End cover assembly and manufacturing method thereof, energy storage device and electric equipment

Abstract

The invention discloses an end cover assembly and a manufacturing method thereof, an energy storage device and electric equipment, the end cover assembly comprises an end cover, lower plastic, a pole and a sealing ring, the end cover is provided with a through hole, the lower plastic comprises a pole through hole, the lower plastic and the end cover are stacked along the thickness direction of the end cover assembly, and the through hole is communicated with the pole through hole. The pole comprises a pole body, a flange and a folding part, the folding part and the flange are oppositely arranged at an interval along the height direction of the pole, the pole body comprises a mounting surface opposite to the flange, the folding part is convexly arranged on the periphery of one end of the pole body and surrounds the mounting surface, the folding part comprises an appearance surface connected to the mounting surface, and a crease is arranged between the appearance surface and the mounting surface. The appearance surface is flush with the mounting surface, or the mounting surface protrudes out of the appearance surface in the direction from the folding part to the flange; the sealing ring is sleeved on the periphery of the pole and penetrates through the through hole and the pole through hole together with the pole, the end cover part on the periphery of the through hole is positioned between the flange and the turnover part, and the flange, the lower plastic, the end cover and the turnover part jointly clamp the sealing ring.

Description

Technical Field

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

[0002] With the development of secondary energy storage technology and the increase in demand, people's requirements for the reliability of energy storage devices are gradually increasing, especially the reliability of the end cap assembly in the energy storage device. The sealing structure of the existing end cap assembly is complex. For example, the end cap assembly includes upper plastic, lower plastic and sealing ring and other structural parts for sealing. There are many assembly gaps between them, and the sealing performance is reduced in low temperature environment. It is even easy to have the problem of sealing failure, which greatly reduces the reliability of the end cap assembly. Summary of the invention

[0003] The present application provides an end cover assembly and a manufacturing method thereof, an energy storage device and an electrical equipment, which can improve the reliability of the end cover assembly.

[0004] The present application provides an end cap assembly, the end cap comprising:

[0005] The end cover is provided with a through hole, and the through hole penetrates two surfaces of the end cover in the thickness direction.

[0006] The lower plastic comprises a pole through hole, the pole through hole penetrates two surfaces of the lower plastic in the thickness direction, the lower plastic and the end cover are stacked along the thickness direction of the end cover assembly, and the through hole is connected to the pole through hole.

[0007] A pole, the pole comprising a pole body and a flange, the flange being connected to one end of the pole body in the height direction, the pole body comprising a mounting surface, the mounting surface facing away from the flange, the pole further comprising a folding portion, the folding portion being protruded from the periphery of one end of the pole body and surrounding the mounting surface, the folding portion and the flange being opposite and spaced apart along the height direction of the pole, the folding portion comprising an appearance surface, the appearance surface facing away from the flange and connected to the mounting surface, a fold being provided between the appearance surface and the mounting surface, the appearance surface being flush with the mounting surface, or, along the direction from the folding portion to the flange, the mounting surface protrudes from the appearance surface. And

[0008] A sealing ring is sleeved on the outer circumference of the pole body and penetrates the through hole and the pole through hole together with the pole. The end cover portion of the through hole periphery is located between the flange and the folded portion. The flange, the lower plastic, the end cover and the folded portion jointly clamp the sealing ring, and the end cover, the lower plastic and the pole compress the sealing ring.

[0009] In one embodiment, the lower plastic includes a bottom surface and a top surface, the top surface and the bottom surface are arranged opposite to each other along the thickness direction of the lower plastic, the lower plastic includes an avoidance groove, the avoidance groove is recessed in the top surface and recessed toward the bottom surface, and the pole through hole passes through the bottom wall of the avoidance groove.

[0010] The end cover comprises a first surface and a second surface, the first surface and the second surface are arranged opposite to each other along the thickness direction of the end cover, and the through hole passes through the second surface and the first surface.

[0011] The notch of the avoidance groove is opposite to the end cover, and there is a gap between the groove bottom wall of the avoidance groove and the second surface of the end cover at the periphery of the through hole, and the gap is connected to the pole through hole and the through hole.

[0012] The portion of the sealing ring clamped between the lower plastic and the end cover extends into the gap.

[0013] In one embodiment, the sealing ring includes a first section, a second section and a third section, the second section is connected to the first section and the third section, the second section extends along the axial direction of the sealing ring, the third section and the first section both extend away from the axis of the sealing ring, and the first section and the third section are both straight sections.

[0014] The second section is connected to the pole body and the end cover, the end cover around the pole is located between the first section and the third section, the end cover and the first section and the third section are clamped by the folded portion and the flange, the third section is at least partially accommodated in the gap, and blocks the assembly gap between the pole and the lower plastic.

[0015] In one embodiment, the contact area between the third section and the end cover is greater than the contact area between the first section and the end cover.

[0016] In one embodiment, the flange protrudes from the bottom surface of the lower plastic, and the folded portion is located on a side of the end cover facing away from the lower plastic.

[0017] The first section is clamped between the folded portion and the end cover, and the outer circumferential surface of the first section is protruded compared to the outer circumferential surface of the folded portion. The third section is clamped between the flange and the end cover, and the outer circumferential surface of the third section is protruded compared to the outer circumferential surface of the flange.

[0018] In one embodiment, the appearance surface of the folded portion is oriented in the same direction as the bottom surface of the lower plastic, and the flange is located on a side of the end cover facing away from the lower plastic.

[0019] The first section is clamped between the flange and the end cover, and the outer circumference of the first section is protruding compared to the outer circumference of the flange. The third section is clamped between the folded portion and the end cover, and the outer circumference of the third section is protruding compared to the outer circumference of the folded portion.

[0020] In one embodiment, the end cover further includes a sealing groove, which is recessed in the second surface of the end cover and recessed in the direction of the first surface, and the through hole penetrates the bottom wall of the sealing groove.

[0021] The notch of the avoidance groove is opposite to the notch of the sealing groove, and the gap is formed between the bottom wall of the avoidance groove and the bottom wall of the sealing groove. The gap is connected to the pole through hole and the through hole, and the third section is connected to the bottom wall of the sealing groove and the bottom wall of the avoidance groove.

[0022] In one embodiment, the first section has a first compression amount after compression, and the third section has a second compression amount after compression, and the sum of the first compression amount and the second compression amount is 5% to 55% of the sum of the thicknesses of the first section and the third section before compression.

[0023] In one embodiment, the flange includes a connecting surface, which surrounds and connects the pole body. The flange also includes a step, which is located on the outer peripheral surface of the flange and is recessed in the connecting surface. The step includes an assembly surface, the orientation of the assembly surface is consistent with the orientation of the connecting surface, and the assembly surface abuts against the bottom surface of the lower plastic.

[0024] In one embodiment, the pole further includes a protrusion, which is protruded from the mounting surface of the pole body and located in the middle of the mounting surface. Along a direction perpendicular to the axis of the pole, the protrusion is spaced apart from the folded portion.

[0025] In one embodiment, the present application provides a method for manufacturing an end cap assembly, which is used to manufacture the end cap assembly, and the manufacturing method includes:

[0026] Providing a sealing ring before assembly, and providing an extending direction of a first section and an extending direction of a second section of the sealing ring before assembly;

[0027] A pole before assembly is provided, wherein a mounting surface of the pole body before assembly is provided with a protrusion, the pole before assembly comprises a folding portion base, the folding portion base is arranged around the periphery of the pole body, and the folding portion base protrudes from the mounting surface of the pole body, a groove is formed between the folding portion base and the protrusion, the folding portion comprises an inner annular surface, the inner annular surface is connected to the mounting surface and is arranged at an angle with the mounting surface, and the extension direction of the folding portion base is the same as the axial direction of the pole before assembly;

[0028] The lower plastic and the end cover are stacked, and the pole through hole of the lower plastic and the through hole of the end cover are coaxial and connected;

[0029] The pole before assembly is passed through the sealing ring before assembly, and passes through the pole through hole and the through hole in sequence with the sealing ring before assembly, the flange protrudes from the lower plastic, the third section is clamped between the end cover and the flange, the folded portion base and the first section protrude from the end cover, the first section and the folded portion base extend in the same direction, and the second section is connected between the end cover and the pole body;

[0030] The folding portion base is flipped away from the end cover, and the first section is pressed toward the end cover, so that the folding portion base forms the folding portion, the inner annular surface forms the appearance surface, the folding portion and the end cover clamp the first section, and the appearance surface is flush with the mounting surface.

[0031] The present application provides an energy storage device, which includes a shell, an electrode assembly and an end cap assembly. The electrode assembly is mounted on the shell, and the end cap assembly is mounted on one end of the electrode assembly and seals the shell.

[0032] The present application provides an electrical device, wherein the electrical device comprises the energy storage device, and the energy storage device supplies power to the electrical device.

[0033] In the related art, the sealing structure in the end cap assembly is complex. For example, the end cap assembly includes upper plastic, lower plastic, and sealing rings and other structural parts for sealing. The sealing performance of these structural parts for sealing will decrease in low temperature environments, and even the problem of sealing failure is easy to occur, which can easily reduce the reliability of the end cap assembly. For example, the structural parts for sealing in the existing end cap assembly are generally made of fluororubber, which is easy to become brittle in low temperature environments (-40°C), causing the sealing performance of the end cap assembly to fail, resulting in poor performance of the energy storage device.

[0034] In the embodiment of the present application, the structure of the end cap assembly is simple, and only the first sealing ring and the second sealing ring are used as the structural parts for sealing in the end cap assembly. In addition, the sealing ring can cover the gap between the end cap, the lower plastic and the pole, and can be used as the upper plastic to cooperate with the end cap to reduce the assembly gap and improve the sealing performance. At the same time, the end cap assembly of this embodiment omits the upper plastic, which saves the production cost of the end cap assembly and simplifies the structure of the end cap assembly. The materials of the first sealing ring and the second sealing ring are both made of rubber synthetic materials that are resistant to low temperatures and electrolytes, so that the end cap assembly can maintain good sealing performance even at low temperatures, thereby improving the reliability of the end cap assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] 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 from these drawings without paying any creative work.

[0036] Figure 1 An application scenario diagram of the energy storage device provided in the embodiment of the present application;

[0037] Figure 2 for Figure 1 A schematic diagram of the structure of the energy storage device shown;

[0038] Figure 3 for Figure 2 The schematic structural diagram of the first embodiment of the end cover assembly of the energy storage device shown;

[0039] Figure 4 for Figure 3 An exploded schematic diagram of the end cap assembly shown;

[0040] Figure 5 for Figure 4 An exploded schematic diagram of the end cap assembly shown in another angle;

[0041] Figure 6 for Figure 4 A cross-sectional view of a first sealing ring and a second sealing ring of the end cap assembly shown;

[0042] Figure 7 for Figure 4 A cross-sectional view of a first embodiment of a first pole and a second pole of an end cap assembly shown;

[0043] Figure 8 for Figure 3 A cross-sectional view of the end cap assembly shown;

[0044] Figure 9a for Figure 3The schematic diagram of the structure of the first pole, the first sealing ring, the end cover and the lower plastic before the end cover assembly is assembled;

[0045] Figure 9b for Figure 9a The schematic diagram of the structure of the first pole, the first sealing ring, the end cover and the lower plastic in the assembly process of the end cover assembly shown;

[0046] Fig.9c for Figure 9b The schematic diagram of the structure of the assembled first pole of the end cap assembly, the first sealing ring, the end cap and the lower plastic;

[0047] Fig.10 for Figure 2 An exploded schematic diagram of a second embodiment of an end cap assembly of an energy storage device shown;

[0048] Fig.11 for Fig.10 The end cap assembly is shown as an exploded schematic diagram at another angle;

[0049] Fig.12 for Fig.10 A cross-sectional view of a second embodiment of the first pole and the second pole of the end cap assembly shown;

[0050] Fig.13 for Fig.10 A cross-sectional view of the end cap assembly is shown.

[0051] Fig.14 for Fig.13 An exploded schematic diagram of a portion of the structure of the end cap assembly shown;

[0052] Fig.15a for Fig.14 The schematic diagram of the structure of the first pole with a first sealing ring and the second pole with a second sealing ring cooperating with the end cap and the lower plastic before the end cap assembly is assembled;

[0053] Fig.15b for Fig.15a The schematic diagram of the structure of the assembled end cap assembly showing the first pole with the first sealing ring and the second pole with the second sealing ring cooperating with the end cap and the lower plastic;

[0054] Fig.16 for Fig.10 A partial exploded schematic diagram of the end cap assembly is shown.

