End cover assembly, energy storage device and electric equipment

Abstract

The invention discloses an end cover assembly, an energy storage device and electric equipment, the end cover assembly comprises an end cover, a pole, a heat insulation ring, a pressing block and lower plastic, and the pole comprises a pole body and a flange connected to one end of the pole body; the end cover comprises a mounting groove and a mounting hole; the lower plastic comprises a lower plastic body and an assembly hole penetrating through the lower plastic body; the heat insulation ring comprises a through hole, the end cover and the lower plastic are stacked in the thickness direction of the end cover assembly, the second surface of the end cover abuts against the lower plastic, and the assembling hole and the mounting hole are opposite and communicated. The post body penetrates through the assembly hole and the installation hole, the pressing block is located on the side, back on to the end cover, of the lower plastic and fixed to the end, away from the flange, of the post body, and the heat insulation ring is arranged on the post body in a sleeving mode through the penetrating hole, extends into the installation hole and the assembly hole and is blocked between the lower plastic and the post body. The heat insulation ring separates the end cover from the pole body, and in the thickness direction of the end cover assembly, the heat insulation ring separates the plastic cement below the pressing block.

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, and an electrical equipment. Background Art

[0002] As demand for secondary energy storage devices grows, so too do expectations for energy density, reliability, sealing performance, and cost. In existing end cap assemblies, the high temperatures associated with welding the pressure ring to the terminal post can damage non-metallic components, potentially reducing sealing performance or causing damage to the end cap assembly, reducing its reliability. Summary of the Invention

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

[0004] The present application provides an end cap assembly for an energy storage device, the end cap assembly comprising: an end cap, a pole, an insulation ring, a pressing block and a lower plastic.

[0005] The pole includes a pole body and a flange connected to one end of the pole body;

[0006] The end cover includes 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 end cover further includes a mounting groove and a mounting hole, the mounting groove is recessed in the second surface, and the mounting hole passes through the bottom wall of the mounting groove and the first surface;

[0007] The lower plastic includes a lower plastic body, and the lower plastic also includes an assembly hole, and the assembly hole passes through two surfaces of the lower plastic body in the thickness direction;

[0008] The thermal insulation ring includes perforations,

[0009] The end cover and the lower plastic are stacked along the thickness direction of the end cover assembly, the second surface of the end cover abuts against the lower plastic, and the assembly hole is opposite to and connected to the mounting hole;

[0010] Along the thickness direction of the end cover assembly, the pole body is passed through the assembly hole and the mounting hole, the pressing block is located on the side of the lower plastic facing away from the end cover, and the pressing block is fixed to the end of the pole body away from the flange.

[0011] The thermal insulation ring is sleeved on the pole body through the through-hole, and extends into the mounting hole and the assembly hole. The thermal insulation ring is blocked between the lower plastic and the pole body, and the thermal insulation ring is blocked between the end cover and the pole body. In the thickness direction of the end cover assembly, the thermal insulation ring is blocked between the pressure block and the lower plastic.

[0012] The heat-insulating ring comprises a barrier body, a barrier sub-ring, and a supporting platform. The barrier sub-ring protrudes from a surface of the barrier body and forms the through-hole with the barrier body. The supporting platform is protruded from the surface of the barrier body and is connected to and surrounds the barrier sub-ring.

[0013] The barrier ring extends into the gap between the mounting hole and the pole body. In the thickness direction of the end cover assembly, the end cover around the mounting hole abuts against the supporting platform, the lower plastic around the assembly hole abuts against the barrier body, and the pressure block abuts against the side of the barrier body facing away from the lower plastic.

[0014] Wherein, in the thickness direction of the end cover assembly, the projection of the outer contour of the pressing block overlaps with the projection of the outer contour of the barrier body, or the projection of the outer contour of the barrier body completely covers the projection of the outer contour of the pressing block.

[0015] Wherein, the thermal insulation ring is made of ceramic material.

[0016] The end cover assembly further includes a sealing ring, which is sleeved on the pole body and clamped between the flange and the end cover. In the thickness direction of the end cover assembly, the barrier ring supports the sealing ring.

[0017] Wherein, the connection between the flange and the pole body is an arc-shaped surface;

[0018] The sealing ring includes a sealing surface, a first connecting surface, and a second connecting surface. The first connecting surface and the second connecting surface are arranged opposite to each other along the thickness direction of the second section. The sealing surface connects the first connecting surface and the second connecting surface. The first connecting surface, the second connecting surface, and the sealing surface all face the pole body. The first connecting surface is an inclined surface and is inclined toward the pole body, or the connection between the first connecting surfaces is an arc surface.

[0019] The sealing surface abuts against the circumferential surface of the pole body, the first connecting surface abuts against the arcuate surface, and the blocking sub-ring abuts against the second connecting surface and makes the second connecting surface recessed into the sealing ring.

[0020] The end cap assembly includes an upper plastic, which includes an upper plastic body and a flange. The upper plastic body has an inner ring surface. The flange is protruding from the inner ring surface and located on one side of the upper plastic body. The upper plastic body and the flange form a through hole. The pole body is provided with the through hole. Along the radial direction of the pole body, the upper plastic body protrudes and surrounds the outer periphery of the flange. The flange is clamped between the flange and the end cap.

[0021] The flange includes a supporting surface, which is a curved surface and abuts against a side of the sealing ring facing away from the pole body.

[0022] Among them, the surface of the lower plastic body is also recessed with an avoidance groove, the avoidance hole passes through the bottom wall of the avoidance groove, the end cover also includes a mounting groove recessed on the second surface, the supporting platform is located in the mounting groove and abuts against the bottom wall of the mounting groove, and the blocking body is partially located in the avoidance groove and abuts against the bottom wall of the avoidance groove.

