A battery

Abstract

The application belongs to the technical field of batteries, and discloses a battery, which comprises a pole group, a cover plate assembly and a shell, first assembly grooves are formed in the ends of the two pole groups away from each other, second assembly grooves are formed in the side surfaces of the ends of the two pole groups close to each other, the pole group is provided with a first tab and a second tab, and the surface of the pole group in the second direction is provided with a protruding part; the cover plate assembly comprises a first cover plate body, a second cover plate body and a pole post, the first cover plate body comprises a clamping part, the clamping part is clamped with the protruding part, along the first direction, the surface of the first cover plate body away from the pole group is provided with the pole post, the pole group is clamped with the shell, the first cover plate body and the second cover plate body are surrounded with the shell to form a space for accommodating the pole group, and along the third direction, the surface of the shell away from the pole group is provided with the pole post. In this way, the protection effect of the pole post and the connection strength of the pole group and the cover plate assembly can be improved, and the battery capacity can be improved.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and more particularly to a battery. Background Technology

[0002] Lithium-ion batteries are widely used as power batteries in electric vehicles and energy storage. As lithium-ion battery technology matures, the requirements for the performance and safety of lithium-ion batteries are increasing.

[0003] In related technologies, a battery includes an electrode assembly, a cover plate, and a housing. The cover plate and the housing can enclose a space for accommodating the electrode assembly. The cover plate is usually provided with a terminal post and a rivet block. The end of the electrode assembly is provided with a tab. The electrode assembly and the terminal post are electrically connected through the tab.

[0004] However, most cover plates are flat structures, and the rivet blocks and terminals protrude from the cover plate after assembly. This makes the rivet blocks and terminals susceptible to bumps and damage during transportation, assembly, and other processes, resulting in poor protection for the rivet blocks and cover plates, affecting battery safety. Furthermore, the batteries occupy too much external space, affecting the battery packing rate. The connection strength and space utilization between the cover plate and the electrode pack are low, and uneven force can easily cause electrode damage and misalignment when pushing the electrode pack into the casing, making it difficult to meet the requirements of high capacity and high-rate fast charging. Summary of the Invention

[0005] The purpose of this invention is to provide a battery that solves the problems of poor protection of the cover plate for the poles and rivet blocks, low connection strength between the pole group and the cover plate, and low space utilization.

[0006] To achieve this objective, the present invention adopts the following technical solution: A battery includes: two electrode groups arranged along a first direction, wherein a first mounting groove is formed at the ends of the two electrode groups that are far apart from each other, and a second mounting groove is formed on the side of the ends of the two electrode groups that are close to each other; each electrode group is provided with a first tab and a second tab, the first tab being disposed in the first mounting groove and the second tab being disposed in the second mounting groove; and a protrusion is provided on the surface of the electrode group in a second direction; a cover plate assembly, the cover plate assembly including a first cover plate body, a second cover plate body and a plurality of terminal posts, the first cover plate body being disposed corresponding to the first mounting groove and the second cover plate body being disposed corresponding to the second mounting groove; the first cover plate body including a snap-fit ​​portion, the snap-fit ​​portion engaging with the protrusion. The electrode post disposed in the first assembly slot is electrically connected to the first electrode tab, and the electrode post disposed in the second assembly slot is electrically connected to the second electrode tab. Along the first direction, the surface of the first cover plate body opposite to the electrode assembly protrudes from the electrode post. The electrode assembly is snapped into the housing, and the first cover plate body, the second cover plate body, and the housing enclose a space for accommodating the electrode assembly. Along a third direction, the surface of the housing opposite to the electrode assembly protrudes from the electrode post. The first direction is the thickness direction of the first cover plate body, the second direction is the width direction of the first cover plate body, and the third direction is the length direction of the first cover plate body.

[0007] Preferably, the first assembly groove includes a first part and a second part, the first part being disposed at the end of the electrode group in a first direction, the second part being disposed at the side of the electrode group in a third direction, the first part extending along the third direction, the second part extending along the first direction, and the first electrode tab being disposed in the first part and the second part.

[0008] Preferably, the end of the electrode group is provided with an inclined surface, which is located on the side of the first mounting groove in the third direction. The extension direction of the inclined surface is obliquely intersecting the third direction. The width of the end of the electrode group away from the other electrode group is less than the width of the position where the first mounting groove is opened. The snap-fit ​​part includes a first part and a second part. The inclination angle of the first part is equal to the inclination angle of the inclined surface. The second part is located on the side of the first part away from the first mounting groove.

[0009] Preferably, along the third direction, the length of the second part is L1, the length of the snap-fit ​​part is L2, and the condition 0.7≤L1 / L2≤0.95 is satisfied; and / or, the angle between the inclined surface and the end face of the pole group that is away from the other pole group is N, and the condition 100°≤N≤150° is satisfied.

