Lithium battery module

Abstract

A lithium battery module includes a lithium battery pack, two detachable holders, and a plurality of conductive patches. The two detachable holders are respectively installed on the positive and negative electrodes of the lithium battery pack, and each detachable holder includes a plurality of splicing monomers; the splicing monomer includes a splicing base and a plurality of docking buckles, the splicing base is provided with a receiving cavity and a welding through hole, the welding through hole is communicated with the receiving cavity, a plurality of docking buckles are all arranged on the outer wall of the splicing base, and each docking buckle includes a male buckle and a female buckle; the plurality of conductive patches are mutually attached. The detachable holder is formed by docking a plurality of splicing monomers, and the number of splicing monomers can be increased or decreased according to the number of battery monomers in the actually produced battery module without re-designing the holder, saving the design cost; each splicing monomer is mutually buckled with the adjacent splicing monomer through the docking buckle, which is convenient for disassembly and assembly; the plurality of splicing monomers are electrically connected through the conductive patches, reducing the welding parts and improving the assembly efficiency of the battery module.

Description

Technical Field

[0001] The present invention relates to a battery, and particularly to a lithium battery module. Background Art

[0002] A battery module can be understood as an intermediate product between a battery cell and a pack formed by combining lithium-ion battery cells in series and parallel and installing a monitoring and management device for individual battery cells. By connecting each lithium battery cell in series and parallel with each other, the output power of the battery module can reach the rated value of the electrical appliance. When the lithium battery cells are connected in parallel with each other, the output voltage of the combined battery pack remains unchanged, while the capacity and output current are increased; further, when each battery pack is connected in series, the current of the formed battery module remains unchanged, while the voltage increases, so that the output current and output voltage of the battery module meet the usage requirements of the electrical appliance. That is, in order to meet the usage requirements of the electrical appliance, there are series and parallel connection relationships in the same battery module.

[0003] In order to obtain the target output capacitance and output current, it is necessary to connect each battery cell in parallel to form multiple battery packs. In order to make the output voltage of the battery module reach the rated voltage of the electrical appliance, it is necessary to connect each battery pack in series.

[0004] The battery module includes a plurality of battery cells, a caddy for fixing the battery cells, and a conductive sheet for electrically connecting each battery cell. When assembling the battery module, it is necessary to first place each battery cell into the caddy, and then place the conductive sheet on the positive / negative electrode of the battery cell for spot welding, thereby electrically connecting each battery cell.

[0005] However, during the spot welding process, due to objective reasons, phenomena such as wrong welding and virtual welding may occur, and it is necessary to remove the conductive sheet from the battery cell. In this process, the battery cell is very likely to be damaged, and the time consumption is long. In addition, the number of batteries that the existing caddy can accommodate is fixed, that is, in order to manufacture battery modules with different powers, it is necessary to design corresponding battery caddies for fixing, and it is necessary to re-design the mold for injection molding, with high design costs and lack of flexibility.

[0006] Therefore, how to optimize the structure of the existing battery module, reduce the design cost, make the assembly of the battery module more flexible, and make the loading and unloading of the battery module more convenient is a problem that those skilled in the art need to solve. Summary of the Invention

[0007] An object of the present invention is to overcome the deficiencies in the prior art and provide a lithium battery module in which the caddy can be flexibly combined according to requirements, and each battery cell can be quickly disassembled.

[0008] The object of the present invention is achieved by the following technical solutions:

[0009] A lithium battery module includes: a lithium battery pack, two detachable cartridges, and a plurality of conductive patches;

[0010] The two detachable cartridges are respectively installed on the positive electrode and the negative electrode of the lithium battery pack, and each of the detachable cartridges includes a plurality of splicing monomers;

[0011] In one of the splicing monomers, the splicing monomer includes a splicing base and a plurality of docking buckles. The splicing base is provided with a receiving cavity and a welding through hole, and the welding through hole communicates with the receiving cavity. A plurality of the docking buckles are all arranged on the outer wall of the splicing base, and the plurality of docking buckles are distributed in a circumferential array centered on the axis of the welding through hole, and each of the docking buckles includes a male buckle and a female buckle;

[0012] A plurality of the conductive patches are correspondingly arranged in a plurality of the splicing bases, and the plurality of conductive patches are mutually attached.

[0013] In one embodiment, the splicing base is provided with a pre-embedded groove, the pre-embedded groove is located on the inner wall of the receiving cavity, and the pre-embedded groove communicates with the welding through hole, and the conductive patch is embedded in the pre-embedded groove.

[0014] In one embodiment, the conductive patch includes an intermediate guiding portion and linking portions located at both ends of the intermediate guiding portion. The intermediate guiding portion is located in the pre-embedded groove, and the linking portions are located on the outer wall of the splicing base.

