Top cover assembly, energy storage device and power utilization system

Abstract

The invention discloses a top cover assembly, an energy storage device and a power utilization system. The top cover assembly comprises a top cover, a lower insulating part, a pole, a sealing part, a pressing ring and a heat insulation part, wherein the top cover is provided with a first through hole; the lower insulating part comprises a first surface, a second surface and a second through hole, the first surface abuts against the top cover, and the second through hole corresponds to the first through hole in position; the second end of the pole sequentially penetrates through the first through hole and the second through hole, and the first end extends along the radial direction of the pole to form a flange; the sealing element is sleeved on the peripheral surface of the post terminal and is positioned between the top cover and the flange along the axial direction of the post terminal; the pressing ring is welded to the second end. The heat insulation piece comprises a body, at least one first supporting part and a third through hole, the body is arranged on the peripheral face of the pole in a sleeving mode through the third through hole and arranged between the second surface and the pressing ring in the axial direction of the pole, and the first supporting part is arranged on the face, facing the second surface, of the body and abuts against the second surface; and a gap is formed between the body and the second surface along the axial direction of the pole.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a top cover assembly, an energy storage device and an electricity system. Background Art

[0002] Rechargeable batteries are also called rechargeable batteries or storage batteries. During their manufacturing process, the poles and pressure rings in the top cover assembly are laser welded, wherein the pressure ring is generally made of metal, and the poles and the pressure rings are generally welded by metal.

[0003] However, the melting points of the pole and the pressure ring are usually high, and a large amount of heat will be generated during the welding process. In addition, the pole and the pressure ring have good thermal conductivity, which can easily transfer a large amount of heat to the lower insulating part, causing the lower insulating part to melt due to heat, thereby causing the seal to fail to be compressed into place and the seal to fail, causing safety hazards to the secondary battery. Summary of the invention

[0004] The present application discloses a top cover assembly, an energy storage device and an electric system. The top cover assembly can effectively reduce the probability of the lower insulating member being melted by heat when the pressure ring is welded to the pole, which is beneficial to improving the safety performance of the secondary battery.

[0005] In order to achieve the above objectives, in a first aspect, the present application discloses a top cover assembly, comprising:

[0006] A top cover, wherein the top cover has a first through hole;

[0007] A lower insulating member, the lower insulating member comprising a first surface and a second surface opposite to each other, and a second through hole penetrating the first surface and the second surface, the first surface abuts against the top cover, and the second through hole corresponds to the position of the first through hole;

[0008] A pole, the pole having a first end and a second end, the second end sequentially passing through the first through hole and the second through hole, the first end extending along the radial direction of the pole to form a flange;

[0009] A sealing member, the sealing member is sleeved on the outer peripheral surface of the pole and is located between a surface of the top cover away from the first surface and the flange along the axial direction of the pole;

[0010] a pressure ring welded to the second end; and

[0011] A heat insulating member, comprising a main body, at least one first supporting portion and a third through hole, wherein the main body is sleeved on the outer circumferential surface of the pole through the third through hole, and is arranged between the second surface and the pressure ring along the axial direction of the pole, the first supporting portion is arranged on a side of the main body facing the second surface, and the first supporting portion abuts against the second surface, so that a gap is formed between the main body and the second surface along the axial direction of the pole.

[0012] In this embodiment, by setting the main body of the axial heat insulation member between the second surface and the pressure ring along the pole, the heat transferred from the pressure ring to the lower insulating member is effectively reduced, and the probability of the lower insulating member melting due to heat when welding the pressure ring is reduced, thereby reducing the probability of the sealing member not being compressed into place due to the melting of the lower insulating member due to heat, thereby improving the safety performance of the secondary battery.

[0013] The first support portion is arranged on the side of the main body facing the second surface, and the first support portion abuts against the second surface, so that a gap is formed between the main body and the second surface along the axial direction of the pole, so that an air insulation layer can be formed between the main body and the second surface of the lower insulating member, further reducing the heat transferred from the pressure ring to the lower insulating member, further reducing the probability of the lower insulating member melting due to heat, and improving the safety performance of the secondary battery.

[0014] In some implementations, the first support portion includes a support ring, and the support ring is disposed on a surface of the body facing the second surface along a circumferential direction of the third through hole.

[0015] Thus, the structure of the first supporting part can be made simpler and easier to implement.

[0016] In some implementations, the support ring includes a first sub-support ring and a second sub-support ring that are coaxially arranged, and the first sub-support ring and the second sub-support ring are arranged on a surface of the body facing the second surface at intervals along the radial direction of the pole.

[0017] Therefore, when the main body of the thermal insulation member is squeezed, each part of the main body can be supported by the first support portion and is less likely to become skewed, thereby enabling each part of the main body and the lower insulating member to form an air insulation layer.

[0018] In some implementations, the first sub-support ring is disposed close to the third through hole, and the second sub-support ring is disposed close to the outer peripheral edge of the body.

