Energy storage device and electric device

Abstract

The application relates to an energy storage device and an electric equipment. The energy storage device comprises a shell and a cover assembly. The shell has a receiving cavity. The cover assembly seals the receiving cavity and comprises a cover piece, a lower sealing piece and a one-way valve assembly. The cover piece and the lower sealing piece are located on the same side of the shell. The shell, the lower sealing piece and the cover piece are sequentially arranged. The cover piece has a mounting groove, an exhaust hole, a first surface and a second surface. The second surface is arranged to face the receiving cavity. The mounting groove is recessed in the first surface. The air inlet hole penetrates the second surface and the bottom wall of the mounting groove. The lower sealing piece has a through hole. The through hole is respectively connected with the receiving cavity, the air inlet hole and the mounting groove. The one-way valve assembly comprises a one-way valve subassembly and a first interface piece. The one-way valve subassembly is installed in the mounting groove. The one-way valve subassembly is used for making the fluid flow from the second surface side to the first surface side. The first interface piece is arranged on the first surface side of the cover piece and is connected with the one-way valve subassembly. The first interface piece is used for connecting an external collecting pipeline.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to an energy storage device and an electrical appliance. Background Technology

[0002] In the field of battery technology, the recyclable nature of rechargeable batteries has gradually made them a major power source for electrical devices. As the demand for rechargeable batteries increases, higher requirements are being placed on their energy density, reliability, and cost. Current batteries produce a large amount of gas, leading to an increase in internal pressure. This gas is then released through explosion-proof valves or one-way valves. The main components of this gas are flammable and explosive gases such as hydrogen and carbon monoxide. When these gases are released from the battery and accumulate around it, they can easily cause fires and explosions, reducing the battery's safety performance. Utility Model Content

[0003] In view of this, this application provides an energy storage device and an electrical device, wherein the end cap assembly can collect fluid flowing to the first surface side, and the energy storage device has high safety performance.

[0004] This application provides an energy storage device, comprising: a housing and an end cap assembly; the housing having a receiving cavity; the end cap assembly for sealing the receiving cavity, the end cap assembly comprising: an end cap member, a lower seal member, and a one-way valve assembly; the end cap member and the lower seal member being located on the same side of the housing, and the housing, the lower seal member, and the end cap member being arranged sequentially; the end cap member having a mounting groove, an air inlet, a first surface and a second surface disposed opposite to each other along the thickness direction of the end cap member, the second surface facing the receiving cavity, the mounting groove being recessed in the first surface, and the air inlet... The hole penetrates the second surface and the bottom wall of the mounting groove; the lower seal has a through hole that penetrates two opposing surfaces of the lower seal along its thickness direction, and the through hole connects the receiving cavity, the air inlet, and the mounting groove respectively; the one-way valve assembly includes a one-way valve sub-assembly and a first interface component, the one-way valve sub-assembly is installed in the mounting groove, and the one-way valve sub-assembly is used to allow fluid to flow from the second surface side to the first surface side; the first interface component is located on the first surface side of the end cap and connects to the one-way valve sub-assembly, and the first interface component is used to connect to an external collection pipe.

[0005] Furthermore, the end cap also has a first groove that penetrates the first surface and surrounds the outer periphery of the one-way valve subassembly. The first interface includes a first flange and a first interface portion connected together. The first flange is disposed in the first groove and is fixedly connected to the side wall of the first groove. Along the thickness direction of the end cap, the depth of the first groove is h1 and the thickness of the first flange is h2. Then the end cap assembly satisfies the relationship: h1-h2≥0.3mm.

[0006] Furthermore, if the thickness of the end cap is h3 along the thickness direction of the end cap, then the end cap assembly satisfies the relationship: 0.2×h3≤h1≤0.8×h3.

[0007] Furthermore, the first interface component satisfies one of the following conditions: the outer periphery of the first interface portion is provided with an external thread so that the first interface portion is threadedly connected to the external collection pipe; the inner side of the first interface portion is provided with an internal thread so that the first interface portion is threadedly connected to the external collection pipe.

[0008] Furthermore, the outer periphery of the first interface part is provided with an external thread, the inner diameter of the first interface part is D1, and the outer diameter of the first interface part is D2. Then the first interface part satisfies the relationship: D2-D1≥0.8×h2.

[0009] Furthermore, if the height of the first interface portion is h4 along the thickness direction of the end cap, then the end cap assembly satisfies the relationship: 0.5×D2≤h4≤1.5×D2.

[0010] Furthermore, the one-way valve subassembly includes a sealing ring, a sealing sheet, a spring sheet, and a welding sheet. Along the thickness direction of the end cap, the sealing ring, the sealing sheet, the spring sheet, and the welding sheet are sequentially disposed in the mounting groove; the first interface component is connected to the welding sheet.

[0011] Furthermore, the mounting groove includes a first sub-groove and a second sub-groove that are connected to each other. The first sub-groove and the second sub-groove are coaxially arranged. The first sub-groove is recessed in the first surface. The air inlet hole penetrates the bottom wall of the second sub-groove. The radial dimension of the first sub-groove is greater than that of the second sub-groove. The sealing ring and the sealing sheet are located in the second sub-groove. The spring is engaged with the welding sheet. The welding sheet and the first interface piece are located in the first sub-groove.

[0012] Furthermore, the welding piece has a snap-fit ​​hole; the spring sheet includes an elastic part, a through part, and a mating part that are bent and connected in sequence. The elastic part and the mating part are bent toward the same side relative to the through part. The through part passes through the snap-fit ​​hole. The elastic part is located on the side of the welding piece facing the sealing sheet. The elastic part has a vent hole that penetrates two opposing surfaces of the elastic part along the thickness direction. The mating part is located on the side of the welding piece away from the sealing sheet.

[0013] Furthermore, if the inner diameter of the first interface portion is D1, and the maximum radial dimension of the mating portion is D3 along the radial direction of the mating portion, then the end cap assembly satisfies the relationship: 2mm≤D1-D3≤6mm.

[0014] Furthermore, if the inner diameter of the through part is D4 and the thickness of the spring piece is T, then the end cap assembly satisfies the relationship: 5T≤D3-D4≤10T.

[0015] Furthermore, the end cap also has an explosion-proof hole that penetrates the first surface and the second surface; the end cap assembly further includes an explosion-proof valve assembly, which includes an explosion-proof valve sub-assembly and a second interface component. The explosion-proof valve sub-assembly is mounted on the end cap and covers the explosion-proof hole; the second interface component is located on the first surface side and communicates with the explosion-proof valve sub-assembly, and is used to connect to an external collection pipe.

[0016] Furthermore, along the length direction of the end cap, the width of the explosion-proof valve sub-assembly is W1, and the inner diameter of the second interface component is W2. Then, the end cap assembly satisfies the relationship: W2≥2×(W1+3mm).

[0017] Furthermore, the end cap has a second groove that penetrates the first surface and surrounds the outer periphery of the explosion-proof valve subassembly; the second interface includes a connected second flange and a second interface, the second flange surrounds the outer periphery of the second interface and is disposed in the second groove, and the second interface is used to connect to an external collection pipe; along the thickness direction of the end cap, the height of the second interface is W3, then the end cap assembly satisfies the relationship: W3≥W1+3mm.

[0018] Furthermore, the outer periphery of the second interface portion is provided with a protruding structure.

[0019] Furthermore, the end cap has a second groove that penetrates the first surface and surrounds the outer periphery of the explosion-proof valve subassembly; the second interface includes a connected second flange, a connecting portion, and a second interface portion, the second flange surrounds the outer periphery of the connecting portion, the second flange is disposed in the second groove, and the second interface portion is used to connect to an external collection pipe.

[0020] Furthermore, the connecting portion includes a first connecting sub-portion and a second connecting sub-portion connected together. The end of the first connecting sub-portion facing away from the second connecting sub-portion is connected to the second flange portion, and the end of the second connecting sub-portion facing away from the first connecting sub-portion is connected to the second interface portion. Both the first connecting sub-portion and the second interface portion extend along the thickness direction of the end cap, and the radial dimension of the first connecting sub-portion is greater than the radial dimension of the second interface portion.

[0021] Furthermore, if the height of the first connecting part is W4 along the thickness direction of the end cap, then the end cap assembly satisfies the relationship: W4≥W1+4mm.

[0022] This application provides an electrical device, which includes: a device body and an energy storage device provided in this application, wherein the energy storage device supplies power to the device body.

[0023] In the end cap assembly provided in this application, the first interface is disposed on the first surface side of the end cap and communicates with the one-way valve subassembly. This allows the first interface to be directly connected to an external collection pipe when the one-way valve subassembly is opened and fluid flows from the second surface side to the first surface side. This collects the fluid delivered to the first surface side, preventing flammable and explosive gases in the fluid from accumulating on the first surface side and directly igniting and exploding, thus improving the safety performance of the end cap assembly. Specifically, in the energy storage device, a large amount of flammable and explosive gases may be generated in the storage cavity of the energy storage device due to overcharging, short circuits, or extreme conditions such as high temperatures. The one-way valve subassembly can be used to allow fluid to flow from the side of the end cap facing the electrode assembly to the side of the end cap away from the electrode assembly, balancing the pressure on the first and second surface sides, and balancing the internal and external air pressure of the energy storage device. This prevents the energy storage device from bulging, ruptured, or even exploding, thus improving the safety performance of the energy storage device. Furthermore, the first interface is connected to an external collection pipe to collect and process the gas discharged from the energy storage device, thereby preventing flammable and explosive gases in the fluid from igniting and exploding directly on the surface of the energy storage device, and further improving the safety performance of the energy storage device. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the implementation will be briefly introduced below. Obviously, the drawings described below are some implementations of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of an energy storage system according to an embodiment of this application;

[0026] Figure 2 This is a schematic diagram of the structure of an energy storage system according to another embodiment of this application;

[0027] Figure 3 This is a schematic diagram of the structure of an energy storage system according to another embodiment of this application;

[0028] Figure 4 This is a schematic diagram of the end cap assembly according to the first embodiment of this application;

[0029] Figure 5 This is a partial exploded view of the end cap assembly according to the first embodiment of this application. Figure 1 ;

[0030] Figure 6 This is a schematic diagram of the structure of an energy storage device according to an embodiment of this application;

[0031] Figure 7 This is a partial exploded view of the end cap assembly according to the first embodiment of this application. Figure 2 ;

[0032] Figure 8 This is a top view of the end cap assembly according to the first embodiment of this application;

[0033] Figure 9 for Figure 8 Schematic diagram of the cross-sectional structure along the AA direction;

[0034] Figure 10 for Figure 9 Enlarged view of the dashed box in section B;

[0035] Figure 11 This is an exploded structural diagram of a one-way valve subassembly according to an embodiment of this application;

[0036] Figure 12 This is a schematic diagram of the end cap assembly according to the second embodiment of this application;

[0037] Figure 13 This is a top view of the end cap assembly according to the second embodiment of this application;

[0038] Figure 14 for Figure 13A schematic diagram of the cross-sectional structure along the CC direction;

[0039] Figure 15 This is a schematic diagram of the end cap assembly according to the third embodiment of this application;

[0040] Figure 16 This is a top view of the end cap assembly according to the third embodiment of this application;

[0041] Figure 17 for Figure 16 Schematic diagram of the cross-sectional structure in the DD direction;

[0042] Figure 18 for Figure 17 Enlarged view within the dashed box in the middle E;

[0043] Figure 19 This is a partial structural schematic diagram of the one-way valve subassembly according to the third embodiment of this application;

[0044] Figure 20 This is a schematic diagram of the end cap assembly according to the fourth embodiment of this application;

[0045] Figure 21 This is an exploded view of the end cap assembly according to the fourth embodiment of this application. Figure 1 ;

[0046] Figure 22 This is an exploded view of the end cap assembly according to the fourth embodiment of this application. Figure 2 ;

[0047] Figure 23 This is a top view of the end cap assembly according to the fourth embodiment of this application;

[0048] Figure 24 for Figure 23 Schematic diagram of the cross-sectional structure in the FF direction;

[0049] Figure 25 This is a schematic diagram of the end cap assembly according to the fifth embodiment of this application;

[0050] Figure 26 This is an exploded view of the end cap assembly according to the fifth embodiment of this application;

[0051] Figure 27 This is a top view of the end cap assembly according to the fifth embodiment of this application;

[0052] Figure 28 for Figure 27 Schematic diagram of the cross-sectional structure in the GG direction;

[0053] Figure 29 This is a circuit block diagram of an electrical device according to an embodiment of this application;

[0054] Figure 30 This is a schematic diagram of the structure of an electrical device according to an embodiment of this application.

