End cap assembly, energy storage device, electrical equipment and household energy storage system

Abstract

The present application discloses an end cover assembly, an energy storage device, an electrical equipment, and a household energy storage system. Among them, the end cover assembly is applied to the energy storage device, and the energy storage device includes a current collector plate and an electrode assembly. The current collector plate includes an extension portion and a plate body portion. The extension portion is connected to one side of the plate body portion and extends away from the plate body portion, and a positioning hole is provided on the extension portion. The end cover assembly includes an insulating component, and the insulating component includes a body portion. The body portion has a first surface and a second surface which are oppositely arranged. The insulating component further includes a receiving groove, and the receiving groove is recessed in the second surface. The insulating component further includes a positioning post, and the positioning post protrudes from the bottom wall of the receiving groove. The extension portion is received in the receiving groove, and each positioning post passes through the positioning hole; the plate body portion is bent relative to the extension portion, and the extension portion is located between the plate body portion and the body portion; the end cover assembly is connected to the electrode assembly, the current collector plate is located between the end cover assembly and the electrode assembly, and the plate body portion is connected to the electrode assembly. The present application can improve the energy density of the energy storage device.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage, and in particular, to an end cover assembly, an energy storage device, an electrical equipment, and a household energy storage system. Background Art

[0002] With the increasing demand for secondary energy storage devices, people have higher and higher requirements for their various performances. Especially for the cycling performance of energy storage devices, and the energy density of energy storage devices is an important parameter to ensure the cycling performance of energy storage devices. Too low energy density per unit volume will lead to low capacity and poor cycling performance of energy storage devices. The existing cylindrical lithium-ion energy storage device is also a secondary energy storage device, which is composed of an end cover assembly, a current collector plate, an electrode assembly, and a cylindrical housing. The current collector plate connects the pole column of the end cover assembly and the tab of the electrode assembly. Since most of the existing current collector plates are flat, the connection part with the pole column and the connection part with the tab are on the same plane, so the current collector plate occupies a large space inside the secondary energy storage device. In the same volume, the space that the electrode assembly can occupy is smaller, which restricts the energy density of the secondary energy storage device. Summary of the Invention

[0003] The present application provides an end cover assembly, which can solve the technical problem that the current collector plate occupies a large gap inside the secondary energy storage device, resulting in the restriction of the energy density of the secondary energy storage device.

[0004] An end cover assembly is applied to an energy storage device. The energy storage device includes a current collector plate and an electrode assembly. The current collector plate includes an extension part and a plate body part. The extension part is connected to the plate body part, and at least one positioning hole is provided on the extension part. In the thickness direction of the extension part, the positioning hole penetrates through the extension part;

[0005] The end cover assembly includes an insulating component. The insulating component includes a body part, and the body part has a first surface and a second surface, and the first surface and the second surface are arranged opposite to each other.

[0006] The insulating component further includes a receiving groove, and the receiving groove is recessed in the second surface of the body part.

[0007] The insulating component further includes at least one positioning post, and the at least one positioning post protrudes from the bottom wall of the receiving groove.

[0008] The extension part is received in the receiving groove, and each positioning post passes through one positioning hole; the plate body part is bent relative to the extension part, and in the thickness direction of the insulating component, the plate body part covers the second surface;

[0009] The end cap assembly is connected to the electrode assembly. The current collector plate is located between the end cap assembly and the electrode assembly, and the disk body portion is connected to the electrode assembly.

[0010] In a possible implementation, the number of the positioning posts is two. Along the length direction of the accommodation groove, the two positioning posts are arranged in a staggered manner.

[0011] In a possible implementation, the end faces of the two positioning posts facing away from the accommodation groove are flush with the second surface, and the second surface and the positioning posts support the disk body portion.

[0012] In a possible implementation, the positioning post is a cylinder with a diameter of 1.5 mm - 3.0 mm.

[0013] In a possible implementation, the positioning post includes an end face facing away from the accommodation groove and a peripheral side surface connected to the end face. A chamfer is formed at the connection between the end face of the positioning post and the peripheral side surface of the positioning post, and the chamfer is inclined from the end face of the positioning post towards the peripheral side surface of the positioning post.

[0014] In a possible implementation, from the bottom wall of the accommodation groove towards the second surface, the cross-sectional area of the positioning post gradually decreases.

[0015] In a possible implementation, the insulating component further includes a first clamping portion and a second clamping portion. The first clamping portion and the second clamping portion are respectively arranged on two opposite groove side walls of the accommodation groove. There is a gap between the first clamping portion and the second clamping portion and the bottom wall of the accommodation groove. Along the thickness direction of the end cap assembly, the extending portion is limited in the gap between the first clamping portion and the bottom wall of the accommodation groove, and the gap between the second clamping portion and the bottom wall of the accommodation groove.

[0016] In a possible implementation, the body portion includes a peripheral side surface connecting the first surface and the second surface. The peripheral side surface has a notch, and along the length direction of the accommodation groove, the notch communicates with the accommodation groove; the first clamping portion and the second clamping portion are located on opposite sides of the notch.

[0017] The present application provides an energy storage device, including a housing, an electrode assembly, a current collector plate, and the end cap assembly as described above. The housing has an opening, the housing is provided with an accommodation cavity, the electrode assembly is accommodated in the accommodation cavity, the end cap assembly covers the opening, and the disk body portion is connected to the electrode assembly through the opening.

[0018] In a possible implementation, the current collector plate further includes a connecting portion that connects the plate body portion and the extending portion. The connecting portion is made of a flexible material, and by bending the connecting portion, the plate body portion can be bent relative to the extending portion.

[0019] In a possible implementation, the number of the positioning holes is two, and along the length direction of the extending portion, the two positioning holes are arranged in a staggered manner.

[0020] In a possible implementation, the positioning hole is circular, the aperture of the positioning hole is larger than the diameter of the positioning post, and the difference between the aperture of the positioning hole and the diameter of the positioning post is 0.5 mm - 1.0 mm.

[0021] In a possible implementation, a plurality of limiting pieces are provided in the positioning hole. The plurality of limiting pieces extend from the hole wall of the positioning hole towards the axis direction of the positioning hole, and the plurality of limiting pieces are arranged at intervals around the axis of the positioning hole; the ends of the plurality of limiting pieces away from the hole wall of the positioning hole form a through hole, and the aperture of the through hole is smaller than the diameter of the positioning post.

[0022] In a possible implementation, a plurality of limiting pieces are provided in the positioning hole. The plurality of limiting pieces are formed by cutting slits along the radial direction of the positioning hole from the hole wall of the positioning hole, and there is a slit between every two limiting pieces. Along the thickness direction of the extending portion, the slit penetrates through the two opposite surfaces of the extending portion.

[0023] In a possible implementation, the extending portion includes a first surface and a second surface. Along the thickness direction of the extending portion, the first surface and the second surface are arranged opposite to each other. A plurality of limiting pieces protrude from the hole wall of the positioning hole and are arranged at intervals around the axis of the positioning hole; each limiting piece bends and extends from the first surface towards the second surface.

[0024] In a possible implementation, the positioning post is a plastic part, the limiting piece is a metal piece, the end of the limiting piece abuts against the circumferential surface of the positioning post, and the end of the limiting piece presses against the circumferential surface of the positioning post to form a notch.

[0025] In a possible implementation, along the width direction of the extending portion, the extending portion includes two opposite side edges. The number of the positioning holes is two, and along the width direction of the extending portion, the two positioning holes are arranged in a staggered manner. Among the plurality of limiting pieces in each positioning hole, the one with the shortest distance to the side edge of the extending portion extends in a direction perpendicular to the length direction of the extending portion.

[0026] In a possible implementation, a convex ring protrudes from the second surface of the extending portion, and the convex ring surrounds the edge of the positioning hole.

[0027] In a possible implementation manner, the disc body includes a main body and welding protrusions, the main body has a central axis, and the welding protrusions are protruded from a surface of the main body and are evenly distributed around the central axis.

[0028] The present application also provides an electrical device, comprising the energy storage device as described above, wherein the energy storage device is used to supply power to the electrical device.

[0029] The present application also provides a household energy storage system, comprising the energy storage device, the electric energy conversion device and the user load as described above, wherein the energy storage device stores the electric energy of the electric energy conversion device and transmits the electric energy to the user load.

[0030] The present application bends the current collecting disc so that the disc body of the current collecting disc is overlapped on the side of the extension part facing away from the insulating component. Compared with the extension part and the disc body being in the same plane, the space occupied by the current collecting disc inside the energy storage device can be reduced, the space utilization rate of the energy storage device can be improved, and the energy density of the energy storage device can be further improved. The extension part is accommodated in the receiving groove of the insulating component, and the positioning column in the receiving groove is penetrated through the positioning hole of the extension part. The positioning column can limit the extension part; at the same time, during the bending process of the current collecting disc, the positioning column can limit the extent to which the extension part is driven to tilt away from the receiving groove due to the bending operation, thereby avoiding the end of the extension part from breaking at the welding edge with the flange part of the pole, thereby ensuring the connection reliability between the end of the extension part of the current collecting disc and the flange part of the pole, making the bending process faster and more labor-saving, and further improving the yield rate and efficiency of mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the implementation manner will be briefly introduced below. Obviously, the drawings described below are only some implementation manners of the present application. For ordinary technicians in this field, other drawings can be obtained like these drawings without paying any creative work.

