End cap assemblies, energy storage devices and electrical equipment

Abstract

This application provides an end cap assembly, an energy storage device, and an electrical appliance. In the end cap assembly, the first pole post includes a flange portion, a connecting portion, and a riveting portion. The flange portion is located on the side of the end cap away from the first upper insulating member, and the connecting portion is located on the side of the flange portion facing the first upper insulating member, and is integrally connected to the flange portion and the riveting portion. The connecting portion passes through the first pole post hole of the end cap and the second pole post hole of the first upper insulating member. The riveting portion is located on the side of the connecting portion away from the flange portion. In the riveting portion, a first part is fixedly connected to the connecting portion, a second part is located on the side of the first part away from the connecting portion, and the diameter of the second part is larger than the diameter of the first part. A third part is fixedly connected between the first part and the third part, and the diameter of the third part is larger than the diameter of the first part and smaller than the diameter of the second part. A first pressure block is installed on the first upper insulating member and sleeved on the riveting portion, and is fixedly connected to the riveting portion.

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 storage battery, is a battery that can be recharged after discharge to reactivate its active materials and continue to be used. The recyclable nature of rechargeable batteries has made them a primary power source for electrical devices. As the demand for rechargeable batteries increases, so do the performance requirements, especially the reliability. In rechargeable batteries, clamps are often used to increase the welding area between the end cap assembly and connecting pieces such as aluminum plates. However, the assembly stability between the clamps and the ends is poor, affecting the reliability of the end cap assembly. Summary of the Invention

[0003] This application provides an end cap assembly, an energy storage device, and an electrical device to improve the assembly stability between the pressure block and the pole post, and to improve the reliability of the end cap assembly.

[0004] In a first aspect, this application provides an end cap assembly for use in an energy storage device, comprising an end cap, a first upper insulating member, a first pole post, and a first pressure block;

[0005] The end cap is provided with a first pole post hole, which penetrates the end cap along the thickness direction.

[0006] The first upper insulating member is located on one side of the end cap in the thickness direction. The first upper insulating member is provided with a second pole hole. The second pole hole penetrates the first upper insulating member along the thickness direction and communicates with the first pole hole.

[0007] The first pole post includes a flange portion, a connecting portion, and a riveting portion. The flange portion is located on the side of the end cover away from the first upper insulating member. The connecting portion is located on the side of the flange portion facing the first upper insulating member and is connected to the flange portion and the riveting portion as an integral structure. The connecting portion passes through the first pole post hole and the second pole post hole. The riveting portion is located on the side of the connecting portion away from the flange portion.

[0008] The riveting part includes a first part, a second part, and a third part. The first part is fixedly connected to the connecting part. The diameter of the first part is 1.5 times less than or equal to the diameter of the flange part. The second part is located on the side of the first part away from the connecting part. The diameter of the second part is greater than the diameter of the first part. The third part is fixedly connected between the first part and the second part. The diameter of the third part is greater than the diameter of the first part and less than the diameter of the second part.

[0009] The first pressure block is installed on the first upper insulating member, sleeved on the riveting part, and fixedly connected to the riveting part.

[0010] In the end cap assembly shown in this application, the first electrode post and the first pressure block are fixedly connected by riveting, which improves the assembly stability between the first electrode post and the first pressure block and ensures the reliability of the end cap assembly. Furthermore, the diameter of the flange is larger than the diameter of the riveted part, which better ensures the expansion of the riveted part during the riveting assembly of the negative electrode post and the first pressure block, thus ensuring the riveting strength. Moreover, the larger diameter of the flange improves the pressure resistance of the negative electrode post, preventing the flange from being significantly expanded and deformed during riveting, ensuring the dimensional stability of the connection, preventing the thickness of the connection from being reduced due to riveting, ensuring that the creepage distance and clearance of the negative electrode post are not compressed, and ensuring the safe use of the energy storage device. In addition, since the diameter of the flange is greater than or equal to 1.5 times the diameter of the first part, the flange diameter is large enough to increase the effective current-carrying area of ​​the end cap assembly, reduce the internal resistance of the energy storage device, improve the current-carrying effect of the end cap assembly, and thus improve the energy efficiency of the energy storage device.

[0011] The third part includes a first abutting part, a first chamfered part, and a second chamfered part on its peripheral surface. The first abutting part is an inclined surface. The angle between the first abutting part and the thickness direction of the first pole post is greater than 0 degrees and less than 90 degrees. The first chamfered part is connected between the first abutting part and the peripheral surface of the first part. The second chamfered part is connected between the first abutting part and the peripheral surface of the second part.