[0055] Explanation of reference numerals in the attached figures:

[0056] 100 - End cap assembly, 110 - End cap piece, 111 - Mounting groove, 1111 - First sub-groove, 1112 - Second sub-groove, 112 - First surface, 113 - Second surface, 114 - First groove, 115 - Explosion-proof hole, 116 - Second groove, 117 - Air inlet, 120 - One-way valve assembly, 130 - One-way valve sub-assembly, 131 - Sealing ring, 132 - Sealing plate, 133 - Spring, 1331 - Elastic part, 1332 - Through part, 1333 - Mating part, 1334 - Exhaust hole, 134 - Welding piece, 1341 - Snap-fit ​​hole, 140 - First interface piece, 141 - First flange part, 142 - First interface part, 143 - First channel, 150 - Explosion-proof valve assembly, 160 - Explosion-proof valve sub-assembly 170-Second interface component, 171-Second flange, 172-Second interface component, 1721-Protruding structure, 1722-First sub-component, 1723-Second sub-component, 173-Connecting part, 1731-First connecting sub-component, 1732-Second connecting sub-component, 174-Second channel, 180-Lower seal, 181-Through hole, 200-Energy storage device, 210-Housing shell, 211-Receiving cavity, 220-Electrode assembly, 300-Electrical equipment, 310-Equipment body, 400-Energy storage system, 410-First power conversion device, 420-First user load, 430-Second user load, 440-High voltage cable, 450-Second power conversion device, 460-Photovoltaic energy storage charging station, 470-Automobile. Detailed Implementation

[0057] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0058] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0059] In this document, references to "embodiment" or "implementation" mean that a particular feature, structure, or characteristic described in connection with an embodiment or implementation may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0060] In the field of battery technology, the recyclable nature of rechargeable batteries has gradually made them a major power source for electrical devices. As the demand for rechargeable batteries increases, higher requirements are being placed on their energy density, reliability, and cost. Current batteries produce a large amount of gas, leading to an increase in internal pressure. This gas is then released through explosion-proof valves or one-way valves. The main components of this gas are flammable and explosive gases such as hydrogen and carbon monoxide. When these gases are released from the battery and accumulate around it, they can easily cause fires and explosions, reducing the battery's safety performance.

[0061] Understandably, a rechargeable battery, also known as a rechargeable battery or storage battery, is a battery that can be recharged after being discharged to activate its active materials and continue to be used.

[0062] Understandably, the battery may generate a large amount of gas when it is overcharged, short-circuited, or exposed to high temperatures. This gas is discharged through an explosion-proof valve or a one-way valve to prevent the battery from bulging, rupturing, or even exploding due to a sudden increase in internal pressure.

[0063] Because the energy we need is highly time- and space-dependent, in order to utilize energy rationally and improve energy efficiency, it is necessary to store one form of energy in the same way or by converting it into another, and then release it in a specific energy form for future applications. Currently, the main way to generate green electricity is to develop green energy sources such as photovoltaics and wind power to replace fossil fuels.

[0064] 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.

[0065] Taking electrochemical energy storage as an example, this solution provides an energy storage device 200, which is applied to an energy storage system 400. The energy storage device 200 is equipped with a set of chemical batteries, which mainly use the chemical elements in the batteries as energy storage medium. The charging and discharging process is accompanied by the chemical reaction or change of the energy storage medium. 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 electrical energy is released for use, or transferred to places with a shortage of electricity for use.

[0066] Current energy storage applications are quite widespread, including generation-side energy storage, grid-side energy storage, and consumption-side energy storage. The corresponding energy storage devices include:

[0067] (1) Large-scale energy storage power stations (including multiple prefabricated energy storage modules) applied to wind power and photovoltaic power stations can help renewable energy power generation meet 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.

[0068] (2) The energy storage prefabricated cabin applied on the grid side mainly functions as peak regulation, frequency regulation and grid congestion relief. In terms of peak regulation, it 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.

[0069] (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 200, 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 400 when the electricity price is low and discharging the energy storage system 400 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 the energy storage system 400 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 electricity costs. 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.

[0070] In some embodiments, see Figure 1 , Figure 1 This is a schematic diagram of the structure of an energy storage system 400 according to an embodiment of this application. Figure 1 The embodiments are illustrated using a home energy storage scenario in user-side energy storage as an example. The energy storage device 200 in this application is not limited to an energy storage box in a home energy storage scenario.

[0071] This application provides an energy storage system 400, which includes a first power conversion device 410 (photovoltaic panel), a first user load 420 (household lighting fixture), a second user load 430 (e.g., household appliances such as air conditioners), and the energy storage device 200 of this application. The energy storage device 200 is a small energy storage box that can be wall-mounted on an outdoor wall. However, the energy storage device 200 is not limited to wall mounting and can also be placed in a user's residence in other ways. Specifically, the photovoltaic panel can convert solar energy into electrical energy during periods of low electricity prices, and the energy storage device 200 is used to store this electrical energy and supply it to lighting fixtures and household appliances during periods of high electricity prices, or to provide power during power outages / power failures.

[0072] Optionally, the first power conversion device 410 may include, but is not limited to, a photovoltaic panel, and the first power conversion device 410 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy and mechanical energy into electrical energy.

[0073] In some embodiments, see Figure 2 , Figure 2This is a schematic diagram of the structure of an energy storage system 400 according to another embodiment of this application, and this application Figure 2 The embodiments are illustrated using a shared energy storage scenario on the power generation / distribution side as an example. The energy storage device 200 in this application is not limited to a prefabricated energy storage module in a power generation / distribution energy storage scenario.

[0074] This application provides an energy storage system 400, which includes: a high-voltage cable 440, a first power conversion device 410, a second power conversion device 450, and the energy storage device 200 provided in this application. In some embodiments of the power generation scenario, the second power conversion device 450 can be 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 the energy storage device 200 through grid connection. The energy storage device 200 is connected to the high-voltage cable and outputs smooth electricity to the power consumption side of the distribution network, realizing peak shaving and frequency regulation, and stable grid operation; or, wind power... The conversion device is always connected to the high-voltage cable. Under normal power generation conditions, the power output of the wind power conversion device is supplied to the power consumption side of the distribution network through the high-voltage cable. 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 200 to reduce the curtailment rate of wind and solar power and improve the problem of new energy power generation consumption. When the power load is high, the power grid issues an instruction to transmit the power stored in the energy storage device 200 together with the high-voltage cable 440 in grid-connected mode to supply power to the power consumption 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.

[0075] In some embodiments on the distribution network side, the first power conversion device 410 can be a photovoltaic panel, and the energy storage device 200 is connected to the high-voltage cable 440 and installed downstream of the high-voltage cable 440 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 200, which can respond in a timely manner to act as a backup power source when the power grid / distribution network fails; or, it can provide power supply support to alleviate line congestion when the high-voltage cable 440 transmission line is blocked, and to delay the economic pressure caused by the expansion of the power grid / distribution capacity when the power grid is planned to be expanded.

[0076] Optionally, the first power conversion device 410 may include, but is not limited to, a wind power conversion device, and the second power conversion device 450 may include, but is not limited to, a photovoltaic panel. The first power conversion device 410 and the second power conversion device 450 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy, and mechanical energy into electrical energy.

[0077] In some embodiments, see Figure 3 , Figure 3This is a schematic diagram of the structure of an energy storage system 400 according to another embodiment of this application, and this application Figure 3 The embodiments are illustrated using an industrial and commercial energy storage scenario as an example. The energy storage device 200 in this application is not limited to an energy storage cabinet in an industrial and commercial energy storage scenario.

[0078] This application provides an energy storage system 400, which includes: an energy storage device 200, a high-voltage cable 440, a factory equipped with a first power conversion device 410, a photovoltaic-energy storage-charging station 460 equipped with a second power conversion device 450, and a vehicle 470. In some embodiments of industrial and commercial scenarios, the first power conversion device 410 can be a photovoltaic panel, which converts solar energy into electrical energy and stores it in the energy storage device 200 in the factory. In the event of a power grid failure, the energy storage device 200 provides power to ensure the safe and stable operation of the factory without interruption. Alternatively, when the factory's power load is high, the power grid issues an instruction to transmit the electricity stored in the energy storage device 200 in conjunction with the high-voltage cable 440 in a grid-connected mode to supply the factory with electricity, providing various services such as peak shaving / frequency regulation and backup for the power grid operation. In addition, the second power conversion device 450 can also be a photovoltaic panel, which converts solar energy into electrical energy and stores it in the energy storage device 200 of the photovoltaic-energy storage-charging station 460, directly charging the vehicle 470 through the photovoltaic-energy storage-charging station 460, which is fast and convenient.

[0079] Optionally, the first power conversion device 410 and the second power conversion device 450 may include, but are not limited to, a photovoltaic panel. The first power conversion device 410 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy, and mechanical energy into electrical energy.

[0080] Optionally, the energy storage device 200 may include, but is not limited to, energy storage applications such as 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, and may also be applied in multiple fields such as data centers, military equipment, aerospace, charging piles, and electric vehicles.

[0081] Optionally, the energy storage device 200 may include, but is not limited to, single-cell batteries, or battery modules, battery packs, battery clusters, power banks, energy storage cabinets / prefabricated energy storage compartments, and other battery integrated systems composed of single-cell batteries. The actual application form of the energy storage device 200 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 200. This application embodiment only uses a multi-cell battery of the energy storage device 200 as an example for illustration.

[0082] Optionally, the individual battery cells constituting the energy storage device 200 can be, but are not limited to, at least one of cylindrical, prismatic, prismatic, or other shaped batteries.

[0083] Optionally, the energy storage device 200 may include, but is not limited to, energy storage applications such as 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, and may also be applied in multiple fields such as data centers, military equipment, aerospace, charging piles, and electric vehicles.

[0084] Optionally, the energy storage device 200 may include battery modules, battery packs, battery clusters, mobile power supplies, energy storage cabinets / prefabricated energy storage compartments, and other battery integrated systems composed of individual batteries. The actual application form of the energy storage device 200 provided in this application embodiment can be, but is not limited to, the listed products, and can also be other application forms. This application embodiment does not strictly limit the application form of the energy storage device 200.

