Secondary battery and battery pack

Abstract

The utility model discloses a secondary battery and a battery pack, the secondary battery comprises a top cover assembly, and the top cover assembly comprises a top cover sheet, an electrode terminal and a first insulating part; the top cover sheet is provided with a through hole; the electrode terminal penetrates through the through hole; the electrode terminal comprises a first body and a flange, and the flange is connected to the peripheral side of the first body in a surrounding manner; the first insulating part is arranged around the electrode terminal and is connected between the top cover plate and the electrode terminal; the first insulating part comprises an annular first section, an annular second section and an annular third section, the first section is connected with the second section, the end, away from the first section, of the second section is connected with the third section, the first section, the second section and the third section are integrally formed and define a groove, and at least part of the flange is arranged in the groove. The first section, the second section and the third section which are integrally connected are arranged to define the groove, and the flange is arranged in the groove, so that the first insulating part is spaced between the electrode terminal and the top cover plate, and the insulation reliability of the first insulating part is ensured.

Description

Technical Field

[0001] The present application belongs to the field of battery technology, and specifically relates to a secondary battery and a battery pack. Background Art

[0002] As the main energy storage unit of power batteries, secondary batteries use a top cover assembly to encapsulate the electrode assembly in the shell, and use the poles on the top cover assembly for charging and discharging. The poles are fixed on the top cover sheet, and the two are insulated by setting an insulating member. However, the insulating member is often split, and the connection stability is not high, which will cause the risk of insulation failure during the use of the battery. Utility Model Content

[0003] Purpose of the utility model: An embodiment of the present application provides a secondary battery, aiming to solve the problem that the existing insulating parts are split and prone to the risk of insulation failure; another purpose of the embodiment of the present application is to provide a battery pack.

[0004] Technical solution: A secondary battery according to an embodiment of the present application includes a top cover assembly, wherein the top cover assembly includes:

[0005] A top cover sheet having a through hole;

[0006] An electrode terminal is inserted into the through hole; the electrode terminal comprises a first body and a flange, and the flange is connected to the outer peripheral side of the first body;

[0007] A first insulating member is arranged around the electrode terminal and connected between the top cover sheet and the electrode terminal; the first insulating member includes a first segment, a second segment and a third segment in an annular shape, the first segment is connected to the second segment, and an end of the second segment away from the first segment is connected to the third segment, the first segment, the second segment and the third segment are integrally formed and surrounded by a groove, and at least a portion of the flange is arranged in the groove.

[0008] In some embodiments, the flange has a first surface and a second surface opposite to each other, and an outer peripheral surface intersecting the first surface and the second surface, the first section is in contact with the first surface, the second section is in contact with the outer peripheral surface, and the third section is in contact with the second surface.

[0009] In some embodiments, the flange includes a first limiting portion, which is arranged on the outer peripheral surface, and the first insulating member includes a second limiting portion, which is arranged on the side of the second section facing the flange, and the first limiting portion cooperates with the second limiting portion to limit the relative rotation of the electrode terminal and the first insulating member.

[0010] In some embodiments, the top cover sheet comprises:

[0011] a second body, the through hole passing through the second body;

[0012] A support platform, arranged around the inner wall of the through hole and extending toward the central axis of the through hole;

[0013] A connecting portion, arranged around the through hole and connected to the second body, wherein the connecting portion is arranged on a side of the through hole away from the support platform;

[0014] The third limiting portion is arranged around the inner circumference of the connecting portion and extends toward the central axis of the through hole; the first insulating member is arranged between the third limiting portion and the supporting platform, and the first section is in contact with the third limiting portion, and the third section is in contact with the supporting platform.

[0015] In some embodiments, the first insulating member includes a first protrusion connected to a side of the first section facing away from the flange; a first limiting groove is provided on a side of the third limiting portion facing the first section, and the first protrusion is disposed in the first limiting groove.

