End cap assembly, energy storage device, and electrical device

Abstract

The application provides an end cover assembly, an energy storage device and an electric equipment, which are used for ensuring the exhaust smoothness when the energy storage device is in thermal runaway and improving the safety and reliability of the energy storage device. In the end cover assembly, the explosion-proof hole of the end cover penetrates the first surface and the second surface of the end cover, the explosion-proof valve is installed on the end cover and covers the explosion-proof hole, the supporting piece and the limiting piece are located on the side of the second surface away from the first surface, at least two supporting pieces are respectively located on the opposite sides of the explosion-proof hole and are arranged at intervals from the explosion-proof hole along the length direction of the end cover assembly, the first side surface of the supporting piece is close to the explosion-proof valve, the second side surface of the supporting piece is arranged away from the first side surface, the supporting piece is provided with an exhaust passage, the exhaust passage penetrates the first side surface and the second side surface, the first limiting part of the limiting piece is located between the supporting piece and the explosion-proof hole, is arranged at intervals from the explosion-proof hole and is fixedly installed on the second surface, and the projection of the first limiting part on the plane where the first side surface is located overlaps at least part of the first side surface.

Description

Technical Field

[0001] This application relates to the field of energy storage technology, and in particular to an end cap assembly, an energy storage device, and an electrical appliance. Background Technology

[0002] A rechargeable battery, also known as a secondary battery or accumulator, is a battery that can be recharged after discharge to reactivate its active materials and continue to be used. Its recyclable nature has made it a primary power source for electrical devices. As the demand for rechargeable batteries increases, higher requirements are being placed on their energy density, reliability, and cost. When a rechargeable battery experiences thermal runaway, the lower insulation component softens or even melts at high temperatures and is carried out of the explosion-proof valve by the gas flow. The battery cell assembly floats up and blocks the venting channel between the end cap and the cell assembly, leading to poor venting. This sudden increase in internal pressure can cause the casing to crack, reducing the battery's safety and reliability. Summary of the Invention

[0003] This application provides an end cap assembly, an energy storage device, and an electrical device to ensure smooth venting during thermal runaway of the energy storage device and improve the safety and reliability of the energy storage device.

[0004] In a first aspect, this application provides an end cap assembly for use in an energy storage device. The end cap assembly includes an end cap, an explosion-proof valve, multiple support members, and multiple limiting members. The end cap has a first surface and a second surface, which are disposed opposite to each other along the thickness direction of the end cap assembly. The end cap is provided with an explosion-proof hole that penetrates the first surface and the second surface. The explosion-proof valve is installed on the end cap and covers the explosion-proof hole. The multiple support members and the multiple limiting members are all located on the side of the second surface away from the first surface. Along the length direction of the end cap assembly, at least two support members are located on opposite sides of the explosion-proof hole and are spaced apart from the explosion-proof hole. Each support member has a first side. The end cap assembly has a first side and a second side. Along the length of the end cap assembly, the first side is the surface of the support member near the explosion-proof valve, and the second side is opposite to the first side. Each support member has an exhaust channel that passes through the first side and the second side. Each limiting member includes a first limiting portion. Along the length of the end cap assembly, the first limiting portion is located between a support member and the explosion-proof hole, and is spaced apart from the explosion-proof hole. It is fixedly installed on the second surface. Along the length of the end cap assembly, the projection of the first limiting portion on the plane of the first side overlaps with at least a portion of the first side to restrict the movement of the support member toward the explosion-proof valve.

[0005] When the energy storage device used in the end cap assembly experiences thermal runaway, the support member will move toward the explosion-proof valve under the action of airflow. The first limiting part of the limiting member can restrict the movement of the support member toward the explosion-proof valve, ensuring that the support member can always abut against the cell assembly, so as to prevent the cell assembly from floating up and blocking the exhaust channel between the end cap and the cell assembly, ensuring the smooth exhaust of the energy storage device and improving the safety and reliability of the energy storage device.

[0006] The assembly comprises multiple supporting members and multiple limiting members. Each supporting member includes a first supporting member and a second supporting member. Along the length of the end cap assembly, the first supporting member and the second supporting member are located on opposite sides of the explosion-proof hole. Each limiting member includes multiple first limiting members and multiple second limiting members. Along the width of the end cap assembly, the multiple first limiting members are spaced apart to collectively restrict the movement of the first supporting member toward the explosion-proof valve, ensuring the reliability of the limiting position on the first supporting member. The first limiting portion of each first limiting member is located between the first supporting member and the explosion-proof hole. Along the width of the end cap assembly, the multiple second limiting members are spaced apart. The first limiting portion of each second limiting member is located between the second supporting member and the explosion-proof hole, collectively restricting the movement of the second supporting member toward the explosion-proof valve, ensuring the reliability of the limiting position on the second supporting member.

[0007] When the energy storage device using the end cap assembly experiences thermal runaway, both the first support member and the second support member will move towards the explosion-proof valve under the action of airflow. The first limiting part of the first limiting member can restrict the movement of the first support member towards the explosion-proof valve, and the first limiting part of the second limiting member can restrict the movement of the second support member towards the explosion-proof valve. This ensures that the first support member and the second support member can always abut against the cell assembly, so as to prevent the cell assembly from floating up and blocking the exhaust channel between the end cap and the cell assembly, ensuring the smooth exhaust of the energy storage device and improving the safety and reliability of the energy storage device.

[0008] Wherein, along the length direction of the end cap assembly, the projection of the first limiting portion on the plane where the first side side is located overlaps with at least a portion of the exhaust channel; Each of the aforementioned limiting members further includes a second limiting part, which is fixedly connected to the side of the first limiting part facing the support member and extends into the exhaust channel to improve the assembly stability of the support member in the end cap assembly, prevent the support member from shifting under the action of airflow when the energy storage device experiences thermal runaway, and ensure that the support member always remains in its original position. The support member can always abut against the cell assembly to prevent the cell assembly from floating up and blocking the exhaust channel between the end cap and the cell assembly, ensuring the smooth exhaust of the energy storage device and improving the safety and reliability of the energy storage device.

[0009] Wherein, along the length direction of the end cap assembly, the projection of the first limiting portion on the plane where the first side side is located overlaps with at least a portion of the exhaust channel; Each of the limiting members is spaced apart from the support member and also includes a second limiting part, which is fixedly connected to the side of the first limiting part facing the support member. The projection of the second limiting part on the plane of the first side overlaps with at least a portion of the exhaust channel.