[0085] Alternatively, the single cell is not limited to at least one of cylindrical, square, prismatic, or other shaped cells.

[0086] Optionally, the single cell can be a rechargeable battery, which refers to a single cell that can be recharged after discharge to activate the active materials and continue to be used. The single cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and this application does not specifically limit it.

[0087] Please see Figures 4 to 7 This application provides an energy storage device 200, which includes a housing 210 and an end cap assembly 100. The housing 210 has a receiving cavity 211. The end cap assembly 100 is used to seal the receiving cavity 211. The end cap assembly 100 includes an end cap 110, a lower seal 180, and a one-way valve assembly 120. The end cap 110 and the lower seal 180 are located on the same side of the housing 210, and the housing 210, the lower seal 180, and the end cap 110 are arranged sequentially. The end cap 110 has a mounting groove 111, an air inlet 117, and a valve along the thickness direction of the end cap 110 (e.g., along the thickness direction of the end cap 110). Figure 5A first surface 112 and a second surface 113 are arranged opposite to each other in the X-direction (as shown in the middle X direction). The second surface 113 faces the receiving cavity 211. The mounting groove 111 is recessed in the first surface 112. The air inlet 117 penetrates the second surface 113 and the bottom wall of the mounting groove 111. The lower seal 180 has a through hole 181, which penetrates the two opposite surfaces of the lower seal 180 along the thickness direction and connects to the receiving cavity 211. The air inlet 117 and the mounting groove 111; the one-way valve assembly 120 includes a one-way valve sub-assembly 130 and a first interface 140, the one-way valve sub-assembly 130 is mounted in the mounting groove 111, and the one-way valve sub-assembly 130 is used to allow fluid to flow from the second surface 113 side to the first surface 112 side; the first interface 140 is disposed on the first surface 112 side of the end cap 110 and communicates with the one-way valve sub-assembly 130, and the first interface 140 is used to connect to an external collection pipe.

[0088] Understandably, the energy storage device 200 also includes an electrode assembly 220 located within the receiving cavity 211; the end cap assembly 100 is located on one side of the housing 210 and connected to the housing 210.

[0089] Understandably, the thickness direction of the end cap 110 is the height direction of the energy storage device 200, and the electrode assembly 220 and the end cap assembly 100 are arranged sequentially along the thickness direction of the end cap 110.

[0090] Understandably, when the one-way valve subassembly 130 is opened, the first surface 112 side and the second surface 113 side are connected, so that fluid flows from the second surface 113 side to the first surface 112 side. Specifically, in the energy storage device 200, the one-way valve subassembly 130 allows fluid on the side of the end cap 110 facing the electrode assembly 220 to flow to the side of the end cap 110 away from the electrode assembly 220. In other words, the one-way valve subassembly 130 is used to discharge the gas in the receiving cavity 211 to the outer periphery of the energy storage device 200, i.e., the first surface 112 side.

[0091] Understandably, in the terminology of this application, "fluid" includes, but is not limited to, flammable and explosive gases such as hydrogen and carbon monoxide, and liquids such as electrolytes.

[0092] Understandably, the first interface element 140 forms a first channel 143 to facilitate the collection and transmission of fluid, and to discharge the fluid from the energy storage device 200 through the external collection pipe.

[0093] Understandably, the lower seal 180 is located between the end cap 110 and the electrode assembly 220.

[0094] Understandably, the through hole of the lower seal 180 is connected to the receiving cavity 211 and the mounting groove 111 respectively. The one-way valve sub-assembly 130 is installed in the mounting groove 111. When the one-way valve sub-assembly 130 is opened, the receiving cavity, the through hole, the mounting groove and the first surface side are connected in sequence.

[0095] Understandably, the second surface 113 side, the air inlet 117, the mounting groove 111 and the first surface 112 side are connected in sequence.

[0096] Understandably, the opening of the mounting groove 111 penetrates the first surface 112, one end of the air inlet 117 penetrates the bottom wall of the mounting groove 111, and the other end penetrates the second surface 113.

[0097] In the end cap assembly 100 provided in this embodiment, the first interface 140 is disposed on the first surface 112 side of the end cap 110 and communicates with the one-way valve sub-assembly 130, so that when the one-way valve sub-assembly 130 is opened and fluid flows from the second surface 113 side to the first surface 112 side, the first interface 140 can be directly connected to an external collection pipe to collect the fluid delivered to the first surface 112 side, thereby preventing flammable and explosive gases in the fluid from accumulating on the first surface 112 side and directly igniting and exploding, thus improving the safety performance of the end cap assembly 100. Specifically, in the energy storage device 200, a large amount of flammable and explosive gas may be generated in the receiving cavity 211 of the energy storage device 200 due to overcharging, short circuit, or extreme conditions such as high temperature. The one-way valve sub-assembly 130 can be used to allow fluid to flow from the side of the end cap 110 facing the electrode assembly 220 to the side of the end cap 110 away from the electrode assembly 220, so as to balance the pressure on the first surface 112 side and the second surface 113 side, balance the gas pressure inside and outside the energy storage device 200, and prevent the energy storage device 200 from bulging, rupture, or even exploding, thereby improving the safety performance of the energy storage device 200. Furthermore, the first interface 140 is connected to an external collection pipe to collect and process the gas discharged from the inside of the energy storage device 200, preventing the flammable and explosive gas in the fluid from directly igniting and exploding on the surface of the energy storage device 200, further improving the safety performance of the energy storage device 200.

[0098] Understandably, in this application, the one-way valve subassembly 130 only allows fluid to flow from the second surface 113 side to the first surface 112 side, and does not allow fluid to flow from the first surface 112 side to the second surface 113 side.

[0099] Optionally, the first interface component 140 is used to connect to an external collection pipe, and the first interface component 140 and the external collection pipe are sealed together by an interference fit.

[0100] Optionally, in some embodiments, the first interface component 140 is a rigid interface pipe, and the material of the first interface component 140 includes, but is not limited to, stainless steel, cast iron, rigid polyvinyl chloride, etc.; in other embodiments, the first interface component 140 is a flexible interface pipe, and the material of the first interface component 140 includes, but is not limited to, rubber, flexible polyethylene, etc.

[0101] Optionally, the external collection pipe is a flexible hose, and the material of the external collection pipe includes, but is not limited to, rubber, soft polyethylene, etc.

[0102] Optionally, please also see Figures 7 to 11 The one-way valve subassembly 130 includes a sealing ring 131, a sealing sheet 132, a spring sheet 133, and a welding sheet 134. Along the thickness direction of the end cap 110, the sealing ring 131, the sealing sheet 132, the spring sheet 133, and the welding sheet 134 are sequentially arranged in the mounting groove 111, and the welding sheet 134 is welded to the inner wall of the mounting groove 111.

[0103] Understandably, the weld piece 134 is at least partially exposed on the first surface 112.

[0104] Understandably, the welding piece 134 engages with the spring piece 133.

[0105] In this embodiment, along the thickness direction of the end cap 110, the sealing ring 131, the sealing sheet 132, the spring sheet 133 and the welding sheet 134 are arranged in sequence, and the sealing ring 131, the sealing sheet 132, the spring sheet 133 and the welding sheet 134 are arranged in sequence in the mounting groove 111. When the air pressure on the first surface 112 side and the second surface 113 side of the end cap 110 is balanced, the one-way valve subassembly 130 is in the closed state. The welding piece 134 is welded to the inner wall of the mounting groove 111. At the same time, the welding piece 134 engages with the spring piece 133, so that the spring piece 133 is compressed and pressed against the sealing piece 132. The side of the sealing piece 132 away from the spring piece 133 presses against the sealing ring 131. In other words, there is no gap between the sealing piece 132 and the sealing ring 131, thereby achieving a sealed connection between the one-way valve subassembly 130 and the end cap 110, preventing external gas from entering the second surface 113 side from the first surface 112 side of the end cap 110. When the energy storage device 200 continuously generates a large amount of gas, the gas pressure on the second surface 113 side of the end cap 110 increases and the pressure difference between the second surface 113 and the first surface 112 is greater than the first threshold. The gas is collected through the through hole 181 of the lower seal 180 to the second surface 113 side, and further collected to the side of the sealing sheet 132 away from the spring sheet 133. Under the action of air pressure, the sealing sheet 132 is pushed against the first surface 112 side by the airflow from the second surface 113 side to compress the spring sheet 133 and create a gap between the sealing sheet 132 and the sealing ring 131. The gas flows from the gap between the sealing ring 131 and the sealing sheet 132 and the gap between the sealing sheet 132 and the side wall of the mounting groove 111 to the side of the sealing sheet 132 near the first surface 112, and flows out of the end cap 110 from the exhaust hole 1334 of the spring sheet 133 and the snap hole 1341 of the welding piece 134 to balance the air pressure on the first surface 112 side and the second surface 113 side of the end cap 110.

[0106] Understandably, in the terminology of this application, "first threshold" refers to a preset critical value of the air pressure difference between the second surface 113 and the first surface 112. At this preset critical value, the air pressure on the second surface 113 side can press against the sealing sheet 132 from the second surface 113 side towards the first surface 112 side, so that there is a gap between the sealing sheet 132 and the sealing ring 131, thereby causing the one-way valve subassembly 130 to open. This application does not limit the specific value of the first threshold.

[0107] Understandably, the welding piece 134 has a snap-fit ​​hole 1341 that penetrates two opposing surfaces of the welding piece 134 along the thickness direction to connect the first surface 112 side and the side of the welding piece 134 opposite to the first surface 112.

[0108] Understandably, the spring 133 has the vent 1334, which extends through two opposing surfaces of the spring 133 in the thickness direction, so that gas flowing to the side of the sealing sheet 132 near the first surface 112 can exit the end cap 110.

[0109] In some embodiments, the end cap 110 further has a first groove 114 that penetrates the first surface 112 and surrounds the outer periphery of the one-way valve subassembly 130. The first interface 140 includes a first flange portion 141 and a first interface portion 142 connected together. The first flange portion 141 is disposed in the first groove 114. Along the thickness direction of the end cap 110, the depth of the first groove 114 is h1, and the thickness of the first flange portion 141 is h2. Then, the end cap assembly 100 satisfies the relationship: h1-h2≥0.3mm.

[0110] Specifically, the values ​​of h2-h1 can be, but are not limited to, 0.3mm, 0.31mm, 0.34mm, 0.38mm, 0.4mm, 0.42mm, 0.45mm, 0.48mm, 0.5mm, 0.52mm, 0.55mm, 0.58mm, and 0.6mm.

[0111] Understandably, the first groove 114 is disposed around the outer periphery of the weld piece 134.

[0112] Understandably, the first flange portion 141 is disposed around the outer periphery of the first interface portion 142.

[0113] Understandably, the depth of the first groove 114 is greater than the thickness of the first flange portion 141, so that when the first flange portion 141 is provided in the first groove 114, the first flange portion 141 can be prevented from protruding from the first surface 112.