[0010] Preferably, the cover plate assembly further includes a first welding block and a second welding block. The first welding block is connected to the end of the pole post facing away from the pole group. Along the first direction, the surface of the first cover plate body facing away from the pole group protrudes from the first welding block located in the first assembly groove. Along the third direction, the surface of the housing facing away from the pole group protrudes from the first welding block located in the second assembly groove. The second welding block is connected to the end of the pole post facing the pole group.

[0011] Preferably, the thickness of the first welding block is T1, and satisfies 2mm≤T1≤3.5mm; and / or, the thickness of the second welding block is T2, and satisfies 1.5mm≤T2≤3mm.

[0012] Preferably, the first cover plate body includes a bent portion and a connecting portion, the bent portion and the connecting portion are arranged at positions corresponding to the first assembly groove, and the bent portion is connected to the snap-fit ​​portion.

[0013] Preferably, along the first direction, the height of the bent portion is H1, and satisfies 15mm≤H1≤80mm; and / or, along the second direction, the width of the first cover plate body corresponding to the position of the pole group is B1, and the width of the first welding block is F, and satisfies 5mm≤B1-F≤16mm.

[0014] Preferably, along the third direction, the length of the snap-fit ​​portion is L2, the length of the first cover plate body is A, and the condition 0.35≤L2 / A≤0.75 is met; and / or, along the first direction, the height of the snap-fit ​​portion is E, and the condition 12mm≤E≤40mm is met.

[0015] Preferably, along the third direction, the length of the first cover plate body corresponding to the protrusion position is L3, the length of the first cover plate body is A, and 0.25≤L3 / A≤0.7; and / or, along the second direction, the width of the first cover plate body corresponding to the protrusion position is B2, the width of the first cover plate body corresponding to the pole group position is B1, and 10mm≤B2-B1≤70mm.

[0016] The beneficial effects of this invention are: A battery includes two electrode groups arranged along a first direction, a cover plate assembly, and a housing. A first mounting groove is formed at the ends of the two electrode groups that are far apart from each other, and a second mounting groove is formed on the sides of the ends of the two electrode groups that are close to each other. Each electrode group is provided with a first tab and a second tab, the first tab being disposed within the first mounting groove and the second tab being disposed within the second mounting groove. A protrusion is formed on the surface of each electrode group in a second direction. The cover plate assembly includes a first cover plate body, a second cover plate body, and a plurality of terminal posts. The first cover plate body is disposed corresponding to the first mounting groove, and the second cover plate body is disposed corresponding to the second mounting groove. The first cover plate body includes a snap-fit ​​portion, which engages with the protrusion... The electrode assembly is configured with a snap-fit ​​connection. The electrode post disposed in the first assembly slot is electrically connected to the first electrode lug, and the electrode post disposed in the second assembly slot is electrically connected to the second electrode lug. Along the first direction, the surface of the first cover plate body opposite to the electrode assembly protrudes from the electrode post. The electrode assembly is snap-fitted to the housing. The first cover plate body, the second cover plate body, and the housing enclose a space for accommodating the electrode assembly. Along a third direction, the surface of the housing opposite to the electrode assembly protrudes from the electrode post. The first direction is the thickness direction of the first cover plate body, the second direction is the width direction of the first cover plate body, and the third direction is the length direction of the first cover plate body.

[0017] In this way, placing the terminals in the first and second assembly slots can make full use of the space at the ends and sides of the terminal group, improve space utilization, make the battery structure more compact, and allow the first cover plate body and the shell to protect the terminals, improving the protection effect of the terminals and avoiding bumps and damage during transportation, assembly and other processes, thus improving battery safety. The protrusion can increase the battery capacity and improve the connection strength between the terminal group and the cover plate assembly, preventing damage and movement of the terminal group during the insertion of the shell. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the battery structure in one embodiment of the present invention; Figure 2 This is a cross-sectional view of a battery in one embodiment of the present invention; Figure 3 This is a schematic diagram of the pole group structure in one embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the shell and the second cover plate body in one embodiment of the present invention; Figure 5 This is a schematic diagram of the shell structure in one embodiment of the present invention; Figure 6 This is an exploded view of the housing and the second cover plate body in one embodiment of the present invention; Figure 7This is a schematic diagram of the first structure of the cover plate assembly in one embodiment of the present invention; Figure 8 This is a top view of a cover plate assembly according to an embodiment of the present invention; Figure 9 This is one embodiment of the present invention. Figure 8 AA section view; Figure 10 This is a schematic diagram of the second structure of the cover plate assembly in one embodiment of the present invention; Figure 11 This is a first exploded view of the cover plate assembly in one embodiment of the present invention; Figure 12 This is a second exploded view of the cover plate assembly in one embodiment of the present invention; Figure 13 This is a side view of a cover plate assembly according to an embodiment of the present invention; Figure 14 This is a bottom view of a cover plate assembly according to an embodiment of the present invention.

