Battery cell and electric device

Abstract

The utility model discloses a kind of battery monomer and electric device, it belongs to battery technical field, battery monomer includes shell, battery cell component and battery top cover, at least one end of shell forms opening;Battery cell component is set in shell, battery cell component has tab;Battery top cover includes cover plate and pole, cover plate closes the opening of shell, pole is set on cover plate, pole includes the first connecting part and at least two second connecting parts distributed along first direction, second connecting part is used to be connected with tab to make third welding area on tab, along first direction, the spacing of third welding area and the edge of cover plate is d1, 3mm≤d1≤15mm, so that third welding area on tab is away from the edge of cover plate, can be smoothly connected with pole and avoid pole distance The edge of cover plate is too close, guarantee the structural strength of cover plate, and avoid affecting subsequent processing procedure after injection molding.Electric device includes above-mentioned battery monomer.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery cell and an electrical device. Background Technology

[0002] The battery cell in the related technology includes a battery top cover, which includes a cover plate and a terminal post. The cover plate has a through hole, and the terminal post adopts a bridge-type terminal post structure. The terminal post includes a first connecting part and two second connecting parts distributed on both sides of the first connecting part. The second connecting parts pass through the through hole and are connected to the electrode tab, so as to realize the direct connection between the terminal post and the electrode tab.

[0003] For battery cells with edge-mounted tabs, the tabs are located at the edge of the cell. To reduce the height of the tabs, the welding area between the tabs and the terminal post is close to the edge of the cover plate, resulting in the through-hole being close to the edge of the cover plate, which reduces the structural strength of the cover plate. After injection molding, the injection molded part is too close to the edge, affecting subsequent laser welding and blue film coating processes. Utility Model Content

[0004] This utility model provides a battery cell and an electrical device to solve the technical problem in the prior art where the welding area between the tab and the terminal post is close to the edge of the cover plate.

[0005] Based on the above concept, the technical solution adopted by this utility model is as follows:

[0006] A single battery cell, comprising:

[0007] The outer shell has an opening at at least one end;

[0008] A battery cell assembly is disposed within the housing, and the battery cell assembly has tabs;

[0009] A battery top cover includes a cover plate and a terminal post. The cover plate closes the opening of the outer casing. The terminal post is disposed on the cover plate. The terminal post includes a first connecting portion distributed along a first direction and at least two second connecting portions. The second connecting portions are used to connect with the tabs to form a third welding area on the tabs. Along the first direction, the distance between the third welding area and the edge of the cover plate is d1, where 3mm≤d1≤15mm.

[0010] Preferably, the pole also includes a fixing member, which includes a first connecting area and a second connecting area, wherein the first connecting area is connected to the second connecting part, and the second connecting area is connected to the third welding area.

[0011] Preferably, along the first direction, the distance between the edge of the fastener and the edge of the cover plate is f, where 1mm≤f≤10mm.

[0012] Preferably, the tab includes a bent portion and an extension portion, the extension portion being located on one side of the fastener along a second direction, and on a dummy plane perpendicular to the second direction, at least a portion of the orthographic projection of the extension portion is located outside the orthographic projection of the second connecting portion, wherein the first direction intersects the second direction.

[0013] Preferably, on the dummy plane, the projection of the fastener overlaps the projection of the extension.

[0014] Preferably, along the first direction, the width of the cover plate is b, and the minimum width of the extension is g, wherein 4% ≤ g / b ≤ 30%.

[0015] Preferably, the second connecting portion includes a first metal layer and a second metal layer, the second metal layer being located on the side of the first metal layer near the fixing member, the first connecting portion including the first metal layer, and the second metal layer being connected to the fixing member.

[0016] Preferably, a first insulating element is provided between the pole and the cover plate, and the distance between the edge of the first insulating element and the edge of the cover plate along the first direction is a, wherein 4mm≤a≤20mm.

[0017] Preferably, along the first direction, the width of the second connection portion is c, and the width of the pole post is e, wherein 8% ≤ c / e ≤ 35%.

[0018] An electrical device comprising a battery cell as described above.

