Battery cell structure and battery

Abstract

The utility model relates to the technical field of batteries, and discloses a battery cell structure and a battery. The insulating part is arranged on one side of the first plate body along the first direction; one side, in the first direction, of the end plate abuts against the first plate body, and the other side of the end plate is suitable for abutting against the pole group; a containing space is defined by the inner side wall of the end plate and located on the side, close to the first plate body in the first direction, of the end plate, and the containing space is suitable for containing an insulating part. According to the battery cell structure provided by the utility model, the inner side walls of the end plates form the accommodating space through enclosing, so that the insulating part is completely arranged in the accommodating space in the assembly process so as to be limited, the insulating part is prevented from deviating, and meanwhile, the first plate body is better in strength and planeness compared with lower plastic cement, so that the insulating part is prevented from being damaged. The first plate body is not prone to deformation, the end plate is directly connected with the first plate body in an abutting mode, and the risk caused by matching displacement of the end plate and the lower plastic is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and particularly relates to a cell structure and a battery. Background Art

[0002] With the increasing maturity of lithium-ion battery technology, lithium-ion batteries are widely used as power batteries in electric vehicles and energy storage fields, and the requirements for the use performance and safety of lithium-ion batteries are increasing day by day. The lithium battery cell is a core component for the safety and assembly of the battery pack, and its structural design is crucial for the safety of the cell. However, in the existing cell structure, it is easy for the cooperation between the end plate and the lower plastic to shift, affecting the safety of the cell. Summary of the Utility Model

[0003] In view of this, the utility model provides a cell structure and a battery to solve the problem that the cooperation between the end plate and the lower plastic in the existing cell structure is easy to shift, affecting the safety of the cell.

[0004] In a first aspect, the utility model provides a cell structure, comprising:

[0005] A first plate body;

[0006] An insulating member disposed on one side of the first plate body along a first direction;

[0007] An end plate, one side of which along the first direction abuts against the first plate body, and the other side is adapted to abut against the electrode group; an accommodation space is formed by enclosing the inner side wall of the end plate, the accommodation space is located on the side of the end plate close to the first plate body along the first direction, and the insulating member is adapted to be accommodated in the accommodation space.

[0008] Advantageous Effects: In the cell structure provided by the utility model, the inner side wall of the end plate forms an accommodation space by enclosing, so that the insulating member is completely placed inside the accommodation space during the assembly process to limit the insulating member and prevent the insulating member from shifting. At the same time, since the first plate body has better strength and flatness than the lower plastic, the first plate body is not easily deformed, and the end plate is directly abutted against the first plate body, avoiding the risk of cooperation shift between the end plate and the lower plastic.

[0009] In an optional embodiment, the end plate includes two first side walls oppositely arranged along a second direction and two second side walls oppositely arranged along a third direction, and the first side walls and the second side walls are adapted to jointly enclose the accommodation space;

[0010] The insulating member has a clearance fit with the first side wall and / or the second side wall.

[0011] Beneficial effects: By adopting a clearance fit between the insulating part and the first side wall and / or the second side wall of the end plate, during the assembly process, it is only necessary to completely place the insulating part in the accommodation space and then directly abut the end plate against the first plate body, which is beneficial to simplifying the assembly process and facilitating automated production.

[0012] In an alternative embodiment, the clearance between one side of the insulating part along the second direction and the first side wall is L, and L satisfies 0 ≤ L ≤ 2 mm;

[0013] And / or, the clearance between one side of the insulating part along the third direction and the second side wall is W, and W satisfies 0 ≤ W ≤ 2 mm.

[0014] Beneficial effects: It can not only simplify the assembly process and facilitate automated production, but also prevent the tab from protruding through the clearance, avoiding the risk of the tab overlapping with the housing, which is beneficial to improving the safety of the battery cell.

