End cover assembly, energy storage device and electric equipment

Abstract

The utility model discloses an end cover assembly, an energy storage device and electric equipment. The end cover assembly comprises an end plate, a pole, a welding ring, an upper insulating part and a sealing ring. The end plate is provided with a first surface and a second surface which are oppositely arranged in the thickness direction of the end plate, and the end plate is further provided with a mounting hole penetrating through the first surface and the second surface. The pole is arranged in the mounting hole in a penetrating manner; the welding ring is positioned on one side of the second surface of the end plate and is connected to the peripheral surface of the pole in a surrounding manner; the upper insulating part is arranged on the side where the first surface of the end plate is located, surrounds the peripheral side of the pole, and is provided with an insertion section extending into the mounting hole; the sealing ring comprises an annular base part and a convex part, the annular base part sleeves the periphery of the pole and is clamped between the welding ring and the surface of the end plate in the thickness direction of the end plate, and the convex part is convexly arranged on the surface of one side, back to the welding ring, of the annular base part, extends into the mounting hole and is in contact with the insertion section.

Description

Technical Field

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

[0002] The battery includes a shell, an electrode assembly disposed in the shell, an electrolyte that immerses the electrode assembly, and an end cap assembly that seals the electrode assembly and the electrolyte in the shell. However, when the battery is in some harsh environments, the sealing performance of the end cap assembly will decrease, which will lead to electrolyte leakage. Utility Model Content

[0003] The embodiments of the present application provide an end cover assembly, an energy storage device, and an electrical device that can improve the sealing performance, so as to solve the problem of easy leakage of electrolyte existing in the related art.

[0004] The end cap assembly of the embodiment of the present application includes:

[0005] An end plate, comprising a first surface and a second surface disposed opposite to each other in a thickness direction of the end plate, and the end plate further comprising a mounting hole penetrating the first surface and the second surface;

[0006] A pole, inserted into the mounting hole;

[0007] A welding ring, located on the side of the second surface of the end plate, and surroundingly connected to the outer peripheral surface of the pole;

[0008] an upper insulating member, mounted on the side of the end plate where the first surface is located and surrounding the outer circumference of the pole, the upper insulating member having an insertion section extending into the mounting hole; and

[0009] The sealing ring includes an annular base and a raised portion, wherein the annular base is sleeved on the outer circumference of the pole and is clamped between the welding ring and the surface of the end plate along the thickness direction of the end plate, and the raised portion is protruding from the side surface of the annular base facing away from the welding ring, extends into the mounting hole, and contacts with the insertion section.

[0010] It is understandable that when an energy storage device is accidentally short-circuited, the heat generated by the short-circuit will cause the upper insulating member to deform, resulting in the destruction of the sealing integrity of the end cap assembly. In the embodiment of the present application, the sealing ring can expand when heated. Since the raised portion of the sealing ring extends into the mounting hole, the expanded raised portion can replace the upper insulating member and play a sealing role. The raised portion can maintain a tight fit with the pole and the end plate in the axial direction of the pole, thereby maintaining the sealing integrity of the overall structure of the end cap assembly and significantly reducing the risk of leakage caused by the structural gap in the axial direction of the pole of the end cap assembly; in addition, the raised portion is also in contact with the insertion section of the upper insulating member in the mounting hole, which can play a role in supporting the upper insulating member, thereby preventing the upper insulating member from softening, collapsing, and other problems due to being in a high temperature environment, and ensuring the sealing and insulation effect of the upper insulating member.

[0011] Optionally, the outer periphery of the pole has a first annular step surface facing the welding ring; a side surface of the annular base on which the protrusion is protruding is divided by the protrusion into a first contact surface and a second contact surface, the first contact surface contacts the first annular step surface, and the second contact surface contacts the end plate.

[0012] It should be noted that when the welding ring is connected to the pole by welding, there may be welding defects at the welding position formed by the welding ring and the pole, such as welding pinholes, welding holes, etc. These welding defects may become channels for electrolyte leakage. In the embodiment of the present application, the annular base is also sandwiched between the first annular step surface of the pole and the welding ring, so that the annular base is not only sealed between the end plate and the welding ring, but also sealed between the first annular step surface and the welding ring, thereby effectively blocking the communication channel between the welding position and the mounting hole, improving the air tightness of the end cover assembly, and avoiding electrolyte leakage due to welding defects at the welding position.

[0013] Optionally, the outer periphery of the pole further has a first outer peripheral side surface connected to the inner peripheral edge of the first annular step surface, and the annular base is in contact with the first outer peripheral side surface.