[0032] Figure 1 An application scenario diagram of the energy storage device provided in the embodiment of the present application;

[0033] Figure 2 A schematic diagram of partial structural decomposition of an energy storage device provided in an embodiment of the present application;

[0034] Figure 3 for Figure 2 A schematic diagram of a partial structural breakdown of an end cap assembly of the energy storage device shown;

[0035] Figure 4 for Figure 3 A schematic diagram of a partial structural breakdown of the end cap assembly from another angle;

[0036] Figure 5 is Figure 3 a schematic structural view of the top cover shown;

[0037] Figure 6 is Figure 5 a schematic structural view of the top cover shown from another angle;

[0038] Figure 7 is Figure 3 a schematic structural view of the insulating component shown;

[0039] Figure 8 is Figure 7 a schematic structural view of the insulating component shown from another angle;

[0040] Figure 9 is Figure 3 a schematic cross-sectional view of the end cap assembly shown;

[0041] Figure 10 is Figure 2 a schematic structural view of the current collector shown, which shows the first embodiment of the current collector;

[0042] Figure 11 is Figure 10 a schematic structural view of the current collector shown from another angle;

[0043] Figure 12 is Figure 2 a schematic view of the assembly process of the end cap assembly shown and Figure 10 the current collector of the first embodiment shown, where the current collector is in an unfolded state;

[0044] Figure 13 is Figure 12 a schematic view of the assembly of the end cap assembly of the energy storage device shown, where the current collector is in a folded state;

[0045] Figure 14 is Figure 2 a schematic structural view of the second embodiment of the current collector shown;

[0046] Figure 15 is Figure 2 a schematic view of the assembly process of the end cap assembly shown and Figure 14 the current collector of the second embodiment shown, where the current collector is in an unfolded state;

[0047] Figure 16 is Figure 2 a schematic structural view of the third embodiment of the current collector shown;

[0048] Figure 17 is Figure 2 a schematic structural view of the fourth embodiment of the current collector shown;

[0049] Figure 18 The Figure 2 schematic diagram of the assembly process of the end cover assembly shown and Figure 17 the current collector plate of the fourth embodiment shown, where the current collector plate is in an unfolded state;

[0050] Figure 19 The Figure 2 structural schematic diagram of the fifth embodiment of the current collector plate shown;

[0051] Figure 20 The Figure 2 schematic diagram of the assembly process of the end cover assembly shown and Figure 19 the current collector plate of the fifth embodiment shown, where the current collector plate is in an unfolded state;

[0052] Figure 21 The Figure 2 partial structural exploded view of the energy storage device shown.

[0053] The nouns corresponding to the reference numerals in the figure are: 5000 household energy storage system, 4000 power conversion device, 3000 user load 1, 2000 user load 2, 1000 energy storage device, 400 housing, 300 electrode assembly, 310 cell body, 320 tab, 100 end cover assembly, 200 current collector plate, 20 top cover, 21 top cover body, 211 pole hole, 212 liquid injection hole, 213 first mounting surface, 2131 mounting groove, 2132 liquid injection groove, 214 second mounting surface, 2141 protrusion, 215 through groove, 22 explosion-proof valve, 10 insulating member, 11 body portion, 111 first surface, 112 second surface, 113 circumferential side surface, 114 pole through hole, 115 ventilation groove, 1151 groove bottom wall, 1152 ventilation hole, 116 liquid injection through groove, 1161 groove bottom wall, 1162 liquid injection through hole, 13 accommodation groove, 131 first groove side wall, 132 second groove side wall, 133 third groove side wall, 134 groove bottom wall, 135 notch, 14 positioning post, 151 first clamping portion, 1511 first pressing body, 1512 first abutting body, 152 second clamping portion, 1521 second pressing body, 1522 second abutting body, 40 disk body portion, 41 body, 411 third surface, 412 fourth surface, 413 electrolyte hole, 414 groove, 42 welding protrusion, 50 connecting portion, 60 extending portion, 61 first surface, 62 second surface, 63 positioning hole, 631 limiting piece, 631a limiting piece, 632 through hole, 634 slit, 638 convex ring, 64 first notch, 65 second notch, 30 upper plastic, 31 through hole, 70 pressing block, 80 pole, 81 column body, 82 flange portion, 90 sealing ring. Detailed Description of the Invention

[0054] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts belong to the scope of protection of the present application.

[0055] Since the energy required by people has strong temporality and spatiality, in order to rationally utilize energy and improve the energy utilization rate, it is necessary to store one form of energy in the same or converted into another form of energy through a medium or device, and then release it in a specific energy form based on future application needs. As is well known, to achieve the major goal of carbon neutrality, the current main way to generate green electricity is to develop green energy such as photovoltaic and wind power to replace fossil energy. Currently, the generation of green electricity generally depends on photovoltaic, wind power, water potential, etc. However, wind energy and solar energy generally have problems such as strong intermittency and large volatility, which will cause grid instability, insufficient electricity during peak electricity consumption, too much electricity during low electricity consumption, and unstable voltage will also damage the power. Therefore, the problem of "abandoning wind and light" may be caused due to insufficient electricity demand or insufficient grid acceptance capacity. To solve these problems, energy storage is required. That is, electricity is converted into other forms of energy through physical or chemical means and stored, and the energy is converted into electricity and released when needed. Simply put, energy storage is similar to a large "portable charger". When photovoltaic and wind energy are sufficient, the electricity is stored, and the stored electricity is released when needed.

[0056] Taking electrochemical energy storage as an example, this solution provides an energy storage device. A group of chemical batteries are arranged in the energy storage device, mainly using the chemical elements in the chemical batteries as the energy storage medium. The charge and discharge process is accompanied by chemical reactions or changes of the energy storage medium. Simply put, the electricity generated by wind energy and solar energy is stored in the chemical batteries, and the stored electricity is released when the external electricity usage reaches the peak, or transferred to places with a shortage of electricity for further use.

[0057] Currently, the application scenarios of energy storage (i.e., energy storage) are relatively wide, including power generation side energy storage, grid side energy storage, renewable energy grid connection energy storage, and user side energy storage, etc. The types of corresponding energy storage devices include:

[0058] (1) A large energy storage container applied to the grid side energy storage scenario, which can be used as a high-quality active and reactive power regulation power source in the grid, realize the load matching of electric energy in time and space, enhance the consumption capacity of renewable energy, and is of great significance in grid system standby, relieving the power supply pressure during peak loads, and peak shaving and frequency modulation;

[0059] (2) Small and medium-sized energy storage cabinets applied to industrial and commercial energy storage scenarios (such as banks, shopping malls, etc.) on the user side and household small energy storage boxes applied to household energy storage scenarios on the user side mainly operate in the mode of "peak shaving and valley filling". Due to the large price difference in electricity charges at peak and valley positions according to electricity consumption demands, after users have energy storage devices, in order to reduce costs, they usually charge the energy storage cabinet / box during the low electricity price period; during the peak electricity price period, they then discharge the electricity in the energy storage device for use to achieve the purpose of saving electricity charges. In addition, in remote areas and areas with high incidences of natural disasters such as earthquakes and hurricanes, the existence of household energy storage devices is equivalent to users providing backup power for themselves and the power grid, eliminating the inconvenience caused by frequent power outages due to disasters or other reasons.

[0060] Figure 1 This is the application scenario diagram of the energy storage device provided by the embodiment of the present application. The embodiment of the present application takes the household energy storage scenario in user-side energy storage as an example for illustration, and the energy storage device of the present application is not limited to the household energy storage scenario.

[0061] The present application provides a household energy storage system 5000, which includes an electric energy conversion device (photovoltaic panel) 4000, user loads 1 (street lights) 3000, user loads 2 (household appliances) 2000, etc., and an energy storage device 1000. The energy storage device 1000, as a small energy storage box, can be installed on an outdoor wall in a wall-mounted manner. Specifically, the photovoltaic panel can convert solar energy into electric energy during the low electricity price period, and the energy storage device 1000 is used to store the electric energy and supply it to street lights and household appliances for use during the peak electricity price period, or supply power when the power grid is powered off / out of power.

[0062] It can be understood that the energy storage device 1000 may include but is not limited to single cells, battery modules, battery packs, battery systems, etc. When the energy storage device 1000 is a single cell, it can be a cylindrical battery. The embodiment of the present application only takes the energy storage device 1000 as a cylindrical battery as an example for illustration.

