End cap assembly, energy storage device, and power supply system

Abstract

The application discloses an end cover assembly, an energy storage device and a power supply system, and relates to the technical field of energy storage. The end cover assembly comprises a cover plate, the surface of one side of the cover plate in the thickness direction is provided with a groove, the groove bottom is provided with a thinning area and a pressure relief hole penetrating through, and the thinning area is located at the periphery of the pressure relief hole; a gas permeable assembly comprises a fixed plate and a gas permeable film, the fixed plate is fixed on the groove bottom, and covers the pressure relief hole, the fixed plate is provided with a gas permeable hole penetrating through, and the gas permeable film covers the gas permeable hole; and an electrode terminal is arranged on the cover plate and has an exposed end on one side of the cover plate in the thickness direction.

Description

Technical Field

[0001] This application relates to the field of energy storage technology, and more specifically, to an end cap assembly, an energy storage device, and a power supply system. Background Technology

[0002] A rechargeable battery, also known as a secondary battery or storage battery, is a battery that can be recharged after being discharged to reactivate its active materials and continue to be used. The recyclable nature of rechargeable batteries has made them a primary power source for electrical devices. As the demand for rechargeable batteries increases, people are also placing higher demands on their performance in various aspects, especially their lifespan.

[0003] In related technologies, secondary batteries typically consist of an end cap assembly, an electrode assembly, and a housing. The actual production process involves fabricating the end cap assembly, electrode assembly, and housing separately. Then, metal adapters are used to weld the electrode posts of the end cap assembly and the tabs of the electrode assembly together. The electrode assembly is then placed inside the housing, and the end cap assembly is used to close the opening of the housing and welded shut to form the basic structure of the secondary battery. Afterward, electrolyte is manually injected through injection holes located on the end cap assembly, and these injection holes are then welded shut to seal the battery.

[0004] The end cap assembly includes a cover plate and an explosion-proof valve mounted on the cover plate. In the event of severe conditions such as thermal runaway or short circuits in the secondary battery, the explosion-proof valve will burst open due to excessive internal pressure, rapidly releasing a large amount of gas and preventing the battery from exploding. However, with advancements in battery technology, the gas production of secondary batteries (such as sodium-ion batteries) has increased during cyclic charging and discharging, causing the explosion-proof valve on the cover plate to open prematurely, thus shortening the battery's lifespan. Utility Model Content

[0005] A primary objective of this application is to provide an end cap assembly, energy storage device, and power supply system that improve exhaust reliability.

[0006] To achieve the above-mentioned objectives, this application adopts the following technical solution:

[0007] According to one aspect of this application, an end cap assembly is provided, comprising: a cover plate having a groove on one side of its thickness direction, the bottom of the groove having a thinning area and a through pressure relief hole, the thinning area being located around the pressure relief hole; a venting assembly including a fixing plate and a venting membrane, the fixing plate being fixed to the bottom of the groove and covering the pressure relief hole, the fixing plate having a through venting hole, and the venting membrane covering the venting hole; and an electrode terminal passing through the cover plate and having an end exposed on one side of the cover plate along its thickness direction.

[0008] In this embodiment, an explosion-proof valve is formed by combining the thinning area on the cover plate to ensure the explosion-proof safety of the energy storage device during thermal runaway when the end cover assembly is applied to the energy storage device. In addition, in the thickness direction of the cover plate, there is an overlapping area between the vent hole on the fixed plate and the pressure relief hole on the cover plate, so as to realize the airflow conduction on both sides of the venting component at the pressure relief hole on the cover plate. This allows the end cover assembly to normally discharge the gas inside the shell even during the cyclic charging and discharging phase when applied to the energy storage device, avoiding the premature opening of the explosion-proof valve formed by the thinning area, thereby extending the service life of the energy storage device.

[0009] According to one embodiment of this application, the wall of the pressure relief hole has a first stepped surface, the first stepped surface facing the groove opening of the groove, and the edge of the fixing plate is supported on the first stepped surface.

[0010] In this embodiment, the first step surface is provided to support the fixing plate, thereby improving the assembly efficiency of the fixing plate in the pressure relief hole; at the same time, it limits the fixing plate and ensures the stability of the fixing plate in the pressure relief hole.

[0011] According to one embodiment of this application, the wall of the pressure relief hole further has a second stepped surface; the second stepped surface is located in the area enclosed by the first stepped surface and faces the groove opening of the groove, and the edge of the breathable membrane is located between the fixing plate and the second stepped surface.

[0012] In this embodiment, the breathable membrane is limited by the second step surface, which prevents the breathable membrane from falling off the fixing plate under the impact of airflow, thereby ensuring the reliability of the fixation between the breathable membrane and the fixing plate.

[0013] According to one embodiment of this application, the breathable membrane is located within the area enclosed by the edge of the fixing plate, and the distance between the edge of the breathable membrane and the edge of the fixing plate is greater than or equal to 0.2 mm and less than or equal to 1.5 mm.

[0014] In this embodiment, the inward-shrinking design of the breathable membrane avoids the situation where the breathable membrane explodes due to heat transfer when welding the fixing plate in the groove; at the same time, it ensures the setting area of ​​the breathable membrane to ensure full coverage of the vent holes on the fixing plate.