[0014] In the embodiment of the present application, the annular base not only contacts the first annular step surface, but also contacts the first outer peripheral side surface, so that at least two sealing surfaces are formed between the annular base and the pole, further improving the air tightness of the end cover assembly.

[0015] Optionally, the outer periphery of the pole further has a second annular step surface, and the outer periphery of the second annular step surface is connected to the inner periphery of the first annular step surface through the first outer periphery side surface;

[0016] The welding ring abuts against the second annular step surface.

[0017] In the embodiment of the present application, the welding ring abuts against the second annular step surface. When the welding ring and the pole are laser welded, the welding laser is not easy to penetrate the connection between the welding ring and the second annular step surface and burn the sealing ring and the upper insulating part, thereby avoiding the sealing ring and the upper insulating part from failing due to the high temperature of the laser, and further improving the airtightness of the end cover assembly.

[0018] Optionally, the outer periphery of the pole further has a second outer peripheral side surface, and the second outer peripheral side surface is connected to the inner periphery of the second annular step surface;

[0019] The welding ring is sleeved on the outer periphery of the second outer peripheral side surface and is welded to the pole.

[0020] Optionally, the outer periphery of the pole further has a third outer peripheral side surface connected to the outer peripheral edge of the first annular step surface, and the protrusion is sandwiched between the third outer peripheral side surface and the hole wall of the mounting hole.

[0021] In the embodiment of the present application, the protrusion is sealed between the third outer peripheral side surface and the hole wall of the mounting hole, which can further enhance the air tightness of the end cover assembly.

[0022] Optionally, the end plate also has a recessed groove, which is recessed from the second surface to the first surface along the thickness direction of the end plate, and the mounting hole passes through the bottom surface of the recessed groove; the annular base is arranged in the recessed groove and is in contact with the first annular step surface and the bottom surface of the groove at the same time.

[0023] Optionally, the first annular step surface is flush with the groove bottom surface.

[0024] In the embodiment of the present application, since the first annular step surface is flush with the groove bottom surface, when the annular base contacts the first annular step surface and the groove bottom surface, the inner and outer sides of the annular base are subjected to more consistent forces, thereby ensuring the overall sealing performance of the annular base.

[0025] Optionally, the first contact surface and the second contact surface are both annular structures.

[0026] Optionally, the ring width of the first contact surface is smaller than or equal to the ring width of the second contact surface.

[0027] It can be understood that the position where the first contact surface contacts the first annular step surface forms a first annular sealing surface, and the annular width of the annular sealing surface is substantially the same as the annular width of the first contact surface. Similarly, the position where the second contact surface contacts the end plate forms a second annular sealing surface, and the annular width of the second annular sealing surface is substantially the same as the width of the second contact surface. By designing the annular width of the first contact surface to be less than or equal to the annular width of the second contact surface, the annular width of the second annular sealing surface formed by the annular base and the end plate can be made sufficiently large when the size of the annular base remains unchanged, thereby ensuring the sealing between the end plate and the welding ring.

[0028] Optionally, the protrusion is an annular structure and surrounds the outer circumference of the pole.

[0029] In the embodiment of the present application, the protrusion can play a limiting role in the radial direction of the pole, and the sealing ring can maintain a stable shape in a high temperature environment, which can prevent the pole from being affected by external forces and displacing in the radial direction of the pole, thereby improving the durability and reliability of the energy storage device.

[0030] Optionally, a contact position between the protrusion and the insertion section forms a bonding surface, and the bonding surface is parallel to the first surface.

[0031] Optionally, the height of the protrusion ranges from 1 / 3 to 2 / 3 of the depth of the mounting hole.

[0032] In the embodiment of the present application, by designing the height of the protrusion to be 1 / 3 to 2 / 3 of the depth of the mounting hole, when the sealing ring is heated and expands, the expanded protrusion will not protrude from the first surface of the end plate due to being too high, nor will it be too short to maintain a close fit with the pole and the end plate.

[0033] Optionally, it further comprises a lower insulating member, which is installed on the side where the second surface of the end plate is located;

[0034] The lower insulating member comprises an insulating ring sleeved on the outer periphery of the annular base, the insulating ring is arranged between the end plate and the welding ring, and contacts with the outer peripheral surface of the annular base.

[0035] In the embodiment of the present application, the inner circumference of the annular base contacts the pole, the outer circumference of the annular base contacts the insulating ring, and the protrusion contacts the insertion section of the upper insulating member, so that the sealing ring is more firmly arranged between the end plate and the welding ring, thereby significantly improving the sealing performance of the sealing ring.

