plates are placed in the receiving cavity, wherein the tabs of the battery cell are facing upward, and the plate-like surface is facing the thin wall having a slightly deformable part on the receiving cavity, and They are stacked one by one in the horizontal direction, and the combination board is placed between the thin wall and the battery core;

In step 2, two compression plates with recessed cavities are respectively sleeved on a support column located outside the accommodation cavity and are close to the thin wall. A self-enclosed compression belt is respectively arranged on the upper and lower sides of the support column. Cooperate tightly with the compression plate, so that the outer surface of the bottom wall of the cavity of the compression plate is in close contact with the slightly deformable part, and the slightly deformable part is changed from convex to concave, and then clings to the combination board, so that the combination board and the battery cell closely match ;

Step 3: Fix the upper cover on the upper part of the accommodating cavity, and the pole ears of the battery core are bent through the through grooves to be fixed on the upper cover to complete the assembly of the bracket;

Step 4: Put the assembled bracket into the shell body, so that a plurality of plug-in boards on the grooves in the shell body and a plurality of slots in the lower part of the receiving cavity are connected one by one, and The bumps and the protruding pieces located between the slots abut each other;

In step 5, a sealant is poured into the groove in the case body, so that the bracket is fixedly connected to the case body, and then the cover body is fixedly connected to the case body to complete the assembly of the lithium ion battery.

The compaction effect can be achieved only by compacting the compaction plate with the containing cavity through the compaction belt, which has the advantages of short assembly time and convenient assembly, and saves time and labor. In addition, when the battery is used at high temperature (such as 60 ° C) When the current density is easily distributed, it is easy to speed up the loss of cell capacity. This method uses a compression belt to press the compression plate and the thin wall to make the cells close to each other, which can reduce the uneven distribution of current density and cause rapid loss. The influence of battery capacity increases the storage life of lithium-ion batteries under high temperature conditions.

Further, the pressure applied by the pressing belt to the pressing plate per unit area is preferably 20 to 300 kPa. When the pressure of the pressure band is too large, it is easy to squeeze the battery core to deform and affect the storage life. If the pressure of the pressure band is insufficient, the proper compression effect cannot be achieved.

The invention has the beneficial effect that the lithium-ion battery uses a compression tape to press the thin walls of the receiving cavity inward, so that the stacked battery cells are compressed, so as to reduce the adverse effect caused by the battery cell bulging. It is beneficial to achieve rapid assembly and save production costs; the assembly method used is short in assembly time, convenient to assemble, and saves time and effort; in addition, in this method, a compression belt is used to compress the compression plate and the thin wall, so that the battery cell is closely attached. , Can reduce the impact of uneven current density distribution caused by rapid loss of cell capacity, and extend the storage life of lithium-ion batteries under high temperature conditions.

BRIEF DESCRIPTION OF THE DRAWINGS

1 is a schematic diagram of an assembly structure of a lithium ion battery;

FIG. 2 is a schematic diagram of a bracket assembly structure;

FIG. 3 is a structural schematic view of an upper cover;

4 is a schematic structural diagram of a shell body;

FIG. 5 is a structural diagram of a battery cell;

In the figure, 1-bracket; 11-accommodating cavity; 111-thin wall; 112-slightly deformable part; 113-connecting column; 114-slot; 115-projecting piece; 12-pressing plate; 121-concave cavity 122-peripheral flange; 123-through hole; 13-upper cover; 131-support plate; 132-series connection plate; 133-parallel connection plate; 1331-plug-in; 1332-connecting portion; 134-through slot; 2 -Battery core; 21-pole ears; 22-plate-like surface; 3-pressing tape; 4-shell body; 41-plug board; 42-slot body; 43-bump; 5-cover body; 51-connection Port; 52-rubber valve cap; 53-ventilation cover piece; A-series area; B-mixed area; 6-combination plate.

detailed description

The technical solutions of the embodiments of the present invention are explained and described below with reference to the accompanying drawings of the present invention, but the following embodiments are only preferred embodiments of the present invention, but not all of them. Based on the examples in the implementation mode, other embodiments obtained by those skilled in the art without creative work all belong to the protection scope of the present invention.

As shown in FIG. 1 to FIG. 5, the lithium-ion battery of this embodiment includes a bracket 1 for assembling a battery cell 2 and a battery case for containing the bracket 1. The bracket 1 includes a battery cell 2 for containing the battery cell 2. The accommodating cavity 11 and the upper cover 13 fixed on the upper part of the accommodating cavity 11. A plurality of plate-shaped battery cells 2 are vertically placed in the accommodating cavity 11 and stacked laterally one after the other. 21 is fixed on the upper cover 13, the side wall of the accommodating cavity 11 is pressed by two closed compression tapes 3, so that the direction in which the side wall of the accommodating cavity 11 is pressed against the battery core 2 overlaps with the battery core 2. The direction is the same.