[0019] The beneficial effects of this utility model are:

[0020] The battery cell proposed in this utility model includes a casing, a cell assembly, and a battery top cover. At least one end of the casing forms an opening, and the cell assembly is disposed inside the casing. The cell assembly has tabs. The battery top cover includes a cover plate and a terminal post. The cover plate closes the opening of the casing, and the terminal post is disposed on the cover plate. The terminal post includes a first connecting portion distributed along a first direction and at least two second connecting portions. The second connecting portions are used to connect with the tabs to form a third welding area on the tabs. Along the first direction, the distance between the third welding area and the edge of the cover plate is 3mm-15mm. This ensures that the third welding area on the tabs is far from the edge of the cover plate, allowing for smooth connection with the terminal post and preventing the terminal post from being too close to the edge of the cover plate, thus ensuring the structural strength of the cover plate and preventing it from affecting subsequent processing steps after injection molding. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of a battery cell provided in an embodiment of this utility model;

[0022] Figure 2This is an exploded structural diagram of a battery cell provided in an embodiment of the present invention;

[0023] Figure 3 This is an exploded structural diagram of the battery top cover provided in an embodiment of the present invention;

[0024] Figure 4 This is a schematic diagram of the first structure of the pole provided in this embodiment of the utility model;

[0025] Figure 5 This is a schematic diagram of the second structure of the pole provided in an embodiment of the present invention;

[0026] Figure 6 This is a top view of a battery cell provided in an embodiment of the present utility model;

[0027] Figure 7 yes Figure 6 Sectional view along axis AA;

[0028] Figure 8 This is a first cross-sectional view of a partial structure of a battery cell provided in an embodiment of the present invention;

[0029] Figure 9 This is a second cross-sectional view of a partial structure of a battery cell provided in an embodiment of the present invention;

[0030] Figure 10 This is a cross-sectional view of another battery cell provided in an embodiment of this utility model;

[0031] Figure 11 This is a first cross-sectional view of a partial structure of another battery cell provided in this embodiment of the present invention;

[0032] Figure 12 This is a second cross-sectional view of a partial structure of another battery cell provided in this embodiment of the present invention;

[0033] Figure 13 This is a cross-sectional view of another battery cell provided in this embodiment of the present invention;

[0034] Figure 14 This is a first cross-sectional view of a partial structure of another battery cell provided in this embodiment of the present invention;

[0035] Figure 15 This is a second cross-sectional view of a partial structure of another battery cell provided in this embodiment of the present invention;

[0036] Figure 16 This is an exploded structural diagram of the battery pack provided in an embodiment of the present invention;

[0037] Figure 17 This is a schematic diagram of the electrical device provided in an embodiment of the present utility model.

[0038] In the picture:

[0039] 10. Outer shell; 11. Receiving cavity;

[0040] 20. Battery cell assembly; 21. Electrode tab; 211. Bending section; 212. Extension section;

[0041] 30. Battery top cover;

[0042] 31. Cover plate; 311. First through hole;

[0043] 32. Pole post; 321. First connecting part; 322. Second connecting part; 3221. First metal layer; 3222. Second metal layer; 323. Fastener; 324. Flanged edge;

[0044] 33. Sealing components;

[0045] 34. First insulating component;

[0046] 35. Second insulating component;

[0047] 100. Battery pack; 110. Battery housing; 120. Individual battery cell. Detailed Implementation

[0048] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0049] In the description of this utility model, 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 utility model based on the specific circumstances.

[0050] 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.

[0051] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0052] See Figures 1 to 9 This embodiment provides a battery cell 120, which includes a housing 10, a cell assembly 20, and a battery top cover 30. The housing 10 has an opening at at least one end. The cell assembly 20 is disposed within the housing 10 and has tabs 21. The battery top cover 30 is disposed on the housing 10 and connected to the tabs 21. Exemplarily, the housing 10 has a receiving cavity 11 with an opening at one end. The cell assembly 20 is disposed within the receiving cavity 11, and the end of the cell assembly 20 with the tabs 21 faces the opening. The battery top cover 30 includes a cover plate 31 and terminal posts 32. The cover plate 31 closes the opening of the housing 10, specifically by embedding the cover plate 31 within the housing 10. The terminal posts 32 are disposed on the cover plate 31 and connected to the tabs 21.

