Battery busbar structure integration method and battery pack

Abstract

The application relates to the technical field of lithium ion batteries, and proposes a battery busbar structure integration method and a battery pack, which comprises the following steps: S1, integrating an elastic busbar on a box cover; S2, leading out the pole lug of a battery to the outside and corresponding the pole lug to the elastic busbar; S3, arranging a plastic plate between the box cover and the battery, opening a positioning groove on one side of the plastic plate facing the box cover, and opening a through hole in the positioning groove; S4, passing the pole lug through the through hole and folding and embedding the positioning groove; S5, folding the box cover and the plastic plate, and fixing the local plastic plate by heat melting, so that the elastic busbar is pressed against the pole lug. The integrated structure avoids the exposure of the elastic busbar, so the insulation protection effect is good, the convenience of integration is improved, meanwhile, the heat melting connection structure makes the box cover and the plastic plate easy to separate, the rework maintenance is facilitated, the group mode without welding points also reduces the production cost.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lithium ion batteries, in particular to a battery busbar structure integration method and a battery pack. BACKGROUND

[0002] The lithium ion battery pack is an important part of the power supply system in an electric vehicle, which is composed of a plurality of battery monomers and connected through busbars to form a plurality of battery modules, and then the whole is placed in a box, and cooperates with components such as a battery management system (BMS) to form a complete battery pack structure.

[0003] The utility model with the authorized publication number CN210744059U discloses a tab and busbar connecting structure and battery module, and the tab and busbar connecting structure comprises a first busbar, a second busbar and a plurality of tabs, a plurality of parallel slits are formed in the first busbar, the first busbar comprises a first side surface attached to the second busbar and a second side surface away from the second busbar, one end of the tab is bent after passing through the slit and is attached to the first side surface, the second busbar is welded with the first busbar, and the second busbar presses the part of the tab attached to the first busbar.

[0004] In the above technical solution, the tab is directly connected with the busbar, and when the tab and the busbar are fixed, the first busbar and the second busbar are welded to clamp the tab.

[0005] This integrated structure has the following disadvantages: first, the busbar needs to be connected with the tabs of a plurality of batteries, so the exposed area of the busbar is large, and it is difficult to set corresponding insulation measures; second, in order to ensure the connection strength and the stable clamping of the tab, there are many welding points between the first busbar and the second busbar, and a plurality of welding machines are needed for welding, which increases the cost, and it is not convenient for rework and maintenance. SUMMARY

[0006] Therefore, the present application provides a battery busbar structure integration method and a battery pack with good insulation performance and convenient rework and maintenance, to solve the problems of the existing busbar and battery integration structure, such as difficulty in setting insulation protection measures, high cost and inconvenience for rework and maintenance.

[0007] The technical solution of the present application is as follows:

[0008] On the one hand, the present application provides a battery busbar structure integration method, comprising the following steps:

[0009] S1, integrating an elastic busbar on a box cover;

[0010] S2, leading out the tab of the battery to the outside and corresponding to the elastic busbar;

[0011] S3, a plastic plate is arranged between the box cover and the battery, and a positioning groove is formed on the side of the plastic plate facing the box cover, and a through hole is formed in the positioning groove;

[0012] S4, the tab is inserted through the through hole, and the tab is inserted into the positioning groove;

[0013] S5, the box cover and the plastic plate are folded together, and the local plastic plate is fixed by heat melting, so that the elastic bus bar is pressed against the tab.

[0014] On the basis of the above technical scheme, preferably, step S5 comprises:

[0015] S51, a positioning hole is formed in the box cover;

[0016] S52, a heat melting nail is integrated on the plastic plate;

[0017] S53, the box cover and the plastic plate are folded together, and the heat melting nail is inserted through the positioning hole, and then the heat melting nail is fixed by heat melting.

[0018] On the basis of the above technical scheme, preferably, step S5 is performed, a limiting block is arranged between the box cover and the plastic plate, and after the box cover and the plastic plate are fixed by heat melting of the heat melting nail, the limiting block is removed, so that a gap is formed between the box cover and the plastic plate.

[0019] On the other hand, the application provides a battery pack made by using the above battery bus structure integration method.

