Battery cell and battery pack

Abstract

The utility model relates to the technical field of batteries, and discloses a battery cell and a battery pack, and the battery cell comprises a shell, a pole group, a pole post and a connecting sheet, according to the battery cell with the structure, the connecting sheets are bent upwards, and the outward concave areas are arranged on the pole columns, so that the internal space of the pole columns is fully utilized to provide upward bending space for the connecting sheets under the condition that the external occupied space of the pole columns is not changed, and the space occupied by downward bending of the connecting sheets is saved, so that the space utilization rate of the battery cell is effectively improved, and the service life of the battery cell is prolonged. And the energy density of the battery cell is improved. The full tabs are arranged at the end parts of the pole groups and are attached to the end surfaces of the pole groups, so that the space occupied by the tabs can be effectively reduced, and the space utilization rate of the battery cell can be further improved; meanwhile, the welding position of the connecting piece and the pole is positioned in the pole, so that the welding position of the connecting piece and the pole is far away from the lower plastic, the influence of high welding temperature on the lower plastic can be effectively avoided during welding, the thermal melting of the lower plastic is avoided, and the safety and reliability of the battery can be effectively ensured.

Description

Technical Field

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

[0002] The battery cell includes structures such as a housing, an electrode assembly, and a cover plate. The electrode assembly is arranged inside the housing. An electrode tab 1' is provided at the end of the electrode assembly. The cover plate 2' is arranged on the opening of the housing. As Figure 1 shown, when the battery cell is assembled, one side of the connecting piece 3' is first welded to the bottom plate of the pole column 4'. The other side of the connecting piece is bent towards the inside of the housing to form a connecting portion, and the connecting portion is welded to the electrode tab. The space utilization rate of the battery cell with such a structure is low; and when the connecting piece is welded to the bottom plate of the pole column, the welding position is close to the lower plastic 5', and there is a risk that the lower plastic will be thermally melted and fail during welding. Content of the Utility Model

[0003] In view of this, the utility model provides a battery cell and a battery pack to solve the problems of low space utilization rate of the existing battery cell and thermal melting failure of the lower plastic of the battery cell.

[0004] In the first aspect, the utility model provides a battery cell, including:

[0005] A housing;

[0006] An electrode assembly, arranged inside the housing, and an all-pole ear is provided at the end of the electrode assembly;

[0007] A pole column, including a body part, the body part is arranged on the housing or the cover plate of the battery cell; a surface of the body part located inside the housing or the cover plate is recessed towards the outside of the housing to form an outwardly recessed area, and the body part outside the outwardly recessed area is a first connecting portion;

[0008] A connecting piece, including a second connecting portion, a connecting portion and a third connecting portion. Among them, the second connecting portion is arranged inside the pole column, and the second connecting portion is electrically connected to the all-pole ear; one end of the connecting portion is connected to the second connecting portion, and the other end of the connecting portion extends towards the outwardly recessed area; the third connecting portion is connected to the other end of the connecting portion, the third connecting portion extends in the same direction as the second connecting portion, and the third connecting portion is electrically connected to the first connecting portion.

[0009] Beneficial effects: In the battery cell of this structure, an outward recessed area is provided on the pole, and the connecting portion of the connecting piece is bent toward the outer side of the shell and extends for a distance, and then bent toward the first connecting portion to form a third connecting portion, and the third connecting portion is electrically connected to the first connecting portion, thereby realizing the electrical connection between the connecting piece and the pole. The connecting piece is bent upward, and an outward recessed area is provided on the pole. When the space occupied by the outer contour of the pole remains unchanged, the space inside the pole is fully utilized to provide space for the connecting piece to bend upward, saving the space inside the shell occupied by the connecting piece bending downward. The battery cell can fully utilize the space inside the shell to set a larger pole group, thereby effectively improving the space utilization rate of the battery cell and improving the energy density of the battery cell. A full pole ear is arranged at the end of the pole group, and the full pole ear is attached to the end face of the pole group, which can effectively reduce the space occupied by the pole ear and further improve the space utilization rate of the battery cell; at the same time, the welding position of the connecting piece and the pole is located inside the pole, so that the welding position of the connecting piece and the pole is far away from the lower plastic, which can effectively avoid the influence of high welding temperature on the lower plastic during welding, avoid the heat melting of the lower plastic, and effectively ensure the safety and reliability of the battery.