[0015] According to one embodiment of this application, the surface of the fixing plate has an assembly groove, the vent is located at the bottom of the assembly groove, and at least a portion of the vent membrane is located within the assembly groove.

[0016] In this embodiment, the contact area between the breathable membrane and the fixing plate can be increased by setting the assembly groove, thereby ensuring the stability of the breathable membrane fixed on the fixing plate.

[0017] According to one embodiment of this application, the surface of the breathable membrane has a protrusion located within the assembly groove.

[0018] In this embodiment, for the breathable membrane with protrusions, a thickening design is implemented at the corresponding air vent positions to reduce or even avoid the breathable membrane from bulging due to airflow impact at the corresponding air vent positions.

[0019] According to one embodiment of this application, the thinning zone is annular and includes a bursting section and a connecting section, wherein the thickness of the cover plate in the bursting section is less than the thickness in the connecting section.

[0020] In this embodiment, the bursting section included in the thinning zone can be torn apart when the gas pressure inside the shell is greater than the maximum bursting pressure of the bursting section, thus ensuring the explosion-proof valve formed by the thinning zone can be opened. At the same time, based on the connecting section included in the thinning zone, the situation where the area enclosed by the thinning zone detaches from the cover plate after the bursting section tears open can be avoided, thereby ensuring safety.

[0021] According to one embodiment of this application, the bottom of the groove has an annular groove located around the pressure relief hole, and the bottom of the annular groove has the thinning area.

[0022] In this embodiment, the annular groove at the bottom of the groove facilitates the initial thinning of the area surrounding the pressure relief hole, so that etching can be performed at the bottom of the annular groove to obtain the thinned area.

[0023] According to one embodiment of this application, the groove wall has a third stepped surface facing the groove opening; the end cap assembly includes a protective sheet with a venting slit, and the edge of the protective sheet is supported on the third stepped surface.

[0024] In this embodiment, the protective sheet protects the breathable component, while the breathable seams on the protective sheet facilitate the flow of air on both sides of the protective sheet.

[0025] According to one aspect of this application, an energy storage device is provided, comprising: a housing including a receiving cavity with an opening; an electrode assembly housed within the receiving cavity; and an end cap assembly as described in the preceding aspect, the end cap assembly sealing the opening of the receiving cavity.

[0026] According to one embodiment of this application, the breathable membrane is located on the side of the fixing plate near the electrode assembly.

[0027] In this embodiment, a breathable membrane is positioned between the fixed plate and the electrode assembly. The fixed plate restricts the breathable membrane, preventing it from bulging due to high internal air pressure, thus ensuring the reliability of the breathable membrane by allowing only gas to pass through.

[0028] According to one aspect of this application, an electrical device is provided, the electrical device including the energy storage device described in the above aspect, the energy storage device supplying power to the electrical device.

[0029] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0030] The above and other features and advantages of this application will become more apparent from a detailed description of exemplary embodiments thereof with reference to the accompanying drawings.

[0031] Figure 1 This is a schematic diagram of an energy storage system according to an exemplary embodiment.

[0032] Figure 2 This is an exploded structural diagram of an energy storage device according to an exemplary embodiment.

[0033] Figure 3 This is an exploded view of an end cap assembly according to an exemplary embodiment.

[0034] Figure 4 This is a top view of an end cap assembly according to an exemplary embodiment.

[0035] Figure 5 yes Figure 4 The diagram shows a cross-sectional view of the end cap assembly along line AA.

[0036] Figure 6 yes Figure 5 The diagram shows an enlarged view of the end cap assembly in a local area.

[0037] Figure 7 Another end cap assembly is shown according to an exemplary embodiment along... Figure 4 The diagram shows a cross-sectional structure of line AA.

[0038] Figure 8 yes Figure 7 The diagram shows an enlarged view of the end cap assembly in a local area.

[0039] Figure 9 This is yet another end cap assembly shown according to an exemplary embodiment. Figure 7 The diagram shows an enlarged view of the local area.

[0040] Figure 10 This is yet another end cap assembly shown according to an exemplary embodiment. Figure 4 The diagram shows a cross-sectional structure of line AA.

[0041] Figure 11 yes Figure 10 The diagram shows an enlarged view of the end cap assembly in a local area.

[0042] Figure 12 This is a schematic diagram of the axial structure of a cover plate according to an exemplary embodiment.

[0043] Figure 13 yes Figure 12 The diagram shows an enlarged view of the cover plate in a local area.

[0044] Figure 14 This is an axial side view of an end cap assembly after the blasting section has exploded, according to an exemplary embodiment.

[0045] Figure 15 This is a schematic diagram of a power supply system according to an exemplary embodiment.