[0036] The energy storage device of the embodiment of the present application includes:

[0037] A housing, comprising a receiving cavity having an opening;

[0038] an electrode assembly, accommodated in the accommodating cavity; and

[0039] The end cover assembly described in any of the above items closes the opening of the accommodating cavity.

[0040] The electrical equipment of the embodiment of the present application includes the above-mentioned energy storage device, and the energy storage device supplies power to the electrical equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 Shown is a structural schematic diagram of a household energy storage system.

[0042] Figure 2 Shown is a schematic diagram of an exploded view of a single cell according to an embodiment of the present application.

[0043] Figure 3 Shown is a schematic diagram of an exploded view of an end cover assembly according to an embodiment of the present application.

[0044] Figure 4 What is shown is a three-dimensional schematic diagram of a pole according to an embodiment of the present application.

[0045] Figure 5 Shown is a top view of an end cap assembly according to an embodiment of the present application.

[0046] Figure 6 Shown is the Figure 5 Partial section view along the AA cutting line.

[0047] Figure 7 Shown is a three-dimensional schematic diagram of a sealing ring according to an embodiment of the present application.

[0048] Figure 8 Shown is a schematic diagram of an electrical device according to an embodiment of the present application.

[0049] The reference numerals are described as follows:

[0050] 1. Energy storage device; 2. Electric energy conversion device; 3. User load; 4. Electrical equipment;

[0051] 10. Shell; 11. Accommodating chamber; 12. Opening; 20. Electrode assembly; 30. End cap assembly;

[0052] 100, end plate; 101, first surface; 102, second surface; 103, mounting hole; 105, air leakage hole; 106, injection hole; 107, sink; 107a, bottom surface of the sink;

[0053] 200, pole; 201, first annular step surface; 202, first peripheral side surface; 203, third peripheral side surface; 204, second annular step surface; 205, second peripheral side surface; 210, column; 220, flange ring;

[0054] 300, upper insulating member; 310, insertion section; 320, extension section; 330, surrounding section;

[0055] 400, sealing ring; 410, annular base; 411, first contact surface; 412, second contact surface; 420, raised portion;

[0056] 500, welding ring;

[0057] 600, lower insulating member; 610, insulating ring;

[0058] 700, explosion-proof valve;

[0059] 800. Bonding surface. DETAILED DESCRIPTION

[0060] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this application will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their detailed description will be omitted.

[0061] It is understood that the terms "including" and "having" and any variations thereof in the embodiments of the present application are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or components that are inherent to these processes, methods, products, or devices.

[0062] 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 way or convert it into another form of energy, and then release it in a specific form of energy based on future application needs.

[0063] At present, energy storage (i.e. energy storage) has a wide range of application scenarios, including power generation side energy storage, grid side energy storage, renewable energy grid-connected energy storage and user side energy storage. The corresponding types of energy storage devices include:

[0064] (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;

[0065] (2) The main operating mode of small and medium-sized energy storage cabinets used in industrial and commercial energy storage scenarios (banks, shopping malls, etc.) on the user side and small household energy storage boxes used in home energy storage scenarios on the user side is "peak shaving and valley filling". Since there is a large price difference in electricity charges at peak and valley locations according to electricity demand, after users have energy storage equipment, 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 equipment is discharged for use to achieve the purpose of saving electricity bills. In addition, in remote areas and areas prone to natural disasters such as earthquakes and hurricanes, the existence of household energy storage devices is equivalent to users providing themselves and the power grid with backup power, eliminating the inconvenience caused by frequent power outages due to disasters or other reasons.

[0066] Take the household energy storage scenario in user-side energy storage as an example to illustrate. Figure 1 A household energy storage system is shown, which includes an energy storage device 1 and an electric energy conversion device 2 (such as a photovoltaic panel), and a user load 3 (such as a street lamp, household appliances, etc.). The energy storage device 1 is a small energy storage box that can be mounted on an outdoor wall by wall hanging. Specifically, the electric energy conversion device 2 can convert solar energy into electric energy during the period of low electricity prices, and store it through the energy storage device 1, and then supply the user load 3 for use during the peak electricity price, or supply the user load 3 for use when the power grid is out of power / power outage.

[0067] In combination with the above-mentioned situation of storing energy by physical or electrochemical means, taking electrochemical energy storage as an example, the energy storage device 1 includes at least one group of chemical batteries, using the chemical elements in the chemical batteries as energy storage media, so as to realize the charging and discharging process through the chemical reaction or change of the energy storage medium. In simple terms, the electric energy generated by light energy and wind energy is stored in at least one group of chemical batteries through the chemical reaction or change of the energy storage medium, and when the use of external electric energy reaches a peak, the electric energy stored in at least one group of chemical batteries is released for use through the chemical reaction or change of the energy storage medium, or transferred to a place where electric energy is scarce for use.