[0010] In an optional embodiment, the connecting piece has a symmetrical structure, and the connecting portion is located in the middle of the connecting piece.

[0011] Beneficial effects: The connecting piece has a symmetrical structure and the overall structural stability of the connecting piece is good.

[0012] In an optional embodiment, along a direction perpendicular to a symmetry line of the connecting piece, a length of the second connecting portion is greater than a length of the third connecting portion.

[0013] Beneficial effect: The length of the second connecting portion is greater than that of the third connecting portion, so that the entire connection forms an "I"-shaped structure, which can ensure the strength of the connecting piece and improve the stability of the structure after the battery cell is assembled.

[0014] In an optional embodiment, the second connecting portion, the connecting portion and the third connecting portion are integrally arranged to form a semi-directional connecting portion, and two groups of the semi-directional connecting portions are provided. The two groups of the semi-directional connecting portions are arranged back to back, and the two groups of the connecting portions are electrically connected.

[0015] Beneficial effect: When the connecting piece is manufactured, each half-way connecting part is bent separately, and then two groups of half-way connecting parts are butt-connected to form an integral structure, which facilitates the bending and forming of the connecting piece and avoids damage and tearing of the connecting piece due to excessive bending.

[0016] In an alternative embodiment, a through hole is provided in the middle region of the first connecting portion, and an inwardly recessed area is formed by the body portion outside the through hole being recessed towards the inside of the housing. The through hole communicates with the outwardly recessed area and the inwardly recessed area; the connecting portion is inserted through the through hole, and the third connecting portion is bent towards the outer wall surfaces of the first connecting portion on both sides of the through hole.

[0017] Advantageous effects: The third connecting portion is bent towards the outer wall surfaces of the first connecting portion on both sides of the through hole, so that the third connecting portion can be lapped on the first connecting portion, and the third connecting portion is supported by the first connecting portion, which is beneficial to ensuring the stability of the connecting piece structure. The setting of the through hole also facilitates the bending and forming of the connecting piece and the assembly of the battery cell.

[0018] In an alternative embodiment, the pole column further includes an end sealing portion, and the end sealing portion is arranged in the inwardly recessed area, and the end sealing portion is in sealing cooperation with the body portion.

[0019] Advantageous effects: The end sealing portion is arranged in the inwardly recessed area, and the end sealing portion is in sealing cooperation with the body portion, so that the pole column forms a sealed structure as a whole, and the connecting piece is sealed inside the pole column, which can ensure the overall sealing performance of the battery cell.

[0020] In an alternative embodiment, it further includes a first insulating member, a sealing member and a second insulating member. A pole column hole is provided on the housing or the cover plate; the first connecting portion is arranged in the pole column hole, the first insulating member is arranged on the outer wall surface of the housing or the cover plate, and the second insulating member is arranged on the inner wall surface of the housing or the cover plate;

[0021] The body portion outside the periphery of the inwardly recessed area is an outer limiting portion, and the body portion outside the periphery of the outwardly recessed area is an inner limiting portion. The outer limiting portion abuts against the first insulating member, and the inner limiting portion abuts against the second insulating member.

[0022] Advantageous effects: The outer limiting portion limits the first insulating member, and the inner limiting portion limits the second insulating member.

[0023] In an alternative embodiment, the thickness of the connecting piece is A, and 0.4 mm ≤ A ≤ 0.8 mm;

[0024] And / or, the distance between the inner end surface of the body portion and the second connecting portion is B, and 0.5 mm ≤ B ≤ 1 mm.

[0025] In an alternative embodiment, the pole column further includes an end sealing portion, and the height of the outwardly recessed area is C, and 1.5 mm ≤ C ≤ 2.3 mm;

[0026] And / or, the thickness of the first connecting portion is D, where 1.2 mm ≤ D ≤ 1.8 mm;

[0027] The distance between the inner end face of the end sealing portion and the outer end face of the first connecting portion is E, where 1 mm ≤ E ≤ 1.5 mm;

[0028] And / or, the width of the through hole is F, where 2.4 mm ≤ F ≤ 3.6 mm.

