Battery cell and battery pack

Abstract

The utility model relates to the technical field of batteries, discloses a battery cell and a battery pack, and aims to improve the connection strength between a metal piece and an insulating piece and ensure the reliability of the battery cell. The battery cell comprises a shell provided with an opening; the pole group is arranged in the shell; an electrode terminal mounted on the case; at least part of the structure of the electrode terminal is located in the shell and is electrically connected with the electrode group; the opening is arranged to allow the electric connection part of the electrode terminal and the pole group to be exposed; the insulating sealing element comprises a metal piece and an insulating piece which is formed on one side of the metal piece through injection molding; the metal piece is connected with the shell and blocks the opening; the insulating piece is positioned on one side, close to the pole group, of the metal piece; a groove and a boss which are mutually embedded and connected are arranged between the metal piece and the insulating piece; the groove is formed in the first one of the metal piece and the insulating piece, and an annular convex rib is arranged at the position, surrounding a notch of the groove, of the first one of the metal piece and the insulating piece; the boss is arranged on the second one of the metal piece and the insulating piece, and the annular convex rib is clamped on the peripheral side of the boss.

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] A battery cell generally includes structures such as a housing, an electrode assembly, a connecting piece, a terminal, etc. Among them, the airtightness inside the battery cell and the insulation between various structures are key factors to ensure the normal operation of the battery cell.

[0003] In some technical solutions, for the convenience of assembly or other considerations, an opening is provided on the housing. After assembly, a sealing member and an insulating member need to be provided at the opening to ensure the airtightness inside the battery cell and the insulation between the sealing member and other structures. However, the insulating member is prone to move or even shift inside the sealing member, resulting in insulation failure between the sealing member and other structures and affecting the reliability of the battery cell. Summary of the Utility Model

[0004] The purpose of the utility model is to overcome the defect that in the related art, due to the movement or displacement of the insulating member, it is easy to cause insulation failure between the sealing member and other structures and reduce the reliability of the battery cell, so as to provide a battery cell and a battery pack.

[0005] In a first aspect, the utility model provides a battery cell, including: a housing provided with an opening; an electrode assembly disposed inside the housing; an electrode terminal mounted on the housing; at least part of the structure of the electrode terminal is located inside the housing and is electrically connected to the electrode assembly; the opening is set to allow the electrical connection part of the electrode terminal and the electrode assembly to be exposed; an insulating seal including a metal part and an insulating part injection-molded on one side of the metal part; the metal part is connected to the housing and seals the opening, and the insulating part is located on the side of the metal part close to the electrode assembly; there are mutually engaged and connected grooves and protrusions between the metal part and the insulating part; the groove is provided in the first of the metal part and the insulating part, and a circular rib is provided at the notch of the groove around the metal part and the first of the insulating part; the protrusion is provided in the second of the metal part and the insulating part, and the circular rib is clamped on the outer peripheral side of the protrusion.

[0006] Optionally, the first of the metal part and the insulating part is the metal part, and the second of the metal part and the insulating part is the insulating part; the circular rib is integrally formed on the metal part, and the protrusion is integrally formed on the insulating part.

[0007] Optionally, the thickness range of the metal part is 0.6 - 1.6 mm; the thickness range of the insulating part is 0.15 - 1.2 mm.

[0008] Optionally, the thickness range of the insulating seal is 1.2 - 1.8 mm.

[0009] Optionally, the thickness range of the annular rib is 0.25 - 0.55 mm, and the spacing range between the annular rib and the bottom wall of the groove is 0.25 - 0.55 mm.

[0010] Optionally, in the direction perpendicular to the thickness of the annular rib, the minimum inner diameter range of the annular rib is 0.35 - 1.2 mm.

[0011] Optionally, in the direction perpendicular to the thickness of the annular rib, the minimum width of the annular rib should be greater than or equal to 0.5 mm.

[0012] Optionally, both the opening and the insulating seal are provided with two.

[0013] Optionally, the housing has opposite first and second ends; two openings are located at the first end, and the two openings are spaced apart from each other; a liquid injection hole is further provided at the first end, and the liquid injection hole is located between the two openings; an explosion-proof valve is provided at the second end.

[0014] In a second aspect, the present utility model further provides a battery pack, including: at least one battery cell as described above.