[0068] The embodiment of the present application provides an energy storage device 1, which can be but is not limited to a single cell (secondary battery), a battery module, a battery pack, a battery system, etc. composed of single cells. As for the single cell, it can be a lithium-ion battery, a sodium-ion battery, a sodium-lithium-ion battery, a lithium metal battery, a sodium metal battery, a lithium-sulfur battery, a magnesium-ion battery, a nickel-hydrogen battery, a nickel-cadmium battery, a lead-acid battery, etc. The single cell can be cylindrical, flat, rectangular, etc., and the embodiment of the present application does not limit this. Next, taking the energy storage device 1 as a rectangular single cell as an example, the energy storage device 1 is explained in detail.

[0069] like Figure 2As shown, the energy storage device 1 of the embodiment of the present application includes a housing 10, an electrode assembly 20 and an end cap assembly 30. The housing 10 includes a housing cavity 11 having an opening 12, the electrode assembly 20 is accommodated in the housing cavity 11, and the end cap assembly 30 is connected to the housing 10 and closes the opening 12 of the housing cavity 11.

[0070] The shell 10 may be a cylindrical structure with an opening 12 at one end, and the energy storage device 1 includes an end cover assembly 30, which seals the opening 12. Of course, the shell 10 may also be a cylindrical structure with openings 12 at both ends, and the energy storage device 1 may include an end cover assembly 30 and a cover plate, or the energy storage device 1 includes two end cover assemblies 30, so that one end cover assembly 30 and one cover plate, or two end cover assemblies 30 can seal the two openings 12 of the shell 10 respectively.

[0071] Optionally, the housing 10 may be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite shell) or an aluminum-plastic film.

[0072] Among them, the electrode assembly 20 includes a positive electrode sheet, a negative electrode sheet and a separator. The single cell mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive electrode collector and a positive electrode active material layer. The positive electrode active material layer is coated on the surface of the positive electrode collector. The positive electrode collector not coated with the positive electrode active material layer protrudes from the positive electrode collector coated with the positive electrode active material layer. The positive electrode collector not coated with the positive electrode active material layer serves as a positive electrode tab. Taking lithium-ion batteries as an example, the material of the positive electrode collector can be aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide. The negative electrode sheet includes a negative electrode collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode collector. The negative electrode collector not coated with the negative electrode active material layer protrudes from the negative electrode collector coated with the negative electrode active material layer. The negative electrode collector not coated with the negative electrode active material layer serves as a negative electrode tab. The material of the negative electrode collector can be copper, and the negative electrode active material can be carbon or silicon. The material of the isolation film may be PP or PE, etc. In addition, the electrode assembly 20 may be a winding structure or a stacked structure, but the embodiment of the present application is not limited thereto.

[0073] like Figure 3 As shown, the end cover assembly 30 includes an end plate 100 and an explosion-proof valve 700. The end plate 100 is connected to the housing 10 and seals the opening 12 of the accommodating chamber 11. The connection between the end plate 100 and the housing 10 can be welding, but is not limited to this. The shape of the end plate 100 is adapted to the shape of the opening 12. In the embodiment of the present application, the shape of the opening 12 is rectangular, so the shape of the end plate 100 is also rectangular.

[0074] The end plate 100 has a gas leakage hole 105, and the gas leakage hole 105 penetrates the end plate 100 along the thickness direction of the end plate 100. The explosion-proof valve 700 is connected to the side surface of the end plate 100 facing the electrode assembly 20, and closes the gas leakage hole 105. The explosion-proof valve 700 is used to explode and discharge the gas generated in the accommodating cavity 11 of the shell 10 when the gas pressure of the energy storage device 1 reaches a certain pressure threshold, so as to avoid the battery from bulging and exploding, thereby improving the safety of the energy storage device 1.

[0075] The end plate 100 is also provided with an injection hole 106, which penetrates the end plate 100 along the thickness direction of the end plate 100. After the end cover assembly 30 seals the opening 12 of the accommodating cavity 11, the electrolyte can be injected into the accommodating cavity 11 of the housing 10 through the injection hole 106. After the electrolyte is injected, the injection hole 106 can be sealed with a seal (not shown in the figure) to prevent leakage of the electrolyte.

[0076] like Figure 3 As shown, the end cap assembly 30 further includes a pole 200 , an upper insulating member 300 , a lower insulating member 600 , a welding ring 500 and a sealing ring 400 .