[0029] In a second aspect, the present utility model further provides a battery pack, including the battery cell described in any one of the above. The battery pack includes the battery cell and has the same technical effects as the battery cell, which will not be elaborated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the specific embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0031] Figure 1 It is a cross-sectional view of the battery cell described in the background art of the present utility model;

[0032] Figure 2 It is a three-dimensional structure diagram of a battery cell according to an embodiment of the present utility model;

[0033] Figure 3 It is a top view of a battery cell according to an embodiment of the present utility model;

[0034] Figure 4 For Figure 3 A-A cross-sectional view of

[0035] Figure 5 For Figure 4 A partial enlarged view of part A in

[0036] Figure 6 For Figure 5 A three-dimensional structure diagram of the connecting piece in

[0037] Figure 7 For Figure 5 A top view of the connecting piece in

[0038] Figure 8 For Figure 7 A B-B cross-sectional view of

[0039] Figure 9 It is a schematic diagram of the cooperation of the housing, the pole column, the first insulating member, the sealing member and the second insulating member in a battery cell according to an embodiment of the present utility model;

[0040] Figure 10 Cross-sectional view of a battery cell during assembly according to an embodiment of the present utility model;

[0041] Figure 11 Schematic perspective view of a battery cell during assembly according to an embodiment of the present utility model;

[0042] Figure 12 Schematic partial structure view of the cooperation of the housing, pole column and pole group in a battery cell according to an embodiment of the present utility model.

[0043] Explanation of reference numerals:

[0044] 1', tab; 2', cover plate; 3', connecting piece; 4', pole column; 5', lower plastic;

[0045] 1, housing; 2, pole group; 3, pole column; 31, body part; 311, outwardly concave area; 312, first connection part; 313, through hole; 314, inwardly concave area; 315, external limiting part; 316, internal limiting part; 32, end sealing part; 4, connecting piece; 41, semi-directional connection part; 411, second connection part; 412, connection part; 413, third connection part; 5, first insulating part; 6, sealing part; 7, second insulating part. Detailed implementation manners

[0046] 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. Obviously, the described embodiments are part of the embodiments of the present utility model, rather than all of the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0047] As Figure 1 shown, in the related art, the pole column is arranged on the cover plate 2'. One side of the connecting piece 3' is first welded to the bottom plate of the pole column 4'. In order to make the welding position of the connecting piece 3' and the tab 1' far from the lower plastic, the other side of the connecting piece is bent inward to the inside of the housing to form a connecting part, and the connecting part is then welded to the pole group. In this structure, the connecting piece extends a certain distance in the direction of the pole group and then bends and is connected to the tab. The connecting piece occupies the space inside the housing in the height direction of the battery cell, resulting in low space utilization rate of the battery cell. And although this structure makes the welding position of the connecting piece and the tab far from the lower plastic 5', the welding position of the connecting piece and the pole column is still close to the lower plastic, and there is still a risk of thermal melting failure of the lower plastic during welding.

[0048] Next, in combination with Figures 2 to 12 , the embodiments of the present invention will be described.

[0049] According to an embodiment of the present invention, on the one hand, a battery cell is provided, which includes a housing 1, an electrode assembly 2, a terminal 3, and a connecting piece 4.

[0050] Wherein, the electrode assembly 2 is arranged in the housing 1, and a full tab is provided at the end of the electrode assembly 2; the terminal 3 includes a body portion 31, and the body portion 31 is arranged on the housing 1 or the cover plate of the battery cell; one side of the body portion 31 located inside the housing 1 or the cover plate is recessed towards the outside of the housing 1 to form an outward recessed area 311, and the body portion 31 outside the outward recessed area 311 is a first connecting portion 312. The connecting piece 4 includes a second connecting portion 411, a connecting portion 412, and a third connecting portion 413. Wherein, the second connecting portion 411 is arranged inside the terminal 3, and the second connecting portion 411 is electrically connected to the full tab; one end of the connecting portion 412 is connected to the second connecting portion 411, and the other end of the connecting portion 412 extends towards the outward recessed area 311; the third connecting portion 413 is connected to the other end of the connecting portion 412, the third connecting portion 413 extends in the same direction as the second connecting portion 411, and the third connecting portion 413 is electrically connected to the first connecting portion 312.

