End cap assembly, battery cell, battery module, and device

Abstract

The embodiment of the present application provides a kind of end cap assembly, battery cell, battery module and device, end cap assembly is used for battery cell, end cap assembly includes: end cap;Electrode terminal is set to end cap;Insulating piece is used to insulate electrode terminal and end cap, is sleeved on electrode terminal;Wherein, insulating piece and electrode terminal abut, at least one of insulating piece and electrode terminal is provided with stress release slot, stress release slot is configured to absorb the stress generated when electrode terminal and insulating piece abut each other.The embodiment of the present application is provided with stress release slot on insulating piece and / or electrode terminal, the stress generated when electrode terminal and insulating piece abut each other can be absorbed by stress release slot, to reduce the stress received by insulating piece, to avoid that insulating piece therefore occurs crack, affect the safety performance of end cap assembly, therefore the embodiment of the present application can improve the safety performance of end cap assembly.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage devices, in particular to an end cover assembly, a battery monomer, a battery module and a device. BACKGROUND

[0002] With the development of science and technology, the application field of the battery monomer is more and more extensive, for example, the battery monomer can be used in automobiles, electric bicycles or wireless power tools, etc. At the same time, the safety performance requirement of the battery monomer is also higher and higher.

[0003] At present, the battery monomer of the prior art usually comprises a shell, an electrode assembly located in the shell and an end cover assembly arranged at the opening of the shell. The end cover assembly is provided with an insulating part and an electrode terminal and other components. The safety performance of the end cover assembly directly affects the safety performance of the whole battery monomer.

[0004] Therefore, there is an urgent need for a new end cover assembly, a battery monomer, a battery module and a device. SUMMARY

[0005] The present application provides an end cover assembly, a battery monomer, a battery module and a device, which aims to improve the safety performance of the end cover assembly.

[0006] In one aspect, the present application provides an end cover assembly for a battery monomer, comprising: an end cover; an electrode terminal arranged on the end cover; and an insulating part arranged on the electrode terminal and configured to insulate the electrode terminal and the end cover, wherein the insulating part and the electrode terminal are in abutment, at least one of the insulating part and the electrode terminal is provided with a stress release groove configured to absorb stress generated by the abutment of the electrode terminal and the insulating part.

[0007] According to one aspect of the present application, the insulating part is provided with a through hole, and the electrode terminal comprises a columnar portion arranged in the through hole and in abutment with the hole wall of at least part of the through hole.

[0008] The stress release groove is arranged circumferentially along the through hole to absorb radial stress generated by the abutment of the columnar portion and the hole wall.

[0009] According to one aspect of the present application, the stress release groove is arranged on the electrode terminal, and the stress release groove is formed by the concave of the outer wall of the columnar portion.

[0010] According to one aspect of the present application, the stress release groove is arranged on the insulating part.

[0011] The stress release groove is formed by the concave of the hole wall.

[0012] Alternatively, part of the hole wall is provided with two or more protrusions in the form of protrusions, the protrusions are in abutment with the columnar portion, and the two or more protrusions are distributed at intervals along the circumference of the columnar portion to form a stress release groove between adjacent two protrusions.

[0013] According to an aspect of the present application, the stress release groove is a plurality of stress release grooves, and the plurality of stress release grooves are symmetrically arranged along the circumference of the through hole.

[0014] According to an aspect of the present application, the cross section of the stress release groove in the axial direction is V-shaped, U-shaped or circular arc-shaped.

[0015] According to an aspect of the present application, the stress release groove is arranged on the insulating member;

[0016] The stress release groove is formed by recessing the surface of the insulating member away from the end cover;

[0017] And / or, the stress release groove is formed by recessing the surface of the insulating member towards the end cover.

[0018] According to an aspect of the present application, the stress release groove is annular and arranged around the electrode terminal;

[0019] Alternatively, the stress release groove is a plurality of stress release grooves, and the plurality of stress release grooves are spaced apart around the electrode terminal.

[0020] According to an aspect of the present application, the end cover comprises a connecting hole, and the electrode terminal is arranged in the connecting hole;

[0021] The insulating member comprises a main body portion and a positioning portion connected to the main body portion, and the positioning portion is arranged in the connecting hole.

[0022] On the other hand, the embodiments of the present application also provide a battery monomer, which comprises a shell, an electrode assembly arranged in the shell and an end cover assembly arranged at the opening of the shell, and the end cover assembly is the above-mentioned end cover assembly.