[0015] In an alternative embodiment, the battery cell structure further includes a housing, the inner wall of the housing is adapted to jointly enclose a receiving cavity with the first plate body, and the receiving cavity is adapted to accommodate the electrode assembly;

[0016] On at least one side wall of the housing along the third direction, a boss is formed, and an explosion-proof hole communicating with the receiving cavity is provided on the boss; the battery cell structure further includes an explosion-proof valve, at least a part of the explosion-proof valve is arranged on the side of the boss facing the receiving cavity, and the explosion-proof valve seals the explosion-proof hole.

[0017] Beneficial effects: The explosion-proof valve is arranged on at least one side wall of the housing along the third direction. When the battery cell undergoes thermal runaway, it can achieve rapid exhaust at the path end and simultaneously achieve gas-electric separation.

[0018] In an alternative embodiment, the battery cell structure further includes a side plate, the side plate is arranged between the electrode assembly and the inner wall of the housing, and the side plate is arranged opposite to the explosion-proof valve;

[0019] An exhaust through-hole is provided on the side plate, and the exhaust through-hole communicates with the explosion-proof hole.

[0020] Beneficial effects: On the one hand, the displacement of the electrode assembly is restricted by the side plate to prevent the electrode assembly from moving around. At the same time, the side plate is arranged opposite to the explosion-proof valve. When the battery cell is abnormal, the thermal runaway gas can be quickly discharged to the explosion-proof hole through the exhaust through-hole in a timely manner, enabling the explosion-proof valve to detonate and release pressure in a timely manner, thereby achieving rapid exhaust at the path end and simultaneously achieving gas-electric separation.

[0021] In an alternative embodiment, the side plate includes a second plate body and a step portion protruding from one side of the second plate body away from the electrode assembly along the third direction;

[0022] One side of the stepped portion away from the electrode group along the third direction abuts against the inner wall of the housing, so that an exhaust space is formed at an interval between the second plate body and the inner wall of the housing along the third direction, and the exhaust space is communicated with the exhaust through hole and the explosion-proof hole at the same time.

[0023] Advantageous effects: By providing a stepped portion on one side of the second plate body away from the electrode group along the third direction, and abutting the stepped portion against the inner wall of the housing, the second plate body is arranged at an interval from the inner wall of the housing. On the one hand, the second plate body can avoid the explosion-proof valve, preventing the second plate body from damaging the explosion-proof valve. On the other hand, an exhaust space can be formed between the second plate body and the inner wall of the housing, ensuring rapid exhaust at the path end.

[0024] In an alternative embodiment, a guiding portion is formed on one side of the stepped portion in the first direction, and the guiding portion is adapted to guide the side plate into the accommodating cavity of the housing.

[0025] Advantageous effects: By guiding the side plate into the accommodating cavity of the housing through the guiding portion, it is beneficial for the side plate to smoothly enter the housing along with the electrode group.

[0026] In an alternative embodiment, the battery cell structure further includes an insulating film, and the insulating film is adapted to wrap the electrode group in a ring shape;

[0027] The side wall of the end plate is hot melt welded to the insulating film.

[0028] Advantageous effects: The insulating member is completely built into the accommodating space of the end plate, and the end plate directly abuts against the first plate body, eliminating the fitting gap between the insulating member and the end plate in the first direction, effectively avoiding the risk of the pole ear overlapping with the housing, thereby realizing insulation protection for the pole ear through the end plate; the first side wall and the second side wall of the end plate are appropriately extended along the first direction, which is more conducive to the positioning and hot melting of the insulating film; at the same time, after the end plate and the insulating film are hot melted, the overlapping of the pole ear and the housing is more effectively avoided, and the insulating film and the end plate can provide double insulation protection for the pole ear.

[0029] In an alternative embodiment, the side plate is arranged on the side of the insulating film away from the electrode group.

[0030] Advantageous effects: Thus, it is possible to avoid the insulating film from blocking the exhaust through hole and the exhaust space.

[0031] In a second aspect, the present utility model further provides a battery, including: a battery body, and the battery cell structure as described above.