[0051] For the battery cell with this structure, an outward recessed area 311 is provided on the terminal 3. After the connecting portion 412 of the connecting piece 4 is bent towards the outside of the housing 1 and extends for a certain distance, it is then bent towards the first connecting portion to form the third connecting portion 413, and the third connecting portion 413 is electrically connected to the first connecting portion 312, thereby realizing the electrical connection between the connecting piece 4 and the terminal 3. The connecting piece 4 is bent upwards, and an outward recessed area 311 is provided on the terminal 3. Without changing the occupied space of the outer contour of the terminal 3, the space inside the terminal 3 is fully utilized to provide space for the upward bending of the connecting piece 4, saving the space inside the housing 1 occupied by the downward bending of the connecting piece 4. The battery cell can fully utilize the space inside the housing 1 to set a larger electrode assembly 2, thereby effectively improving the space utilization rate of the battery cell and increasing the energy density of the battery cell. A full tab is provided at the end of the electrode assembly 2, and the full tab is attached to the end face of the electrode assembly 2, which can effectively reduce the occupied space of the tab and further improve the space utilization rate of the battery cell; at the same time, the welding position of the connecting piece 4 and the terminal 3 is located inside the terminal 3, so that the welding position of the connecting piece 4 and the terminal 3 is far from the lower plastic, and the influence of the welding high temperature on the lower plastic can be effectively avoided during welding, preventing the lower plastic from melting thermally, and effectively ensuring the safety and reliability of the battery.

[0052] As Figures 5 to 8 and Figure 12 shown, in some embodiments, the connecting piece 4 has a symmetrical structure, the connecting portion 412 is located in the middle of the connecting piece 4, and the overall structural stability of the connecting piece 4 is good; and the second connecting portions 411 on both sides of the connecting portion 412 can be respectively connected to two groups of tabs, so that the connecting piece 4 can be adapted to the battery cell with a bipolar electrode assembly 2.

[0053] In some embodiments, along the direction perpendicular to the symmetry line of the connecting piece 4 ( Figure 8 In the left-right direction, that is, the thickness direction of the battery cell), the length of the second connecting portion 411 is greater than the length of the third connecting portion 413, so that the overall connection forms an "I"-shaped structure, which can ensure the strength of the connecting sheet 4 and improve the stability of the structure after the battery cell is assembled.

[0054] like Figure 6 and Figure 8 As shown, in some embodiments, the second connection part 411, the connecting part 412 and the third connection part 413 are integrally arranged to form a semi-directional connection part 41, and the semi-directional connection part 41 is provided with two groups, and the two groups of semi-directional connection parts 41 are arranged opposite to each other, and the two groups of connecting parts 412 are electrically connected. After the two groups of connecting parts 412 are electrically connected, the two groups of semi-directional connection parts 41 are connected to form an integral structure. The connecting sheet 4 is a multi-layer structure, which is formed by welding and connecting multiple layers of metal plates to form a sheet structure, one end of the sheet structure is bent upward to form a connecting part 412, and the connecting part 412 is then bent horizontally to form the third connection part 413. When the connecting sheet 4 is manufactured and formed, each semi-directional connection part 41 can be bent separately, and then the two groups of semi-directional connection parts 41 are connected and connected to form an integral structure, so as to facilitate the bending and forming of the connecting sheet 4, and avoid the bending transition of the connecting sheet 4 and damage and tearing.

[0055] like Figure 5 and Figure 8 As shown, an arc-shaped bending area is provided between the second connection part 411 and the connecting part 412, and between the connecting part 412 and the third connection part 413. The arc-shaped bending area can make a smooth transition between adjacent sections of the semi-connecting part 41, and reduce burrs generated at the bending part during processing of the connecting piece 4. Since the transition area between the second connection part 411 and the connecting part 412 is close to the electrode group 2, the provision of the arc-shaped bending area can effectively prevent the sharp-angle structure from contacting the electrode group 2 and piercing the diaphragm, thereby preventing a short circuit inside the battery cell.

[0056] like Figure 2 , Figure 3 and Figure 11 As shown, the longitudinal section of the connecting piece 4 is in an "I" shape, perpendicular to the longitudinal section direction of the connecting piece 4 (i.e., the length direction of the battery cell), the second connecting portion 411, the connecting portion 412, and the third connecting portion 413 extend to a certain length, which can increase the electrical connection area with the full tab and the pole 3 and improve the current capacity. Accordingly, the tab and the pole 3 extend along the length direction of the battery cell.