[0114] In this embodiment, the first interface component 140 includes a first flange portion 141 and a first interface portion 142 connected together. The first flange portion 141 and the first interface portion 142 are arranged sequentially along the thickness direction of the end cap component 110. The first flange portion 141 is disposed in the first groove 114 and connected to the end cap component 110 to improve the sealing performance between the first interface component 140 and the end cap component 110, and to prevent the fluid discharged from the one-way valve subassembly 130 from overflowing from the gap between the first flange portion 141 and the end cap component 110. The first interface portion 142 facilitates the connection between the first interface component 140 and the external collection pipe to improve the connection stability between the first interface component 140 and the external collection pipe. Furthermore, the end cap assembly 100 satisfies the relationship: h1-h2≥0.3mm. When the first flange portion 141 is disposed in the first groove 114, the first flange portion 141 can be completely accommodated in the first groove 114. When an insulating film is disposed on the first surface 112 side of the end cap 110, the flatness of the insulating film can be avoided due to the first flange portion 141 protruding from the first surface 112, so that the insulating film can fully exert its insulating function.

[0115] Understandably, the insulating film is used to prevent short-circuit connections between two adjacent energy storage devices 200.

[0116] Optionally, in some embodiments, the first flange portion 141 is laser welded to the bottom wall and / or side wall of the first groove 114 to prevent fluid from flowing out from the gap between the first flange portion 141 and the end cap 110.

[0117] Optionally, along the thickness direction of the end cap 110, the depth h1 of the first groove 114 is in the range of 0.5mm≤h1≤4mm, so that the first groove 114 can completely accommodate the first flange portion 141, and the end cap 110 has good structural strength.

[0118] Specifically, the depth h1 of the first groove 114 can be, but is not limited to, 0.5mm, 0.8mm, 1mm, 1.5mm, 2mm, 2.5mm, 2.8mm, 3mm, 3.2mm, 3.5mm, 3.8mm and 4mm.

[0119] Optionally, along the thickness direction of the end cap 110, the thickness h2 of the first flange portion 141 is in the range of 0.2mm≤h2≤3.7mm, so that the first flange portion 141 can achieve a sealed connection with the bottom wall and / or side wall of the first groove 114, thereby improving the structural stability of the first interface member 140 disposed in the first groove 114.

[0120] Specifically, the thickness h2 of the first flange portion 141 can be, but is not limited to, 0.2mm, 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 2.2mm, 2.5mm, 2.8mm, 3mm, 3.1mm, 3.3mm, 3.5mm and 3.7mm.

[0121] Understandably, the first interface portion 142 has the first channel 143 to facilitate the collection and transfer of fluid, and to discharge the fluid from the end cap assembly 100 through the external collection pipe.

[0122] In some embodiments, if the thickness of the end cap 110 is h3 along the thickness direction of the end cap 110, then the end cap assembly 100 satisfies the relationship: 0.2×h3≤h1≤0.8×h3.

[0123] Specifically, the value of h1 can be, but is not limited to, 0.2×h3, 0.25×h3, 0.3×h3, 0.35×h3, 0.4×h3, 0.45×h3, 0.5×h3, 0.6×h3, 0.65×h3, 0.7×h3, 0.75×h3, and 0.8×h3.

[0124] In this embodiment, when the end cap assembly 100 satisfies the relationship 0.2×h3≤h1≤0.8×h3, the depth of the first groove 114 is within a reasonable range. On the one hand, the first groove 114 can completely accommodate the first flange portion 141 to prevent the first flange portion 141 from protruding from the first surface 112, and at the same time realize the sealed connection between the first flange portion 141 and the end cap 110 to prevent fluid leakage from the gap between the first flange portion 141 and the end cap 110. On the other hand, excessive hollowing out of the end cap 110 can be avoided, which would reduce the structural strength of the end cap 110. When the pressure difference between the first surface 112 side and the second surface 113 side of the end cap 110 reaches the first threshold and causes the one-way valve sub-assembly 130 to open, the end cap 110 can withstand the impact force of the air pressure on the second surface 113 side, thus ensuring the structural integrity of the end cap 110. The end cap assembly 100 has a better service life and ultimately improves the safety performance of the energy storage device 200. When the value of h1 is too large, the depth of the first groove 114 is too large, which greatly reduces the structural strength of the periphery of the mounting groove 111 of the end cap 110. When the pressure difference between the second surface 113 and the first surface 112 of the end cap 110 reaches a first threshold and causes the one-way valve subassembly 130 to open, the air pressure on the second surface 113 of the end cap 110 will exert a certain impact force on the one-way valve subassembly 130, and will also exert an impact force on a portion of the end cap 110 around the mounting groove 111. If the structural strength of the end cap 110 is too poor, after a period of use, the end cap 110 is prone to bending, shortening the service life of the end cap assembly 100. When the value of h1 is too small, the depth of the first groove 114 is too small, and the first groove 114 cannot completely accommodate the first flange portion 141, so that the first flange portion 141 may protrude from the first surface 112, affecting the flatness of the insulating film on the first surface 112 side of the end cap 110, causing abnormal protrusions after the insulating film is installed, which may cause a decrease in the insulation performance of the insulating film and reduce the reliability of the end cap assembly 100.

[0125] Optionally, along the thickness direction of the end cap 110, the thickness h3 of the end cap 110 is in the range of 1mm≤h3≤5mm, so that the end cap 110 has better structural strength and is easy to connect and assemble with the housing 210.

[0126] Specifically, the thickness h3 of the end cap 110 can be, but is not limited to, 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 2.1mm, 2.3mm, 2.5mm, 2.8mm, 3mm, 3.2mm, 3.5mm, 3.8mm, 4mm, 4.1mm, 4.3mm, 4.5mm, and 5mm.

[0127] Please see also Figures 12 to 14 In some embodiments, the first interface 140 satisfies one of the following conditions: the outer periphery of the first interface portion 142 is provided with an external thread so that the first interface portion 142 is threadedly connected to an external collection pipe; the inner side of the first interface portion 142 is provided with an internal thread so that the first interface portion 142 is threadedly connected to an external collection pipe.

[0128] Understandably, Figures 4 to 10 The outer periphery of the first interface portion 142 of the end cap assembly 100 shown in the embodiment is provided with the external thread; Figures 12 to 14 The end cap assembly 100 shown in the embodiment has the internal thread on the outer periphery of the first interface portion 142.

[0129] In this embodiment, by providing external threads on the outer periphery of the first interface portion 142 or internal threads on the inner side of the first interface portion 142, the sealing performance when the first interface portion 142 is connected to the external collection pipe is improved. When fluid from the second surface 113 side of the end cap 110 flows from the one-way valve sub-assembly 130 to the first surface 112 side, the fluid enters the first channel 143 enclosed by the first interface portion 140 and is connected to the outside through the external collection pipe, thereby preventing fluid leakage from the gap between the first interface portion 142 and the external collection pipe. Simultaneously, the threaded connection between the first interface portion 142 and the external collection pipe improves the structural stability of the connection, preventing the external collection pipe from detaching from the first interface portion 142, improving the reliability of the end cap assembly 100, and ultimately enhancing the safety performance of the energy storage device 200.

[0130] Understandably, when the outer periphery of the first interface portion 142 is provided with external threads, the external collection pipe is sleeved on the outer periphery of the first interface portion 142, and the internal threads of the external collection pipe are threadedly connected to the external threads.

[0131] Optionally, when the outer periphery of the first interface portion 142 is provided with external threads, the inner diameter of the external collection pipe is smaller than the outer diameter of the first interface portion 142, so as to achieve an interference fit between the first interface portion 142 and the external collection pipe.

[0132] Understandably, when the inner side of the first interface portion 142 is provided with an internal thread, the external collection pipe passes through the first interface portion 142, and the external thread of the external collection pipe is threadedly connected to the internal thread.

[0133] Optionally, when the inner side of the first interface portion 142 is provided with an external thread, the outer diameter of the external collection pipe is larger than the inner diameter of the first interface portion 142, so as to achieve an interference fit between the first interface portion 142 and the external collection pipe.

[0134] Understandably, the option of having external threads on the outer periphery of the first interface portion 142 is superior to the option of having internal threads on the inner side of the first interface portion 142. In the option of having external threads on the outer periphery of the first interface portion 142, the threads can be prevented from occupying the space of the first channel 143 enclosed by the first interface portion 142, which is more conducive to the discharge of fluid through the external collection pipe and avoids the accumulation of fluid on the side of the first surface 112.

[0135] In some embodiments, the outer periphery of the first interface portion 142 is provided with an external thread, the inner diameter of the first interface portion 142 is D1, and the outer diameter of the first interface portion 142 is D2. Then the first interface component 140 satisfies the relationship: D2-D1≥0.8×h2.

[0136] Specifically, the value of D2-D1 can be, but is not limited to, 0.8×h2, 0.82×h2, 0.85×h2, 0.88×h2, 0.9×h2, 1×h2, 1.2×h2, etc.

[0137] Understandably, the value of (D2-D1) / 2 can characterize the thickness of the first interface portion 142 in its radial direction.

[0138] In this embodiment, when the first interface component 140 satisfies the relationship D2-D1≥0.8×h2, the thickness of the first interface portion 142 along its radial direction and the thickness of the first flange portion 141 are both within a reasonable range. On the one hand, the first interface portion 142, as the first channel 143 for fluid transmission, has sufficient rigidity, enabling it to have good resistance to deformation and fracture, thus facilitating the transmission of fluid flowing from the one-way valve subassembly 130 to the external collection pipe. On the other hand, the first flange portion 141, as a key part connecting to and bearing force with the end cap component 110, establishes a numerical relationship between D2-D1 and h2, ensuring good connection strength between the first flange portion 141 and the first interface portion 142. This prevents the first interface portion 142 from breaking off from the first flange portion 141 due to local stress, extending the service life of the first interface component 140. This, in turn, improves the performance of the end cap assembly 100 and ultimately enhances the safety performance of the energy storage device 200.

[0139] Optionally, the inner diameter D1 and the outer diameter D2 of the first interface portion 142 satisfy the relationship: 0.8mm≤D2-D1≤10mm, so that the first interface portion 142 and its outer peripheral thread have sufficient structural strength, which facilitates the transmission of fluid and improves the stability of the connection with the external collection pipe.

[0140] Specifically, the values ​​of D2-D1 can be, but are not limited to, 0.8mm, 1mm, 1.3mm, 2mm, 2.5mm, 3mm, 3.8mm, 4mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, and 10mm.

[0141] Please see also Figure 9 and Figure 10 In some embodiments, the height of the first interface portion 142 along the thickness direction of the end cap 110 is h4, and the end cap assembly 100 satisfies the relationship: 0.5×D2≤h4≤1.5×D2.

[0142] Specifically, the value of h4 can be, but is not limited to, 0.5×D2, 0.6×D2, 0.7×D2, 0.8×D2, 0.9×D2, 1×D2, 1.1×D2, 1.2×D2, 1.3×D2, 1.4×D2, and 1.5×D2.

[0143] Understandably, the height of the first interface portion 142 is positively correlated with the outer diameter of the first interface portion 142.

[0144] Understandably, as the outer diameter of the first interface portion 142 increases, the force (such as axial tension, torque, etc.) that the first interface portion 142 needs to transmit also increases, requiring a sufficiently large length to distribute the pressure and avoid deformation, stripping, or breakage of the external thread of the first interface portion 142 due to excessive local stress.