[0032] Advantageous effects: The battery in the second aspect includes the battery cell structure in the first aspect. Therefore, the battery in the second aspect includes all the advantageous effects of the battery cell structure in the first aspect. Description of the Drawings

[0033] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0034] Figure 1 It is the first assembly drawing of the end plate, the first plate body and the insulating member of a battery cell structure according to an embodiment of the present invention;

[0035] Figure 2 It is the second assembly drawing of the end plate, the first plate body and the insulating member of a battery cell structure according to an embodiment of the present invention;

[0036] Figure 3 It is Figure 2 The partial enlarged schematic view at A in

[0037] Figure 4 It is the exploded structure schematic view of a battery cell structure according to an embodiment of the present invention;

[0038] Figure 5 It is Figure 4 The partial enlarged schematic view at B in

[0039] Figure 6 It is the assembly drawing of a battery cell structure according to an embodiment of the present invention;

[0040] Figure 7 It is Figure 6 The partial enlarged schematic view at C in

[0041] Figure 8 It is Figure 6 The partial enlarged schematic view at D in

[0042] Explanation of reference numerals:

[0043] 10. First plate body;

[0044] 20. Insulating member;

[0045] 30. End plate; 301. Accommodating space; 31. First side wall; 32. Second side wall;

[0046] 40. Electrode group;

[0047] 50. Housing; 51. Boss; 52. Explosion-proof hole;

[0048] 60. Explosion-proof valve;

[0049] 70. Side plate; 701. Exhaust through-hole; 702. Exhaust space; 71. Second plate body; 72. Step portion; 73. Guide portion;

[0050] 80. Insulating film. Detailed implementation manners

[0051] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0052] The following will describe the embodiments of the present utility model in conjunction with Figures 1 to 8 to describe the embodiments of the present utility model.

[0053] According to an embodiment of the present utility model, on the one hand, a battery cell structure is provided, including:

[0054] A first plate body 10, which can be made of aluminum material;

[0055] An insulating member 20, which can adopt a plastic material. The insulating member 20 is disposed on one side of the first plate body 10 along the first direction;

[0056] An end plate 30. Please also refer to Figure 1 , Figure 2 and Figure 3 as shown. One side of it along the first direction abuts against the first plate body 10, and the other side is adapted to abut against the electrode group 40; an accommodation space 301 is formed by enclosing the inner side wall of the end plate 30. The accommodation space 301 is located on the side of the end plate 30 along the first direction close to the first plate body 10, and the insulating member 20 is adapted to be accommodated in the accommodation space 301.

[0057] In the battery cell structure in the related art, a lower plastic is provided between the end plate and the light aluminum plate. The end plate is in surface contact and cooperation with the lower plastic, and the light aluminum plate is welded to the housing. The light aluminum plate presses the lower plastic, and then the lower plastic presses the end plate, so as to fix the end plate to the electrode group; since the lower plastic itself is easily deformed by the extrusion of the end plate and the light aluminum plate, and there is an assembly gap between the electrode group and the housing, the electrode group is prone to displacement, thereby increasing the risk of the tab and the housing overlapping.

[0058] For the battery cell structure provided by the present utility model, the inner sidewall of the end plate 30 encloses to form an accommodation space 301, so that during the assembly process, the insulating member 20 is completely placed inside the accommodation space 301 to limit the insulating member 20 and prevent the insulating member 20 from shifting. At the same time, since the first plate body 10 has better strength and flatness than the lower plastic, the first plate body 10 is not easily deformed. The end plate 30 is directly in contact with the first plate body 10, avoiding the risk of displacement due to the cooperation between the end plate and the lower plastic.

[0059] In some embodiments, please also refer to Figure 1 、 Figure 2 and Figure 3 As shown, the end plate 30 includes two first sidewalls 31 oppositely arranged along the second direction and two second sidewalls 32 oppositely arranged along the third direction. The first sidewalls 31 and the second sidewalls 32 are adapted to jointly enclose to form the accommodation space 301;

[0060] A clearance fit is provided between the insulating member 20 and the first sidewall 31 and / or the second sidewall 32.