[0077] The end plate 100 has a first surface 101 and a second surface 102 disposed opposite to each other along its thickness direction. The end plate 100 also has a mounting hole 103, and the mounting hole 103, the air leakage hole 105, and the injection hole 106 all penetrate the first surface 101 and the second surface 102. The pole 200 is installed in the mounting hole 103. The upper insulating member 300 surrounds the outer circumference of the pole 200 and is penetrated in the mounting hole 103, and is used to insulate the pole 200 and the end plate 100. The lower insulating member 600 is installed on the side where the second surface 102 of the end plate 100 is located, and is used to insulate the pole 200 and the end plate 100. The welding ring 500 is located on the side where the second surface 102 of the end plate 100 is located, and is connected to the outer circumferential surface of the pole 200, for example, by welding. The sealing ring 400 is sleeved on the outer circumference of the pole 200, and is used to seal the gap between the pole 200 and the hole wall of the mounting hole 103.

[0078] In one embodiment, the end plate 100 may be a plain aluminum sheet, but is not limited thereto. The upper insulating member 300 and the lower insulating member 600 are made of insulating material, such as plastic.

[0079] like Figures 4 to 6 As shown, the pole 200 includes a column 210 and a flange ring 220, and the column 210 is installed in the mounting hole 103 of the end plate 100. The welding ring 500 is connected to one end of the column 210, and the flange ring 220 is connected to the other end of the column 210. For example, the flange ring 220 surrounds and is connected to the outer peripheral surface of one end of the column 210 extending from the first surface 101.

[0080] like Figure 4As shown, the outer periphery of the column 210 is provided with a first outer peripheral side surface 202, a second outer peripheral side surface 205 and a third outer peripheral side surface 203 in an annular shape. In the direction from the first surface 101 to the second surface 102 of the end plate 100, the third outer peripheral side surface 203, the first outer peripheral side surface 202 and the second outer peripheral side surface 205 are arranged in sequence, and the diameters gradually decrease, so as to form a step surface on the outer periphery of the column 210.

[0081] The outer periphery of the column 210 is further provided with a first annular step surface 201 and a second annular step surface 204. The first outer peripheral side surface 202 is connected to the third outer peripheral side surface 203 through the first annular step surface 201, that is, the inner periphery of the first annular step surface 201 is connected to the first outer peripheral side surface 202, and the outer periphery of the first annular step surface 201 is connected to the third outer peripheral side surface 203. The first outer peripheral side surface 202 is connected to the second outer peripheral side surface 205 through the second annular step surface 204, that is, the inner periphery of the second annular step surface 204 is connected to the second outer peripheral side surface 205, and the outer periphery of the second annular step surface 204 is connected to the first outer peripheral side surface 202.

[0082] In one embodiment, the first peripheral side surface 202, the second peripheral side surface 205, and the third peripheral side surface 203 are parallel to each other. Of course, in other embodiments, the first peripheral side surface 202, the second peripheral side surface 205, and the third peripheral side surface 203 may also have an angle between each other.

[0083] In the embodiment of the present application, the first outer peripheral side surface 202 , the second outer peripheral side surface 205 , and the third outer peripheral side surface 203 are all parallel to the axis L of the pole 200 .

[0084] In addition, the first annular step surface 201 can be perpendicular to the third peripheral side surface 203; and / or, the first annular step surface 201 can be perpendicular to the first peripheral side surface 202; and / or, the second annular step surface 204 can be perpendicular to the first peripheral side surface 202; and / or, the second annular step surface 204 can be perpendicular to the second peripheral side surface 205.

[0085] like Figure 6 As shown, the upper insulator 300 includes an insertion section 310, an extension section 320 and a surrounding section 330. The extension section 320 is installed on the side where the first surface 101 of the end plate 100 is located, and is sandwiched between the flange ring 220 of the pole 200 and the end plate 100. The insertion section 310 is connected to one end of the extension section 320 close to the column 210 and extends into the mounting hole 103. The surrounding section 330 is connected to one end of the extension section 320 away from the column 210 and surrounds the outer circumference of the flange ring 220.

[0086] like Figure 6 and Figure 7As shown, the sealing ring 400 includes an annular base 410 and a protrusion 420. The annular base 410 is sleeved on the outer periphery of the pole 200 and is sandwiched between the welding ring 500 and the surface of the end plate 100 along the thickness direction of the end plate 100, and is used to seal the gap between the welding ring 500 and the end plate 100. The protrusion 420 is protruding from the side surface of the annular base 410 facing away from the welding ring 500, and extends into the mounting hole 103, and contacts the insertion section 310 of the upper insulating member 300.