[0063] Please refer to Figure 2 , Figure 2 shows a partial structural decomposition schematic diagram of the energy storage device provided by the embodiment of the present application. In this embodiment, the energy storage device 1000 includes a housing 400, an electrode assembly 300, an end cover assembly 100, and a current collector plate 200 connecting the electrode assembly 300 and the end cover assembly 100. The housing 400 includes an opening and a receiving cavity. The electrode assembly 300 is received in the receiving cavity, and the end cover assembly 100 is sealed to the opening. The current collector plate 200 is disposed on the side of the end cover assembly 100 close to the electrode assembly 300, and the current collector plate 200 is used to connect the tab of the electrode assembly 300 and the pole column of the end cover assembly 100.

[0064] The electrode assembly 300 includes a battery cell body 310 and electrode tabs 320. The battery cell body 310 is formed by stacking or winding a positive electrode sheet, a negative electrode sheet, and an insulating film located between the positive electrode sheet and the negative electrode sheet. Both the positive electrode sheet and the negative electrode sheet include a first portion coated with an active material and a second portion extending outward from the first portion and not coated with the active material. The electrode tabs 320 include a negative electrode tab and a positive electrode tab. The negative electrode tab corresponds to the second portion of the negative electrode sheet that is not coated with the active material, and the positive electrode tab corresponds to the second portion of the positive electrode sheet that is not coated with the active material. Along the height direction of the battery cell body 310, the negative electrode tab and the positive electrode tab are respectively located at opposite ends of the battery cell body 310.

[0065] It should be noted that the end cap assembly 100 provided in this application can be used to connect to the negative electrode tab of the electrode assembly 300 through the current collector plate 200, or can also be used to connect to the positive electrode tab of the electrode assembly 300 through the current collector plate 200. The embodiments of this application do not strictly limit this.

[0066] Please refer to Figure 2 、 Figure 3 and Figure 4 , Figure 3 For Figure 2 a partial structural exploded view of the end cap assembly of the energy storage device shown, Figure 4 For Figure 3 a partial structural exploded view of the end cap assembly from another angle shown. The end cap assembly 100 includes an insulating member 10 and a top cover 20. The top cover 20 and the insulating member 10 are stacked and can be fixedly connected, and the insulating member 10 is used to insulate the top cover 20 from the electrode assembly 300. In this embodiment, the top cover 20 is a light aluminum part, and the insulating member 10 is made of plastic material and is insulating.

[0067] Please refer to Figure 5 and Figure 6 , Figure 5 For Figure 3 the structural schematic diagram of the top cover shown; Figure 6 For Figure 5 the structural schematic diagram of the top cover from another angle shown. In this embodiment, the top cover 20 includes a top cover body 21 and an explosion-proof valve 22. The top cover body 21 also includes a pole hole 211 and a liquid injection hole 212. The pole hole 211 is located at the middle position of the top cover body 21, and the explosion-proof valve 22 and the liquid injection hole 212 are respectively located on opposite sides of the pole hole 211.

[0068] Specifically, the top cover body 21 is in the shape of a circular plate. Along the thickness direction of the top cover body 21, the top cover body 21 includes a first mounting surface 213 and a second mounting surface 214 which are arranged back to back. In this embodiment, the first mounting surface 213 is provided with a mounting groove 2131. The mounting groove 2131 is recessed in the middle position of the first mounting surface 213; along the thickness direction of the top cover body 21, the pole hole 211 penetrates through the bottom wall of the mounting groove 2131 and the second mounting surface 214 of the top cover body 21. The pole hole 211 is used for the pole of the energy storage device 1000 to pass through. In this embodiment, the mounting groove 2131 is a cross-shaped groove.

[0069] The first mounting surface 213 is further provided with a liquid injection groove 2132, and the liquid injection groove 2132 is recessed in the first mounting surface 213 and is located on the side of the mounting groove 2131. The second mounting surface 214 is convexly provided with a protruding portion 2141. The protruding portion 2141 is formed by the liquid injection groove 2132 being recessed into the first mounting surface 213 and protrudes from the second mounting surface 214. Along the thickness direction of the top cover body 21, the liquid injection hole 212 penetrates through the bottom wall of the liquid injection groove 2132 and the protruding portion 2141. In this embodiment, the liquid injection groove 2132 is a circular groove. In the liquid injection process of the energy storage device 1000, electrolyte is injected into the energy storage device 1000 through the liquid injection hole 212 on the top cover 20.

[0070] At the side position of the top cover body 21, there is also a through groove 215 that penetrates through the first mounting surface 213 and the second mounting surface 214, and the through groove 215 is located on the side of the mounting groove 2131 away from the liquid injection groove 2132. The explosion-proof valve 22 is accommodated in the through groove 215 and is welded to the groove wall of the through groove 215. When the internal pressure of the energy storage device 1000 is too high, the explosion-proof valve 22 will automatically open to release pressure to prevent explosion. In this embodiment, the top cover 20 may further include a protective film (not shown in the figure). The protective film is arranged at one end of the through groove 215 close to the first mounting surface 213, and the protective film can prevent foreign objects from entering the explosion-proof valve 22 or damaging the explosion-proof valve 22.

[0071] Please refer to Figure 7 、 Figure 8 , Figure 7 is Figure 3 the structural schematic diagram of the insulating component shown, Figure 8 and Figure 7 is

[0072] A pole post through-hole 114 is provided on the body portion 11. The pole post through-hole 114 is located at the middle position of the body portion 11. Along the thickness direction of the body portion 11, the pole post through-hole 114 penetrates through the first surface 111 and the second surface 112 of the body portion 11.

[0073] In this embodiment, the body portion 11 is a circular plate. On the first surface 111, air vent grooves 115 and liquid injection through-grooves 116 are respectively recessed in the direction of the second surface 112 on the opposite sides of the pole post through-hole 114. The bottom wall 1151 of the air vent groove 115 is provided with air vent holes 1152, and the air vent holes 1152 penetrate through the bottom wall 1151 of the air vent groove 115 and the second surface 112 of the body portion 11. The bottom wall 1161 of the liquid injection through-groove 116 is provided with liquid injection through-holes 1162, and the liquid injection through-holes 1162 penetrate through the bottom wall 1161 of the liquid injection through-groove 116 and the second surface 112 of the body portion 11.

[0074] As Figure 7 shown, a receiving groove 13 is further provided on the insulating component 10. The receiving groove 13 is recessed in the second surface 112 and has a notch 135. Specifically, the notch 135 penetrates through the circumferential side surface 113 of the body portion 11. It can also be understood that a notch 135 is provided on the circumferential side surface 113 of the body portion 11, and the notch 135 communicates with the receiving groove 13. The receiving groove 13 includes a first groove side wall 131, a second groove side wall 132, a third groove side wall 133 and a groove bottom wall 134. The first groove side wall 131, the second groove side wall 132 and the third groove side wall 133 are all convexly provided on the groove bottom wall 134 and extend in a direction away from the groove bottom wall 134; the first groove side wall 131, the second groove side wall 132 and the third groove side wall 133 are all arranged at an angle with the groove bottom wall 134. The second groove side wall 132 is connected between the first groove side wall 131 and the third groove side wall 133 to form a U-shaped structure. The pole post through-hole 114 penetrates through the first surface 111 of the body portion 11 and the groove bottom wall 134 of the receiving groove 13.

[0075] Specifically, the first groove side wall 131 and the third groove side wall 133 are respectively located on the opposite sides of the notch 135. The second groove side wall 132 is located on the side of the pole post through-hole 114 away from the notch 135 and is spaced opposite to the notch 135, and the pole post through-hole 114 is located between the notch 135 and the second groove side wall 132. It can be understood that the notch 135 is the opening of the receiving groove 13.

[0076] As Figure 8, the insulating member 10 further includes a positioning post 14. The positioning post 14 is cylindrical and protrudes from the bottom wall 134 of the accommodating groove 13. The diameter of the positioning post 14 is 1.5 mm - 3.0 mm. Specifically, it can be 1.5 mm, or 3.0 mm, or any value between 1.5 - 3.0 mm. By limiting the minimum diameter of the positioning post 14 to 1.5 mm, it can be avoided that the diameter of the positioning post 14 is too small, resulting in low strength of the positioning post 14 and preventing the positioning post 14 from being easily broken. By limiting the maximum diameter of the positioning post 14 to 3.0 mm, it can be avoided that the positioning hole 63 corresponding to the positioning post 14 on the extension part 60 is too large, thereby avoiding the narrow spacing between adjacent positioning holes 63 on the extension part 60 and reducing the strength of the extension part 60.