[0019] In the picture: 1. Pole assembly; 11. First assembly slot; 111. First part; 112. Second part; 12. Second assembly slot; 13. First electrode ear; 14. Second electrode ear; 15. Protrusion; 16. Inclined surface; 2. Cover plate assembly; 21. First cover plate body; 211. Snap-fit ​​part; 2111. First part; 2112. Second part; 212. Bending part; 213. Connecting part; 22. Second cover plate body; 23. Pole post; 231. Sealing ring; 24. First welding block; 25. Second welding block; 26. First plastic; 27. Second plastic; 3. Housing; 31. Step; 4. Explosion-proof valve; X, First direction; Y, Second direction; Z, Third direction. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0021] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0023] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0024] See Figures 1 to 5 This invention provides a battery comprising two electrode groups 1 arranged along a first direction X, a cover plate assembly 2, and a housing 3. A first mounting groove 11 is formed at the ends of the two electrode groups 1 that are far apart from each other, and a second mounting groove 12 is formed on the side of the ends of the two electrode groups 1 that are close to each other. Each electrode group 1 is provided with a first tab 13 and a second tab 14, the first tab 13 being disposed within the first mounting groove 11 and the second tab 14 being disposed within the second mounting groove 12. A protrusion 15 is formed on the surface of each electrode group 1 in the second direction Y. The cover plate assembly 2 includes a first cover plate body 21, a second cover plate body 22, and a plurality of terminal posts 23. The first cover plate body 21 is disposed corresponding to the first mounting groove 11, and the second cover plate body 22 is disposed corresponding to the second mounting groove 12. The first cover plate body 21 encloses... The assembly includes a snap-fit ​​portion 211, which snaps into the protrusion 15. The pole post 23, located in the first assembly groove 11, is electrically connected to the first pole tab 13. The pole post 23, located in the second assembly groove 12, is electrically connected to the second pole tab 14. Along the first direction X, the surface of the first cover plate body 21 facing away from the pole assembly 1 protrudes from the pole post 23. The pole assembly 1 is snap-fitted into the housing 3. The first cover plate body 21, the second cover plate body 22, and the housing 3 enclose a space for accommodating the pole assembly 1. Along the third direction Z, the surface of the housing 3 facing away from the pole assembly 1 protrudes from the pole post 23. The first direction X is the thickness direction of the first cover plate body 21, the second direction Y is the width direction of the first cover plate body 21, and the third direction Z is the length direction of the first cover plate body 21.

[0025] In this embodiment, conductive coatings are provided on the end faces of the electrode groups 1 that are close to each other, so that the two electrode groups 1 can be electrically connected. The first mounting grooves 11 of the two electrode groups 1 are provided on the same side of the electrode groups 1 in the first direction X. When the two electrode groups 1 are assembled, the second mounting grooves 12 corresponding to the two electrode groups 1 are connected and form a space for accommodating the second cover plate body 22 and the corresponding pole post 23. The first cover plate body 21 is provided with a one-to-one correspondence with the first pole tab 13. The second cover plate body 22 is provided with one pole post 23 connected to the second cover plate body 22 and the corresponding pole post 23 of the two electrode groups 1. The second tab 14 is connected to the first assembly groove 11 of the second assembly groove 12, which is integrally formed with the second assembly groove 1 to improve the battery capacity. The end of the second assembly groove 12 of the second assembly groove 12 is flush with the end face of the second assembly groove 1. The snap-fit ​​part 211 and the housing 3 are both fitted to the second assembly groove 14 so that the first cover plate body 21 and the housing 3 can fit to the second assembly groove 1. The first cover plate body 21 and the second cover plate body 22 are both sealed and fixedly connected to the housing 3 by welding.

[0026] See Figure 3 and Figure 6 The housing 3 is arranged in a one-to-one correspondence with the pole group 1. One of the housings 3 has a step 31 at the end facing the other housing 3, so as to quickly position the two housings 3 and improve the assembly effect.

[0027] Furthermore, in some embodiments, the battery also includes two explosion-proof valves 4, which are respectively disposed on both sides of the pole post 23 located in the second assembly groove 12.

[0028] Thus, the electrode post 23 is positioned within the first assembly slot 11 and the second assembly slot 12, which improves the protection of the electrode post 23, preventing it from being bumped or damaged during transportation and assembly processes, thereby enhancing battery safety. It also increases the space utilization between the electrode assembly 1 and the cover plate assembly 2, making the battery structure more compact. The protrusion 15 on the side of the electrode assembly 1 increases the battery capacity while simultaneously strengthening the connection between the electrode assembly 1 and the cover plate assembly 2 and the housing 3, preventing damage and movement of the electrode assembly 1 during installation, and facilitating the fulfillment of high-capacity, high-rate fast charging requirements.

[0029] It is understandable that the number and location of the explosion-proof valves 4 can be adjusted according to actual needs, which will not be elaborated here.

[0030] See Figure 3In some embodiments, the first mounting groove 11 includes a first part 111 and a second part 112. The first part 111 is disposed at the end of the electrode group 1 in the first direction X, and the second part 112 is disposed at the side of the electrode group 1 in the third direction Z. The first part 111 extends along the third direction Z, and the second part 112 extends along the first direction X. The first electrode tab 13 is disposed in the first part 111 and the second part 112.