[0053] In some embodiments, the pole post 32 includes a first connecting portion 321 and at least two second connecting portions 322. The first connecting portion 321 and the second connecting portions 322 are arranged along a first direction. The first connecting portion 321 is located on one side of the cover plate 31 along a second direction, and the electrode tab 21 is located on the other side of the cover plate 31 along the second direction. The second connecting portions 322 are used to connect with the electrode tab 21 to form a third welding area on the electrode tab 21. The first direction intersects the second direction. Preferably, the first direction is perpendicular to the second direction. In this embodiment, X represents the first direction, Z represents the second direction, and Y represents the third direction. The first direction, the second direction, and the third direction are perpendicular to each other.

[0054] Along the first direction, the distance between the third welding area and the edge of the cover plate 31 is d1, where 3mm≤d1≤15mm. This ensures that the third welding area on the tab 21 is far from the edge of the cover plate 31, allowing for smooth connection with the pole post 32 while preventing the pole post 32 from being too close to the edge of the cover plate 31. This guarantees the structural strength of the cover plate 31 and avoids affecting subsequent processing steps after injection molding.

[0055] The second connecting portion 322 can be directly connected to the electrode tab 21 or indirectly connected to it. Exemplarily, the electrode post 32 also includes a fixing member 323, which connects the second connecting portion 322 to the electrode tab 21. The fixing member 323 includes a first connecting area and a second connecting area; the first connecting area is connected to the second connecting portion 322, and the second connecting area is connected to a third welding area. That is, when the fixing member 323 is provided, the third welding area of ​​the electrode tab 21 is connected to the fixing member 323.

[0056] The fastener 323 has a first welding area, which is connected to the third welding area of ​​the tab 21. The second connecting portion 322 has a second welding area, which is connected to the fourth welding area of ​​the fastener 323. The first and fourth welding areas on the fastener 323 can be spaced apart or overlap each other. For example, the first and fourth welding areas on the fastener 323 are spaced apart along a first direction, so that the second connecting portion 322 is away from the tab 21. For example, the first and fourth welding areas on the fastener 323 overlap each other, so that the tab 21, the fastener 323, and the second connecting portion 322 are welded together, increasing structural strength.

[0057] like Figure 8 As shown, the distance between the third welding area and the edge of the cover plate 31 is d1, where 3mm ≤ d1 ≤ 15mm. If d1 is less than 3mm, the electrode lug 21 is close to the edge of the cover plate 31, and the electrode post 32 is too close to the edge of the cover plate 31, resulting in low structural strength of the cover plate 31. If d1 is greater than 15mm, the electrode lug 21 is far from the edge of the cover plate 31, the length of the electrode lug 21 is large, the cost is high, and it occupies a large space. In some embodiments, 5mm ≤ d1 ≤ 10mm. In some embodiments, the distance d1 between the third welding area and the edge of the cover plate 31 is 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, or 15mm.

[0058] For example, the cover plate 31 is provided with a first through hole 311, which extends along the second direction and penetrates the cover plate 31; the pole post 32 includes a first connecting part 321, at least two second connecting parts 322 and a fixing member 323, the first connecting part 321 and the second connecting parts 322 are arranged along the first direction, the first connecting part 321 is located on one side of the cover plate 31 along the second direction, at least a portion of the second connecting parts 322 passes through the first through hole 311, at least a portion of the fixing member 323 is located on the other side of the cover plate 31 along the second direction and is connected to the second connecting part 322, the first welding area on the fixing member 323 for connecting with the pole tab 21 and the second welding area on the second connecting part 322 for connecting with the fixing member 323 both extend along the first direction.

[0059] By setting a fastener 323, the second connecting part 322 is connected to the tab 21, and the first welding area on the fastener 323 and the second welding area on the second connecting part 322 extend along the first direction. For the tab 21 with a small height, the second connecting part 322 can be far away from the edge of the cover plate 31, and thus the first through hole 311 is far away from the edge of the cover plate 31, ensuring the structural strength of the cover plate 31. After injection molding, the injection molded part is far away from the edge of the cover plate 31 to prevent it from affecting subsequent processing steps.