[0061] In this embodiment, by adopting a clearance fit between the insulating member 20 and the first sidewall 31 and / or the second sidewall 32 of the end plate 30, during the assembly process, it is only necessary to completely place the insulating member 20 inside the accommodation space 301 and then directly contact the end plate 30 with the first plate body 10, which is beneficial to simplifying the assembly process and facilitating automated production.

[0062] In some embodiments, please refer to Figure 1 As shown, the gap between one side of the insulating member 20 along the second direction and the first sidewall 31 is L, and L satisfies 0 ≤ L ≤ 2 mm;

[0063] And / or, please refer to Figure 3 As shown, the gap between one side of the insulating member 20 along the third direction and the second sidewall 32 is W, and W satisfies 0 ≤ W ≤ 2 mm.

[0064] It should be noted that the gap L between the insulating member 20 and the first sidewall 31 and the gap W between the insulating member 20 and the second sidewall 32 cannot be too large, otherwise it is easy for the tab to extend out of the gap, increasing the risk of the tab overlapping with the housing. Therefore, L and W need to satisfy L ≤ 2 mm and W ≤ 2 mm; in order to facilitate the insulating member 20 to more smoothly enter the accommodation space 301 of the end plate 30 during the assembly process, L and W also need to satisfy L ≥ 0 and W ≥ 0.

[0065] In this embodiment, the gap L between one side of the insulating member 20 in the second direction and the first side wall 31 satisfies 0 ≤ L ≤ 2 mm, and / or the gap W between one side of the insulating member 20 in the third direction and the second side wall 32 satisfies 0 ≤ W ≤ 2 mm, which can not only simplify the assembly process and facilitate automated production, but also prevent the tab from protruding through the gap, avoiding the risk of the tab overlapping with the housing, and is beneficial to improving the safety of the battery cell.

[0066] Preferably, L satisfies 0.05 mm ≤ L ≤ 2 mm, and W satisfies 0.05 mm ≤ W ≤ 2 mm.

[0067] In some embodiments, please refer to Figure 4 as shown, the battery cell structure further includes a housing 50. The inner wall of the housing 50 is adapted to jointly enclose a receiving cavity with the first plate body 10, and the receiving cavity is adapted to receive the electrode assembly 40;

[0068] A boss 51 is formed on at least one of the side walls of the housing 50 in the third direction, and an explosion-proof hole 52 communicating with the receiving cavity is formed in the boss 51; the battery cell structure further includes an explosion-proof valve 60, and at least a part of the explosion-proof valve 60 is disposed on the side of the boss 51 facing the receiving cavity, and the explosion-proof valve 60 seals the explosion-proof hole 52.

[0069] In the battery cell structure in the related art, the explosion-proof valve is usually disposed on the cover plate. On the one hand, the exhaust passage is prone to blockage, and on the other hand, the exhaust path is long, and it is difficult to quickly discharge the thermal runaway gas in time when the battery cell is abnormal.

[0070] In this embodiment, the explosion-proof valve 60 is disposed on at least one of the side walls of the housing 50 in the third direction. When the battery cell undergoes thermal runaway, it can achieve rapid exhaust at the end of the path and simultaneously achieve gas-electric separation.

[0071] In some embodiments, please refer to Figure 4 as shown, the battery cell structure further includes a side plate 70. The side plate 70 is disposed between the electrode assembly 40 and the inner wall of the housing 50, and the side plate 70 is disposed opposite to the explosion-proof valve 60;

[0072] Please also refer to Figure 5 as shown, an exhaust through hole 701 is formed in the side plate 70, and the exhaust through hole 701 communicates with the explosion-proof hole 52.

[0073] In this embodiment, by disposing the side plate 70 between the electrode assembly 40 and the inner wall of the housing 50 and forming the exhaust through hole 701 in the side plate 70, on the one hand, the displacement of the electrode assembly 40 is restricted by the side plate 70 to prevent the electrode assembly 40 from moving around. At the same time, the side plate 70 is disposed opposite to the explosion-proof valve 60. When the battery cell is abnormal, the thermal runaway gas can be quickly discharged to the explosion-proof hole 52 through the exhaust through hole 701 in time, so that the explosion-proof valve 60 detonates in time to release pressure, thereby achieving rapid exhaust at the end of the path and simultaneously achieving gas-electric separation.