[0046] The reference numerals in the attached figures are explained as follows:

[0047] 100. Energy storage devices; 200. Power conversion devices; 300. High-voltage cables; 400. Power supply systems; 410. Electrical equipment;

[0048] 10. Housing; 20. Electrode assembly; 30. End cap assembly;

[0049] 11. Receiving cavity;

[0050] 31. Cover plate; 32. Ventilation component; 33. Electrode terminal; 34. Protective sheet; 35. First insulating component;

[0051] 311. Groove; 312. Thinning zone; 313. Pressure relief hole; 314. Injection hole;

[0052] 3111, Annular groove; 3112, Third step surface;

[0053] 3121. Blasting section; 3122. Connecting section;

[0054] 3131, First step surface; 3132, Second step surface;

[0055] 321. Fixing plate; 322. Ventilation hole; 323. Ventilation membrane; 324. Assembly slot; 325. Protrusion;

[0056] 331. Electrode post; 332. Welding ring; 333. Sealing ring; 334. Second insulating component;

[0057] 341. Ventilation seam;

[0058] 210. First conversion device; 220. Second conversion device. Detailed Implementation

[0059] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this application will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore their detailed description will be omitted.

[0060] Because the energy people need is highly time- and space-dependent, in order to make rational use of energy and improve energy efficiency, it is necessary to use a medium or device to store one form of energy in the same way or by converting it into another form of energy, and then release it in a specific form of energy based on future application needs.

[0061] Currently, the generation of green electricity generally relies on solar, wind, and hydropower. However, wind and solar power are generally characterized by strong intermittency and large fluctuations, which can cause grid instability, insufficient power during peak demand periods, and excessive power during off-peak periods. Unstable voltage can also damage the power grid. Therefore, insufficient electricity demand or insufficient grid capacity may lead to the problem of "wind and solar curtailment." Solving these problems requires energy storage. This involves converting electrical energy into other forms of energy through physical or chemical means and storing it. When needed, this energy can be converted back into electrical energy and released. Simply put, energy storage is like a large "power bank," storing electrical energy when solar and wind power are abundant and releasing the stored electricity when needed.

[0062] Taking electrochemical energy storage as an example, this solution provides an energy storage device for use in energy storage systems. The energy storage device is equipped with a set of chemical batteries, which mainly use the chemical elements in the batteries as energy storage media. The charging and discharging process is accompanied by the chemical reaction or change of the energy storage media. Simply put, the electrical energy generated by wind and solar energy is stored in the chemical batteries. When the use of external electrical energy reaches its peak, the stored electricity is released for use, or transferred to places with a shortage of electricity for use.

[0063] Current energy storage applications are quite widespread, including generation-side energy storage, grid-side energy storage, and consumption-side energy storage. The corresponding types of energy storage devices include:

[0064] (1) Large-scale energy storage power stations applied to wind power and photovoltaic power stations can assist renewable energy power generation in meeting grid connection requirements and improve the utilization rate of renewable energy. As a high-quality active / reactive power regulation power source on the power supply side, energy storage power stations can achieve load matching of power in time and space, enhance the absorption capacity of renewable energy, reduce instantaneous power changes, reduce the impact on the power grid, improve the absorption of new energy power generation, and are of great significance in power grid system backup, alleviating peak load power supply pressure and peak regulation and frequency regulation.

[0065] (2) Energy storage containers applied on the grid side mainly function as peak shaving, frequency regulation and grid congestion relief. In terms of peak shaving, they can realize peak shaving and valley filling of electricity load, that is, charging the energy storage battery when the electricity load is low and releasing the stored electricity during the peak electricity load period, thereby achieving a balance between power production and consumption.

[0066] (3) Small energy storage cabinets applied to the electricity consumption side mainly function as self-consumption of electricity, peak-valley price arbitrage, capacity cost management, and improvement of power supply reliability. Depending on the application scenario, electricity consumption side energy storage can be divided into industrial and commercial energy storage cabinets, household energy storage devices, energy storage charging piles, etc., which are generally used in conjunction with distributed photovoltaics. Industrial and commercial users can use energy storage for peak-valley price arbitrage and capacity cost management. In the electricity market implementing peak-valley pricing, by charging the energy storage system when the electricity price is low and discharging the energy storage system when the electricity price is high, peak-valley price arbitrage can be achieved, reducing electricity costs. In addition, industrial enterprises subject to two-part tariffs can use energy storage systems to store energy during off-peak hours and discharge during peak loads, thereby reducing peak power and the maximum demand declared, achieving the goal of reducing capacity charges. Household photovoltaics with energy storage can improve the level of self-consumption of electricity. Due to high electricity prices and poor power supply stability, the demand for household photovoltaic installations is driven. Given that photovoltaic power generation occurs during the day, while user load is generally higher at night, configuring energy storage can better utilize photovoltaic power, improve self-consumption levels, and reduce electricity costs. Furthermore, energy storage is needed in areas such as communication base stations and data centers for backup power.

[0067] Figure 1 This is a schematic diagram of an energy storage system provided in this application. The energy storage system is illustrated using a shared energy storage scenario on the generation / distribution side as an example. However, the energy storage device 100 of this application is not limited to a shared energy storage scenario on the generation / distribution side. Figure 1 As shown, the energy storage system includes an energy storage device 100, an energy conversion device 200, and a high-voltage cable 300.