[0015] By using the technical solution of the present utility model, a groove and a boss that are mutually fitted and connected are provided between the metal part and the insulating part. An annular rib is provided at the notch of the groove, and the annular rib is snap-fitted to the outer peripheral side of the boss. Among them, the boss is fitted and connected with the groove, which restricts the relative movement of the metal part and the insulating part on the connection surface of the two; the annular rib is snap-fitted to the outer peripheral side of the boss, which restricts the relative movement of the metal part and the insulating part in the thickness direction of the two, ensures the stability of the relative position and the connection strength between the metal part and the insulating part, and further ensures the insulation performance between the metal part and the electrode group, and improves the reliability of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] 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 drawings in the following description are some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0017] Figure 1 It is a schematic structural diagram of a battery cell according to an embodiment of the present utility model;

[0018] Figure 2 It is a schematic partial structural diagram of a battery cell according to an embodiment of the present utility model;

[0019] Figure 3 It is a schematic structural diagram of an insulating seal according to an embodiment of the present utility model;

[0020] Figure 4 A cross-sectional view of an insulating seal according to an embodiment of the present invention and a partial enlarged view thereof;

[0021] Figure 5 A schematic structural diagram of a metal part according to an embodiment of the present invention;

[0022] Figure 6 A cross-sectional view of a metal part according to an embodiment of the present invention and a partial enlarged view thereof;

[0023] Figure 7 A schematic structural diagram of an insulating part according to an embodiment of the present invention;

[0024] Figure 8 A cross-sectional view of an insulating part according to an embodiment of the present invention and a partial enlarged view thereof.

[0025] Explanation of reference numerals in the drawings:

[0026] 1. Housing; 11. First end; 12. Second end; 13. Opening; 14. Liquid injection hole;

[0027] 2. Electrode group; 21. Tab;

[0028] 3. Electrode terminal; 31. Terminal post; 32. Connecting piece;

[0029] 4. Insulating seal; 41. Metal part; 42. Insulating part; 43. Groove; 431. Flared part; 432. Necked-down part; 44. Boss; 441. End cap part; 442. Connecting part; 45. Annular rib; 46. Annular groove. Detailed implementation manners

[0030] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0031] The following combines Figures 1 to 8 , and describes the embodiments of the present invention.

[0032] Among them, Figure 1 A schematic structural diagram of a battery cell according to an embodiment of the present invention; Figure 2 A partial structural diagram of a battery cell according to an embodiment of the present invention, specifically a structural diagram when the insulating seal 4 is not provided at the opening 13 of the housing 1; Figure 3Schematic diagram of a structure of an insulating seal 4 according to an embodiment of the present invention; Figure 4 Cross-sectional view and partial enlarged view of an insulating seal 4 according to an embodiment of the present invention, Figure 4 wherein (a) is the cross-sectional view of the insulating seal 4, and the up-and-down direction thereof is the thickness direction of the insulating seal 4, Figure 4 and (b) in Figure 4 is the partial enlarged view of the A position in (a); Figure 5 Schematic diagram of a structure of a metal part 41 according to an embodiment of the present invention; Figure 6 Cross-sectional view and partial enlarged view of a metal part 41 according to an embodiment of the present invention, Figure 6 wherein (a) is the cross-sectional view of the metal part 41, and the up-and-down direction thereof is the thickness direction of the metal part 41, Figure 6 and (b) in Figure 6 is the partial enlarged view of the B position in (a); Figure 7 Schematic diagram of a structure of an insulating part 42 according to an embodiment of the present invention; Figure 8 Cross-sectional view and partial enlarged view of an insulating part 42 according to an embodiment of the present invention, Figure 8 wherein (a) is the cross-sectional view of the insulating part 42, and the up-and-down direction thereof is the thickness direction of the insulating part 42, Figure 8 and (b) in Figure 8 is the partial enlarged view of the C position in (a).

[0033] According to an embodiment of the present invention, a battery pack is provided, which includes at least one battery cell. It can be understood that the battery pack may include one, two or more battery cells. The present invention does not specifically limit the number of battery cells provided, as long as the design requirements are met.

[0034] Furthermore, as shown in Figure 1 and 2 , the battery cell includes a housing 1, a pole group 2 disposed in the housing 1, and an electrode terminal 3 mounted on the housing 1. Among them, at least part of the structure of the electrode terminal 3 is exposed outside the housing 1 for power transmission with external components, and at least part of the structure of the electrode terminal 3 is located inside the housing 1 and is electrically connected to the pole group 2. An opening 13 is provided on the housing 1, and the opening 13 is configured to allow the electrical connection part of the electrode terminal 3 and the pole group 2 to be exposed, so as to facilitate the electrical connection between the motor terminal and the pole group 2.