[0087] It is understandable that when an accidental short circuit occurs in the energy storage device, the heat generated by the short circuit may cause the upper insulating member 300 to deform, thereby destroying the sealing integrity of the end cap assembly 30 . In the embodiment of the present application, the sealing ring 400 can expand thermally when heated. Since the protrusion 420 of the sealing ring 400 extends into the mounting hole 103, the expanded protrusion 420 can replace the upper insulating member 300 to play a sealing role. The protrusion 420 can maintain a close fit with the pole 200 and the end plate 100 in the axial direction of the pole 200, thereby maintaining the sealing integrity of the overall structure of the end cover assembly 30, and significantly reducing the risk of leakage of the end cover assembly 30 due to the structural gap in the axial direction of the pole 200; in addition, the protrusion 420 is also in contact with the insertion section 310 of the upper insulating member 300 in the mounting hole 103, which can play a role in supporting the upper insulating member 300, thereby preventing the upper insulating member 300 from softening, collapsing, and other problems due to being in a high temperature environment, thereby ensuring the sealing and insulation effect of the upper insulating member 300.

[0088] like Figure 6 As shown, the first annular step surface 201 of the pole 200 faces the welding ring 500 , and the annular base 410 is sandwiched between the first annular step surface 201 and the welding ring 500 .

[0089] For example, Figure 6 and Figure 7 As shown, the one side surface of the annular base 410 protrudes with the protrusion 420 and is divided into a first contact surface 411 and a second contact surface 412 by the protrusion 420. The first contact surface 411 contacts the first annular step surface 201, and the second contact surface 412 contacts the end plate 100.

[0090] It should be noted that when the welding ring 500 and the pole 200 are connected by welding, welding defects such as welding pinholes and welding holes may exist at the welding position 900 formed by the welding ring 500 and the pole 200, and these welding defects may become channels for electrolyte leakage.

[0091] In the embodiment of the present application, the annular base 410 is clamped between the first annular step surface 201 of the pole 200 and the welding ring 500, so that the annular base 410 is not only sealed between the end plate 100 and the welding ring 500, but also sealed between the first annular step surface 201 and the welding ring 500, thereby effectively blocking the communication channel between the welding position 900 and the mounting hole 103, improving the air tightness of the end cover assembly 30, and avoiding leakage of electrolyte due to welding defects at the welding position 900.

[0092] As an example, the first contact surface 411 and the second contact surface 412 are both annular structures. Of course, in other embodiments, the first contact surface 411 and the second contact surface 412 may also be arc-shaped.

[0093] When the first contact surface 411 and the second contact surface 412 are both annular structures, the ring width of the first contact surface 411 is smaller than or equal to the ring width of the second contact surface 412 .

[0094] It can be understood that the position where the first contact surface 411 contacts the first annular step surface 201 forms a first annular sealing surface, and the annular width of the annular sealing surface is substantially the same as the annular width of the first contact surface 411. Similarly, the position where the second contact surface 412 contacts the end plate 100 forms a second annular sealing surface, and the annular width of the second annular sealing surface is substantially the same as the width of the second contact surface 412. By designing the annular width of the first contact surface 411 to be less than or equal to the annular width of the second contact surface 412, the annular width of the second annular sealing surface formed by the annular base 410 and the end plate 100 can be made sufficiently large when the size of the annular base 410 remains unchanged, thereby ensuring the sealing between the end plate 100 and the welding ring 500.

[0095] like Figure 6 As shown, the annular base 410 is in contact with the first outer peripheral side 202 .

[0096] In the embodiment of the present application, the annular base 410 not only contacts the first annular step surface 201 , but also contacts the first outer peripheral side surface 202 , so that at least two sealing surfaces are formed between the annular base 410 and the pole 200 , further improving the air tightness of the end cover assembly 30 .

[0097] Please continue reading Figure 6 The welding ring 500 is sleeved on the outer periphery of the second outer peripheral side surface 205 , and the welding ring 500 abuts against the second annular step surface 204 .

[0098] In the embodiment of the present application, the welding ring 500 is in contact with the second annular step surface 204. When the welding ring 500 and the pole 200 are laser welded, the laser is not easy to penetrate the connection between the welding ring 500 and the second annular step surface 204 and burn the sealing ring 400 and the upper insulating member 300, thereby avoiding the sealing ring 400 and the upper insulating member 300 from failing due to the high temperature of the laser, and further improving the airtightness of the end cover assembly 30.

[0099] like Figure 6 As shown, the protrusion 420 is sandwiched between the third outer peripheral side surface 203 and the hole wall of the mounting hole 103 .

[0100] In the embodiment of the present application, the protrusion 420 is sealed between the third outer peripheral side surface 203 and the hole wall of the mounting hole 103 , which can further enhance the air tightness of the end cover assembly 30 .