[0016] In some embodiments, the first insulating member also includes a second protrusion, the second protrusion is connected to the side of the second section facing away from the flange, and the first protrusion is connected to the second protrusion; a second limiting groove is provided on the side of the connecting portion facing the second section, the second limiting groove extends along the inner wall of the through hole to the support platform, the second limiting groove is connected to the first limiting groove, and the second protrusion is arranged in the second limiting groove.

[0017] In some embodiments, the first protrusion and the second protrusion are connected to form a fourth limiting portion, there are at least two fourth limiting portions, and the central angle between two adjacent fourth limiting portions is α°, satisfying: 110≤α≤180.

[0018] In some embodiments, the dimension of the first protrusion extending into the first limiting groove is a mm, satisfying: 0.1≤a≤0.5.

[0019] In some embodiments, the top cover assembly further includes a seal, which is disposed around the first body and at least partially located between the first body and the support platform.

[0020] In some embodiments, the top cover assembly also includes a second insulating member, a portion of which is covered on the outer peripheral side of the connecting portion and the third limiting portion and is arranged around the first body; a portion of the second insulating member is spaced between the third limiting portion and the first section and the first body.

[0021] Accordingly, a battery pack described in an embodiment of the present application includes a secondary battery as described in any one of the aforementioned embodiments.

[0022] Beneficial effect: Compared with the prior art, a secondary battery in an embodiment of the present application includes a top cover assembly, the top cover assembly includes a top cover sheet, an electrode terminal and a first insulating member; the top cover sheet has a through hole; the electrode terminal is inserted into the through hole; the electrode terminal includes a first body and a flange, the flange is connected around the outer peripheral side of the first body; the first insulating member is arranged around the electrode terminal and connected between the top cover sheet and the electrode terminal; the first insulating member includes a first segment, a second segment and a third segment in an annular shape, the first segment is connected to the second segment, the second segment is connected to the third segment at one end away from the first segment, the first segment, the second segment and the third segment are integrally formed and surrounded by a groove, and at least part of the flange is arranged in the groove. The present application arranges the first segment, the second segment and the third segment to form a groove, and places the flange of the electrode terminal in the groove, so that the flange of the electrode terminal is wrapped by three sides of the first insulating member, so that the first insulating member is spaced between the electrode terminal and the top cover sheet from three directions, so as to achieve a better insulation effect and ensure the insulation reliability of the first insulating member.

[0023] Compared with the prior art, a battery pack according to an embodiment of the present application includes a secondary battery according to any one of the above embodiments. It is understandable that the battery pack according to the embodiment of the present application has all the technical features and technical effects of the above secondary batteries, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 is a schematic diagram of the overall structure of a secondary battery in an embodiment of the present application;

[0026] Figure 2 is an exploded diagram of a secondary battery according to an embodiment of the present application;

[0027] Figure 3 is a structural schematic diagram of a top cover assembly according to an embodiment of the present application;

[0028] Figure 4 is an exploded view of a top cover assembly according to an embodiment of the present application;

[0029] Figure 5 is a cross-sectional view of a top cover assembly according to an embodiment of the present application;

[0030] Figure 6is a schematic diagram of the overall structure of the top cover sheet of an embodiment of the present application;

[0031] Figure 7 is a cross-sectional view of a top cover sheet according to an embodiment of the present application;

[0032] Figure 8 is a schematic structural diagram of an electrode terminal of an embodiment of the present application after being connected to a first insulating member;

[0033] Fig. 9 is a cross-sectional view of an electrode terminal of an embodiment of the present application after being connected to a first insulating member;

[0034] Fig.10 is a schematic diagram of the overall structure of the first insulating member in an embodiment of the present application;

[0035] Fig.11 is a schematic diagram of the overall structure of the first insulating member of the embodiment of the present application from another perspective;

[0036] Fig.12 is a top view of a first insulating member of an embodiment of the present application;

[0037] Fig.13 is a partial enlarged view of the top cover assembly of the embodiment of the present application;

[0038] Fig.14 is a top view of an electrode terminal according to an embodiment of the present application;

[0039] Fig.15 is a schematic structural diagram of a top cover assembly of a second embodiment of the present application;

[0040] Fig.16 is an exploded view of the top cover assembly of the second embodiment of the present application;

[0041] Fig.17 It is a cross-sectional view of the top cover assembly of the second embodiment of the present application.