[0015] In one embodiment, the linking portion is located between the male buckle and the female buckle.

[0016] In one embodiment, a bending area is provided on the linking portion.

[0017] In one embodiment, the pre-embedded groove includes a first installation area and a second installation area, and the first installation area and the second installation area are respectively used for accommodating one of the conductive patches.

[0018] In one embodiment, the depth of the first installation area is greater than the depth of the second installation area.

[0019] In one embodiment, the splicing base further includes a plurality of elastic abutting strips, and the plurality of elastic abutting strips are arranged at intervals in the receiving cavity.

[0020] In one embodiment, the plurality of elastic abutting strips are distributed in a circumferential array centered on the axis of the welding through hole.

[0021] In one embodiment, the number of the elastic abutting strips is 4.

[0022] Compared with the prior art, the present invention has at least the following advantages:

[0023] 1. The detachable cato is formed by docking multiple splicing monomers. The number of splicing monomers can be increased or decreased according to the number of battery monomers in the actually produced battery module, without the need to redesign the cato, saving design costs;

[0024] 2. Each splicing monomer is buckled to each other through a docking buckle, which is convenient for disassembly and assembly;

[0025] 3. Electrical connection is achieved between multiple splicing monomers through conductive patches, reducing the welding parts and improving the assembly efficiency of the battery module. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for use in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as a limitation of the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative efforts.

[0027] Figure 1 It is a schematic structural diagram of a lithium battery module in an embodiment of the present invention;

[0028] Figure 2 For Figure 1 The assembly schematic diagram of the shown lithium battery module;

[0029] Figure 3 It is a schematic diagram of the cooperation between a lithium battery monomer and a splicing monomer in an embodiment of the present invention;

[0030] Figure 4 It is a schematic structural diagram of a splicing monomer in an embodiment of the present invention;

[0031] Figure 5 It is a schematic structural diagram of a conductive patch in an embodiment of the present invention;

[0032] Figure 6 It is a schematic structural diagram of a battery monomer in an embodiment of the present invention;

[0033] Figure 7 For Figure 6 The explosion view of the shown battery monomer;

[0034] Figure 8 It is a schematic diagram of the stress state at the position of one of the explosion-proof grooves on the housing when the battery expands internally;

[0035] Figure 9 It is a schematic diagram of the stress state between two adjacent arc-shaped gaskets when the battery is under external pressure;

[0036] Figure 10 Schematic structural view of a pressure relief cover;

[0037] Figure 11 Exploded view of the pressure relief cover;

[0038] Figure 12 Schematic structural view of the pressure relief cover in its initial state;

[0039] Figure 13 Schematic structural view of the pressure relief cover in its pressure relief state. Detailed implementation manners

[0040] For the convenience of understanding the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided so that the disclosure of the present invention can be understood more thoroughly and comprehensively.

[0041] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for the purpose of illustration and do not represent the only embodiments.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0043] Please refer to Figure 1 , a lithium battery module 10 includes: a lithium battery pack 100, two separable holders 200 and a plurality of conductive patches 300. The two separable holders 200 are respectively arranged on the positive electrode and the negative electrode of the lithium battery pack 100, and the separable holder 200 can be split into a plurality of splicing monomers 20, that is, the combined number of the splicing monomers 20 can be adjusted according to the number of battery monomers on the lithium battery pack 100, without re-designing the holder style, saving the design cost, and also reducing the maintenance difficulty due to the ability to be split.

[0044] The lithium battery pack 100 includes a plurality of battery monomers 110.

[0045] Two detachable connectors 200 are respectively installed on the positive and negative electrodes of the lithium battery pack 100, and each detachable connector 200 includes a plurality of splicing monomers 20. In one of the splicing monomers 20, the splicing monomer 20 includes a splicing base 210 and a plurality of docking buttons 220. The splicing base 210 is provided with a receiving cavity 211 and a welding through hole 212, and the welding through hole 212 communicates with the receiving cavity 211. A plurality of docking buttons 220 are all arranged on the outer wall of the splicing base 210, and the plurality of docking buttons 220 are arranged in a circumferential array centered on the axis of the welding through hole 212. Each docking button 220 includes a male button 221 and a female button 222. When two adjacent splicing monomers 20 are spliced, the male button 221 on the outer wall of the splicing base 210 is used to engage with the female button 222 on the adjacent splicing base 210, and the female button 222 on the outer wall of the splicing button 210 is used to accommodate the male button 221 on the adjacent splicing base 210.