[0068] In some embodiments of the power generation scenario, the power conversion device 200 includes a first conversion device 210 (such as a wind power conversion device). Since the electricity generated by wind power conversion is volatile, random, and intermittent, the unstable electricity output by the wind power conversion device can be stored in an energy storage device 100. The energy storage device 100 is connected to the high-voltage cable 300 and can simultaneously output smooth electricity to the distribution side for use, achieving peak shaving and frequency regulation, and ensuring stable grid operation. Alternatively, the wind power conversion device can be directly connected to the high-voltage cable 300. Under normal power generation conditions, the electricity can be converted into power through the high-voltage cable 300. The high-voltage cable 300 supplies the power generated by the wind power conversion device to the distribution side. When the current power load is low and the wind power conversion device generates excess power, the excess power is first stored in the energy storage device 100 to improve the problem of new energy power generation absorption. When the power load is high, the power grid issues an instruction to transmit the power stored in the energy storage device 100 together with the high-voltage cable 300 in grid-connected mode to supply the power to the distribution side. This provides the power grid with various services such as peak shaving, frequency regulation, and backup, giving full play to the peak shaving role of the power grid, promoting peak shaving and valley filling, and alleviating the power supply pressure of the power grid.

[0069] In some embodiments on the distribution network side, the power conversion device 200 includes a second conversion device 220 (such as a photovoltaic power conversion device), and the energy storage device 100 is connected to the photovoltaic power conversion device and installed downstream of the high-voltage cable 300 between the user load and the photovoltaic power conversion device. The electrical energy output by the photovoltaic power conversion device is stored in the energy storage device 100, which can act as a backup power source in a timely manner when the power grid / distribution network experiences a fault; or, it can alleviate line congestion on the high-voltage cable 300 transmission line and provide power supply support during power grid expansion plans to delay the economic pressure caused by power grid / distribution capacity expansion.

[0070] Optionally, the power conversion device 200 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy, and mechanical energy into electrical energy. For example, the power conversion device 200 may include, but is not limited to, photovoltaic power conversion devices, wind power conversion devices 200, etc.

[0071] Optionally, the energy storage device 100 can be used in, but is not limited to, energy storage power stations, hydropower / thermal / wind power generation systems, solar power generation systems, mobile power systems, smart home systems, or temporary power supply systems 400, and is also applied in multiple fields such as data centers, military equipment, aerospace, charging piles, and electric vehicles.

[0072] Optionally, the energy storage device 100 may include, but is not limited to, individual battery cells, as well as battery modules, battery packs, battery clusters, power banks, energy storage cabinets / containers, and other integrated battery systems composed of individual battery cells. The actual application form of the energy storage device 100 provided in this application embodiment may be, but is not limited to, the listed products, and may also be other application forms. This application embodiment does not strictly limit the application form of the energy storage device 100.

[0073] Optionally, the energy storage device 100 may include battery cells that are, but are not limited to, at least one of cylindrical, prismatic, prismatic, or other shaped batteries. The battery cells may be rechargeable batteries, meaning they can be used again after being discharged by recharging to activate the active materials. The battery cells may be lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc., and this application does not specifically limit their types.

[0074] In some implementations, such as Figure 2 As shown, the energy storage device 100 includes: a housing 10, an electrode assembly 20, and an end cap assembly 30. The housing 10 has an open receiving cavity 11, the electrode assembly 20 is housed in the receiving cavity 11, and the end cap assembly 30 seals the opening of the receiving cavity 11.

[0075] The housing 10 can be a cylindrical structure with one end open. In this case, the energy storage device 100 includes an end cap assembly 30 to seal one opening of the housing 10. Alternatively, the housing 10 can be a cylindrical structure with both ends open. In this case, the energy storage device 100 includes an end cap assembly 30 and a cover plate 31, or two end cap assemblies 30, to seal the two openings of the housing 10 respectively through one end cap assembly 30 and a cover plate 31, or two end cap assemblies 30.

[0076] Among them, such as Figure 3 As shown, the end cap assembly 30 includes a cover plate 31 and an electrode terminal 33. The electrode terminal 33 passes through the cover plate 31, with one end connected to the electrode assembly 20 and the other end exposed to serve as an output terminal of the energy storage device 100; secondly, as Figure 3 As shown, the cover plate 31 is provided with a liquid injection hole 314 to facilitate the injection of electrolyte into the receiving cavity 11 through the liquid injection hole 314 after the basic assembly of the energy storage device 100 is completed, thereby achieving the wetting of the electrode assembly 20; finally, as shown Figure 3 As shown, a first insulating member 35 is also provided on the side of the cover plate 31 facing the electrode assembly 20. The electrode terminal 33 passes through the first insulating member 35 and the cover plate 31 to ensure electrical insulation between the electrode terminal 33 and the cover plate 31, as well as electrical insulation between the electrode assembly 20 and the cover plate 31.