[0035] Further, the battery cell further includes an insulating seal 4 for sealing the opening 13. Specifically, the insulating seal 4 includes a metal part 41 and an insulating part 42 injection-molded on one side of the metal part 41. The metal part 41 is connected to the housing 1 and seals the opening 13 to ensure the airtightness inside the battery cell. Exemplarily, the metal part 41 is welded or bonded to the housing 1, etc. The insulating part 42 is located on the side of the metal part 41 close to the electrode group 2, that is, inside the metal part 41, and the insulating part 42 functions as insulation between the metal part 41 and the electrode group 2.

[0036] Further, a groove 43 and a boss 44 are provided between the metal part 41 and the insulating part 42 for fitting and connecting with each other. The groove 43 is provided on the first one of the metal part 41 and the insulating part 42, and an annular rib 45 is provided around the notch of the groove 43 on the first one of the metal part 41 and the insulating part 42. The boss 44 is provided on the second one of the metal part 41 and the insulating part 42, and the annular rib 45 is snap-fitted on the outer peripheral side of the boss 44.

[0037] In the insulating seal 4 arranged in this way, the boss 44 is fitted and connected with the groove 43, which restricts the relative movement of the metal part 41 and the insulating part 42 on their connection surface; the annular rib 45 is snap-fitted on the outer peripheral side of the boss 44, which restricts the relative movement of the metal part 41 and the insulating part 42 in their thickness direction, ensuring the stability of the relative position and the connection strength between the metal part 41 and the insulating part 42, and further ensuring the insulation performance between the metal part 41 and the electrode group 2, and improving the reliability of the battery cell.

[0038] Further, in some embodiments, as Figure 3 and 4 shown, the first one of the above-mentioned metal part 41 and the insulating part 42 is the metal part 41, and the second one of the metal part 41 and the insulating part 42 is the insulating part 42. Specifically, the groove 43 is provided on the side of the metal part 41 facing the insulating part 42, and the annular rib 45 is provided at the notch of the groove 43 on the metal part 41. The boss 44 is provided on the side of the insulating part 42 facing the metal part 41, and an annular card slot 46 is formed on the outer peripheral side of the boss 44, and the annular rib 45 is snap-fitted in the annular card slot 46. Among them, the annular rib 45 is integrally formed on the metal part 41, and the boss 44 is integrally formed on the insulating part 42. Arranged in this way, it is easy to manufacture the metal part 41 and improve the production efficiency. Before molding, the insulating part 42 has fluidity. When the insulating part 42 is injection-molded on the metal part 41, the injection material of the insulating part 42 can automatically fill into the groove 43 and form a boss 44 adapted to the shape of the groove 43.

[0039] Exemplarily, the metal part 41 can be a metal plate, and the metal plate can directly form the above-mentioned groove 43 and annular rib 45 through a stamping process, which is easy to manufacture. Exemplarily, the metal part 41 can be an aluminum plate.

[0040] Exemplarily, the insulating member 42 may be an insulating plate, which is formed on one side of the metal member 41 through an injection molding process. Exemplarily, the insulating member 42 may be made of polypropylene or other insulating materials.

[0041] It can be understood that the shape and structure of the metal member 41 depend on the shape and structure of the opening 13, so as to be able to block the opening 13. Exemplarily, if the opening 13 is a rectangular hole, the metal member 41 is a rectangular plate; Exemplarily, if the opening 13 is a circular hole, the metal member 41 is a circular plate. The shape and structure of the insulating member 42 depend on the metal member 41, that is, the shape and structure of the insulating member 42 also depend on the shape and structure of the opening 13, so as to be able to isolate the metal member 41 and the electrode group 2 and prevent them from contacting each other.

[0042] Such as Figure 3 and 4 As shown in the figure, in some embodiments, the metal member 41 is a rectangular metal plate, and the insulating member 42 is a rectangular insulating plate, and a partial structure of the metal member 41 along the circumferential direction extends out of the insulating member 42 for facilitating connection with the housing 1, such as welding.

[0043] Furthermore, in some embodiments, the thickness range of the metal member 41 is 0.6 - 1.6 mm. As shown in Figure 4 and 6 the figure, the thickness of the metal member 41 refers to T1. T1 within this thickness range can ensure that the metal member 41 has sufficient structural strength.

[0044] In some embodiments, the thickness range of the insulating member 42 is 0.15 - 1.2 mm. As shown in Figure 4 and 8 the figure, the thickness of the insulating member 42 refers to T2. T2 within this thickness range can ensure the reliability of the structural strength and insulating performance of the insulating member 42.

[0045] In some embodiments, the thickness range of the insulating seal 4 is 1.2 - 1.8 mm. As shown in Figure 4 the figure, the thickness of the insulating seal 4 refers to T. T within this thickness range can not only ensure the structural strength of the metal member 41 and the insulating member 42, but also avoid occupying too much internal space of the battery cell. It can be understood that since there are mutually engaged grooves 43 and bosses 44 between the metal member 41 and the insulating member 42, the sum of T1 and T2 should be greater than T.