[0020] On the basis of the above technical scheme, preferably, comprising a box cover, an elastic bus bar, a battery, a tab and a plastic plate, wherein,

[0021] The box cover is a sealing box cover of the battery pack;

[0022] The elastic bus bar is arranged on the inner side of the box cover;

[0023] The battery is arranged in the battery pack;

[0024] The tab is electrically connected with the bare cell inside the battery and extends to the outside;

[0025] The plastic plate is arranged between the battery and the box cover, the tab is inserted through the plastic plate, and the tab is electrically connected with the elastic bus bar.

[0026] On the basis of the above technical scheme, preferably, the elastic bus bar comprises a bus bar sheet and an elastic body, wherein the bus bar sheet is arranged opposite to the box cover; the elastic body is arranged between the bus bar sheet and the box cover, and the elastic body is fixedly connected with the bus bar sheet and the box cover.

[0027] On the basis of the above technical scheme, preferably, a positioning groove is formed on the plastic plate, and at least two through holes are formed in the positioning groove.

[0028] The plurality of batteries are arranged in parallel, and two through holes in the positioning groove accommodate a tab on each battery.

[0029] On the basis of the above technical scheme, preferably, the tab comprises a connecting portion and a limiting portion, wherein,

[0030] One end of the connecting portion is electrically connected to a bare cell inside the battery, and the other end passes through the through hole;

[0031] The limiting portion is arranged on the end of the connecting portion away from the battery and is folded to both sides;

[0032] The thickness of the limiting portion is less than the depth of the positioning groove;

[0033] The busbar is embedded in the positioning groove.

[0034] On the basis of the above technical scheme, preferably, the thickness of the limiting portion and the elastic busbar is greater than the depth of the positioning groove, so that a gap is formed between the box cover and the plastic plate, and the thickness of the limiting portion and the busbar is less than the depth of the positioning groove.

[0035] On the basis of the above technical scheme, preferably, the edges of the box cover and the plastic plate are provided with an inclined chamfer.

[0036] The battery busbar integration method and the battery pack of the present application have the following advantages over the prior art:

[0037] (1) By passing the tab through the plastic plate and into the positioning groove, and integrating the elastic busbar on the box cover, the elastic busbar can be pressed against the tab to achieve electrical connection after the box cover and the plastic plate are fixed by heat melting. This structure avoids the exposure of the elastic busbar, so the insulation protection effect is good. Not only does it improve the convenience of integration, but also the heat melting connection structure makes it easy to separate the box cover and the plastic plate, facilitating rework and repair. The group mode without solder points also reduces production costs.

[0038] (2) The box cover is provided with a positioning hole, and the plastic plate is provided with a hot melt pin. In this way, during integration, the hot melt pin can be inserted into the positioning hole of the box cover to achieve positioning, so that the elastic busbar can be easily pressed against the tab to improve assembly accuracy. At the same time, by heat melting the hot melt pin, it is convenient to fix and will not damage the structure of the box cover and the plastic plate.

[0039] (3) The elastic busbar is composed of a busbar and an elastic body. In this way, the elastic body can tightly press the tab against the busbar, thereby ensuring the stability of the overcurrent performance and the structure.

[0040] (4) The tab has two parts: a connecting part and a limiting part. The limiting part is placed in the positioning groove of the plastic plate and contacts the busbar of the elastic busbar. By controlling the sum of the thickness of the limiting part and the elastic busbar to be greater than the depth of the positioning groove, a gap is formed between the box cover and the plastic plate, which can be used for air circulation to achieve cooling work, thereby ensuring normal power of the battery;

[0041] (5) By setting chamfers on the edges of the box cover and the plastic plate, it is convenient to insert a tool to separate the hot-melt connection part between the box cover and the plastic plate, thereby improving the convenience of rework and maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0043] Figure 1 A diagram illustrating the separation structure of the battery pack cover and the plastic plate of the present invention;

[0044] Figure 2 A three-dimensional diagram of the connection structure between the tab and the plastic plate of the battery pack of the present invention;

[0045] Figure 3 A diagram showing the connection structure between the battery pack cover and the elastic busbar of the present invention;