[0077] Optionally, such as Figure 3 As shown, the electrode terminal 33 includes an electrode post 331, a welding ring 332, a sealing ring 333, and a second insulating member 334. The electrode post 331 passes through the cover plate 31, with its first end exposed on a first side of the cover plate 31 along its thickness direction. The second insulating member 334 is sandwiched between the first end of the electrode post 331 and the cover plate 31 to ensure electrical insulation between the electrode post 331 and the cover plate 31. The welding ring 332 is located on a second side of the cover plate 31 along its thickness direction and is sleeved and fixed to the second end of the electrode post 331. The sealing ring 333 is sandwiched between the welding ring 332 and the cover plate 31 to ensure the sealing of the electrode post 331 assembly. In this case, the second end of the electrode post 331 can be electrically connected to the electrode assembly 20, and the first end can realize the output of electrical energy from the electrode assembly 20.

[0078] The electrode assembly 20 includes a first electrode, a second electrode, and a diaphragm stacked together. The first and second electrodes have opposite polarities, and the diaphragm is located between the first and second electrodes. The electrode assembly 20 has a first tab connected to the first electrode and a second tab connected to the second electrode at its end. The first and second tabs can be located at the same end or at different ends of the electrode assembly 20. Taking the first and second tabs located at the same end of the electrode assembly 20 as an example, the end cap assembly 30 includes two electrode terminals 33 passing through a cover plate 31. The first and second tabs are respectively connected to the two electrode terminals 33 to achieve the output of electrical energy from the electrode assembly 20 through the two electrode terminals 33.

[0079] It should be noted that the energy storage device 100 also includes a metal adapter to connect the tabs of the electrode assembly 20 to the electrode terminals 33 on the end cap assembly 30, thereby ensuring the overcurrent capacity between the electrode terminals 33 and the electrode assembly 20.

[0080] Figure 4 A top view of an end cap assembly 30 provided in an embodiment of this application is illustrated. Figure 5 Example Figure 4 The diagram shown is an exploded cross-sectional view of the end cap assembly 30. Figure 6 Example Figure 5 A partially enlarged structural schematic diagram of the end cap assembly 30 shown.

[0081] like Figure 4 , Figure 5 and Figure 6As shown, the end cap assembly 30 includes: a cover plate 31, a venting assembly 32, and an electrode terminal 33. The cover plate 31 has a groove 311 on one side of its thickness direction. The bottom of the groove 311 has a thinning area 312 and a through pressure relief hole 313. The thinning area 312 is located around the pressure relief hole 313. The venting assembly 32 includes a fixing plate 321 and a venting membrane 323. The fixing plate 321 is fixed to the bottom of the groove 311 and covers the pressure relief hole 313. The fixing plate 321 has a through venting hole 322, and the venting membrane 323 covers the venting hole 322. The electrode terminal 33 is inserted through the cover plate 31 and has an end exposed on one side of the cover plate 31 along its thickness direction.

[0082] Thus, the explosion-proof valve is formed by the thinning area 312 on the cover plate 31, ensuring the explosion-proof safety of the energy storage device 100 during thermal runaway when the end cover assembly 30 is applied to the energy storage device 100. In addition, in the thickness direction of the cover plate 31, the vent hole 322 on the fixing plate 321 and the pressure relief hole 313 on the cover plate 31 overlap, so as to realize the airflow conduction on both sides of the venting assembly 32 at the pressure relief hole 313 on the cover plate 31. This allows the end cover assembly 30 to normally discharge the gas inside the housing 10 even during the cyclic charging and discharging stage when it is applied to the energy storage device 100, avoiding the premature opening of the explosion-proof valve formed by the thinning area 312, thereby extending the service life of the energy storage device 100.

[0083] Specifically, when the end cap assembly 30 seals the opening of the housing 10, the groove 311 on the cover plate 31 can face the electrode assembly 20, or the groove 311 on the cover plate 31 can face away from the electrode assembly 20. Furthermore, the venting assembly 32 included in the end cap assembly 30 can have a venting membrane 323 located on the side of the fixing plate 321 away from the electrode assembly 20, or the venting membrane 323 located on the side of the fixing plate 321 closer to the electrode assembly 20. When the venting membrane 323 is located between the fixing plate 321 and the electrode assembly 20, the restriction imposed by the fixing plate 321 on the venting membrane 323 prevents it from inflating due to high air pressure inside the housing 10, thus ensuring the reliability of the venting membrane 323 in allowing only gas to pass through.

[0084] In this embodiment, the groove 311 on the cover plate 31 can be located at the center of the cover plate 31. Correspondingly, the ventilating component 32 is disposed at the center of the groove 311 of the cover plate 31 to ensure the symmetry of the path of the gas in the housing 10 when it is discharged along the ventilating membrane 323. This avoids the ventilating component 32 from becoming loose or displaced due to airflow impact in the groove 311, and ensures the reliability of the ventilating component 32 being fixed in the groove 311.

[0085] The fixing plate 321 included in the ventilated component 32 can be made of the same material as the cover plate 31 to ensure the reliability of the fixing plate 321's welding and fixing to the bottom of the groove 311. For example, both the fixing plate 321 and the cover plate 31 are made of 3003 aluminum alloy, 304 stainless steel, etc. The ventilated membrane 323 included in the ventilated component 32 is a thin film made of polymer material, allowing only gas to pass through. The ventilated membrane 323 can be fixedly connected to the fixing plate 321 by adhesive or other means.