[0145] In this embodiment, when the end cap assembly 100 satisfies the relationship 0.5×D2≤h4≤1.5×D2, the height of the first interface portion 142 is within a reasonable range. By establishing a numerical relationship between the height of the first interface portion 142 and its outer diameter, the height of the first interface portion 142 can be adapted to its outer diameter. The height of the first interface portion 142 disperses the force that the external thread of the first interface portion 142 needs to transmit, thereby reducing the local stress of the first interface portion 142 and avoiding deformation, stripping, or breakage of the external thread of the first interface portion 142 due to excessive local stress. This results in better sealing performance when the first interface portion 142 is connected to the external collection pipe. When the value of h4 is too large, the first interface portion 142 may occupy too much space on the first surface 112 side of the end cap 110. When the end cap assembly 100 is assembled on the energy storage device 200, it increases the height of the energy storage device 200, which is not conducive to the miniaturization design of the energy storage device 200 and results in excessive material consumption, increasing the manufacturing cost of the first interface portion 140. When the value of h4 is too small, when the first interface portion 142 is connected to the external collection pipe, it may cause excessive local stress in the first interface portion 142, leading to deformation, stripping, or breakage of the external thread of the first interface portion 142. This results in poor sealing performance between the first interface portion 142 and the external collection pipe, and gas may leak from the gap between the first interface portion 142 and the external collection pipe. In addition, the external collection pipe may also detach directly from the first interface portion 142, resulting in poor connection stability between the first interface portion 142 and the external collection pipe.

[0146] Optionally, the height h4 of the first interface portion 142 is in the range of 3mm≤h4≤20mm, so that the first interface portion 142 can be stably connected to the external collection pipe, and the external thread of the first interface portion 142 can be prevented from deforming, slipping or breaking due to excessive local stress, thereby making the connection between the first interface portion 142 and the external collection pipe have better sealing performance.

[0147] Specifically, the height h4 of the first interface portion 142 can be, but is not limited to, 3mm, 4mm, 5mm, 6mm, 8mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm and 20mm.

[0148] Please see also Figures 15 to 19 In some embodiments, the one-way valve subassembly 130 includes a sealing ring 131, a sealing sheet 132, a spring sheet 133, and a welding sheet 134. Along the thickness direction of the end cap 110, the sealing ring 131, the sealing sheet 132, the spring sheet 133, and the welding sheet 134 are sequentially disposed in the mounting groove 111; the first interface member 140 is connected to the welding sheet 134.

[0149] Understandably, the welding piece 134 engages with the spring piece 133.

[0150] Understandably, the first interface component 140 is welded to the end cap component 110.

[0151] Optionally, the connection between the first interface component 140 and the welding piece 134 can be that the first interface component 140 and the welding piece 134 are separate structures, and the first interface component 140 and the welding piece 134 are connected by welding or other means; or the first interface component 140 and the welding piece 134 can be an integrally formed structure.

[0152] Understandably, in this embodiment, the first interface member 140 is at least partially located within the mounting groove 111 and connected to the inner wall of the mounting groove 111.

[0153] In this embodiment, when the air pressure on the first surface 112 side and the second surface 113 side of the end cap 110 is balanced, the one-way valve subassembly 130 is in a closed state. The welding piece 134 is connected to the first interface piece 140, and the first interface piece 140 is connected to the end cap 110. At the same time, the welding piece 134 engages with the spring piece 133, so that the welding piece 134 can compress the spring piece 133 and make the spring piece 133 press against the sealing piece 132. The side of the sealing piece 132 away from the spring piece 133 presses against the sealing ring 131. In other words, there is no gap between the sealing piece 132 and the sealing ring 131, thereby achieving a sealed connection between the one-way valve subassembly 130 and the end cap 110, preventing external gas from entering the second surface 113 side from the first surface 112 side of the end cap 110. When the energy storage device 200 continuously generates a large amount of gas, the gas pressure on the second surface 113 side of the end cap 110 increases and the pressure difference between the second surface 113 and the first surface 112 is greater than the first threshold. The gas then gathers through the through hole 181 of the lower seal 180 to the second surface 113 side and further gathers to the side of the sealing sheet 132 away from the spring sheet 133. Under the action of air pressure, the sealing sheet 132 is pushed against the first surface 112 from the second surface 113 side to compress the spring sheet 133 and create a gap between the sealing sheet 132 and the sealing ring 131. Gas flows from the gap between the sealing ring 131 and the sealing sheet 132 and the gap between the sealing sheet 132 and the side wall of the mounting groove 111 to the side of the sealing sheet 132 near the first surface 112, and flows out of the end cap 110 from the exhaust hole 1334 of the spring sheet 133 and the snap-fit ​​hole 1341 of the welding piece 134 to balance the air pressure on the first surface 112 side and the second surface 113 side of the end cap 110. In this solution, by connecting the welding piece 134 to the first interface piece 140, it is not necessary to additionally provide the first groove 114 on the first surface 112 side to achieve communication between the first interface piece 140 and the one-way valve sub-assembly 130. At the same time, the sealing performance between the one-way valve assembly 120 and the end cap 110 can be guaranteed. The structure of the solution provided in this application embodiment is simpler. Compared with the solution of first welding the welding piece 134 to the end cap 110 and then welding the first interface piece 140 to the outer periphery of the one-way valve sub-assembly 130, this solution can reduce welding steps, improve the production efficiency of the end cap assembly 100, reduce the risk of welding defects, improve the connection reliability between the one-way valve assembly 120 and the end cap 110, and further improve the performance of the end cap assembly 100.

[0154] Understandably, during the installation process of the first interface piece 140 and the one-way valve sub-assembly 130: firstly, the first interface piece 140 and the welding piece 134 are integrated into a single structure; then, the sealing ring 131, the sealing piece 132, and the spring piece 133 are placed in the mounting groove 111; the welding piece 134 engages with the spring piece 133; by applying pressure from the first surface 112 to the second surface 113 to the first interface piece 140, the spring piece 133 and the sealing ring 131 are compressed; furthermore, the first interface piece 140 is welded to the inner wall of the mounting groove 111.

[0155] Optionally, the mounting groove 111 includes a first sub-groove 1111 and a second sub-groove 1112 that are connected to each other. The first sub-groove 1111 and the second sub-groove 1112 are coaxially arranged. The first sub-groove 1111 is recessed in the first surface 112. The air inlet 117 penetrates the bottom wall of the second sub-groove 1112. The radial dimension of the first sub-groove 1111 is larger than the radial dimension of the second sub-groove 1112. The sealing ring 131 and the sealing piece 132 are located in the second sub-groove 1112. The spring piece 133 is engaged with the welding piece 134. The welding piece 134 and the first interface piece 140 are located in the first sub-groove 1111.

[0156] Understandably, the first surface 112 side, the first sub-slot 1111, the second sub-slot 1112, the air inlet 117 and the second surface 113 side are connected in sequence.

[0157] Understandably, a first step surface and a second step surface are formed at the connection between the first sub-slot 1111 and the second sub-slot 1112. The first step surface is the bottom wall of the first sub-slot 1111, and the second step surface is the inner peripheral wall of the second sub-slot 1112. The first step surface and the second step surface are arranged perpendicularly.

[0158] In this embodiment, the sealing ring 131 and the sealing sheet 132 are located in the second sub-groove 1112. The sealing ring 131 abuts against the bottom wall of the second sub-groove 1112 and the second stepped surface. The sealing sheet 132 abuts against the side of the sealing ring 131 opposite to the bottom wall of the second sub-groove 1112, and also abuts against the second stepped surface. The spring piece 133 is located on the side of the sealing sheet 132 opposite to the sealing ring 131. The spring piece 133 is engaged with the welding piece 134. When the welding piece 134 and the first interface member 140 are installed in the first sub-groove 1111, with the bottom of the first interface member 140 connected to the first stepped surface, the spring piece 133 is compressed and abuts against the sealing sheet 132, so that there is no gap between the sealing sheet 132 and the sealing ring 131. When the sealing sheet 132 is pushed against the sealing ring 131 in the direction away from the sealing sheet 131 under the action of air pressure, there is a gap between the sealing sheet 132 and the sealing ring 131. At the same time, the side of the sealing sheet 132 is offset from the second step surface. The airflow flows from the second surface 113 side, the gap between the sealing sheet 132 and the sealing ring 131, and the side of the sealing sheet 132 to the exhaust hole 1334 of the spring sheet 133 and the snap-fit ​​hole 1341 of the welding sheet 134, and then flows to the external collection pipe through the first interface 140.

[0159] In some embodiments, the welding piece 134 has a snap-fit ​​hole 1341; the spring piece 133 includes an elastic portion 1331, a through portion 1332, and a mating portion 1333 that are bent and connected in sequence. The elastic portion 1331 and the mating portion 1333 are bent toward the same side relative to the through portion 1332. The through portion 1332 passes through the snap-fit ​​hole 1341. The elastic portion 1331 is located on the side of the welding piece 134 facing the sealing piece 132. The elastic portion has a vent hole 1334 that penetrates two opposing surfaces of the elastic portion 1331 along the thickness direction. The mating portion 1333 is located on the side of the welding piece 134 away from the sealing piece 132.

[0160] Understandably, along the thickness direction of the end cap, the elastic part 1331, the through part 1332, and the mating part 1333 are connected in sequence.

[0161] Understandably, along the thickness direction of the end cap, the elastic portion 1331 is located between the welding piece 134 and the sealing piece 132.

[0162] Understandably, the vent 1334 is connected to the side of the elastic part 1331 facing the second step surface and the side of the elastic part 1331 away from the second step surface.

[0163] Understandably, the through portion 1332 is connected to the first interface portion 142 of the first interface member 140.

[0164] In this embodiment, the elastic part 1331 and the mating part 1333 are bent toward the same side relative to the through part 1332, and along the thickness direction of the end cap 110, the elastic part 1331 and the mating part 1333 are located on opposite sides of the through part 1332. The elastic part 1331 and the mating part 1333 cooperate with each other so that the through part 1332 passes through the snap-fit ​​hole 1341, thereby realizing the welding piece 134 snapping the spring piece 133. When the first interface member 140 is connected to the end cap member 110, the spring piece 133 is engaged by the welding piece 134. At this time, the elastic part 1331 is located between the welding piece 134 and the sealing piece 132. The elastic part 1331 is in a pre-compressed state to generate an elastic restoring force on the sealing piece 132, thereby causing the sealing piece 132 to abut against the sealing ring 131 and preventing external gas from entering the second surface 113 side from the first surface 112 side. More specifically, when the pressure difference between the second surface 113 and the first surface 112 of the end cap 110 exceeds a first threshold, under the action of air pressure, the airflow impacts the sealing sheet 132 and moves it toward the first surface 112, so that the distance between the sealing sheet 132 and the welding sheet 134 is further reduced, the elastic part 1331 is compressed, there is a gap between the sealing ring 131 and the sealing sheet 132, the airflow flows from the gap between the sealing ring 131 and the sealing sheet 132 to the elastic part 1331, and is further transmitted to the first interface part 142 through the exhaust hole 1334 of the elastic part 1331 and the through part 1332, so as to transmit the gas to the outside of the end cap assembly 100.

[0165] In some embodiments, the inner diameter of the first interface portion 142 is D1, and the maximum radial dimension of the mating portion 1333 along the radial direction is D3. Then the end cap assembly 100 satisfies the relationship: 2mm≤D1-D3≤6mm.

[0166] Specifically, the values ​​of D1-D3 can be, but are not limited to, 2mm, 2.2mm, 2.5mm, 2.8mm, 3mm, 3.2mm, 3.5mm, 3.8mm, 4mm, 4.2mm, 4.5mm, 4.9mm, 5mm, 5.2mm, 5.8mm, and 6mm.