[0023] On the other hand, the embodiments of the present application also provide a battery monomer, which comprises a shell, an electrode assembly arranged in the shell and an end cover assembly arranged at the opening of the shell, and the end cover assembly is the above-mentioned end cover assembly.

[0024] On the other hand, the embodiments of the present application also provide a battery monomer, which comprises a shell, an electrode assembly arranged in the shell and an end cover assembly arranged at the opening of the shell, and the end cover assembly is the above-mentioned end cover assembly.

[0025] In the end cover assembly of the embodiments of the present application, the end cover assembly comprises an end cover, an electrode terminal and an insulating member, the insulating member is used for insulating the electrode terminal and the end cover, and the insulating member is sleeved on the electrode terminal. When the insulating member is sleeved on the electrode terminal, the insulating member and the electrode terminal abut against each other, and when the electrode terminal is deformed or shaken, the insulating member is prone to cracking. The embodiments of the present application are provided with a stress release groove on the insulating member and / or the electrode terminal, and the stress release groove can absorb the stress generated when the electrode terminal and the insulating member abut against each other, thereby reducing the stress suffered by the insulating member and avoiding the cracking of the insulating member, which affects the safety performance of the end cover assembly. Therefore, the embodiments of the present application can improve the safety performance of the end cover assembly. BRIEF DESCRIPTION OF DRAWINGS

[0026] Other features, objects, and advantages of the application will become more apparent from the following detailed description when read in conjunction with the accompanying drawings, in which like reference numerals indicate identical or similar components, wherein:

[0027] Figure 1 is a structural schematic diagram of a vehicle provided by an embodiment of the application;

[0028] Figure 2 is a structural schematic diagram of a battery pack provided by an embodiment of the application;

[0029] Figure 3 is a structural schematic diagram of a battery module provided by an embodiment of the application;

[0030] Figure 4 is a three-dimensional structural schematic diagram of a battery cell provided by an embodiment of the application;

[0031] Figure 5 is an exploded structural schematic diagram of Figure 4 ;

[0032] Figure 6 is an exploded structural schematic diagram of a top cover assembly in Figure 4 ;

[0033] Figure 7 is a three-dimensional structural schematic diagram of a battery cell provided by another embodiment of the application;

[0034] Figure 8 is an exploded structural schematic diagram of Figure 7 ;

[0035] Figure 9 is an exploded structural schematic diagram of a top cover assembly in Figure 7 ;

[0036] Figure 10 is a top view of a top cover assembly in Figure 7 ;

[0037] Figure 11 is a sectional view at A-A in Figure 10 ;

[0038] Figure 12 is a top view of an insulating piece of a top cover assembly provided by an embodiment of the application;

[0039] Figure 13 is a sectional view at B-B in Figure 12 ;

[0040] Figure 14 is a bottom view of an insulating piece of a top cover assembly provided by an embodiment of the application;

[0041] Figure 15is a perspective view of an insulating piece of a top cover assembly provided by an embodiment of the present application;

[0042] Figure 16 is a top view of an insulating piece of a top cover assembly provided by another embodiment of the present application;

[0043] Figure 17 is Figure 16 is a sectional view at C-C in FIG. 11;

[0044] Figure 18 is a bottom view of an insulating piece of a top cover assembly provided by another embodiment of the present application;

[0045] Figure 19 is a top view of an insulating piece of a top cover assembly provided by still another embodiment of the present application;

[0046] Figure 20 is a top view of an insulating piece of a top cover assembly provided by still another embodiment of the present application;

[0047] Figure 21 is a top view of an insulating piece of a top cover assembly provided by still another embodiment of the present application;

[0048] Figure 22 is Figure 21 is a sectional view at D-D in FIG. 13;

[0049] Figure 23 is a bottom view of an insulating piece of a top cover assembly provided by still another embodiment of the present application;

[0050] Figure 24 is Figure 22 is a partial enlarged structural schematic view at I in FIG. 15;

[0051] Figure 25 is a top view of an insulating piece of a top cover assembly provided by still another embodiment of the present application;

[0052] Figure 26 is Figure 25 is a sectional view at E-E in FIG. 17;

[0053] Figure 27 is a bottom view of an insulating piece of a top cover assembly provided by still another embodiment of the present application;

[0054] Figure 28 is a perspective view of an insulating piece of a top cover assembly provided by still another embodiment of the present application;

[0055] Figure 29 is a top view of an insulating piece of a top cover assembly provided by still another embodiment of the present application;

[0056] Figure 30Fig. 1 is a structure diagram of an electrode terminal of a top cover assembly according to an embodiment of the present application.