[0060] Meanwhile, the projection of the fixing member 323 along the second direction covers the first through hole 311, which can fix the pole post 32 on the cover plate 31 and prevent the pole post 32 from moving away from the receiving cavity 11. Furthermore, the projections of the first connecting portion 321 and the second connecting portion 322 along the second direction cover the first through hole 311, preventing the pole post 32 from moving closer to the receiving cavity 11. It should be noted that the first connecting portion 321 and the second connecting portion 322 are integrally formed, and the entire structure of the first connecting portion 321 and the second connecting portion 322 covers the first through hole 311 along the second direction. Preferably, the projection of the second connecting portion 322 along the second direction covers the projection of the first through hole 311, and the projection of the first connecting portion 321 along the second direction overlaps with the cover plate 31. The first connecting part 321, the second connecting part 322 and the fixing part 323 are located on both sides of the cover plate 311, and their projections along the second direction cover the projection of the first through hole 311, preventing the pole post 32 from moving along the second direction and ensuring the assembly stability of the pole post 32.

[0061] Along the first direction, the distance between the edge of the fastener 323 and the edge of the cover plate 31 is f, where 1mm ≤ f ≤ 10mm, thereby reducing the length of the electrode tab 21 along the first direction to prevent the edge of the electrode tab 21 from bending. If f is less than 1mm, it is easy to contact the edge of the housing 10 or the cover plate 311, causing a short circuit. If f is greater than 10mm, it will not serve the function of the adapter electrode tab 21. For example, 3mm ≤ f ≤ 8mm. For example, the distance f between the edge of the fastener 323 and the edge of the cover plate 31 is 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, or 10mm.

[0062] In some embodiments, the thickness of the battery cell assembly 20 along the first direction is b, where b ≥ 40 mm. If b is less than 40 mm, the battery cell assembly 20 is small, resulting in lower energy density and failing to meet the requirement of high space utilization. For example, 40 mm ≤ b ≤ 100 mm. If the thickness of the battery cell assembly 20 is greater than 100 mm, heat dissipation of the battery cell assembly 20 becomes more difficult. For example, 50 mm ≤ b ≤ 80 mm. The width of the cover plate 31 along the first direction is equal to the thickness of the battery cell assembly 20 along the first direction, therefore the width of the cover plate 31 along the first direction is b, where b ≥ 40 mm. For example, 40 mm ≤ b ≤ 100 mm; for example, 50 mm ≤ b ≤ 80 mm. For example, the width of the cover plate 31 along the first direction is 40 mm, 50 mm, 60 mm, 70 mm, 80 mm, 90 mm, or 100 mm.

[0063] The fastener 323 is welded to the pole post 32, specifically by laser welding. In some embodiments, such as... Figure 9 As shown, a through hole is provided on the fixing member 323, and the second connecting part 322 passes through the through hole. The edge of the second connecting part 322 and the edge of the through hole are laser welded. The fixing member 323 is welded to the electrode lug 21, which can be laser welding or ultrasonic welding.

[0064] In some embodiments, such as Figures 10 to 12 As shown, the fastener 323 and the pole post 32 are connected by through-weld, where the electric arc or heat source can completely melt through the workpiece during welding. The fastener 323 is located at the bottom of the second connecting part 322, and the fastener 323 and the second connecting part 322 are welded through each other, achieving full fusion of the weld in the thickness direction and preventing leakage. By placing the fastener 323 at the bottom of the second connecting part 322, the height of the pole post 32 in the second direction can be reduced, thereby reducing stamping difficulty and production costs. The fastener 323 and the tab 21 can also be connected by through-weld to increase structural strength.

[0065] Each cover plate 31 may be provided with one, two or more pole posts 32, and each pole post 32 shall have two or more first through holes 311, with each first through hole 311 corresponding to a second connecting portion 322. In some embodiments, the pole post 32 includes one first connecting portion 321 and two second connecting portions 322, with the two second connecting portions 322 distributed along a first direction on both sides of the first connecting portion 321. In some embodiments, the pole post 32 includes two first connecting portions 321 and three second connecting portions 322, with a first connecting portion 321 disposed between two adjacent second connecting portions 322.