[0074] In some embodiments, please refer to Figure 5 and Figure 7 As shown, the side plate 70 includes a second plate body 71 and two stepped portions 72 formed by protruding from one side of the second plate body 71 away from the electrode group 40 in the third direction. The two stepped portions 72 are relatively spaced apart along the second direction on the second plate body 71;

[0075] Please refer to Figure 8 As shown, the side of the stepped portion 72 away from the electrode group 40 in the third direction abuts against the inner wall of the housing 50, so that an exhaust space 702 is formed at an interval between the second plate body 71 and the inner wall of the housing 50 in the third direction. The exhaust space 702 is communicated with the exhaust through hole 701 and the explosion-proof hole 52 at the same time.

[0076] In this embodiment, by providing the stepped portion 72 on the side of the second plate body 71 away from the electrode group 40 in the third direction and abutting the stepped portion 72 against the inner wall of the housing 50, the second plate body 71 is arranged at an interval from the inner wall of the housing 50. On the one hand, the second plate body 71 can avoid the explosion-proof valve 60 and prevent the second plate body 71 from damaging the explosion-proof valve 60. On the other hand, an exhaust space 702 can be formed between the second plate body 71 and the inner wall of the housing 50 to ensure rapid exhaust at the path end.

[0077] Furthermore, the stepped portion 72 and the second plate body 71 are of an integrally formed structure.

[0078] In some embodiments, please refer to Figure 5 As shown, a guiding portion 73 is formed on one side of the stepped portion 72 in the first direction. During the assembly process, the side plate 70 is guided into the accommodating cavity of the housing 50 through the guiding portion 73, which is beneficial to the smooth insertion of the side plate 70 and the electrode group 40 into the housing.

[0079] In some embodiments, please refer to Figure 5 As shown, the battery cell structure further includes an insulating film 80, and the insulating film 80 is adapted to wrap the electrode group 40;

[0080] Please refer to Figure 6 and Figure 7 As shown, the first side wall 31 and the second side wall 32 of the end plate 30 are heat-sealed to the insulating film 80.

[0081] In the cell structure in the related art, the light aluminum plate presses the lower plastic along the first direction, and then the lower plastic presses the end plate along the first direction, so as to fix the end plate to the pole group. When the insulating film and the end plate are heat-melted, since the lower plastic itself is easily deformed and displaced by extrusion, and at the same time due to the influence of assembly deviation, there is a gap of 1 mm - 1.5 mm between the lower plastic and the end plate along the first direction, and the tab is likely to run out from the gap between the lower plastic and the end plate, unable to achieve complete insulation protection, and there is a risk of the tab overlapping with the housing.

[0082] It should be noted that in this embodiment, since the insulating member 20 is completely built into the accommodation space 301 of the end plate 30 during assembly, therefore, in the process of component design and processing, compared with the cell structure before improvement, the size of the insulating member 20 along the first direction can be appropriately reduced in this embodiment, and at the same time, the sizes of the first side wall 31 and the second side wall 32 of the end plate 30 along the first direction can be appropriately extended. On the one hand, it ensures that the insulating member 20 is completely built into the accommodation space 301, so that the end plate 30 is in direct contact with the first plate body 10, avoiding the risk of displacement due to the cooperation of the end plate and the lower plastic. On the other hand, the area of the outer peripheral side plane of the end plate 30 is larger, which is more conducive to the positioning and heat melting of the insulating film 80.