[0046] Figure 4 This is a front view of the battery pack of the present invention;

[0047] Figure 5 For the present invention Figure 4 Middle AA section;

[0048] Figure 6 For the present invention Figure 5 A magnified view of the structure at point A;

[0049] In the figure: 1. box cover; 101. positioning hole; 2. elastic bus; 21. busbar; 22. elastomer; 3. battery; 4. tab; 41. connection part; 42. limit part; 5. plastic plate; 51. hot melt pin; 100. gap; 501. positioning groove; 502. through hole. DETAILED DESCRIPTION

[0050] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0051] As shown in the drawings, Figures 1-6 The battery pack of the present application comprises a box cover 1, an elastic busbar 2, a battery 3, a tab 4 and a plastic plate 5.

[0052] As shown in the drawings, Figures 1-6 The box cover 1 is a sealed box cover of the battery pack; the elastic busbar 2 is arranged on the inner side of the box cover 1; the battery 3 is arranged in the battery pack; the tab 4 is electrically connected with the bare cell inside the battery 3 and extends to the outer side; the plastic plate 5 is arranged between the battery 3 and the box cover 1, the tab 4 passes through the plastic plate 5 and is electrically connected with the elastic busbar 2;

[0053] In the above structure, the battery 3 adopts a structure without a pole, which directly extends the tab to the outer side of the battery 3 to realize electrical connection, which simplifies the battery structure, improves the convenience of grouping and reduces the application cost.

[0054] The plastic plate 5 is arranged for integrating the tab 4, the tab 4 is connected with the elastic busbar 2 integrated on the box cover 1 after passing through the plastic plate 5, so that most of the tab 4 is located between the plastic plate 5 and the box body 1, which can prevent the elastic busbar 2 from being exposed, effectively improves the insulation performance, and the elastic busbar 2 is integrated with the box cover 1 of the battery pack, which improves the convenience of subsequent grouping and does not need additional fasteners to fix the elastic busbar 2, thereby reducing the production cost.

[0055] Specifically, the elastic busbar 2 is integrally formed with the box cover 1 by injection molding.

[0056] The plastic plate 5 is made of an insulating material.

[0057] The box cover 1 is provided with a positioning hole 101, and the plastic plate 5 is provided with a hot melt nail 51, so that the hot melt nail 51 is inserted into the positioning hole 101 of the box cover 1 for hot melt fixing during integration.

[0058] This structure facilitates the subsequent disassembly of the box cover 1 and the plastic plate 5, thereby improving the convenience of rework and maintenance.

[0059] Meanwhile, this structure does not need welding during integration, so it does not need an expensive welding machine, which reduces the production cost.

[0060] In some embodiments, the connection with the box cover 1 is achieved by locally melting the plastic plate 5.

[0061] As shown in Figure 3 and Figure 6 , the elastic busbar 2 comprises a busbar sheet 21 and an elastic body 22, wherein the busbar sheet 21 is arranged opposite to the box cover 1; the elastic body 22 is arranged between the busbar sheet 21 and the box cover 1, and the elastic body 22 is fixedly connected with the busbar sheet 21 and the box cover 1;

[0062] As shown in the above structure, in the structure of the elastic busbar 2, the busbar sheet 21 abuts against the tab 4, and after the box cover 1 is integrated with the plastic plate 5, the busbar sheet 21 can be tightly attached to the tab 4 by the elastic force of the elastic body 22, so as to ensure the current-carrying capacity and improve the application stability.

[0063] As shown in Figure 2 and Figure 6 , a positioning groove 501 is formed on the plastic plate 5, and at least two through holes 502 are formed in the positioning groove 501; a plurality of batteries 3 are arranged side by side, and the two through holes 502 in the positioning groove 501 accommodate the tabs 4 on one battery 3 each;

[0064] As shown in the above structure, the positioning groove 501 on the plastic plate 5 is used to accommodate a part of the tab 4, and the tab 4 can pass through the plastic plate 5 through the through hole 502; each positioning groove 501 inserts the tabs 4 of two batteries 3 through the two through holes 502, so that the series connection between the batteries 3 can be achieved by means of the elastic busbar 2.