[0023] The present application provides an energy storage device, comprising a shell, a battery cell and the end cover assembly, wherein the shell comprises an opening and a receiving cavity, the battery cell is accommodated in the shell, the end cover assembly is sealed in the opening, and the battery cell comprises a tab, which is connected to the pole.

[0024] The present application provides an electrical device, which includes the energy storage device described above, and the energy storage device is used to supply power to the electrical device.

[0025] The present invention utilizes laser welding to connect the pressure ring and the terminal. The instantaneous temperature generated during welding is high, while the melting point of the lower plastic is lower than that of the pressure ring and the terminal. A heat-insulating ring is positioned between the lower plastic and the pressure ring, insulating the pressure ring and the terminal. This heat generated during welding between the pressure ring and the terminal is isolated by the heat-insulating ring, preventing the lower plastic from melting due to the high temperatures associated with welding the pressure ring and the terminal, thereby ensuring the reliability of the end cap assembly. Furthermore, the sealing ring does not contact the pressure ring, preventing deformation of the sealing ring caused by the high temperature of the pressure ring and thus compromising sealing performance. The sealing ring is positioned on the surface of the end cap facing away from the lower plastic. The gap between the first terminal, the end cap, and the lower plastic only needs to be sealed by the sealing ring, eliminating the need for additional sealing between the first pressure ring and the first terminal. Therefore, even if the laser welding of the first pressure ring and the first terminal exhibits weld defects such as hot spots, the end cap can still function normally while maintaining other performance characteristics, reducing the defect rate and, in turn, minimizing sealing issues in the end cap assembly caused by poor welding between the first pressure ring and the first terminal. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the implementation. Obviously, the drawings described below are only some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained like these drawings without any creative work.

[0027] Figure 1 This is an application scenario diagram of the energy storage device provided in an embodiment of the present application;

[0028] Figure 2 yes Figure 1 A schematic structural diagram of the energy storage device shown;

[0029] Figure 3 yes Figure 2 A schematic structural diagram of an end cap assembly of an energy storage device shown;

[0030] Figure 4 yes Figure 3 Schematic diagram of the exploded structure of the end cap assembly shown;

[0031] Figure 5 yes Figure 3 A schematic diagram of the exploded structure of the end cap assembly shown in another angle;

[0032] Figure 6 yes Figure 4 A schematic diagram of the cross-sectional structure of the pole of the end cap assembly shown;

[0033] Figure 7 yes Figure 4 A schematic diagram of the cross-sectional structure of the upper plastic of the end cap assembly shown;

[0034] Figure 8 yes Figure 4 A schematic cross-sectional structure diagram of the sealing ring of the end cover assembly shown;

[0035] Figure 9 yes Figure 4 A schematic cross-sectional structure diagram of the thermal insulation ring of the end cover assembly shown;

[0036] Figure 10 yes Figure 3 Schematic diagram of the cross-sectional structure of the end cover assembly shown.

[0037] The nouns corresponding to the reference numerals in the figures are: energy storage system 5000, electric energy conversion device 4500, wind energy conversion device 4000, second electrical equipment 3000, energy storage device 1000, end cover assembly 100, end cover 10, first surface 11, second surface 12, first mounting groove 13, first protrusion 131, second mounting groove 14, second protrusion 141, first mounting hole 15, second mounting hole 16, first pole 21, first pole body 211, first flange 212, first curved surface 213, first step 214, first recess 2122, second pole 22, second pole body body 221, second flange 222, second recess 2222, second arc-shaped surface 223, second step 224, first upper plastic 31, first upper plastic body 311, first inner ring surface 3111, first flange 312, first abutting surface 3123, first through hole 313, second upper plastic 32, second upper plastic body 321, second inner ring surface 3211, second flange 322, second abutting surface 3223, second through hole 323, first sealing ring 41, first section 411, first insulating surface 4111, second insulating surface 4112, first end surface 4113, second section 412, first Connecting surface 4121, second connecting surface 4122, first sealing surface 4123, first sealing hole 413, second sealing ring 42, third section 421, third insulating surface 4211, fourth insulating surface 4212, second end surface 4213, fourth section 422, third connecting surface 4221, fourth connecting surface 4222, second sealing surface 4223, second sealing hole 423, lower plastic 50, lower plastic body 51, third surface 511, fourth surface 512, first avoidance groove 52, second avoidance groove 53, first boss 54, second boss 55, first assembly hole 58, second assembly hole 59, First pressing block 61, first upper surface 611, first lower surface 612, first hole 613, second pressing block 62, second upper surface 621, second lower surface 622, second hole 623, first thermal insulation ring 45, first blocking body 451, first blocking sub-ring 452, first supporting platform 453, first mating surface 4511, second mating surface 4512, first through-hole 454, second thermal insulation ring 46, second blocking body 461, second blocking sub-ring 462, second supporting platform 463, second through-hole 464, third mating surface 4621, fourth mating surface 4622, shell 800, gap A. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0039] In this application, unless otherwise expressly specified and limited, terms such as "installed", "connected", "connected", and "fixed" should be understood in a broad sense. For example, the connection may be fixed, detachable, or integrated; the connection may be mechanical, electrical, or communicative; the connection may be direct or indirect through an intermediate medium; the connection may be internal to two elements or an interaction relationship between two elements, unless otherwise clearly specified and limited.