[0057] Reference numerals:

[0058] 1: battery pack; 10: battery cell; 11: battery module; 12: case; 2: vehicle body;

[0059] 100: end cover assembly;

[0060] 110: end cover; 111: connection hole;

[0061] 120: first insulating member; 120a: main body portion; 120b: positioning portion; 121: through hole; 121a: first through hole; 121b: second through hole; 122: hole wall; 123: protrusion;

[0062] 130: electrode terminal; 130a: first electrode terminal; 130b: second electrode terminal; 131: columnar portion;

[0063] 140: stress release groove;

[0064] 150: adapter piece;

[0065] 160: second insulating member;

[0066] 170: sealing ring;

[0067] 180: connection end plate;

[0068] 200: housing;

[0069] 300: electrode assembly; 310: first tab; 320: second tab;

[0070] X: thickness direction; Y: width direction; Z: height direction. DETAILED DESCRIPTION

[0071] Features and exemplary embodiments of various aspects of the present application will be described in detail below. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one of ordinary skill in the art that the present application can be practiced without some or all of these specific details. The description of the embodiments is merely illustrative of the present application and is not intended to limit the present application, as is apparent to one of ordinary skill in the art. In the following description, well-known structures and techniques have not been shown in order not to obscure the present application; and, for the sake of clarity, some structural and pictorial descriptions have been simplified in order not to obscure the present application. Furthermore, features, structures or characteristics described below can be combined in any suitable manner in one or more embodiments.

[0072] In the description of the present application, it should be noted that, unless otherwise specified, the meaning of "a plurality of" is more than two; the orientation or position relationship indicated by the terms "upper", "lower", "left", "right", "inner", "outer" and the like is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second" and the like are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0073] The orientation words appearing in the following description are the directions shown in the drawings, and do not limit the specific structure of the embodiments of the present application. In the description of the present application, it should be noted that, unless otherwise specified and limited, the terms "mounting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be directly connected, or indirectly connected. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0074] In order to better understand the present application, the following will be described in combination with Figures 1 to 30 The end cover assembly, the battery monomer, the battery module and the device of the embodiments of the present application are described in detail.

[0075] As Figure 1 shown, the embodiments of the present application first provide a vehicle, which comprises a battery pack 1 and a vehicle body 2, and the battery pack 1 is arranged on the vehicle body 2.

[0076] Among them, the vehicle is a new energy vehicle, which can be a pure electric vehicle, a hybrid vehicle or a range extender vehicle, or a two-wheeled or three-wheeled electric vehicle. The vehicle body 2 is provided with a driving motor, which is electrically connected with the battery pack 1 and is provided with electric energy by the battery pack 1. The driving motor is connected with the wheels on the vehicle body 2 through a transmission mechanism, so as to drive the vehicle to travel. For example, the battery pack 1 can be arranged horizontally at the bottom of the vehicle body 2.

[0077] Please refer to Figure 2 together, the arrangement mode of the battery pack 1 is various, and in some optional embodiments, the battery pack 1 comprises a box body 12 and a battery module 11 arranged in the box body 12.

[0078] The number of battery modules 11 is one or more, and a plurality of battery modules 11 are arranged in the box body 12. The type of the box body 12 is not limited, and the box body 12 can be a frame-shaped box body, a disc-shaped box body or a box-shaped box body, etc. Specifically, the box body 12 can comprise a lower box body for accommodating the battery module and an upper box body covering the lower box body.

[0079] Please refer to Figure 3The battery module 11 can be arranged in various ways. In some alternative embodiments, the battery module 11 comprises a receiving portion (not shown) and a plurality of battery cells 10 arranged in the receiving portion.

[0080] The receiving portion can be arranged in various ways. For example, the receiving portion comprises a housing and a cover plate arranged on the housing; or the receiving portion comprises side plates and end plates connected in sequence; or the receiving portion comprises end plates arranged oppositely and a hoop arranged around the end plates and the battery cells; or the receiving portion comprises side plates, end plates and a hoop.