[0057] Optionally, in some embodiments, the two groups of connecting portions 412 are welded together, the second connecting portion 411 is welded to the full tab, and the third connecting portion 413 is welded to the first connecting portion 312 .

[0058] The connecting piece 4 includes a positive connecting piece and a negative connecting piece. The positive connecting piece is formed by welding and bending multiple layers of aluminum plates, and the negative connecting piece is formed by welding and bending multiple layers of copper plates.

[0059] As Figure 5 and Figure 9 shown, in some embodiments, a through hole 313 is provided in the middle region of the first connecting portion 312. An inwardly recessed area 314 is provided on the body portion 31 outside the through hole 313. The through hole 313 communicates with the outwardly recessed area 311 and the inwardly recessed area 314. The connecting portion 412 is inserted into the through hole 313. The third connecting portion 413 is bent towards the outer wall surfaces of the first connecting portions 312 on both sides of the through hole 313, so that the third connecting portion 413 can overlap on the first connecting portion 312. By supporting the third connecting portion 413 with the first connecting portion 312, it is beneficial to ensure the structural stability of the connecting piece 4. At the same time, when assembling the battery cell, the connecting portion 412 and the third connecting portion 413 are in a vertical state and perpendicular to the second connecting portion 411. When the connecting piece 4 is assembled into the housing 1, the connecting portion 412 and the third connecting portion 413 vertically extend outwards through the through hole 313. Then, the third connecting portion 413 is bent by a bending tooling, so that the third connecting portion 413 is attached to the outer surface of the first connecting portion 312, and then the third connecting portion 413 is welded to the first connecting portion 312, which is convenient for the connecting piece 4 to be bent and formed and for assembling the battery cell.

[0060] In other embodiments, the through hole 313 may not be provided on the body portion 31. The connecting portion 412 extends towards the outwardly recessed area 311 for a certain distance. The third connecting portion 413 is bent towards the bottom surface of the first connecting portion 312, and the third connecting portion 413 is welded and fixed to the bottom surface of the first connecting portion 312.

[0061] As Figure 5 and Figure 12 shown, in some embodiments, the pole 3 further includes an end sealing portion 32. The end sealing portion 32 is disposed in the inwardly recessed area 314. The end sealing portion 32 is in sealing cooperation with the body portion 31, so that the whole pole 3 forms a sealing structure, and the connecting piece 4 is sealed inside the pole 3, which can ensure the overall sealing of the battery cell.

[0062] Optionally, the material of the end sealing portion 32 is the same as that of the body portion 31, and the top surface of the end sealing portion 32 is flush with the top surface of the body portion 31.

[0063] When the battery cell is provided with a cover plate, the pole 3 is disposed on the cover plate. When the battery cell is provided with a cover plate, the pole 3 is disposed on the housing 1. For example, in some embodiments, the pole 3 is disposed on the housing 1.

[0064] Optionally, in some embodiments, the battery includes a cylindrical battery cell.

[0065] In other embodiments, the battery may further include a square shell battery cell. Here, the embodiments of the present invention will be described by taking the square shell battery cell as an example.

[0066] As Figure 5 shown, in some embodiments, the inner wall of the inwardly recessed area 314 is further provided with a stepped structure, and the bottom surface of the end sealing portion 32 is lapped on the stepped surface of the stepped structure, which is convenient for positioning and welding the end sealing portion 32. The bottom surface of the end sealing portion 32 is spaced from the top surface of the connecting piece 4 by a certain distance to provide space for the welding mark between the connecting piece 4 and the first connecting portion 312.

[0067] The battery cell further includes a first insulating member 5, a sealing member 6 and a second insulating member 7. A pole hole is provided on the housing 1 or the cover plate; the first connecting portion 312 is disposed in the pole hole, the first insulating member 5 is disposed on the outer wall surface of the housing 1 or the cover plate, and the second insulating member 7 is disposed on the inner wall surface of the housing 1 or the cover plate; the body portion 31 outside the inwardly recessed area 314 is an outer limiting portion 315, and the body portion 31 outside the outwardly recessed area 311 is an inner limiting portion 316. The outer limiting portion 315 abuts against the first insulating member 5, and the inner limiting portion 316 abuts against the second insulating member 7. The outer limiting portion 315 limits the first insulating member 5, and the inner limiting portion 316 limits the second insulating member 7.