[0046] Furthermore, in some embodiments, the thickness range of the annular rib 45 is 0.25 - 0.55 mm, and the distance between the annular rib 45 and the bottom wall of the groove 43 ranges from 0.25 - 0.55 mm. As shown in Figure 4 and 6As shown, the thickness of the annular rib 45 is referred to as t1, and the spacing between the annular rib 45 and the bottom wall of the groove 43 is referred to as t2. When t1 is within this thickness range and t2 is within this spacing range, the strength of the cooperation between the groove 43 and the boss 44 can be ensured, and the tight fit between the metal part 41 and the insulating part 42 can be achieved.

[0047] Further, in some embodiments, in the direction perpendicular to the thickness direction of the annular rib 45, that is Figure 4 and Figure 6 in the left-right direction in, the minimum inner diameter range of the annular rib 45 is 0.35 - 1.2 mm, that is Figure 4 and Figure 6 the L in. As Figure 8 shown, at the root of the boss 44, that is, at the connection between the boss 44 and the main structure of the insulating part 42, it is formed within the annular rib 45, that is, the forming dimension of the root of the boss 44 depends on the inner diameter of the annular rib 45. When L is within this inner diameter range, the structural strength of the root of the boss 44 can be ensured, and further the structural strength of the insulating part 42 during the assembly and disassembly process can be ensured.

[0048] Further, in some embodiments, in the direction perpendicular to the thickness direction of the annular rib 45, the minimum width of the annular rib 45 should be greater than or equal to 0.5 mm. As Figure 4 and Figure 6 shown, the minimum width of the annular rib 45 is referred to as W. When W is greater than or equal to 0.5 mm, the cooperation effect between the annular rib 45 and the annular card slot 46 can be ensured, and the assembly strength between the metal part 41 and the insulating part 42 can be guaranteed.

[0049] Specifically, as Figure 5 and 6 shown, the groove 43 is recessed on one side of the metal part 41. The groove 43 includes a flared portion 431 and a necking portion 432 that are connected in sequence. The flared portion 431 is located at the bottom of the groove 43, and the necking portion 432 is located at the mouth of the groove 43. The port of the necking portion 432 away from the flared portion 431 forms the mouth of the groove 43. Among them, the set dimension of the flared portion 431 is larger than the set dimension of the necking portion 432, and in the direction from the bottom wall of the groove 43 to the mouth of the groove, the set dimension of the necking portion 432 shows a gradually decreasing trend. The necking portion 432 is formed inside the above-mentioned annular rib 45.

[0050] As Figure 7 and 8As shown, the boss 44 protrudes from one side of the insulating member 42. The boss 44 includes an end cap portion 441 and a connecting portion 442 connected in sequence. The end cap portion 441 is located at one end of the connecting portion 442 away from the main structure of the insulating member 42. The connecting portion 442 is connected between the end cap portion 441 and the main structure of the insulating member 42. That is, the root of the boss 44 is formed on the connecting portion 442. Among them, the end cap portion 441 is adapted in shape to the flared portion 431 and is fitted and connected. The connecting portion 442 is adapted in shape to the necking portion 432 and is fitted and connected.

[0051] That is to say, the shape structure of the groove 43 is adapted to the shape structure of the boss 44. The present utility model does not specifically limit the shape structure of the groove 43, as long as it can be fitted and connected with the boss 44. The groove 43 can be a circular groove, a square groove, an oval groove, etc.

[0052] In some embodiments, a plurality of grooves 43 and bosses 44 can be arranged at intervals. The number of grooves 43 and bosses 44 arranged depends on the set sizes of the metal member 41 and the insulating member 42. Exemplarily, as Figure 5 and 7 shown, three grooves 43 are arranged at intervals along the length direction on the metal member 41, and three bosses 44 are arranged at intervals along the length direction on the insulating member 42. The three grooves 43 and the three bosses 44 are arranged in one-to-one correspondence respectively.

[0053] Furthermore, in some embodiments, as Figure 1 and 2 shown, two openings 13 are provided on the housing 1. Correspondingly, two insulating seals 4 are also provided. The two insulating seals 4 are respectively plugged and arranged at the two openings 13.