[0086] Additionally, the vent 322 on the fixing plate 321 can be a large-sized vent 322, or it can be as follows: Figure 4 The multiple small-sized vent holes 322 are shown. When the fixing plate 321 has multiple small-sized vent holes 322, it is convenient for the fixing plate 321 to limit the breathable membrane 323 and avoid the deformation of the breathable membrane 323 at the vent holes 322.

[0087] Among them, the breathable membrane 323 included in the breathable component 32 can be as follows: Figure 5 and Figure 6 As shown, the breathable membrane 323 is directly fixed to the surface of the fixing plate 321. For example, when the breathable membrane 323 covers the air holes 322 on the fixing plate 321, the breathable membrane 323 is bonded and fixed to the outside of the air holes 322 with an adhesive to ensure the breathability of the breathable membrane 323 at the air holes 322.

[0088] Of course, it can also be like this Figure 7 and Figure 8 As shown, the surface of the fixing plate 321 has a mounting groove 324, and the vent hole 322 is located at the bottom of the mounting groove 324. At least a portion of the breathable membrane 323 is located within the mounting groove 324. In this way, the contact area between the breathable membrane 323 and the fixing plate 321 can be increased by the mounting groove 324, thereby ensuring the stability of the breathable membrane 323 fixed on the fixing plate 321.

[0089] This could mean that the entire breathable membrane 323 is embedded in the mounting groove 324 on the fixing plate 321, or it could be like... Figure 8 As shown, the surface of the breathable membrane 323 has a protrusion 325, which is located in the mounting groove 324 on the fixing plate 321.

[0090] When the entire breathable membrane 323 is embedded in the assembly groove 324, the breathable membrane 323 can be fixed in the manner described above. That is, the breathable membrane 323 is bonded and fixed to the bottom of the assembly groove 324 and around the vent holes 322 using an adhesive. When the protrusions 325 on the breathable membrane 323 are embedded in the assembly groove 324, the area around the protrusions 325 on the breathable membrane 323 can be bonded and fixed to the fixing plate 321 using an adhesive. In addition, for the breathable membrane 323 with protrusions 325, a thickened design is implemented at the position corresponding to the vent holes 322, thereby reducing or even avoiding the bulging of the breathable membrane 323 at the position corresponding to the vent holes 322 due to airflow impact.

[0091] Specifically, the breathable membrane 323 fixed on the fixing plate 321 can be located within the area enclosed by the edge of the fixing plate 321, and as shown in the example below. Figure 6 or Figure 8 As shown, the distance L between the edge of the breathable membrane 323 and the edge of the fixing plate 321 is greater than or equal to 0.2 mm and less than or equal to 1.5 mm.

[0092] Thus, based on the inward-recessed design of the breathable membrane 323, the possibility of the breathable membrane 323 exploding due to heat transfer during the welding of the fixing plate 321 within the groove 311 is avoided; at the same time, the area of ​​the breathable membrane 323 is ensured to fully cover the vent holes 322 on the fixing plate 321. For example, the distance L between the edge of the breathable membrane 323 and the edge of the fixing plate 321 is 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm, 1.0 mm, 1.2 mm, 1.4 mm, 1.5 mm, etc. Of course, the distance between the edge of the breathable membrane 323 and the edge of the fixing plate 321 can also be slightly less than 0.2 mm or slightly greater than 1.5 mm, as long as it ensures full coverage of the vent holes 322 on the fixing plate 321 and avoids the occurrence of exploding points on the fixing plate 321 during welding.

[0093] In this embodiment of the application, when the fixing plate 321 is fixed in the groove 311, the fixing plate 321 may cover the pressure relief hole 313 and be fixedly connected to the bottom of the groove 311 (e.g., by welding); or the fixing plate 321 may be embedded in the pressure relief hole 313 and be fixedly connected to the hole wall or the edge of the opening of the pressure relief hole 313 (e.g., by welding).

[0094] When the fixing plate 321 is embedded in the pressure relief hole 313 for fixation, the limitation on the depth of the groove 311 on the cover plate 31 is avoided, thus facilitating the thinning design of the cover plate 31. Additionally, as... Figure 6 or Figure 8As shown, the thickness H1 of the cover plate 31 at the bottom of the groove 311 is greater than or equal to 0.5 mm and less than or equal to 1.8 mm, that is, the depth of the pressure relief hole 313 on the cover plate 31 is greater than or equal to 0.5 mm and less than or equal to 1.8 mm, to ensure the assembly of the ventilated component 32 within the pressure relief hole 313. For example, the thickness H1 of the cover plate 31 at the bottom of the groove 311 is 0.5 mm, 0.8 mm, 1 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, etc.

[0095] In some implementations, such as Figure 6 or Figure 8 As shown, the wall of the pressure relief hole 313 has a first stepped surface 3131, which faces the groove of the groove 311, and the edge of the fixing plate 321 is supported on the first stepped surface 3131.

[0096] Thus, by setting the first step surface 3131, the fixing plate 321 is supported, thereby improving the assembly efficiency of the fixing plate 321 in the pressure relief hole 313; at the same time, the fixing plate 321 is limited, ensuring the stability of the fixing plate 321 in the pressure relief hole 313.