[0010] When the energy storage device to which the end cap assembly is used experiences thermal runaway, the support member will move toward the explosion-proof valve under the action of airflow. The first limiting part of the limiting member can restrict the movement of the support member toward the explosion-proof valve on the movement path of the support member, ensuring that the support member can always abut against the cell assembly, so as to prevent the cell assembly from floating up and blocking the exhaust channel between the end cap and the cell assembly, ensuring the smooth exhaust of the energy storage device and improving the safety and reliability of the energy storage device.

[0011] Wherein, along the length direction of the end cap assembly, the projection of the second limiting portion on the plane where the first side is located overlaps with at least a portion of the first side, and together with the first limiting portion, restricts the movement of the support member toward the explosion-proof valve.

[0012] Wherein, along the length direction of the end cap assembly, the projection of the first limiting part on the plane where the first side is located is misaligned with at least part of the exhaust channel, so as to reduce the influence of the limiting member on the exhaust channel and avoid the limiting member affecting the exhaust efficiency of the exhaust channel.

[0013] The end cap assembly further includes a lower insulating member located on the side of the second surface opposite to the first surface, and the lower insulating member has a third surface facing the end cap. The lower insulating member is provided with a groove, and the opening of the groove is located on the third surface; The support member is housed in the groove and can be wrapped by the lower insulating member, which can effectively prevent the support member from contacting the battery cell assembly and prevent the support member from being electrically connected to the battery cell assembly, thus avoiding short circuit between the positive and negative tabs of the battery cell assembly.

[0014] The lower insulating member further has a fourth surface, which is disposed opposite to the third surface; The groove has a first groove sidewall surface near the explosion-proof valve; The lower insulating member has a protrusion, which is located on the fourth surface and corresponds to the groove. The protrusion has a third side surface near the explosion-proof valve, which is opposite to the side wall of the first groove. The lower insulating component is provided with a first vent hole, which penetrates the first groove sidewall and the third side and is connected to the vent channel, thereby reducing the volume of the lower insulating component and saving the cost of the lower insulating component.

[0015] The groove also has a second groove sidewall, which is disposed opposite to the first groove sidewall. The protrusion also has a fourth side surface, which is disposed opposite to the third side surface and opposite to the side wall surface of the second groove. The lower insulating component is also provided with a second vent hole, which penetrates the side wall of the second groove and the fourth side and is connected to the vent channel. This not only reduces the volume of the lower insulating component and saves on its cost, but also improves the efficiency of airflow discharge from the explosion-proof hole when the energy storage device malfunctions.

[0016] At least a portion of the limiting member is housed in the groove and can be wrapped by the lower insulating member, which can effectively prevent the limiting member from contacting the cell assembly and prevent the limiting member from being electrically connected to the cell assembly, thus avoiding short circuit between the positive and negative tabs of the cell assembly.

[0017] The lower insulating member further has a fourth surface, which is disposed opposite to the third surface. The lower insulating member is provided with a clearance hole, which is spaced apart from the groove and penetrates the third surface and the fourth surface. The limiting member is spaced apart from the supporting member and passes through the clearance hole.

[0018] When the energy storage device to which the end cap assembly is used experiences thermal runaway, the support member will move toward the explosion-proof valve under the action of airflow. The first limiting part of the limiting member can restrict the movement of the support member toward the explosion-proof valve on the movement path of the support member, ensuring that the support member can always abut against the cell assembly, so as to prevent the cell assembly from floating up and blocking the exhaust channel between the end cap and the cell assembly, ensuring the smooth exhaust of the energy storage device and improving the safety and reliability of the energy storage device.

[0019] The protrusion has a protruding surface that is opposite to the fourth surface, and the limiting member has a fifth surface that is opposite to the fourth surface. The fifth surface is located on the side of the protruding surface facing the fourth surface, so as to avoid the limiting member from contacting the cell assembly and to avoid the limiting member from being electrically connected to the cell assembly, which would cause the positive and negative tabs of the cell assembly to conduct and short-circuit.

[0020] The end cap assembly further includes a lower insulating member, which is located on the side of the second surface away from the second surface. The lower insulating member has a third surface and a fourth surface. The third surface is the surface of the lower insulating member facing the end cap, and the fourth surface is disposed opposite to the third surface. The lower insulating member is provided with a groove, which penetrates the third surface and the fourth surface; The support member passes through the groove.

[0021] When the energy storage device used in the end cap assembly experiences thermal runaway, the support member will move toward the explosion-proof valve under the action of airflow. The first limiting part of the limiting member can restrict the movement of the support member toward the explosion-proof valve, ensuring that the support member can always abut against the cell assembly, so as to prevent the cell assembly from floating up and blocking the exhaust channel between the end cap and the cell assembly, ensuring the smooth exhaust of the energy storage device and improving the safety and reliability of the energy storage device.

[0022] The support member also has a support surface that faces away from the end cap; The end cap assembly further includes an insulating layer disposed on the support surface to isolate the cell assembly and the support member, prevent the support member from contacting the cell assembly, and prevent the support member from being electrically connected to the cell assembly, which would cause a short circuit between the positive and negative tabs of the cell assembly.

[0023] The exhaust channels are multiple and spaced apart along the width of the end cap assembly to improve the exhaust efficiency of the support member.

[0024] Wherein, along the width direction of the end cap assembly, the width of the end cap is W, and the number of exhaust channels is F, 6mm≤W / F≤20mm. This not only avoids W / F being too small, causing the support to occupy too much cross section and resulting in insufficient cross section of the exhaust channels, but also avoids W / F being too large, causing the exhaust channels to be too wide and have a large span, which would result in the exhaust channels being squeezed and deformed by the cell assembly, causing the exhaust channels to shrink or even flatten and lose their exhaust function.

[0025] The first limiting part is welded to the second surface. The material of the limiting part is the same as the material of the end cap, or the material of the limiting part is the same as the main material of the end cap, so as to ensure the welding reliability of the limiting part and the end cap and avoid the explosion point caused by the different welding melting points of the limiting part and the end cap.

[0026] Secondly, this application provides an energy storage device, including a housing, a battery cell assembly, and any of the end cap assemblies described above. The housing has a receiving cavity and an opening. The receiving cavity is located inside the housing, and the opening communicates with the receiving cavity. The battery cell assembly is received in the receiving cavity. The end cap assembly is installed on the housing, closes the opening, and is electrically connected to the battery cell assembly.