[0046] Each splicing base 210 correspondingly covers the positive / negative electrode of a lithium battery cell 110, so that the positive / negative electrode of the lithium battery cell 110 is located in the receiving cavity 211 and is arranged facing the welding through hole 212. A lithium battery cell 110 is provided on both the positive and negative electrodes of the same lithium battery cell 110. The lithium battery cells 110 are fixed together by splicing between the lithium battery cells 110.

[0047] A plurality of conductive patches 300 are correspondingly arranged in a plurality of splicing bases 210, and the plurality of conductive patches 300 are mutually attached. After the positive / negative electrode of the lithium battery cell 110 enters the receiving cavity 211, it is attached to the conductive patch 300. After the adjacent splicing bases 210 are combined together, the two conductive patches 300 installed on the adjacent two splicing bases 210 are mutually attached. Thus, the adjacent two lithium battery cells 110 are electrically connected through the conductive patches 300. That is, after the battery cell 110 is installed in the detachable connector 200, the electrical connection with other battery cells 110 has been completed, reducing the working steps required for assembling the lithium battery module 10 and improving the production efficiency of the lithium battery module 10.

[0048] The assembly steps of the above lithium battery module 10 are introduced below:

[0049] Before assembly, it is necessary to confirm information such as the output power, output current, and output voltage of the lithium battery module 10 to confirm the specifications of the lithium battery cells 110, and determine how many lithium battery cells 110 need to be connected in parallel to form a lithium battery module, and how many lithium battery modules need to be connected in series;

[0050] First, load a plurality of conductive patches 300 into a plurality of splicing bases 210 one by one;

[0051] Next, splice multiple splicing bases 210. The male buckle 221 on the outer wall of the splicing base 210 is aligned with the female buckle 222 on the adjacent splicing base 210, and the female buckle 222 on the outer wall of the splicing base 210 faces the male buckle 221 on the adjacent splicing base 210. Apply force along the extension direction of the male buckle 221 to make the two splicing bases 210 snap together. Repeat the above operation to splice each splicing base 210 together in sequence. At this time, the conductive patches 300 on the spliced splicing bases 210 are connected to each other, and thus a detachable battery holder 200 is assembled;

[0052] After both detachable battery holders 200 are assembled, stack multiple battery cells 110 one by one into the receiving cavities 211 of multiple splicing bases 210, and cover another detachable battery holder 200 on the battery pack 100. At this time, the positive and negative electrodes of each battery cell 110 are connected together through the circuit formed by the conductive patches 300, that is, the internal circuit of the lithium battery module is connected at this time;

[0053] Then, detect the assembled lithium battery module 10;

[0054] After the detection is completed, weld the conductive patch 300 to the positive / negative electrode of the battery cell 110 through the welding through hole 212 to fix the lithium battery module 10.

[0055] It should be noted that if it is found during the detection process that the battery cell 110 is damaged or installed in the wrong direction, tools such as tweezers can be used to pull out the splicing base 210 covering the battery cell 110. After replacing the normal battery cell 110, the splicing base 210 can be loaded into the detachable battery holder 200 again through the docking buckle 220 for welding.

[0056] During subsequent maintenance, force can also be applied to the splicing base 210 of the problematic battery cell 110 alone to separate it from the battery cell 110, take out the welded battery cell 110 and conductive patch 300 together for replacement, and then reinstall the splicing base 210 back into the detachable battery holder 200.

[0057] In one embodiment, in order to facilitate the setting of the conductive patch 300, the splicing base 210 is provided with a pre-buried groove 213. The pre-buried groove 213 is located on the inner wall of the receiving cavity 211 and is communicated with the welding through hole 212. The conductive patch 300 is embedded in the pre-buried groove 213.

[0058] In one of the embodiments, the conductive patch 300 includes an intermediate guiding portion 310 and connecting portions 320 located at both ends of the intermediate guiding portion. The intermediate guiding portion 310 is located in the pre-buried groove 213, and the connecting portions 320 are located on the outer wall of the splicing base 210. The connecting portions 320 are located between the male buckle 221 and the female buckle 222.

[0059] In order to improve the connection tightness between two adjacent conductive patches 300 in the detachable caddy 200 and avoid poor contact, a bending area 321 is provided on the connection part 320.

[0060] It should be noted that according to the series / parallel requirements of each battery cell 10 in the lithium battery module 10, the installation quantity of the conductive patches 300 can be increased. In one embodiment, the embedded groove 213 includes a first installation area 213a and a second installation area 213b. The first installation area 213a and the second installation area 213b are respectively used to accommodate one conductive patch 300, and the depth of the first installation area 213a is greater than that of the second installation area 213b.