[0019] As a result, the edge of the main body close to the third through hole and the outer edge are not easily deformed when subjected to pressure, so that the insulation effects of the air insulation layer formed by the edge of the main body and the lower insulating member, and the air insulation layer formed by other parts of the main body and the lower insulating member are basically consistent, further reducing the probability of the lower insulating member being heated and melted due to pressure ring welding.

[0020] In some implementations, the first support portion includes a plurality of first support protrusions, and the plurality of first support protrusions are arranged at intervals along the circumference of the body on a surface of the body facing the second surface.

[0021] Thus, a gap can be provided between the larger area of ​​the body and the lower insulating member, further reducing the probability of the lower insulating member melting due to heat, thereby improving the safety performance of the secondary battery.

[0022] In some implementations, a protrusion extends from an edge of the second through hole toward the top cover, and along the radial direction of the pole, the protrusion is located between the outer circumferential surface of the pole and the hole wall of the first through hole.

[0023] Thus, the pole and the top cover can be insulated by the protrusion. Compared with setting the seal between the outer peripheral surface of the pole and the hole wall of the first through hole, the protrusion is not easy to be distorted during the assembly of the top cover assembly, so that the insulation reliability between the pole and the top cover is better, and the safety performance of the secondary battery is improved.

[0024] In some implementations, along the axial direction of the pole, the seal is at least partially opposite to the protrusion and has a first interval with the protrusion.

[0025] In this way, it can effectively prevent the lower insulating part from squeezing the thermal insulation part with a large force due to the seal squeezing the protrusion with a large force, and avoid more heat being transferred to the lower insulating part due to the lower insulating part squeezing the thermal insulation part with a large force, thereby effectively reducing the risk of the lower insulating part melting due to heat, and further improving the safety performance of the secondary battery.

[0026] In some implementations, along the axial direction of the pole, the protrusion is lower than the surface where the top cover abuts against the seal, so that the first interval is formed between the protrusion and the seal, and / or,

[0027] Along the axial direction of the pole, the sealing member is provided with a first groove at a position corresponding to the protruding portion, so that the first gap is formed between the protruding portion and a groove bottom wall of the first groove.

[0028] Thus, the implementation of the first interval can be simple and easy to implement.

[0029] In some implementations, a first thermal insulation layer is applied to a surface of the flange that abuts against the seal, and a projection of the seal on the flange along the axial direction of the pole is located on the first thermal insulation layer.

[0030] Thus, the first thermal insulation layer can reduce the heat transferred from the pole to the seal, effectively reducing the possibility of heat damage to the seal and improving the airtightness of the top cover assembly, so that the secondary battery assembled with the top cover assembly can still have good sealing, thereby making the secondary battery have better safety performance.

[0031] In some implementations, the thickness of the first thermal insulation layer is 50 um to 200 um.

[0032] Therefore, the thickness of the first heat insulation layer is between 50um and 200um, which can make the seal have better sealing performance and better heat insulation effect.

[0033] In some implementations, at least one avoidance hole is provided on the lower insulating member;

[0034] At least one second supporting portion is further provided on a surface of the main body facing the lower insulating member. The second supporting portion is penetrated through the avoidance hole and abuts against the second surface of the top cover.

[0035] Thus, the distance between the pressure ring and the top cover can be separated by the heat insulating member, so that even if the lower insulating member is heated, melted and thinned, the heat insulating member can still prevent the pressure ring from being pressed too much in the direction close to the top cover, thereby making the step height difference between the pressure ring and the pole meet the requirements, preventing the connection piece from arching and deforming during subsequent welding of the connection piece, and effectively improving the performance of the secondary battery.

[0036] In some implementations, the second support portion includes a plurality of second support protrusions, and the plurality of second support protrusions are arranged at intervals along the circumference of the body on a surface of the body facing the second surface.

[0037] Thus, the structure of the second supporting portion can be made simpler and easier to implement.

[0038] In some implementations, a groove is provided on the second surface, the pressure ring is at least partially accommodated in the groove, the thermal insulation member is located between the bottom wall of the groove and the pressure ring, the outer peripheral surface of the pressure ring corresponds to the groove side wall of the groove along the radial direction of the pole, the outer peripheral edge of the pressure ring is provided with a first chamfer, and the groove side wall of the groove is provided with a second groove to form a second gap between at least a portion of the groove side wall and the outer peripheral surface of the pressure ring.

[0039] Therefore, by providing a first chamfer on the peripheral edge of the pressure ring and providing a second groove on the side wall of the groove, a second gap is formed between at least a portion of the side wall and the peripheral surface of the pressure ring, which can effectively reduce the contact area between the pressure ring and the side wall of the groove, thereby effectively reducing the heat transferred from the peripheral surface of the pressure ring to the lower insulating member, further reducing the probability of the lower insulating member melting due to heat, thereby improving the safety performance of the secondary battery.

[0040] In some implementations, a second thermal insulation layer is coated on the sidewalls of the groove.

[0041] As a result, less heat can be transferred from the outer peripheral surface of the pressure ring to the lower insulating member, thereby reducing the probability of the lower insulating member melting due to heat, thereby improving the safety performance of the secondary battery.