[0027] When the energy storage device experiences thermal runaway, the support member will move toward the explosion-proof valve under the action of airflow. The first limiting part of the limiting member can restrict the movement of the support member toward the explosion-proof valve, ensuring that the support member can always abut against the cell assembly, so as to prevent the cell assembly from floating up and blocking the exhaust channel between the end cover and the cell assembly, ensuring the smooth exhaust of the energy storage device and improving the safety and reliability of the energy storage device.

[0028] Thirdly, this application provides an electrical device, including the energy storage device described above, which supplies power to the electrical device.

[0029] When the energy storage device used in the end cap assembly experiences thermal runaway, the support member will move toward the explosion-proof valve under the action of airflow. The first limiting part of the limiting member can restrict the movement of the support member toward the explosion-proof valve, ensuring that the support member can always abut against the cell assembly, so as to prevent the cell assembly from floating up and blocking the exhaust channel between the end cap and the cell assembly, ensuring the smooth exhaust of the energy storage device and improving the safety and reliability of the energy storage device. Attached Figure Description

[0030] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be described below.

[0031] Figure 1aThis is a schematic diagram of the structure of the first energy storage system according to an embodiment of this application; Figure 1b This is a schematic diagram of the structure of a second type of energy storage system according to an embodiment of this application; Figure 2 This is a schematic diagram of the energy storage device provided in this application; Figure 3 yes Figure 2 A schematic diagram of the end cap assembly in the energy storage device shown in the first embodiment; Figure 4 yes Figure 3 The exploded structural diagram of the end cap assembly shown; Figure 5 yes Figure 4 The diagram shows the structure of the end cap and lower insulator in the end cap assembly at another angle. Figure 6 yes Figure 4 The diagram shows the structure of the support and limiting components in the end cap assembly. Figure 7 yes Figure 3 A partial structural schematic diagram of the end cap assembly shown; Figure 8 yes Figure 2 A schematic diagram of the end cap assembly in the energy storage device shown in the second embodiment; Figure 9 yes Figure 8 The diagram shows the structure of the lower insulating component in the end cap assembly. Figure 10 yes Figure 2 A schematic diagram of the end cap assembly in the energy storage device shown in the third embodiment; Figure 11 yes Figure 10 The diagram shows the structure of the lower insulating component in the end cap assembly. Figure 12 yes Figure 10 A partial structural schematic diagram of the end cap assembly shown; Figure 13 yes Figure 2 A schematic diagram of the end cap assembly in the energy storage device shown in the fourth embodiment; Figure 14 yes Figure 13 The diagram shows the structure of the lower insulating component in the end cap assembly. Figure 15 yes Figure 13 A partial structural schematic diagram of the end cap assembly shown; Figure 16 yes Figure 4 An exploded view of the pole post assembly in the end cap assembly shown. Figure 17 yes Figure 3 The diagram shows a cross-sectional view of the end cap assembly after it has been cut open at point II.

[0032] The names corresponding to the labels in the figure are: Energy storage system 1, high-voltage cable 2, first power conversion device 3, second power conversion device 4, energy storage device 5, photovoltaic-energy storage-charging station 6, automobile 7, housing 10, end cap assembly 20, end cap 21, explosion-proof valve 22, protective plate 23, lower insulating component 24, support component 25, limiting component 26, pole post assembly 27, first support component 25a, second support component 25b, first limiting component 26a, second limiting component 26b, first pole post assembly 27a, second pole post assembly 27b, first surface 211, second surface 212, explosion-proof hole 213, first pole post hole 214, third surface 241, fourth surface 242, explosion-proof fence 243, protrusion 244, protruding surface 2441, third side surface 2442, fourth side surface 2443, first protrusion 244a, second protrusion 244b, second pole hole 245, groove 246, first vent hole 247, first groove side wall 2461, second groove side wall 2462, first groove 246a, second groove 246b, first sub-insulator 24a, second sub-insulator 24b, first side 251, second side 252, support surface 253, vent channel 254, first channel wall 255, second channel wall 256, first limiting part 261, second limiting part 262, insulating layer 28, second vent hole 248, clearance hole 249, first clearance hole 249a, second clearance hole 249b, fifth surface 263, upper insulating part 271, pole 272, pressure block 273, sealing part 274, third pole hole 2711. Detailed Implementation

[0033] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0034] 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. 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.

[0035] Taking electrochemical energy storage as an example, this solution provides an energy storage device for use in energy storage systems. The energy storage device is equipped with a set of chemical batteries, which mainly use the chemical elements in the batteries as energy storage media. The charging and discharging process is accompanied by the chemical reaction or change of the energy storage media. Simply put, the electrical energy generated by wind and solar energy is stored in the chemical batteries. When the use of external electrical energy reaches its peak, the stored electricity is released for use, or transferred to places with a shortage of electricity for use.

[0036] Current energy storage applications are quite widespread, including generation-side energy storage, grid-side energy storage, and consumption-side energy storage. The corresponding types of energy storage devices include: (1) Large-scale energy storage power stations 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. (2) Energy storage containers applied on the grid side mainly function as peak shaving, frequency regulation and relief of grid congestion. In terms of peak shaving, they can realize peak shaving and valley filling of electricity load, that is, charging the energy storage battery when the electricity load is low and releasing the stored electricity during the peak electricity load period, thereby achieving a balance between power production and consumption. (3) Small energy storage cabinets applied to the electricity consumption side mainly function as self-consumption of electricity, peak-valley price arbitrage, capacity cost management, and improvement of power supply reliability. Depending on the application scenario, electricity consumption side energy storage can be divided into industrial and commercial energy storage cabinets, household energy storage devices, energy storage charging piles, etc., which are generally used in conjunction with distributed photovoltaics. Industrial and commercial users can use energy storage for peak-valley price arbitrage and capacity cost management. In the electricity market implementing peak-valley pricing, by charging the energy storage system when the electricity price is low and discharging the energy storage system when the electricity price is high, peak-valley price arbitrage can be achieved, reducing electricity costs. In addition, industrial enterprises subject to two-part tariffs can use energy storage systems to store energy during off-peak hours and discharge during peak loads, thereby reducing peak power and the maximum demand declared, achieving the goal of reducing capacity 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.

[0037] In some embodiments, see Figure 1a , Figure 1a This is a schematic diagram of the structure of the first type of energy storage system 1 according to an embodiment of this application, and this application Figure 1a The embodiments are illustrated using a shared energy storage scenario on the generation / distribution side as an example. The energy storage device 5 of this application is not limited to the energy storage scenario on the generation / distribution side.