[0054] More specifically, the housing 1 has opposite first end 11 and second end 12. The two openings 13 are located at the first end 11, and the two openings 13 are arranged at intervals. The first end 11 is also provided with a liquid injection hole 14, and the liquid injection hole 14 is located between the two openings 13. The second end 12 is provided with an explosion-proof valve. In this embodiment, arranging the liquid injection hole 14 and the explosion-proof valve at opposite ends of the housing 1 can prevent the residual electrolyte at the liquid injection hole 14 from contaminating the explosion-proof valve.

[0055] Furthermore, the electrode group 2 has electrode tabs 21. The above electrode terminal 3 includes a pole column 31 and a connecting piece 32 connected to each other. Among them, one end of the pole column 31 is exposed outside the housing 1 to conduct electrical energy transmission with external components. The connecting piece 32 is located inside the housing 1. The connecting piece 32 has a connected first connecting portion and second connecting portion. The first connecting portion of the connecting piece 32 is welded to the pole column 31, and the second connecting portion of the connecting piece 32 is welded to the electrode tab 21 to realize the electrical connection between the pole column 31 and the electrode tab 21. Specifically, as Figure 2As shown, the second connecting portion of the connecting piece 32 is located at the opening 13, the tab 21 is correspondingly arranged with the second connecting portion of the connecting piece 32, and at least part of the structure of the tab 21 extends through the opening 13 and bends towards the second connecting portion of the connecting piece 32. The second connecting portion of the connecting piece 32 and the tab 21 are welded through the opening 13 by welding processes such as laser welding or ultrasonic welding to achieve the electrical connection between the two.

[0056] In some embodiments not shown, the first of the above-mentioned metal part 41 and the insulating part 42 is the insulating part 42, and the second of the metal part 41 and the insulating part 42 is the metal part 41. Specifically, a groove 43 is provided on the side of the insulating part 42 facing the metal part 41, and the above-mentioned annular rib 45 is provided at the notch of the groove 43 of the insulating part 42. A boss 44 is provided on the side of the metal part 41 facing the insulating part 42, and an annular clamping groove 46 is formed on the outer peripheral side of the boss 44, and the annular rib 45 is clamped in the annular clamping groove 46. Among them, the annular rib 45 is integrally formed on the insulating part 42, and the boss 44 is integrally formed on the metal part 41.

[0057] Although the embodiments of the present invention 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 invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A battery cell, characterized in that: include: A housing having an opening; A pole group, arranged in the shell; An electrode terminal is mounted on the housing; at least a portion of the structure of the electrode terminal is located in the housing and is electrically connected to the electrode group; the opening is configured to allow the electrical connection between the electrode terminal and the electrode group to be exposed; An insulating seal comprises a metal part and an insulating part injection-molded on one side of the metal part; the metal part is connected to the shell and blocks the opening, and the insulating part is located on the side of the metal part close to the pole group; a groove and a boss which are interlocked and connected with each other are provided between the metal part and the insulating part; the groove is provided on the first one of the metal part and the insulating part, and an annular rib is provided at the notch of the groove around the first one of the metal part and the insulating part; the boss is provided on the second one of the metal part and the insulating part, and the annular rib is clamped on the outer peripheral side of the boss.

2. The battery cell according to claim 1, characterized in that: The first one of the metal part and the insulating part is the metal part, and the second one of the metal part and the insulating part is the insulating part; the annular rib is integrally formed on the metal part, and the boss is integrally formed on the insulating part.

3. The battery cell according to claim 2, characterized in that: The thickness of the metal part is in the range of 0.6-1.6 mm; the thickness of the insulating part is in the range of 0.15-1.2 mm.

4. The battery cell according to claim 3, characterized in that: The thickness of the insulating seal is in the range of 1.2-1.8 mm.

5. The battery cell according to claim 3, characterized in that: The thickness of the annular convex rib is in the range of 0.25-0.55 mm, and the distance between the annular convex rib and the bottom wall of the groove is in the range of 0.25-0.55 mm.

6. The battery cell according to claim 5, characterized in that: In a direction perpendicular to the thickness of the annular rib, the minimum inner diameter of the annular rib is in the range of 0.35-1.2 mm.

7. The battery cell according to claim 6, characterized in that: In a direction perpendicular to the thickness of the annular rib, the minimum width of the annular rib should be greater than or equal to 0.5 mm.

8. The battery cell according to any one of claims 1 to 7, characterized in that: The opening and the insulating seal are both provided in two pieces.

9. The battery cell according to claim 8, characterized in that: The shell has a first end and a second end opposite to each other; the two openings are located at the first end, and the two openings are spaced apart from each other; the first end is also provided with a liquid injection hole, and the liquid injection hole is located between the two openings; the second end is provided with an explosion-proof valve.

10. A battery pack, characterized in that: include: At least one battery cell according to any one of claims 1 to 9.

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