[0081] It can be understood that the battery cell 10 can be applied to not only vehicles but also other devices. The embodiments of the present application further provide a device using the battery cell 10 as a power supply, which can be but is not limited to a vehicle, a ship or an aircraft.

[0082] The battery cell 10 can be arranged in various ways. In some alternative embodiments, please refer to Figures 4 to 5 , Figure 4 a perspective structural schematic view of a battery cell 10 provided by an embodiment of the present application; Figure 5 is Figure 4 an exploded structural schematic view of the battery cell 10. According to the battery cell 10 provided by the embodiment of the present application, the battery cell 10 is a prismatic battery cell 10.

[0083] In some alternative embodiments, please refer to Figure 7 and Figure 8 , Figure 7 a perspective structural schematic view of a battery cell 10 provided by another embodiment of the present application, Figure 8 is Figure 7 an exploded structural schematic view of the battery cell 10. According to the battery cell 10 provided by another embodiment of the present application, the battery cell 10 is a cylindrical battery cell 10.

[0084] Please refer to Figure 6 and Figure 9 , Figure 6 is an exploded structural schematic view of a top cover assembly of a prismatic battery cell 10 provided by an embodiment of the present application, Figure 9 is an exploded structural schematic view of a top cover assembly of a cylindrical battery cell 10 provided by another embodiment of the present application. According to the battery cell 10 provided by the embodiments of the present application, the prismatic battery cell 10 and the cylindrical battery cell 10 both comprise a housing 200, an electrode assembly 300 arranged in the housing 200 and an end cover assembly 100 arranged on an opening of the housing 200.

[0085] The electrode assembly 300 includes a tab, which is connected to the electrode terminal 130 on the end cap assembly 100 via an adapter piece 150, thereby outputting the electrical energy generated by the electrode assembly 300 to the outside.

[0086] For example, there are two electrodes, namely a first electrode 310 and a second electrode 320. For example, there are two electrode terminals 130, namely a first electrode terminal 130a and a second electrode terminal 130b. The first electrode terminal 130a and the second electrode terminal 130b are respectively connected to the first electrode 310 and the second electrode 320.

[0087] When the battery cell 10 is a prismatic battery cell 10, the electrode assembly 300 of the prismatic battery cell 10 includes, for example, a first electrode, a second electrode, and a separator (not shown in the figure), with the first electrode and the second electrode insulated from each other by the separator. The first electrode, the second electrode, and the separator can be formed into the electrode assembly 300 by winding or stacking, and the electrode assembly 300 generates electrical energy through a chemical reaction with the electrolyte. The first electrode is, for example, a positive electrode, and the second electrode is, for example, a negative electrode. Positive active material can be coated on the coated area of ​​the positive electrode, and negative active material can be coated on the coated area of ​​the negative electrode. The uncoated portion extending from the coated area of ​​the positive electrode serves as a positive electrode tab, for example, the first tab 310 can be a positive electrode tab; the uncoated portion extending from the coated area of ​​the negative electrode serves as a negative electrode tab, for example, the second tab 320 can be a negative electrode tab. The first electrode is electrically connected to the first electrode terminal 130a via the first electrode tab 310, and the second electrode is electrically connected to the second electrode terminal 130b via the second electrode tab 320, thereby outputting the generated electrical energy to the outside. The first electrode terminal 130a and the second electrode terminal 130b are both disposed on the end plate assembly 100.

[0088] The first tab 310 and the second tab 320 of the prismatic battery cell 10 are, for example, respectively disposed in the width direction of the battery cell 10. Figure 5 On both sides in the Y direction of the prismatic battery cell 10. It can be understood that the first tab 310 and the second tab 320 of the prismatic battery cell 10 may also be disposed, for example, in the height direction of the battery cell 10 (in the Y direction). Figure 5 On one side of the cylindrical battery cell 10 in the Z direction. The first tab 310 and the second tab 320 can, for example, be respectively disposed in the height direction of the battery cell 10 (in the Z direction). Figure 8 On both sides of the Z direction in the middle.

[0089] The cylindrical battery cell 10 may include, for example, two end cap assemblies 100, which are disposed on opposite sides of the cylindrical battery cell 10 in the height direction. It is understood that the cylindrical battery cell 10 may also include only one end cap assembly 100.

[0090] In some alternative embodiments, the end cover assembly 100 further comprises an end cover 110 and an insulating piece 1, the electrode terminal 130 is arranged on the end cover 110, the insulating piece is used to insulate the electrode terminal 130 and the end cover 110, and the insulating piece is sleeved on the electrode terminal 130.