[0055] The nouns corresponding to the reference numerals in the figure are: energy storage device 1000, end cover assembly 100, housing 200, opening 201, end cover 10, first surface 11, second surface 12, first sealing groove 13, first groove bottom wall 131, first groove peripheral wall 132, second sealing groove 14, second groove bottom wall 141, second groove peripheral wall 142, first through hole 15, second through hole 16, limiting groove 17, lower plastic 20, top surface 21, bottom surface 22, first avoidance groove 23, third groove peripheral wall 231, third Groove bottom wall 232, second avoidance groove 24, fourth groove peripheral wall 241, fourth groove bottom wall 242, first pole through hole 25, second pole through hole 26, limiting column 27, first pole 30, first pole body 31, first mounting surface 311, first peripheral side surface 312, first protrusion 313, first welding surface 314, first flange 32, first connecting surface 321, first flange surface 322, first step 323, first step surface 324, first assembly surface 325, first folding portion 33, first Sealing surface 331, first appearance surface 332, first folded portion base 33a, first groove 35, second pole 40, second pole body 41, second mounting surface 411, second peripheral side surface 412, second protrusion 413, second welding surface 414, second flange 42, second connecting surface 421, second flange surface 422, second step 423, second step surface 424, second assembly surface 425, second folded portion 43, second sealing surface 431, second appearance surface 432, second folded portion base 43a, a second outer annular surface 441, a second inner annular surface 442, a second groove 45, a first sealing ring 50, a first sealing hole 50a, a first section 51, a second section 52, a third section 53, a second sealing ring 60, a second sealing hole 60a, a fourth section 61, a fifth section 62, a sixth section 63, a first gap H1, a second gap H2, an energy storage system 5000, a first electric energy conversion device 4100, a second electric energy conversion device 4200, a first electric equipment 3000, and a second electric equipment 2000. DETAILED DESCRIPTION

[0056] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0057] In this application, unless otherwise specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, they can be fixedly connected, detachably connected, or integrated; they can be mechanically connected, electrically connected, or able to communicate with each other; they can be directly connected, or indirectly connected through an intermediate medium, and they can be internally connected between two elements or the interaction relationship between two elements, unless otherwise specified and limited. And the terms "same", "equal" or "parallel" used in the following text are allowed to have a certain tolerance.

[0058] It should be noted that the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include at least one of the features.

[0059] Since the energy people need is highly temporal and spatial, in order to rationally utilize energy and improve energy utilization, it is necessary to use a medium or device to store one form of energy in the same form or convert it into another form of energy, and then release it in a specific form of energy based on future application needs. As we all know, to achieve the goal of carbon neutrality, the main way to generate green electricity is to develop green energy such as photovoltaics and wind power to replace fossil energy. At present, the generation of green electricity generally relies on photovoltaics, wind power, water potential, etc., while wind and solar energy generally have strong intermittent and volatile problems, which will cause instability in the power grid, insufficient electricity during peak hours, too much electricity during low hours, and unstable voltage will also cause damage to electricity. Therefore, it may cause "wind and light abandonment" problems due to insufficient electricity demand or insufficient grid acceptance capacity. To solve these problems, we must rely on energy storage. That is, electrical energy is converted into other forms of energy through physical or chemical means and stored, and then the energy is converted into electrical energy and released when needed. Simply put, energy storage is like a large "power bank". When photovoltaic and wind energy are sufficient, electrical energy is stored, and the stored electricity is released when needed.

[0060] Taking electrochemical energy storage as an example, the present application provides an energy storage device 1000, which has a group of chemical batteries inside. The energy storage device 1000 mainly uses the chemical elements in the chemical batteries as energy storage media. The charging and discharging process is accompanied by chemical reactions or changes in the energy storage media. Simply put, the electricity generated by wind energy and solar energy is stored in chemical batteries. When the use of external electricity reaches a peak, the stored electricity is released for use, or transferred to places where electricity is scarce for use.

[0061] At present, energy storage (i.e., energy storage) has a wide range of application scenarios, including (wind and solar) power generation side energy storage, grid side energy storage, base station side energy storage, and user side energy storage. The corresponding types of energy storage devices 1000 include:

[0062] (1) Large energy storage containers used in grid-side energy storage scenarios can serve as high-quality active and reactive power regulation power sources in the grid, achieve load matching of electric energy in time and space, enhance the ability to absorb renewable energy, and are of great significance in grid system backup, relieving peak load power supply pressure, and peak and frequency regulation;

[0063] (2) Small and medium-sized energy storage cabinets used in industrial and commercial energy storage scenarios (banks, shopping malls, etc.) on the user side mainly operate in the “peak shaving and valley filling” mode.

[0064] Since there is a large price difference in electricity charges at peak and valley locations according to electricity demand, after users have energy storage devices, in order to reduce costs, they usually charge the energy storage cabinets / boxes during the low electricity price period; during the peak electricity price period, the electricity in the energy storage device is discharged for use to achieve the purpose of saving electricity bills.

[0065] It should be noted that the above-mentioned energy storage containers, small and medium-sized energy storage cabinets, household small energy storage boxes and other equipment containing the energy storage device 1000 can be understood as electrical equipment.

[0066] See also Figure 1 , Figure 1 This is a diagram of an application scenario of the energy storage device provided in an embodiment of the present application.

[0067] The energy storage device 1000 provided in the embodiment of the present application is applied to an energy storage system 5000, which includes a first power conversion device 4100 (photovoltaic panel), a second power conversion device 4200 (wind turbine), a first power user 3000 (grid), a second power user 2000 (base station) and an energy storage device 1000. The energy storage system 5000 also includes an energy storage cabinet, and the energy storage device 1000 is installed in the energy storage cabinet, which can be installed outdoors. Specifically, the first power conversion device 4100 can convert solar energy into electrical energy during the period of low electricity prices, and the energy storage device 1000 is used to store the electrical energy and supply the first power user 3000 or the second power user 2000 during peak electricity consumption, or to supply power when the first power user 3000 or the second power user 2000 is powered off / out of power. The second power conversion device 4200 can convert wind energy into electric energy, and the energy storage device 1000 is used to store the electric energy and supply it to the first power device 3000 or the second power device 2000 during peak power consumption, or to supply power when the first power device 3000 or the second power device 2000 is powered off / out of power. The transmission of electric energy can be carried out using a high-voltage cable.

[0068] It should be noted that the first power-consuming device 3000, the second power-consuming device 2000 and other devices including the energy storage device 1000 can be understood as power-consuming devices. The energy storage device 1000 supplies power to the power-consuming devices.

[0069] There may be multiple energy storage devices 1000, and multiple energy storage devices 1000 are connected in series or in parallel. In this embodiment, "multiple" means two or more.

[0070] 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. The actual application form of the energy storage device 1000 provided in the embodiment of the present application may be but is not limited to the listed products, and may also be other application forms. For example, the energy storage device 1000 may be a secondary battery such as a nickel-metal hydride battery, a nickel-cadmium battery, a lead-acid (or lead storage) battery, a lithium-ion battery, a polymer lithium-ion battery, etc. When the energy storage device 1000 is a single cell, it may be a cylindrical battery, a square battery, or a battery of other shapes. In this embodiment, the energy storage device 1000 is described using a square battery as an example. Among them, the square battery is a secondary battery.

[0071] See also Figure 2 , Figure 2 for Figure 1 Schematic diagram of the structure of the energy storage device shown.

[0072] For ease of description, the width direction of the energy storage device 1000 is defined as the X-axis direction, the length direction is defined as the Y-axis direction, and the height direction is defined as the Z-axis direction. The X-axis direction, the Y-axis direction, and the Z-axis direction are mutually perpendicular.

[0073] The directional terms such as "upper", "top", "lower", and "bottom" mentioned in the description of the embodiments of the present application are based on the Figure 2 The description of the directions shown does not constitute a limitation on the actual application scenarios of the energy storage device 1000. Specifically, the positive direction toward the Z axis is the top or upper side of the energy storage device 1000, and the negative direction toward the Z axis is the bottom or lower side of the energy storage device 1000.

[0074] In this embodiment, the energy storage device 1000 includes an end cap assembly 100, a housing 200, and an electrode assembly (not shown). The housing 200 has an opening 201 and is provided with a receiving cavity (not shown). The receiving cavity is communicated with the opening 201. The electrode assembly is accommodated in the receiving cavity of the housing 200. The end cap assembly 100 is mounted on one end of the electrode assembly and is sealed to the opening 201 of the housing 200 to isolate the internal environment of the energy storage device 1000 from the external environment. In this embodiment, the housing 200 is a rectangular shell.

[0075] See also Figure 3, Figure 4 and Figure 5 , Figure 3 for Figure 2 The schematic diagram of the structure of the first embodiment of the end cover assembly of the energy storage device shown in FIG. Figure 4 for Figure 3 An exploded schematic diagram of the end cap assembly is shown. Figure 5 for Figure 4 A schematic exploded view of the end cap assembly from another angle is shown.

[0076] The end cap assembly 100 includes an end cap 10, a lower plastic 20, a first pole 30, a second pole 40, a first sealing ring 50 and a second sealing ring 60. The end cap 10 and the lower plastic 20 are stacked in the Z-axis direction. The first pole 30 and the second pole 40 are respectively located at opposite ends of the length direction (i.e., the Y-axis direction) of the end cap assembly 100. The first pole 30 is inserted through the end cap 10 and the lower plastic 20. The first sealing ring 50 is located between the first pole 30 and the end cap 10, and is connected to the lower plastic 20 to seal the assembly gap between the first pole 30 and the end cap 10 and the assembly gap between the first pole 30 and the lower plastic 20. The first sealing ring 50 is used to insulate the first pole 30 and the end cap 10. The second pole 40 is inserted through the end cap 10 and the lower plastic 20. The second sealing ring 60 is located between the second pole 40 and the end cover 10 and is connected to the lower plastic 20 to seal the assembly gap between the second pole 40 and the end cover 10 and the assembly gap between the second pole 40 and the lower plastic 20. The second sealing ring 60 is used to insulate the second pole 40 and the end cover 10.

[0077] In this embodiment, the first pole 30 may be a negative pole, and the second pole 40 may be a positive pole. In other embodiments, the first pole 30 may be a positive pole, and the second pole 40 may be a negative pole. This application does not limit this.

[0078] like Figure 4 and Figure 5 As shown, in this embodiment, the end cover 10 is substantially a rectangular plate. The end cover 10 includes a first surface 11 and a second surface 12. The first surface 11 and the second surface 12 are arranged opposite to each other along the thickness direction of the end cover 10 (ie, the Z-axis direction).

[0079] The end cover 10 further includes a first sealing groove 13 and a second sealing groove 14. The first sealing groove 13 and the second sealing groove 14 are both recessed on the second surface 12 of the end cover 10 and recessed toward the first surface 11. The first sealing groove 13 and the second sealing groove 14 are spaced apart along the length direction (i.e., the Y-axis direction) of the end cover 10.

[0080] The first sealing groove 13 is used to cooperate with the first sealing ring 50 and to accommodate part of the first sealing ring 50. The first sealing groove 13 includes a first groove bottom wall 131 and a first groove peripheral wall 132. The first groove peripheral wall 132 surrounds the periphery of the first groove bottom wall 131 and is connected to the first groove bottom wall 131. The first groove peripheral wall 132 is connected to the second surface 12 of the end cover 10. The orientation of the first groove bottom wall 131 is consistent with the orientation of the second surface 12. The first sealing groove 13 can be, but is not limited to, a hexagonal groove, a rectangular groove, a circular groove, etc. Exemplarily, the first sealing groove 13 is a hexagonal groove.

[0081] The second sealing groove 14 is used to cooperate with the second sealing ring 60 and to accommodate part of the second sealing ring 60. The second sealing groove 14 includes a second groove bottom wall 141 and a second groove peripheral wall 142. The second groove peripheral wall 142 surrounds the periphery of the second groove bottom wall 141 and is connected to the second groove bottom wall 141. The second groove peripheral wall 142 is connected to the second surface 12 of the end cover 10. The orientation of the second groove bottom wall 141 is consistent with the orientation of the second surface 12. The second sealing groove 14 can be, but is not limited to, a hexagonal groove, a rectangular groove, a circular groove, etc. Exemplarily, the second sealing grooves 14 are all hexagonal grooves.