[0042] 1. A cover plate; 2. A through hole; 3. A support platform; 4. A connection portion; 5. A third limit portion; 6. A first limit groove; 7. A second limit groove; 8. A second main body; 9. An electrode terminal; 10. A first main body; 11. A flange; 12. A first surface; 13. A second surface; 14. A third limit portion; 15. A fourth limit portion; 16. A seal; 17. A second seal; 18. A second seal; 19. A second seal; 20. A housing; 21. A second housing; 22. A flange; 22. A first surface; 22. A second surface; 22. A peripheral surface; 22. A first limit portion; 3. A first insulating member; 31. A first section; 32. A second section; 33. A third section; 34. A groove; 35. A second limit portion; 36. A first protrusion; 37. A second protrusion; 38. A fourth limit portion; 4. A seal; 5. A second insulating member; 200. A housing; 210. A housing; 300. An electrode assembly. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0044] In the description of the present application, it should be understood that the terms "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of the present application, "multiple" means two or more, and at least one means one, two or more, unless otherwise clearly and specifically defined. In the description of this application, "vertical" means completely vertical at 90° or almost completely vertical, for example, an angle within the range of 80° to 100° is considered vertical. Similarly, "parallel" means completely parallel or almost completely parallel, for example, an angle within 10° of completely parallel is considered parallel.

[0045] The applicant has noticed that in the field of power batteries, with the continuous development of battery application scenarios, the working conditions have become more complex, and the insulation requirements for secondary battery structural parts are gradually increasing, especially the top cover assembly 100. The electrode terminal 2 of the top cover assembly 100 is connected to the pole ear of the electrode assembly 300, which is the connection window between the inside and the outside of the secondary battery. At the same time, the outer shell 200 of the secondary battery and the top cover sheet 1 of the top cover assembly 100 are usually made of aluminum. Ensuring the insulation reliability between the electrode terminal 2 and the top cover sheet 1 is crucial to the safety of the entire secondary battery. In the existing secondary battery solution, the electrode terminal 2 is usually made of an insulating shell 200 on the upper and lower sides, respectively, and then assembled and wrapped to form an insulating part. The insulating part is spaced between the top cover sheet 1 and the electrode terminal 2 to achieve the insulation effect between the electrode terminal 2 and the top cover sheet 1. However, this split insulating part is prone to unstable connection during the use of the secondary battery, resulting in poor insulation effect or direct insulation failure.

[0046] In view of this, an embodiment of the present application provides a secondary battery, aiming to solve the problem of unstable insulation effect between the electrode terminal 2 and the top cover sheet 1 .

[0047] Please refer to Figure 1 , Figure 2 , Fig. 9 An embodiment of the present application provides a secondary battery, including a shell, an electrode assembly 300 and a top cover assembly 100 , the shell has a receiving cavity 210 , the electrode assembly 300 is disposed in the receiving cavity 210 , and the top cover assembly 100 is connected to the shell and covers the receiving cavity 210 . The top cover assembly 100 includes a top cover sheet 1, an electrode terminal 2 and a first insulating member 3; the top cover sheet 1 has a through hole 11; the electrode terminal 2 is inserted into the through hole 11; the electrode terminal 2 includes a first body 21 and a flange 22, and the flange 22 is connected to the outer peripheral side of the first body 21; the first insulating member 3 is arranged around the electrode terminal 2 and connected between the top cover sheet 1 and the electrode terminal 2; the first insulating member 3 includes a first section 31, a second section 32 and a third section 33 in an annular shape, the first section 31 is connected to the second section 32, and the end of the second section 32 away from the first section 31 is connected to the third section 33, the first section 31, the second section 32 and the third section 33 are integrally formed and surrounded by a groove 34, that is, the first section 31 and the third section 33 are bent relative to the second section 32, and the bending direction is the same, so that the groove 34 is formed, and at least part of the flange 22 is arranged in the groove 34.