[0061] In order to improve the structural stability of the lithium battery module 10, the splicing base 210 further includes a plurality of elastic abutting strips 214, and the plurality of elastic abutting strips 214 are arranged at intervals in the receiving cavity 211. The plurality of elastic abutting strips 214 are arranged in a circumferential array centered on the axis of the welding through hole 212. In one embodiment, 4 elastic abutting strips 214 are provided.

[0062] Compared with the prior art, the present invention has at least the following advantages:

[0063] 1. The detachable caddy 200 is formed by docking a plurality of splicing monomers 20, and the number of splicing monomers 20 can be increased or decreased according to the number of battery cells in the actually produced battery module, without re-designing the caddy, saving the design cost;

[0064] 2. Each splicing monomer 20 is buckled with each other through the docking buckle 220, which is convenient for disassembly and assembly;

[0065] 3. The plurality of splicing monomers 20 are electrically connected through the conductive patches 300, reducing the welding parts and improving the assembly efficiency of the battery module.

[0066] It can be understood that during the use of the lithium battery, due to defects generated during the battery manufacturing process or abnormal use by the user, the heat generation inside the lithium battery cell 110 will increase abnormally, which will further cause the electrolyte to vaporize, prompting the internal pressure of the battery cell 110 to increase. When the battery cell 110 cannot withstand the pressure, an explosion will occur. In order to improve the safety performance of the lithium battery module 10 and avoid safety accidents caused by the explosion of the lithium battery cell 110.

[0067] The lithium battery cell 110 includes: a battery core 400, a housing 500, and a cover 600.

[0068] The housing 500 includes a housing body 510 and a plurality of arc-shaped gaskets 520. The housing body 510 is a cylindrical structure with openings at both ends. The housing body 510 is provided with a partition portion 511, a sealing cavity 512, and a main receiving cavity 513. The main receiving cavity 513 is used to accommodate the battery cell 400. The partition portion 511 is located on the inner wall of the housing body 510. The sealing cavity 512 and the main receiving cavity 513 are respectively located on both sides of the partition portion 511, and the sealing cavity 512 communicates with the main receiving cavity 513. A plurality of the arc-shaped gaskets 520 are all arranged in the main receiving cavity 513. The edges of every two adjacent arc-shaped gaskets 520 are in contact with each other, and a gap is provided between every two adjacent arc-shaped gaskets 520. A plurality of explosion-proof grooves 514 are formed on the outer wall of the housing body 510, and the plurality of explosion-proof grooves 514 are arranged corresponding to the plurality of gaps one by one;

[0069] The cover 600 includes a sealing ring 610, a pressure relief cover 620, and a bottom cover 630. The pressure relief cover 620 and the bottom cover 630 are respectively arranged at both ends of the housing body 510, and the pressure relief cover 620 is embedded in the sealing cavity 512 and abuts against the positive electrode of the battery cell 400. The sealing ring 610 is arranged in the sealing cavity 512 and is located between the pressure relief cover 620 and the sealing cavity 512.

[0070] To better illustrate the explosion-proof method of the above lithium battery cell 110 and better understand the concept of the above lithium battery cell 110. Please refer to Figure 6 and Figure 7 , the lithium battery cell 110 includes: a battery cell 400, a housing 500, and a cover 600. The battery cell 400 is accommodated in the housing 500, and the cover 600 is used to close the housing 500. By weakening the anti-expansion ability of the housing, the housing 500 cracks and relieves pressure before the internal pressure of the battery rises to the critical value of explosion, thereby improving the safety performance of the lithium battery cell 110.

[0071] Please refer to Figure 6 and Figure 7, the outer shell 500 includes a housing 510 and a plurality of arc-shaped gaskets 520. The housing 510 is a cylindrical structure with openings at both ends. The housing 510 is provided with a partition portion 511, a sealing cavity 512, and a main receiving cavity 513. The main receiving cavity 513 is used to accommodate the battery cell 400. The partition portion 511 is located on the inner wall of the housing 510. The sealing cavity 512 and the main receiving cavity 513 are respectively located on both sides of the partition portion 511, and the sealing cavity 512 communicates with the main receiving cavity 513. A plurality of arc-shaped gaskets 520 are all arranged in the main receiving cavity 513. The edges of every two adjacent arc-shaped gaskets 520 are in contact with each other, that is, the arc-shaped gaskets 520 are connected end to end. The arc-shaped gaskets 520 connected end to end form an annular support sleeve on the inner wall of the housing 510 to assist the housing 510 in resisting pressure. In one embodiment, six arc-shaped gaskets 520 are provided.