[0038] This application provides a first type of energy storage system 1, which includes: a high-voltage cable 2, a first power conversion device 3, a second power conversion device 4, and an energy storage device 5 provided in this application. In some embodiments of the power generation scenario, the second power conversion device 4 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 5 through grid connection. The energy storage device 5 is connected to the high-voltage cable 2 and outputs smooth electricity to supply the power consumption side of the distribution network, realizing peak shaving and frequency regulation, and stable grid operation; or, the wind power conversion device initially... Finally, it connects to high-voltage cable 2. 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 energy storage device 5 to reduce wind and solar curtailment rates 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 energy storage device 5 together with high-voltage cable 2 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.

[0039] In some embodiments on the distribution network side, the first power conversion device 3 can be a photovoltaic power conversion device, and the energy storage device 5 is connected to the high-voltage cable 2 and installed downstream of the high-voltage cable 2 between the user load. The power output of the photovoltaic power conversion device is stored in the energy storage device 5, 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 blockage when the high-voltage cable 2 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.

[0040] Optionally, the first power conversion device may include, but is not limited to, a wind power conversion device, and the second power conversion device may include, but is not limited to, a photovoltaic power conversion device. The first power conversion device 3 and the second power conversion device 4 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy, and mechanical energy into electrical energy.

[0041] Optionally, the energy storage device 5 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.

[0042] Optionally, the energy storage device 5 may include, but is not limited to, a single battery cell, or a battery module, battery pack, battery cluster, power bank, energy storage cabinet / container, or other battery integrated system composed of single batteries. The actual application form of the energy storage device 5 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 5. This application embodiment only uses a multi-cell battery as an example for illustration.

[0043] In some embodiments, see Figure 1b , Figure 1b This is a schematic diagram of the structure of the second type of energy storage system 1 according to an embodiment of this application, and this application Figure 1b The embodiments are illustrated using industrial and commercial energy storage scenarios as an example. The energy storage device 5 of this application is not limited to energy storage scenarios on the power generation / distribution side.

[0044] This application provides a second type of energy storage system 1, which includes: an energy storage device 5, a high-voltage cable 2, a factory equipped with a first power conversion device 3, a photovoltaic-energy storage-charging station 6, and a vehicle 7. In some embodiments of industrial and commercial scenarios, the first power conversion device 3 can be a photovoltaic panel, which converts solar energy into electrical energy and stores it in the energy storage device 5 in the factory. In the event of a power grid failure, the energy storage device 5 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 5 in conjunction with the high-voltage cable 2 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 first power conversion device 3 can also convert solar energy into electrical energy and store it in the energy storage device 5 of the photovoltaic-energy storage-charging station 6, directly charging the vehicle 7 through the photovoltaic-energy storage-charging station 6, which is fast and convenient.

[0045] Optionally, the first power conversion device 3 may include, but is not limited to, photovoltaic panels and wind power conversion devices. The first power conversion device 3 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy and mechanical energy into electrical energy.

[0046] Please see Figure 2 , Figure 2 This is a schematic diagram of the structure of the energy storage device 5 provided in this application.

[0047] For ease of description, the width direction of the energy storage device 5 is defined as the X-axis direction, the length direction of the energy storage device 5 is defined as the Y-axis direction, and the thickness direction of the energy storage device 5 is defined as the Z-axis direction. The X-axis direction, Y-axis direction, and Z-axis direction are all perpendicular to each other.

[0048] This application provides an energy storage device 5, which may include, but is not limited to, a single battery cell, a battery module, a battery pack, or a battery system. Optionally, when the energy storage device 5 is a single battery cell, it may be, but is not limited to, at least one of cylindrical, prismatic, prismatic, or other shaped batteries. The single battery cell may be a rechargeable battery, meaning a battery that can be reactivated by charging after discharge to continue its use. The single battery cell may 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, or lead-acid battery, etc., and this application does not specifically limit its application. It should be noted that the actual application form of the energy storage device 5 provided in this application may be, but is not limited to, the listed products, and may also be other application forms. This application does not strictly limit the application form of the energy storage device 5. This application uses a prismatic battery as an example for illustration.

[0049] The energy storage device 5 includes a housing 10, a battery cell assembly (not shown), and an end cap assembly 20. The housing 10 has a receiving cavity (not shown) and an opening (not shown). The receiving cavity is located inside the housing 10 and contains electrolyte. The opening is located on one side of the receiving cavity and communicates with it. For example, the housing 10 may be made of aluminum; for instance, the housing 10 may be an aluminum shell. The battery cell assembly is housed in the receiving cavity. The battery cell assembly can be immersed in the electrolyte. The end cap assembly 20 is mounted on the housing 10, closes the opening, and is electrically connected to the battery cell assembly.

[0050] Please see Figure 3 and Figure 4 , Figure 3 yes Figure 2 The diagram shows the structure of the end cap assembly 20 in the energy storage device 5 under the first embodiment. Figure 4 yes Figure 3 The diagram shows an exploded view of the end cap assembly 20. The width of the end cap assembly 20 is parallel to the X-axis, the length is parallel to the Y-axis, and the thickness is parallel to the Z-axis.

[0051] The end cap assembly 20 includes an end cap 21, an explosion-proof valve 22, a protective plate 23, a lower insulating member 24, multiple support members 25, multiple limiting members 26, and a pole assembly 27. The explosion-proof valve 22 and the protective plate 23 are both mounted on the end cap 21. Along the thickness direction of the end cap 21, the lower insulating member 24, the support members 25, and the limiting members 26 are all located on the same side of the end cap 21. Along the length direction of the end cap assembly 20 (Y-axis direction in the figure), at least two support members 25 are located on opposite sides of the explosion-proof valve 22 and are spaced apart from the explosion-proof valve 22. There are two support members 25, namely a first support member 25a and a second support member 25b, which are located on opposite sides of the explosion-proof valve 22 and are spaced apart from the explosion-proof valve 22. Each limiting member 26 is located on the side of the explosion-proof valve 22 facing one of the support members 25 and is used to restrict the movement of the support member 25 toward the explosion-proof valve 22. The assembly includes four limiting members 26: two first limiting members 26a and two second limiting members 26b. The two first limiting members 26a are located on the side of the explosion-proof valve 22 facing the first support member 25a, and are spaced apart along the width direction (X-axis direction in the diagram) of the end cap assembly 20, thus limiting the movement of the first support member 25a toward the explosion-proof valve 22. The two second limiting members 26b are located on the side of the explosion-proof valve 22 facing the second support member 25b, and are spaced apart along the width direction of the end cap assembly 20, thus limiting the movement of the second support member 25b toward the explosion-proof valve 22. The pole assembly 27 is located on the side of the support member 25 away from the explosion-proof valve 22, and is spaced apart from the support member 25. It passes through the end cap 21 and the lower insulating member 24, and is also electrically connected to the cell assembly. There are two electrode post assemblies 27, namely a first electrode post assembly 27a and a second electrode post assembly 27b. The first electrode post assembly 27a is located on the side of the first support member 25a opposite to the explosion-proof valve 22, and the second electrode post assembly 27b is located on the side of the second support member 25b opposite to the explosion-proof valve 22. For example, the first electrode post assembly 27a is used as a negative electrode post assembly and is electrically connected to the negative tab of the battery cell assembly, and the second electrode post assembly 27b is used as a negative electrode post assembly and is electrically connected to the negative tab of the battery cell assembly.