[0065] As shown in Figure 6 , the tab 4 comprises a connecting portion 41 and a limiting portion 42, wherein one end of the connecting portion 41 is electrically connected with a bare cell inside the battery 3, and the other end passes through the through hole 502; the limiting portion 42 is arranged on the end of the connecting portion 41 away from the battery 3 and is folded to both sides; the thickness of the limiting portion 42 is less than the depth of the positioning groove 501; the busbar sheet 21 is embedded in the positioning groove 501;

[0066] As shown in the above structure, when the tab 4 is arranged, the end of the connecting portion 41 passes through the through hole 502 into the positioning groove 501 and is folded to both sides to form the limiting portion 42, so that when the box cover 1 is assembled, the elastic busbar 2 abuts against the limiting portion 42;

[0067] In this way, the abutting area of the tab 4 and the busbar sheet 21 can be increased by folding the limiting portion 42, so as to improve the structural strength of the assembly;

[0068] In this way, by controlling the thickness of the limiting portion 42 to be less than the thickness of the positioning groove 501, the busbar sheet 21 of the elastic busbar 2 can be embedded in the positioning groove 501, thereby improving the stability and insulation protection capability of the assembly;

[0069] Specifically, the box cover 1 can be supported on the plastic plate 5 .

[0070] like Figure 6 As shown, the sum of the thickness of the limiting portion 42 and the elastic busbar 2 is greater than the depth of the positioning groove 501, so that a gap 100 is formed between the box cover 1 and the plastic plate 5;

[0071] As in the above structure, by controlling the thickness of the limiting portion 42 and the elastic bus 2 and the depth greater than the positioning groove 501, a gap 100 is formed between the box cover 1 and the plastic plate 5, thereby achieving air circulation and improving the heat dissipation capacity, thereby avoiding the problem of heat accumulation between the box cover 1 and the plastic plate 5 and ensuring the normal power of the battery 3.

[0072] Furthermore, the sum of the thickness of the limiting portion 42 and the busbar 21 is smaller than the depth of the positioning groove 501 , so that the busbar 21 is entirely located in the positioning groove 501 to ensure structural stability.

[0073] In some embodiments, the box cover 1 and the plastic plate 5 are surrounded by a dustproof net;

[0074] Specifically, after the box cover 1 and the plastic plate 5 are integrated, a rectangular frame-shaped dustproof net is set and mounted around the box cover 1 and the plastic plate 5 to close the gap 100, thereby preventing foreign matter from entering and affecting the current transmission capability, thereby improving the safety of the application.

[0075] Furthermore, the edges of the box cover 1 and the plastic plate 5 are provided with bevel chamfers; this facilitates the insertion of a tool to separate the hot-melt connection portion of the box cover 1 and the plastic plate 5, thereby improving the convenience of rework and repair.

[0076] The battery bus structure integration method of the present invention comprises the following steps:

[0077] S1, integrating the elastic busbar 2 on the box cover 1;

[0078] S2. Lead the tab 4 of the battery 3 to the outside and align the tab 4 with the elastic bus 2;

[0079] S3. A plastic plate 5 is provided between the box cover 1 and the battery 3. A positioning groove 501 is provided on the side of the plastic plate 5 facing the box cover 1, and a through hole 502 is provided in the positioning groove 501.

[0080] S4, pass the tab 4 through the through hole 502, and fold it over to fit into the positioning groove 501;

[0081] S5 , closing the box cover 1 and the plastic plate 5 , and hot-melting the plastic plate 5 partially to fix them, so that the elastic busbar 2 presses the tab 4 tightly.

[0082] Step S5 includes:

[0083] S51, a positioning hole 101 is formed on the box cover 1;

[0084] S52, a hot-melt nail 51 is integrated on the plastic plate 5;

[0085] S53, the box cover 1 and the plastic plate 5 are brought together, and the hot-melt nail 51 passes through the positioning hole 101, and then hot-melt fixing is performed.