The accommodating cavity 11 is a box-shaped cavity with a closed bottom. The side wall includes two thin walls 111 oppositely arranged and having a slightly deformable portion 112. A combination plate 6 is provided between the thin wall 111 and the battery cell 2. The combination plate 6 is composed of a plastic plate that is in close contact with the battery core 2 and a metal plate that is in close contact with the thin wall 111. A compression plate 12 is provided between the compression belt 3 and the thin wall 111. The compression plate 12 is pressed by the pressing belt 3, so that the slightly deformable part 112 of the thin wall 111 changes from convex to concave and then abuts on the combination plate 6 to compact the battery core 2. The slightly deformable portion 112 is a convex structure before the battery cell 2 is assembled, and an installation space is reserved for the battery cell 2 to prevent mutual interference between the battery cells 2. After the battery cell 2 is assembled, the slightly deformable portion 112 is pressed. After the clamping plate 12 is compressed, it changes from convex to concave to cause local stress. The combination plate 6 is used to protect the battery core 2, the metal plate prevents the battery core 2 from being crushed, and the plastic plate is insulated from the battery core 2.

The pressing plate 12 is provided with a recessed cavity 121 and a circumferential retaining edge 122 surrounding the recessed cavity 121. The outer surface of the bottom wall of the recessed cavity 121 fits the slightly deformable portion 112, and the thin wall 111 is provided on the outside. There are two laterally arranged connecting pillars 113, and two through holes 123 are opened in the circumferential blocking edge 122, and the connecting pillars 113 pass through the through holes 123 to limit the vertical and horizontal directions of the circumferential blocking edge 122. The pressing belt 3 is a plastic piece and is provided with two, which are respectively located on the upper and lower sides of the connecting post 113, so that the pressing plate 12 presses the thin wall 111. The provided cavity 121 can locally concentrate the pressing force of the compression band 3, which is beneficial to the local deformation of the side wall of the receiving cavity 11, and the circumferential retaining edge 122 is sleeved on the connecting post 113 through the through hole 123, which can achieve preliminary positioning. Avoid displacement when installing the pressure band 3.

The accommodating cavity 11 and the upper cover 13 of the bracket 1 are plastic parts to reduce the weight of the bracket 1. The upper cover 13 is divided into two by a support plate 131, and serial connection plates 132 are provided on both sides of the support plate 131. The series connection area A and the parallel connection area B composed of the parallel connection plate 133 and the series connection plate 132 have at least two serial connection plates 132 arranged side by side in the series connection area A, and the mixed connection area B is provided with alternation. The series connection plate 132 and the parallel connection plate 133 are arranged side by side, and the parallel connection plate 133 is located at the end of the mixed connection area B. The use of multiple cells 2 ensures that the current and voltage of the battery meet the requirements, and the series region A and the parallel region make the layout of the cells 2 more reasonable and more compact.

Each of the series connection plate 132 and the parallel connection plate 133 is provided with a through groove 134 for limiting the pole tab 21. One end of the series connection plate 132 is plugged on the support plate 131, and the other end is riveted with the upper cover 13. One end of the parallel connection plate 133 is connected to the support plate 131 through a gap-inserted plug-in 1331 and a connection portion 1332, and the other end is riveted with the upper cover 13. This structure facilitates the rapid installation of the serial connection plate 132 and the parallel connection plate 133 on the upper cover 13. The gap-inserted plug-in 1331 and the connection portion 1332 make the parallel connection plate 133 have good elasticity, and can avoid pulling the tabs 21 during installation. .

The battery case includes a case body 4 and a cover body 5 for accommodating the bracket 1. A plurality of slots 114 are provided in a lower portion of the accommodation cavity 11, and a plurality of insert plates 41 are provided in the case body 4. The plug-in board 41 is inserted into the slot 114, and the bracket 1 and the shell body 4 are fixedly connected by a sealant. The plug board 41 and the slot 114 cooperate with each other to make the preliminary connection of the shell body 4 and the receiving cavity 11 a detachable connection, which helps to adjust the position of each other, and then achieve a fixed connection through a sealant to avoid the receiving cavity 11 in the shell body 4 Shaking occurs.

The shell body 4 is provided with a groove body 42 surrounded by a plurality of rib plates. The groove body 42 is located at the connection between the shell body 4 and the bracket 1. The groove body 42 is used to receive the sealant. 41 are arranged on the slot body 42 at intervals, and upper and lower big projections 43 are provided between each two plug-in plates 41. The slots 114 are arranged at a lower portion of the bracket 1 and are provided between each two slots 114. There are large, small and small protruding pieces 115, and the protruding pieces 43 abut against the protruding pieces 115, so that the shell body 4 and the bracket 1 are arranged in a gap, so that the sealant can be poured in and the bracket 1 can dissipate heat.