[0082] The end cover 10 further includes a first through hole 15 and a second through hole 16. The first through hole 15 penetrates the first groove bottom wall 131 of the first sealing groove 13 and the first surface 11 of the end cover 10. The first through hole 15 is used for the first pole 30 to pass through. The second through hole 16 penetrates the second groove bottom wall 141 of the second sealing groove 14 and the first surface 11 of the end cover 10. The second through hole 16 is used for the second pole 40 to pass through. The first through hole 15 and the second through hole 16 may be, but are not limited to, a circular hole, a hexagonal hole, a rectangular hole, etc. Exemplarily, the first through hole 15 and the second through hole 16 are both hexagonal holes.

[0083] In this embodiment, the lower plastic 20 is substantially a rectangular plate. The lower plastic 20 includes a top surface 21 and a bottom surface 22. The top surface 21 and the bottom surface 22 are disposed opposite to each other along the thickness direction of the lower plastic 20 (ie, the Z-axis direction).

[0084] The lower plastic 20 further includes a first avoidance groove 23 and a second avoidance groove 24. The first avoidance groove 23 and the second avoidance groove 24 are both recessed on the top surface 21 of the lower plastic 20 and recessed toward the bottom surface 22. The first avoidance groove 23 and the second avoidance groove 24 are spaced apart along the length direction (i.e., the Y-axis direction) of the lower plastic 20.

[0085] The first avoidance groove 23 is used to cooperate with the first sealing ring 50 and to accommodate part of the first sealing ring 50. The first avoidance groove 23 includes a third groove peripheral wall 231 and a third groove bottom wall 232. The third groove peripheral wall 231 surrounds the periphery of the third groove bottom wall 232 and is connected to the third groove bottom wall 232 and the top surface 21 of the lower plastic 20. The orientation of the third groove bottom wall 232 is consistent with the orientation of the top surface 21. The first avoidance groove 23 can be, but is not limited to, a hexagonal groove, a rectangular groove, a circular groove, etc. Exemplarily, the first avoidance grooves 23 are all hexagonal grooves.

[0086] The second avoidance groove 24 is used to cooperate with the second sealing ring 60 and to accommodate part of the second sealing ring 60. The second avoidance groove 24 includes a fourth groove peripheral wall 241 and a fourth groove bottom wall 242. The fourth groove peripheral wall 241 surrounds the periphery of the fourth groove bottom wall 242 and is connected to the fourth groove bottom wall 242 and the top surface 21 of the lower plastic 20. The orientation of the fourth groove bottom wall 242 is consistent with the orientation of the top surface 21. The second avoidance groove 24 can be, but is not limited to, a hexagonal groove, a rectangular groove, a circular groove, etc. Exemplarily, the second avoidance grooves 24 are all hexagonal grooves.

[0087] The lower plastic 20 also includes a first pole through hole 25 and a second pole through hole 26. The first pole through hole 25 penetrates the third slot bottom wall 232 of the first avoidance slot 23 and the bottom surface 22 of the lower plastic 20. The first pole through hole 25 is used for the first pole 30 to pass through. The first pole through hole 25 penetrates the fourth slot bottom wall 242 of the second avoidance slot 24 and the bottom surface 22 of the lower plastic 20. The second pole through hole 26 is used for the second pole 40 to pass through. The first pole through hole 25 and the second pole through hole 26 can be, but are not limited to, a circular hole, a hexagonal hole, a rectangular hole, etc. Exemplarily, the first pole through hole 25 and the second pole through hole 26 are both hexagonal holes.

[0088] Please also read Figure 4 , Figure 5 and Figure 6 , Figure 6 for Figure 4 A cross-sectional view of a first sealing ring and a second sealing ring of an end cap assembly is shown.

[0089] In this embodiment, the first sealing ring 50 is a polygonal ring structure. A first sealing hole 50a is provided in the middle of the first sealing ring 50. The first sealing hole 50a is used for the first pole 30 to pass through. The first sealing ring 50 is made of a rubber synthetic material that is resistant to low temperatures and electrolytes, such as EPDM (Ethylene Propylene Diene Monomer), and has deformation capability.

[0090] The first sealing ring 50 includes a first section 51, a second section 52 and a third section 53. The second section 52 is connected to the first section 51 and the third section 53. Along the Z-axis direction, the first section 51 and the third section 53 are spaced and opposite to each other. The second section 52 extends along the axial direction of the first sealing ring 50. The extension direction of the second section 52 is at an angle to the extension direction of the first section 51, and the extension direction of the second section 52 is at an angle to the extension direction of the third section 53. Exemplarily, the first section 51 and the third section 53 are both straight sections. That is, the first section 51 and the third section 53 are both parallel to the surface extension direction of the end cover 10. The extension direction of the first section 51 and the extension direction of the third section 53 are both perpendicular to the extension direction of the second section 52. Along the axial direction perpendicular to the first sealing ring 50, the first section 51 and the third section 53 both extend away from the axis of the first sealing ring 50.

[0091] It should be noted that the radial width of the first section 51 is greater than the width of the third section 53. The first section 51, the second section 52 and the third section 53 together form a first sealing hole 50a. Figure 6 The dashed lines are used to clearly distinguish the first section 51 , the second section 52 and the third section 53 .

[0092] In this embodiment, the structure and material of the second sealing ring 60 are the same as those of the first sealing ring 50. The second sealing ring 60 is a polygonal ring structure. A second sealing hole 60a is provided in the middle of the second sealing ring 60. The second sealing hole 60a is used for the second pole 40 to pass through. The second sealing ring 60 is made of a rubber synthetic material such as EPDM that is resistant to low temperatures and electrolytes, and has deformation capability.

[0093] The second sealing ring 60 includes a fourth section 61, a fifth section 62 and a sixth section 63. The fifth section 62 is connected to the fourth section 61 and the sixth section 63. Along the Z-axis direction, the fourth section 61 and the sixth section 63 are spaced and opposite to each other. The extension direction of the fifth section 62 extends along the axial direction of the second sealing ring 60. The extension direction of the fifth section 62 is at an angle to the extension direction of the fourth section 61, and the extension direction of the fifth section 62 is at an angle to the extension direction of the sixth section 63. Exemplarily, the fourth section 61 and the sixth section 63 are both straight sections. That is, the fourth section 61 and the sixth section 63 are both parallel to the surface extension direction of the end cover 10. The extension direction of the fourth section 61 and the extension direction of the sixth section 63 are both perpendicular to the extension direction of the fifth section 62. Along the axial direction perpendicular to the second sealing ring 60, the fourth section 61 and the sixth section 63 both extend away from the axis of the second sealing ring 60.

[0094] It should be noted that the radial width of the sixth section 63 is greater than the width of the fourth section 61. The fourth section 61, the fifth section 62 and the sixth section 63 together form a second sealing hole 60a. Figure 6 The dashed lines are used to clearly distinguish the fourth segment 61 , the fifth segment 62 and the sixth segment 63 .

[0095] In some embodiments, the structure of the second sealing ring 60 may be different from that of the first sealing ring 50. Alternatively, the material of the second sealing ring 60 may be different from that of the first sealing ring 50. This application does not limit this.

[0096] Please also read Figure 4 , Figure 5 and Figure 7 , Figure 7 for Figure 4 A cross-sectional view of a first embodiment of a first pole and a second pole of an end cap assembly is shown.

[0097] In this embodiment, the first pole 30 is a column with an I-shaped cross section. The first pole 30 includes a first pole body 31 and a first flange 32. Along the height direction of the first pole 30 (i.e., the Z-axis direction), the first flange 32 is connected to one end of the first pole body 31. Exemplarily, the first flange 32 is connected to the bottom end surface of the first pole body 31.

[0098] The first flange 32 includes a first connection surface 321 and a first flange surface 322. The first connection surface 321 and the first flange surface 322 are disposed opposite to each other along the thickness direction of the first flange 32. The first connection surface 321 surrounds the first pole body 31. The first flange surface 322 faces away from the first pole body 31.

[0099] The first flange 32 further includes a first step 323. The first step 323 is located on the outer peripheral surface of the first flange 32, and the first step 323 is recessed in the first connection surface 321 and recessed in the direction of the second connection surface 421. It can be understood that the first step 323 is formed by cutting the periphery of the end of the first flange 32 close to the first pole body 31. Exemplarily, the cross section of the first flange 32 can be roughly an inverted "T"-shaped column.

[0100] The first step 323 includes a first step surface 324 and a first assembly surface 325. The first step surface 324 is connected to the first assembly surface 325 and the first connection surface 321 of the first flange 32, and the first step surface 324 is respectively arranged at an angle with the first connection surface 321 and the first assembly surface 325. The orientation of the first assembly surface 325 is the same as that of the first connection surface 321.

[0101] The first pole body 31 is connected to the first connection surface 321 of the first flange 32. The first pole body 31 is coaxially arranged with the first flange 32. The first pole body 31 includes a first mounting surface 311 and a first peripheral side surface 312. The first peripheral side surface 312 is arranged around the periphery of the first mounting surface 311, and the first peripheral side surface 312 is connected to the first mounting surface 311 and the first connection surface 321. The first mounting surface 311 faces away from the first flange 32.

[0102] In this embodiment, a first protrusion 313 is convexly provided at the middle position of the first mounting surface 311 of the first pole body 31. It can be understood that the first pole body 31 also includes a first protrusion 313, which is convexly provided on the first mounting surface 311 and is located at the middle position of the first mounting surface 311. The first protrusion 313 includes a first welding surface 314. The first welding surface 314 faces away from the first mounting surface 311, and the orientation of the first welding surface 314 is the same as the orientation of the first mounting surface 311. The first protrusion 313 can be welded to a conductor (such as a connecting piece, etc.) outside the energy storage device 1000 through the first welding surface 314 to achieve electrical connection between the first pole 30 and the conductor (such as a connecting piece, etc.) outside the energy storage device 1000. The first protrusion 313 can be, but is not limited to, a circular protrusion, a hexagonal protrusion, a rectangular protrusion, etc. Exemplarily, the first pole body 31 is roughly a column. The first protrusion 313 is a hexagonal protrusion.

[0103] The first pole 30 also includes a first folded portion 33. The first folded portion 33 is protruding from the periphery of the end of the first pole body 31 away from the first flange 32, and surrounds the first mounting surface 311. The width direction of the first folded portion 33 is set at an angle with the axial direction of the first pole body 31. Along the height direction of the first pole 30, the first folded portion 33 is opposite to the first flange 32 and is spaced apart. The first folded portion 33 is used to cooperate with the first flange 32 to crimp the first sealing ring 50. The first folded portion 33 is formed by flanging. Exemplarily, the width direction of the first folded portion 33 is set at a 90-degree angle with the axial direction of the first pole body 31.

[0104] The first folded portion 33 includes a first sealing surface 331 and a first appearance surface 332. The first sealing surface 331 and the first appearance surface 332 are arranged opposite to each other along the thickness direction of the first folded portion 33. The first sealing surface 331 is connected to the first peripheral side surface 312 of the first pole body 31, and is arranged at an angle with the first peripheral side surface 312, and the first sealing surface 331 and the first connecting surface 321 of the first flange 32 are opposite and spaced along the Z-axis direction. The first appearance surface 332 is connected to the first mounting surface 311 of the first pole body 31. The first appearance surface 332 can be flush with the first mounting surface 311, or, along the direction from the first folded portion 33 to the first flange 32, the first mounting surface 311 protrudes from the first appearance surface 332. Exemplarily, the first appearance surface 332 is flush with the first mounting surface 311, and the first sealing surface 331 is arranged at a 90-degree angle with the first peripheral side surface 312.

[0105] It should be noted that the first folded portion 33 may be integrally formed with the first pole body 31 , or may be separately formed from the first pole body 31 and connected by welding, bonding, or the like.

[0106] In this embodiment, the structure of the second pole 40 is the same as that of the first pole 30. The second pole 40 is a column with an I-shaped cross section. Along the height direction of the second pole 40 (i.e., the Z-axis direction), the second flange 42 is connected to one end of the second pole body 41. For example, the first flange 32 is connected to the bottom end surface of the first pole body 31.

[0107] The second flange 42 includes a second connection surface 421 and a second flange surface 422. The second connection surface 421 and the second flange surface 422 are disposed opposite to each other along the thickness direction of the second flange 42. The second connection surface 421 surrounds the second pole body 41. The second flange surface 422 faces away from the second pole body 41.