[0066] For example, each cover plate 31 is provided with two pole posts 32, and two first through holes 311 are formed for each pole post 32. The two pole posts 32 are arranged at intervals along a third direction, and the two first through holes 311 formed for each pole post 32 are arranged at intervals along a first direction. The first connecting part 321 is located on the side of the cover plate 31 away from the cell assembly 20 along a second direction, and the fixing member 323 is located on the side of the cover plate 31 close to the cell assembly 20 along the second direction. The first direction, the third direction, and the second direction are perpendicular to each other.

[0067] A flange 324 is provided on the side of the second connecting portion 322 away from the fixing member 323. The flange 324 extends around the edge of the second connecting portion 322, and at least part of the flange 324 extends beyond the edge of the first through hole 311. The flange 324 acts as a limit for the second connecting portion 322. The flange 324 cooperates with the fixing member 323 to limit the second connecting portion 322 on both sides along the second direction, so that the pole post 32 and the cover plate 31 are firmly connected.

[0068] The battery top cover 30 also includes a seal 33, which is located between the fixing member 323 and the cover plate 31. The fixing member 323 presses against the seal 33, making the seal 33 stable and providing a seal to prevent electrolyte leakage. On a dummy plane perpendicular to the second direction, the orthographic projection of the fixing member 323 overlaps the orthographic projection of the first through hole 311, so that the fixing member 323 and the seal 33 are in full contact, resulting in better positioning of the seal 33.

[0069] Along the first direction, the width of the fastener 323 is d2, where 8mm ≤ d2 ≤ 30mm. This allows the fastener 323 to effectively hold the seal 33, saving material and facilitating welding between the fastener 323 and the tab 21. For example, 10mm ≤ d2 ≤ 20mm. For example, the width d2 of the fastener 323 along the first direction is 8mm, 10mm, 12mm, 15mm, 18mm, 20mm, 22mm, 25mm, 28mm, or 30mm.

[0070] In some embodiments, at least a portion of the seal 33 extends into the first through hole 311. Under the pressure of the fixing member 323, the seal 33 undergoes elastic deformation, filling the gap of the first through hole 311 and ensuring a better sealing effect.

[0071] The battery top cover 30 also includes a first insulating member 34, which is located between the terminal post 32 and the cover plate 31, serving as insulation and sealing. At least a portion of the edge of the first insulating member 34 is located between the flange 324 and the cover plate 31. The battery top cover 30 also includes a second insulating member 35, which is located between the cover plate 31 and the fixing member 323. A sealing member 33 is embedded in the second insulating member 35, and the sealing member 33 cooperates with the second insulating member 35 to enhance the insulation and sealing effect.

[0072] Along the first direction, the distance between the edge of the first insulating member 34 and the edge of the cover plate 31 is 'a', where a ≥ 4 mm. Increasing the distance between the edges of the first insulating member 34 and the cover plate 31 prevents the first insulating member 34 from melting and failing during welding of the cover plate 31 to the outer casing 10, and also increases the structural strength of the battery top cover 30. To ensure that the terminal post 32 has sufficient current-carrying area, 'a' cannot be too large. For example, 4 mm ≤ a ≤ 20 mm. For example, 6 mm ≤ a ≤ 15 mm. For example, along the first direction, the distance 'a' between the edge of the first insulating member 34 and the edge of the cover plate 31 is 4 mm, 6 mm, 8 mm, 10 mm, 12 mm, 15 mm, 18 mm, or 20 mm.

[0073] In some embodiments, such as Figures 13 to 15 As shown, the seal 33 is located between the cover plate 31 and the flange 324. The flange 324 presses against the seal 33, ensuring its stable position and providing a seal to prevent electrolyte leakage. The battery top cover 30 also includes a first insulating member 34, located between the flange 324 and the cover plate 31. The seal 33 is embedded in the first insulating member 34, and the seal 33 cooperates with the first insulating member 34 to enhance insulation and sealing. The battery top cover 30 also includes a second insulating member 35, located between the cover plate 31 and the fixing member 323.