[0072] Please refer to Figure 8 , a gap is provided between every two adjacent arc-shaped gaskets 520. A plurality of explosion-proof grooves 514 are opened on the outer wall of the housing 510, and the plurality of explosion-proof grooves 514 are correspondingly arranged facing the plurality of gaps one by one. By opening the explosion-proof grooves 514, the thickness of the housing 510 is reduced, and thus the structural strength of the housing 510 is reduced. The position where the explosion-proof grooves 514 are located is the weak point of the housing 510. When a large amount of gas is generated due to a failure of the battery cell 110, causing the internal pressure of the housing 510 to rise, the housing 510 will crack along the position where the explosion-proof grooves 514 are located to release pressure.

[0073] Please refer to Figure 6 and Figure 7 , the cover 600 includes a sealing ring 610, a pressure relief cover 620, and a bottom cover 630. The pressure relief cover 620 and the bottom cover 630 are respectively arranged at both ends of the housing 510, and the pressure relief cover 620 is embedded in the sealing cavity 512 and abuts against the positive electrode of the battery cell 400. The sealing ring 610 is arranged in the sealing cavity 512 and is located between the pressure relief cover 620 and the sealing cavity 512.

[0074] It should be noted that during the charging process of the battery cell 110, the internal temperature of the battery rises sharply, and the electrolyte will decompose to generate a large amount of gas, thereby causing the internal pressure of the battery to rise rapidly. When the pressure rises to the bearing limit of the battery outer shell, the generated gas will burst open the battery outer shell and cause an explosion. In the above solution, by opening the explosion-proof grooves 514 on the outer wall of the housing 510, the structural strength of the housing 510 is reduced, that is, the ability of the housing 510 to resist the internal pressure is reduced. Before the internal pressure of the battery reaches the critical value of explosion, the housing 510 will crack along the explosion-proof grooves 514, and the internal gas of the battery will leak from the cracked part, reducing the explosion impact force and avoiding harm to users or causing a fire.

[0075] Please refer to Figure 8, and multiple arc-shaped gaskets 520 are provided on the inner wall of the shell 510. When the battery expands, the arc-shaped gaskets 520 move away from each other under the action of the internal pressure of the battery. Since the explosion-proof groove 514 points to the gap between two adjacent arc-shaped gaskets 520, when two adjacent arc-shaped gaskets 520 separate, the outward thrust acting on the inner wall of the shell 510 will cause stress concentration in the explosion-proof groove 514, thereby making the shell 510 more likely to crack.

[0076] See also Figure 9 At the same time, since the edges of each two adjacent arc-shaped gaskets 520 are in contact with each other, when the battery is subjected to external pressure, the pressure acts on the arc-shaped gasket 520 and is dispersed to the other two arc-shaped gaskets 520 that are in contact with the arc-shaped gasket 520, that is, multiple arc-shaped gaskets 520 form an auxiliary support structure on the inner wall of the shell 510 to improve the pressure resistance of the shell 510, that is, the anti-expansion ability of the shell 510 is weakened by the explosion-proof structure composed of the arc-shaped gaskets 520 and the explosion-proof groove 514, and multiple arc-shaped gaskets 520 assist the shell 510 in resisting external pressure in the shell 510, thereby improving the safety performance of the lithium battery cell 110.

[0077] The following describes in detail the stress conditions of the housing 510 under the two states of internal expansion force and external pressure with reference to the accompanying drawings:

[0078] See also Figure 8 , battery failure causes the internal pressure to rise rapidly, generating multiple radially distributed expansion forces F1 pointing from the center of the battery to the outside of the battery. Under the action of the expansion force F1, the arc-shaped gaskets 520 move away from each other and are transmitted to the shell 510, and an expansion component force F2 is generated on both sides of one of the explosion-proof grooves 514. The two expansion components F2 are centered on the explosion-proof groove 514 and in opposite directions. As the internal pressure of the battery increases, the expansion component forces F2 acting on both sides of the explosion-proof groove 514 increase accordingly, and then the shell 510 is torn along both sides of the explosion-proof groove 514. At this time, the internal gas of the battery leaks along the cracked position, achieving the purpose of pressure relief, thereby reducing the ability of the shell 510 to resist expansion.

[0079] See also Figure 9, when the battery receives an external pressure F3, the pressure F3 acts on one of the arc-shaped gaskets 520 through the housing 510, causing the arc-shaped gasket 520 to tend to move towards the center of the battery. Since the edges of the multiple arc-shaped gaskets 520 are in contact with each other, at this time, the pressure F3 will generate a pressure component F4, and the pressure component F4 acts on the two arc-shaped gaskets 520 that are in contact with this arc-shaped gasket 520. At the same time, these two arc-shaped gaskets 520 generate reaction forces to resist the pressure component F4, that is, the external pressure F3 is dispersed among the multiple arc-shaped gaskets 520, assisting the housing 510 to resist the pressure F3 to prevent the housing 510 from deforming, that is, improving the pressure resistance of the housing 510.