[0167] Understandably, the inner diameter of the first interface portion 142 is the radial dimension of the first channel 143 formed by the first interface portion 142.

[0168] In this embodiment, when the end cap assembly 100 satisfies the relationship 2mm≤D1-D3≤6mm, the inner diameter of the first interface portion 142 and the maximum radial dimension of the mating portion 1333 are both within a reasonable range. On one hand, the mating portion 1333 abuts against the welding piece 134 on the side near the through portion 1332, and the contact area between the mating portion 1333 and the welding piece 134 is within a reasonable range, so that the spring piece 133 and the welding piece 134 have good connection stability. On the other hand, controlling the inner diameter D1 of the first interface portion 142 and the maximum radial dimension of the mating portion 1333 can prevent the size of the first interface portion 142 from being too large, which would reduce the structural strength of the end cap 110, improve the performance of the end cap assembly 100, and ultimately improve the safety performance of the energy storage device 200. When the values ​​of D1-D3 are too large, the inner diameter D1 of the first interface portion 142 is too large or the maximum radial dimension of the mating portion 1333 is too small, resulting in a small contact area between the mating portion 1333 and the welding piece 134. This reduces the structural stability of the welding piece 134 engaging the spring piece 133, which may affect the function and role of the one-way valve subassembly 130. When the values ​​of D1-D3 are too small, the inner diameter D1 of the first interface portion 142 is too small or the maximum radial dimension of the mating portion 1333 is too large, which is not conducive to the airflow transmission to the external collection pipe.

[0169] Optionally, along the radial direction of the mating part 1333, the maximum radial dimension D3 of the mating part 1333 is in the range of 1.5mm≤D3≤20mm, so that the mating part 1333 and the welding piece 134 have a large contact area, thereby achieving connection stability between the spring piece 133 and the welding piece 134.

[0170] Specifically, the maximum radial dimension D3 of the mating part 1333 can be, but is not limited to, 1.5mm, 3mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, and 20mm.

[0171] In some embodiments, the inner diameter of the through portion 1332 is D4, and the thickness of the spring piece 133 is T. Then the end cap assembly 100 satisfies the relationship: 5T≤D3-D4≤10T.

[0172] Specifically, the values ​​of D3-D4 can be, but are not limited to, 5T, 5.2T, 5.5T, 5.8T, 6T, 6.2T, 6.8T, 7T, 7.5T, 7.8T, 8T, 8.2T, 8.5T, 9T, 9.5T, and 10T.

[0173] Understandably, 5T≤D3-D4≤10T can also be expressed as 3T≤D3-D4-2T≤8T, wherein the mating part 1333 is a ring structure, the mating part 1333 is arranged around the outer periphery of the through part 1332 and connected to the through part 1332, and D3-D4-2T represents twice the width of the ring structure.

[0174] In this embodiment, when the end cap assembly 100 satisfies the relationship 5T≤D3-D4≤10T, the end cap assembly 100 also satisfies 3T≤D3-D4-2T≤8T. The inner diameter of the through part 1332 and the maximum radial dimension of the mating part 1333 are both within a reasonable range. On the one hand, this makes the width of the annular mating part 1333 also within a reasonable range, thereby making the mating part 1333 and the welding piece 134 have a sufficiently large contact area. During the elastic deformation of the elastic part 1331, the mating part 1333 can be prevented from detaching from the welding piece 134, thus preventing the spring piece 133 from separating from the welding piece 134 and improving the connection stability between the welding piece 134 and the spring piece 133. On the other hand, by correlating the values ​​of D3 and D4, it is possible to avoid the inner diameter of the through part 1332 being too large, which would cause the edge of the spring piece 133 to crack. This is beneficial to extending the service life of the spring piece 133, ensuring the function and role of the one-way valve sub-assembly 130, balancing the internal and external air pressure of the energy storage device 200 in a timely manner, improving the safety and reliability of the energy storage device 200, and ultimately improving the safety performance of the energy storage device 200.

[0175] Please see Figures 20 to 22 In some embodiments, the end cap 110 further has an explosion-proof hole 115, which penetrates the first surface 112 and the second surface 113; the end cap assembly 100 further includes an explosion-proof valve assembly 150, which includes an explosion-proof valve sub-assembly 160 and a second interface 170. The explosion-proof valve sub-assembly 160 is mounted on the end cap 110 and covers the explosion-proof hole 115; the second interface 170 is disposed on the first surface 112 side and communicates with the explosion-proof valve sub-assembly 160, and the second interface 170 is used to connect to an external collection pipe.

[0176] Understandably, the explosion-proof hole 115 is offset from the mounting groove 111.

[0177] Understandably, the explosion-proof valve subassembly 160 is rotatably connected to the end cap 110.

[0178] Understandably, the second interface element 170 forms a second channel 174 to facilitate the collection and transfer of fluid, and to discharge the fluid from the end cap assembly 100 through the external collection pipe.

[0179] Understandably, in Figure 21 In this embodiment, the explosion-proof valve sub-assembly 160 covers the explosion-proof hole 115; in Figure 22 In this embodiment, the explosion-proof valve sub-assembly 160 is in an open state relative to the explosion-proof hole 115, and the explosion-proof valve sub-assembly 160 rotates relative to the end cap 110.

[0180] In this embodiment, the second interface component 170 is disposed on the first surface 112 side and communicates with the explosion-proof valve sub-assembly 160. When the pressure difference between the second surface 113 side and the first surface 112 side of the end cap component 110 reaches a second threshold, the explosion-proof valve sub-assembly 160 folds relative to the end cap component 110 toward the side away from the second surface 113, so that the fluid on the second surface 113 side can flow through the explosion-proof hole 115 to the first surface 112 side and enter the second channel 174 formed by the second interface component 170, and then flow out of the end cap assembly 100 through the external collection pipe, so as to avoid the accumulation of flammable and explosive gases in the fluid on the first surface 112 side and cause fire and explosion, thereby improving the safety and reliability of the energy storage device 200. When the internal air pressure of the energy storage device 200 rises abnormally, the explosion-proof valve sub-assembly 160 bursts in time to release the pressure and prevent the energy storage device 200 from exploding. At the same time, through the cooperation of the second interface 170 and the external collection pipe, the ejected airflow is collected, further improving the safety performance of the energy storage device 200 and ultimately enhancing the safety performance of the energy storage device 200.

[0181] Understandably, in the terminology of this application, "second threshold" refers to a preset critical value of the air pressure difference between the second surface 113 and the first surface 112. At this preset critical value, the air pressure on the second surface 113 side can cause the explosion-proof valve sub-assembly 160 to rupture, thereby causing the explosion-proof valve sub-assembly 160 to fold over and open the explosion-proof hole 115, facilitating the flow of fluid from the second surface 113 side towards the first surface 112 side. This application does not limit the specific value of the second threshold.

[0182] Understandably, in some embodiments, the end cap assembly 100 includes an explosion-proof valve subassembly 160 and a second interface 170; in other embodiments, the end cap assembly 100 includes an explosion-proof valve subassembly 160, a second interface 170, and a one-way valve subassembly 130; in still other embodiments, the end cap assembly 100 includes an explosion-proof valve subassembly 160, a second interface 170, a one-way valve subassembly 130, and a first interface 140; and in still other embodiments, the end cap assembly 100 includes an explosion-proof valve subassembly 160, a one-way valve subassembly 130, and a first interface 140.

[0183] Optionally, the second interface component 170 is a flexible interface pipe, and the material of the first interface component 140 includes, but is not limited to, rubber, soft polyethylene, etc.

[0184] Please see Figures 20 to 24 In some embodiments, along the length direction of the end cap 110 (e.g. Figure 23 In the Y direction (as shown), the width of the explosion-proof valve sub-assembly 160 is W1, and the inner diameter of the second interface component 170 is W2. Then the end cap assembly 100 satisfies the relationship: W2≥2×(W1+3mm).

[0185] Specifically, the value of W2 can be, but is not limited to, 2×(W1+3mm), 2.2×(W1+3mm), 2.5×(W1+3mm), 2.8×(W1+3mm), 3×(W1+3mm), 3.5×(W1+3mm), and 4×(W1+3mm).

[0186] Understandably, along the length of the end cap 110, the inner diameter of the second interface 170 is greater than the width of the explosion-proof valve subassembly 160.

[0187] In this embodiment, when the end cap assembly 100 satisfies the relationship W2≥2×(W1+3mm), the inner diameter of the second interface member 170 is within a reasonable range. By relating the inner diameter of the second interface member 170 to the width of the explosion-proof valve sub-assembly 160, when the explosion-proof valve sub-assembly 160 is opened and rotated relative to the end cap member 110, the explosion-proof valve sub-assembly 160 can fold within the second channel 174 formed by the second interface member 170. This avoids interference from the inner wall of the second interface member 170 with the explosion-proof valve sub-assembly 160, thus preventing it from affecting pressure relief and improving the performance of the end cap assembly 100. Furthermore, the inner diameter W2 of the second interface member 170 is within a reasonable range, ensuring that the space of the second channel 174 formed by the second interface member 170 is within a reasonable range. This facilitates the containment of a large amount of gas ejected from the explosion-proof hole 115 and further transmission to an external collection pipe, giving the end cap assembly 100 high safety and reliability.

[0188] Optionally, the inner diameter W2 of the second interface 170 is in the range of 4mm≤W2≤50mm, so that the second interface portion 172 can provide space for the explosion-proof valve subassembly 160 to fold.

[0189] Specifically, the inner diameter W2 of the second interface member 170 can be, but is not limited to, 4mm, 8mm, 10mm, 12mm, 16mm, 18mm, 20mm, 22mm, 25mm, 28mm, 30mm, 32mm, 35mm, 38mm, 40mm, 42mm, 45mm, 46mm, 48mm and 50mm.

[0190] In some embodiments, the end cap 110 has a second groove 116 that penetrates the first surface 112 and surrounds the outer periphery of the explosion-proof valve subassembly 160; the second interface 170 includes a connected second flange portion 171 and a second interface portion 172, the second flange portion 171 surrounds the outer periphery of the second interface portion 172, the second flange portion 171 is disposed in the second groove 116, and the second interface portion 172 is used to connect to an external collection pipe; along the thickness direction of the end cap 110, the height of the second interface portion 172 is W3, then the end cap assembly 100 satisfies the relationship: W3≥W1+3mm.

[0191] Specifically, the value of W3 can be, but is not limited to, W1+3mm, 1.1×(W1+3mm), 1.3×(W1+3mm), 1.5×(W1+3mm), 1.6×(W1+3mm), 1.8×(W1+3mm), and 2×(W1+3mm).

[0192] Understandably, the second flange portion 171 and the second interface portion 172 are arranged sequentially along the thickness direction of the end cap 110.

[0193] Understandably, the second interface portion 172 forms a second channel 174 to facilitate the collection and transfer of fluid, and to discharge the fluid from the end cap assembly 100 through the external collection pipe.