[0048] In the embodiment of the present application, the first section 31, the second section 32 and the third section 33 are integrally connected to form a groove 34, and the flange 22 of the electrode terminal 2 is placed in the groove 34, so that the flange 22 of the electrode terminal 2 is wrapped by the three sides of the first insulating member 3. In this way, the first insulating member 3 is spaced between the electrode terminal 2 and the top cover sheet 1 from three directions, thereby achieving a better insulation effect and ensuring the insulation reliability of the first insulating member 3.

[0049] In some embodiments, the flange 22 has a first surface 221 and a second surface 222 opposite to each other, and an outer peripheral surface 223 intersecting the first surface 221 and the second surface 222 , the first section 31 is in contact with the first surface 221 , the second section 32 is in contact with the outer peripheral surface 223 , and the third section 33 is in contact with the second surface 222 .

[0050] In the embodiment of the present application, the first surface 221 and the second surface 222 are arranged relative to each other along the direction of the electrode assembly 300 toward the top cover assembly 100; the first surface 221 is in contact with the first section 31, and the first section 31 is arranged on the side of the flange 22 away from the electrode assembly 300; the second section 32 is in contact with the outer peripheral surface 223, and the second section 32 is arranged around the flange 22; the third section 33 is in contact with the second surface 222, and the third section 33 is arranged on the side of the flange 22 facing the electrode assembly 300; in this way, the first section 31, the second section 32 and the third section 33 wrap the flange 22 from three sides. In addition, the flange 22 is arranged around the first body 21 and connected to the first body 21. At this time, it is equivalent to that the flange 22 has only four side surfaces, three of which are respectively wrapped and protected by the three sections of the first insulating member 3, and the inner peripheral surface faces the first body 21 and is connected to the first body 21. Therefore, the flange 22 has only three side surfaces, namely the first surface 221, the second surface 222 and the outer peripheral surface 223, facing outward, and these three side surfaces are wrapped by the first insulating member 3. Therefore, the first insulating member 3 can be completely spaced between the flange 22 and the top cover sheet 1, thereby avoiding the contact between the flange 22 and the top cover sheet 1. At the same time, the first section 31, the second section 32 and the third section 33 are connected in sequence in an integral manner. When the first insulating member 3 is spaced between the electrode terminal 2 and the top cover sheet 1, the connection between the first section 31, the second section 32 and the third section 33 can be effectively prevented from being loosened, thereby maintaining the insulation effectiveness of the first insulating member 3 being spaced between the electrode terminal 2 and the top cover sheet 1. At the same time, when the surfaces of the first insulating member 3 and the flange 22 are in contact with each other, the contact between the first insulating member 3 and the flange 22 can be improved, and the possibility of displacement of the first insulating member 3 can be reduced.

[0051] In some embodiments, the flange 22 includes a first limiting portion 224, which is disposed on the outer peripheral surface 223, and the first insulating member 3 includes a second limiting portion 35, which is disposed on the side of the second section 32 facing the flange 22, and the first limiting portion 224 cooperates with the second limiting portion 35 to limit the relative rotation of the electrode terminal 2 and the first insulating member 3.

[0052] In the embodiment of the present application, the first limiting portion 224 and the second limiting portion 35 are provided to cooperate with each other so as to limit each other, thereby limiting the relative rotation between the electrode terminal 2 and the first insulating member 3, thereby effectively preventing the torsional movement of the electrode terminal 2 during use and ensuring the stability of the fixation of the electrode terminal 2.