[0108] The second flange 42 further includes a second step 423. The second step 423 is located on the outer peripheral surface of the second flange 42, and the second step 423 is recessed in the second connection surface 421 and recessed in the direction of the second flange surface 422. It can be understood that the second step 423 is formed by cutting the periphery of the end of the second flange 42 close to the second pole body 41. Exemplarily, the cross section of the second flange 42 can be roughly an inverted "T"-shaped column.

[0109] The second step 423 includes a second step surface 424 and a second assembly surface 425. The second step surface 424 is connected to the second assembly surface 425 and the second connection surface 421 of the second flange 42, and the second step surface 424 is respectively arranged at an angle with the second connection surface 421 and the second assembly surface 425. The direction of the second assembly surface 425 is the same as that of the second connection surface 421.

[0110] The second pole body 41 is connected to the second connection surface 421 of the second flange 42. The second pole body 41 is coaxially arranged with the second flange 42. The second pole body 41 includes a second mounting surface 411 and a second peripheral side surface 412. The second peripheral side surface 412 is arranged around the periphery of the second mounting surface 411, and the second peripheral side surface 412 is connected to the second mounting surface 411 and the second connection surface 421. The second mounting surface 411 faces away from the second flange 42.

[0111] In this embodiment, a second protrusion 413 is convexly provided at the middle position of the second mounting surface 411 of the second pole body 41. It can be understood that the second pole body 41 also includes a second protrusion 413, which is convexly provided on the second mounting surface 411 and is located at the middle position of the second mounting surface 411. The second protrusion 413 includes a second welding surface 414. The second welding surface 414 faces away from the second mounting surface 411, and the direction of the second welding surface 414 is the same as the direction of the second mounting surface 411. The second protrusion 413 can be welded to the conductor (such as a connecting piece, etc.) outside the energy storage device 1000 through the second welding surface 414 to achieve electrical connection between the second pole 40 and the conductor (such as a connecting piece, etc.) outside the energy storage device 1000. The second protrusion 413 can be, but is not limited to, a circular protrusion, a hexagonal protrusion, a rectangular protrusion, etc. Exemplarily, the second pole body 41 is roughly a column. The second protrusion 413 is a hexagonal protrusion.

[0112] The second pole 40 also includes a second folded portion 43. The second folded portion 43 is protruding from the periphery of the end of the second pole body 41 away from the second flange 42 and surrounds the second mounting surface 411. The width direction of the second folded portion 43 is set at an angle with the axial direction of the second pole body 41. Along the height direction of the second pole 40, the second folded portion 43 is opposite to the second flange 42 and is spaced apart. The second folded portion 43 is used to cooperate with the second flange 42 to crimp the second sealing ring 60. The second folded portion 43 is formed by flanging. Exemplarily, the width direction of the second folded portion 43 is set at a 90-degree angle with the axial direction of the second pole body 41.

[0113] The second folded portion 43 includes a second sealing surface 431 and a second appearance surface 432. The second sealing surface 431 and the second appearance surface 432 are arranged opposite to each other along the thickness direction of the second folded portion 43. The second sealing surface 431 is connected to the second peripheral side surface 412 of the second pole body 41, and is arranged at an angle with the second peripheral side surface 412, and the second sealing surface 431 and the second connecting surface 421 of the second flange 42 are opposite and spaced along the Z-axis direction. The second appearance surface 432 is connected to the second mounting surface 411 of the second pole body 41. The second appearance surface 432 can be flush with the second mounting surface 411, or, along the direction from the second folded portion 43 to the second flange 42, the second mounting surface 411 protrudes from the second appearance surface 432. Exemplarily, the second appearance surface 432 is flush with the second mounting surface 411, and the second sealing surface 431 is arranged at a 90-degree angle with the second peripheral side surface 412.

[0114] It should be noted that the second folded portion 43 may be integrally formed with the second pole body 41 , or may be separately formed from the second pole body 41 and connected by welding, bonding, or the like.

[0115] In some embodiments, the structure of the second pole 40 may be different from the structure of the first pole 30. This application does not limit this.

[0116] See also Figure 8 , Figure 8 for Figure 3 A cross-sectional view of the end cap assembly is shown.

[0117] The lower plastic 20 and the end cover 10 are stacked along the Z-axis direction. Specifically, the top surface 21 of the lower plastic 20 is connected to the second surface 12 of the end cover 10. The notch of the first avoidance groove 23 of the lower plastic 20 is opposite to and connected to the notch of the first sealing groove 13 of the end cover 10. The third groove bottom wall 232 of the first avoidance groove 23 is opposite to the first groove bottom wall 131 of the first sealing groove 13, and forms a first gap H1. The first gap H1 is connected to the first through hole 15 and the first pole through hole 25. The first gap H1 is used to accommodate part of the third section 53 of the first sealing ring 50. The first pole through hole 25 of the lower plastic 20 is connected to the first through hole 15 of the end cover 10 and is coaxially arranged. The notch of the second avoidance groove 24 of the lower plastic 20 is opposite to and connected to the notch of the second sealing groove 14 of the end cover 10. The fourth groove bottom wall 242 of the second avoidance groove 24 is opposite to the second groove bottom wall 141 of the second sealing groove 14, and forms a second gap H2. The second gap H2 is connected to the second pole through hole 26 and the second through hole 16. The second gap H2 is used to accommodate part of the sixth section 63 of the second sealing ring 60. The second pole through hole 26 of the lower plastic 20 is connected to the second through hole 16 of the end cover 10 and is coaxially arranged.

[0118] The first pole 30, the second pole 40, the first sealing ring 50 and the second sealing ring 60 are installed together on the lower plastic 20 and the end cover 10 to form the end cover assembly 100. The first pole 30 is inserted through the first sealing hole 50a of the first sealing ring 50, and is inserted through the first pole through hole 25 of the lower plastic 20 and the first through hole 15 of the end cover 10 together with the first sealing ring 50. The first sealing ring 50 is interference fit with the end cover 10, the lower plastic 20 and the first pole 30.

[0119] The first sealing ring 50 is sleeved on the outer circumference of the first pole body 31, and then installed together with the first pole 30 on the end cover 10 and the lower plastic 20. The first flange 32 of the first pole 30, the lower plastic 20, the end cover 10 and the first folded portion 33 together clamp the first sealing ring 50, and the end cover 10, the lower plastic 20 and the first pole 30 compress the first sealing ring 50. The part of the first sealing ring 50 clamped between the lower plastic 20 and the end cover 10 extends into the first gap H1. The following further describes the matching relationship after assembly, and the specific assembly sequence is described later. The first sealing ring 50 is located between the first flange 32 and the first folded portion 33. The part of the end cover 10 around the first through hole 15 is located between the first section 51 and the third section 53 of the first sealing ring 50. The end cover 10 and the first section 51 and the third section 53 are clamped by the first folded portion 33 and the first flange 32.

[0120] Specifically, the first section 51 of the first sealing ring 50 is connected to the first sealing surface 331 of the first folded portion 33 and the first surface 11 of the end cover 10. The first section 51 is interference fit with the end cover 10 and the first folded portion 33, which not only seals the assembly gap between the first folded portion 33 and the end cover 10, effectively preventing the electrolyte splashed from the outside of the energy storage device 1000 from penetrating into the first pole 30 from the assembly gap, thereby improving the reliability of the end cover assembly 100, but also insulates the first folded portion 33 from the end cover 10. When the first pole 30 and the first sealing ring 50 are assembled to the end cover 10, the first folded portion 33 and the end cover 10 squeeze the first section 51, so that the first section 51 is deformed and extends to both ends of its width direction (i.e., one end connected to the second section 52 and one end away from the second section 52). The outer circumference of the first section 51 is convex compared to the outer circumference of the first folded portion 33, so as to increase the creepage distance from the end cover 10 to the first pole 30, thereby ensuring the safety and reliability of the end cover assembly 100. Since the first section 51 is interference-fitted with the first folded portion 33 and the end cover 10, the first section 51 has a first compression amount. The first compression amount is the difference between the thickness of the first section 51 before compression and the thickness after compression.

[0121] The second section 52 of the first sealing ring 50 is connected to the first circumferential side surface 312 of the first pole body 31 and the hole wall of the first through hole 15 of the end cover 10, and is interference fit with the end cover 10 and the first pole body 31, which not only seals the assembly gap between the first pole body 31 and the end cover 10, effectively preventing the electrolyte from penetrating into the interior of the first pole 30 from the assembly gap, improving the reliability of the end cover assembly 100, but also insulates the first pole body 31 from the end cover 10. When the first pole 30 and the first sealing ring 50 are assembled to the end cover 10, the first pole body 31 and the end cover 10 squeeze the second section 52, so that the second section 52 is deformed and extends in the direction of the first section 51 and the third section 53. Since the second section 52 is interference fit with the first pole body 31 and the end cover 10, the second section 52 has a certain amount of compression. In some embodiments, the second section 52 may not have an interference fit with the first pole body 31 and the end cover 10 , that is, the first pole body 31 and the end cover 10 do not squeeze the second section 52 , and thus the second section 52 may not be compressed.

[0122] The third section 53 of the first sealing ring 50 is connected to the first connection surface 321 of the first flange 32 and the first groove bottom wall 131 of the first sealing groove 13 of the end cover 10, and is interference fit with the end cover 10 and the first flange 32, which not only seals the assembly gap between the first flange 32 and the end cover 10, effectively prevents the electrolyte from penetrating into the first pole 30 from the assembly gap, improves the reliability of the end cover assembly 100, but also insulates the first flange 32 from the end cover 10. In addition, when the first pole 30 and the first sealing ring 50 are assembled to the end cover 10, the first flange 32 and the end cover 10 squeeze the third section 53, so that the third section 53 is deformed and extends to both ends of its width direction (i.e., one end connected to the second section 52 and one end away from the second section 52), and the third section 53 squeezes into the first gap H1 between the first sealing groove 13 and the first avoidance groove 23 of the lower plastic 20, and connects the first groove bottom wall 131 of the first sealing groove 13 and the third groove bottom wall 232 of the first avoidance groove 23. It can be understood that the outer circumference of the third section 53 is protruding compared to the outer circumference of the first flange 32, and the third section 53 can cover the assembly gap between the lower plastic 20 and the first pole 30, prevent the metal powder from being present in the assembly gap and causing the end cover 10 and the first pole 30 to short-circuit, thereby improving the voltage resistance of the end cover assembly 100. Since the third section 53 is interference-fitted with the first flange 32, the lower plastic 20 and the end cover 10, the third section 53 has a second compression amount. The second compression amount is the difference between the thickness of the third section 53 before compression and the thickness after compression.

[0123] Since the radial width of the first section 51 is smaller than the radial width of the third section 53, the contact area between the first section 51 and the first surface 11 of the end cover 10 is smaller than the contact area between the third section 53 and the second surface 12 of the end cover 10. That is, the projection of the first section 51 in the thickness direction of the end cover assembly 100 is located within the projection of the third section 53 in the thickness direction of the end cover assembly 100, so as to ensure the fixation of the first sealing ring 50 after the flanging operation of the first pole 30, and improve the stability of the compression amount of the first sealing ring 50.

[0124] The first step 323 of the first flange 32 cooperates with the lower plastic 20. The first step surface 324 of the first step 323 is opposite to and spaced from the hole wall of the first pole through hole 25 of the lower plastic 20. The first assembly surface 325 abuts against the bottom surface 22 of the lower plastic 20. The first step 323 not only realizes the limit between the first pole 30 and the lower plastic 20, but also abuts the lower plastic 20 against the end cover 10 to prevent the lower plastic 20 from being separated from the end cover 10 due to gravity. In some embodiments, the third section 53 of the first sealing ring 50 can also be squeezed into the assembly gap between the first step surface 324 and the hole wall of the first pole through hole 25 to seal the first pole 30 and the lower plastic 20, further increase the sealing performance of the end cover assembly 100, and improve the reliability of the end cover assembly 100.

[0125] It should be noted that, through the tool efficient detection, the sum of the first compression amount of the first section 51 and the second compression amount of the third section 53 of the assembled first sealing ring 50 is 5% to 55% (including the end values ​​of 5% and 55%) of the sum of the thicknesses of the first section 51 and the third section 53 before compression. Since both the first section 51 and the third section 53 have a certain compression amount, even when the first sealing ring 50 is subjected to high temperature, the first section 51 and the third section 53 can prevent the first pole 30 from sinking due to gravity.

[0126] The second pole 40 is inserted into the second sealing hole 60a of the second sealing ring 60, and is inserted into the second pole through hole 26 of the lower plastic 20 and the second through hole 16 of the end cover 10 together with the second sealing ring 60. The second sealing ring 60 is interference fit with the end cover 10, the lower plastic 20 and the second pole 40.