[0086] When the step S5 is executed, a limiting block is arranged between the box cover 1 and the plastic plate 5, and after the box cover 1 and the plastic plate 5 are hot-melt fixed by the hot-melt nail 51, the limiting block is taken out, so that a gap 100 is formed between the box cover 1 and the plastic plate 5;

[0087] When the step S5 is executed, a limiting block is arranged between the box cover 1 and the plastic plate 5, and after the box cover 1 and the plastic plate 5 are hot-melt fixed by the hot-melt nail 51, the limiting block is taken out, so that a gap 100 is formed between the box cover 1 and the plastic plate 5;

[0088] The above only describes the preferred embodiments of the present application and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A battery bus structure integration method, characterized in that: The following steps are involved: S1, integrating a flexible busbar (2) on the box cover (1); S2, leading the tab (4) of the battery (3) to the outside, and aligning the tab (4) with the elastic busbar (2); S3, arranging a plastic plate (5) between the box cover (1) and the battery (3), and providing a positioning groove (501) on a surface of the plastic plate (5) facing the box cover (1), and providing a through hole (502) in the positioning groove (501); S4, passing the tab (4) through the through hole (502), and folding it over to fit into the positioning groove (501); S5. The box cover (1) and the plastic plate (5) are closed together, and the plastic plate (5) is partially fixed by hot melting, so that the elastic busbar (2) is pressed against the tab (4).

2. The battery bus structure integration method according to claim 1, wherein: The step S5 comprises: S51, opening a positioning hole (101) in the box cover (1); S52, integrating hot-melt pins (51) on the plastic plate (5); S53, the box cover (1) and the plastic plate (5) are brought together, and the hot-melt nail (51) is passed through the positioning hole (101), and then fixed by hot-melt.

3. The battery bus structure integration method according to claim 2, characterized in that: When step S5 is executed, a limit block is set between the box cover (1) and the plastic plate (5). After the box cover (1) and the plastic plate (5) are fixed by hot-melt fixing using the hot-melt nails (51), the limit block is removed to form a gap (100) between the box cover (1) and the plastic plate (5).

4. A battery pack, characterized in that: The battery bus structure is manufactured using the battery bus structure integration method according to any one of claims 1 to 3.

5. The battery pack according to claim 4, wherein: It comprises a box cover (1), an elastic busbar (2), a battery (3), a tab (4) and a plastic plate (5), wherein: The box cover (1) is a sealed box cover of the battery pack; The elastic busbar (2) is arranged on the inner side of the box cover (1); The battery (3) is arranged in the battery pack; The tab (4) is electrically connected to the bare cell inside the battery (3) and extends to the outside; The plastic plate (5) is arranged between the battery (3) and the box cover (1); the tab (4) passes through the plastic plate (5) and is electrically connected to the elastic busbar (2).

6. The battery pack according to claim 5, wherein: The elastic busbar (2) comprises a busbar (21) and an elastic body (22), wherein: The busbar (21) is arranged opposite to the box cover (1); The elastic body (22) is arranged between the busbar (21) and the box cover (1), and the elastic body (22) is fixedly connected to the busbar (21) and the box cover (1).

7. The battery pack according to claim 6, wherein: The plastic plate (5) is provided with the positioning groove (501), and at least two through holes (502) are provided in the positioning groove (501); A plurality of batteries (3) are arranged in parallel, and the two through holes (502) in the positioning groove (501) each accommodate one of the tabs (4) on the battery (3).

8. The battery pack according to claim 6, wherein: The tab (4) comprises a connecting portion (41) and a limiting portion (42), wherein: One end of the connecting portion (41) is electrically connected to the bare cell inside the battery (3), and the other end passes through the through hole (502); The limiting portion (42) is arranged on an end of the connecting portion (41) away from the battery (3) and is folded toward both sides; The thickness of the limiting portion (42) is smaller than the depth of the positioning groove (501); The busbar (21) is embedded in the positioning groove (501).

9. The battery pack according to claim 8, wherein: The sum of the thicknesses of the limiting portion (42) and the elastic busbar (2) is greater than the depth of the positioning groove (501), so that a gap (100) is formed between the box cover (1) and the plastic plate (5), and the sum of the thicknesses of the limiting portion (42) and the busbar (21) is less than the depth of the positioning groove (501).

10. The battery pack according to any one of claims 5 to 8, wherein: The edges of the box cover (1) and the plastic plate (5) are provided with chamfers.

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