[0040] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0041] Taking electrochemical energy storage as an example, this solution provides an energy storage device with a group of chemical batteries inside. The energy storage device 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 medium. Simply put, the electricity generated by wind and solar energy is stored in the chemical batteries. When the use of external electricity reaches its peak, the stored electricity is released for use, or transferred to places where electricity is scarce for use.

[0042] Currently, 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 energy storage device types include:

[0043] (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, achieving load matching of electricity in time and space, enhancing the ability to absorb renewable energy, and are of great significance in grid system backup, alleviating peak load power supply pressure, and peak and frequency regulation;

[0044] (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. Since there is a large price difference in electricity prices 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, they release the electricity in the energy storage equipment for use, thereby saving electricity costs.

[0045] 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 energy storage devices can be understood as electrical equipment.

[0046] See also Figure 1 The energy storage device 1000 provided in the embodiment of the present application is applied to an energy storage system 5000, which includes an electric energy conversion device 4500 (photovoltaic panel), a wind energy conversion device 4000 (windmill), a first electric user (grid), a second electric user 3000 (base station) and an energy storage device 1000. The energy storage system 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 electric energy conversion device can convert solar energy into electric energy during periods of low electricity prices, and the energy storage device 1000 is used to store the electric energy and supply it to the first electric user or the second electric user during peak electricity consumption, or to supply power when the first electric user or the second electric user is out of power / outage. The second electric energy conversion device 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 electric user or the second electric user during peak electricity consumption, or to supply power when the first electric user or the second electric user is out of power / outage. Among them, the transmission of electric energy can be carried out using high-voltage cables.

[0047] It should be noted that the first electric device, the second electric device and other devices including the energy storage device 1000 can be understood as electric devices.

[0048] See also Figure 2 , the energy storage device 1000 may include but is not limited to single cells, battery modules, battery packs, battery systems, etc. It is understandable that 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-acid) 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 a square battery. Among them, the square battery is a secondary battery. It should be noted that the number of energy storage devices 1000 may be several, and several energy storage devices 1000 are connected in series or in parallel. In this embodiment, "several" refers to two or more.

[0049] The energy storage device 1000 includes an end cap assembly 100, a housing 800, and a battery cell (not shown). The housing 800 includes an opening (not shown) and a receiving cavity (not shown). The battery cell includes a positive electrode tab (not shown) and a negative electrode tab (not shown). The end cap assembly 100 includes a first electrode 21 and a second electrode 22. The positive electrode tab is welded to the first electrode 21, and the negative electrode tab is welded to the second electrode 22. The battery cell is placed in the receiving cavity of the housing 800, and the end cap assembly 100 is sealed to the opening of the housing 800.

[0050] For ease of description, in this application, the thickness direction of the energy storage device 1000 is defined as the Z-axis direction, the width direction is defined as the X-axis direction, and the length direction is defined as the Y-axis direction. The X-axis, Y-axis, and Z-axis directions are perpendicular to each other. The directional terms such as "upper", "top", "lower", "bottom", "left", and "right" mentioned in the description of the embodiments of this application are based on the instructions in the appendix. Figure 2 The description of the orientation shown does not constitute a limitation on the actual application scenario of the energy storage device 1000. A certain tolerance is allowed for the terms "same", "equal" or "parallel" used in the following text.

[0051] Please refer to Figure 3 、 Figure 4 and Figure 5 In this embodiment, the end cover assembly 100 includes an end cover 10, a first pole 21 and a second pole 22, a first upper plastic 31 and a second upper plastic 32, a first sealing ring 41 and a second sealing ring 42, a first thermal insulation ring 45, a second thermal insulation ring 46, a lower plastic 50, a first pressing block 61 and a second pressing block 62.

[0052] The first electrode 21 can be defined as a positive electrode and the second electrode 22 as a negative electrode, or the first electrode 21 can be defined as a negative electrode and the second electrode 22 as a positive electrode. For example, the first electrode 21 is a negative electrode and the second electrode 22 is a positive electrode. The first electrode 21 and the second electrode 22 are located at opposite ends of the end cap assembly 100 in the longitudinal direction. The end cap 10 and the lower plastic 50 are stacked along the thickness direction of the end cap assembly 100.

[0053] The first upper plastic component 31, the first sealing ring 41, the first thermal insulation ring 45, and the first pressure block 61 are placed over the first pole 21 and are all connected to the end cap 10 and the lower plastic component 50. The first pole 21 is insulated and sealed from the end cap 10 by the cooperation of the first sealing ring 41, the first upper plastic component 31, and the first thermal insulation ring 45. The second upper plastic component 32, the second sealing ring 42, the second thermal insulation ring 46, and the second pressure block 62 are placed over the second pole 22 and are all connected to the end cap 10 and the lower plastic component 50. The second pole 22 is insulated and sealed from the end cap 10 by the cooperation of the second upper plastic component 32, the second sealing ring 42, and the second thermal insulation ring 46.

[0054] The first pressing block 61 includes a first upper surface 611 and a first lower surface 612. The first upper surface 611 and the first lower surface 612 are disposed opposite each other along the thickness direction of the first pressing block 61. The first pressing block 61 also includes a first hole 613, which extends through the first upper surface 611 and the first lower surface 612 along the thickness direction of the first pressing block 61, for allowing the first terminal 21 to pass through. In this embodiment, the first pressing block 61 can be made of copper.