[0127] The second sealing ring 60 is sleeved on the outer circumference of the second pole body 41, and then installed together with the second pole 40 on the end cover 10 and the lower plastic 20. The second flange 42 of the second pole 40, the lower plastic 20, the end cover 10 and the second folding portion 43 jointly clamp the second sealing ring 60, and the end cover 10, the lower plastic 20 and the second pole 40 compress the second sealing ring 60. The part of the second sealing ring 60 clamped between the lower plastic 20 and the end cover 10 extends into the second gap H2. The following further describes the matching relationship after assembly, and the specific assembly sequence is described later. The second sealing ring 60 is located between the second flange 42 and the second folding portion 43. The part of the end cover 10 around the second through hole 16 is located between the fourth section 61 and the sixth section 63 of the second sealing ring 60. The end cover 10 and the fourth section 61 and the sixth section 63 are clamped by the second folding portion 43 and the second flange 42.

[0128] Specifically, the fourth section 61 of the second sealing ring 60 is connected to the second sealing surface 431 of the second folded portion 43 and the second surface 12 of the end cover 10. The fourth section 61 is interference fit with the end cover 10 and the second folded portion 43, which not only seals the assembly gap between the second folded portion 43 and the end cover 10, effectively preventing the electrolyte splashed from the outside of the energy storage device 1000 from penetrating into the second pole 40 from the assembly gap, thereby improving the reliability of the end cover assembly 100, but also insulates the second folded portion 43 from the end cover 10. When the second pole 40 and the second sealing ring 60 are assembled to the end cover 10, the second folded portion 43 and the end cover 10 squeeze the fourth section 61, so that the fourth section 61 is deformed and extends to both ends of its width direction (i.e., one end connected to the second section 52 and one end away from the second section 52). The outer circumference of the fourth section 61 is convex compared to the outer circumference of the second folded portion 43, so as to increase the creepage distance from the end cover 10 to the second pole 40, thereby ensuring the safety of the end cover assembly 100. Since the fourth section 61 is interference fit with the second folded portion 43 and the end cover 10, the fourth section 61 has a third compression amount. The third compression amount is the difference between the thickness of the fourth section 61 before compression and the thickness after compression.

[0129] The fifth section 62 of the second sealing ring 60 is connected to the second circumferential side surface 412 of the second pole body 41 and the hole wall of the second through hole 16 of the end cover 10, and is interference fit with the end cover 10 and the second pole body 41, which not only seals the assembly gap between the second pole body 41 and the end cover 10, effectively preventing the electrolyte from penetrating into the interior of the second pole 40 from the assembly gap, improving the reliability of the end cover assembly 100, but also insulates the second pole body 41 from the end cover 10. When the second pole 40 and the second sealing ring 60 are assembled to the end cover 10, the second pole body 41 and the end cover 10 squeeze the fifth section 62, so that the fifth section 62 is deformed and extends in the direction of the fourth section 61 and the sixth section 63. Since the fifth section 62 is interference fit with the second pole body 41 and the end cover 10, the fifth section 62 has a certain amount of compression. In some embodiments, the fifth section 62 may not have an interference fit with the second pole body 41 and the end cover 10 , that is, the second pole body 41 and the end cover 10 do not squeeze the fifth section 62 , and thus the fifth section 62 may not be compressed.

[0130] The sixth section 63 of the second sealing ring 60 is connected to the second connection surface 421 of the second flange 42 and the second groove bottom wall 141 of the second sealing groove 14 of the end cover 10, and is interference fit with the end cover 10 and the second flange 42, which not only seals the assembly gap between the second flange 42 and the end cover 10, effectively prevents the electrolyte from penetrating into the interior of the second pole 40 from the assembly gap, improves the reliability of the end cover assembly 100, but also insulates the second flange 42 from the end cover 10. In addition, when the second pole 40 and the second sealing ring 60 are assembled to the end cover 10, the second flange 42 and the end cover 10 squeeze the sixth section 63, so that the sixth section 63 is deformed and extends to both ends of its width direction (i.e., one end connected to the fifth section 62 and one end away from the fifth section 62), and the sixth section 63 squeezes into the second gap H2 between the second sealing groove 14 and the second avoidance groove 24 of the lower plastic 20, and connects the second groove bottom wall 141 of the second sealing groove 14 and the fourth groove bottom wall 242 of the second avoidance groove 24. It can be understood that the outer circumference of the sixth section 63 is protruding compared to the outer circumference of the second flange 42, and the sixth section 63 can cover the assembly gap between the lower plastic 20 and the second pole 40, prevent the metal powder from being present in the assembly gap and causing the end cover 10 and the second pole 40 to short-circuit, thereby improving the voltage resistance of the end cover assembly 100. Since the sixth section 63 is interference-fitted with the second flange 42, the lower plastic 20 and the end cover 10, the sixth section 63 has a fourth compression amount. The fourth compression amount is the difference between the thickness of the sixth section 63 before compression and the thickness after compression.

[0131] Since the radial width of the fourth section 61 is smaller than the radial width of the sixth section 63, the contact area between the fourth section 61 and the first surface 11 of the end cover 10 is smaller than the contact area between the sixth section 63 and the second surface 12 of the end cover 10. That is, the projection of the fourth section 61 in the thickness direction of the end cover assembly 100 is located within the projection of the sixth section 63 in the thickness direction of the end cover assembly 100, so as to ensure the fixation of the second sealing ring 60 after the flanging operation of the second pole 40, and improve the stability of the compression amount of the second sealing ring 60.

[0132] The second step 423 of the second flange 42 cooperates with the lower plastic 20. The second step surface 424 of the second step 423 is opposite to and spaced from the hole wall of the second pole through hole 26 of the lower plastic 20. The second assembly surface 425 abuts against the bottom surface 22 of the lower plastic 20. The second step 423 not only realizes the limit between the second pole 40 and the lower plastic 20, but also abuts the lower plastic 20 against the end cover 10 to prevent the lower plastic 20 from being separated from the end cover 10 due to gravity. In some embodiments, the sixth section 63 of the second sealing ring 60 can also be squeezed into the assembly gap between the second step surface 424 and the hole wall of the second pole through hole 26 to seal the second pole 40 and the lower plastic 20, further increasing the sealing performance and reliability of the end cover assembly 100.

[0133] It should be noted that, through the tool efficient detection, the sum of the third compression amount of the fourth section 61 and the fourth compression amount of the sixth section 63 of the assembled second sealing ring 60 is 5% to 55% (including the end values ​​of 5% and 55%) of the sum of the thickness of the fourth section 61 and the sixth section 63 before compression. Since the fourth section 61 and the sixth section 63 both have a certain amount of compression, even when the second sealing ring 60 is subjected to high temperature, the fourth section 61 and the sixth section 63 can prevent the second pole 40 from sinking due to gravity.

[0134] See also Figure 9a , Figure 9b and Fig.9c , Figure 9a for Figure 3 The schematic diagram of the structure of the first pole, the first sealing ring, the end cover and the lower plastic before the end cover assembly is shown. Figure 9b for Figure 9a The schematic diagram of the structure of the first pole, the first sealing ring, the end cover and the lower plastic in the assembly process of the end cover assembly shown in FIG. Fig.9c for Figure 9b The structure diagram of the assembled first pole of the end cover assembly shown is in cooperation with the first sealing ring, the end cover and the lower plastic.

[0135] After the lower plastic 20 and the end cover 10 are assembled, the first avoidance groove 23 of the lower plastic 20 and the first sealing groove 13 of the end cover 10 form a first gap H1, and the second avoidance groove 24 of the lower plastic 20 and the second sealing groove 14 of the end cover 10 form a second gap H2.

[0136] When the first section 51 of the first sealing ring 50 is not mounted on the end cover 10 and the lower plastic 20 , it extends along the axial direction of the first sealing ring 50 , that is, the extending direction of the first section 51 is the same as the extending direction of the second section 52 . Figure 8 The first sealing ring 50 shown is in an assembled state, and the structure of the first sealing ring 50 is described in the assembled state. For the convenience of description, the first sealing ring 50 before assembly is referred to as the first sealing ring 50 before assembly.

[0137] When the first pole 30 is not installed on the end cover 10 and the lower plastic 20, the first pole 30 is in a state where the flanging operation is not performed. The first pole 30 here can be understood as the first pole 30 before assembly, and Figure 8 The first pole 30 shown is in an assembled form. For ease of description, the first pole 30 before assembly is referred to as the first pole 30 before assembly. The first pole 30 before assembly includes a first folded portion base 33a, which is arranged around the periphery of the first pole body 31, and the first folded portion base 33a is protruded from the first mounting surface 311 of the first pole body 31. The height direction of the first folded portion base 33a is consistent with the axial direction of the first pole 30, and the height of the first folded portion base 33a is greater than the height of the first protrusion 313.

[0138] The first folding portion base 33a can form the first folding portion 33 by flanging operation. The first folding portion base 33a includes a first outer annular surface and a first inner annular surface, and the first outer annular surface and the first inner annular surface are arranged opposite to each other along the thickness direction of the first folding portion base 33a. The first outer annular surface is connected to the first circumferential side surface 312 of the first pole body 31, and the orientation of the first outer annular surface is consistent with the orientation of the first circumferential side surface 312. The first outer annular surface is used to form the first sealing surface 331 of the first folding portion 33. The first inner annular surface is connected to the first mounting surface 311, and is arranged at an angle with the first mounting surface 311. The first inner annular surface is used to form the first appearance surface 332 of the first folding portion 33.

[0139] The first pole 30 before assembly also includes a first groove 35. The first groove 35 is arranged around the axial direction of the first pole 30, and the first groove 35 is formed between the first folded portion base 33a and the first protrusion 313. The first mounting surface 311 of the first pole body 31 is the surface of the groove bottom wall of the first groove 35. The first inner annular surface of the first folded portion base 33a and the outer peripheral surface of the first protrusion 313 are the surfaces of the groove side walls of the first groove 35. It can be understood that the first groove 35 is an annular groove. The first sink groove is used to release the stress received when the first folded portion 33 is formed, to avoid deformation of the first pole body 31, and to improve the structural stability of the first pole 30. The first groove 35 can also separate the first protrusion 313 and the first folded portion base 33a to prevent the first appearance surface 332 of the first folded portion 33 formed after the first folded portion base 33a is flanging to be protruding compared to the first welding surface 314 of the first protrusion 313, thereby preventing the problem of cold welding when the first pole 30 is welded to the conductor (such as a connecting plate) outside the energy storage device 1000.

[0140] Continue reading Figure 9a The first pole 30 before assembly is inserted into the first sealing hole 50a of the first sealing ring 50 before assembly, and can be inserted into the first pole through hole 25 and the first through hole 15 from bottom to top along the Z-axis direction together with the first sealing ring 50 before assembly. That is, the first flange 32 protrudes from the bottom surface 22 of the lower plastic 20, the first flange surface 322 is oriented in the same direction as the bottom surface 22 of the lower plastic 20, the first protrusion 313 and the first folded portion 33 protrude from the first surface 11 of the end cover 10, the first mounting surface 311 of the first pole body 31 is oriented in the same direction as the first surface 11 of the end cover 10, and the first flange surface 322 is oriented in the same direction as the bottom surface 22 of the lower plastic 20. The first section 51 of the first sealing ring 50 before assembly is connected to the first outer annular surface of the first folded portion base 33a, and the first section 51 and the first folded portion base 33a extend in the same direction; and the length of the first section 51 protruding from the end cover 10 is less than the length of the first folded portion base 33a protruding from the end cover 10. The first sealing ring 50 and the first pole 30 before assembly are installed on the end cover 10 and the lower plastic 20. For specific matching, please refer to Figure 8 In some embodiments, the length of the first section 51 protruding from the end cover 10 may be equal to or greater than the length of the first folded portion base 33a protruding from the end cover 10, so that the first sealing ring 50 can fully separate the first pole 30 and the end cover 10, further improving the creepage distance.

[0141] like Figure 9bAs shown, the first folding portion base 33a is subjected to a flanging operation, and the first folding portion base 33a is flipped in a direction away from the axis O1-O1 of the first pole 30 before assembly, and flipped along the direction from the end cap 10 to the lower plastic 20 to be set at an acute angle with the axis O1-O1 of the first pole 30. Exemplarily, along the direction from the end cap 10 to the lower plastic 20, the first folding portion base 33a is flipped to be set at an angle of 45 degrees with the axis O1-O1 of the first pole 30. At this time, the first folding portion base 33a presses the first section 51 in the direction of the end cap 10, so that the first section 51 is at an angle of 45 degrees with the end cap 10.