[0091] The arrangement position of the insulating piece is not limited, for example, the insulating piece is a first insulating piece 120 arranged on the side of the end cover 110 away from the electrode assembly 300, or the insulating piece is a second insulating piece 160 arranged on the side of the end cover 110 facing the electrode assembly 300. Or the insulating piece comprises both the first insulating piece 120 and the second insulating piece 160. The embodiment of the present application takes the first insulating piece 120 as an example to illustrate the concept of the present application.

[0092] When the first insulating piece 120 is sleeved on the electrode terminal 130, the first insulating piece 120 and the electrode terminal 130 abut each other, and when the electrode terminal 130 deforms or shakes, the first insulating piece 120 is prone to cracking. For example, when the electrode terminal 130 is fixed to the end cover 110 by riveting, the electrode terminal 130 will expand during riveting, so that the electrode terminal 130 will press the first insulating piece 120, and the first insulating piece 120 may deform and crack under stress. When the first insulating piece 120 cracks to form a crack, metal particles may fall into the crack and thus reduce the creepage distance between the electrode terminal 130 and the end cover 110, causing short circuit of the end cover assembly 100 and affecting the safety performance of the end cover assembly 100.

[0093] The concept of the present application will be described below taking a cylindrical end cover assembly 100 as an example. Please refer to Figure 10 and Figure 11 , Figure 10 a top view of an end cover assembly 100 provided by an embodiment of the present application, Figure 11 a Figure 10 sectional view at A-A in FIG. 4.

[0094] According to the end cover assembly 100 provided by the embodiment of the present application, the end cover assembly 100 comprises: an end cover 110; an electrode terminal 130 arranged on the end cover 110; a first insulating piece 120 used to insulate the electrode terminal 130 and the end cover 110 and sleeved on the electrode terminal 130; wherein the first insulating piece 120 and the electrode terminal 130 abut each other, and at least one of the first insulating piece 120 and the electrode terminal 130 is provided with a stress release groove 140 configured to absorb stress generated by the abutment of the electrode terminal 130 and the insulating piece.

[0095] The stress release groove 140 can absorb the stress generated when the electrode terminal 130 abuts against the first insulating member 120, thereby reducing the stress received by the first insulating member 120, avoiding cracking of the first insulating member 120, and avoiding affecting the safety performance of the end cover 110. Therefore, the safety performance of the end cover assembly 100 can be improved.

[0096] It can be understood that the stress release groove 140 is arranged on at least one of the second insulating member 160 and the electrode terminal 130 when the second insulating member 160 is sleeved on the electrode terminal 130.

[0097] Please refer to Figures 12 to 15 , Figure 12 is a top view of the first insulating member 120 provided by an embodiment of the present application, Figure 13 is Figure 12 is a sectional view at B-B in FIG. 1, Figure 14 is a bottom view of the first insulating member 120 provided by an embodiment of the present application, Figure 15 is a perspective view of the first insulating member 120 provided by an embodiment of the present application.

[0098] According to some embodiments of the present application, when the electrode terminal 130 includes the first electrode terminal 130a and the second electrode terminal 130b, the first electrode terminal 130a and the second electrode terminal 130b can be sleeved by the same first insulating member 120.

[0099] It can be understood that in some other optional embodiments, the end cover assembly 100 can be sleeved on the first electrode terminal 130a and the second electrode terminal 130b by two first insulating members 120 respectively. The stress release groove 140 is arranged on at least one of the two first insulating members 120, the first electrode terminal 130a and the second electrode terminal 130b, to absorb the stress generated when the electrode terminal 130 abuts against the first insulating member 120. Optionally, the stress release groove 140 is arranged in each set of the first insulating member 120 and the electrode terminal 130 to absorb the stress applied by each electrode terminal 130 respectively.

[0100] In some optional embodiments, the end cover assembly 100 further includes a connecting end plate 180, the connecting end plate 180 is arranged on a side of the first insulating member 120 away from the end cover 110, and the electrode terminal 130 is connected to the connecting end plate 180. For example, the riveting hole is arranged on the connecting end plate 180, and one end of the electrode terminal 130 is located in the riveting hole.