[0080] Further, the battery cell 400 includes a positive electrode sheet, a separator, and a negative electrode sheet. The positive electrode sheet, the separator, and the negative electrode sheet are sequentially laminated and wound into a columnar structure, and the negative electrode sheet is located on the outermost side. The multiple arc-shaped gaskets 520 are all in contact with the negative electrode sheet.

[0081] Further, please refer to Figure 8 , in order to improve the anti-expansion performance of the position where the explosion-proof groove 514 is located and reduce the necessary depth of the explosion-proof groove 514, the groove width of the explosion-proof groove 514 decreases from the side close to the outer wall of the housing 510 to the side close to the inner wall of the housing 510.

[0082] Please refer to Figure 6 , in order to improve the anti-expansion performance of the position where the explosion-proof groove 514 is located, the length of the explosion-proof groove 514 is greater than the length of the arc-shaped gasket 520.

[0083] In order to improve the supporting force of the arc-shaped gasket 520 on the housing 510, the arc-shaped gaskets 520 are arranged in a circumferential array centered on the axis line of the battery cell 400, and the multiple arc-shaped gaskets 520 are in contact end to end.

[0084] In order to improve the overall structural strength of the battery cell 110, a positioning groove 515 is opened at one end of the housing 510 away from the sealing cavity 512, and the edge of the bottom cover 630 is embedded in the positioning groove 515.

[0085] In order to prevent the battery cell 400 from short-circuiting, the outer shell 500 further includes a bottom cushion block 230. The bottom cushion block 230 is arranged in the main receiving cavity 513, and the bottom cover 630 and the battery cell 400 are respectively in contact with the two opposite side surfaces of the bottom cushion block 230.

[0086] Further, it further includes a packaging film, and the packaging film is wrapped around the outer wall of the outer shell 500.

[0087] Please refer to Figure 6, in order to improve the airtightness of the lithium battery cell 110, the sealing ring 610 includes an elastic sleeve 611 and a barrier ring 612. The elastic sleeve 611 is sleeved on the top cover. The two ends of the elastic sleeve 611 are open. The barrier ring 612 is arranged on the side of the elastic sleeve 611 close to the main accommodation cavity 513, and the barrier ring 612 is in close contact with the partition part 511.

[0088] The above battery cell 110 is provided with a battery core 400, a housing 500 and a cover 600. An explosion-proof groove 514 is opened on the outer wall of the housing 500 to reduce the structural strength of the housing 500. Before the internal pressure of the battery rises to the explosion critical value, it can crack and relieve pressure along the extension direction of the explosion-proof groove 514. And a plurality of arc-shaped gaskets 520 are arranged inside the housing 500 to make up for the compressive capacity of the housing 500. The pressure borne by the battery housing 500 is shared by each arc-shaped gasket 520, and when the battery expands, it assists in applying an external force outward, reducing the anti-expansion capacity of the housing 500, avoiding the explosion of the battery due to excessive internal pressure when the battery cell 110 fails, and improving the safety performance of the battery cell 110.

[0089] Further, when the explosion-proof groove 514 of the battery cell 110 cracks, it is scrapped. If the lithium battery module 10 needs to be used in a relatively harsh environment, the frequency of abnormal temperature rise inside the battery cell 110 will inevitably be relatively high, making the internal pressure of the battery cell 110 unstable, and the service life of the battery cell 110 will be shortened accordingly. In order to improve the service life of the battery cell 110, the battery cell 110 needs to have a certain pressure relief function to prevent the battery cell 110 from expanding and deforming due to internal pressure changes.

[0090] The pressure relief cover 620 includes a current collecting shaft 621, a tray 622, a reed 623 and a cap 624. A plurality of pressure relief holes 624a are opened on the cap 624. The cap 624 covers the tray 622, and the edges of the cap 624 and the tray 622 are both embedded in the sealing cavity 512. The reed 623 is arranged between the cap 624 and the tray 622. The tray 622 is provided with a through hole 622a, a gear slot 622b and a plurality of air vent grooves 622c. The plurality of air vent grooves 622c are arranged around the gear slot 622b, and each air vent groove 622c is communicated with the gear slot 622b. The through hole 622a is communicated with the gear slot 622b. The current collecting shaft 621 passes through the through hole 622a and abuts against the battery core. The reed 623 abuts against the current collecting shaft 621 for driving the current collecting shaft 621 to be in close contact with the groove wall of the gear slot 622b.

[0091] In order to better illustrate the pressure relief method of the above pressure relief cover 620 to better understand the concept of the above pressure relief cover 620.