[0142] like Fig.9c As shown, the first folding portion base 33a is continuously subjected to the flanging operation, so that the first folding portion base 33a can be turned over to be perpendicular to the axis O1-O1 of the first pole 30, so as to form the first folding portion 33. At this time, the first section 51 is clamped between the first folding portion 33 and the end cover 10, and the first section 51 is connected to the first sealing surface 331 of the first folding portion 33 and the first surface 11 of the end cover 10. The first appearance surface 332 of the first folding portion 33 is flush with the first mounting surface 311 of the first pole body 31, and there is a fold (i.e., Fig.9c The first appearance surface 332 of the first folded portion 33 is flush with the bottom wall of the first groove 35, and the fold at the connection between the first groove 35 and the first folded portion 33 is visible. In some embodiments, along the direction from the end cover 10 to the lower plastic 20, the first folded portion base 33a can be turned to form an obtuse angle with the axis O1-O1 of the first pole 30. The first appearance surface 332 of the first folded portion 33 is formed to be set at an angle with the first mounting surface 311, and the first appearance surface 332 is inclined in the direction of the first flange 32, which can be understood as the first appearance surface 332 is recessed compared to the bottom wall of the first groove 35.

[0143] Since the second pole 40 of the embodiment of the present application has the same structure as the first pole 30, the assembly process diagram of the second pole 40 is similar to that of the first pole 30. Figures 9a to 9c The assembly process shown is consistent and will not be described in this application.

[0144] See also Fig.10 and Fig.11 , Fig.10 for Figure 2 The exploded schematic diagram of the second embodiment of the end cover assembly of the energy storage device shown in FIG. Fig.11 for Fig.10 The end cap assembly is shown as an exploded schematic diagram at another angle.

[0145] The end cap assembly 100 in the second embodiment is different from the end cap assembly 100 in the first embodiment in that the structures of the end cap 10 and the lower plastic 20 are different.

[0146] Specifically, Fig.10 and Fig.11 As shown, the top surface 21 of the lower plastic 20 is concavely formed to form a first avoidance groove 23 , and the bottom surface 22 is convexly formed to form a protrusion (not marked in the figure).

[0147] The lower plastic 20 further includes a limiting column 27. The limiting column 27 is convexly disposed on the top surface 21 of the lower plastic 20. The limiting column 27 is used to cooperate with the end cover 10. There are multiple limiting columns 27. Multiple limiting columns 27 are arranged at intervals along the edge of the lower plastic 20. The shape of the limiting column 27 can be, but is not limited to, a cylinder, a cone, a truncated cone, etc. Exemplarily, the number of the limiting columns 27 is twelve. The limiting column 27 is a cylinder.

[0148] like Fig.11 As shown, the end cover 10 does not include the first sealing groove 13 and the second sealing groove 14. The first through hole 15 and the second through hole 16 of the end cover 10 both penetrate the first surface 11 and the second surface 12 of the end cover 10. The end cover 10 also includes a limiting groove 17. The limiting groove 17 is recessed in the second surface 12 of the end cover 10 and is recessed in the direction of the first surface 11. There are multiple limiting grooves 17. Multiple limiting grooves 17 are arranged at intervals along the edge of the end cover 10. Each limiting groove 17 is used to accommodate a limiting column 27, and the shape of the limiting groove 17 matches the shape of the limiting column 27. Exemplarily, the number of limiting grooves 17 is twelve. The limiting groove 17 is a circular groove.

[0149] Please refer to Fig.10 , Fig.11 and Fig.12 , Fig.12 for Fig.10 A cross-sectional view of a second embodiment of a first pole and a second pole of an end cap assembly is shown.

[0150] In the second embodiment, the structure of the first pole 30 is different from that of the first embodiment, and the assembly position of the first pole 30, the end cover 10 and the lower plastic 20 is different. The first flange 32 of the first pole 30 protrudes from the first surface 11 of the end cover 10, and the orientation of the first flange surface 322 of the first flange 32 is the same as the orientation of the first surface 11. The first protrusion 313 and the first folded portion 33 of the first pole 30 protrude from the second surface 12 of the end cover 10, and the orientation of the first welding surface 314 of the first protrusion 313 and the orientation of the first appearance surface 332 of the first folded portion 33 are the same as the orientation of the second surface 12. The first protrusion 313 can be welded to the conductor (such as a pin or a tab, etc.) inside the energy storage device 1000 through the first welding surface 314 to achieve electrical connection between the first pole 30 and the conductor (such as a pin or a tab, etc.) inside the energy storage device 1000. The first flange 32 is a column, and it does not include the first step 323.

[0151] The first pole 30 further includes a first groove 35, which is arranged around the axial direction of the first pole 30, and the first groove 35 is formed between the first folded portion 33 and the first protrusion 313. The first mounting surface 311 of the first pole body 31 is the surface of the bottom wall of the first groove 35. The two opposite surfaces of the first folded portion 33 and the first protrusion 313 are the surfaces of the side walls of the groove of the first groove 35. The first groove 35 is used to separate the first protrusion 313 from the first folded portion 33, so as to prevent the first appearance surface 332 of the first folded portion 33 from being protruding compared to the first welding surface 314 of the first protrusion 313, thereby avoiding the problem of cold welding when the first pole 30 and the conductor (such as pins or pole ears, etc.) inside the energy storage device 1000 are welded.

[0152] In addition, the structure of the second pole 40 of the first embodiment is different from that of the second pole 40. In this embodiment, the assembly positions of the second pole 40, the end cover 10 and the lower plastic 20 are different. The second flange 42 of the second pole 40 protrudes from the first surface 11 of the end cover 10, and the second flange surface 422 of the second flange 42 is oriented in the same direction as the first surface 11. The second protrusion 413 and the second folded portion 43 of the second pole 40 protrude from the second surface 12 of the end cover 10, and the orientation of the second welding surface 414 of the second protrusion 413 and the orientation of the second appearance surface 432 of the second folded portion 43 are both oriented in the same direction as the second surface 12. The second protrusion 413 can be welded to the conductor (such as a pin or a tab, etc.) inside the energy storage device 1000 through the second welding surface 414 to achieve electrical connection between the second pole 40 and the conductor (such as a pin or a tab, etc.) inside the energy storage device 1000. The second flange 42 is a column, and it does not include a second step 423.

[0153] The second pole 40 also includes a second groove 45, which is arranged around the axial direction of the second pole 40, and the second groove 45 is located between the second folded portion 43 and the second protrusion 413. The second mounting surface 411 of the second pole body 41 is the surface of the bottom wall of the second groove 45. The two surfaces opposite to the second folded portion 43 and the second protrusion 413 are the surfaces of the side walls of the second groove 45. The second groove 45 is used to separate the second protrusion 413 from the second folded portion 43 to prevent the second appearance surface 432 of the second folded portion 43 from protruding from the second welding surface 414 of the second protrusion 413, thereby avoiding the problem of cold welding when the second pole 40 is welded to the conductor (such as pins or pole ears) inside the energy storage device 1000.

[0154] Please refer to Fig.10 , Fig.11 and Fig.13 , Fig.13 for Fig.10 A cross-sectional view of the end cap assembly is shown.

[0155] The lower plastic 20 and the end cover 10 are stacked in the Z-axis direction, and the lower plastic 20 and the end cover 10 are connected by ultrasonic welding. The first pole through hole 25 of the lower plastic 20 is connected to the first through hole 15 of the end cover 10 and is coaxially arranged. The notch of the first avoidance groove 23 of the lower plastic 20 is opposite to the end cover 10, and a first gap H1 is formed between the third groove bottom wall 232 of the first avoidance groove 23 and the second surface 12 of the end cover 10 around the first through hole 15, and the first gap H1 is connected to the first pole through hole 25 and the first through hole 15. The second pole through hole 26 of the lower plastic 20 is connected to the second through hole 16 of the end cover 10 and is coaxially arranged. The notch of the second avoidance groove 24 of the lower plastic 20 is opposite to the end cover 10, and a second gap H2 is formed between the fourth groove bottom wall 242 of the second avoidance groove 24 and the second surface 12 of the end cover 10 around the second through hole 16, and the second gap H2 is connected with the second pole through hole 26 and the second through hole 16. A limiting column 27 of the lower plastic 20 is accommodated in a limiting groove 17 of the end cover 10 to limit and fix the lower plastic 20 to the end cover 10.

[0156] The first pole 30, the second pole 40, the first sealing ring 50 and the second sealing ring 60 are installed together on the lower plastic 20 and the end cover 10 to form the end cover assembly 100. The first pole 30 is inserted through the first sealing hole 50a of the first sealing ring 50, and is inserted through the first pole through hole 25 of the lower plastic 20 and the first through hole 15 of the end cover 10 together with the first sealing ring 50. The first sealing ring 50 is interference fit with the end cover 10, the lower plastic 20 and the first pole 30.

[0157] The first sealing ring 50 is sleeved on the outer circumference of the first pole body 31, and then installed together with the first pole 30 on the end cover 10 and the lower plastic 20. The first flange 32 of the first pole 30, the lower plastic 20, the end cover 10 and the first folded portion 33 jointly clamp the first sealing ring 50, and the end cover 10, the lower plastic 20 and the first pole 30 compress the first sealing ring 50. The part of the first sealing ring 50 clamped between the lower plastic 20 and the end cover 10 extends into the first gap H1. The following further describes the matching relationship after assembly, and the specific assembly sequence is described later. The first sealing ring 50 is located between the first flange 32 and the first folded portion 33. The part of the end cover 10 around the first through hole 15 is located between the first section 51 and the third section 53 of the first sealing ring 50. The end cover 10 and the first section 51 and the third section 53 are clamped by the first folded portion 33 and the first flange 32.

[0158] Specifically, the first section 51 of the first sealing ring 50 is connected to the first connection surface 321 of the first flange 32 and the first surface 11 of the end cover 10. The first section 51 is interference fit with the end cover 10 and the first flange 32, which not only seals the assembly gap between the first flange 32 and the end cover 10, effectively preventing the electrolyte splashed from the outside of the energy storage device 1000 from penetrating into the first pole 30 from the assembly gap, improving the reliability of the end cover assembly 100, but also insulates the first flange 32 and the end cover 10. When the first pole 30 and the first sealing ring 50 are assembled to the end cover 10, the first flange 32 and the end cover 10 squeeze the first section 51, so that the first section 51 is deformed and extends to both ends of its width direction (i.e., one end connected to the second section 52 and one end away from the second section 52). The outer peripheral surface of the first section 51 is convex compared to the outer peripheral surface of the first flange 32, so as to increase the creepage distance from the end cover 10 to the first pole 30, thereby ensuring the safety and reliability of the end cover assembly 100.

[0159] The second section 52 of the first sealing ring 50 is connected to the first peripheral side surface 312 of the first pole body 31 and the hole wall of the second through hole 16 of the end cover 10, and is interference fit with the end cover 10 and the first pole body 31 to seal and insulate the first pole body 31 and the end cover 10, effectively preventing the electrolyte from penetrating into the first pole 30 from the assembly gap, and improving the reliability of the end cover assembly 100. The second section 52 can be compressed or not compressed, and this application does not limit this.

[0160] The third section 53 of the first sealing ring 50 is connected to the first sealing surface 331 of the first folded portion 33 and the second surface 12 of the end cover 10, and is interference fit with the end cover 10 and the first folded portion 33, so as to seal and insulate the first folded portion 33 and the end cover 10, effectively preventing the electrolyte from penetrating into the interior of the first pole 30 from the assembly gap, and improving the reliability of the end cover assembly 100. In addition, when the first pole 30 and the first sealing ring 50 are assembled to the end cover 10, the first folded portion 33 and the end cover 10 squeeze the third section 53, so that the third section 53 is deformed and extends to both ends of its width direction (i.e., one end connected to the second section 52 and one end away from the second section 52), and the third section 53 squeezes into the second gap H2 between the first avoidance groove 23 of the lower plastic 20 and the end cover 10, and connects the third groove bottom wall 232 of the first avoidance groove 23 and the second surface 12 of the end cover 10. The outer circumference of the first folded portion 33 is opposite to the hole wall of the first pole through hole 25 of the lower plastic 20, and has a certain assembly gap. It can be understood that the outer circumference of the third section 53 is protruding compared to the outer circumference of the first folded portion 33, and the third section 53 can cover the assembly gap between the outer circumference of the first folded portion 33 and the hole wall of the first pole through hole 25 of the lower plastic 20, preventing the metal powder from being present in the assembly gap and causing the end cap 10 and the first pole 30 to short-circuit, thereby improving the voltage resistance of the end cap assembly 100. In some embodiments, the third section 53 can also be squeezed into the assembly gap to seal the first pole 30 and the lower plastic 20, further increasing the sealing performance of the end cap assembly 100 and improving the reliability of the end cap assembly 100.