[0031] In this embodiment, the first part 111 is connected to the second part 112. The first assembly groove 11 is an L-shaped groove, and the second assembly groove 12 is a straight groove. The first assembly groove 11 is located at the corner of the pole group 1.

[0032] In this way, the space at the end and side of the electrode assembly 1 can be fully utilized to set multiple pole posts 23, thereby improving the battery's overcurrent capacity and space utilization. Furthermore, the first cover plate body 21 and the housing 3 can improve the protection effect on the pole posts 23. The protrusion 15 is set on the side of the electrode assembly 1 in the second direction Y, which can improve the power while avoiding assembly interference with the cover plate assembly 2, making the battery structure more compact.

[0033] It is understood that the first assembly groove 11 can also be a straight groove. In this embodiment, the first assembly groove 11 is an L-shaped groove, which can increase the length of the first electrode 13 and thus improve the flow capacity. The shape and setting position of the first assembly groove 11 and the second assembly groove 12 can be adjusted according to actual needs, which will not be elaborated here.

[0034] See Figure 3 and Figure 7 In some embodiments, the end of the electrode group 1 is provided with an inclined surface 16, which is disposed on the side of the first mounting groove 11 in the third direction Z. The extension direction of the inclined surface 16 is obliquely intersecting the third direction Z. The width of the end of the electrode group 1 away from the other electrode group 1 is less than the width of the position where the first mounting groove 11 is opened. The snap-fit ​​part 211 includes a first part 2111 and a second part 2112. The inclination angle of the first part 2111 is equal to the inclination angle of the inclined surface 16. The second part 2112 is disposed on the side of the first part 2111 away from the first mounting groove 11.

[0035] In this embodiment, along the second direction Y, the inclined surface 16 extends to the protrusion 15, the end shape of the first assembly groove 11 of the pole group 1 is a right trapezoid, the first part 2111 and the second part 2112 are integrally formed, and the second part 2112 extends along the third direction Z.

[0036] This increases the assembly space at the first assembly slot 11, which is beneficial for assembling the cover plate assembly 2 and connecting the battery to the external circuit. The inclined surface 16 can guide the assembly of the first cover plate body 21, achieve rapid positioning, improve assembly efficiency, and enhance the connection strength between the electrode group 1 and the first cover plate body 21, preventing the first cover plate body 21 from shifting and improving battery safety.

[0037] See Figure 8 and Figure 9 In some embodiments, along the third direction Z, the length of the second part 2112 is L1, the length of the snap-fit ​​part 211 is L2, and the condition 0.7≤L1 / L2≤0.95 is satisfied. The angle between the inclined surface 16 and the end face of the pole group 1 that is away from the other pole group 1 is N, and the condition 100°≤N≤150° is satisfied.

[0038] In this embodiment, the ratio of the length L1 of the second part 2112 to the length L2 of the snap-fit ​​part 211 can be any value between 0.7 and 0.95 or any range between any two values, such as 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, etc.; the angle N between the inclined surface 16 and the end face of the pole group 1 that is away from the other pole group 1 (that is, the angle between the inclined surface 16 and the third direction Z) can be any value between 100° and 150° or any range between any two values, such as 100°, 120°, 130°, 150°, etc.

[0039] In this way, the first part 2111 and the second part 2112 can be fitted together at the end of the pole group 1, which improves the connection strength between the pole group 1 and the cover plate assembly 2, thereby improving the protection effect on the pole post 23 located in the first assembly groove 11, and improving the space utilization between the pole group 1 and the cover plate assembly 2, avoiding assembly interference between the first part 2111, the second part 2112 and the pole post 23, and improving the assembly effect.

[0040] Understandably, the ratio of the length L1 of the second part 2112 to the length L2 of the snap-fit ​​part 211 cannot be too small. If it is too small, the first part 2111 set on the corresponding inclined surface 16 will occupy too much space, which is not conducive to the improvement of power. The ratio of the length L1 of the second part 2112 to the length L2 of the snap-fit ​​part 211 cannot be too large either. If it is too large, it will reduce the space of the first part 2111, which is not conducive to positioning the first cover body 21 to the end of the pole group 1 and reducing assembly efficiency. The angle N between the inclined surface 16 and the end face of the pole group 1 that is away from the other pole group 1 cannot be too small. If it is too small, it will reduce assembly efficiency. The angle N between the inclined surface 16 and the end face of the pole group 1 that is away from the other pole group 1 cannot be too large either. If it is too large, it will affect the size of the pole group 1 and increase the processing difficulty.