[0092] Please refer toFigure 10 and Figure 11 , the pressure relief cover 620 includes a current collecting shaft 621, a tray 622, a reed 623 and a cap 624. A plurality of pressure relief holes 624a are formed in the cap 624. In one embodiment, there are 6 pressure relief holes 624a. The cap 624 covers the tray 622, and the edges of the cap 624 and the tray 622 are both embedded in the seal cavity 512, that is, the cap 624 and the tray 622 are fixed simultaneously through the seal cavity 512, and an inner wall of the cap 624 and the tray 622 together enclose a pressure relief inner cavity 700. The reed 623 is disposed between the cap 624 and the tray 622, that is, the reed 623 is located in the pressure relief inner cavity 700.

[0093] Please refer to Figure 10 and Figure 11 , a through hole 622a, a gear position groove 622b and a plurality of air permeable grooves 622c are formed in the tray 622. The plurality of air permeable grooves 622c are arranged around the gear position groove 622b, and each air permeable groove 622c communicates with the gear position groove 622b. The gear position groove 622b and the plurality of air permeable grooves 622c are both located in the pressure relief inner cavity 700. The through hole 622a communicates with the gear position groove 622b. The current collecting shaft 621 passes through the through hole 622a and abuts against the battery cell 400. The reed 623 abuts against the current collecting shaft 621 to drive the current collecting shaft 621 to closely adhere to the groove wall of the gear position groove 622b, that is, the elastic force of the reed 623 acts on the end face of the current collecting shaft 621, and the direction of the elastic force is from the position where the reed 623 is located to the position where the battery cell 400 is located, so that the current collecting shaft 621 closely adheres to the groove wall of the gear position groove 622b.

[0094] The working principle of the pressure relief cover 620 is introduced as follows:

[0095] Please refer to Figure 12 , when the battery cell 110 is working normally, the pressure in the inner cavity of the housing 510 is lower than the elastic force exerted by the reed 623 on the current collecting shaft 621. Therefore, the current collecting shaft 621 is pressed by the elastic force in the gear position groove 622b and closely adheres to the groove wall of the gear position groove 622b. At this time, the current collecting shaft 621 closes the through hole 622a. At this time, the pressure relief inner cavity 700 and the inner cavity of the housing 510 are blocked by the current collecting shaft 621, and the gas in the housing 510 cannot enter the pressure relief inner cavity 700.

[0096] Please refer to Figure 13, when an abnormality occurs in the battery cell 110, the air pressure inside the housing 510 rapidly increases. If the pressure acting on the current collector shaft 621 at this time is greater than the elastic force provided by the reed 623 to the current collector shaft 621, then the direction of the resultant force of the external forces acting on the current collector shaft 621 at this time is from the position where the battery cell 400 is located to the position where the reed 623 is located, causing the current collector shaft 621 to move away from the battery cell 400, that is, the current collector shaft 621 is no longer in contact with the groove wall of the gear position groove 622b. At this time, the through hole 622a is no longer blocked by the current collector shaft 621, and the inner cavity of the housing 510 is in communication with the external air. The high-pressure gas first enters the gear position groove 622b through the through hole 622a, and then flows into the pressure relief inner cavity 700 through the respective ventilation grooves 622c communicating with the gear position groove 622b, and is ejected through the multiple pressure relief holes 624a on the cap 624 to complete the pressure relief.

[0097] After the pressure relief cover 620 is activated, the internal pressure of the housing 510 begins to decrease. Under the action of the elastic force provided by the reed 623, the current collector shaft 621 moves towards the battery cell 400 and closely adheres to the groove wall of the gear position groove 622b again, blocking the inner cavity of the housing 510 from the pressure relief inner cavity 700 to avoid further leakage of the electrolyte, thereby avoiding dangerous accidents such as expansion and explosion when the battery cell 110 is abnormal, and improving the safety performance of the nickel-metal hydride battery.

[0098] Please refer to Figure 11 , in order to improve the pressure relief effect, multiple ventilation grooves 622c are distributed in a circular array centered on the gear position groove 622b.

[0099] Please refer to Figure 11 , in order to improve the pressure relief effect and avoid the phenomenon of jamming when the current collector shaft 621 moves, the gear position groove 622b includes a sealing portion 810 and a pressure relief portion 820. The pressure relief portion 820 is in communication with the sealing portion 810, and the pressure relief portion 820 is located on the side close to the reed 623. The inner wall of the sealing portion 810 is in close contact with the outer wall of the current collector shaft 621, and there is a gap between the inner wall of the pressure relief portion 820 and the outer wall of the current collector shaft 621. And the diameter of the pressure relief portion 820 increases from the end close to the sealing portion 810 to the end close to the reed 623.