[0161] The second pole 40 is inserted into the second sealing hole 60a of the second sealing ring 60, and is inserted into the second pole through hole 26 of the lower plastic 20 and the second through hole 16 of the end cover 10 together with the second sealing ring 60. The second sealing ring 60 is interference fit with the end cover 10, the lower plastic 20 and the second pole 40.

[0162] The second sealing ring 60 is sleeved on the outer circumference of the second pole body 41, and then installed together with the second pole 40 on the end cover 10 and the lower plastic 20. The second flange 42 of the second pole 40, the lower plastic 20, the end cover 10 and the second folding portion 43 jointly clamp the second sealing ring 60, and the end cover 10, the lower plastic 20 and the second pole 40 compress the second sealing ring 60. The part of the second sealing ring 60 clamped between the lower plastic 20 and the end cover 10 extends into the second gap H2. The following further describes the matching relationship after assembly, and the specific assembly sequence is described later. The second sealing ring 60 is located between the second flange 42 and the second folding portion 43. The part of the end cover 10 around the second through hole 16 is located between the fourth section 61 and the sixth section 63 of the second sealing ring 60. The end cover 10 and the fourth section 61 and the sixth section 63 are clamped by the second folding portion 43 and the second flange 42.

[0163] Specifically, the fourth section 61 of the second sealing ring 60 is connected to the second connection surface 421 of the second flange 42 and the second surface 12 of the end cover 10. The fourth section 61 is interference fit with the end cover 10 and the second flange 42, which not only seals the assembly gap between the second flange 42 and the end cover 10, effectively preventing the electrolyte splashed from the outside of the energy storage device 1000 from penetrating into the first pole 30 from the assembly gap, improving the reliability of the end cover assembly 100, but also insulates the second flange 42 and the end cover 10. When the second pole 40 and the second sealing ring 60 are assembled to the end cover 10, the second flange 42 and the end cover 10 squeeze the fourth section 61, so that the fourth section 61 is deformed and extends to both ends of its width direction (i.e., one end connected to the fifth section 62 and one end away from the fifth section 62). The outer peripheral surface of the fourth section 61 is convex compared to the outer peripheral surface of the second flange 42, so as to increase the creepage distance from the end cover 10 to the second pole 40, thereby ensuring the safety of the end cover assembly 100.

[0164] The fifth section 62 of the second sealing ring 60 is connected to the second peripheral side surface 412 of the second pole body 41 and the hole wall of the second through hole 16 of the end cover 10, and is interference fit with the end cover 10 and the second pole body 41 to seal and insulate the second pole body 41 and the end cover 10, effectively preventing the electrolyte from penetrating into the first pole 30 from the assembly gap, and improving the reliability of the end cover assembly 100. The fifth section 62 can be compressed or not compressed, and this application does not limit this.

[0165] The sixth section 63 of the second sealing ring 60 is connected to the third surface of the second folded portion 43 and the second surface 12 of the end cover 10, and is interference fit with the end cover 10 and the second folded portion 43, so as to seal and insulate the second folded portion 43 and the end cover 10, effectively preventing the electrolyte from penetrating into the interior of the first pole 30 from the assembly gap, and improving the reliability of the end cover assembly 100. In addition, when the second pole 40 and the second sealing ring 60 are assembled to the end cover 10, the second folded portion 43 and the end cover 10 squeeze the sixth section 63, so that the sixth section 63 is deformed and extends to both ends of its width direction (i.e., one end connected to the fifth section 62 and one end away from the fifth section 62), and the sixth section 63 squeezes into the second gap H2 between the second avoidance groove 24 of the lower plastic 20 and the end cover 10, and connects the fourth groove bottom wall 242 of the second avoidance groove 24 and the second surface 12 of the end cover 10. The outer circumference of the second folded portion 43 is opposite to the hole wall of the second pole through hole 26 of the lower plastic 20, and has a certain assembly gap. It can be understood that the outer circumference of the sixth section 63 is protruding compared to the outer circumference of the second folded portion 43, and the sixth section 63 can cover the assembly gap between the outer circumference of the second folded portion 43 and the hole wall of the second pole through hole 26 of the lower plastic 20, preventing the metal powder from being present in the assembly gap and causing the end cap 10 and the second pole 40 to short-circuit, thereby improving the voltage resistance of the end cap assembly 100. In some embodiments, the sixth section 63 can also be squeezed into the assembly gap to seal the second pole 40 and the lower plastic 20, further increasing the sealing performance of the end cap assembly 100.

[0166] See also Fig.14 , Fig.15a and Fig.15b , Fig.14 for Fig.13 An exploded schematic diagram of a portion of the structure of the end cap assembly is shown, Fig.15a for Fig.14 The schematic diagram of the structure of the first pole with the first sealing ring and the second pole with the second sealing ring cooperating with the end cap and the lower plastic before the end cap assembly is assembled is shown. Fig.15b for Fig.15a The structure diagram of the end cap assembly after assembly is shown, in which the first pole with the first sealing ring and the second pole with the second sealing ring cooperate with the end cap and the lower plastic. It should be noted that, Fig.15a This is a cross-sectional view of the first pole and the second pole before flanging. Fig.15b for Fig.14 A cross-sectional view of a portion of the end cap assembly is shown.

[0167] In this embodiment, the first pole 30, the second pole 40, the first sealing ring 50 and the second sealing ring 60 are first assembled with the end cover 10. The first pole 30 is inserted into the first sealing hole 50a of the first sealing ring 50, and is inserted into the first through hole 15 of the end cover 10 from top to bottom along the Z-axis direction together with the first sealing ring 50. Fig.14 and Fig.15a shown.

[0168] When the third section 53 of the first sealing ring 50 is not mounted on the end cover 10 and the lower plastic 20 , it extends along the axial direction of the first sealing ring 50 , that is, the extending direction of the third section 53 is the same as the extending direction of the second section 52 . Fig.13 The first sealing ring 50 shown is in an assembled state. For ease of description, the first sealing ring 50 before assembly and the first sealing ring 50 after assembly are both referred to as the first sealing ring 50. The structure of the first sealing ring 50 is described in an assembled state.

[0169] When the first pole 30 is not installed on the end cover 10 and the lower plastic 20, the first pole 30 is not subjected to the flanging operation, and does not have the first folding portion 33. The first pole 30 here can be understood as the first pole 30 before assembly, and Fig.14 The first pole 30 shown can be understood as the assembled form. For the convenience of description, the first pole 30 before assembly and the first pole 30 after assembly are uniformly named as the first pole 30. The first pole 30 before assembly includes a first folded portion base 33a. The first folded portion base 33a surrounds the periphery of the first pole body 31 and is convexly arranged on the first mounting surface 311 of the first pole body 31.

[0170] The first folded portion base 33a can be formed into the first folded portion 33 by flanging. The first outer annular surface of the first folded portion base 33a faces away from the first groove 35. The first inner annular surface of the first folded portion base 33a is arranged at an angle with the first mounting surface 311 of the first pole body 31, and together with the outer peripheral surface of the first protrusion 313, forms the surface of the groove side wall of the first groove 35.

[0171] Continue reading Fig.15a The third section 53 of the first sealing ring 50 is connected to the first outer annular surface of the first folded portion base 33a, and the third section 53 and the first folded portion base 33a extend in the same direction; and the length of the third section 53 protruding from the end cover 10 is greater than or equal to the length of the first folded portion base 33a protruding from the end cover 10, so that the first sealing ring 50 can fully separate the first pole 30 from the end cover 10. The first sealing ring 50 and the first pole 30 are installed on the end cover 10 and the lower plastic 20. For specific matching, please refer to Fig.13In some embodiments, when the third section 53 is compressed to sufficiently separate the first pole 30 and the end cap 10, the length of the third section 53 protruding from the end cap 10 can be smaller than the length of the first folded portion base 33a protruding from the end cap 10, which can save a certain cost.

[0172] like Fig.15b As shown, the first folding portion base 33a is subjected to a flanging operation, and the first folding portion base 33a is flipped in the direction away from the axis O1-O1 of the first pole 30, and the first folding portion 33a is flipped to be perpendicular to the axis OO of the first pole 30, so as to form the first folding portion 33. At this time, the first folding portion 33 presses the third section 53 to the end cover 10, and the third section 53 is connected to the first sealing surface 331 of the first folding portion 33 and the second surface 12 of the end cover 10. The third section 53 is deformed under the pressure of the first folding portion 33 and extends to both ends of its width direction. The outer peripheral surface of the third section 53 is convex compared to the outer peripheral surface of the first folding portion 33, and squeezed into the first gap H1 to cover the assembly gap between the lower plastic 20 and the first pole 30, to prevent the metal powder from being present in the assembly gap and causing the end cover 10 and the first pole 30 to short-circuit, thereby improving the voltage resistance of the end cover assembly 100.

[0173] The first appearance surface 332 of the first folded portion 33 is convex compared to the first mounting surface 311 of the first pole body 31, and the first appearance surface 332 is concave compared to the first welding surface 314 of the first protrusion 313, so as to prevent the problem of cold welding when the first pole 30 is welded with the conductor (such as a pin or a pole ear) inside the energy storage device 1000. There is a fold between the first folded portion 33 and the first protrusion 313. In some embodiments, along the direction from the lower plastic 20 to the end cover 10, the first folded portion base 33a can be turned to be set at an obtuse angle with the axis O1-O1 of the first pole 30.

[0174] The second pole 40 is inserted into the second sealing hole 60a of the second sealing ring 60, and is inserted into the second through hole 16 of the end cover 10 from top to bottom along the Z-axis direction together with the second sealing ring 60. Fig.14 and Fig.15a shown.

[0175] When the sixth section 63 of the second sealing ring 60 is not mounted on the end cover 10 and the lower plastic 20 , it extends along the axial direction of the second sealing ring 60 , that is, the extending direction of the sixth section 63 is the same as the extending direction of the fifth section 62 . Fig.13 The second sealing ring 60 shown is in an assembled state. For ease of description, the second sealing ring 60 before assembly and the second sealing ring 60 after assembly are both referred to as the second sealing ring 60. The structure of the second sealing ring 60 is described in an assembled state.

[0176] When the second pole 40 is not installed on the end cover 10 and the lower plastic 20, the second pole 40 is not subjected to the flanging operation, and does not have the second folding portion 43. The second pole 40 here can be understood as the second pole 40 before assembly, and Fig.14 The second pole 40 shown can be understood as the assembled form. For the convenience of description, the second pole 40 before assembly and the second pole 40 after assembly are uniformly named as the second pole 40. The second pole 40 before assembly includes a second folded portion base 43a. The second folded portion base 43a surrounds the periphery of the second pole body 41 and is convexly arranged on the second mounting surface 411 of the second pole body 41.

[0177] The second folded portion base 43a can be formed into the second folded portion 43 by flanging. The second outer annular surface 441 of the second folded portion base 43a faces away from the second groove 45. The second inner annular surface 442 of the second folded portion base 43a is arranged at a 90-degree angle with the second mounting surface 411 of the second pole body 41, and together with the outer peripheral surface of the second protrusion 413, forms the surface of the groove side wall of the second groove 45.

[0178] Continue reading Fig.15a The sixth section 63 of the second sealing ring 60 is connected to the second outer annular surface 441 of the second folded portion base 43a, and the sixth section 63 and the second folded portion base 43a extend in the same direction; and the length of the sixth section 63 protruding from the end cover 10 is greater than or equal to the length of the second folded portion base 43a protruding from the end cover 10, so that the second sealing ring 60 can fully separate the second pole 40 from the end cover 10. The second sealing ring 60 and the second pole 40 are installed on the end cover 10 and the lower plastic 20. For specific matching, please refer to Fig.13 In some embodiments, when the sixth section 63 is compressed to sufficiently separate the second pole 40 and the end cap 10, the length of the sixth section 63 protruding from the end cap 10 may be smaller than the length of the second folded portion base 43a protruding from the end cap 10, which can save a certain amount of cost.