[0052] In some other embodiments, there may be one or more support members 25, or there may be two, three or more limiting members 26. This application does not impose specific limitations on this.

[0053] Please refer to the following: Figure 5 , Figure 5 yes Figure 4 The diagram shows the structure of the end cap 21 and the lower insulator 24 in the end cap assembly 20 from another angle.

[0054] The end cap 21 has a first surface 211 and a second surface 212. Along the thickness direction of the end cap assembly 20 (Z-axis direction in the figure), the first surface 211 and the second surface 212 are arranged opposite to each other. The end cap 21 is provided with an explosion-proof hole 213 and a first pole hole 214. Both the explosion-proof hole 213 and the first pole hole 214 penetrate the first surface 211 and the second surface 212. Along the length direction of the end cap assembly 20, the explosion-proof hole 213 is located in the middle of the end cap 21. There are two first pole holes 214, located on opposite sides of the explosion-proof hole 213 along the length direction of the end cap assembly 20, and both are spaced apart from the explosion-proof hole 213.

[0055] Both the explosion-proof valve 22 and the protective plate 23 cover the explosion-proof hole 213 and are spaced apart and opposite to each other along the thickness direction of the end cap assembly 20. The explosion-proof valve 22 covers the opening of the explosion-proof hole 213 on the second surface 212. The protective plate 23 covers the opening of the explosion-proof hole 213 on the first surface 211 to protect the explosion-proof valve 22.

[0056] The lower insulating member 24, the support member 25, and the limiting member 26 are all located on the side of the second surface 212 opposite to the first surface 211. The lower insulating member 24 has a third surface 241 and a fourth surface 242. The third surface 241 is the surface of the lower insulating member 24 facing the end cap 21 and is disposed opposite to the second surface 212. The fourth surface 242 is disposed opposite to the third surface 241. The lower insulating member 24 includes an explosion-proof barrier 243, which is located in the middle of the lower insulating member 24 along the length of the end cap assembly 20 and is disposed opposite to the explosion-proof valve 22.

[0057] The lower insulating member 24 has a protrusion 244. Along the length of the end cap assembly 20, the protrusion 244 is located on one side of the explosion-proof fence 243 and is spaced apart from the explosion-proof fence 243. The protrusion 244 is provided on the fourth surface 242 and protrudes from the fourth surface 242 in a direction away from the third surface 241 (positive Z-axis direction in the figure). The protrusion 244 has a protruding surface 2441, a third side surface 2442, and a fourth side surface 2443. The protruding surface 2441 is the surface of the protrusion 244 away from the fourth surface 242 and is used to abut against the battery cell assembly. Along the length of the end cap assembly 20, the third side surface 2442 is the surface of the protrusion 244 near the explosion-proof valve 22 and is connected between the fourth surface 242 and the protruding surface 2441. The fourth side surface 2443 is disposed opposite to the third side surface 2442 and is connected between the fourth surface 242 and the protruding surface 2441. There are two protrusions 244, namely the first protrusion 244a and the second protrusion 244b, which are located on opposite sides of the explosion-proof fence 243.

[0058] The lower insulating member 24 is provided with a second pole hole 245, a groove 246, and a first vent hole 247. Along the length of the end cap assembly 20, the second pole hole 245 is located on the side of the protrusion 244 facing away from the explosion-proof fence 243 and is spaced apart from the protrusion 244. The second pole hole 245 penetrates the third surface 241 and the fourth surface 242 and communicates with the first pole hole 214. There are two second pole holes 245, each second pole hole 245 is located on the side of a protrusion 244 facing away from the explosion-proof fence 243 and communicates with a first pole hole 214.

[0059] The groove 246 is correspondingly provided with the protrusion 244. The opening of the groove 246 is located on the third surface 241. The groove 246 is recessed from the third surface 241 toward the protruding surface 2441 (positive Z-axis direction in the figure). The groove 246 has a first groove sidewall 2461 and a second groove sidewall 2462. Along the length of the end cap assembly 20, the first groove sidewall 2461 is close to the explosion-proof valve 22 and is disposed opposite to the third sidewall 2442. Along the length of the end cap assembly 20, the second groove sidewall 2462 is spaced apart from and opposite to the first groove sidewall 2461, and is disposed opposite to the fourth sidewall 2443. There are two grooves 246, each groove 246 is located between the explosion-proof fence 243 and a second pole hole 245, and is spaced apart from both the explosion-proof fence 243 and the second pole hole 245. The two grooves 246 are respectively the first groove 246a and the second groove 246b. The first groove 246a is correspondingly arranged with the first protrusion 244a, and the second groove 246b is correspondingly arranged with the second protrusion 244b. The first vent 247 penetrates the first groove sidewall 2461 and the third sidewall 2442, and communicates with the groove 246. There are multiple first vents 247, which are spaced apart along the width direction of the end cap assembly 20.

[0060] In this embodiment, the lower insulating member 24 includes a first sub-insulating member 24a and a second sub-insulating member 24b. The first sub-insulating member 24a has a first protrusion 244a, a second pole hole 245, a groove 246, and a plurality of first vent holes 247. Along the length direction of the end cap assembly 20, the second sub-insulating member 24b is located on one side of the first sub-insulating member 24a and includes an explosion-proof fence 243. The second sub-insulating member 24b has a second protrusion 244b, a second pole hole 245, a groove 246, and a plurality of first vent holes 247. The length L1 of the first sub-insulating member 24a is less than the length L2 of the second sub-insulating member 24b along the length direction of the end cap assembly 20.