[0041] See Figures 10 to 12In some embodiments, the cover plate assembly 2 further includes a first welding block 24 and a second welding block 25, wherein the first welding block 24 is opposite to the electrode assembly 1 from the electrode post 23 (see...). Figure 3 One end of the first cover plate 21 is connected to the first welding block 24 located in the first assembly groove 11, which is opposite to the surface of the electrode group 1. Along the third direction Z, the housing 3 is connected to the first welding block 24 located in the second assembly groove 12, which is opposite to the surface of the electrode group 1. The second welding block 25 is connected to the end of the pole post 23 facing the electrode group 1.

[0042] In this embodiment, the cover plate assembly 2 further includes a first plastic 26 and a second plastic 27. A first welding block 24 is disposed on the side of its corresponding first cover plate body 21 or second cover plate body 22 away from the electrode group 1, and a second welding block 25 is disposed on the side of its corresponding first cover plate body 21 or second cover plate body 22 facing the electrode group 1. The first plastic 26 is disposed between the first welding block 24 and its corresponding first cover plate body 21 or second cover plate body 22, and the second plastic 27 is disposed between the second welding block 25 and its corresponding first cover plate body 21 or second cover plate body 22 to improve the insulation performance of the cover plate assembly 2. The first welding block 24 and the second welding block 25 corresponding to the first assembly groove 11 are both L-shaped plate structures, and the surface of the first cover plate body 21 away from the electrode group 1 protrudes from the corresponding first welding block 24. The shape of the second plastic 27 corresponding to the first assembly groove 11 is adapted to the shape of the first cover plate body 21. A sealing ring 231 is sleeved on the electrode post 23 to improve the sealing performance of the cover plate assembly 2.

[0043] Thus, by setting the cover plate assembly 2 at the end and side of the electrode group 1, the overcurrent capacity of the battery can be improved and the battery structure can be made more compact. This is beneficial for the battery to be connected with other batteries or external circuits, increasing the battery packing rate and improving the structural strength of the cover plate assembly 2. This is beneficial for the stable connection between the cover plate assembly 2 and the electrode group 1, avoiding damage and movement of the electrode group 1 during the casing process, and improving the safety of the battery.

[0044] See Figure 9 In some embodiments, the thickness of the first welding block 24 is T1, and satisfies 2mm≤T1≤3.5mm, and the thickness of the second welding block 25 is T2, and satisfies 1.5mm≤T2≤3mm.

[0045] In this embodiment, the thickness T1 of the first welding block 24 can be any value between 2mm and 3.5mm or any range between any two values, such as 2mm, 2.5mm, 3mm, 3.5mm, etc.; the thickness T2 of the second welding block 25 can be any value between 1.5mm and 3mm or any range between any two values, such as 1.5mm, 2mm, 2.5mm, 3mm, etc.

[0046] This improves the structural strength of the cover plate assembly 2, ensures a stable connection between the cover plate assembly 2 and the electrode assembly 1, prevents damage and movement of the electrode assembly 1 when it is installed in the casing, reduces the risk of deformation of the electrode assembly 1 and the cover plate assembly 2 due to external forces, increases the current flow area, and improves the fast charging performance of the battery.

[0047] It is understandable that the thickness T1 of the first welding block 24 and the thickness T2 of the second welding block 25 cannot be too small. If they are too small, the structural strength of the cover plate assembly 2 will be reduced, and the connection stability between the electrode group 1 and the cover plate assembly 2 will be reduced. The thickness T1 of the first welding block 24 and the thickness T2 of the second welding block 25 cannot be too large either. If they are too large, the battery size will be increased, affecting the space utilization rate.

[0048] See Figure 3 and Figure 7 In some embodiments, the first cover plate body 21 includes a bending portion 212 and a connecting portion 213, the bending portion 212 and the connecting portion 213 are arranged at positions corresponding to the first mounting groove 11, and the bending portion 212 is connected to the snap-fit ​​portion 211.

[0049] In this embodiment, the shape of the bending portion 212 is adapted to the shape of the first assembly groove 11, and the connecting portion 213 is provided corresponding to the second part 112 groove wall of the first assembly groove 11. The connecting portion 213, the bending portion 212 and the snap-fit ​​portion 211 are integrally formed to cover the end of the electrode group 1 and snap-fit ​​with the electrode group 1.

[0050] In this way, the first cover plate body 21 can be fitted to the end of the electrode assembly 1, which improves the structural strength of the first cover plate body 21 and the connection strength with the electrode assembly 1, avoids damage and movement of the electrode assembly 1 during the casing process, and reduces the risk of the first cover plate body 21 being subjected to external forces and deforming, thereby improving the safety of the battery.

[0051] It is understandable that the shape of the first cover plate body 21 can be adjusted according to the shape of the end of the pole group 1, which will not be elaborated here.

[0052] See Figure 9 and Figure 13 In some embodiments, along the first direction X, the height of the bent portion 212 is H1, and satisfies 15mm≤H1≤80mm. Along the second direction Y, the first cover plate body 21 corresponds to pole group 1 (see...). Figure 3 The width of the position is B1, and the width of the first welding block 24 is F, and the conditions are met: 5mm≤B1-F≤16mm.