[0179] like Fig.15bAs shown, the second folding portion base 43a is subjected to a flanging operation, and the second folding portion base 43a is flipped in the direction away from the axis O2-O2 of the second pole 40, and flipped to be perpendicular to the axis O2-O2 of the second pole 40, so as to form the second folding portion 43. At this time, the second folding portion 43 presses the sixth section 63 to the end cover 10, and the sixth section 63 is connected to the second sealing surface 431 of the second folding portion 43 and the second surface 12 of the end cover 10. The sixth section 63 is deformed under the pressure of the second folding portion 43 and extends to both ends of its width direction. The outer peripheral surface of the sixth section 63 is convex compared to the outer peripheral surface of the second folding portion 43, and squeezed into the second gap H2 to cover the assembly gap between the lower plastic 20 and the second pole 40, to prevent the metal powder from being present in the assembly gap and causing the end cover 10 and the second pole 40 to short-circuit, thereby improving the voltage resistance of the end cover assembly 100.

[0180] The second appearance surface 432 of the second folded portion 43 is convexly arranged compared to the second mounting surface 411 of the second pole body 41, and the second appearance surface 432 is concavely arranged compared to the second welding surface 414 of the second protrusion 413, so as to prevent the problem of cold welding when the second pole 40 is welded with the conductor (such as a pin or a pole ear) inside the energy storage device 1000. The folds of the second folded portion 43 and the second protrusion 413 are visible. In some embodiments, along the direction from the lower plastic 20 to the end cover 10, the second folded portion base 43a can be turned over to form an obtuse angle with the axis O2-O2 of the second pole 40.

[0181] Please refer to Fig.13 and Fig.16 , Fig.16 for Fig.10 A partial exploded schematic diagram of the end cap assembly is shown.

[0182] It should be noted that Fig.16 for Fig.15aThe assembled end cap 10, the first pole 30, the second pole 40, the first sealing ring 50 and the second sealing ring 60 are assembled with the lower plastic 20 to form the end cap assembly 100. Along the Z-axis direction, the top surface 21 of the lower plastic 20 is opposite to the second surface 12 of the end cap 10, and the limiting column 27 of the lower plastic 20 is directly opposite to the notch of the limiting groove 17 of the end cap 10. The first pole through hole 25 of the lower plastic 20 is opposite to and coaxially arranged with the first through hole 15 of the end cap 10, the first pole 30 passes through the first pole through hole 25 of the lower plastic 20, and the outer peripheral surface of the first folded portion 33 is opposite to the hole wall of the first pole through hole 25 and is spaced apart. The part of the third section 53 of the first sealing ring 50 protruding from the first folded portion 33 is accommodated in the first avoidance groove 23, and is connected to the third groove bottom wall 232 of the first avoidance groove 23 and the second surface 12 of the end cap 10. The second pole through hole 26 of the lower plastic 20 is opposite to and coaxially arranged with the second through hole 16 of the end cover 10. The second pole 40 passes through the second pole through hole 26 of the lower plastic 20, and the outer peripheral surface of the second folded portion 43 is opposite to and spaced from the hole wall of the second pole through hole 26. The portion of the sixth section 63 of the second sealing ring 60 protruding from the second folded portion 43 is accommodated in the second avoidance groove 24, and is connected to the fourth groove bottom wall 242 of the second avoidance groove 24 and the second surface 12 of the end cover 10.

[0183] In the related art, the sealing structure in the end cap assembly 100 is complicated. For example, the end cap assembly 100 includes upper plastic, lower plastic, and sealing rings and other structural parts for sealing. The sealing performance of these structural parts for sealing will decrease in a low temperature environment, and even the problem of sealing failure is easy to occur, which not only reduces the reliability of the end cap assembly 100, but also makes it easy for the electrolyte outside the energy storage device 1000 to penetrate into the pole, and makes it easy for the electrolyte inside the energy storage device 1000 to reversely seep out and form white crystals, affecting the appearance of the energy storage device 1000. For example, the structural parts for sealing in the existing end cap assembly 100 are generally made of fluororubber, which is easy to become brittle in a low temperature environment (-40°C), making the sealing performance of the end cap assembly 100 fail, resulting in the defect of the energy storage device 1000.

[0184] In the embodiment of the present application, the structure of the end cap assembly 100 is simple, and only the first sealing ring 50 and the second sealing ring 60 are used as the structural parts for sealing in the end cap assembly 100, eliminating the use of plastic, saving the manufacturing cost of the end cap assembly 100, and simplifying the structure of the end cap assembly 100. The first sealing ring 50 and the second sealing ring 60 are made of low-temperature and electrolyte-resistant rubber synthetic materials such as EPDM, so that the end cap assembly 100 can maintain good sealing performance even at low temperatures, thereby improving the reliability of the end cap assembly 100.

[0185] In addition, the first folded portion 33 and the first flange 32 of the first pole 30 tightly compress the first sealing ring 50, and a good seal between the first pole 30 and the end cover 10 can be achieved without welding, preventing the electrolyte from entering the first pole 30 from the assembly gap between the first pole 30 and the end cover 10. The second folded portion 43 and the second flange 42 of the second pole 40 tightly compress the second sealing ring 60, and a good seal between the second pole 40 and the end cover 10 can be achieved without welding, preventing the electrolyte from entering the second pole 40 from the assembly gap between the second pole 40 and the end cover 10. Therefore, the end cover assembly 100 in the present application can have a good appearance and low manufacturing cost.

[0186] The above are only some embodiments and implementation methods of the present application, and the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by any person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. An end cap assembly, characterized in that: include: An end cover, wherein the end cover is provided with a through hole, and the through hole penetrates two surfaces of the end cover in a thickness direction; A lower plastic, wherein the lower plastic comprises a pole through hole, the pole through hole penetrates two surfaces of the lower plastic in a thickness direction, the lower plastic and the end cover are stacked along the thickness direction of the end cover assembly, and the through hole is connected to the pole through hole; A pole, the pole comprising a pole body and a flange, the flange being connected to one end of the pole body in a height direction, the pole body comprising a mounting surface, the mounting surface facing away from the flange, the pole further comprising a folding portion, the folding portion being protruded from the periphery of one end of the pole body and surrounding the mounting surface, the folding portion and the flange being opposite and spaced apart along the height direction of the pole, the folding portion comprising an appearance surface, the appearance surface facing away from the flange and connected to the mounting surface, a fold being provided between the appearance surface and the mounting surface, the appearance surface being flush with the mounting surface, or, along the direction from the folding portion to the flange, the mounting surface protrudes from the appearance surface; and A sealing ring is sleeved on the outer circumference of the pole body and penetrates the through hole and the pole through hole together with the pole. The end cover portion of the through hole periphery is located between the flange and the folded portion. The flange, the lower plastic, the end cover and the folded portion jointly clamp the sealing ring, and the end cover, the lower plastic and the pole compress the sealing ring.

2. The end cap assembly according to claim 1, characterized in that: The lower plastic includes a bottom surface and a top surface, the top surface and the bottom surface are arranged opposite to each other along the thickness direction of the lower plastic, the lower plastic includes an avoidance groove, the avoidance groove is recessed in the top surface and recessed toward the bottom surface, and the pole through hole penetrates the bottom wall of the avoidance groove; The end cover comprises a first surface and a second surface, the first surface and the second surface are arranged opposite to each other along the thickness direction of the end cover, and the through hole passes through the second surface and the first surface; The notch of the avoidance groove is opposite to the end cover, and there is a gap between the groove bottom wall of the avoidance groove and the second surface of the end cover at the periphery of the through hole, and the gap is connected to the pole through hole and the through hole; The portion of the sealing ring clamped between the lower plastic and the end cover extends into the gap.

3. The end cap assembly according to claim 2, characterized in that: The sealing ring comprises a first section, a second section and a third section, the second section is connected to the first section and the third section, the second section extends along the axis direction of the sealing ring, the third section and the first section both extend away from the axis of the sealing ring, and the first section and the third section are both straight sections; The second section is connected to the pole body and the end cover, the end cover around the pole is located between the first section and the third section, the end cover and the first section and the third section are clamped by the folded portion and the flange, the third section is at least partially accommodated in the gap, and blocks the assembly gap between the pole and the lower plastic.

4. The end cap assembly according to claim 3, characterized in that: A contact area between the third section and the end cover is greater than a contact area between the first section and the end cover.

5. The end cap assembly according to claim 3, characterized in that: The flange protrudes from the bottom surface of the lower plastic, and the folded portion is located on a side of the end cover facing away from the lower plastic; The first section is clamped between the folded portion and the end cover, and the outer circumferential surface of the first section is protruded compared to the outer circumferential surface of the folded portion. The third section is clamped between the flange and the end cover, and the outer circumferential surface of the third section is protruded compared to the outer circumferential surface of the flange.

6. The end cap assembly according to claim 3, characterized in that: The appearance surface of the folded portion is oriented in the same direction as the bottom surface of the lower plastic, and the flange is located on the side of the end cover facing away from the lower plastic; The first section is clamped between the flange and the end cover, and the outer circumference of the first section is protruding compared to the outer circumference of the flange. The third section is clamped between the folded portion and the end cover, and the outer circumference of the third section is protruding compared to the outer circumference of the folded portion.

7. The end cap assembly according to claim 3, characterized in that: The end cover further comprises a sealing groove, each of which is recessed on the second surface of the end cover and recessed in the direction of the first surface, and the through hole penetrates the bottom wall of the sealing groove; The notch of the avoidance groove is opposite to the notch of the sealing groove, and the gap is formed between the bottom wall of the avoidance groove and the bottom wall of the sealing groove. The gap is connected to the pole through hole and the through hole, and the third section is connected to the bottom wall of the sealing groove and the bottom wall of the avoidance groove.

8. The end cap assembly according to any one of claims 3 to 7, characterized in that: The first section has a first compression amount after compression, and the third section has a second compression amount after compression. The sum of the first compression amount and the second compression amount is 5% to 55% of the sum of the thicknesses of the first section and the third section before compression.

9. The end cap assembly according to claim 3, characterized in that: The flange includes a connecting surface, which surrounds and connects the pole body. The flange also includes a step, which is located on the outer peripheral surface of the flange and is recessed in the connecting surface. The step includes an assembly surface, the orientation of the assembly surface is consistent with the orientation of the connecting surface, and the assembly surface abuts against the bottom surface of the lower plastic.

10. The end cap assembly according to claim 1, characterized in that: The pole also includes a protrusion, which is protruding from the mounting surface of the pole body and located in the middle of the mounting surface. Along a direction perpendicular to the axis of the pole, the protrusion is spaced apart from the folded portion.

11. A method for manufacturing an end cap assembly, used for manufacturing the end cap assembly according to any one of claims 1 to 10, characterized in that: The production method comprises: Providing a sealing ring before assembly, and providing an extending direction of a first section and an extending direction of a second section of the sealing ring before assembly; A pole before assembly is provided, wherein a mounting surface of the pole body before assembly is provided with a protrusion, the pole before assembly comprises a folding portion base, the folding portion base is arranged around the periphery of the pole body, and the folding portion base protrudes from the mounting surface of the pole body, a groove is formed between the folding portion base and the protrusion, the folding portion comprises an inner annular surface, the inner annular surface is connected to the mounting surface and is arranged at an angle with the mounting surface, and the extension direction of the folding portion base is the same as the axial direction of the pole before assembly; The lower plastic and the end cover are stacked, and the pole through hole of the lower plastic and the through hole of the end cover are coaxial and connected; The pole before assembly is passed through the sealing ring before assembly, and passes through the pole through hole and the through hole in sequence with the sealing ring before assembly, the flange protrudes from the lower plastic, the third section is clamped between the end cover and the flange, the folded portion base and the first section protrude from the end cover, the first section and the folded portion base extend in the same direction, and the second section is connected between the end cover and the pole body; The folding portion base is flipped away from the end cover, and the first section is pressed toward the end cover, so that the folding portion base forms the folding portion, the inner annular surface forms the appearance surface, the folding portion and the end cover clamp the first section, and the appearance surface is flush with the mounting surface.

12. An energy storage device, characterized in that: It comprises a shell, an electrode assembly and an end cap assembly as claimed in any one of claims 1 to 10, wherein the electrode assembly is mounted in the shell, and the end cap assembly is mounted at one end of the electrode assembly and seals the shell.

13. An electrical equipment, characterized in that: It includes the energy storage device as described in claim 12, and the energy storage device supplies power to the electrical equipment.

Images