[0042] In some implementations, the outer circumferential surface of the pole located between the flange and the pressure ring has a first planar structure, the hole wall of the second through hole has a second planar structure, the hole wall of the third through hole has a third planar structure, and the first planar structure abuts against the second planar structure and the third planar structure respectively;

[0043] The outer peripheral surface of the body has a fourth planar structure, the groove side wall of the sink groove has a fifth planar structure, and the fourth planar structure abuts against the fifth planar structure.

[0044] Thus, the torque applied to the pole can be transmitted to the top cover and the lower insulating member, and to the lower insulating member through the heat insulating member, thereby effectively improving the torsional resistance of the pole and facilitating the improvement of the performance of the secondary battery.

[0045] In some implementations, the height of the first support portion protruding from the body along the axial direction of the pole is A, and A≥0.05 mm.

[0046] As a result, a larger gap can be formed between the main body and the second surface along the axial direction of the pole, and an air insulation layer with a larger axial dimension along the pole can be formed between the main body and the second surface of the lower insulating member, thereby further reducing the heat transferred from the pressure ring to the lower insulating member, and further reducing the probability of the lower insulating member melting due to heat, thereby improving the safety performance of the secondary battery.

[0047] In a second aspect, the present application further discloses an energy storage device, comprising:

[0048] A housing, wherein the housing has a receiving cavity and an opening communicating with the receiving cavity;

[0049] A battery cell, the battery cell being accommodated in the accommodation cavity; and

[0050] The top cover assembly described in any one of the first aspects is sealed at the opening, and the pressure ring is electrically connected to the battery core.

[0051] In a third aspect, the present application further discloses an electricity consumption system, comprising the energy storage device described in the second aspect.

[0052] In this embodiment, the energy storage device of the power system is the energy storage device described in the second aspect above, so the energy storage device in this embodiment has the technical effect of the energy storage device in the second aspect above.

[0053] Compared with the prior art, the beneficial effects of this application are:

[0054] In the application, the main body of the thermal insulation member is arranged between the second surface and the pressure ring, which effectively reduces the heat transferred from the pressure ring to the lower insulating member, reduces the probability of the lower insulating member melting due to heat when welding the pressure ring, and thus reduces the probability of the sealing member not being compressed into place due to the melting of the lower insulating member due to heat, thereby improving the safety performance of the secondary battery.

[0055] The first support portion is arranged on the side of the main body facing the second surface, and the first support portion abuts against the second surface, so that a gap is formed between the main body and the second surface along the axial direction of the pole, so that an air insulation layer can be formed between the main body and the second surface of the lower insulating member, further reducing the heat transferred from the pressure ring to the lower insulating member, further reducing the probability of the lower insulating member melting due to heat, and improving the safety performance of the secondary battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0057] Figure 1 is an exploded view of a top cover assembly provided in an embodiment of the present application;

[0058] Figure 2 is a three-dimensional diagram of a top cover assembly provided in an embodiment of the present application;

[0059] Figure 3 is a cross-sectional view of a top cover assembly provided in an embodiment of the present application;

[0060] Figure 4 yes Figure 3 Enlarged view of the C position in the middle;

[0061] Figure 5 yes Figure 4The first enlarged view at the D position in the middle;

[0062] Figure 6a is a three-dimensional diagram of a thermal insulation member provided in an embodiment of the present application;

[0063] Figure 6b is a three-dimensional diagram of another thermal insulation member provided in an embodiment of the present application;

[0064] Figure 7 yes Figure 1 The enlarged image at position B in the middle;

[0065] Figure 8 yes Figure 4 The second enlarged view at the middle D position;

[0066] Fig. 9 yes Figure 4 The third enlarged view at the middle D position;

[0067] Fig.10 is an exploded diagram of an energy storage device provided in an embodiment of the present application;

[0068] Fig.11 It is a structural schematic diagram of an electricity consumption system provided in an embodiment of the present application.

[0069] Description of reference numerals:

[0070] 1-top cover; 11-first through hole; 2-lower insulating member; 21-first surface; 22-second surface; 23-second through hole; 24-protrusion; 25-avoidance hole; 26-sunk groove; 261-second groove; 3-pole; 31-first end; 32-second end; 33-flange; 4-seal; 41-first groove; 5-pressure ring; 51-first chamfer; 6-insulating member; 61-body; 62-first support portion; 621-first sub-support ring; 622-second sub-support ring; 623-first support protrusion; 63-third through hole; 64-second support portion; 8-first insulation layer; 9-upper insulating member;

[0071] 10-top cover assembly; 20-battery core; 30-housing;

[0072] 1000-power system; 100-energy storage device; 200-power conversion device; 300-power load. DETAILED DESCRIPTION

[0073] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0074] In this application, the terms "installed", "set", "provided with", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0075] In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, "plurality" means two or more.

[0076] Based on the problems in the background technology, the present application discloses a top cover assembly, an energy storage device and an electric system. The top cover assembly can effectively reduce the probability of the lower insulating member being melted by heat when the pressure ring is welded to the pole, which is beneficial to improving the safety performance of the secondary battery.

[0077] The technical solution of the present application will be further described below in conjunction with specific embodiments and drawings.