[0101] For example, the electrode terminal 130 is inserted into the first insulating member 120 from the side of the first insulating member 120 facing the end cover 110, and then the electrode terminal 130 is further inserted into the riveting hole of the connecting end plate 180, and the electrode terminal 130 is riveted in the riveting hole. The first insulating member 120 is arranged between the connecting end plate 180 and the end cover 110 by extrusion, and when the first insulating member 120 is subjected to stress generated by abutting of the electrode terminal 130, the first insulating member 120 is prone to cracking, so that the creepage distance between the connecting end plate 180 and the end cover 110 is difficult to guarantee. The stress release groove 140 provided in the embodiment of the present application can avoid the cracking of the first insulating member 120, causing short circuit of the end cover assembly 100, and affecting the safety performance of the end cover 110.

[0102] In some optional embodiments, the first insulating member 120 is provided with a through hole 121, and the electrode terminal 130 includes a columnar portion 131, which is sleeved in the through hole 121 and abuts against at least part of the hole wall 122 of the through hole 121. The hole wall 122 of the through hole 121 refers to the wall surface of the first insulating member 120 facing the through hole 121.

[0103] The stress release groove 140 can be arranged in various positions. In some optional embodiments, the stress release groove 140 is arranged along the circumference of the through hole 121 to absorb the radial stress generated by the abutment of the columnar portion 131 and the hole wall 122. The radial direction is perpendicular to the axial direction of the through hole 121, that is, the height direction, and the radial direction is, for example, the width direction or the thickness direction.

[0104] In these optional embodiments, the columnar portion 131 abuts against the hole wall 122, and the columnar portion 131 provides the hole wall 122 with radial stress. The stress release groove 140 is arranged on the circumferential side of the through hole 121, so that the stress release groove 140 can absorb the radial stress, thereby avoiding cracking of the first insulating member 120.

[0105] The stress release groove 140 can be arranged on the first insulating member 120 and / or the columnar portion 131 to absorb the radial stress generated by the abutment of the columnar portion 131 and the first insulating member 120.

[0106] In some optional embodiments, the stress release groove 140 is arranged on the first insulating member 120. When the stress release groove 140 is arranged on the first insulating member 120, the stress release groove 140 can be arranged on the hole wall 122, or the stress release groove 140 can be arranged on the surface of the first insulating member 120 facing the end cover 110, or the stress release groove 140 can be arranged on the surface of the first insulating member 120 facing away from the end cover 110.

[0107] For example, a stress relief groove 140 is provided in the hole wall 122, and the stress relief groove 140 is formed by a recess in the hole wall 122. This can reduce the contact area between the hole wall 122 and the columnar portion 131, and the stress relief groove 140 can provide a certain deformation space to the first insulating member 120, thereby preventing the first insulating member 120 from cracking.

[0108] In other alternative embodiments, please refer to [the document / reference]. Figures 16 to 18 , Figure 16 This is a top view of a first insulating member 120 provided in another embodiment of the present invention. Figure 17 for Figure 16 Sectional view at CC, Figure 18 This is a bottom view of a first insulating member 120 provided in another embodiment of the present invention.

[0109] According to another embodiment of the present invention, a portion of the hole wall 122 has two or more protrusions 123 that abut against the columnar portion 131. The protrusions 123 are distributed circumferentially along the electrode terminal 130 to form a stress relief groove 140 between adjacent protrusions 123. The abutment between the columnar portion 131 and the protrusions 123 further reduces the contact area between the columnar portion 131 and the first insulating member 120. The stress relief groove 140 formed between adjacent protrusions 123 provides deformation space for deformation of the protrusions 123 and other parts of the first insulating member 120, thereby preventing the first insulating member 120 from cracking.

[0110] When the stress relief groove 140 is provided on the columnar portion 131 and / or the hole wall 122, there are various distribution patterns for the stress relief groove 140. Please refer to the following for details. Figure 19 and Figure 20 The number of stress relief grooves 140 can be one, and one stress relief groove 140 is located on the periphery of the through hole 121.

[0111] In some alternative embodiments, there are multiple stress relief grooves 140, which are symmetrically distributed circumferentially around the through hole 121. The multiple symmetrically distributed stress relief grooves 140 can ensure that the first insulating member 120 is subjected to more balanced stress, and prevent the first insulating member 120 from cracking due to excessive local stress.