[0055] The structure of the second pressing block 62 is the same as that of the first pressing block 61. The second pressing block 62 includes a second upper surface 621 and a second lower surface 622. The second upper surface 621 and the second lower surface 622 are arranged opposite to each other along the thickness direction of the second pressing block 62. The second pressing block 62 also includes a second hole 623. The second hole 623 passes through the second upper surface 621 and the second lower surface 622 along the thickness direction of the second pressing block 62, and is used for the second pole 22 to pass through. In other embodiments, the structure of the second pressing block 62 may be different from that of the first pressing block 61. In this embodiment, the second pressing block 62 may be made of copper.

[0056] Please also refer to Figure 4 and Figure 5 The end cap 10 is a substantially rectangular plate. In this embodiment, the end cap 10 is a plain aluminum sheet. The end cap 10 includes a first surface 11 and a second surface 12. The first surface 11 and the second surface 12 are disposed opposite to each other along the thickness direction of the end cap 10.

[0057] The end cover 10 includes a first mounting groove 13 and a second mounting groove 14, which are respectively located at opposite ends of the length direction of the end cover 10. The first mounting groove 13 is a roughly rectangular groove body, and the opening of the first mounting groove 13 is located on the second surface 12. The first mounting groove 13 is recessed from the second surface 12 toward the first surface 11, and a first protrusion 131 is formed on the first surface 11. In this embodiment, the structure of the second mounting groove 14 is the same as that of the first mounting groove 13. The opening of the second mounting groove 14 is located on the second surface 12. The second mounting groove 14 is recessed from the second surface 12 toward the first surface 11, and a second protrusion 141 is formed on the first surface 11.

[0058] The end cap 10 also includes a first mounting hole 15 and a second mounting hole 16. The first mounting hole 15 and the second mounting hole 16 are respectively located at both ends of the length direction of the end cap 10. Along the thickness direction of the end cap 10, the first mounting hole 15 passes through the first protrusion 131 and the bottom wall of the first mounting groove 13, that is, passes through the first surface 11 and the bottom wall of the first mounting groove 13. The second mounting hole 16 passes through the bottom wall of the second mounting groove 14 and the second protrusion 141. That is, the second mounting hole 16 passes through the first surface 11 and the bottom wall of the second mounting groove 14. In other embodiments, the structure of the first mounting groove 13 and the structure of the second mounting groove 14 may also be different.

[0059] like Figure 4 and Figure 5The lower plastic 50 includes a lower plastic body 51. The lower plastic body 51 is generally a rectangular thin plate. The length of the lower plastic body 51 is the same as the length of the end cap 10, and the width of the lower plastic body 51 is comparable to the length of the end cap 10, with a certain tolerance range allowed. The lower plastic body 51 includes a third surface 511 and a fourth surface 512, and the third surface 511 and the fourth surface 512 are arranged opposite to each other along the thickness direction of the lower plastic body 51. In this embodiment, the lower plastic 50 can be made of plastic.

[0060] The lower plastic portion 50 includes a first avoidance groove 52 and a second avoidance groove 53. The first avoidance groove 52 and the second avoidance groove 53 are located on opposite sides of the length of the lower plastic portion 50. The openings of the first avoidance grooves 52 are both located on the fourth surface 512. The first avoidance grooves 52 are recessed from the fourth surface 512 toward the third surface 511.

[0061] In this embodiment, the structure of the second avoidance groove 53 is the same as that of the first avoidance groove 52. The opening of the second avoidance groove 53 is located on the fourth surface 512. The second avoidance groove 53 is recessed from the fourth surface 512 toward the third surface 511. The lower plastic 50 also includes a first boss 54 and a second boss 55. The first boss 54 and the second boss 55 are protruding from the third surface 511 and are respectively located at opposite ends of the length direction of the lower plastic body 51. The first avoidance groove 52 is recessed from the fourth surface 512 toward the third surface 511 and protrudes from the third surface 511 to form the first boss 54. The shape of the first boss 54 matches the shape of the first mounting groove 13. In this embodiment, the structure of the second boss 55 is the same as that of the first boss 54. The second avoidance groove 53 is recessed from the fourth surface 512 toward the third surface 511 and protrudes from the third surface 511 to form the second boss 55.

[0062] The lower plastic member 50 further includes a first assembly hole 58 and a second assembly hole 59. The first assembly hole 58 extends through the first boss 54 and the bottom wall of the first avoidance groove 52, and is used to pass the first pole 21 through the first assembly hole 58. The second assembly hole 59 extends through the second boss 55 and the bottom wall of the second avoidance groove 53, and is used to pass the second pole 22 through the second assembly hole 59. In other embodiments, the structures of the first assembly hole 58 and the second assembly hole 59 may differ.

[0063] See also Figure 6The first pole 21 includes a first pole body 211 and a first flange 212. Along the height of the first pole 21, the first pole body 211 is connected to a surface on one side of the first flange 212. In this embodiment, the first flange 212 is a plate having a first surface and a second surface, which are disposed opposite each other along the thickness direction of the first flange 212. The first pole body 211 is projecting from the second surface of the first flange 212. The first flange 212 and the first pole body 211 are coaxially arranged. In one embodiment, the connection between the first pole body 211 and the first flange 212 is a first curved surface 213. It is understood that the first pole body 211 and the first flange 212 are connected in an arc shape, with the second surface connected to the outer cylindrical surface of the first pole body 211 via the first curved surface 213. In other embodiments, the connection between the first pole body 211 and the first flange 212 can be a right angle. In this embodiment, the first pole body 211 has a hexagonal cross-section, and the first flange 212 is a hexagonal plate. The cross-sectional area of ​​the first flange 212 is greater than the cross-sectional area of ​​the first pole body 211 .