[0078] This embodiment provides a top cover assembly, such as Figure 1-6b As shown, it includes a top cover 1, a lower insulating member 2, a pole 3, a sealing member 4, a pressure ring 5 and a heat insulating member 6. Among them, the top cover 1 has a first through hole 11; the lower insulating member 2 includes a first surface 21 and a second surface 22 opposite to each other, and a second through hole 23 penetrating the first surface 21 and the second surface 22, the first surface 21 abuts against the top cover 1, and the second through hole 23 corresponds to the position of the first through hole 11; the pole 3 has a first end 31 and a second end 32, the second end 32 passes through the first through hole 11 and the second through hole 23 in sequence, and the first end 31 is radially (such as Figure 1 The seal 4 is sleeved on the outer peripheral surface of the pole 3 and extends in the axial direction of the pole 3 (such as Figure 1The first support portion 62 is disposed on the side of the body 61 facing the second surface 22, and the first support portion 62 is abutted against the second surface 22, so that a gap is formed between the body 61 and the second surface 22 along the axial direction of the pole 3.

[0079] It can be understood that the pressure ring 5 and the pole 3 can both be made of metal materials, wherein the pressure ring 5 can be at least one of metal materials such as copper, copper alloy, aluminum, aluminum alloy, etc., and the pole can also be at least one of metal materials such as copper, copper alloy, aluminum, aluminum alloy, etc. The welding between the pressure ring 5 and the pole 3 can be copper-copper welding or copper-aluminum welding, and the melting point of copper and copper alloys is usually high, so that a large amount of heat will be generated when the pressure ring 5 and the pole 3 are welded.

[0080] Therefore, by setting the main body 61 of the heat insulating member 6 between the second surface 22 and the pressure ring 5 along the axial direction of the pole 3, the heat transferred from the pressure ring 5 to the lower insulating member 2 is effectively reduced, and the probability of the lower insulating member 2 being melted due to heat when the pressure ring 5 and the pole 3 are welded is reduced, thereby reducing the probability of the sealing member 4 not being compressed into place due to the heat melting of the lower insulating member 2, thereby improving the safety performance of the secondary battery.

[0081] The first support portion 62 is arranged on the side of the main body 61 facing the second surface 22, and the first support portion 62 is in contact with the second surface 22, so that a gap is formed between the main body 61 and the second surface 22 along the axial direction of the pole 3, so that an air insulation layer can be formed between the main body 61 and the second surface 22 of the lower insulating member 2, thereby further reducing the heat transferred from the pressure ring 5 to the lower insulating member 2, and further reducing the probability of the lower insulating member 2 being melted by heat, so that the safety performance of the secondary battery is better.

[0082] The seal 4 is sleeved on the outer circumferential surface of the pole 3 and is located between the side of the top cover 1 away from the first surface 21 and the flange 33 along the axial direction of the pole 3, that is, the seal 4 is sealed between the top cover 1 and the pole 3, so that when the welding seal between the pole 3 and the pressure ring 5 fails, the sealing ring can also make the top cover assembly 10 have better airtightness, so that the secondary battery assembled with the top cover assembly 10 can still have good sealing, so that the secondary battery has better safety performance.

[0083] The heat insulating member 6 has a relatively high hardness, so that the heat insulating member 6 is not easily deformed along the axial direction of the pole 3 when being squeezed by the pressure ring 5 , which is beneficial to improving the stability of the compression amount of the seal 4 .

[0084] In addition, the material of the heat insulating member 6 can be any one of extruded polystyrene, polyetherketone, polytetrafluoroethylene, etc., which is not limited here.

[0085] The first support portion 62 may be implemented in a variety of ways. In one possible implementation, Figure 6a As shown, the first support portion 62 includes a support ring, which is arranged on a surface of the body 61 facing the second surface 22 along the circumference of the third through hole 63 .

[0086] Therefore, the structure of the first supporting portion 62 can be relatively simple and easy to implement.

[0087] The support ring may be in the shape of a circular ring, an elliptical ring, a rectangular ring, a diamond ring, a hexagonal ring, etc., and is not limited here.

[0088] The support ring includes a first sub-support ring 621 and a second sub-support ring 622 which are coaxially arranged. The first sub-support ring 621 and the second sub-support ring 622 are arranged on a surface of the body 61 facing the second surface 22 at intervals along the radial direction of the pole 3 .

[0089] Therefore, when the main body 61 of the thermal insulation component 6 is squeezed, each part of the main body 61 can be supported by the first support portion 62, and is not prone to skewing, so that each part of the main body 61 and the lower insulating component 2 can form an air insulation layer, further reducing the probability of the lower insulating component 2 being heated and melted due to the welding of the pressure ring 5.

[0090] The first sub-support ring 621 and the second sub-support ring 622 may be coaxially arranged or non-coaxially arranged, which is not limited here. The structures of the first sub-support ring 621 and the second sub-support ring 622 may be substantially the same or different, which is not limited here.

[0091] Optionally, the first sub-support ring 621 may be disposed close to the third through hole 63 , and the second sub-support ring 622 may be disposed close to the outer peripheral edge of the body 61 .