[0053] Specifically, Fig.10 , Fig.11 and Fig.14As shown, the side surfaces of the first limiting portion 224 and the second limiting portion 35 opposite to each other may be planes, and in this case, the first limiting portion 224 and the second limiting portion 35 are in plane contact and fit, and when the electrode terminal 2 is subjected to a torsional force, the second limiting portion 35 and the first limiting portion 224 stop against each other, effectively preventing the electrode terminal 2 from rotating circumferentially in the first insulating member 3. Of course, the first limiting portion 224 may also be a groove 34 sunken toward the first body 21, and the second limiting portion 35 may be a protrusion protruding toward the flange 22, and the protrusion is placed in the groove 34 to achieve limit stop.

[0054] In some embodiments, the top cover sheet 1 includes a second body 15, a support platform 12, a connecting portion 13 and a third limiting portion 14; the through hole 11 passes through the second body 15; the support platform 12 is arranged around the inner wall of the through hole 11 and extends to the central axis of the through hole 11; the connecting portion 13 is arranged around the through hole 11 and connected to the second body 15, and the connecting portion 13 is arranged on the side of the through hole 11 away from the support platform 12; the third limiting portion 14 is arranged around the inner circumference of the connecting portion 13 and extends to the central axis of the through hole 11; the first insulating member 3 is arranged between the third limiting portion 14 and the support platform 12, and the first section 31 is in contact with the third limiting portion 14, and the third section 33 is in contact with the support platform 12.

[0055] In this embodiment, the support platform 12, the inner wall of the through hole 11, the connecting portion 13 and the third limiting portion 14 are used to wrap the first insulating member 3, and at the same time, the top cover sheet 1 is used to limit the three sides of the first insulating member 3, thereby improving the limiting effect of the top cover sheet 1 on the combination of the electrode terminal 2 and the first insulating member 3, and improving the fixing effect of the electrode terminal 2 on the top cover sheet 1.

[0056] Specifically, the first insulating member 3 of the embodiment of the present application is arranged between the first limiting portion 224 and the support platform 12, and the flange 22 of the electrode terminal 2 is arranged between the first section 31 and the third section 33 of the first insulating member 3, so the flange 22 is also between the third limiting portion 14 of the fiber pile and the support platform 12. The support platform 12 is fitted with the third section 33, and the first insulating member 3 and the flange 22 are supported in the through hole 11 by the support platform 12 to prevent the electrode terminal 2 and the first insulating member 3 from falling into the accommodating cavity 210. At the same time, the support platform 12 is also fitted with the first insulating member 3 to seal the through hole 11, thereby achieving the sealing of the top cover sheet 1. The connecting portion 13 protects the first insulating member 3 from the outer peripheral side of the second section 32, and the third connecting portion 13 is arranged on the side of the first section 31 away from the support platform 12, and is used to limit the first insulating member 3 and the electrode terminal 2 in the direction of the electrode assembly 300 toward the top cover assembly 100, and is used to confine the electrode terminal 2 and the first insulating member 3 in the through hole 11 of the top cover sheet 1, so as to fix the electrode terminal 2 and the first insulating member 3.

[0057] It should be noted that the support platform 12, the inner wall of the through hole 11, the connecting portion 13 and the third limiting portion 14 cooperate with each other to limit and surround the first insulating member 3 for protection, providing an accommodation space for the first insulating member 3, thereby effectively preventing the first insulating member 3 from being squeezed or damaged during the use of the secondary battery, thereby ensuring that the first insulating member 3 continues to maintain a good insulating state.

[0058] In addition, it should be noted that the first section 31 is arranged between the third limiting portion 14 and the flange 22. Preferably, the first section 31 is respectively fitted with the first surface 221 of the flange 22 and the third limiting portion 14, the second section 32 is respectively fitted with the outer peripheral surface 223 of the flange 22 and the inner wall and connecting portion 13 of the through hole 11, and the third section 33 is respectively fitted with the second surface 222 of the flange 22 and the support platform 12, thereby realizing the limiting fixation of the first insulating part 3 and preventing the first insulating part 3 from shaking between the third limiting portion 14 and the support platform 12, which is more conducive to maintaining the stability of the structure of the first insulating part 3, and then ensuring the insulation performance of the first insulating part 3.