[0083] In this embodiment, the insulating member 20 is completely built into the accommodation space 301 of the end plate 30, and the end plate 30 is in direct contact with the first plate body 10, eliminating the fitting gap between the insulating member 20 and the end plate 30 in the first direction, effectively avoiding the risk of the tab overlapping with the housing, so as to realize the insulation protection of the tab through the end plate 30; the first side wall 31 and the second side wall 32 of the end plate 30 are appropriately extended along the first direction, which is more conducive to the positioning and heat melting of the insulating film 80; at the same time, after the end plate 30 and the insulating film 80 are heat-melted, the risk of the tab overlapping with the housing is more effectively avoided, and the insulating film 80 and the end plate 30 can provide double insulation protection for the tab.

[0084] In some embodiments, please refer to Figure 5 As shown, the side plate 70 is disposed on the side of the insulating film 80 away from the pole group 40, so as to prevent the insulating film 80 from blocking the exhaust through hole 701 and the exhaust space 702.

[0085] According to an embodiment of the present invention, on the other hand, a battery is further provided, including: a battery body, and the cell structure as described above.

[0086] The battery in this embodiment includes the cell structure as described above. Therefore, the battery in this embodiment has all the beneficial effects of the cell structure as described above.

[0087] Although embodiments of the present utility model have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present utility model, and such modifications and variations fall within the scope defined by the appended claims.

Claims

1. A battery cell structure, characterized in that: include: A first plate body; An insulating member, disposed on one side of the first plate along the first direction; An end plate, one side of which along the first direction is in contact with the first plate body, and the other side is suitable for being in contact with the pole group; the inner side wall of the end plate encloses a receiving space, and the receiving space is located on the side of the end plate close to the first plate body along the first direction, and the receiving space is suitable for receiving the insulating member.

2. The battery cell structure according to claim 1, characterized in that: The end plate comprises two first side walls arranged opposite to each other along the second direction and two second side walls arranged opposite to each other along the third direction, wherein the first side walls and the second side walls are suitable for jointly enclosing and forming the accommodation space; The insulating member is clearance-fitted with the first side wall and / or the second side wall.

3. The battery cell structure according to claim 2, characterized in that: A gap between one side of the insulating member along the second direction and the first side wall is L, and L satisfies 0≤L≤2mm; And / or, a gap between one side of the insulating member along the third direction and the second side wall is W, and W satisfies 0≤W≤2mm.

4. The battery cell structure according to claim 1, characterized in that: The battery core structure further comprises a shell, the inner wall of which is suitable for being enclosed together with the first plate body to form a receiving cavity, and the receiving cavity is suitable for receiving the electrode group; A boss is formed on at least one of the side walls of the shell along the third direction, and an explosion-proof hole connected to the accommodating cavity is formed on the boss; the battery cell structure also includes an explosion-proof valve, at least part of which is arranged on a side of the boss facing the accommodating cavity, and the explosion-proof valve seals the explosion-proof hole.

5. The battery cell structure according to claim 4, characterized in that: The battery core structure further includes a side plate, which is disposed between the electrode group and the inner wall of the shell, and the side plate is disposed opposite to the explosion-proof valve; An exhaust through hole is provided on the side plate, and the exhaust through hole is communicated with the explosion-proof hole.

6. The battery cell structure according to claim 5, characterized in that: The side plate includes a second plate body and a step portion formed by protruding from one side of the second plate body away from the pole group along the third direction; The step portion abuts against the inner wall of the shell along the third direction away from the pole group, so that an exhaust space is formed between the second plate body and the inner wall of the shell along the third direction, and the exhaust space is connected to the exhaust through hole and the explosion-proof hole at the same time.

7. The battery cell structure according to claim 6, characterized in that: A guide portion is formed on one side of the step portion in the first direction, and the guide portion is suitable for guiding the side plate into the accommodating cavity of the shell.

8. The battery core structure according to any one of claims 5 to 7, characterized in that: The battery core structure further includes an insulating film, and the insulating film is suitable for surrounding the electrode group; The side wall of the end plate is heat-fused to the insulating film.

9. The battery cell structure according to claim 8, characterized in that: The side plate is arranged on a side of the insulating film away from the pole group.

10. A battery, characterized in that: include: A battery body, and a battery core structure as claimed in any one of claims 1 to 9.

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