[0061] Please refer to the following: Figure 6 and Figure 7 , Figure 6 yes Figure 4The diagram shows the structure of the support member 25 and the limiting member 26 in the end cap assembly 20. Figure 7 yes Figure 3 A partial structural schematic diagram of the end cap assembly 20 is shown. Wherein, Figure 7 The lower insulating element 24 is not shown.

[0062] The support member 25 and at least part of the limiting member 26 are both received in the groove 246. Specifically, the first support member 25a and two first limiting members 26a are both received in the first groove 246a, and the second support member 25b and two second limiting members 26b are both received in the second groove 246b. It should be noted that the first support member 25a and the second support member 25b have the same structure, and the first limiting members 26a and the second limiting members 26b have the same structure. The structures of the support member 25 and the limiting member 26 can be referred to in the relevant description below.

[0063] In this embodiment, the material of the support member 25 includes a conductive material. The support member 25 is housed in the groove 246 and can be wrapped by the lower insulating member 24, which can effectively prevent the support member 25 from contacting the battery cell assembly and prevent the support member 25 from being electrically connected to the battery cell assembly, thus avoiding short circuit between the positive and negative tabs of the battery cell assembly.

[0064] Each support member 25 has a first side surface 251, a second side surface 252, and a support surface 253. Along the length of the end cap assembly 20, the first side surface 251 is the surface of the support member 25 near the explosion-proof valve 22. The second side surface 252 is disposed opposite to the first side surface 251. The support surface 253 is the surface of the support member 25 away from the end cap 21 and connects between the first side surface 251 and the second side surface 252. When the energy storage device 5 experiences thermal runaway, and the lower insulating member 24 softens or even melts at high temperature and cannot contact the cell assembly, the support surface 253 of the support member 25 can contact the cell assembly to prevent the cell assembly from floating up and blocking the exhaust channel between the end cap 21 and the cell assembly, ensuring the smooth exhaust of the energy storage device 5 and improving the safety and reliability of the energy storage device 5.

[0065] Each support member 25 is provided with an exhaust channel 254, which passes through the first side 251 and the second side 252 and communicates with the first exhaust port 247. The thermal deformation temperature of the support member 25 is greater than that of the lower insulating member 24. When the energy storage device 5 experiences thermal runaway, and the lower insulating member 24 softens or even melts at high temperatures and cannot contact the battery cell assembly, the support surface 253 of the support member 25 can contact the battery cell assembly. Gas inside the energy storage device 5 can be discharged through the exhaust channel 254 from the explosion-proof port 213, ensuring smooth exhaust of the energy storage device 5 and improving its safety and reliability.

[0066] The exhaust channels 254 are multiple, and are spaced apart along the width direction of the end cap assembly 20. The number of exhaust channels 254 is F. The width of the end cap 21 along the width direction of the end cap assembly 20 is W, where 6mm ≤ W / F ≤ 20mm. This not only avoids W / F being too small, causing the support member 25 to occupy too much cross-section and resulting in insufficient cross-section of the exhaust channels 254, but also avoids W / F being too large, causing the exhaust channels 254 to be too wide and have a large span, which could lead to deformation due to compression by the cell assembly, resulting in the exhaust channels 254 being reduced or even flattened and losing their exhaust function.

[0067] In addition, the support member 25 also has a first channel wall 255 and a second channel wall 256. Both the first channel wall 255 and the second channel wall 256 face the exhaust channel 254. The second channel wall 256 is located on the side of the first channel wall 255 away from the end cap 21, and is spaced apart from and opposite to the first channel wall 255.

[0068] Along the length of the end cap assembly 20, at least a portion of the limiting member 26 is disposed opposite to the exhaust passage 254. Each limiting member 26 includes a first limiting portion 261 and a second limiting portion 262. Along the length of the end cap assembly 20, the first limiting portion 261 is located on the side of a support member 25 facing the explosion-proof valve 22 and is fixedly mounted on the second surface 212. Exemplarily, the first limiting portion 261 can be mounted to the second surface 212 by welding. Along the length of the end cap assembly 20, the projection of the first limiting portion 261 on the plane containing the first side surface 251 overlaps with at least a portion of the first side surface 251 and at least a portion of the exhaust passage 254, thereby restricting the movement of the support member 25 toward the explosion-proof valve 22. When thermal runaway occurs in the energy storage device 5, the lower insulating component 24 softens or even melts at high temperature. The support component 25 will move towards the explosion-proof valve 22 under the action of airflow. The first limiting part 261 can limit the movement distance of the support component 25 towards the explosion-proof valve 22, ensuring that the support surface 253 of the support component 25 can always abut against the cell assembly, so as to prevent the cell assembly from floating up and blocking the exhaust channel between the end cover 21 and the cell assembly, ensuring the smooth exhaust of the energy storage device 5, and improving the safety and reliability of the energy storage device 5.

[0069] The second limiting part 262 is fixedly connected to the side of the first limiting part 261 facing the support member 25 and extends into the exhaust channel 254 to ensure the assembly stability of the support member 25 in the end cover assembly 20, and to prevent the support member 25 from shifting under the action of airflow when thermal runaway occurs in the energy storage device 5, so as to ensure that the support member 25 always stays in the original position and the support member 25 can always abut against the cell assembly to prevent the cell assembly from floating up and blocking the exhaust channel between the end cover 21 and the cell assembly, ensuring the smooth exhaust of the energy storage device 5 and improving the safety and reliability of the energy storage device 5. Along the length of the end cap assembly 20, the projection of the second limiting part 262 on the plane of the first side 251 overlaps with at least part of the first side 251, and together with the first limiting part 261, limits the support member 25, thereby increasing the limiting area of ​​the limiting member 26 on the support member 25, improving the limiting reliability of the limiting member 26 on the support member 25, ensuring that the support surface 253 of the support member 25 can always abut against the cell assembly, so as to prevent the cell assembly from floating up and blocking the exhaust channel between the end cap 21 and the cell assembly, ensuring the smooth exhaust of the energy storage device 5, and improving the safety and reliability of the energy storage device 5.

[0070] In this embodiment, the material of the limiting member 26 is the same as that of the end cap 21, or the material of the limiting member 26 is the same as the main material of the end cap 21, so as to ensure the welding reliability of the limiting member 26 and the end cap 21 and avoid the explosion point caused by the different welding melting points of the limiting member 26 and the end cap 21.