[0194] In this embodiment, the second interface component 170 includes a connected second flange portion 171 and a second interface portion 172. The second flange portion 171 and the second interface portion 172 are arranged sequentially along the thickness direction of the end cap component 110. The second flange portion 171 is disposed in the second groove 116 and connected to the end cap component 110 to improve the sealing performance between the second interface component 170 and the end cap component 110, and to prevent fluid discharged from the explosion-proof valve subassembly 160 from overflowing from the gap between the second flange portion 171 and the end cap component 110. The second interface portion 172 facilitates the connection between the second interface component 170 and the external collection pipe to improve the connection stability between the second interface component 170 and the external collection pipe. When the end cap assembly 100 satisfies the relationship W3≥W1+3mm, the height of the second interface portion 172 is within a reasonable range, so that the second interface portion 172 can be stably connected to the external collection pipe, and the second channel 174 formed by the second interface portion 172 can accommodate the airflow ejected from the explosion-proof valve sub-assembly 160, preventing the airflow from returning to the second surface 113 side. Furthermore, when the explosion-proof valve sub-assembly 160 is folded relative to the end cap 110, the second interface portion 172 can provide space for the explosion-proof valve sub-assembly 160 to fold, avoiding affecting the folding of the explosion-proof valve sub-assembly 160, thus ensuring the function and role of the explosion-proof valve sub-assembly 160.

[0195] Optionally, the height W3 of the second interface portion 172 is in the range of 5mm≤W3≤60mm, so that the second interface portion 172 can provide space for the explosion-proof valve subassembly 160 to fold and be securely connected to the external collection pipe.

[0196] Specifically, the height W3 of the second interface portion 172 can be, but is not limited to, 5mm, 8mm, 10mm, 12mm, 15mm, 18mm, 20mm, 22mm, 25mm, 28mm, 30mm, 32mm, 35mm, 38mm, 40mm, 42mm, 45mm, 48mm, 50mm, 52mm, 55mm, 58mm, and 60mm.

[0197] In some embodiments, the outer periphery of the second interface portion 172 is provided with a protrusion structure 1721.

[0198] Understandably, the protrusion structure 1721 can be, but is not limited to, a thread, corrugation, sawtooth structure, etc.

[0199] In this embodiment, a protruding structure 1721 is provided on the outer periphery of the second interface portion 172. When the second interface portion 172 is connected to an external collection pipe, and the external collection pipe is sleeved on the outer periphery of the second interface portion 172, the protruding structure 1721 can increase the friction coefficient between the second interface portion 172 and the external collection pipe, preventing the external collection pipe from falling off the second interface portion 172. At the same time, it can improve the sealing performance between the second interface portion 172 and the external collection pipe, preventing fluid leakage from the gap between the second interface portion 172 and the external collection pipe.

[0200] Understandably, when the external collection pipe is fitted around the outer periphery of the second interface portion 172, the inner diameter of the external collection pipe is smaller than the outer diameter of the second interface portion 172, so as to achieve an interference fit between the second interface portion 172 and the external collection pipe and achieve an interference seal.

[0201] Understandably, when the protrusion structure 1721 is a one-way sawtooth structure, the external collection pipe is difficult to pull out after being sleeved on the outer periphery of the second interface portion 172, and the second interface portion 172 and the external collection pipe have good sealing performance.

[0202] Optionally, along the thickness direction of the end cap 110, the second interface portion 172 includes a first sub-portion 1722 and a second sub-portion 1723 connected together. The end of the first sub-portion 1722 opposite to the second sub-portion 1723 is connected to the second flange portion 171. The second sub-portion 1723 is provided with the protrusion structure 1721. The end cap assembly 100 also includes a fixing strap (not shown). When the external collection pipe is sleeved on the outer periphery of the second interface portion 172, the fixing strap is sleeved on the outer periphery of the external collection pipe, and the fixing strap is located on the outer periphery of the first sub-portion 1722.

[0203] Understandably, the radial dimension of the first sub-part 1722 is smaller than the radial dimension of the second sub-part 1723, and the radial dimension of the first sub-part 1722 is smaller than the radial dimension of the second flange part 171.

[0204] Understandably, the fixing strap can be, but is not limited to, cable ties, straps, etc.

[0205] In this embodiment, the first sub-part 1722 is located between the second sub-part 1723 and the second flange part 171, and the radial dimension of the first sub-part 1722 is smaller than the radial dimension of the second sub-part 1723 and the radial dimension of the second flange part 171. When the fixing band is sleeved on the outer periphery of the external collection pipe and located on the outer periphery of the first sub-part 1722, the second sub-part 1723 and the second flange part 171 can limit the fixing band to prevent the fixing band from moving along the thickness direction of the end cap 110, so that the fixing band can be stably set on the outer periphery of the first sub-part 1722, thereby having a better fixing effect on the external collection pipe and improving the sealing performance between the external collection pipe and the second interface part 170.

[0206] Please see Figure 25 and Figure 26 In some embodiments, the end cap 110 has a second groove 116 that penetrates the first surface 112 and surrounds the outer periphery of the explosion-proof valve subassembly 160; the second interface 170 includes a connected second flange portion 171, a connecting portion 173, and a second interface portion 172, the second flange portion 171 surrounds the outer periphery of the connecting portion 173, the second flange portion 171 is disposed in the second groove 116, and the second interface portion 172 is used to connect to an external collection pipe.

[0207] Understandably, the connecting portion 173 and the second interface portion 172 form the second channel 174 to facilitate the collection and transmission of fluid, and to discharge the fluid from the end cap assembly 100 through the external collection pipe.

[0208] In this embodiment, the second interface component 170 includes a connected second flange portion 171, a connecting portion 173, and a second interface portion 172. Along the thickness direction of the end cap component 110, the second flange portion 171, the connecting portion 173, and the second interface portion 172 are arranged sequentially. The second flange portion 171 is disposed in the second groove 116 and connected to the end cap component 110 to improve the sealing performance between the second interface component 170 and the end cap component 110, preventing fluid discharged from the explosion-proof valve subassembly 160 from overflowing from the gap between the second flange portion 171 and the end cap component 110. The connecting portion 173 increases the length of the second channel 174 so that when fluid flows from the explosion-proof valve subassembly 160 to the first surface 112 side, the second channel 174 can accommodate the ejected airflow, preventing the airflow from returning to the second surface 113 side through the explosion-proof hole 115. The second interface portion 172 facilitates the connection between the second interface component 170 and the external collection pipe, thereby improving the connection stability between the second interface component 170 and the external collection pipe.

[0209] Optionally, in some embodiments, the second interface portion 172 is provided with external threads to achieve a threaded connection with an external collection pipe.

[0210] Alternatively, in other embodiments, the second interface portion 172 is provided with internal threads to achieve a threaded connection with an external collection pipe.

[0211] In some embodiments, the connecting portion 173 includes a first connecting sub-portion 1731 and a second connecting sub-portion 1732 connected together. The end of the first connecting sub-portion 1731 opposite to the second connecting sub-portion 1732 is connected to the second flange portion 171, and the end of the second connecting sub-portion 1732 opposite to the first connecting sub-portion 1731 is connected to the second interface portion 172. Both the first connecting sub-portion 1731 and the second interface portion 172 extend along the thickness direction of the end cap 110, and the radial dimension of the first connecting sub-portion 1731 is larger than the radial dimension of the second interface portion 172.

[0212] Understandably, the second connecting part 1732 and the second interface part 172 form a structure similar to a "pot-shaped connector", and the first connecting part 1731 and the second flange part 171 form a structure similar to a "pot body".

[0213] Understandably, along the thickness direction of the end cap 110, the second flange portion 171, the first connecting sub-portion 1731, the second connecting sub-portion 1732, and the second interface portion 172 are arranged sequentially.

[0214] In this embodiment, the first connecting part 1731 is located closer to the second flange part 171 than the second connecting part 1732, and the first connecting part 1731 extends along the thickness direction of the end cap 110. Therefore, the outline of the first connecting part 1731 is similar to the outline of the explosion-proof valve sub-assembly 160. When the explosion-proof valve sub-assembly 160 is folded relative to the end cap 110, the inner wall of the first connecting part 1731 can be prevented from interfering with the explosion-proof valve sub-assembly 160, thus ensuring the function and role of the explosion-proof valve sub-assembly 160. Furthermore, the second interface portion 172 extends along the thickness direction of the end cap 110. The radial dimension of the first connecting sub-portion 1731 is larger than the radial dimension of the second interface portion 172. The opposite ends of the second connecting sub-portion 1732 are respectively connected to the first connecting sub-portion 1731 and the second interface portion 172 to achieve the connection between the first connecting sub-portion 1731 and the second interface portion 172, and to avoid the second interface portion 172 having an excessively large radial dimension, which would affect the assembly with the external collection pipe. Moreover, compared to the solution of setting a protruding structure 1721, such as a thread or serrated structure, on the first connecting sub-portion 1731 with a similar outline to the explosion-proof valve sub-assembly 160, this solution directly sets the thread on the outer periphery of the second connector portion with a circular structure, which helps to simplify the manufacturing difficulty of the second interface component 170 and reduce the manufacturing cost of the second interface component 170.

[0215] In some embodiments, if the height of the first connecting sub-part 1731 along the thickness direction of the end cap 110 is W4, then the end cap assembly 100 satisfies the relationship: W4≥W1+4mm.

[0216] Specifically, the value of W4 can be, but is not limited to, W1+4mm, 1.1×(W1+4mm), 1.3×(W1+4mm), 1.5×(W1+4mm), 1.6×(W1+4mm), 1.8×(W1+4mm), and 2×(W1+4mm).

[0217] In this embodiment, when the end cap assembly 100 satisfies the relationship W4≥W1+4mm, the height of the first connecting part 1731 is within a reasonable range. On the one hand, when the explosion-proof valve sub-assembly 160 is folded relative to the end cap 110, the first connecting part 1731 can provide space for the explosion-proof valve sub-assembly 160 to fold, avoiding affecting the folding of the explosion-proof valve sub-assembly 160 and ensuring the function and role of the explosion-proof valve sub-assembly 160. On the other hand, it is beneficial to increase the length of the second channel 174 formed by the connecting part 173 and the second interface part 172. The second channel 174 can accommodate the airflow ejected from the explosion-proof valve sub-assembly 160, preventing the airflow from returning to the second surface 113 side and improving the safety and reliability of the end cap assembly 100.

[0218] Optionally, the height W4 of the first connecting part 1731 is in the range of 5mm≤W4≤60mm, so that the first connecting part 1731 can provide space for the explosion-proof valve subassembly 160 to fold.

[0219] Specifically, the height W4 of the first connecting sub-part 1731 can be, but is not limited to, 5mm, 10mm, 15mm, 18mm, 20mm, 22mm, 25mm, 28mm, 30mm, 35mm, 38mm, 40mm, 42mm, 45mm, 48mm, 50mm, 52mm, 55mm, 58mm and 60mm.

[0220] Optionally, in some embodiments, the end cap assembly 100 includes the one-way valve subassembly 130, and the first interface element 140 is disposed around the one-way valve subassembly 130. In other embodiments, the end cap assembly 100 includes the explosion-proof valve subassembly 160, and the second interface element 170 is disposed around the explosion-proof valve subassembly 160. In still other embodiments, the end cap assembly 100 includes the one-way valve subassembly 130, the first interface element 140 disposed around the one-way valve subassembly 130, the explosion-proof valve subassembly 160, and the second interface element 170 disposed around the explosion-proof valve subassembly 160.

[0221] In this embodiment, the end cap assembly 100 is located on one side of the housing 210 and connected to the housing 210. The end cap assembly 100 closes the opening of the receiving cavity 211, so that the receiving cavity 211 forms a sealed chamber. When the gas pressure inside the energy storage device 200 increases, it can be depressurized through the one-way valve subassembly 130 and / or the explosion-proof valve subassembly 160, so that the fluid located on the second surface 113 side of the end cap 110 can be discharged to the first surface 112 side, and connected to an external collection pipe through the first interface 140 and / or the second interface 170, so as to prevent flammable and explosive gases in the ejected fluid from accumulating on the first surface 112 side and igniting an explosion. The energy storage device 200 has good safety performance.