[0092] As a result, the edge of the main body 61 close to the third through hole 63 and the outer edge are not easily deformed when subjected to pressure, so that the insulation effect of the air insulation layer formed by the edge of the main body 61 and the lower insulating part 2 and the air insulation layer formed by other parts of the main body 61 and the lower insulating part 2 are basically consistent, further reducing the probability of the lower insulating part 2 being heated and melted due to the welding of the pressure ring 5.

[0093] It should be explained that the above-mentioned setting of the first sub-support ring 621 close to the third through hole 63 can be that the first sub-support ring 621 is set at the edge of the third through hole 63, or that there is a certain distance between the first sub-support ring 621 and the edge of the third through hole 63, which is not limited here.

[0094] It also needs to be explained that the above-mentioned second sub-support ring 622 is arranged close to the outer peripheral edge of the main body 61. It can be that the second sub-support ring 622 is arranged on the outer peripheral edge of the main body 61, or there is a certain distance between the second sub-support ring 622 and the outer peripheral edge of the main body 61, which is not limited here.

[0095] In another possible implementation of the first support portion 62, as Figure 6b As shown, the first support portion 62 includes a plurality of first support protrusions 623 , and the plurality of first support protrusions 623 are arranged at intervals along the circumferential direction of the body 61 on a surface of the body 61 facing the second surface 22 .

[0096] Thus, a gap can be provided between the larger area on the body 61 and the lower insulating member 2, making it more difficult for heat to be transferred from the pressure ring 5 to the lower insulating member 2, further reducing the probability of the lower insulating member 2 melting due to heat, and improving the safety performance of the secondary battery.

[0097] The first supporting protrusion 623 may be any one of a prismatic structure, a cylindrical structure, a frustum structure, etc., which is not limited here.

[0098] The number of the first supporting protrusions 623 can be two, three or more, which is not limited here.

[0099] In some embodiments, the height of the first support portion 62 protruding from the main body 61 along the axial direction of the pole 3 is A (eg Figure 5 As shown in ), A≥0.05mm.

[0100] As a result, a larger gap can be formed between the main body 61 and the second surface 22 along the axial direction of the pole 3, and an air insulation layer with a larger axial dimension along the pole 3 can be formed between the main body 61 and the second surface 22 of the lower insulating member 2, thereby further reducing the heat transferred from the pressure ring 5 to the lower insulating member 2, and further reducing the probability of the lower insulating member 2 melting due to heat, thereby improving the safety performance of the secondary battery.

[0101] The height of the first support portion 62 protruding from the main body 61 along the axial direction of the pole 3 can be 0.05 mm, 0.06 mm, 0.07 mm, etc., which is not limited here.

[0102] In other embodiments, Figure 6a and Figure 7As shown, at least one avoidance hole 25 is provided on the lower insulating member 2; at least one second support portion 64 is also provided on the surface of the body 61 facing the lower insulating member 2, and the second support portion 64 is penetrated in the avoidance hole 25 and abuts against the second surface 22 of the top cover 1.

[0103] Thus, by abutting the second support portion 64 of the heat insulating member 6 against the top cover 1, the distance between the pressure ring 5 and the top cover 1 can be further spaced by the heat insulating member 6, so that even when the lower insulating member 2 is melted and thinned by heat, the heat insulating member 6 can still prevent the pressure ring 5 from being pressed too much in the direction close to the top cover 1, thereby making the step height difference between the pressure ring 5 and the pole 3 meet the requirements, preventing the connection piece from arching and deforming during subsequent welding, and effectively improving the performance of the secondary battery.

[0104] The second supporting portion 64 includes a plurality of second supporting protrusions, and the plurality of second supporting protrusions are disposed at intervals along the circumference of the body 61 on a surface of the body 61 facing the second surface 22 .

[0105] Thus, the structure of the second support portion 64 can be relatively simple and easy to implement; and, a plurality of second support protrusions are arranged at intervals along the circumference of the main body 61 on the side of the main body 61 facing the second surface 22, so that the support of the second support portion 64 to the main body 61 can be relatively stable, thereby making it less likely for the pressure ring 5 to be pressed too much in the direction of the top cover 1.

[0106] The number of the second support protrusions may be two, three or more, which is not limited herein. For example, the number of the second support protrusions may be six, and the six second support protrusions are evenly spaced and arranged on the body 61 along the circumference of the body 61 .

[0107] In some embodiments, Figure 5 , Figure 8 and Fig. 9 As shown, a protrusion 24 extends from the edge of the second through hole 23 toward the top cover 1 , and along the radial direction of the pole 3 , the protrusion 24 is located between the outer peripheral surface of the pole 3 and the hole wall of the first through hole 11 .

[0108] Thus, the pole 3 and the top cover 1 can be insulated by the protrusion 24. Compared with the method of setting the seal 4 between the outer peripheral surface of the pole 3 and the hole wall of the first through hole 11, the protrusion 24 is not easy to be distorted during the assembly process of the top cover assembly 10, so that the insulation reliability between the pole 3 and the top cover 1 is better, the short circuit between the pole 3 and the top cover 1 is effectively reduced, and the safety performance of the secondary battery is improved.