[0064] The first flange 212 includes a first recess 2122, which is recessed at the edge of the second surface. The first recess 2122 is recessed from the second surface toward the first surface and extends through the periphery of the first flange 212. The first pole 21 also includes a first step 214, which is located at the end of the first pole body 211 away from the first flange 212. The first step 214 is arranged around the outer circumference of the first pole body 211, and the first step 214 is formed by partially recessing the end of the first pole body 211 toward the central axis of the first pole body 211. The cross-section of the first pole body 211 is roughly T-shaped. The first step 214 is arranged away from the first flange 212. The first step 214 is used to cooperate with the first pressure block 61.

[0065] In this embodiment, the first electrode 21 is the negative electrode. The first electrode 21 can be formed by integral stamping or machining. In this embodiment, the first electrode 21 can be a copper-aluminum composite structure manufactured through a stamping process. This simple processing method offers high production efficiency, effectively reducing the production cost of the first electrode 21. For example, the first electrode 21 is made of copper and aluminum. The first flange 212 and the first step 214 are integrally formed.

[0066] In this embodiment, the structure of the second pole 22 is similar to that of the first pole 21. Figure 7The difference is that the material of the second pole 22 is different from that of the first pole 21. In this embodiment, the second pole 22 is the positive pole. The second pole 22 includes a second pole body 221 and a second flange 222. The structure of the second pole body 221 is the same as that of the first pole body 211. In one embodiment, the connection between the second pole body 221 and the second flange 222 forms a second curved surface 223.

[0067] In this embodiment, the second flange 222 includes a third surface (not labeled) and a fourth surface (not labeled), and the third surface and the fourth surface are arranged opposite to each other along the thickness direction of the second flange 222. The second flange 222 includes a second recess 2222, which is recessed at the edge of the fourth surface. The second recess 2222 is recessed from the fourth surface toward the third surface and extends through the periphery of the second flange 222. The second pole 22 also includes a second step 224. The structure of the second step 224 is the same as that of the first step 214. The second step 224 is used to cooperate with the second pressure block 62. The second step 224 can be made of copper and formed by stamping.

[0068] See also Figure 7 The first upper plastic member 31 includes a first upper plastic body 311 and a first flange 312. The first upper plastic body 311 includes a first inner ring surface 3111 and a first outer ring surface (not shown). The first inner ring surface 3111 and the first outer ring surface are disposed opposite each other in the radial direction of the first upper plastic body 311. The first inner ring surface 3111 is the surface of the first upper plastic body 311 facing the central axis, and the first outer ring surface is the surface of the first upper plastic body 311 facing away from the central axis.

[0069] The first flange 312 protrudes from the first inner ring surface 3111 and is located on one side of the first upper plastic body 311. In this embodiment, the cross-section of the first upper plastic body 311 is generally L-shaped. The first flange 312 includes two mounting surfaces (not shown) and a first abutting surface 3123. The two mounting surfaces are arranged opposite each other along the thickness direction of the first flange 312, one of which is connected to the first inner ring surface 3111, and the other to the first outer ring surface. The first abutting surface 3123 connects between the two mounting surfaces and is the surface of the first flange 312 facing away from the first upper plastic body 311. The first abutting surface 3123 is a curved surface. In this embodiment, the cross-sectional profile of the first abutting surface 3123 of the first flange 312 is trapezoidal.

[0070] The first upper plastic part 31 also includes a first through-hole 313. The first through-hole 313 is used to allow the first pole 21 to pass through. The first upper plastic body 311 and the first flange 312 together form the first through-hole 313. It will be appreciated that the first inner ring surface 3111, the first mounting surface, and the first abutting surface 3123 collectively form the walls of the first through-hole 313. In this embodiment, the first upper plastic part 31 utilizes a separate injection molding process, enabling the simultaneous formation of multiple first upper plastic parts 31 using a single mold with multiple cavities. This reduces the material usage of the first upper plastic part 31, reducing costs by 80%.

[0071] In this embodiment, the structure of the second upper plastic member 32 is identical to that of the first upper plastic member 31 , comprising a second upper plastic body 321 , a second flange 322 , and a second through-hole 323 . The second through-hole 323 is configured to allow the second pole 22 to pass through. The connection between the second upper plastic body 321 and the second flange 322 can be described in detail with reference to the first upper plastic member 31 , and will not be further elaborated here. The second upper plastic body 321 includes a second inner annular surface 3211 . The second flange 322 includes two mounting surfaces (not shown) and a second abutting surface 3223 . In this embodiment, the cross-sectional profile of the second abutting surface 3223 is trapezoidal.

[0072] See also Figure 8 , the first sealing ring 41 includes a first section 411 and a second section 412. It should be noted that the dotted lines in the figure are only for clearly distinguishing the first section 411 and the second section 412. The first section 411 includes a first insulating surface 4111, a second insulating surface 4112 and a first end face 4113. The first insulating surface 4111 and the second insulating surface 4112 are arranged opposite to each other along the thickness direction of the first section 411. The first end face 4113 is the surface of the first section 411 facing away from the second section 412. The first end face 4113 is connected between the first insulating surface 4111 and the second insulating surface 4112. Along the radial direction of the sealing ring, the second section 412 is connected to the inner periphery of the first section 411 (the side facing away from the first end face 4113). The second section 412 includes a first connecting surface 4121, a second connecting surface 4122 and a first sealing surface 4123. The first connecting surface 4121 and the second connecting surface 4122 are disposed opposite each other along the thickness direction of the second section 412. Both the first connecting surface 4121 and the second connecting surface 4122 are connected to the first section 411. The first sealing surface 4123 is connected between the first connecting surface 4121 and the second connecting surface 4122. The first sealing surface 4123 is the surface of the second section 412 that is away from the first section 411. The first sealing surface 4123 and the first end surface 4113 are disposed opposite each other in the radial direction of the first sealing ring 41. In this embodiment, the first connecting surface 4121 is connected to the first insulating surface 4111, and the second connecting surface 4122 is connected to the second insulating surface 4112. The first connecting surface 4121 and the second connecting surface 4122 are inclined surfaces, and both are inclined toward the central axis of the first sealing ring 41.