[0097] The thickness H2 of the cover plate 31 at the first step surface 3131 is greater than or equal to 0.5 mm and less than or equal to 1.8 mm. This avoids burn-through during welding of the fixing plate 321 while ensuring the thinning design of the cover plate 31. For example, the thickness H2 of the cover plate 31 at the first step surface 3131 is 0.5 mm, 0.7 mm, 1.0 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, etc.

[0098] In some implementations, such as Figure 9 As shown, the wall of the pressure relief hole 313 also has a second stepped surface 3132; the second stepped surface 3132 is located in the area enclosed by the first stepped surface 3131 and faces the groove of the groove 311, and the edge of the breathable membrane 323 is located between the fixing plate 321 and the second stepped surface 3132.

[0099] In this way, the breathable membrane 323 can be limited by the second step surface 3132, which prevents the breathable membrane 323 from falling off the fixing plate 321 under the impact of airflow, thereby ensuring the reliability of the fixation between the breathable membrane 323 and the fixing plate 321.

[0100] In conjunction with the above description, when the groove 311 on the cover plate 31 faces away from the electrode assembly 20, the breathable membrane 323 is located on the side of the fixing plate 321 close to the electrode assembly 20. Thus, under the limitation of the fixing plate 321, the breathable membrane 323 can be prevented from bulging due to airflow impact.

[0101] In some implementations, such as 3, Figure 10 and Figure 11 As shown, the groove wall of the groove 311 has a third stepped surface 3112 facing the groove opening; the end cap assembly 30 includes a protective sheet 34 with a vent slit 341, and the edge of the protective sheet 34 is supported on the third stepped surface 3112.

[0102] Thus, the protective sheet 34 protects the breathable component 32, while the breathable seam 341 on the protective sheet 34 facilitates the flow of air on both sides of the protective sheet 34.

[0103] The ventilation seam 341 on the protective sheet 34 can be one or more straight seams, curved seams, etc., or it can be like... Figure 3 The cross-shaped seams shown are sufficient to ensure airflow on both sides of the protective sheet 34. Additionally, as... Figure 11 As shown, the step depth H3 corresponding to the third step surface 3112 is greater than or equal to 0.15 mm and less than or equal to 0.3 mm. For example, the step depth H3 corresponding to the third step surface 3112 is 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, etc.

[0104] In some implementations, such as Figure 4 , Figure 12 and Figure 13 As shown, the thinning zone 312 is annular and includes a blasting section 3121 and a connecting section 3122. The thickness of the cover plate 31 in the blasting section 3121 is less than the thickness in the connecting section 3122.

[0105] Thus, the bursting section 3121 included in the thinning zone 312 can be torn when the gas pressure inside the shell 10 is greater than the maximum bursting pressure of the bursting section 3121, ensuring the explosion-proof valve formed by the thinning zone 312 can be opened. At the same time, based on the connecting section 3122 included in the thinning zone 312, the situation where the area enclosed by the thinning zone 312 detaches from the cover plate 31 after the bursting section 3121 is torn open can be avoided, thereby ensuring safety.

[0106] Among them, the thinning zone 312 includes the blasting section 3121 after blasting, as follows Figure 14As shown. In addition, the thickness of the cover plate 31 in the blasting section 3121 is greater than or equal to 0.05 mm and less than or equal to 0.2 mm, and the thickness of the cover plate 31 in the connecting section 3122 is greater than or equal to 0.15 mm and less than or equal to 0.4 mm. For example, the thickness of the cover plate 31 may be 0.05 mm in the blasting section 3121 and 0.15 mm in the connecting section 3122; or the thickness may be 0.08 mm in the blasting section 3121 and 0.2 mm in the connecting section 3122; or the thickness may be 0.1 mm in the blasting section 3121 and 0.24 mm in the connecting section 3122; or the thickness may be 0.14 mm in the blasting section 3121 and 0.28 mm in the connecting section 3122; or the thickness may be 0.16 mm in the blasting section 3121 and 0.34 mm in the connecting section 3122; or the thickness may be 0.2 mm in the blasting section 3121 and 0.4 mm in the connecting section 3122, etc.

[0107] It should be noted that the thinning zone 312 surrounding the pressure relief hole 313 may include not only the bursting section 3121 and the connecting section 3122 mentioned above, but may also include only the bursting section 3121 mentioned above, as long as it can ensure that at least part of the thinning zone 312 bursts open when the gas pressure inside the shell 10 is high.

[0108] In some implementations, such as Figure 11 and 13 As shown, the bottom of the groove 311 has an annular groove 3111 located around the pressure relief hole 313, and the bottom of the annular groove 3111 has a thinning area 312.

[0109] Thus, the annular groove 3111 provided at the bottom of the groove 311 facilitates the initial thinning treatment of the area surrounding the pressure relief hole 313, so that etching can be performed at the bottom of the annular groove 3111 to obtain the thinned area 312.