[0109] The protrusion 24 may extend along the axial direction of the pole 3 or in a direction forming an angle with the axial direction of the pole 3 , as long as it extends toward the top cover 1 and is located between the outer peripheral surface of the pole 3 and the hole wall of the first through hole 11 along the radial direction of the pole 3 .

[0110] Alternatively, if Figure 8 and Fig. 9 As shown, along the axial direction of the pole 3, the seal 4 is at least partially opposite to the protrusion 24, and has a first interval (such as Figure 8 The spacing shown in E).

[0111] In this way, it can effectively prevent the lower insulating part 2 from squeezing the thermal insulation part 6 with a large force due to the seal 4 squeezing the protrusion 24 with a large force, and avoid more heat being transferred to the lower insulating part 2 due to the lower insulating part 2 squeezing the thermal insulation part 6 with a large force, thereby effectively reducing the risk of the lower insulating part 2 melting due to heat, and further improving the safety performance of the secondary battery.

[0112] There are many ways to implement the first interval between the seal 4 and the protrusion 24 along the axial direction of the pole 3. In one possible implementation, Figure 8 As shown, along the axial direction of the pole 3, the protrusion 24 is lower than the surface where the top cover 1 abuts against the seal 4, so that a first interval is formed between the protrusion 24 and the seal 4. Thus, the first interval can be realized in a simple and easy manner.

[0113] In another possible implementation, Fig. 9 As shown, along the axial direction of the pole 3 , the seal 4 is provided with a first groove 41 at a position corresponding to the protrusion 24 , so that a first gap is formed between the protrusion 24 and the bottom wall of the first groove 41 .

[0114] As a result, the requirement on the dimension of the protrusion 24 along the axial direction of the pole 3 is reduced, the difficulty of manufacturing the lower insulating member 2 is reduced, and the cost is reduced.

[0115] In some embodiments, Figure 5 As shown, a first heat insulation layer 8 is applied on the surface of the flange 33 that contacts the seal 4 , and the projection of the seal 4 on the flange 33 along the axial direction of the pole 3 is located on the first heat insulation layer 8 .

[0116] Thus, the first thermal insulation layer 8 can reduce the heat transferred from the pole 3 to the seal 4, effectively reducing the possibility of heat damage to the seal 4 and improving the airtightness of the top cover assembly 10, so that the secondary battery assembled with the top cover assembly 10 can still have good sealing, thereby making the secondary battery have better safety performance.

[0117] Among them, the first thermal insulation layer 8 can be fully coated on the side where the flange 33 abuts the seal 4, or the first thermal insulation layer 8 can be coated on a partial area of ​​the side where the flange 33 abuts the seal 4, as long as the projection of the seal 4 on the flange 33 along the axial direction of the pole 3 is located on the first thermal insulation layer 8, and no limitation is made here.

[0118] The first heat insulation layer 8 may be any one of UV (Ultra-Violet Ray) coating, ceramic fiber heat insulation coating, silicate heat insulation coating, etc. Preferably, the first heat insulation layer 8 may be a UV coating, which may be coated on the side where the flange 33 abuts against the seal 4 by inkjet printing, and is easy to operate and implement. The heat transfer coefficient of the UV coating may be 0.2 W / mk, and of course may be other lower heat transfer coefficients, which are not limited here.

[0119] In addition, the thickness of the first heat insulating layer 8 is 50 um to 200 um.

[0120] In this way, the thickness of the first thermal insulation layer 8 will not be too thick to affect the compression of the seal 4, nor will the thickness of the first thermal insulation layer 8 be too thin to cause more heat to be transferred from the pole 3 to the seal 4. In other words, the thickness of the first thermal insulation layer 8 is between 50um and 200um, which can make the seal 4 have better sealing and better thermal insulation effect.

[0121] The thickness of the first heat insulation layer 8 may be 50um, 100um, 150um, 200um, etc., which is not limited here.

[0122] In some embodiments, Figure 5 As shown, a recessed groove 26 is provided on the second surface 22, and the pressure ring 5 is at least partially accommodated in the recessed groove 26. The heat insulating member 6 is located between the bottom wall of the recessed groove 26 and the pressure ring 5. The outer peripheral surface of the pressure ring 5 corresponds to the groove side wall of the recessed groove 26 along the radial direction of the pole 3. The outer peripheral edge of the pressure ring 5 is provided with a first chamfer 51, and the groove side wall of the recessed groove 26 is provided with a second groove 261, so that a second gap is formed between at least a portion of the groove side wall and the outer peripheral surface of the pressure ring 5.

[0123] Thus, the size of the top cover assembly 10 along the axial direction of the pole 3 can be made smaller, so that the top cover assembly 10 can occupy a smaller space along the axial direction of the pole 3, which is beneficial to the lightweight and thin setting of the secondary battery.