[0073] The first sealing ring 41 also includes a first sealing hole 413. The first section 411 and the second section 412 together define the first sealing hole 413. The second section 412 is closer to the axis of the first sealing hole 413 than the first section 411. In this embodiment, the first connecting surface 4121 and the second connecting surface 4122 are both inclined toward the axis of the first sealing hole 413. The first connecting surface 4121, the second connecting surface 4122, and the first sealing surface 4123 collectively form the wall of the first sealing hole 413. It should be noted that along the thickness direction of the first sealing ring 41, the thickness of the second section 412 is less than that of the first section 411. In this embodiment, the first sealing ring 41 is made of plastic or rubber and has deformation tension. In this embodiment, the first sealing ring 41 is a closed hexagonal ring. The cross-section of the first section 411 is rectangular, and the cross-section of the second section 412 is approximately trapezoidal. In other embodiments, the cross-section of the second section 412 is approximately trapezoidal, stepped, or shaped.

[0074] In this embodiment, the structure of the second sealing ring 42 is the same as that of the first sealing ring 41. The second sealing ring 42 includes a third section 421 and a fourth section 422. The third section 421 includes a third insulating surface 4211, a fourth insulating surface 4212, and a second end surface 4213. The fourth section 422 includes a third connecting surface 4221, a fourth connecting surface 4222, and a second sealing surface 4223. The second sealing ring 42 also includes a second sealing hole 423. The connection relationship and positional relationship of the specific structure of the second sealing ring 42 can be referred to the first sealing ring 41, and will not be elaborated here. It can be understood that the first sealing ring 41 and the second sealing ring 42 can also be ring bodies with rectangular cross-sections.

[0075] See also Figure 9The first thermal insulation ring 45 is a closed ring made of ceramic. The first thermal insulation ring 45 includes a first barrier body 451, a first barrier sub-ring 452 and a first supporting platform 453. The first barrier body 451 and the first barrier sub-ring 452 are connected and enclose a first through-hole 454. The first supporting platform 453 is protruded from the first barrier body 451 and surrounds the outer circumference of the first barrier sub-ring 452. Specifically, the first barrier body 451 is an annular sheet, which includes a first mating surface 4511 and a second mating surface 4512. The first mating surface 4511 and the second mating surface 4512 are arranged in opposite directions along the axial direction of the first through-hole 454. The first barrier sub-ring 452 is protruded from the inner circumference of the first mating surface 4511. The first barrier sub-ring 452 is an annular protrusion. The inner annular surface of the first barrier sub-ring 452 is connected to the inner annular surface of the first barrier body 451 and together form the hole wall of the first through-hole 454. The inner annular surface of the first barrier body 451 connects the first mating surface 4511 and the second mating surface 4512. The first support platform 453 protrudes from the first mating surface 4511. The first support platform 453 surrounds the first blocking sub-ring 452 and is connected to the first blocking sub-ring 452. The surface of the first support platform 453 faces the same direction as the first mating surface 4511. Along the thickness direction of the first thermal insulation ring 45, the height of the first blocking sub-ring 452 protruding from the first mating surface 4511 is greater than the height of the first support platform 453. The first support platform 453 and the first barrier body 451 are arranged in a stepped manner. The surface of the first support platform 453 faces the surface of the first mating surface 4511, which is a stepped surface. In this embodiment, the angle between the first blocking sub-ring 452, the first support platform 453, and the first barrier body 451 is a right angle.

[0076] In this embodiment, the structure of the second thermal isolation ring 46 is identical to that of the first thermal isolation ring 45, comprising a second barrier body 461, a second barrier sub-ring 462, and a second support platform 463. The second barrier body 461 is an annular sheet, comprising a third mating surface 4621 and a fourth mating surface 4622. The second thermal isolation ring 46 also includes a second through-hole 464. The detailed structural details of the second thermal isolation ring 46 can be found in the description of the first thermal isolation ring 45 and are not further elaborated here.

[0077] See also Figure 10The end cap 10 and the lower plastic 50 are assembled, stacked along the Z-axis. The second surface 12 of the end cap 10 faces the lower plastic 50 and abuts the third surface 511 of the lower plastic body 51. The first boss 54 of the lower plastic 50 cooperates with the first mounting groove 13 of the end cap 10. That is, the first boss 54 is accommodated in the first mounting groove 13. The first mounting hole 15 and the first assembly hole 58 of the lower plastic 50 are opposite and coaxially arranged. The aperture of the first mounting hole 15 is smaller than that of the first assembly hole 58. The top surface of the first boss 54 abuts the bottom wall of the first mounting groove 13. The first mounting groove 13 still has some space for accommodating a portion of the first thermal insulation ring 45.