[0112] The stress relief groove 140 can be configured in various shapes. When the stress relief groove 140 is disposed on the hole wall 122 or the columnar portion 131, the cross-section of the stress relief groove 140 in the axial direction is V-shaped, U-shaped, or arc-shaped. The cross-section of the stress relief groove 140 in the axial direction can also be other shapes, as long as the stress relief groove 140 can absorb the stress when the electrode terminal 130 and the first insulating member 120 come into contact.

[0113] In some optional embodiments, the end cap 110 is provided with a connection hole 111, and the electrode terminal 130 is disposed in the connection hole 111, for example, the columnar portion 131 is disposed through the connection hole 111. The first insulating member 120 includes a main body portion 120a and a positioning portion 120b connected to the main body portion 120a, the positioning portion 120b being disposed within the connection hole 111. This increases the creepage distance between the columnar portion 131 and the end cap 110, improving the safety performance of the end cap assembly 100.

[0114] In some optional embodiments, the end cap assembly 100 may further include a sealing ring 170, which is sleeved on the columnar portion 131 and located on the side of the positioning portion 120b away from the main body portion 120a, thereby further improving the safety performance of the end cap assembly 100.

[0115] The positioning part 120b is, for example, cylindrical, and the through hole 121 includes a first through hole 121a located in the main body part 120a and a second through hole 121b located in the positioning part 120b.

[0116] The dimensions of the first through hole 121a and the second through hole 121b are not limited. In some optional embodiments, such as... Figure 17 As shown, the second through hole 121b has the same radial dimension as the first through hole 121a.

[0117] Alternatively, in some other alternative embodiments, please refer to [the following text is also provided]. Figures 21 to 24 , Figure 21 This is a top view of a first insulating member 120 provided in another embodiment of the present invention. Figure 22 yes Figure 21 Sectional view at DD in the middle. Figure 23 This is a bottom view of a first insulating member 120 provided in another embodiment of the present invention. Figure 24 yes Figure 22 A magnified schematic diagram of the structure at point I in the middle.

[0118] According to another embodiment of the present invention, the radial dimension of the second through hole 121b is larger than the radial dimension of the first through hole 121a, such that the hole wall 122 of the second through hole 121b and the columnar portion 131 are spaced by a predetermined distance, which can prevent the columnar portion 131 from squeezing the positioning portion 120b when it expands, deforms or shakes, thus preventing the positioning portion 120b from cracking.

[0119] When the stress relief groove 140 is provided on the hole wall 122, the stress relief groove 140 can be correspondingly provided on the main body 120a, or the stress relief groove 140 can extend from the main body 120a to the positioning part 120b. The stress relief groove 140 provided on the positioning part 120b can prevent the positioning part 120b from cracking under stress.

[0120] In some alternative embodiments, please refer to Figures 25 to 28 , Figure 25 is a top view of the first insulating member 120 according to another embodiment of the present application, Figure 26 is Figure 25 is a sectional view taken along line E-E in Figure 27 is a bottom view of the first insulating member 120 according to another embodiment of the present application. Figure 28 is a perspective view of the first insulating member 120 according to another embodiment of the present application.

[0121] According to another embodiment of the present application, the stress release groove 140 is formed on the surface of the first insulating member 120 facing the end cover 110. It can be understood that the stress release groove 140 can also be formed on the surface of the first insulating member 120 facing away from the end cover 110. Alternatively, the surface of the first insulating member 120 facing the end cover 110 and the surface of the first insulating member 120 facing away from the end cover 110 are both provided with the stress release groove 140. In these alternative embodiments, the stress release groove 140 can provide deformation space for the first insulating member 120, thereby avoiding cracking of the first insulating member 120.

[0122] When the stress release groove 140 is formed on the surface of the first insulating member 120 facing the end cover 110 and the surface of the first insulating member 120 facing away from the end cover 110, the stress release groove 140 is, for example, annular, and the annular stress release groove 140 is arranged around the through hole 121. The stress release groove 140 can absorb stress at different positions in the circumferential direction of the through hole 121.

[0123] Alternatively, please refer to Figure 29 In yet other alternative embodiments, the stress release groove 140 is a plurality of stress release grooves 140, and the plurality of stress release grooves 140 are symmetrically distributed in the circumferential direction of the through hole 121, so that the stress on the first insulating member 120 is more uniform. Figure 29 In the embodiment shown in

[0124] Alternatively, please refer to Figure 30 In other alternative embodiments, the stress release groove 140 is formed on the electrode terminal 130. That is, the columnar portion 131 abuts against the hole wall 122 through at least part of the outer wall, and the stress release groove 140 is formed on the outer wall. The stress release groove 140 can reduce the contact area between the columnar portion 131 and the hole wall 122, and can reduce the deformation amount of the columnar portion 131, thereby reducing the radial force applied by the columnar portion 131 to the hole wall 122, and avoiding cracking of the first insulating member 120.