[0053] In this embodiment, the height H1 of the bent portion 212 can be any value between 15mm and 80mm or any two values, such as 15mm, 20mm, 40mm, 60mm, 80mm, etc. The difference between the width B1 of the first cover plate body 21 corresponding to the position of the pole group 1 and the width F of the first welding block 24 (that is, the length of the first cover plate body 21 protruding from the first welding block 24 on both sides) can be any value between 5mm and 16mm or any two values, such as 5mm, 10mm, 15mm, 16mm, etc.

[0054] Thus, the first cover plate body 21 has sufficient structural strength to support the first welding block 24 and is stably snapped into the electrode group 1, improving the connection stability between the cover plate assembly 2 and the electrode group 1, providing sufficient space at the end of the electrode group 1 to assemble the electrode post 23 and the first welding block 24, improving the protection effect on the electrode post 23 and the first welding block 24, avoiding bumps and damage, improving the space utilization of the battery, and making the battery structure more compact.

[0055] Understandably, the height H1 of the bending portion 212 cannot be too small, as this would reduce the space of the first assembly slot 11, affecting the assembly space of the cover plate assembly 2 and the current carrying capacity of the battery. The height H1 of the bending portion 212 cannot be too large either, as this would reduce the size of the electrode group 1 and affect the increase in power capacity. The difference between the width B1 of the first cover plate body 21 corresponding to the electrode group 1 and the width F of the first welding block 24 cannot be too small, as this would increase the risk of the first welding block 24 colliding with external structures. The difference between the width B1 of the first cover plate body 21 corresponding to the electrode group 1 and the width F of the first welding block 24 cannot be too large either, as this would result in insufficient size of the first welding block 24 and affect the current carrying capacity of the battery.

[0056] See Figure 9 In some embodiments, along the third direction Z, the length of the snap-fit ​​portion 211 is L2, the length of the first cover plate body 21 is A, and the condition 0.35≤L2 / A≤0.75 is satisfied. Along the first direction X, the height of the snap-fit ​​portion 211 is E, and the condition 12mm≤E≤40mm is satisfied.

[0057] In this embodiment, the ratio of the length L2 of the snap-fit ​​portion 211 to the length A of the first cover plate body 21 can be any value between 0.35 and 0.75 or any range between any two values, such as 0.35, 0.45, 0.55, 0.65, 0.75, etc., and the height E of the snap-fit ​​portion 211 can be any value between 12mm and 40mm or any range between any two values, such as 12mm, 20mm, 30mm, 40mm, etc.

[0058] In this way, the snap-fit ​​part 211 can be stably snapped into the protrusion 15, which improves the connection strength between the electrode assembly 1 and the first cover plate body 21 as well as the structural strength of the first cover plate body 21, avoids damage and movement of the electrode assembly 1 during the process of inserting it into the casing, and makes full use of the space of the electrode assembly 1 in the second direction Y to set the protrusion 15, thereby increasing the battery capacity while maintaining a compact battery structure.

[0059] Understandably, the ratio of the length L2 of the latching part 211 to the length A of the first cover body 21 cannot be too small, otherwise the size of the latching part 211 will be reduced, which is not conducive to the improvement of power. The ratio of the length L2 of the latching part 211 to the length A of the first cover body 21 cannot be too large, otherwise it will encroach on the space of the first assembly slot 11, which is not conducive to the assembly of the cover assembly 2. The height E of the latching part 211 cannot be too small, otherwise it will affect the connection stability between the first cover body 21 and the electrode group 1. The height E of the latching part 211 cannot be too large, otherwise it will increase the battery size and affect the space utilization rate.

[0060] See Figure 8 and Figure 14 In some embodiments, along the third direction Z, the first cover plate body 21 corresponds to the protrusion 15 (see...). Figure 3 The length of the first cover plate body 21 is L3, and the length of the first cover plate body 21 is A, satisfying 0.25≤L3 / A≤0.7. Along the second direction Y, the width of the first cover plate body 21 corresponding to the protrusion 15 is B2, and the width of the first cover plate body 21 corresponding to the pole group 1 (that is, the width of the part of the first cover plate body 21 not connected to the protrusion 15) is B1, satisfying 10mm≤B2-B1≤70mm.

[0061] In this embodiment, the ratio of the length L3 of the first cover plate body 21 corresponding to the protrusion 15 to the length A of the first cover plate body 21 can be any value between 0.25 and 0.7, or any range between any two values, such as 0.25, 0.3, 0.5, 0.7, etc.; the difference between the width B2 of the first cover plate body 21 corresponding to the protrusion 15 and the width B1 of the first cover plate body 21 corresponding to the electrode group 1 can be any value between 10mm and 70mm, or any range between any two values, such as 10mm, 30mm, 50mm, 70mm, etc. In this way, the side space of the electrode group 1 can be fully utilized to set the protrusion 15, improving space utilization. The protrusion 15 not only increases the battery's capacity but also allows the electrode group 1 to be stably engaged with the first cover plate body 21 and the housing 3, limiting the relative positions of the three, improving the assembly effect, preventing the electrode group 1 from shifting or moving within the housing 3, and improving the battery's stability.