[0124] Furthermore, a first chamfer 51 is provided on the peripheral edge of the pressure ring 5, and a second groove 261 is provided on the side wall of the groove 26, so that a second gap is formed between at least a portion of the side wall of the groove and the peripheral surface of the pressure ring 5, which can effectively reduce the contact area between the pressure ring 5 and the side wall of the groove 26, thereby effectively reducing the heat transferred from the peripheral surface of the pressure ring 5 to the lower insulating member 2, further reducing the probability of the lower insulating member 2 being melted by heat, thereby making the safety performance of the secondary battery better.

[0125] The chamfer angle of the first chamfer 51 can be 45°, 30°, 60°, etc., which is not limited here.

[0126] In addition, the cross-sectional shape of the second groove 261 can be any one of a triangle, a trapezoid, a rectangle, a semicircle, etc., which is not limited here.

[0127] Optionally, a second heat insulating layer may be coated on the side wall of the groove, thereby reducing the amount of heat transferred from the outer circumference of the pressure ring 5 to the lower insulating member, thereby reducing the probability of the lower insulating member 2 being melted by heat, thereby improving the safety performance of the secondary battery.

[0128] Among them, the implementation method of the second thermal insulation layer can be roughly the same as the implementation method of the first thermal insulation layer 8. Please refer to the above for details, and no further details will be given here.

[0129] In addition, the outer circumferential surface of the pole 3 located between the flange 33 and the pressure ring 5 has a first planar structure, the hole wall of the second through hole 23 has a second planar structure, and the hole wall of the third through hole 63 has a third planar structure, and the first planar structure is respectively abutted against the second planar structure and the third planar structure; the outer circumferential surface of the main body 61 has a fourth planar structure, and the groove side wall of the sink groove 26 has a fifth planar structure, and the fourth planar structure is abutted against the fifth planar structure.

[0130] Thus, the torque applied to the pole 3 can be transmitted to the top cover 1 and the lower insulating member 2, and to the lower insulating member 2 through the heat insulating member 6, thereby effectively improving the torsional resistance of the pole 3 and facilitating the improvement of the performance of the secondary battery.

[0131] Among them, the first planar structure can be a hexagonal structure, a pentagonal structure, a quadrilateral structure, an octagonal structure, etc., which is not limited here. The corresponding second planar structure and the third planar structure can be structures substantially the same as the first planar structure. The fourth planar structure can be a quadrilateral structure, a hexagonal structure, a pentagonal structure, an octagonal structure, etc., which is not limited here. The corresponding fifth planar structure can be a structure substantially the same as the fourth planar structure.

[0132] The above-mentioned sealing member 4 can be a sealing ring, which is sleeved on the outer peripheral surface of the pole 3. A second chamfer can be provided at the edge of the inner hole of the sealing ring, so that when the sealing ring is arranged on the pole 3, the second chamfer can play a certain guiding role, so that the installation of the sealing member 4 can be relatively quick and convenient.

[0133] In addition, the top cover assembly 10 also includes an upper insulating member 9, which has a mounting hole and is sleeved on the outer peripheral surface of the pole 3 through the mounting hole. Along the axial direction of the pole 3, the upper insulating member 9 is located between the flange 33 and the top cover 1, that is, one side of the upper insulating member 9 abuts against the flange 33, and the other side abuts against the top cover 1, so as to prevent contact short circuit between the pole 3 and the top cover 1, thereby improving the safety of the secondary battery.

[0134] Optionally, the seal 4 may be located between the outer circumferential surface of the pole 3 and the wall of the mounting hole, so that the upper insulating member 9 can provide a certain degree of protection for the seal 4, thereby improving the sealing stability of the seal 4 and improving the safety performance of the secondary battery.

[0135] The present application also provides an energy storage device, such as Fig.10 As shown, it includes a shell 30, a battery cell 20 and a top cover assembly 10 of any one of the above embodiments, wherein the shell 30 has a accommodating cavity and an opening connected to the accommodating cavity; the battery cell 20 is accommodated in the accommodating cavity; and the top cover assembly 10 is sealed at the opening, and the pressure ring 5 is electrically connected to the battery cell 20.

[0136] In this embodiment, the top cover assembly 10 of the energy storage device 100 is the top cover assembly 10 described in the above embodiment. Therefore, the top cover assembly 10 in this embodiment has the technical effect of the top cover assembly 10 in the above embodiment. Since the above embodiment has fully explained the technical effect of the top cover assembly 10, it will not be repeated here.

[0137] The present application also provides an electricity system, such as Fig.11 As shown, an energy storage device 100 including any one of the above embodiments.

[0138] In this embodiment, the energy storage device 100 of the power system 1000 is the energy storage device 100 described in the above embodiment. Therefore, the energy storage device 100 in this embodiment has the technical effect of the energy storage device 100 in the above embodiment. Since the above embodiment has fully described the technical effect of the energy storage device 100, it will not be repeated here.

[0139] In addition, the power system 1000 may also include an electric energy conversion device 200 and an electric load 300. The electric energy conversion device 200 is used to convert other forms of energy into electric energy. The energy storage device 100 can store at least part of the electric energy converted by the electric energy conversion device 200. The energy storage device 100 is also used to provide electric energy to the electric load 300. For example, the electric load 300 is household appliances and street lights. When the power grid is disconnected or there is a power outage, the energy storage device 100 can supply power to the household appliances and street lights.