[0074] The second connecting portion 322 includes a first metal layer 3221 and a second metal layer 3222. The second metal layer 3222 is located on the side of the first metal layer 3221 near the fixing member 323. The first connecting portion 321 includes the first metal layer 3221, and the second metal layer 3222 is connected to the fixing member 323. By setting the second connecting portion 322 as a composite structure, it is convenient to set the two metal layers to different materials according to requirements, thereby reducing costs. For example, the second metal layer 3222 is made of copper, and the first metal layer 3221 is made of aluminum, eliminating the need to make the entire pole post 32 made of copper, thus reducing costs. The fixing member 323 and the electrode tab 21 can be made of copper. When the fixing member 323 is welded to the second metal layer 3222 and the electrode tab 21, the same material is welded, which facilitates processing. It should be noted that the cost of copper is much higher than that of aluminum. By setting the second connecting portion 322 as a copper-aluminum composite structure, the cost of the pole post 32 can be reduced.

[0075] The first metal layer 3221 of the first connecting portion 321 and the first metal layer 3221 of the second connecting portion 322 can be integrally formed, facilitating processing and production. Along the first direction, the width of the second connecting portion 322 is c, where 4mm ≤ c ≤ 14mm. If c is greater than 14mm, the second connecting portion 322 is too large, increasing material costs; if c is less than 4mm, the flow capacity of the second connecting portion 322 cannot be guaranteed. For example, 6mm ≤ c ≤ 12mm. For example, the width of the second metal layer 3222 is equal to the width of the second connecting portion 322. For example, along the first direction, the width c of the second connecting portion 322 is 4mm, 6mm, 8mm, 10mm, 12mm, or 14mm.

[0076] Along the first direction, the width of the pole post 32 is e, where 20mm ≤ e ≤ 60mm. Specifically, 8% ≤ c / e ≤ 35%. If c / e is less than 8%, the width of the second connection portion 322 is too small, restricting the current flow of the entire pole post 32. If c / e is greater than 35%, the width of the second connection portion 322 is too large, resulting in excessive cost. Preferably, 15% ≤ c / e ≤ 20%.

[0077] In some embodiments, the tab 21 has a third welding area for connection with the fastener 323. The third welding area is located on the side of the fastener 323 away from the first connection portion 321 along the first direction. On a dummy plane perpendicular to the second direction, at least part of the orthographic projection of the third welding area is outside the orthographic projection of the first through hole 311, so that the tab 21 is away from the first through hole 311, and the first through hole 311 is away from the edge of the cover plate 31, thus ensuring the structural strength of the cover plate 31.

[0078] At least part of the orthographic projection of the third welding area is located within the orthographic projection of the first through hole 311, so that the electrode 21 can be located on the lower side of the second connecting part 322. The electrode 21, the fastener 323 and the second connecting part 322 are welded to improve the structural strength.

[0079] In some embodiments, the tab 21 includes a bent portion 211 and an extension portion 212. The extension portion 212 is located on one side of the fixing member 323 along a second direction. On a dummy plane perpendicular to the second direction, at least a portion of the orthographic projection of the extension portion 212 is located outside the orthographic projection of the second connecting portion 322. This causes the tab 21 to be away from the second connecting portion 322, and consequently, the first through hole 311 to be away from the edge of the cover plate 31, ensuring the structural strength of the cover plate 31. One end of the bent portion 211 is connected to the cell body of the cell assembly 20, and the other end of the bent portion 211 is connected to the extension portion 212.

[0080] On the dummy plane, the projection of the fastener 323 covers the projection of the extension 212, increasing the contact area between the fastener 323 and the tab 21 and increasing the structural strength.

[0081] Along the first direction, the minimum width of the extension 212 is g, where 4mm ≤ g ≤ 20mm. For example, 8mm ≤ g ≤ 16mm. It should be noted that the tab 21 has multiple layers, and misalignment may occur during winding or bending, resulting in uneven width of the tab 21, with a minimum width of g. In some embodiments, the misaligned portion can be trimmed, or tabs 21 of unequal height can be used, so that the width of the multi-layered tabs 21 after winding and bending is uniform and the edges are flush. In this case, the width of the multi-layered tabs 21 is g.