[0101] In one embodiment, if Figure 7 As shown, the protrusion 420 is an annular structure and surrounds the outer circumference of the pole 200. In this way, the protrusion 420 can limit the position of the pole 200 in the radial direction. The sealing ring 400 can maintain a stable shape in a high temperature environment, which can prevent the pole 200 from being affected by external forces and displacing in the radial direction of the pole 200, thereby improving the durability and reliability of the energy storage device.

[0102] Of course, in other embodiments, the protrusion 420 may further include a plurality of sub-protrusions (not shown in the figure), and the plurality of sub-protrusions extend into the mounting hole 103 and are arranged along the circumference of the pole 200 .

[0103] The shape of the sub-protrusions may be a block structure, an arc-shaped strip structure, etc., and this application does not impose any particular limitation on this.

[0104] Please return to Figure 6 The end plate 100 also has a recessed groove 107, which is recessed from the second surface 102 to the first surface 101 along the thickness direction of the end plate 100, and the mounting hole 103 passes through the groove bottom surface 107a of the recessed groove 107. The annular base 410 is disposed in the recessed groove 107 and contacts the first annular step surface 201 and the groove bottom surface 107a at the same time.

[0105] Furthermore, the first annular step surface 201 is flush with the groove bottom surface 107 a.

[0106] In the embodiment of the present application, since the first annular step surface 201 is flush with the groove bottom surface 107a, when the annular base 410 contacts the first annular step surface 201 and the groove bottom surface 107a, the inner and outer sides of the annular base 410 are subjected to more consistent forces, thereby ensuring the overall sealing performance of the annular base 410.

[0107] like Figure 6As shown, the lower insulator 600 has an insulating ring 610 sleeved on the outer periphery of the annular base 410, the insulating ring 610 is located in the sink 107 and is disposed between the end plate 100 and the welding ring 500. The inner circumference of the insulating ring 610 contacts the outer circumference of the annular base 410.

[0108] In the embodiment of the present application, the inner circumference of the annular base 410 contacts the pole 200, the outer circumference of the annular base 410 contacts the insulating ring 610, and the protrusion 420 contacts the insertion section 310 of the upper insulating member 300, so that the sealing ring 400 is more firmly arranged between the end plate 100 and the welding ring 500, thereby significantly improving the sealing performance of the sealing ring 400.

[0109] like Figure 6 As shown, the contact position between the protrusion 420 and the insertion section 310 forms a bonding surface 800 , and the bonding surface 800 is parallel to the first surface 101 and the second surface 102 .

[0110] Furthermore, the height of the protrusion 420 ranges from 1 / 3 to 2 / 3 of the depth of the mounting hole 103. By designing the height of the protrusion 420 to be 1 / 3 to 2 / 3 of the depth of the mounting hole 103, when the sealing ring 400 is heated and thermally expands, the expanded protrusion 420 will not protrude from the first surface 101 of the end plate 100 due to being too high, nor will it be too short to maintain a close fit with the pole 200 and the end plate 100.

[0111] like Figure 8 As shown, the embodiment of the present application further provides an electric device 4, which can be an energy storage device, a vehicle, an energy storage container, etc. The electric device 4 includes the energy storage device 1 described in the above embodiment, and the energy storage device 1 supplies power to the electric device 4. In this way, for the electric device 4 including the energy storage device 1 described above, the working stability of the electric device 4 can be improved, the probability of the electric device 4 downtime can be reduced, and the safety of the use of the electric device 4 can be improved.

[0112] In summary, the end cap assembly 30, the energy storage device 1 and the electrical equipment 4 of the embodiment of the present application have at least the following advantages and beneficial effects:

[0113] The sealing ring 400 of the end cover assembly 30 of the embodiment of the present application includes an annular base 410 and a protrusion 420. The annular base 410 is squeezed by the first annular step surface 201, the end plate 100 and the welding ring 500. The protrusion 420 extends into the mounting hole 103 and contacts the insertion section 310 of the upper insulating member 300. The sealing ring 400 adopts the above-mentioned structural design to ensure that it can still maintain better sealing performance in a high temperature environment, so as to form a sealing fit with the pole 200 and the end plate 100 in the axial direction of the pole 200, thereby ensuring the overall airtightness of the end cover assembly 30.

[0114] It is understandable that the various embodiments / implementations provided in the present application can be combined with each other without causing any contradiction, and will not be illustrated one by one here.

[0115] In the application embodiments, the terms "first", "second", and "third" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance; the term "plurality" refers to two or more, unless otherwise expressly defined. The terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the application embodiments can be understood according to the specific circumstances.