[0077] The end surface of the positioning post 14 facing away from the accommodating groove 13 is flush with the second surface 112 of the body part 11. The positioning post 14 is also provided with a chamfer. The positioning post 14 includes an end face away from the accommodating groove 13 and a circumferential side face connected to the end face. A chamfer is formed at the connection between the end face of the positioning post 14 and the circumferential side face of the positioning post 14, and the chamfer is inclined from the end face of the positioning post 14 towards the circumferential side face of the positioning post 14. It can be understood that along the thickness direction of the insulating member 10, the positioning post 14 is a frustum cone column. In other embodiments, the positioning post 14 can also be other shapes such as a conical column, etc., and the cross-section of the positioning post 14 gradually decreases from the bottom wall 134 of the accommodating groove 13 towards the second surface 112. The positioning post 14 can also protrude from the second surface 112 of the body part 11, or the positioning post 14 can also not protrude from the second surface 112 of the body part 11.

[0078] The number of the positioning posts 14 is at least one. In this embodiment, the number of the positioning posts 14 is two. Along the length direction of the accommodating groove 13, the two positioning posts 14 are arranged in a staggered manner; along the width direction of the accommodating groove 13, the two positioning posts 14 are also arranged in a staggered manner. Along the length direction or the width direction of the accommodating groove 13, the positioning posts 14 can also be arranged in alignment. In this embodiment, the positioning post 14 is made of plastic.

[0079] Please continue to refer to Figure 8, the insulating member 10 further includes a first clamping portion 151 and a second clamping portion 152. The first clamping portion 151 and the second clamping portion 152 are respectively provided on two opposite sides of the first groove side wall 131 and the third groove side wall 133, and the first clamping portion 151 and the second clamping portion 152 are close to the notch 135; it can be understood that the first clamping portion 151 and the second clamping portion 152 are located on opposite sides of the notch 135 of the receiving groove 13, and the first clamping portion 151 and the second clamping portion 152 are opposite in the direction where the first groove side wall 131 and the third groove side wall 133 are opposite. Along the thickness direction of the insulating member 10, there is a gap between the first clamping portion 151 and the second clamping portion 152 and the bottom wall 134 of the receiving groove 13. In other embodiments, the first clamping portion 151 and the second clamping portion 152 may also be arranged in a staggered manner in the direction where the first groove side wall 131 and the third groove side wall 133 are opposite.

[0080] The first clamping portion 151 includes a first pressing body 1511 and a first abutting body 1512. The first pressing body 1511 protrudes from the side of the first groove side wall 131 facing the third groove side wall 133, and the first pressing body 1511 is inclined towards the bottom wall 134 of the receiving groove 13. The first pressing body 1511 includes a first inclined surface, the first inclined surface faces away from the bottom wall 134 of the receiving groove 13, and the first inclined surface is connected to the wall surface of the first groove side wall 131 of the receiving groove 13 and is inclined towards the bottom wall 134 of the receiving groove 13. Along the thickness direction of the insulating member 10, the first abutting body 1512 is spaced from the first pressing body 1511. One end of the first abutting body 1512 is fixed to the side of the first groove side wall 131, and the other end is connected to the free end of the first pressing body 1511. Both the first pressing body 1511 and the first abutting body 1512 are elastic members. There is a gap between the first pressing body 1511 and the first abutting body 1512, that is, the first clamping portion 151 is a hollow structure as a whole, which can improve the elastic force of the first clamping portion 151. It can be understood that the first clamping portion 151 has a cavity, and the first clamping portion 151 is a hollow structure. The oblique design and the hollow design of the first clamping portion 151 can make it more labor-saving to squeeze the first clamping portion 151 downward. The first abutting body 1512 can support the first pressing body 1511 to prevent the first pressing body 1511 from deforming after multiple uses and affecting the repeated use of the first clamping portion 151. In this embodiment, the first pressing body 1511 and the first abutting body 1512 are integrally formed. In other embodiments, the first clamping portion 151 may also be a separate structural member, that is, the first clamping portion 151 may be a triangular block.

[0081] The second clamping portion 152 includes a second pressing body 1521 and a second abutting body 1522. The second pressing body 1521 protrudes from the side surface of the third groove side wall 133 facing the first groove side wall 131, and the second pressing body 1521 is inclined towards the bottom wall 134 of the accommodating groove 13. The second pressing body 1521 includes a second inclined surface, the second inclined surface faces away from the bottom wall 134 of the accommodating groove 13, and the second inclined surface is connected to the wall surface of the third groove side wall 133 of the accommodating groove 13 and is inclined towards the bottom wall 134 of the accommodating groove 13. Along the thickness direction of the insulating member 10, the second abutting body 1522 and the second pressing body 1521 are arranged at intervals. One end of the second abutting body 1522 is fixed to the side surface of the third groove side wall 133, and the other end is connected to the free end of the second pressing body 1521. Both the second pressing body 1521 and the second abutting body 1522 are elastic members; there is a gap between the second pressing body 1521 and the second abutting body 1522, which can enhance the elastic force of the second clamping portion 152. It can be understood that the second clamping portion 152 has a cavity, and the second clamping portion 152 is a hollow structure. The oblique design and hollow design of the second clamping portion 152 can make it more labor-saving to squeeze the second clamping portion 152 downward. The second abutting body 1522 can support the second pressing body 1521 to prevent the second pressing body 1521 from deforming after repeated use and affecting the repeated use of the second clamping portion 152. In this embodiment, the second pressing body 1521 and the second abutting body 1522 are integrally formed. In other embodiments, the second clamping portion 152 can also be a separate structural member, that is, the second clamping portion 152 can be a triangular block.

[0082] Please refer to Figure 9 , Figure 9 is Figure 3 a schematic cross-sectional view of the end cover assembly shown. The insulating member 10 is stacked on the second mounting surface 214 of the top cover 20. The first surface 111 of the insulating member 10 and the second mounting surface 214 of the top cover 20 are opposite and fit together. Along the thickness direction of the end cover assembly 100, the pole through hole 114 of the insulating member 10 and the pole hole 211 of the top cover 20 are coaxially arranged and communicate with each other through the pole through hole 114. Along the thickness direction of the end cover assembly 100, the ventilation groove 115 of the insulating member 10 and the through groove 215 of the top cover 20 are oppositely arranged and communicate with each other; the orthographic projection of the through groove 215 of the top cover 20 on the main body portion 11 falls within the orthographic projection of the ventilation groove 115 on the main body portion 11. Along the thickness direction of the end cover assembly 100, the liquid injection through groove 116 of the insulating member 10 and the liquid injection hole 212 of the top cover 20 are oppositely arranged and communicate with each other; the orthographic projection of the liquid injection hole 212 of the top cover 20 on the main body portion 11 falls within the orthographic projection of the liquid injection through groove 116 on the main body portion 11.

[0083] It can be understood that during the transportation of the energy storage device 1000, the tab or the separator membrane is prone to breakage and generate debris. The bottom wall 1151 of the ventilation groove 115 can prevent the debris of the tab or the separator membrane from floating below the explosion-proof valve 22, avoiding blocking the gas passage and thus causing explosion-proof failure. The bottom wall 1161 of the liquid injection through groove 116 can prevent the debris of the tab or the separator membrane from floating below the liquid injection hole 212, avoiding blocking the liquid injection hole 212 and thus affecting the liquid injection process.

[0084] Please refer to Figure 10 and Figure 11 , Figure 10 which is Figure 2 a schematic structural diagram of the current collector plate shown, Figure 11 and Figure 10 is another perspective structural diagram of the current collector plate shown. The current collector plate 200 includes a plate body portion 40, a connecting portion 50, and an extending portion 60. The plate body portion 40 is used for fixedly connecting with the tab 320 of the electrode assembly 300, and the extending portion 60 is used for fixedly connecting with the pole column of the end cap assembly 100. The connecting portion 50 is connected between the plate body portion 40 and the extending portion 60. By bending the connecting portion 50, the plate body portion 40 can be bent relative to the extending portion 60. In this embodiment, the current collector plate 200 is an overall sheet-like structure.

[0085] The plate body portion 40 includes a body 41 and welding protrusions 42. The body 41 has a central axis, and the welding protrusions 42 are provided on the body 41. The welding protrusions 42 are evenly distributed around the central axis of the body 41.

[0086] In this embodiment, the body 41 is disc-shaped. Along the thickness direction of the body 41, the body 41 includes a third surface 411 and a fourth surface 412 which are arranged opposite to each other.

[0087] The welding protrusions 42 protrude from the third surface 411 of the body 41. The welding protrusions 42 are generally strip-shaped plates and extend along the radial direction of the body 41. In this embodiment, the number of the welding protrusions 42 is 4. The welding protrusions 42 are evenly distributed around the central axis of the body 41, which is equivalent to being circumferentially distributed around the center of the body 41, and the adjacent two welding protrusions 42 are spaced at an angular interval of 90° on the body 41. The welding protrusions 42 are used for welding with the tab 320 of the electrode assembly 300, that is, the tab 320 of the electrode assembly 300 is connected to the current collector plate 200 through the welding protrusions 42.