[0068] As Figure 5 shown, the outer limiting portion 315 is located outside the housing 1, the inner limiting portion 316 is located inside the housing 1, and the widths of the inner limiting portion 316 and the outer limiting portion 315 extending in the thickness direction of the battery cell are greater than the width of the body portion 31 at the position where the first connecting portion 312 is located. The inner limiting portion 316 and the outer limiting portion 315 limit the pole 3 and fix the pole 3 on the housing 1.

[0069] Optionally, the first insulating member 5 includes an upper plastic, the sealing member 6 includes a sealing ring, and the second insulating member 7 includes a lower plastic. A pole hole is provided on the housing 1. The sealing ring is disposed in the body portion 31 and the pole hole of the housing 1. The upper plastic is disposed outside the housing 1, and the other side of the upper plastic extends into the pole hole; the lower plastic is located inside the housing 1, and one end of the lower plastic facing the sealing ring is connected to the sealing ring. The outer limiting portion 315 abuts against the upper plastic, and the inner limiting portion 316 abuts against the lower plastic, thereby riveting and fixing the upper plastic, the sealing ring and the lower plastic.

[0070] In some embodiments, as Figure 12 shown, the thickness of the connecting piece 4 is A, 0.4 mm ≤ A ≤ 0.8 mm. The thickness of the connecting piece 4 is appropriate, so that the connecting piece 4 can stably maintain the required shape after being bent.

[0071] Preferably, in some embodiments, the thickness of the connecting piece 4 is 0.6 mm.

[0072] In some embodiments, the second connecting portion 411 and the full tab are welded, and there is a welding mark on the side of the second connecting portion 411 facing the body portion 31. As Figure 12 shown, the distance between the inner end face of the body portion 31 and the second connecting portion 411 is B, that is, the distance between the end face of the end of the body portion 31 facing the electrode group 2 and the side of the second connecting portion 411 facing the body portion 31 is B, 0.5 mm ≤ B ≤ 1 mm. An appropriate distance is maintained between the body portion 31 and the second connecting portion 411 to provide a space for accommodating the welding mark, and at the same time, to avoid an excessive distance, which can further effectively ensure the space utilization rate of the battery cell.

[0073] Preferably, in some embodiments, the value of B is 0.7 mm, 1 A ≤ B ≤ 1.5 A.

[0074] As Figure 12 shown, in some embodiments, the height of the outwardly concave area 311 is C, 1.5 mm ≤ C ≤ 2.3 mm. The height of the outwardly concave area 311 is appropriate, which can provide sufficient space for the upward bending of the connecting piece 4, and at the same time, it can avoid waste of space utilization due to an excessive height of the outwardly concave area 311.

[0075] Preferably, in some embodiments, C is 1.9 mm.

[0076] In some embodiments, as Figure 12 shown, the thickness of the first connecting portion 312 is D, 1.2 mm ≤ D ≤ 1.8 mm. Since the third connecting portion 413 and the first connecting portion 312 are laser welded, and there is a certain welding penetration in laser welding, the thickness D of the first connecting portion 312 satisfies 1.2 mm ≤ D ≤ 1.8 mm, which can make its thickness greater than the welding penetration, ensure the strength and stability of the welding position after the third connecting portion 413 and the first connecting portion 312 are welded, and thus ensure the electrical connection effect between the connecting piece 4 and the pole 3.

[0077] Preferably, in some embodiments, D is 1.5 mm, 0.6C ≤ D ≤ C.

[0078] As Figure 12 shown, in some embodiments, the distance between the inner end face of the end sealing portion 32 and the outer end face of the first connecting portion 312 is E, 1 mm ≤ E ≤ 1.5 mm. The existence of the distance E makes the side of the end sealing portion 32 opposite to the third connecting portion 413 arranged at intervals to provide a space for accommodating the welding mark on the third connecting portion.

[0079] Optionally, 1.5 A ≤ E ≤ 2 A.