[0059] like Figure 6-Figure 8 , Figure 10-11 As shown, in some embodiments, the first insulating member 3 includes a first protrusion 36, which is connected to the side of the first section 31 facing away from the flange 22; the third limiting portion 14 is provided with a first limiting groove 141 on the side facing the first section 31, and the first protrusion 36 is arranged in the first limiting groove 141.

[0060] In the embodiment of the present application, the first protrusion 36 and the first limiting groove 141 cooperate with each other to prevent the first insulating member 3 from rotating circumferentially between the third limiting portion 14 and the support platform 12, thereby ensuring the fixing stability of the electrode terminal 2.

[0061] Further, such as Figure 6-Figure 8 , Figure 10-11 As shown, in some embodiments, the first insulating member 3 also includes a second protrusion 37, the second protrusion 37 is connected to the side of the second section 32 facing away from the flange 22, and the first protrusion 36 is connected to the second protrusion 37; a second limiting groove 142 is provided on the side of the connecting portion 13 facing the second section 32, the second limiting groove 142 extends along the inner wall of the through hole 11 to the support platform 12, the second limiting groove 142 is connected to the first limiting groove 141, and the second protrusion 37 is arranged in the second limiting groove 142.

[0062] In the embodiment of the present application, a second protrusion 37 is provided to be connected with the first protrusion 36 to form an L-shaped fourth limiting portion 38, and a second limiting groove 142 is provided to be connected with the first limiting groove 141 to form an L-shaped limiting groove. At this time, the coverage of the limiting portion and the limiting groove is increased, thereby further improving the limiting effect, and being able to provide greater anti-torsion force, thereby more effectively rotating the first insulating member 3 and maintaining the stability of the first insulating member 3 fixed on the top cover sheet 1.

[0063] It should be noted that the first protrusion 36 and the second protrusion 37 are integrally connected, which is equivalent to adding an L-shaped reinforcement rib to the outer wall of the first insulating member 3, further improving the structural strength of the integrated first insulating member 3, ensuring its structural stability is not destroyed, thereby ensuring its insulation effect.

[0064] like Fig.12 As shown, in some embodiments, the first protrusion 36 and the second protrusion 37 are connected to form a fourth limiting portion 38, there are at least two fourth limiting portions 38, and the central angle between two adjacent fourth limiting portions 38 is α°, satisfying: 110≤α≤180.

[0065] In the embodiment of the present application, the fourth limit portion 38 cooperates with the first limit groove 141 and the second limit groove 142 to stop rotation, wherein the number of the fourth limit portions 38 is preferably 2 or more, wherein the angle between the two fourth limit portions 38 is between 110°-180°, and while achieving the goal of anti-twist, the number of the fourth limit portions 38 is as small as possible, preferably two, so as to facilitate the production and processing of the fourth limit portion 38 and the first limit groove 141 and the second limit groove 142.

[0066] Of course, it should be noted that the value of the angle between two adjacent fourth limiting portions 38 in the embodiment of the present application can also be any value among 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180 or a range between any two values. And the angle can be directly measured using an angle measuring tool.

[0067] Some specific embodiments of the present application are as follows:

[0068]

[0069] It should be noted that in the embodiment of the present application, when the angle between two adjacent fourth limiting portions 38 is larger (the total angle range is between 0-180 degrees), setting it at 110°-180° is convenient for processing and manufacturing, and the force is more uniform. An angle less than 110° will interfere with the manufacturing mold, and the mold cannot be used for batch production, which significantly increases the production cost.

[0070] like Fig.13 As shown, in some embodiments, the dimension of the first protrusion 36 extending into the first limiting groove 141 is a mm, satisfying: 0.1≤a≤0.5.