[0116] In the description of the application embodiments, it should be understood that the directions or positional relationships indicated by the terms "up", "down", "left", "right", "front", "back", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the application embodiments and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation, and therefore, should not be understood as a limitation on the application embodiments.

[0117] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the application embodiment. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0118] The above are only preferred embodiments of the application embodiments and are not intended to limit the application embodiments. For those skilled in the art, the application embodiments may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the application embodiments shall be included in the protection scope of the application embodiments.

Claims

1. An end cap assembly, characterized in that: include: An end plate, comprising a first surface and a second surface disposed opposite to each other in a thickness direction of the end plate, and the end plate further comprising a mounting hole penetrating the first surface and the second surface; A pole, inserted into the mounting hole; A welding ring, located on the side of the second surface of the end plate, and surroundingly connected to the outer peripheral surface of the pole; An upper insulating member, mounted on the side of the end plate where the first surface is located and surrounding the outer circumference of the pole, the upper insulating member having an insertion section extending into the mounting hole; as well as The sealing ring includes an annular base and a raised portion, wherein the annular base is sleeved on the outer circumference of the pole and is clamped between the welding ring and the surface of the end plate along the thickness direction of the end plate, and the raised portion is protruding from the side surface of the annular base facing away from the welding ring, extends into the mounting hole, and contacts with the insertion section.

2. The end cap assembly according to claim 1, characterized in that: The outer periphery of the pole has a first annular step surface facing the welding ring; A side surface of the annular base on which the protrusion is protruding is divided into a first contact surface and a second contact surface by the protrusion. The first contact surface contacts the first annular step surface, and the second contact surface contacts the end plate.

3. The end cap assembly according to claim 2, characterized in that: The outer periphery of the pole further has a first outer peripheral side surface connected to the inner peripheral edge of the first annular step surface, and the annular base is in contact with the first outer peripheral side surface.

4. The end cap assembly according to claim 3, characterized in that: The outer periphery of the pole further comprises a second annular step surface, and the outer periphery of the second annular step surface is connected to the inner periphery of the first annular step surface through the first outer periphery side surface; The welding ring abuts against the second annular step surface.

5. The end cap assembly according to claim 4, characterized in that: The outer periphery of the pole also has a second outer peripheral side surface, and the second outer peripheral side surface is connected to the inner peripheral edge of the second annular step surface; The welding ring is sleeved on the outer periphery of the second outer peripheral side surface and is welded to the pole.

6. The end cap assembly according to claim 2, characterized in that: The outer periphery of the pole further has a third outer peripheral side surface connected to the outer peripheral edge of the first annular step surface, and the protrusion is sandwiched between the third outer peripheral side surface and the hole wall of the mounting hole.

7. The end cap assembly according to claim 2, characterized in that: The end plate also has a recessed groove, which is recessed from the second surface to the first surface along the thickness direction of the end plate, and the mounting hole passes through the bottom surface of the recessed groove; the annular base is arranged in the recessed groove and is in contact with the first annular step surface and the bottom surface of the groove at the same time.

8. The end cap assembly according to claim 7, characterized in that: The first annular step surface is flush with the groove bottom surface.

9. The end cap assembly according to claim 2, characterized in that: The first contact surface and the second contact surface are both annular structures.

10. The end cap assembly according to claim 9, characterized in that: The ring width of the first contact surface is smaller than or equal to the ring width of the second contact surface.

11. The end cap assembly according to claim 1, characterized in that: The protrusion is an annular structure and surrounds the outer circumference of the pole.

12. The end cap assembly according to claim 1, wherein: A contact position between the protrusion and the insertion section forms a bonding surface, and the bonding surface is parallel to the first surface.

13. The end cap assembly according to claim 1, wherein: The height of the protrusion is in the range of 1 / 3 to 2 / 3 of the depth of the mounting hole.

14. The end cap assembly according to any one of claims 1 to 13, characterized in that: It also includes a lower insulating member installed on the side where the second surface of the end plate is located; The lower insulating member comprises an insulating ring sleeved on the outer periphery of the annular base, the insulating ring is arranged between the end plate and the welding ring, and contacts with the outer peripheral surface of the annular base.

15. An energy storage device, characterized in that: include: A housing, comprising a receiving cavity having an opening; An electrode assembly is accommodated in the accommodating cavity; as well as The end cap assembly according to any one of claims 1 to 14, wherein the end cap assembly closes the opening of the accommodating cavity.

16. An electrical equipment, characterized in that: It includes the energy storage device as described in claim 15, and the energy storage device supplies power to the electrical equipment.

Images