[0088] The body 41 is provided with an electrolyte hole 413 and a groove 414. The electrolyte hole 413 is located at the middle position of the body 41. Along the thickness direction of the body 41, the electrolyte hole 413 penetrates through the third surface 411 and the fourth surface 412 of the body 41. The electrolyte hole 413 is used for allowing the electrolyte to flow into the electrode assembly 300 during the liquid injection process.

[0089] The groove 414 is recessed in the fourth surface 412 of the body 41. In this embodiment, the groove 414 is generally strip-shaped and extends along the radial direction of the body 41; the number of grooves 414 is 4 and they are circumferentially distributed around the center of the body 41; the adjacent two grooves 414 are spaced at an angular interval of 90° on the body 41. Along the thickness direction of the body 41, the 4 welding protrusions 42 are respectively opposite to the positions where the 4 grooves 414 are located, that is, along the thickness direction of the disc portion 40, the orthographic projection of the welding protrusion 42 on the body 41 at least partially coincides with the orthographic projection of the groove 414 on the body 41.

[0090] It can be understood that by providing the groove 414 on the body 41 and making the groove 414 and the welding protrusion 42 opposite to each other along the thickness direction of the body 41, on the one hand, the combination of the groove 414 and the welding protrusion 42 has little impact on the overall strength of the disc portion 40, and on the other hand, providing the groove 414 can reduce the production materials for producing the disc portion 40, which is beneficial to reducing the production cost and weight of the current collector disc 200.

[0091] The connecting portion 50 is generally a rectangular thin plate. One end of the connecting portion 50 is connected to the circumferential surface of the body 41, and the other end is connected to the end of the extending portion 60. In this embodiment, the connecting portion 50 is made of a flexible material. It can be understood that the connecting portion 50 is connected between the body 41 and the extending portion 60 of the disc portion 40, and the extending portion 60 extends in the same direction as the connecting portion 50.

[0092] The extending portion 60 is generally a rectangular thin plate. The extending portion 60 is formed by extending from the side of the connecting portion 50 away from the body 41. In this embodiment, the extending direction of the extending portion 60 is the same as the extending direction of one welding protrusion 42.

[0093] Along the thickness direction of the extending portion 60, the extending portion 60 includes a first surface 61 and a second surface 62 arranged opposite to each other. The extending portion 60 is provided with positioning holes 63. Along the thickness direction of the extending portion 60, the positioning holes 63 penetrate through the first surface 61 and the second surface 62 of the extending portion 60. The number of positioning holes 63 is at least one. In this embodiment, the number of positioning holes 63 is 2. Along the length direction of the extending portion 60, the two positioning holes 63 are arranged in a staggered manner; along the width direction of the extending portion 60, the two positioning holes 63 are also arranged in a staggered manner. The shape of the positioning holes 63 is circular, the diameter of the positioning holes 63 is larger than the diameter of the positioning posts 14 of the insulating member 10, and the difference between the diameter of the positioning holes 63 and the diameter of the positioning posts 14 is 0.5 mm - 1.0 mm. Specifically, it can be 0.5 mm, or 1.0 mm, or any value between 0.5 - 1.0. In other embodiments, the positioning holes 63 can also be other shapes, such as rectangular, triangular, diamond-shaped, etc. Along the length direction or the width direction of the extending portion 60, the two positioning holes 63 can also be arranged in alignment.

[0094] The extension portion 60 is further provided with a first notch 64 and a second notch 65. Along the width direction of the extension portion 60, the first notch 64 and the second notch 65 are located on opposite sides of the end portion of the extension portion 60 connected to the connecting portion 50. Along the thickness direction of the extension portion 60, the first notch 64 and the second notch 65 penetrate through the first surface 61 and the second surface 62 of the extension portion 60.

[0095] Please refer to Figure 12 and Figure 13 , Figure 12 is Figure 2 a schematic diagram of the assembly process of the end cap assembly shown in Figure 10 and the current collector plate of the first embodiment shown, where the current collector plate is in an unfolded state; Figure 13 is Figure 12 a schematic diagram of the assembly of the end cap assembly of the energy storage device shown, where the current collector plate is in a folded state.

[0096] The extension portion 60 of the current collecting plate 200 is accommodated in the receiving groove 13 of the insulating component 10. Along the thickness direction of the insulating component 10, the positioning column 14 in the receiving groove 13 of the insulating component 10 is penetrated by the positioning hole 63 of the extension portion 60 of the current collecting plate 200, and the first notch 64 and the second notch 65 of the extension portion 60 of the current collecting plate 200 are respectively opposite to the first clamping portion 151 and the second clamping portion 152 of the insulating component 10. Specifically, along the thickness direction of the insulating component 10, the first clamping portion 151 is opposite to the first notch 64, and the second clamping portion 152 is opposite to the second notch 65. In the thickness direction of the insulating component 10 and toward the second surface 112, the first clamping portion 151 partially passes through the first notch 64, and the second clamping portion 152 partially passes through the second notch 65, until the first clamping portion 151 and the second clamping portion 152 press against the extension portion 60 for clamping, specifically, against the edge of the first notch 64 and the second notch 65; in this process, the extension portion 60 pushes against the first inclined surface of the first clamping portion 151 and the second inclined surface of the second clamping portion 152. The first clamping portion 151 and the second clamping portion 152 are deformed to facilitate the passage of the extension portion 60. It can be understood that, along the thickness direction of the insulating component 10, the first clamping portion 151 and the bottom wall 134 of the accommodating groove 13 limit (clamp) the extension portion 60 of the collecting plate 200, and the extension portion 60 is limited to the gap between the first clamping portion 151 and the bottom wall 134 of the accommodating groove 13; the second clamping portion 152 and the bottom wall 134 of the accommodating groove 13 limit (clamp) the extension portion 60 of the collecting plate 200, and the extension portion 60 is limited to the gap between the second clamping portion 152 and the bottom wall 134 of the accommodating groove 13. After the extension portion 60 of the collecting plate 200 is installed in the receiving groove 13, the first clamping portion 151 and the second clamping portion 152 can prevent the extension portion 60 of the collecting plate 200 from escaping from the receiving groove 13; at the same time, by setting the first notch 64 and the second notch 65, the extension portion 60 of the collecting plate 200 partially avoids the first clamping portion 151 and the second clamping portion 152, so that the extension portion 60 of the collecting plate 200 can be clamped into the receiving groove 13 more easily.

[0097] By bending the connection portion 50 of the current collecting disk 200, the disk body 40 can be bent relative to the extension portion 60, and along the thickness direction of the insulating component 10, the disk body 40 covers the second surface 112 of the main body 11, and the extension portion 60 is located between the disk body 40 and the main body 11. When the positioning column 14 is flush with the second surface 112 of the main body 11 or protrudes from the second surface 112, the second surface 112 of the main body 11 and the positioning column 14 can support the disk body 40 of the current collecting disk 200. It should be noted that in this embodiment, along the thickness direction of the insulating component 10, the orthographic projection of the disk body 40 is located within the orthographic projection of the insulating component 10. The area of the disk body 40 is smaller than the area of the second surface 112, and the disk body 40 covers most of the second surface 112, but does not completely cover the second surface 112.

[0098] It can be understood that when the extension part 60 of the current collector plate 200 is assembled to the insulating part 10, the positioning post 14 in the accommodation groove 13 of the insulating part 10 can limit the extension part 60 of the current collector plate 200; during the process of bending the current collector plate 200, the positioning post 14 can prevent the current collector plate 200 from being misaligned and shaking. The disk body part 40 moves towards the extension part 60, causing the connecting part 50 to bend. This bending angle causes the bending force to be transmitted to the extension part 60, driving the extension part 60 to tilt away from the accommodation groove 13. The positioning post 14 can limit the degree to which the extension part 60 of the current collector plate 200 tilts away from the accommodation groove 13 due to the bending operation of the current collector plate 200 to the maximum extent. In addition, since the diameter of the positioning hole 63 of the extension part 60 of the current collector plate 200 is larger than the diameter of the positioning post 14 of the insulating part 10, and the difference between the diameter of the positioning hole 63 and the diameter of the positioning post 14 is 0.5 mm - 1.0 mm, a certain assembly gap is reserved in the positioning hole 63 of the extension part 60, facilitating the positioning post 14 of the insulating part 10 to pass through the positioning hole 63 of the extension part 60. The end of the positioning post 14 is provided with a chamfer, which can prevent the end face of the positioning post 14 from scratching the extension part 60 of the current collector plate 200 when the positioning post 14 is inserted into the positioning hole 63 of the extension part 60 of the current collector plate 200. Since the area of the end face of the free end of the positioning post 14 is smaller than the cross-sectional area away from the free end, it is convenient for the positioning post 14 of the insulating part 10 to pass through the positioning hole 63 of the extension part 60.