[0062] Understandably, the ratio of the length L3 of the first cover plate body 21 corresponding to the protrusion 15 to the length A of the first cover plate body 21 cannot be too small. If it is too small, the size of the protrusion 15 will be reduced, which is not conducive to the improvement of power. The ratio of the length L3 of the first cover plate body 21 corresponding to the protrusion 15 to the length A of the first cover plate body 21 cannot be too large either. If it is too large, the battery size will increase, and the molding difficulty and cost of the cover plate assembly 2 and the shell 3 will increase. The difference between the width B2 of the first cover plate body 21 corresponding to the protrusion 15 and the width B1 of the first cover plate body 21 corresponding to the electrode group 1 cannot be too small. If it is too small, it will affect the improvement of power. The difference between the width B2 of the first cover plate body 21 corresponding to the protrusion 15 and the width B1 of the first cover plate body 21 corresponding to the electrode group 1 cannot be too large either. If it is too large, the battery size will be larger and occupy more space.

[0063] To verify the rationality of the ratio of the length L2 of the snap-fit ​​portion 211 to the length A of the first cover plate body 21, the ratio of the length L1 of the second portion 2112 to the length L2 of the snap-fit ​​portion 211, the height H1 of the bent portion 212, the width B1 of the first cover plate body 21 corresponding to the position of pole group 1 and the width F of the first welding block 24, the height E of the snap-fit ​​portion 211, the ratio of the length L3 of the first cover plate body 21 corresponding to the position of the protrusion 15 to the length A of the first cover plate body 21, the difference between the width B2 of the first cover plate body 21 corresponding to the position of the protrusion 15 and the width B1 of the first cover plate body 21 corresponding to the position of pole group 1, the angle N between the inclined surface 16 and the end face of the pole group 1 facing away from the other pole group 1, the thickness T1 of the first welding block 24, and the thickness T2 of the second welding block 25, as shown in Table 1, this embodiment provides six sets of embodiments and six sets of comparative examples for illustration.

[0064] Table 1 As shown in Examples 1 to 6 of Table 1, after meeting the range limitations, the battery yield meets the requirements, and no abnormalities such as positioning deviations or low structural strength are observed in the cover assembly 2, housing 3, etc. The cover assembly 2, electrode group 1, and electrode tabs are all undamaged and undeformed. The current carrying capacity and temperature of the cover assembly 2 meet the battery requirements.

[0065] As can be seen from Comparative Example 1, when the ratio of the length L2 of the snap-fit ​​part 211 to the length A of the first cover plate body 21 is too small, the battery yield does not meet the requirements, and the length ratio of the protrusion 15 is insufficient, which affects the increase in battery capacity.

[0066] As can be seen from Comparative Example 2, when the ratio of the length L2 of the snap-fit ​​part 211 to the length A of the first cover plate body 21 is too large, the battery yield does not meet the requirements. The length of the protrusion 15 is too large, occupying the space of the cover plate assembly 2 and affecting the structural strength and current carrying capacity of the cover plate assembly 2.

[0067] As can be seen from Comparative Example 3, when the height H1 of the bending part 212 is too small, the battery yield does not meet the requirements. The insufficient height of the bending part 212 reduces the weldable area of ​​the first welding block 24, affecting the battery's overcurrent capacity and failing to meet the fast charging requirements.

[0068] As can be seen from Comparative Example 4, when the height H1 of the bending part 212 is too large, the battery yield does not meet the requirements. The excessive height of the bending part 212 increases the weight of the cover assembly 2 and the cost of processing and forming, while reducing the welding efficiency of the shell and cover.

[0069] As can be seen from Comparative Example 5, when the ratio of the length L3 of the first cover plate body 21 corresponding to the protrusion 15 position to the length A of the first cover plate body 21 is too small, the battery yield does not meet the requirements, the volume ratio of the protrusion 15 is insufficient, the overall size of the electrode group 1 is reduced, and the increase in battery capacity is affected.

[0070] As can be seen from Comparative Example 6, when the ratio of the length L3 of the first cover plate body 21 corresponding to the protrusion 15 position to the length A of the first cover plate body 21 is too large, the battery yield does not meet the requirements. The volume ratio of the protrusion 15 is too large, which increases the stamping difficulty and cost of the cover plate assembly 2 and the shell 3.