[0071] Please refer to the following: Figure 8 and Figure 9 , Figure 8 yes Figure 2 The diagram shows the structure of the end cap assembly 20 in the energy storage device 5 under the second embodiment. Figure 9 yes Figure 8 A schematic diagram of the structure of the lower insulating member 24 in the end cap assembly 20 shown.

[0072] The end cap assembly 20 shown in this embodiment differs from the end cap assembly 20 shown in the first embodiment in that the lower insulating member 24 does not have a protrusion 244, and the groove 246 penetrates the third surface 241 and the fourth surface 242. Each support member 25 passes through a groove 246. The support surface 253 is located on the side of the fourth surface 242 opposite to the third surface 241 and is used to abut against the cell assembly. With this arrangement, the thickness of the support member 25 can be increased, which is beneficial to increasing the cross-section of the exhaust channel 254 and accelerating the exhaust. In addition, the end cap assembly 20 also includes an insulating layer 28, which is disposed on the support surface 253 to isolate the cell assembly and the support member 25, prevent the support member 25 from contacting the cell assembly, and prevent the support member 25 from being electrically connected to the cell assembly, which could lead to a short circuit between the positive and negative tabs of the cell assembly.

[0073] Please refer to the following: Figures 10 to 12 , Figure 10 yes Figure 2 The diagram shows the structure of the end cap assembly 20 in the energy storage device 5 under the third embodiment. Figure 11 yes Figure 10 The diagram shows the structure of the lower insulating member 24 in the end cap assembly 20. Figure 12 yes Figure 10 A partial structural schematic diagram of the end cap assembly 20 is shown. Wherein, Figure 12 The lower insulating element 24 is not shown.

[0074] The end cap assembly 20 shown in this embodiment differs from the end cap assembly 20 shown in the first embodiment in that the lower insulating member 24 is further provided with a second vent 248 and a clearance hole 249. The second vent 248 penetrates the second groove sidewall 2462 and the fourth sidewall 2443, and communicates with the groove 246 and the vent channel 254. There are multiple second vent holes 248, which are spaced apart along the width direction of the end cap assembly 20. The clearance hole 249 is located between the explosion-proof fence 243 and the protrusion 244, and is spaced apart from both the explosion-proof fence 243 and the protrusion 244, and penetrates the third surface 241 and the fourth surface 242. There are four clearance holes 249, including two first clearance holes 249a and two second clearance holes 249b. The two first clearance holes 249a are located between the explosion-proof fence 243 and the first protrusion 244a, and are spaced apart along the width direction of the end cap assembly 20. The two second clearance holes 249b are located between the explosion-proof fence 243 and the second protrusion 244b, and are also spaced apart along the width direction of the end cap assembly 20. At this time, the first sub-insulator 24a is also provided with multiple second vent holes 248 and two first clearance holes 249a, and the second sub-insulator 24b is also provided with multiple second vent holes 248 and two second clearance holes 249b.

[0075] The limiting member 26 is located between the support member 25 and the explosion-proof hole 213, and is spaced apart from the support member 25, and passes through the clearance hole 249. Specifically, each first limiting member 26a passes through a first clearance hole 249a and is spaced apart from the first support member 25a, and each second limiting member 26b passes through a second clearance hole 249b and is spaced apart from the second support member 25b. Along the length direction of the end cap assembly 20, the projection of the second limiting portion 262 on the plane of the first side surface 251 overlaps with at least a portion of the exhaust channel 254. Each limiting member 26 has a fifth surface 263, which is the surface of the limiting member 26 facing away from the end cap 21. The fifth surface 263 is located on the side of the raised surface 2441 facing the fourth surface 242, which can effectively prevent the limiting member 26 from contacting the cell assembly and prevent the limiting member 26 from being electrically connected to the cell assembly, thus avoiding short circuit between the positive and negative tabs of the cell assembly.

[0076] Please refer to the following: Figures 13 to 15 , Figure 13 yes Figure 2 The diagram shows the structure of the end cap assembly 20 in the energy storage device 5 under the fourth embodiment. Figure 14 yes Figure 13 The diagram shows the structure of the lower insulating member 24 in the end cap assembly 20. Figure 15 yes Figure 13 A partial structural schematic diagram of the end cap assembly 20 is shown. Wherein, Figure 15 The lower insulating element 24 is not shown.

[0077] The end cap assembly 20 shown in this embodiment differs from the end cap assembly 20 shown in the third embodiment above in that, along the length of the end cap assembly 20, at least a portion of the limiting member 26 is misaligned with the exhaust channel 254. The limiting member 26 includes a first limiting portion 261 and is integrally formed with the end cap 21 to reduce manufacturing costs of the end cap assembly 20. Along the length of the end cap assembly 20, the projection of the first limiting portion 261 onto the plane containing the first side surface 251 is misaligned with at least a portion of the exhaust channel 254 to reduce the impact of the first limiting portion 261 on the exhaust of the exhaust channel 254.

[0078] Please refer to the following: Figure 4 , Figure 16 and Figure 17 , Figure 16 yes Figure 4 An exploded view of the pole post assembly 27 in the end cap assembly 20 is shown. Figure 17 yes Figure 3 The diagram shows a cross-sectional view of the end cap assembly 20 after it has been cut along point II. Here, "cut along point II" means cutting along the plane containing line II; similar descriptions in the following text can be understood in the same way.

[0079] Each terminal assembly 27 passes through a second terminal hole 245 and a first terminal hole 214. Each terminal assembly 27 includes an upper insulating member 271, a terminal 272, a clamping block 273, and a sealing member 274. The upper insulating member 271 is located on the side of the first surface 211 facing away from the second surface 212. The upper insulating member 271 has a third terminal hole 2711, which penetrates the upper insulating member 271 along the thickness direction of the end cap assembly 20 and communicates with the first terminal hole 214. The terminal 272 passes through the second terminal hole 245, the first terminal hole 214, and the third terminal hole 2711 and is electrically connected to the cell assembly. The clamping block 273 is installed on the upper insulating member 271, sleeved on the terminal 272, and fixedly connected to the terminal 272. The sealing member 274 is sleeved on the terminal 272 and clamped between the end cap 21 and the terminal 272.