[0222] Optionally, the energy storage device 200 further includes an electrolyte located within the receiving cavity 211 to wet at least a portion of the electrode assembly 220. The fluid in this application terminology may include the electrolyte. When the electrolyte is carried by an airflow to the first surface 112 side, if the electrolyte falls directly onto the end cap 110, it may corrode the end cap 110 and affect its service life. Collecting a portion of the ejected electrolyte through an external collection pipe can prevent the electrolyte from affecting the end cap 110, improve the performance of the end cap assembly 100, and extend the service life of the energy storage device 200.

[0223] Please see Figure 29 and Figure 30 This application provides an electrical device 300, which includes: a device body 310 and an energy storage device 200 provided in this application, wherein the energy storage device 200 supplies power to the device body 310.

[0224] Understandably, the energy storage device 200 is electrically connected to the electrical equipment 300.

[0225] In this embodiment, the electrical device 300 includes the energy storage device 200 provided in this application, which has good safety and reliability. When the energy storage device 200 is applied to the electrical device 300, it can provide stable power to the device body 310, which is beneficial to improving the user experience.

[0226] Optionally, the electrical device 300 in this application embodiment can be, but is not limited to, portable electronic devices such as mobile phones, tablets, laptops, desktop computers, smart bracelets, smartwatches, e-readers, and game consoles. It can also be a vehicle such as a car, truck, sedan, van, freight train, high-speed train, or electric vehicle. Furthermore, it can be various household appliances. Figure 30 The electrical equipment 300 in this embodiment is an energy storage battery cabinet.

[0227] It is understood that the electrical equipment described in this embodiment is merely one form of electrical equipment used in the energy storage device, and should not be construed as a limitation on the electrical equipment provided in this application, nor should it be construed as a limitation on the electrical equipment provided in various embodiments of this application.

[0228] In this application, the terms "embodiment" and "implementation" mean that a specific feature, structure, or characteristic described in connection with an embodiment can be included in at least one embodiment of this application. The appearance of these phrases in various locations throughout the specification does not necessarily refer to the same embodiment, nor are they independent or alternative embodiments mutually exclusive with other embodiments. Those skilled in the art will understand, explicitly and implicitly, that the embodiments described in this application can be combined with other embodiments. Furthermore, it should be understood that the features, structures, or characteristics described in the various embodiments of this application can be arbitrarily combined to form another embodiment that does not depart from the spirit and scope of the technical solution of this application, provided there is no contradiction between them.

[0229] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to the above preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of this application should not depart from the spirit and scope of the technical solutions of this application.

Claims

1. An energy storage device (200), characterized in that, The energy storage device (200) includes: The housing (210) has a receiving cavity (211); An end cap assembly (100) is used to seal the receiving cavity (211). The end cap assembly (100) includes an end cap member (110), a lower seal member (180), and a one-way valve assembly (120). The end cap member (110) and the lower seal member (180) are located on the same side of the housing (210). The housing (210), the lower seal member (180), and the end cap member (110) are arranged sequentially. The end cap (110) has a mounting groove (111), an air inlet (117), a first surface (112) and a second surface (113) disposed opposite to each other along the thickness direction of the end cap (110), the second surface (113) facing the receiving cavity (211), the mounting groove (111) being recessed in the first surface (112), and the air inlet (117) penetrating the second surface (113) and penetrating the bottom wall of the mounting groove (111); the lower seal (180) has a through hole (181), the through hole (181) penetrating the two opposite surfaces of the lower seal (180) along the thickness direction, the through hole (181) being... The hole (181) is connected to the receiving cavity (211), the air inlet (117) and the mounting groove (111) respectively; the one-way valve assembly (120) includes a one-way valve sub-assembly (130) and a first interface (140). The one-way valve sub-assembly (130) is installed in the mounting groove (111) and is used to allow fluid to flow from the second surface (113) side to the first surface (112) side; the first interface (140) is located on the first surface (112) side of the end cap (110) and is connected to the one-way valve sub-assembly (130). The first interface (140) is used to connect to an external collection pipe.

2. The energy storage device (200) according to claim 1, characterized in that, The end cap (110) also has a first groove (114) that penetrates the first surface (112) and surrounds the outer periphery of the one-way valve subassembly (130). The first interface (140) includes a first flange (141) and a first interface (142) connected together. The first flange (141) is disposed in the first groove (114) and is fixedly connected to the side wall of the first groove (114). Along the thickness direction of the end cap (110), the depth of the first groove (114) is h1, and the thickness of the first flange (141) is h2. Then the end cap assembly (100) satisfies the relationship: h1-h2≥0.3mm.

3. The energy storage device (200) according to claim 2, characterized in that, Along the thickness direction of the end cap (110), the thickness of the end cap (110) is h3, then the end cap assembly (100) satisfies the relationship: 0.2×h3≤h1≤0.8×h3.

4. The energy storage device (200) according to claim 2, characterized in that, The first interface (140) satisfies one of the following conditions: The outer periphery of the first interface portion (142) is provided with external threads so that the first interface portion (142) can be threadedly connected to the external collection pipe; The first interface portion (142) has an internal thread on its inner side so that the first interface portion (142) can be threadedly connected to the external collection pipe.

5. The energy storage device (200) according to claim 2, characterized in that, The outer periphery of the first interface part (142) is provided with an external thread. The inner diameter of the first interface part (142) is D1, and the outer diameter of the first interface part (142) is D2. Then the first interface part (140) satisfies the relationship: D2-D1≥0.8×h2.

6. The energy storage device (200) according to claim 5, characterized in that, Along the thickness direction of the end cap (110), the height of the first interface portion (142) is h4, and the end cap assembly (100) satisfies the relationship: 0.5×D2≤h4≤1.5×D2.

7. The energy storage device (200) according to claim 2, characterized in that, The one-way valve subassembly (130) includes a sealing ring (131), a sealing plate (132), a spring plate (133), and a welding plate (134). Along the thickness direction of the end cap (110), the sealing ring (131), the sealing plate (132), the spring plate (133), and the welding plate (134) are sequentially disposed in the mounting groove (111); the first interface member (140) is connected to the welding plate (134).

8. The energy storage device (200) according to claim 7, characterized in that, The mounting groove (111) includes a first sub-groove (1111) and a second sub-groove (1112) that are connected to each other. The first sub-groove (1111) and the second sub-groove (1112) are coaxially arranged. The first sub-groove (1111) is recessed in the first surface (112). The air inlet (117) penetrates the bottom wall of the second sub-groove (1112). The radial dimension of the first sub-groove (1111) is greater than the radial dimension of the second sub-groove (1112). The sealing ring (131) and the sealing piece (132) are located in the second sub-groove (1112). The spring piece (133) is engaged with the welding piece (134). The welding piece (134) and the first interface piece (140) are located in the first sub-groove (1111).

9. The energy storage device (200) according to claim 7, characterized in that, The welding piece (134) has a snap-fit ​​hole (1341). The spring sheet (133) includes an elastic part (1331), a through part (1332), and a mating part (1333) that are bent and connected in sequence. The elastic part (1331) and the mating part (1333) are bent toward the same side relative to the through part (1332). The through part (1332) passes through the snap hole (1341). The elastic part (1331) is located on the side of the welding piece (134) facing the sealing piece (132). The elastic part (1331) has a vent hole (1334). The vent hole (1334) passes through two opposing surfaces of the elastic part (1331) along the thickness direction. The mating part (1333) is located on the side of the welding piece (134) away from the sealing piece (132).

10. The energy storage device (200) according to claim 9, characterized in that, The inner diameter of the first interface part (142) is D1, and the maximum radial dimension of the mating part (1333) is D3 along the radial direction of the mating part (1333). Then the end cap assembly (100) satisfies the relationship: 2mm≤D1-D3≤6mm.

11. The energy storage device (200) according to claim 9, characterized in that, The inner diameter of the through part (1332) is D4, and the thickness of the spring piece (133) is T. Then the end cap assembly (100) satisfies the relationship: 5T≤D3-D4≤10T.

12. The energy storage device (200) according to any one of claims 1 to 11, characterized in that, The end cap (110) also has an explosion-proof hole (115) that penetrates the first surface (112) and the second surface (113). The end cap assembly (100) further includes an explosion-proof valve assembly (150), which includes an explosion-proof valve sub-assembly (160) and a second interface (170). The explosion-proof valve sub-assembly (160) is mounted on the end cap assembly (110) and covers the explosion-proof hole (115). The second interface (170) is located on the first surface (112) side and communicates with the explosion-proof valve sub-assembly (160). The second interface (170) is used to connect to an external collection pipe.

13. The energy storage device (200) according to claim 12, characterized in that, Along the length of the end cap (110), the width of the explosion-proof valve sub-assembly (160) is W1, and the inner diameter of the second interface (170) is W2. Then the end cap assembly (100) satisfies the relationship: W2≥2×(W1+3mm).

14. The energy storage device (200) according to claim 13, characterized in that, The end cap (110) has a second groove (116) that penetrates the first surface (112) and is arranged around the outer periphery of the explosion-proof valve subassembly (160); The second interface component (170) includes a connected second flange portion (171) and a second interface portion (172). The second flange portion (171) is arranged around the outer periphery of the second interface portion (172). The second flange portion (171) is disposed in the second groove (116). The second interface portion (172) is used to connect to an external collection pipe. Along the thickness direction of the end cap component (110), the height of the second interface portion (172) is W3. Then the end cap assembly (100) satisfies the relationship: W3≥W1+3mm.

15. The energy storage device (200) according to claim 14, characterized in that, The second interface portion (172) has a protruding structure (1721) on its outer periphery.

16. The energy storage device (200) according to claim 13, characterized in that, The end cap (110) has a second groove (116) that penetrates the first surface (112) and is arranged around the outer periphery of the explosion-proof valve subassembly (160); The second interface component (170) includes a connected second flange portion (171), a connecting portion (173) and a second interface portion (172). The second flange portion (171) is disposed around the outer periphery of the connecting portion (173) and is disposed in the second groove (116). The second interface portion (172) is used to connect an external collection pipe.

17. The energy storage device (200) according to claim 16, characterized in that, The connecting part (173) includes a first connecting sub-part (1731) and a second connecting sub-part (1732) connected together. The end of the first connecting sub-part (1731) opposite to the second connecting sub-part (1732) is connected to the second flange part (171), and the end of the second connecting sub-part (1732) opposite to the first connecting sub-part (1731) is connected to the second interface part (172). Both the first connecting sub-part (1731) and the second interface part (172) extend along the thickness direction of the end cap (110), and the radial dimension of the first connecting sub-part (1731) is greater than the radial dimension of the second interface part (172).

18. The energy storage device (200) according to claim 17, characterized in that, If the height of the first connecting part (1731) is W4 along the thickness direction of the end cap (110), then the end cap assembly (100) satisfies the relationship: W4≥W1+4mm.

19. An electrical appliance (300), characterized in that, The electrical equipment (300) includes: Equipment body (310); and The energy storage device (200) according to any one of claims 1 to 18, wherein the energy storage device (200) supplies power to the device body (310).

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