[0099] By limiting the minimum diameter of the positioning post 14 to 1.5 mm, it can be avoided that the small diameter of the positioning post 14 results in low strength of the positioning post 14, preventing the edge of the positioning hole 63 of the extension part 60 from breaking the positioning post 14 when the extension part 60 tilts away from the accommodation groove 13. By limiting the maximum diameter of the positioning post 14 to 3.0 mm, it can be avoided that the positioning hole 63 corresponding to the positioning post 14 on the extension part 60 is too large, thereby avoiding that the distance between adjacent positioning holes 63 on the extension part 60 is too narrow, resulting in low strength of the extension part 60, and preventing the extension part 60 from cracking or even breaking due to the force exerted by the positioning post 14 on the extension part 60 when the extension part 60 tilts away from the accommodation groove 13.

[0100] Since the positioning posts 14 on the insulating component 10 are arranged in a staggered manner, the positioning holes 63 of the extension portion 60 of the current collector plate 200 are also arranged in a staggered manner. On the one hand, it can avoid the excessive stress concentration around the positioning hole 63 caused by the stretching force when the extension portion 60 of the current collector plate 200 is lifted away from the accommodating groove 13 due to the bending operation of the current collector plate 200, thereby avoiding the extension portion 60 of the current collector plate 200 from cracking and breaking at the positioning hole 63 during the bending process, which affects the service life of the energy storage device 1000. On the other hand, it has a certain anti-fooling function. Only when the staggered positioning posts 14 and the staggered positioning holes 63 are in one-to-one correspondence in position can it be ensured that the third surface 411 of the current collector plate 200 provided with the welding protrusion 42 faces the direction of the ear 320, preventing the current collector plate 200 from being placed in the wrong direction and resulting in inability to weld with the fallen ear.

[0101] Please refer to Figure 14 , Figure 14 is Figure 2 the structural schematic diagram of the second embodiment of the current collector plate shown. The difference between the second embodiment and the first embodiment lies in the structure of the positioning hole 63 of the extension portion 60 of the current collector plate 200.

[0102] A plurality of limiting pieces 631 are provided in the positioning hole 63 of the extension portion 60, and the plurality of limiting pieces 631 extend from the hole wall of the positioning hole 63 towards the axis direction of the positioning hole 63. Specifically, the plurality of limiting pieces 631 are flat sheets. The plurality of limiting pieces 631 are arranged at intervals around the axis of the positioning hole 63. The end portions of the plurality of limiting pieces 631 away from the hole wall of the positioning hole 63 form a through hole 632. The aperture of the through hole 632 is smaller than the diameter of the positioning post 14. In this embodiment, the number of the limiting pieces 631 is 6. The limiting piece 631 is an elastic body. Specifically, the limiting piece 631 is a metal thin sheet with elasticity. The limiting piece 631 and the extension portion 60 are integrally formed.

[0103] In this embodiment, along the width direction of the extension portion 60, the extension portion 60 includes two opposite side edges. The number of the positioning holes 63 is 2, and the positioning holes 63 are arranged in a staggered manner along the width direction of the extension portion 60. That is, the two positioning holes 63 are respectively close to the two opposite side edges of the extension portion 60. Among the plurality of limiting pieces 631 in each positioning hole 63, the extension direction of the limiting piece 631a with the shortest distance from the side edge of the extension portion 60 close to each positioning hole 63 is perpendicular to the length direction of the extension portion 60. In other embodiments, in each positioning hole 63, it may also be that the gap between two adjacent limiting pieces 631 has the shortest distance from the side edge of the extension portion 60 close to each positioning hole 63.

[0104] Figure 15 is Figure 2 the end cover assembly shown and Figure 14Schematic diagram of the assembly process of the current collector plate of the second embodiment shown. The extension portion 60 of the current collector plate 200 is received in the receiving groove 13 of the insulating member 10. Along the thickness direction of the insulating member 10, the positioning post 14 in the receiving groove 13 of the insulating member 10 penetrates through the positioning hole 63 of the extension portion 60. When the positioning post 14 of the insulating member 10 is inserted into the positioning hole 63 of the extension portion 60, since the aperture of the through hole 632 formed by the plurality of limiting pieces 631 is smaller than the outer diameter of the positioning post 14, the positioning post 14 applies a force to the limiting pieces 631 in the direction away from the receiving groove 13, causing the limiting pieces 631 to elastically deform and bend in the direction away from the receiving groove 13; during the process of the positioning post 14 passing through the positioning hole 63 and after the positioning post 14 passes through the positioning hole 63, the limiting pieces 631 have an elastic resilience force that will continuously abut against the circumferential side surface of the positioning post 14, and a frictional force is generated between the limiting pieces 631 and the circumferential side surface of the positioning post 14, which plays a positioning role for the positioning post 14. During the bending process of the connecting portion 50 of the current collector plate 200, the disk body portion 40 moves towards the extension portion 60, causing the connecting portion 50 to bend. This bending angle will transmit the bending force to the extension portion 60, driving the extension portion 60 to tilt away from the receiving groove 13. At this time, the limiting pieces 631 will also move in the direction away from the receiving groove 13. Since the positioning post 14 is a plastic part and the limiting pieces 631 are metal sheets, the end portion of the limiting piece 631 abuts against the circumferential side surface of the positioning post 14, and the end portion of the limiting piece 631 presses against the circumferential side surface of the positioning post 14 to form a notch. The end portion of the limiting piece 631 that abuts against the positioning post 14 will be stuck in the notch, and thus the positioning post 14 can hinder the movement of the limiting piece 631, thereby preventing the extension portion 60 from continuing to tilt away from the receiving groove 13, improving the stability of the extension portion 60 assembled to the insulating member 10.

[0105] Since along the width direction of the extension portion 60, the extending direction of one limiting piece 631a with the shortest distance from the side of the extension portion 60 is perpendicular to the length direction of the extension portion 60, this limiting piece 631 forms the fusing portion of the current collector plate 200. When the energy storage device 1000 has extreme charging and discharging or a short circuit occurs, resulting in an excessive current, the limiting piece 631 and the side of the extension portion 60 will fuse first, that is, along the width direction of the extension portion 60, a crack is formed between the limiting piece 631 and the side of the extension portion 60.

[0106] In this embodiment, the number of positioning holes 63 is 2, and the two positioning holes 63 are respectively close to the two sides of the extension portion 60. As Figure 15, a limiting piece 631a in a positioning hole 63 extends along the width direction of the extension part 60, and the extension direction is perpendicular to the length direction of the extension part 60, and the distance from the side of the extension part 60 is the shortest. A crack will be formed by fusing between the limiting piece 631a and the side of the extension part 60. Subsequently, since the current on the current collector plate 200 is mainly concentrated between the two positioning holes 63, cracks will also be formed by fusing between the two positioning holes 63. At this time, a crack penetrating the extension part 60 along the width direction of the extension part 60 is formed on the extension part 60, and the extension part 60 is in an open circuit state, so that the entire energy storage device 1000 is in an open circuit state, avoiding overheating inside the energy storage device 1000 caused by excessive current and ensuring the safety of the energy storage device 1000 during use.

[0107] Please refer to Figure 16 , Figure 16 is Figure 2 a schematic structural diagram of the third embodiment of the current collector plate shown. The difference between the third embodiment and the second embodiment lies in the shape of the limiting piece 631.

[0108] In this embodiment, a plurality of limiting pieces 631 protrude from the hole wall of the positioning hole 63, and the plurality of limiting pieces 631 extend from the hole wall of the positioning hole 63 towards the axis direction of the positioning hole 63. Specifically, the plurality of limiting pieces 631 are curved sheets. A plurality of limiting pieces 631 protrude from the hole wall of the positioning hole 63, and each limiting piece 631 bends and extends from the first surface 61 of the extension part 60 towards the second surface 62. The extension trajectories of the plurality of limiting pieces 631 are arc-shaped. The end portions of the plurality of limiting pieces 631 far from the hole wall of the positioning hole 63 form a through hole 632. The aperture of the second through hole 632 is smaller than the diameter of the positioning post 14.

[0109] As Figure 15 , which also shows Figure 2 the assembly process schematic diagram of the end cover assembly shown and Figure 16 the current collector plate of the third embodiment shown. The extension part 60 of the current collector plate 200 is accommodated in the accommodation groove 13 of the insulating member 10. Along the thickness direction of the insulating member 10, the positioning post 14 in the accommodation groove 13 of the insulating member 10 penetrates through the positioning hole 63 of the extension part 60. When the positioning post 14 of the insulating member 10 is inserted into the positioning hole 63 of the extension part 60, the positioning post 14 of the insulating member 10 first abuts against the surface of the plurality of limiting pieces 631 facing the first surface 61 of the extension part 60, and then the positioning post 14 can slide along the surface of the plurality of limiting pieces 631 in a direction perpendicular to the positioning hole 63 until the positioning post 14 completely passes through the positioning hole 63. Therefore, the plurality of limiting pieces 631 in the positioning hole 63 of the extension part 60 are in a bent state, and the bending direction is along the passing direction of the positioning post 14, which can guide the positioning post 14 to pass through the positioning hole 63, and the plurality of limiting pieces 631 have elastic resilience and will abut against the outer peripheral surface of the positioning post 14 to limit the positioning post 14.