The cover 5 is provided with a connection port 51. The connection port 51 is covered with a rubber valve cap 52, which is elastic and has the function of preventing dust and water when it is not subjected to external forces. When gas is generated in the shell body 4 and reaches It can be ejected by the gas at a certain pressure. A vent cover 53 with a vent hole is located on the upper part of the rubber valve cap 52 for exhausting the gas.

In step 1, a plurality of plate-shaped battery cells 2 and two combined plates 6 are placed in the receiving cavity 11, wherein the tabs 21 of the battery cells 2 face upward and the plate-shaped surface 22 faces the receiving cavity 11. The thin wall 111 of the deformed part 112 is sequentially stacked in the horizontal direction, and the combination board 6 is placed between the thin wall 111 and the battery core 2;

In step 2, two compression plates 12 with a cavity 121 are respectively sleeved on a support column located outside the accommodation cavity 11 and are close to the thin wall 111. A self-closing compression belt is respectively provided on the upper and lower sides of the support column. 3. The compression band 3 is tightly matched with the compression plate 12 so that the outer surface of the bottom wall of the cavity 121 of the compression plate 12 is in close contact with the slightly deformable portion 112, and the slightly deformable portion 112 is changed from convex to concave and fits tightly Combining board 6 so that the combining board 6 and the battery core 2 are closely matched;

In step 3, the upper cover 13 is fixed on the upper part of the accommodating cavity 11, the tab 21 of the battery core 2 passes through the through groove 134 and is bent to be fixed on the upper cover 13 to complete the assembly of the bracket 1.

Step 4: Put the assembled bracket 1 into the shell body 4, so that a plurality of the insert plates 41 on the grooves 42 in the shell body 4 and a plurality of slots 114 on the lower part of the receiving cavity 11 are connected one by one. And the projection 43 between the inserting plates 41 and the projection 115 between the insertion slots 114 abut each other;

In step 5, a sealant is poured into the groove body 42 in the case body 4 so that the bracket 1 and the case body 4 are fixedly connected, and then the cover body 5 and the case body 4 are fixedly connected to complete the assembly of the lithium ion battery.

The pressing belt 3 has a width of 19 mm and a length of 730 mm, and the pressing pressure applied by the pressing belt 33 to the pressing plate 12 is 1000 N. When the pressure of the pressure band is too large, it is easy to squeeze and deform the battery core 22 and affect the storage life. If the pressure of the pressure band is insufficient, the proper compression effect cannot be obtained.

Example 2

This embodiment differs from Embodiment 1 in that the pressure applied by the pressure belt 3 to the pressure plate 12 is 2000N.

Comparative example

In this embodiment, no pressing force is applied to the lithium ion battery.

The comparison result of the capacity retention rate is shown in Table 1. When the capacity of the lithium-ion battery is less than 60%, it cannot be used. It can be seen from the table that the storage life of the lithium-ion battery in the comparative example is 1 month when no pressing force is applied. Examples 1 and The storage life of the lithium-ion battery in Example 2 was improved. The storage life of the lithium-ion battery in Example 1 was extended to 3 months, and the storage life of the lithium-ion battery in Example 2 was extended to more than 3 months. Therefore, it can be known that the assembly method of the present invention can extend the storage life of the lithium ion battery at 60 ° C.

Table 1 shows the capacity retention rates of the lithium ion batteries in the examples and comparative examples at 60 ° C.

时间time	对比例Comparative example	实施例1Example 1	实施例2Example 2
1个月1 month	60％60%	76％76%	90％90%
2个月2 months	--	67％67%	85％85%
3个月3 months	--	60％60%	80％80%

The above are only specific embodiments of the present invention, but the scope of protection of the present invention is not limited to this. Those skilled in the art should understand that the present invention includes but is not limited to the content described in the drawings and the specific embodiments above. . Any modification that does not depart from the functional and structural principles of the present invention will be included in the scope of the claims.