[0125] It should be noted that when stress relief grooves 140 are provided on the outer walls of both the hole wall 122 and the columnar portion 131, the stress relief grooves 140 on the outer walls of the hole wall 122 and the columnar portion 131 are arranged opposite to each other, so that the stress relief grooves 140 are hollow. For example, when a protrusion 123 is provided on the hole wall 122, the protrusion 123 on the hole wall 122 and the stress relief groove 140 on the outer wall of the columnar portion 131 are misaligned to avoid the protrusion 123 being located inside the stress relief groove 140 and affecting the function of the stress relief groove 140.

[0126] In some optional embodiments, stress relief grooves 140 are provided on both the first insulating member 120 and the electrode terminal 130. The stress relief grooves 140 on the first insulating member 120 are disposed on its surface facing and / or away from the end cap 110, and the stress relief grooves 140 on the electrode terminal 130 are disposed on its outer wall.

[0127] Alternatively, in some other optional embodiments, the first insulating member 120 is provided with a stress relief groove 140, the stress relief groove 140 including a first stress relief groove 140 disposed on the surface of the first insulating member 120 facing and / or away from the end cap 110, and a second stress relief groove 140 disposed on the hole wall 122.

[0128] This invention can be implemented in other specific forms without departing from its spirit and essential characteristics. For example, the algorithm described in a particular embodiment can be modified without departing from the basic spirit of the invention. Therefore, the present embodiments are to be regarded as exemplary rather than limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and all changes falling within the meaning and scope of the claims and their equivalents are thus included within the scope of the invention.

Claims

1. An end cap assembly for a battery cell, characterized in that, include: End cap, including connection hole; The electrode terminal is riveted to the end cap and is disposed in the connection hole; An insulating component is provided to insulate the electrode terminal and the end cap. The insulating component has a through hole. The electrode terminal includes a columnar portion, which is fitted into the through hole and abuts against at least a portion of the hole wall. The insulating component includes a main body and a positioning portion connected to the main body, and the positioning portion is disposed within the connecting hole. The insulating member and the electrode terminal abut against each other. At least one of the hole wall of the insulating member and the columnar portion of the electrode terminal is provided with a stress relief groove. The stress relief groove is arranged circumferentially along the through hole to absorb the radial stress generated by the abutment between the columnar portion and the hole wall.

2. The end cap assembly according to claim 1, characterized in that, The stress relief groove is disposed on the electrode terminal, and the stress relief groove is formed by the recess of the outer wall of the columnar portion.

3. The end cap assembly according to claim 1, characterized in that, The stress relief groove is disposed on the insulating component; The stress relief groove is formed by the recess in the hole wall; Alternatively, a portion of the hole wall may protrude to form two or more protrusions that abut against the columnar portion. The two or more protrusions are distributed circumferentially along the columnar portion to form the stress relief groove between two adjacent protrusions.

4. The end cap assembly according to claim 1, characterized in that, There are multiple stress relief grooves, which are symmetrically arranged circumferentially along the through hole.

5. The end cap assembly according to any one of claims 1-4, characterized in that, The stress relief groove has a V-shaped, U-shaped, or arc-shaped cross-section in the axial direction.

6. The end cap assembly according to claim 1, characterized in that, The stress relief groove is disposed on the insulating component; The stress relief groove is formed by a recess in the surface of the insulating element away from the end cap; And / or, the stress relief groove is formed by a recess in the surface of the insulating element toward the end cap.

7. The end cap assembly according to claim 6, characterized in that, The stress relief groove is annular and surrounds the electrode terminal; Alternatively, there may be multiple stress relief grooves, which are distributed at intervals around the electrode terminals.

8. A single battery cell, characterized in that, include: A housing, an electrode assembly located within the housing, and an end cap assembly covering the opening of the housing, wherein the end cap assembly is the end cap assembly as described in any one of claims 1-7.

9. A battery module, characterized in that, Includes the battery cell as described in claim 8.

10. An apparatus, characterized in that, It includes the battery cell of claim 8, the battery cell being used to provide electrical energy.

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