[0110] In addition, during the bending process of the connecting portion 50 of the current collector plate 200, the disk body portion 40 moves towards the extending portion 60, causing the connecting portion 50 to bend. This bending angle causes the bending force to be transmitted to the extending portion 60, driving the extending portion 60 to tilt away from the accommodating groove 13. At this time, the limiting piece 631 also moves away from the accommodating groove 13 accordingly. Since the positioning post 14 is a plastic part and the limiting piece 631 is a metal piece, the end of the limiting piece 631 abuts against the circumferential side surface of the positioning post 14, and the end of the limiting piece 631 presses against the circumferential side surface of the positioning post 14 to form a notch. The end of the limiting piece 631 in contact with the positioning post 14 will be stuck in the notch. Furthermore, the positioning post 14 can hinder the movement of the limiting piece 631, thereby preventing the extending portion 60 from tilting further away from the accommodating groove 13, improving the stability of the extending portion 60 assembled to the insulating component 10.

[0111] Please refer to Figure 17 , Figure 17 is Figure 2 a schematic structural view of the fourth embodiment of the current collector plate shown. The difference between the fourth embodiment and the first embodiment lies in the structure of the positioning hole 63 of the extending portion 60 of the current collector plate 200.

[0112] In this embodiment, the limiting piece 631 in the positioning hole 63 is formed by cutting a slit along the radial direction of the hole wall of the positioning hole 63, and there is a slit 634 between every two limiting pieces 631. It can be understood that the slit extends towards the extending portion 60 around the positioning hole 63 and does not cut off the side of the extending portion 60, that is, the positioning hole 63 containing the limiting piece 631 has a certain distance from the side of the extending portion 60. Along the thickness direction of the extending portion 60, a plurality of slits 634 penetrate through the first surface 61 and the second surface 62 of the extending portion 60. The plurality of slits 634 are arranged at intervals around the axis of the positioning hole 63. In this embodiment, the number of slits 634 is 4, and correspondingly, the number of limiting pieces 631 is also 4. The limiting piece 631 is an elastic body. Specifically, the limiting piece 631 can be an elastic metal thin sheet. The limiting piece 631 and the extending portion 60 are integrally formed.

[0113] Figure 18 is Figure 2 the shown end cap assembly and Figure 17Schematic diagram of the assembly process of the current collector plate of the fourth embodiment shown. The extension portion 60 of the current collector plate 200 is received in the receiving groove 13 of the insulating member 10. Along the thickness direction of the insulating member 10, the positioning post 14 in the receiving groove 13 of the insulating member 10 penetrates through the positioning hole 63 of the extension portion 60. When the positioning post 14 of the insulating member 10 is inserted into the positioning hole 63 of the extension portion 60, even if the positioning post 14 is not coaxially opposed to the positioning hole 63, the positioning post 14 can cause any one of the limiting pieces 631 in the positioning hole 63 to elastically deform and bend in a direction away from the receiving groove 13. At this time, the limiting piece 631 guides the movement of the positioning post 14, and the positioning post 14 can slide along the surface of the limiting piece 631 and pass through the positioning hole 63. When the positioning post 14 and the positioning hole 63 are coaxially arranged, the limiting piece 631 rebounds and returns to its initial state. Therefore, by cutting slits along the radial direction of the positioning hole 63 in the hole wall of the positioning hole 63 to form a plurality of limiting pieces 631, the alignment accuracy between the positioning post 14 and the positioning hole 63 can be reduced, thereby reducing the process difficulty.

[0114] Please refer to Figure 19 , Figure 19 is Figure 2 Schematic diagram of the structure of the fifth embodiment of the current collector plate shown. The difference between the fifth embodiment and the first embodiment lies in the structure of the positioning hole 63 of the extension portion 60 of the current collector plate 200.

[0115] In this embodiment, a convex ring 638 is provided at the edge of the positioning hole 63 of the extension portion 60. The convex ring 638 protrudes from the second surface 62 of the extension portion 60 and extends in a direction away from the second surface 62 of the extension portion 60. The convex ring 638 surrounds the edge of the positioning hole 63. In this embodiment, the convex ring 638 is circular, and the convex ring 638 is made of metal. The convex ring 638 and the extension portion 60 are integrally formed. The convex ring 638 of this embodiment is applicable to the positioning hole 63 of any of the above embodiments, and the inner diameter formed by the inner diameter of the convex ring 638 and the actual hole wall of the positioning hole 63 is the same.

[0116] Figure 20 is Figure 2 shown end cap assembly and Figure 19Schematic diagram of the assembly process of the current collector plate of the fifth embodiment shown. The extension portion 60 of the current collector plate 200 is received in the receiving groove 13 of the insulating member 10. Along the thickness direction of the insulating member 10, the positioning post 14 in the receiving groove 13 of the insulating member 10 passes through the positioning hole 63 of the extension portion 60. During the bending process of the connecting portion 50 of the current collector plate 200, the disk body portion 40 moves towards the extension portion 60 to bend the connecting portion 50, and this bending angle causes the bending force to be transmitted to the extension portion 60, driving the extension portion 60 to tilt away from the receiving groove 13. Since the positioning post 14 is made of plastic and has slight elasticity, and the current collector plate 200 is made of metal, during the tilting process of the extension portion 60, the edge of the positioning hole 63 of the extension portion 60 presses against the positioning post 14. By adding a convex ring 638 to the edge of the positioning hole 63, the contact area between the edge of the positioning hole 63 and the positioning post 14 can be increased, the pressure received by the positioning post 14 can be reduced, and further the deformation amount of the positioning post 14 can be reduced, ensuring the limiting effect of the positioning post 14 on the extension portion 60; avoiding that due to the thin edge of the positioning hole 63 and the small contact area between the edge of the positioning hole 63 and the positioning post 14, the pressure received by the positioning post 14 is large; and further avoiding that the deformation amount of the positioning post 14 is large or even broken by the edge of the positioning hole 63, affecting the limiting effect of the positioning post 14 on the extension portion 60.

[0117] Please refer to Figure 21 , Figure 21 is Figure 2The schematic diagram of partial structural decomposition of the energy storage device shown. The end cover assembly 100 also includes an upper plastic 30, a pressing block 70, a pole 80 and a sealing ring 90. Specifically, the upper plastic 30 and the top cover 20 are stacked, and the upper plastic 30 is located on the side of the top cover 20 away from the insulating component 10. A through hole 31 is provided on the upper plastic 30 for the pole 80 to pass through. The pressing block 70 is stacked on the side of the upper plastic 30 away from the top cover 20 and is fixedly connected to the upper plastic 30. Among them, the pole 80 includes a column 81 and a flange portion 82. Along the thickness direction of the end cover assembly 100, the column 81 of the pole 80 is sequentially penetrated through the pole through hole 114 of the insulating component 10, the pole hole 211 of the top cover 20, and the through hole 31 on the upper plastic 30, and is fixedly connected to the pressing block 70. The flange portion 82 of the pole 80 is crimped to the second surface 112 of the insulating component 10. The end cap assembly 100 and the electrode assembly 300 are connected by the current collecting disk 200, and the current collecting disk 200 is located between the end cap assembly 100 and the electrode assembly 300. The extension portion 60 of the current collecting disk 200 is accommodated in the accommodating groove 13 of the insulating component 10, and the extension portion 60 of the current collecting disk 200 is fixedly connected to the flange portion 82 of the pole 80. The disk body 40 of the current collecting disk 200 is fixedly connected to the pole lug 320 of the electrode assembly 300. The sealing ring 90 is assembled on the pole 80 of the pole 80 near the end of the flange portion 82. In this embodiment, the extension portion 60 of the current collecting disk 200 is connected to the flange portion 82 of the pole 80 by welding, and the disk body 40 of the current collecting disk 200 is connected to the pole lug 320 of the electrode assembly 300 by welding.

[0118] The assembly process of the energy storage device 1000 provided in the embodiment of the present application is as follows: first, the end cap assembly 100, the electrode assembly 300, the current collecting plate 200 and the shell 400 are respectively manufactured; secondly, the extension portion 60 of the current collecting plate 200 is clamped in the accommodating groove 13 through the first clamping portion 151 and the second clamping portion 152 of the insulating component 10, and the end of the extension portion 60 of the current collecting plate 200 is welded and fixed to the flange portion 82 of the pole 80; thirdly, the disc portion 40 of the current collecting plate 200 is connected to the electrode assembly The pole ear 320 of 300 is welded and fixed; then, the connecting portion 50 of the collecting plate 200 is bent so that the disc body 40 of the collecting plate 200 is overlapped on the side of the extending portion 60 of the collecting plate 200 facing away from the insulating component 10, and the end cover assembly 100 is basically coaxial with the electrode assembly 300; finally, the electrode assembly 300 is placed in the shell 400, so that the end cover assembly 100 covers the opening of the shell 400 and seals it, and the disc body 40 of the collecting plate 200 is connected to the electrode assembly 300 through the opening.