[0082] For example, along the first direction, the width of the cover plate 31 is b, and the minimum width of the extension 212 is g, wherein 4% ≤ g / b ≤ 30%. If g / b is less than 4%, the width ratio of the tab 21 is too small, making it difficult to ensure sufficient current flow. If g / b is greater than 30%, the width ratio of the tab 21 is too large, easily leading to problems such as folding and inverted insertion. Preferably, 10% ≤ g / b ≤ 25%. For example, along the first direction, the width of the cover plate 31 is b, and the minimum width of the extension 212 is g, with the g / b value being 4%, 5%, 6%, 8%, 10%, 12%, 15%, 16%, 18%, 20%, 25%, or 30%.

[0083] See Figure 16 and Figure 17This embodiment also provides an electrical device, including the aforementioned battery cell 120. The electrical device can directly use the battery cell 120, or it can use a battery pack 100. The battery pack 100 includes a battery housing 110 and multiple battery cells 120 disposed inside the battery housing 110. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Among them, electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0084] In some embodiments, the electrical device can be a gasoline-powered vehicle or a new energy vehicle, such as a pure electric vehicle, a hybrid electric vehicle, or a range-extended electric vehicle. The electrical device internally houses a battery pack 100. The battery pack 100 can be used to power the electrical device; for example, the battery pack 100 can serve as the operating power source for the electrical device. The electrical device may also include a controller and a motor. The controller controls the battery pack 100 to supply power to the motor, for example, to meet the power requirements of the electrical device during startup, navigation, and operation.

[0085] The above embodiments merely illustrate the basic principles and characteristics of this utility model. This utility model is not limited to the above embodiments. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A battery cell, characterized in that, include: The outer shell (10) has an opening at at least one end; A battery cell assembly (20) is disposed within the housing (10), and the battery cell assembly (20) has tabs (21); The battery top cover (30) includes a cover plate (31) and a terminal post (32). The cover plate (31) closes the opening of the outer casing (10). The terminal post (32) is disposed on the cover plate (31). The terminal post (32) includes a first connecting portion (321) distributed along a first direction and at least two second connecting portions (322). The second connecting portions (322) are used to connect with the tab (21) so that a third welding area is formed on the tab (21). Along the first direction, the distance between the third welding area and the edge of the cover plate (31) is d1, where 3mm≤d1≤15mm.

2. The battery cell according to claim 1, characterized in that, The pole post (32) also includes a fixing member (323), which includes a first connecting area and a second connecting area. The first connecting area is connected to the second connecting part (322), and the second connecting area is connected to the third welding area.

3. The battery cell according to claim 2, characterized in that, Along the first direction, the distance between the edge of the fastener (323) and the edge of the cover plate (31) is f, where 1mm≤f≤10mm.

4. The battery cell according to claim 2, characterized in that, The tab (21) includes a bent portion (211) and an extension portion (212). The extension portion (212) is located on one side of the fastener (323) along a second direction. On a dummy plane perpendicular to the second direction, at least a portion of the orthographic projection of the extension portion (212) is located outside the orthographic projection of the second connecting portion (322). The first direction intersects the second direction.

5. The battery cell according to claim 4, characterized in that, On the dummy plane, the projection of the fastener (323) overlaps the projection of the extension (212).

6. The battery cell according to claim 4, characterized in that, Along the first direction, the width of the cover plate (31) is b, and the minimum width of the extension (212) is g, wherein 4% ≤ g / b ≤ 30%.

7. The battery cell according to claim 2, characterized in that, The second connecting portion (322) includes a first metal layer (3221) and a second metal layer (3222). The second metal layer (3222) is located on the side of the first metal layer (3221) close to the fastener (323). The first connecting portion (321) includes the first metal layer (3221), and the second metal layer (3222) is connected to the fastener (323).

8. The battery cell according to claim 1, characterized in that, A first insulating element (34) is provided between the pole post (32) and the cover plate (31). Along the first direction, the distance between the edge of the first insulating element (34) and the edge of the cover plate (31) is a, where 4mm≤a≤20mm.

9. The battery cell according to claim 1, characterized in that, Along the first direction, the width of the second connecting part (322) is c, and the width of the pole post (32) is e, wherein 8% ≤ c / e ≤ 35%.

10. An electrical appliance, characterized in that, Includes the battery cell described in any one of claims 1-9.

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