[0080] In some embodiments, the width of the through hole 313 is F, where 2.4 mm ≤ F ≤ 3.6 mm. The width of the through hole 313 is moderate, providing sufficient space for the bending of the connecting piece 4, ensuring that the turning bending part of the connecting piece 4 can be bent in an arc shape, preventing the bending part from rubbing against the first connecting portion 312, and avoiding tearing at the bending part of the connecting piece 4.

[0081] According to an embodiment of the present invention, on the other hand, a battery pack is provided, including the above-mentioned battery cell. For the battery pack with such a structure, since the connecting piece 4 is bent upward, the space inside the housing 1 can be fully utilized to arrange the electrode group 2, thereby effectively improving the space utilization rate of the battery cell, and further improving the space utilization rate and energy density of the battery pack.

[0082] Although the 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 all fall within the scope defined by the appended claims.

Claims

1. A battery cell, characterized in that, Comprising: A housing; An electrode assembly, disposed within the housing, and an end of the electrode assembly is provided with a full tab; A terminal, including a body portion, the body portion is disposed on the housing or on a cover plate of the battery cell; a surface of the body portion facing the outside of the housing within the housing or the cover plate is recessed outward to form an outward recessed area, and the body portion outside the outward recessed area is a first connection portion; A connecting piece, including a second connection portion, a connecting portion, and a third connection portion. Among them, the second connection portion is disposed inside the terminal, and the second connection portion is electrically connected to the full tab; one end of the connecting portion is connected to the second connection portion, and the other end of the connecting portion extends toward the outward recessed area; the third connection portion is connected to the other end of the connecting portion, the third connection portion extends in the same direction as the second connection portion, and the third connection portion is electrically connected to the first connection portion.

2. The battery cell according to claim 1, characterized in that The connecting piece has a symmetrical structure, and the connecting portion is located in the middle of the connecting piece.

3. The battery cell according to claim 2, wherein, Along a direction perpendicular to the symmetry line of the connecting piece, the length of the second connection portion is greater than the length of the third connection portion.

4. The battery cell according to claim 2 or 3, characterized in that, The second connection portion, the connecting portion, and the third connection portion are integrally provided to form a semi-directional connection portion. There are two sets of the semi-directional connection portions, and the two sets of the semi-directional connection portions are arranged back to back, and the two sets of the connecting portions are electrically connected.

5. The battery cell according to any one of claims 1 to 3, characterized in that, A through hole is provided in a middle area of the first connection portion, and a surface of the body portion outside the through hole facing the inside of the housing is recessed inward to form an inward recessed area. The through hole communicates the outward recessed area and the inward recessed area; the connecting portion is inserted into the through hole, and the third connection portion bends toward an outer wall surface of the first connection portion on both sides of the through hole.

6. The battery cell according to claim 5, wherein The terminal further includes an end sealing portion, the end sealing portion is disposed in the inward recessed area, and the end sealing portion is in sealing cooperation with the body portion.

7. The battery cell according to claim 5, characterized in that It further includes a first insulating member, a sealing member, and a second insulating member. A terminal hole is provided on the housing or the cover plate; the first connection portion is disposed in the terminal hole, the first insulating member is disposed on an outer wall surface of the housing or the cover plate, and the second insulating member is disposed on an inner wall surface of the housing or the cover plate; The body portion outside the inward recessed area is an outer limiting portion, and the body portion outside the outward recessed area is an inner limiting portion. The outer limiting portion abuts against the first insulating member, and the inner limiting portion abuts against the second insulating member.

8. The battery cell according to any one of claims 1 to 3, characterized in that, The thickness of the connecting piece is A, and 0.4 mm ≤ A ≤ 0.8 mm; And / or, the distance between an inner end surface of the body portion and the second connection portion is B, and 0.5 mm ≤ B ≤ 1 mm.

9. The battery cell according to claim 5, wherein, The terminal further includes an end sealing portion, and the height of the outward recessed area is C, and 1.5 mm ≤ C ≤ 2.3 mm; And / or, the thickness of the first connection portion is D, and 1.2 mm ≤ D ≤ 1.8 mm; The distance between an inner end surface of the end sealing portion and an outer end surface of the first connection portion is E, and 1 mm ≤ E ≤ 1.5 mm; And / or, the width of the through hole (313) is F, and 2.4 mm ≤ F ≤ 3.6 mm.

10. A battery pack, characterized in that, Including the battery cell according to any one of claims 1 to 9.

Images