[0119] It can be understood that after the extension part 60 of the current collector plate 200 is connected to the pole column 80 of the end cover assembly 100 and the disk body part 40 of the current collector plate 200 is connected to the tab 320 of the electrode assembly 300, the bending process of the current collector plate 200 can make the extension part 60 and the disk body part 40 partially overlap along the height direction of the energy storage device 1000. Compared with the extension part 60 and the disk body part 40 being in the same plane, the occupied space of the current collector plate 200 inside the energy storage device 1000 can be reduced, the space utilization rate of the energy storage device 1000 can be improved, and thus the energy density of the energy storage device 1000 can be further improved. Through the mutual cooperation between the positioning post 14 on the insulating part 10 and the positioning hole 63 of the extension part 60 of the current collector plate 200, the positioning post 14 of the insulating part 10 can limit the extension part 60 of the current collector plate 200; at the same time, during the bending process of the current collector plate 200, the positioning post 14 of the insulating part 10 can limit the degree to which the extension part 60 of the current collector plate 200 is driven to tilt upward due to the bending operation, thereby avoiding the fracture at the welding edge of the end of the extension part 60 of the current collector plate 200 and the flange part 82 of the pole column 80, ensuring the connection reliability between the end of the extension part 60 of the current collector plate 200 and the flange part 82 of the pole column 80, making the bending process faster and more labor-saving, and further improving the yield rate and efficiency of mass production.

[0120] The embodiments of the present application have been introduced in detail above. Specific examples are used in this article to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those of ordinary skill in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. An end cap assembly is applied to an energy storage device (1000). The energy storage device (1000) includes a current collector plate (200) and an electrode assembly (300). The current collector plate (200) includes an extension portion (60) and a plate body portion (40). The extension portion (60) is connected to the plate body portion (40), and is characterized in that, Two positioning holes (63) are provided on the extension part (60), and in the thickness direction of the extension part (60), the two positioning holes (63) penetrate through the extension part (60); The end cover assembly (100) includes an insulating part (10), the insulating part (10) includes a body part (11), the body part (11) has a first surface (111) and a second surface (112), and the first surface (111) and the second surface (112) are arranged opposite to each other; The insulating part (10) further includes a receiving groove (13), and the receiving groove (13) is recessed in the second surface (112) of the body part (11); The insulating part (10) further includes two positioning posts (14), and the two positioning posts (14) protrude from the bottom wall (134) of the receiving groove (13). Along the length direction of the receiving groove (13), the two positioning posts (14) are arranged in a staggered manner; The extension part (60) is received in the receiving groove (13), and each positioning post (14) passes through one positioning hole (63); the disc part (40) is bent relative to the extension part (60), and in the thickness direction of the insulating part (10), the disc part (40) covers the second surface (112); The end cover assembly (100) is connected to the electrode assembly (300), the current collecting disc (200) is located between the end cover assembly (100) and the electrode assembly (300), and the disc part (40) is connected to the electrode assembly (300).

2. The end cap assembly according to claim 1, characterized in that, The end faces of the two positioning posts (14) facing away from the receiving groove (13) are flush with the second surface (112), and the second surface (112) and the positioning posts (14) support the disc part (40).

3. The end cap assembly according to claim 1, characterized in that The positioning post (14) is a cylinder with a diameter of 1.5 mm - 3.0 mm.

4. The end cap assembly according to claim 1, characterized in that, The positioning post (14) includes an end face facing away from the receiving groove (13) and a circumferential side face connected to the end face. A chamfer is formed at the connection between the end face of the positioning post (14) and the circumferential side face of the positioning post (14), and the chamfer is inclined from the end face of the positioning post (14) towards the circumferential side face of the positioning post (14).

5. The end cap assembly according to claim 1, wherein From the bottom wall (134) of the receiving groove (13) towards the second surface (112), the cross-sectional area of the positioning post (14) gradually decreases.

6. The end cap assembly according to any one of claims 1-5, characterized in that, The insulating component (10) further includes a first clamping portion (151) and a second clamping portion (152). The first clamping portion (151) and the second clamping portion (152) are respectively arranged on two opposite groove side walls of the accommodation groove (13). There is a gap between the first clamping portion (151) and the second clamping portion (152) and the bottom wall (134) of the accommodation groove (13). Along the thickness direction of the end cover assembly (100), the extension portion (60) is limited in the gaps between the first clamping portion (151) and the bottom wall (134) of the accommodation groove (13), and between the second clamping portion (152) and the bottom wall (134) of the accommodation groove (13).

7. The end cap assembly according to claim 6, wherein The main body portion (11) includes a peripheral side surface (113) connecting the first surface (111) and the second surface (112). The peripheral side surface (113) has a notch (135). Along the length direction of the accommodation groove (13), the notch (135) communicates with the accommodation groove (13); the first clamping portion (151) and the second clamping portion (152) are located on opposite sides of the notch (135).

8. An energy storage device, characterized in that, It includes a housing (400), an electrode assembly (300), a current collecting plate (200) and the end cover assembly (100) according to any one of claims 1-7. The housing (400) has an opening. The housing (400) is provided with an accommodation cavity. The electrode assembly (300) is accommodated in the accommodation cavity. The end cover assembly (100) covers the opening. The disc portion (40) is connected to the electrode assembly (300) through the opening.

9. The energy storage device according to claim 8, wherein, The current collecting plate (200) further includes a connecting portion (50). The connecting portion (50) connects the disc portion (40) and the extension portion (60). The connecting portion (50) is made of a flexible material. By bending the connecting portion (50), the disc portion (40) can be bent relative to the extension portion (60).

10. The energy storage device according to claim 8, characterized in that, The positioning hole (63) is circular. The aperture of the positioning hole (63) is larger than the diameter of the positioning post (14). The difference between the aperture of the positioning hole (63) and the diameter of the positioning post (14) is 0.5 mm - 1.0 mm.

11. The energy storage device according to claim 8, wherein A plurality of limiting pieces (631) are arranged in the positioning hole (63). The plurality of limiting pieces (631) extend from the hole wall of the positioning hole (63) towards the axis direction of the positioning hole (63), and the plurality of limiting pieces (631) are arranged at intervals around the axis of the positioning hole (63); the ends of the plurality of limiting pieces (631) far from the hole wall of the positioning hole (63) form a through hole (632). The aperture of the through hole (632) is smaller than the diameter of the positioning post (14).

12. The energy storage device according to claim 8, wherein A plurality of limiting pieces (631) are provided in the positioning hole (63). The plurality of limiting pieces (631) are formed by cutting slits along the radial direction of the hole wall of the positioning hole (63). And there is a slit (634) between every two of the limiting pieces (631). Along the thickness direction of the extension part (60), the slit (634) penetrates through two opposite surfaces of the extension part (60).

13. The energy storage device according to claim 11, characterized in that, The extension part (60) includes a first surface (61) and a second surface (62). Along the thickness direction of the extension part (60), the first surface (61) and the second surface (62) are arranged back to back. The plurality of limiting pieces (631) protrude from the hole wall of the positioning hole (63) and are arranged at intervals around the axis of the positioning hole (63); each of the limiting pieces (631) bends and extends from the first surface (61) towards the second surface (62).

14. The energy storage device according to any one of claims 11 or 13, characterized in that, The positioning post (14) is a plastic part, and the limiting piece (631) is a metal piece. The end of the limiting piece (631) abuts against the peripheral side surface of the positioning post (14), and the end of the limiting piece (631) presses against the peripheral side surface of the positioning post (14) to form a notch.

15. The energy storage device according to claim 11, wherein, Along the width direction of the extension part (60), the extension part (60) includes two opposite side edges. The number of the positioning holes (63) is two. Along the width direction of the extension part (60), the two positioning holes (63) are arranged in a staggered manner. And among the plurality of limiting pieces (631) in each positioning hole (63), the extending direction of the limiting piece (631) with the shortest distance to the side edge of the extension part (60) is perpendicular to the length direction of the extension part (60).

16. The energy storage device according to claim 8, wherein A convex ring (638) protrudes from the second surface (62) of the extension part (60). The convex ring (638) surrounds the edge of the positioning hole (63).

17. The energy storage device according to claim 8, characterized in that, The disc body part (40) includes a body (41) and welding protrusions (42). The body (41) has a central axis. The welding protrusions (42) protrude from the surface of the body (41) and are evenly distributed around the central axis.

18. An electrical device, characterized in that, It includes the energy storage device (1000) according to any one of claims 8-17. The energy storage device (1000) is used to supply power to an electrical device.

19. A household energy storage system, characterized in that, It includes the energy storage device (1000) according to any one of claims 8-17, a power conversion device (4000) and a user load. The energy storage device (1000) stores the electric energy of the power conversion device (4000) and transmits the electric energy to the user load.

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