[0140] In addition, the electric energy conversion device 200 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy and mechanical energy into electric energy. The electric energy conversion device 200 can be a solar panel, a windmill, a geothermal power generation device, etc.

[0141] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A top cover assembly, characterized in that: include: A top cover, wherein the top cover has a first through hole; A lower insulating member, the lower insulating member comprising a first surface and a second surface opposite to each other, and a second through hole penetrating the first surface and the second surface, the first surface abuts against the top cover, and the second through hole corresponds to the position of the first through hole; A pole, the pole having a first end and a second end, the second end sequentially passing through the first through hole and the second through hole, the first end extending along the radial direction of the pole to form a flange; A sealing member, the sealing member is sleeved on the outer peripheral surface of the pole and is located between a surface of the top cover away from the first surface and the flange along the axial direction of the pole; A pressure ring welded to the second end; as well as, A heat insulating member, comprising a main body, at least one first supporting portion and a third through hole, wherein the main body is sleeved on the outer circumferential surface of the pole through the third through hole, and is arranged between the second surface and the pressure ring along the axial direction of the pole, the first supporting portion is arranged on a side of the main body facing the second surface, and the first supporting portion abuts against the second surface, so that a gap is formed between the main body and the second surface along the axial direction of the pole.

2. The top cover assembly according to claim 1, characterized in that: The first supporting portion comprises a supporting ring, and the supporting ring is arranged on a surface of the main body facing the second surface along the circumference of the third through hole.

3. The top cover assembly according to claim 2, characterized in that: The support ring comprises a first sub-support ring and a second sub-support ring which are coaxially arranged. The first sub-support ring and the second sub-support ring are arranged on a surface of the body facing the second surface at intervals along the radial direction of the pole.

4. The top cover assembly according to claim 3, characterized in that: The first sub-support ring is disposed close to the third through hole, and the second sub-support ring is disposed close to the outer peripheral edge of the body.

5. The top cover assembly according to claim 1, characterized in that: The first supporting portion includes a plurality of first supporting protrusions, and the plurality of first supporting protrusions are arranged at intervals along the circumferential direction of the body on a surface of the body facing the second surface.

6. The top cover assembly according to any one of claims 1 to 5, characterized in that: A protrusion extends from the edge of the second through hole toward the top cover, and along the radial direction of the pole, the protrusion is located between the outer peripheral surface of the pole and the hole wall of the first through hole.

7. The top cover assembly according to claim 6, characterized in that: Along the axial direction of the pole, the sealing member is at least partially opposite to the protruding portion and has a first interval with the protruding portion.

8. The top cover assembly according to claim 7, characterized in that: Along the axial direction of the pole, the protrusion is lower than the surface where the top cover abuts against the sealing member, so that the first interval is formed between the protrusion and the sealing member, and / or, Along the axial direction of the pole, the sealing member is provided with a first groove at a position corresponding to the protruding portion, so that the first gap is formed between the protruding portion and a groove bottom wall of the first groove.

9. The top cover assembly according to any one of claims 1 to 5, characterized in that: A first heat insulation layer is coated on the surface of the flange that contacts the seal, and a projection of the seal on the flange along the axial direction of the pole is located on the first heat insulation layer.

10. The top cover assembly according to any one of claims 1 to 5, characterized in that: At least one avoidance hole is provided on the lower insulating member; At least one second supporting portion is further provided on a surface of the main body facing the lower insulating member. The second supporting portion is penetrated through the avoidance hole and abuts against the second surface of the top cover.

11. The top cover assembly according to any one of claims 1 to 5, characterized in that: A recessed groove is provided on the second surface, the pressure ring is at least partially accommodated in the recessed groove, the heat insulating member is located between the bottom wall of the recessed groove and the pressure ring, the outer peripheral surface of the pressure ring corresponds to the groove side wall of the recessed groove along the radial direction of the pole, the outer peripheral edge of the pressure ring is provided with a first chamfer, and the groove side wall of the recessed groove is provided with a second groove, so that a second gap is formed between at least a portion of the groove side wall and the outer peripheral surface of the pressure ring.

12. The top cover assembly according to claim 11, characterized in that: The outer peripheral surface of the pole located between the flange and the pressure ring has a first planar structure, the hole wall of the second through hole has a second planar structure, the hole wall of the third through hole has a third planar structure, and the first planar structure abuts against the second planar structure and the third planar structure respectively; The outer peripheral surface of the body has a fourth planar structure, the groove side wall of the sink groove has a fifth planar structure, and the fourth planar structure abuts against the fifth planar structure.

13. An energy storage device, characterized in that: include: A housing, wherein the housing has a receiving cavity and an opening communicating with the receiving cavity; A battery cell, the battery cell being accommodated in the accommodation cavity; as well as, The top cover assembly according to any one of claims 1 to 12, wherein the top cover assembly is sealed at the opening, and the pressure ring is electrically connected to the battery cell.

14. An electricity system, characterized in that: Includes the energy storage device as claimed in claim 13.

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