Claims

A lithium-ion battery includes a bracket for assembling a battery cell and a battery case for containing the bracket. The bracket includes a receiving cavity for receiving a battery cell and an upper cover fixed on an upper portion of the receiving cavity. A plurality of plate-shaped battery cells are placed vertically in the receiving cavity and stacked laterally one after the other, and the tab at the upper end of each battery cell is fixed on the upper cover, and the side wall of the receiving cavity is closed by at least one The compression band of the cell is pressed so that the direction in which the side wall of the accommodating cavity presses the battery cells is the same as the direction in which the battery cells are stacked.
The lithium-ion battery according to claim 1, wherein the receiving cavity is a box-shaped cavity with a closed bottom, and a sidewall of the receiving cavity includes two thin walls which are oppositely arranged and have a slightly deformable part, and the thin wall and the electric A combination plate is provided between the cores, and the combination plate is composed of a plastic plate that is in close contact with the battery core and a metal plate that is in close contact with the thin wall, and a compression plate is provided between the compression belt and the thin wall. The compression plate is compressed by the compression band, so that the slightly deformable part of the thin wall is changed from convex to concave, and then clings to the combination plate to compact the battery core.
The lithium ion battery according to claim 2, characterized in that the pressing plate is provided with a concave cavity and a circumferential retaining edge surrounding the cavity, and the outer surface of the bottom wall of the concave cavity can be abutted. Slightly deformed part, two laterally arranged connecting posts are provided on the outer side of the thin wall, and two through holes are formed in the circumferential retaining edge, and the connecting posts pass through the through holes to limit the upward and downward directions of the circumferential retaining edge. Position, the compression band is a plastic piece, and two are provided, which are respectively located on the upper and lower sides of the connecting column, so that the compression plate compacts the thin wall.
The lithium-ion battery according to claim 1, wherein the receiving cavity and the upper cover of the bracket are plastic parts, the upper cover is divided into two by a support plate, and two sides of the support plate are respectively provided in series A series area composed of connecting plates and a parallel connection area composed of parallel connection plates and series connection plates. There are at least two series connection plates arranged side by side in the series area. Alternating and side by side series connection is provided in the mixed area. A connection board and a parallel connection board, the parallel connection board is located at an end of the mixed connection area.
The lithium-ion battery according to claim 4, characterized in that each of the series connection plate and the parallel connection plate is provided with a through slot for limiting a pole, and one end of the series connection plate is plugged into a support plate, The other end is riveted to the upper cover; one end of the parallel connection plate is connected to the support plate through an insert and a connection part arranged in a gap, and the other end is riveted to the upper cover.
The lithium-ion battery according to claim 1, wherein the battery case includes a case body and a cover body for accommodating a bracket, a plurality of slots are provided in a lower portion of the accommodation cavity, and the case body is provided inside There are multiple plug-in boards, the plug-in boards are plugged into the slots, and the bracket and the shell body are fixedly connected by a sealant.
The lithium-ion battery according to claim 6, wherein a groove body surrounded by a plurality of ribs is provided in the shell body, the groove body is located at the connection between the shell body and the bracket, and the groove body is used for To accommodate the sealant, the insert boards are arranged on the slot at intervals, and small bumps are provided between each two insert boards. The slots are arranged at the lower part of the bracket. There are upper and lower small protruding pieces, and the protruding pieces abut against the protruding pieces, so that the shell body and the bracket are arranged in a gap.
The lithium ion battery according to claim 6, wherein the cover is provided with a connection port, the connection port is covered with a rubber bonnet, and a ventilation cover sheet with a vent hole is located on the upper part of the rubber bonnet For exhausting gas.
The method for assembling a lithium ion battery according to any one of claims 1 to 8, further comprising the following steps:

In step 1, a plurality of plate-shaped battery cells and two combined plates are placed in the receiving cavity, wherein the tabs of the battery cell are facing upward, and the plate-like surface is facing the thin wall having a slightly deformable part on the receiving cavity, and They are stacked one by one in the horizontal direction, and the combination board is placed between the thin wall and the battery core;

In step 2, two compression plates with recessed cavities are respectively sleeved on a support column located outside the accommodation cavity and are close to the thin wall. A self-enclosed compression belt is respectively arranged on the upper and lower sides of the support column. Cooperate tightly with the compression plate, so that the outer surface of the bottom wall of the cavity of the compression plate is in close contact with the slightly deformable part. ;

Step 3: Fix the upper cover on the upper part of the accommodating cavity, and the pole ears of the battery core are bent through the through grooves to be fixed on the upper cover to complete the assembly of the bracket;

Step 4: Put the assembled bracket into the shell body, so that a plurality of plug-in boards on the grooves in the shell body and a plurality of slots in the lower part of the receiving cavity are connected one by one, and The bumps and the protruding pieces located between the slots abut each other;

In step 5, a sealant is poured into the groove in the case body, so that the bracket is fixedly connected to the case body, and then the cover body is fixedly connected to the case body to complete the assembly of the lithium ion battery.
The method for assembling a lithium ion battery according to claim 9, wherein the pressure applied by the pressing belt to the pressing plate per unit area is 20 to 300 kPa.