[0110] Its existence is like Figure 11 As shown, the thickness H4 of the cover plate 31 at the annular groove 3111 is greater than or equal to 0.25 mm and less than or equal to 0.5 mm. For example, the thickness H4 of the cover plate 31 within the annular groove 3111 is 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, etc.

[0111] Furthermore, the distance between the thinning zone 312 and the wall of the annular groove 3111 can be greater than or equal to 0.3 mm and less than or equal to 1.5 mm to ensure the uniformity of the thickness of the thinning zone 312 when it is made at the bottom of the annular groove 3111, thereby ensuring the stability of the thinning zone 312 during explosion. For example, the distance between the thinning zone 312 and the wall of the annular groove 3111 can be 0.3 mm, 0.5 mm, 0.8 mm, 1 mm, 1.2 mm, 1.5 mm, etc.

[0112] This application also provides a power supply system 400, such as... Figure 15 As shown, the power supply system 400 includes: electrical equipment 410 and the energy storage device 100 described in the above embodiments, the energy storage device 100 being used to supply power to the electrical equipment 410.

[0113] The electrical device 410 is electrically connected to the energy storage device 100. Thus, in conjunction with the above description, the power supply system 400 of this application ensures the reliability of the power supply from the energy storage device 100 to the electrical device 410 during use, based on the stable exhaust effect of the energy storage device 100.

[0114] In the embodiments of this application, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "install," "connect," "link," and "fix" should be interpreted broadly. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "link" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application based on the specific circumstances.

[0115] In the description of the embodiments of this application, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0116] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the implementation of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0117] The above are merely preferred embodiments of the implementation methods of this application and are not intended to limit the implementation methods of this application. For those skilled in the art, various modifications and variations can be made to the implementation methods of this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the implementation methods of this application should be included within the protection scope of the implementation methods of this application.

Claims

1. An end cap assembly, characterized in that, include: Cover plate (31), the cover plate (31) has a groove (311) on one side of the surface in the thickness direction, the bottom of the groove (311) has a thinning area (312) and a through pressure relief hole (313), the thinning area (312) is located around the pressure relief hole (313); A breathable component (32) includes a fixing plate (321) and a breathable membrane (323). The fixing plate (321) is fixed to the bottom of the groove (311) and covers the pressure relief hole (313). The fixing plate (321) has a through breathable hole (322), and the breathable membrane (323) covers the breathable hole (322). Electrode terminals (33) are inserted through the cover plate (31) and have an end exposed on one side of the cover plate (31) along the thickness direction.

2. The end cap assembly as claimed in claim 1, characterized in that, The pressure relief hole (313) has a first stepped surface (3131) on its wall, which faces the opening of the groove (311), and the edge of the fixing plate (321) is supported on the first stepped surface (3131).

3. The end cap assembly as described in claim 2, characterized in that, The wall of the pressure relief hole (313) also has a second stepped surface (3132); The second step surface (3132) is located in the area enclosed by the first step surface (3131) and faces the opening of the groove (311). The edge of the breathable membrane (323) is located between the fixing plate (321) and the second step surface (3132).

4. The end cap assembly as claimed in claim 1, characterized in that, The breathable membrane (323) is located within the area enclosed by the edge of the fixing plate (321), and the distance between the edge of the breathable membrane (323) and the edge of the fixing plate (321) is greater than or equal to 0.2 mm and less than or equal to 1.5 mm.

5. The end cap assembly as claimed in claim 1, characterized in that, The surface of the fixing plate (321) has an assembly groove (324), the vent hole (322) is located at the bottom of the assembly groove (324), and at least a portion of the vent membrane (323) is located within the assembly groove (324).

6. The end cap assembly as claimed in claim 5, characterized in that, The surface of the breathable membrane (323) has a protrusion (325) located in the assembly groove (324).

7. The end cap assembly as claimed in claim 1, characterized in that, The thinning zone (312) is annular and includes a bursting section (3121) and a connecting section (3122), wherein the thickness of the cover plate (31) in the bursting section (3121) is less than the thickness in the connecting section (3122).

8. The end cap assembly as described in any one of claims 1-7, characterized in that, The bottom of the groove (311) has an annular groove (3111) located around the pressure relief hole (313), and the bottom of the annular groove (3111) has the thinning area (312).

9. The end cap assembly as described in any one of claims 1-7, characterized in that, The groove (311) has a third stepped surface (3112) facing the groove opening; The end cap assembly (30) includes a protective sheet (34) having a vent slit (341) and the edge of the protective sheet (34) being supported on the third step surface (3112).

10. An energy storage device, characterized in that, include: The housing (10) includes a receiving cavity (11) with an opening; Electrode assembly (20) is housed within the receiving cavity (11); The end cap assembly (30) according to any one of claims 1-9, wherein the end cap assembly (30) seals the opening of the receiving cavity (11).

11. The energy storage device as described in claim 10, characterized in that, The breathable membrane (323) is located on the side of the fixing plate (321) near the electrode assembly (20).

12. A power supply system, characterized in that, The power supply system (400) includes electrical equipment (410) and energy storage device (100) as described in claim 10 or 11, wherein the energy storage device (100) supplies power to the electrical equipment (410).

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