[0078] It can be understood that the thermal insulation ring is mounted on the pole body, extending into the mounting hole and the assembly hole. The thermal insulation ring is located between the lower plastic and the pole body, between the end cap and the pole body, and, in the thickness direction of the end cap assembly, between the pressure block and the lower plastic. Specifically, the first upper plastic 31 and the first sealing ring 41 are sequentially mounted on the outer circumference of the first pole body 211. The first pole body 211 is sequentially passed through the first mounting hole 15 of the end cap 10 and the first assembly hole 58 of the lower plastic 50. The first upper plastic body 311 surrounds the first flange 212, and the first inner ring surface 3111 of the first upper plastic body 311 abuts the outer circumferential surface of the first flange 212. Along the height direction of the first pole 21, the end of the first upper plastic body 311 away from the first flange 312 abuts the first recess 2122 of the first flange 212. The first flange 312 is located between the first flange 212 and the end cap 10 and is used to insulate the first pole 21 from the end cap 10. The first flange 312 abuts the second surface of the first flange 212 and the first surface 11 of the end cap 10. The first abutting surface 3123 is spaced apart from the outer circumference of the first pole body 211. The first sealing ring 41 is located between the first abutting surface 3123 of the first upper plastic 31 and the outer circumference of the first pole body 211 and is clamped between the first flange 212 and the end cap 10.

[0079] When the first pressing block 61 is not fixed to the first terminal 21 and is not compressing the first sealing ring 41, the first end surface 4113 of the first section 411 opposes (and may be spaced apart from or in contact with) the first abutting surface 3123 of the first flange 312. The first section 411 is located between the first flange 212 and the end cap 10, insulating the end cap 10 from the lower plastic 50 and sealing the entire end cap assembly 100. The first insulating surface 4111 of the first section 411 abuts the second surface of the first flange 212, while the second insulating surface 4112 abuts the first surface 11 of the end cap 10. The second section 412 opposes the gap A between the end cap and the first terminal body 211, that is, the gap A between the wall of the first mounting hole 15 and the first terminal body 211. The first sealing surface 4123 of the second section 412 abuts against the outer peripheral surface of the first pole body 211 , the first connecting surface 4121 of the second section 412 faces the first flange 212 (may or may not contact), and the second connecting surface 4122 faces the gap.

[0080] The first thermal insulation ring 45 is inserted into the first terminal body 211 by the lower plastic 50 through the first through-hole 454. The first barrier ring 452 extends into the gap A and abuts against the second section 412. The first support platform 453 is located within the first mounting groove 13 and abuts against the bottom wall of the first mounting groove 13. The first barrier body 451 is partially located in the first avoidance groove 52, and a portion of the first mating surface 4511 abuts against the bottom wall of the first avoidance groove 52. The first pressure block 61 is inserted into the first terminal body 211, with the first upper surface 611 of the first pressure block 61 abutting the first step 214 and the first barrier body 451. The outer circumference of the first terminal body 211 abuts the walls of the first sealing hole 413, the first hole 613, and the first through-hole 454. In the thickness direction of the end cover assembly 100, the projection of the outer contour of the first pressing block 61 overlaps with the projection of the outer contour of the first blocking body 451, or the projection of the outer contour of the first blocking body 451 completely covers the projection of the outer contour of the first pressing block 61, so as to ensure that the first pressing block 61 is completely blocked from the lower plastic 50 (the location of the first avoidance groove and its periphery are not in contact with the first pressing block 61).

[0081] The first pressing block 61 and the first pole 21 are fixed and electrically connected via laser welding. Along the thickness direction of the end cap assembly 100, a mutual force is generated between the first flange 212, the end cap 10, the lower plastic 50, the first sealing ring 41, and the first thermal insulation ring 45. Specifically, the first flange 212 and the first pressing block 61 clamp and secure the end cap 10, the lower plastic 50, the first thermal insulation ring 45, and the first sealing ring 41. The first sealing ring 41 is subjected to an extrusion force along the thickness direction of the end cap assembly 100. The first sealing ring 41 is deformed by the extrusion. In the radial direction of the first sealing ring, it abuts the first pole 21 and the first upper plastic. In the axial direction, the second section 412 of the first sealing ring 41 abuts the first thermal insulation ring 45 and the first pole 21. The term "abutment" refers to contact with a mutual force.

[0082] When the first sealing ring 41 is squeezed and deformed, the first sealing ring 41 abuts against the first abutting surface 3123 of the first upper plastic 31 (the first abutting surface 3123 is a curved surface to improve sealing performance), the outer circumferential surface of the first pole body 211, the first flange 212, the first surface 11 of the end cover 10, and the first thermal insulation ring 45.

[0083] In this embodiment, the assembly relationship and effects of the second upper plastic 32, the second sealing ring 42, the second pole 22, the second thermal insulation ring 46, the end cover 10 and the lower plastic 50 can all refer to the assembly relationship of the first pole 21, the first sealing ring 41, the first upper plastic 31, the end cover 10 and the lower plastic 50 described above; they will not be repeated here.

[0084] Because in the prior art, a sealing ring is disposed between the end cap and the pressure block, and a gap exists between the upper plastic and the end cap, and weld cracks often occur between the pole and the pressure block during welding, the first sealing ring of this embodiment is disposed on the surface of the end cap 10 facing away from the lower plastic. The gap between the first pole 21, the end cap 10, and the lower plastic 50 only needs to be sealed by the first sealing ring 41. The side of the end cap assembly 100 facing away from the lower plastic can be referred to as the exterior. The end cap assembly of this embodiment does not require additional sealing between the first pressure block 61 and the first pole 21; the first sealing ring can seal both the exterior and interior of the end cap assembly. Therefore, even if the laser welding of the first pressure block 61 to the first pole 21 has welding defects such as cracks, the end cap 10 can still be used normally while ensuring other performance, reducing the defect rate and further reducing the sealing problems of the end cap assembly caused by poor welding of the first pressure block 61 to the first pole 21. Since the first pressing block 61 and the first pole 21 are connected by laser welding, the temperature generated instantaneously during welding is relatively high, and the melting point of the lower plastic 50 is lower than that of the first pressing block 61 and the first pole 21. Therefore, the temperature is very high when the first pressing block 61 and the first pole 21 are welded, which can easily cause the lower plastic 50 to melt. The first thermal insulation ring 45 is arranged between the lower plastic 50 and the first pressing block 61 and blocks the first pressing block 61 and the lower plastic 50. The heat generated during the welding of the first pressing block 61 and the first pole 21 is isolated by the first thermal insulation ring 45, thereby preventing the lower plastic 50 from melting and ensuring the safety of the end cover assembly 100.