[0080] When the energy storage device 5 shown in this application experiences thermal runaway, after the lower insulating member 24 softens or even melts at high temperature, the support member 25 will move towards the explosion-proof valve 22 under the action of airflow. The limiting member 26 can limit the movement distance of the support member 25 towards the explosion-proof valve 22, ensuring that the support member 25 can always abut against the cell assembly, so as to prevent the cell assembly from floating up and blocking the exhaust channel between the end cover 21 and the cell assembly, ensuring the smooth exhaust of the energy storage device 5, and improving the safety and reliability of the energy storage device 5.

[0081] This application also provides an electrical device, which includes the aforementioned energy storage device 5, and the energy storage device 5 supplies power to the electrical device. The electrical device can be a new energy vehicle, a power storage station, a server, or other equipment that requires electricity.

[0082] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Where there is no conflict, the embodiments and features in the embodiments of this application can be combined with each other. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An end cap assembly for use in an energy storage device, characterized in that, The end cap assembly includes an end cap, an explosion-proof valve, multiple support members, and multiple limiting members. The end cap has a first surface and a second surface, which are opposite to each other along the thickness direction of the end cap assembly. The end cap has an explosion-proof hole that penetrates both the first and second surfaces. The explosion-proof valve is installed on the end cap and covers the explosion-proof hole. Multiple support members and multiple limiting members are located on the side of the second surface away from the first surface. Along the length direction of the end cap assembly, at least two support members are located on opposite sides of the explosion-proof hole and are spaced apart from it. Each support member has a first side surface and a second side surface. Along the length direction of the end cap assembly, the first side surface is the surface of the support member closest to the explosion-proof valve, and the second side surface... The end cap assembly is disposed opposite to the first side surface. Each of the supporting members is provided with an exhaust channel that passes through the first side surface and the second side surface. Each of the limiting members includes a first limiting part and a second limiting part. Along the length direction of the end cap assembly, the first limiting part is located between a supporting member and an explosion-proof hole, and is spaced apart from the explosion-proof hole, and is fixedly installed on the second surface. Along the length direction of the end cap assembly, the projection of the first limiting part on the plane where the first side surface is located overlaps with at least a portion of the first side surface and at least a portion of the exhaust channel. The second limiting part is fixedly connected to the side of the first limiting part facing the supporting member. Along the length direction of the end cap assembly, the projection of the second limiting part on the plane where the first side surface is located overlaps with at least a portion of the exhaust channel.

2. The end cap assembly according to claim 1, characterized in that, The plurality of support members include a first support member and a second support member. Along the length direction of the end cap assembly, the first support member and the second support member are respectively located on opposite sides of the explosion-proof hole. The plurality of limiting members include a plurality of first limiting members and a plurality of second limiting members. Along the width direction of the end cap assembly, the plurality of first limiting members are spaced apart, and the first limiting portion of each first limiting member is located between the first support member and the explosion-proof hole. Along the width direction of the end cap assembly, the plurality of second limiting members are spaced apart, and the first limiting portion of each second limiting member is located between the second support member and the explosion-proof hole.

3. The end cap assembly according to claim 1, characterized in that, The second limiting part extends into the exhaust passage.

4. The end cap assembly according to claim 1 or 3, characterized in that, Along the length of the end cap assembly, the projection of the second limiting portion onto the plane containing the first side overlaps with at least a portion of the first side.

5. The end cap assembly according to claim 1 or 2, characterized in that, The projection of the first limiting part on the plane where the first side is located is misaligned with at least a portion of the exhaust passage.

6. The end cap assembly according to claim 1 or 2, characterized in that, The end cap assembly further includes a lower insulating member located on the side of the second surface opposite to the first surface, the lower insulating member having a third surface facing the end cap; The lower insulating member is provided with a groove, and the opening of the groove is located on the third surface; The support member is received in the groove.

7. The end cap assembly according to claim 6, characterized in that, The lower insulating member also has a fourth surface, which is disposed opposite to the third surface; The groove has a first groove sidewall surface near the explosion-proof valve; The lower insulating member has a protrusion, which is located on the fourth surface and corresponds to the groove. The protrusion has a third side surface near the explosion-proof valve, which is opposite to the side wall of the first groove. The lower insulating member is provided with a first vent hole, which penetrates the first groove sidewall and the third side and is connected to the vent channel.

8. The end cap assembly according to claim 7, characterized in that, The groove also has a second groove sidewall, which is disposed opposite to the first groove sidewall. The protrusion also has a fourth side surface, which is disposed opposite to the third side surface and opposite to the side wall surface of the second groove. The lower insulating component is also provided with a second vent hole, which penetrates the second groove sidewall and the fourth sidewall and is connected to the vent channel.

9. The end cap assembly according to claim 6, characterized in that, At least a portion of the limiting member is received within the groove.

10. The end cap assembly according to claim 6, characterized in that, The lower insulating member also has a fourth surface, which is disposed opposite to the third surface. The lower insulating member is provided with a clearance hole, which is spaced apart from the groove and penetrates the third surface and the fourth surface. The limiting member is spaced apart from the supporting member and passes through the clearance hole.

11. The end cap assembly according to claim 7, characterized in that, The protrusion has a protruding surface that is opposite to the fourth surface, and the limiting member has a fifth surface that is opposite to the fourth surface, the fifth surface being located on the side of the protruding surface facing the fourth surface.

12. The end cap assembly according to claim 1 or 2, characterized in that, The end cap assembly further includes a lower insulating member located on the side of the second surface away from the first surface. The lower insulating member has a third surface and a fourth surface. The third surface is the surface of the lower insulating member facing the end cap, and the fourth surface is disposed opposite to the third surface. The lower insulating member is provided with a groove, which penetrates the third surface and the fourth surface; The support member passes through the groove.

13. The end cap assembly according to claim 12, characterized in that, The support member also has a support surface facing away from the end cap; The end cap assembly further includes an insulating layer disposed on the support surface.

14. The end cap assembly according to claim 1 or 2, characterized in that, There are multiple exhaust channels, which are spaced apart along the width direction of the end cap assembly.

15. An energy storage device, characterized in that, The device includes a housing, a battery cell assembly, and an end cap assembly as described in any one of claims 1 to 14. The housing has a receiving cavity and an opening. The receiving cavity is located inside the housing, and the opening communicates with the receiving cavity. The battery cell assembly is received in the receiving cavity. The end cap assembly is mounted on the housing and closes the opening, and is electrically connected to the battery cell assembly.

16. An electrical appliance, characterized in that, Includes the energy storage device as described in claim 15, wherein the energy storage device supplies power to electrical equipment.

Images