[0071] In the embodiment of the present application, the dimension of the first protrusion 36 extending into the first limiting groove 141 is set between 0.1-0.5 mm, which can ensure sufficient torque and ensure that the connecting portion 13 and the third limiting portion 14 of the top cover sheet 1 are not too thin to affect the fixing strength of the electrode terminal 2.

[0072] Specifically, the dimension of the first protrusion 36 of the embodiment of the present invention extending into the first limiting groove 141 can be any value among 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5 or a range between any two values. The dimension can be directly measured using a length dimension measuring tool such as a vernier caliper.

[0073] Some specific embodiments of the present application are as follows:

[0074]

[0075] It can be seen from the above embodiment that, on the basis of the thickness of the third limiting portion 14 being unchanged, the larger the dimension of the first protrusion 36 extending into the first limiting groove 141, the deeper the depth of the first limiting groove 141, and the greater the torque it can withstand, and the smaller the thrust it can withstand. Therefore, in order to maintain reasonable anti-thrust and anti-torsion strength, the embodiment of the present application selects the dimension range of the first protrusion 36 extending into the first limiting groove 141 to be 0.1≤a≤0.5.

[0076] The torque measurement method is: fix the top cover with the torque machine at the lower end, fix the electrode terminal 2 at the upper end, perform the torsion test at a speed of 20° / min until it is broken, and record the maximum torque. The thrust measurement method is: fix the top cover with the tensile machine, and for the φ16 electrode terminal 2, push the pole with a φ16 pusher until it is broken, and record the maximum force during the process.

[0077] In some embodiments, the top cover assembly 100 further includes a seal 4 , which is disposed around the first body 21 , and the seal 4 is at least partially located between the first body 21 and the support platform 12 .

[0078] In the embodiment of the present application, a seal 4 is provided to seal the gap between the electrode terminal 2 and the top cover sheet 1 . The sealing effect of the Baocheng top cover assembly 100 prevents the electrolyte from overflowing from around the electrode terminal 2 .

[0079] It should be noted that at least part of the seal 4 is located between the first body 21 and the support platform 12, which prevents the first body 21 from short-circuiting the support platform 12 and ensures the insulation between the first body 21 and the support platform 12. The seal 4 may also be partially located between the flange 22 and the support platform 12, in which case the seal 4 is further used to be spaced between the flange 22 and the support platform 12, further avoiding contact between the support platform 12 and the flange 22, thereby improving the insulation effect.

[0080] like Figure 15-17 As shown, in some embodiments, the top cover assembly 100 also includes a second insulating member 5, a portion of the second insulating member 5 is disposed on the outer peripheral side of the connecting portion 13 and the third limiting portion 14 and is disposed around the first body 21; a portion of the second insulating member 5 is disposed at intervals between the third limiting portion 14 and the first section 31 and the first body 21.

[0081] In the embodiment of the present application, the second insulating member 5 may or may not be provided outside the connecting portion 13 and the third limiting portion 14, because the first insulating member 3 has played a good role in insulating the electrode terminal 2 and the top cover sheet 1. When the second insulating member 5 is not provided, insulating materials can be saved and the overall cost of the battery can be reduced.

[0082] In the embodiment of the present application, a second insulating member 5 can also be provided on the outside of the connecting portion 13 and the third limiting portion 14. At this time, the second insulating member 5 is not only wrapped around the outside of the connecting portion 13 and the third limiting portion 14, but part of the second insulating member 5 fills the gap between the first body 21 and the third connecting portion 13 and the second insulating member 5, thereby further ensuring the insulation effect, and at the same time being able to ensure the creepage distance, thereby ensuring the insulation effect between the electrode terminal 2 and the top cover sheet 1.

[0083] Accordingly, a battery pack according to an embodiment of the present application includes a secondary battery as described in any one of the aforementioned embodiments.

[0084] It can be understood that the battery pack of the embodiment of the present application has all the technical features and technical effects of the aforementioned secondary battery, which will not be described in detail here.