[0085] The above are only some of the embodiments and implementations of this application. The scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. An end cap assembly for an energy storage device, characterized in that: The end cap assembly includes: end cap, pole, heat insulation ring, pressing block and lower plastic. The pole includes a pole body and a flange connected to one end of the pole body; The end cover includes 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 end cover further includes a mounting groove and a mounting hole, the mounting groove is recessed in the second surface, and the mounting hole passes through the bottom wall of the mounting groove and the first surface; The lower plastic includes a lower plastic body, and the lower plastic also includes an assembly hole, and the assembly hole passes through two surfaces of the lower plastic body in the thickness direction; The thermal insulation ring includes perforations, The end cover and the lower plastic are stacked along the thickness direction of the end cover assembly, the second surface of the end cover abuts against the lower plastic, and the assembly hole is opposite to and connected to the mounting hole; Along the thickness direction of the end cover assembly, the pole body is passed through the assembly hole and the mounting hole, the pressing block is located on the side of the lower plastic facing away from the end cover, and the pressing block is fixed to the end of the pole body away from the flange. The thermal insulation ring is sleeved on the pole body through the through-hole, and extends into the mounting hole and the assembly hole. The thermal insulation ring is blocked between the lower plastic and the pole body, and the thermal insulation ring is blocked between the end cover and the pole body. In the thickness direction of the end cover assembly, the thermal insulation ring is blocked between the pressure block and the lower plastic.

2. The end cap assembly according to claim 1, wherein: The heat-insulating ring includes a barrier body, a barrier sub-ring, and a supporting platform. The barrier sub-ring protrudes from a surface of the barrier body and forms the through hole with the barrier body. The supporting platform is protruded from the surface of the barrier body and is connected to and surrounds the barrier sub-ring. The barrier ring extends into the gap between the mounting hole and the pole body. In the thickness direction of the end cover assembly, the end cover around the mounting hole abuts against the supporting platform, the lower plastic around the assembly hole abuts against the barrier body, and the pressure block abuts against the side of the barrier body facing away from the lower plastic.

3. The end cap assembly according to claim 2, wherein: In the thickness direction of the end cover assembly, the projection of the outer contour of the pressing block overlaps with the projection of the outer contour of the barrier body, or the projection of the outer contour of the barrier body completely covers the projection of the outer contour of the pressing block.

4. The end cap assembly according to claim 1, wherein: The heat insulation ring is made of ceramic material.

5. The end cap assembly according to claim 2, wherein: The end cover assembly further includes a sealing ring, which is sleeved on the pole body and clamped between the flange and the end cover. In the thickness direction of the end cover assembly, the barrier ring abuts against the sealing ring.

6. The end cap assembly according to claim 5, wherein: The connection between the flange and the pole body is an arc-shaped surface; The sealing ring includes a sealing surface, a first connecting surface, and a second connecting surface. The first connecting surface and the second connecting surface are arranged opposite to each other along the thickness direction of the second section. The sealing surface connects the first connecting surface and the second connecting surface. The first connecting surface, the second connecting surface, and the sealing surface all face the pole body. The first connecting surface is an inclined surface and is inclined toward the pole body, or the connection between the first connecting surfaces is an arc surface. The sealing surface abuts against the circumferential surface of the pole body, the first connecting surface abuts against the arcuate surface, and the blocking sub-ring abuts against the second connecting surface and makes the second connecting surface recessed into the sealing ring.

7. The end cap assembly according to claim 4 or 5, characterized in that: The end cap assembly includes an upper plastic, the upper plastic including an upper plastic body and a flange, the upper plastic body having an inner ring surface, the flange protruding from the inner ring surface and located on one side of the upper plastic body, the upper plastic body and the flange forming a through hole; the pole body is penetrated by the through hole, the upper plastic body protrudes along the radial direction of the pole body and surrounds the outer circumference of the flange, and the flange is clamped between the flange and the end cap; The flange includes a supporting surface, which is a curved surface and abuts against a side of the sealing ring facing away from the pole body.

8. The end cap assembly according to claim 2, wherein: The surface of the lower plastic body is further provided with an avoidance groove, the avoidance hole passes through the bottom wall of the avoidance groove, the end cover further includes a mounting groove recessed in the second surface, the supporting platform is located in the mounting groove and abuts against the bottom wall of the mounting groove, the blocking body is partially located in the avoidance groove and abuts against the bottom wall of the avoidance groove.

9. An energy storage device, characterized in that: It comprises a shell, a battery cell and an end cover assembly as described in any one of claims 1 to 8, wherein the shell comprises an opening and a accommodating cavity, the battery cell is accommodated in the shell, the end cover assembly is sealed to the opening, the battery cell comprises a tab, and the tab is connected to the pole.

10. An electrical device, characterized in that: The energy storage device comprises the energy storage device as claimed in claim 9, wherein the energy storage device is used to supply power to electrical equipment.

Images