[0100] Furthermore, please refer to Figure 11 , the reed 623 includes an outer ring 623a and multiple elastic teeth 623b. The multiple elastic teeth 623b are arranged on the inner wall of the outer ring 623a, and all the multiple elastic teeth 623b are in contact with the end face of the current collector shaft 621.

[0101] [[ID=2l]]In one embodiment, please refer to Figure 12, the current collecting shaft 621 includes a guide rod 621a, a flange 621b and a sealing sleeve 621c. The guide rod 621a is disposed on the flange 621b. The guide rod 621a passes through the through hole 622a. The sealing sleeve 621c is sleeved on the flange 621b, and the outer wall of the sealing sleeve 621c is used to abut against the inner wall of the gear position groove 622b. The reed 623 abuts against the flange 621b. And the diameter of the guide rod 621a is smaller than the aperture of the through hole 622a.

[0102] Figure 10 The above-mentioned battery cell 110 is provided with a battery core 400, a housing 510 and a pressure relief cover 620. The position of the pressure relief cover 620 is provided with a pressure relief structure. When the internal pressure of the battery rises due to a battery failure, it is automatically activated to guide the internal high-pressure gas, protect the battery, prevent the battery from swelling and exploding, and improve the safety performance of the nickel-metal hydride battery.

[0103] The above embodiments only represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

Claims

1. A lithium battery module, characterized in that, Comprising: A lithium battery pack, the lithium battery pack including a plurality of battery cells, each battery cell including: a battery core, a housing, and a cover. The housing includes a shell and a plurality of arc-shaped gaskets. The shell is provided with a partition portion, a sealing cavity, and a main receiving cavity. The partition portion is located on the inner wall of the shell. A plurality of the arc-shaped gaskets are all disposed in the main receiving cavity. The edges of every two adjacent arc-shaped gaskets are in contact with each other. A gap is provided between every two adjacent arc-shaped gaskets. A plurality of explosion-proof grooves are formed on the outer wall of the shell, and the plurality of explosion-proof grooves are respectively and correspondingly oriented towards the plurality of gaps; The cover includes a sealing ring, a pressure relief cover, and a bottom cover. The pressure relief cover and the bottom cover are respectively disposed at both ends of the shell, and the pressure relief cover is embedded in the sealing cavity and abuts against the positive electrode of the battery core. The sealing ring is disposed in the sealing cavity and is located between the pressure relief cover and the sealing cavity; Two detachable holders, the two detachable holders are respectively installed on the positive electrode and the negative electrode of the lithium battery pack, and each detachable holder includes a plurality of splicing monomers; In one of the splicing monomers, the splicing monomer includes a splicing base and a plurality of docking buttons. The splicing base is provided with a receiving cavity and a welding through hole, and the welding through hole communicates with the receiving cavity. A plurality of the docking buttons are all disposed on the outer wall of the splicing base. The plurality of docking buttons are arranged in a circumferential array centered on the axis of the welding through hole, and each docking button includes a male button and a female button; A plurality of conductive patches, the plurality of conductive patches are respectively and correspondingly disposed in the plurality of splicing bases, and the plurality of conductive patches are in contact with each other.

2. The lithium battery module according to claim 1, wherein The splicing base is provided with a pre-embedded groove, the pre-embedded groove is located on the inner wall of the receiving cavity and communicates with the welding through hole, and the conductive patch is embedded in the pre-embedded groove.

3. The lithium battery module according to claim 2, wherein The conductive patch includes an intermediate guiding portion and connecting portions located at both ends of the intermediate guiding portion. The intermediate guiding portion is located in the pre-embedded groove, and the connecting portions are located on the outer wall of the splicing base.

4. The lithium battery module according to claim 3, characterized in that The connecting portion is located between the male button and the female button.

5. The lithium battery module according to claim 3, wherein A bending area is provided on the connecting portion.

6. The lithium battery module according to claim 2, wherein The pre-embedded groove includes a first installation area and a second installation area, and the first installation area and the second installation area are respectively used for accommodating one conductive patch.

7. The lithium battery module according to claim 6, wherein The depth of the first installation area is greater than the depth of the second installation area.

8. The lithium battery module according to claim 1, wherein The splicing base further includes a plurality of elastic abutting strips, and the plurality of elastic abutting strips are spaced apart in the receiving cavity.

9. The lithium battery module according to claim 8, wherein, The plurality of elastic abutting strips are arranged in a circumferential array centered on the axis of the welding through hole.

10. The lithium battery module according to claim 8, wherein, There are 4 elastic abutting strips.

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