[0071] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A battery, characterized in that, include: Two pole groups (1) are arranged along a first direction (X). The ends of the two pole groups (1) that are far apart from each other are provided with a first mounting groove (11). The sides of the ends of the two pole groups (1) that are close to each other are provided with a second mounting groove (12). The pole group (1) is provided with a first electrode tab (13) and a second electrode tab (14). The first electrode tab (13) is provided in the first mounting groove (11). The second electrode tab (14) is provided in the second mounting groove (12). The surface of the pole group (1) in the second direction (Y) is provided with a protrusion (15). Cover plate assembly (2), the cover plate assembly (2) includes a first cover plate body (21), a second cover plate body (22) and a plurality of pole posts (23), the first cover plate body (21) is disposed corresponding to the first assembly groove (11), the second cover plate body (22) is disposed corresponding to the second assembly groove (12), the first cover plate body (21) includes a snap-fit ​​part (211), the snap-fit ​​part (211) is snap-fitted with the protrusion (15), the pole post (23) disposed in the first assembly groove (11) is electrically connected to the first electrode ear (13), the pole post (23) disposed in the second assembly groove (12) is electrically connected to the second electrode ear (14), along the first direction (X), the surface of the first cover plate body (21) facing away from the pole group (1) protrudes from the pole post (23); The housing (3) is snapped into the electrode assembly (1). The first cover plate body (21), the second cover plate body (22) and the housing (3) enclose a space for accommodating the electrode assembly (1). Along the third direction (Z), the surface of the housing (3) facing away from the electrode assembly (1) protrudes from the pole post (23). The first direction (X) is the thickness direction of the first cover plate body (21), the second direction (Y) is the width direction of the first cover plate body (21), and the third direction (Z) is the length direction of the first cover plate body (21).

2. The battery according to claim 1, characterized in that, The first assembly groove (11) includes a first part (111) and a second part (112). The first part (111) is disposed at the end of the pole group (1) in the first direction (X), and the second part (112) is disposed at the side of the pole group (1) in the third direction (Z). The first part (111) extends along the third direction (Z), and the second part (112) extends along the first direction (X). The first electrode tab (13) is disposed in the first part (111) and the second part (112).

3. The battery according to claim 1, characterized in that, The end of the pole group (1) is provided with an inclined surface (16), which is located on one side of the first assembly groove (11) in the third direction (Z). The extension direction of the inclined surface (16) is obliquely intersecting the third direction (Z). The width of the end of the pole group (1) away from the other pole group (1) is smaller than the width of the position where the first assembly groove (11) is opened. The snap-fit ​​part (211) includes a first part (2111) and a second part (2112). The inclination angle of the first part (2111) is equal to the inclination angle of the inclined surface (16). The second part (2112) is located on the side of the first part (2111) away from the first assembly groove (11).

4. The battery according to claim 3, characterized in that, Along the third direction (Z), the length of the second part (2112) is L1, the length of the snap-fit ​​part (211) is L2, and the condition 0.7≤L1 / L2≤0.95 is satisfied; and / or, the angle between the inclined surface (16) and the end face of the pole group (1) facing away from the other pole group (1) is N, and the condition 100°≤N≤150° is satisfied.

5. The battery according to claim 1, characterized in that, The cover plate assembly (2) further includes a first welding block (24) and a second welding block (25). The first welding block (24) is connected to the end of the pole post (23) away from the pole group (1). Along the first direction (X), the surface of the first cover plate body (21) away from the pole group (1) protrudes from the first welding block (24) located in the first assembly groove (11). Along the third direction (Z), the surface of the housing (3) away from the pole group (1) protrudes from the first welding block (24) located in the second assembly groove (12). The second welding block (25) is connected to the end of the pole post (23) facing the pole group (1).

6. The battery according to claim 5, characterized in that, The thickness of the first welding block (24) is T1, and satisfies 2mm≤T1≤3.5mm; and / or the thickness of the second welding block (25) is T2, and satisfies 1.5mm≤T2≤3mm.

7. The battery according to claim 5, characterized in that, The first cover plate body (21) includes a bending part (212) and a connecting part (213). The bending part (212) and the connecting part (213) are arranged corresponding to the position of the first assembly groove (11). The bending part (212) is connected to the snap-fit ​​part (211).

8. The battery according to claim 7, characterized in that, Along the first direction (X), the height of the bent portion (212) is H1, and satisfies 15mm≤H1≤80mm; and / or, along the second direction (Y), the width of the first cover plate body (21) corresponding to the position of the pole group (1) is B1, and the width of the first welding block (24) is F, and satisfies 5mm≤B1-F≤16mm.

9. The battery according to any one of claims 1-8, characterized in that, Along the third direction (Z), the length of the snap-fit ​​portion (211) is L2, the length of the first cover plate body (21) is A, and 0.35≤L2 / A≤0.75; and / or, along the first direction (X), the height of the snap-fit ​​portion (211) is E, and 12mm≤E≤40mm.

10. The battery according to any one of claims 1-8, characterized in that, Along the third direction (Z), the length of the first cover plate body (21) corresponding to the position of the protrusion (15) is L3, the length of the first cover plate body (21) is A, and satisfies 0.25≤L3 / A≤0.7; and / or, along the second direction (Y), the width of the first cover plate body (21) corresponding to the position of the protrusion (15) is B2, the width of the first cover plate body (21) corresponding to the position of the pole group (1) is B1, and satisfies 10mm≤B2-B1≤70mm.

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