[0085] It should be noted that the battery pack of the embodiment itself can be used for backup power supply, electrodes, electric vehicles, electric bicycles, electric motorcycles, large batteries, etc.

[0086] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0087] The above is a detailed introduction to a secondary battery and a battery pack provided in the embodiments of the present application, and specific examples are used to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the technical solution and its core idea of ​​the present application; ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the present application.

Claims

1. A secondary battery, characterized in that: A top cover assembly is included, the top cover assembly comprising: A top cover sheet having a through hole; An electrode terminal is inserted into the through hole; the electrode terminal comprises a first body and a flange, and the flange is connected to the outer peripheral side of the first body; A first insulating member is arranged around the electrode terminal and connected between the top cover sheet and the electrode terminal; the first insulating member includes a first segment, a second segment and a third segment in an annular shape, the first segment is connected to the second segment, and an end of the second segment away from the first segment is connected to the third segment, the first segment, the second segment and the third segment are integrally formed and surrounded by a groove, and at least a portion of the flange is arranged in the groove.

2. The secondary battery according to claim 1, characterized in that: The flange has a first surface and a second surface facing each other, and an outer peripheral surface intersecting the first surface and the second surface. The first section is in contact with the first surface, the second section is in contact with the outer peripheral surface, and the third section is in contact with the second surface.

3. The secondary battery according to claim 2, characterized in that: The flange includes a first limiting portion, which is arranged on the outer peripheral surface; the first insulating member includes a second limiting portion, which is arranged on the side of the second section facing the flange; the first limiting portion cooperates with the second limiting portion to limit the relative rotation of the electrode terminal and the first insulating member.

4. The secondary battery according to claim 2, characterized in that: The top cover sheet comprises: a second body, the through hole passing through the second body; A support platform, arranged around the inner wall of the through hole and extending toward the central axis of the through hole; A connecting portion, arranged around the through hole and connected to the second body, wherein the connecting portion is arranged on a side of the through hole away from the support platform; The third limiting portion is arranged around the inner circumference of the connecting portion and extends toward the central axis of the through hole; the first insulating member is arranged between the third limiting portion and the supporting platform, and the first section is in contact with the third limiting portion, and the third section is in contact with the supporting platform.

5. The secondary battery according to claim 4, characterized in that: The first insulating member includes a first protrusion connected to a side of the first section away from the flange; a first limiting groove is provided on a side of the third limiting portion facing the first section, and the first protrusion is arranged in the first limiting groove.

6. The secondary battery according to claim 5, characterized in that: The first insulating member also includes a second protrusion, which is connected to the side of the second section facing away from the flange, and the first protrusion is connected to the second protrusion; a second limiting groove is provided on the side of the connecting portion facing the second section, and the second limiting groove extends along the inner wall of the through hole to the support platform, the second limiting groove is connected to the first limiting groove, and the second protrusion is arranged in the second limiting groove.

7. The secondary battery according to claim 6, characterized in that: The first protrusion and the second protrusion are connected to form a fourth limiting portion. There are at least two fourth limiting portions. The central angle between two adjacent fourth limiting portions is α°, satisfying: 110≤α≤180.

8. The secondary battery according to claim 5, characterized in that: The dimension of the first protrusion extending into the first limiting groove is a mm, satisfying: 0.1≤a≤0.

5.

9. The secondary battery according to claim 4, characterized in that: The top cover assembly further includes a sealing member, which is disposed around the first body and at least partially located between the first body and the support platform.

10. The secondary battery according to claim 9, characterized in that: The top cover assembly also includes a second insulating member, a portion of which is covered on the outer peripheral side of the connecting portion and the third limiting portion and is arranged around the first body; a portion of the second insulating member is arranged at intervals between the third limiting portion and the first section and the first body.

11. A battery pack, characterized in that: Comprising the secondary battery as claimed in any one of claims 1 to 10.

Images