[0012] The inclined surface between the first pole post and the first pressure block can improve the current carrying capacity of the end cap assembly and improve the energy efficiency of the energy storage device.

[0013] The first pressure block is provided with a riveting hole, which penetrates the first pressure block along the thickness direction and is connected and engaged with the riveting part.

[0014] The riveting hole includes a first hole, a second hole, and a third hole. The first hole is connected to the first part, and the hole wall of the first hole is connected to the peripheral surface of the first part. The second hole is located on the side of the first hole away from the end cap and is spaced apart from the first hole. It is connected to the second part, and the hole wall of the second hole is connected to the peripheral surface of the second part. The diameter of the second hole is 1.5 times less than or equal to the diameter of the first hole. The third hole connects the first hole and the second hole and is connected to the third part. The hole wall of the third hole is connected to the peripheral surface of the second part. The diameter of the third hole is greater than the diameter of the first hole and less than the diameter of the second hole.

[0015] The diameter of the second hole is greater than or equal to 1.5 times that of the first hole. This ensures that during the riveting process between the negative electrode post and the first pressure block, the riveting part can effectively expand and cooperate with the riveting hole for fixation. This not only ensures the expansion amount and riveting strength of the riveting part, but also allows the first abutting part and the second abutting part to form an inclined surface fit, thereby improving the current carrying capacity of the end cap assembly and improving the energy efficiency of the energy storage device.

[0016] The first pressure block has a first mounting surface facing the end cap, and the riveting hole penetrates the first mounting surface;

[0017] The connecting part has a mating surface that is away from the flange part. The mating surface is connected to the first assembly surface, which can increase the effective flow area of ​​the end cover assembly, reduce the internal resistance of the energy storage device, improve the flow effect of the end cover assembly, and thus improve the energy efficiency of the energy storage device.

[0018] The end cap is further provided with a third pole hole and an injection hole. Both the third pole hole and the injection hole penetrate the end cap along the thickness direction. The injection hole is located between the first pole hole and the third pole hole and is spaced apart from both the first pole hole and the third pole hole. The distance between the injection hole and the first pole hole is greater than the distance between the injection hole and the third pole hole.

[0019] The end cap assembly further includes a second upper insulating member, a second pole post, and a second pressure block. The second upper insulating member and the first upper insulating member are located on the same side of the end cap. The second upper insulating member is provided with a fourth pole post hole, which penetrates the second upper insulating member along the thickness direction and communicates with the third pole post hole.

[0020] The second electrode post passes through the third electrode post hole and the fourth electrode post hole;

[0021] The second pressure block is installed on the second upper insulating member, sleeved on the second pole post, and fixedly connected to the second pole post;

[0022] The resistivity of the second upper insulating component is 1×10⁻⁶. 3 ohm / sq to 1×10 10 The ohm / sq range is used to make the second upper insulator have weak conductivity.

[0023] Because the second upper insulating component has weak conductivity, there is a weak conductive connection between the second pole and the end cap. When the injection hole sprays liquid, it will not cause a short circuit when it overlaps with the second pole. The design of the injection hole close to the second positive pole hole can avoid the possibility of a short circuit when the injection hole overlaps with the first pole when it sprays liquid.

[0024] 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.

[0025] The end cap is also provided with an explosion-proof hole and a groove. The first pole hole and the explosion-proof hole both penetrate the first surface and the second surface and are spaced apart from each other. The opening of the groove is located on the first surface. The groove surrounds the explosion-proof hole and communicates with the explosion-proof hole. The groove has a bottom wall and a side wall. The bottom wall is opposite to the opening of the groove. The side wall surrounds the bottom wall and is connected to the bottom wall.

[0026] The end cap is also provided with a protrusion, which is located on the bottom wall of the groove and surrounds the explosion-proof hole, and is spaced apart from the side wall of the groove. The protrusion has a protruding surface, which is the surface of the protrusion that faces away from the bottom wall of the groove.

[0027] The end cap assembly also includes an explosion-proof valve and a protective plate. The explosion-proof valve is installed on the end cap and covers the opening of the explosion-proof hole on the second surface. The protective plate is installed on the raised surface and covers the explosion-proof valve, and is spaced apart from the side wall of the groove.

[0028] The groove design not only prevents electrolytes and other flowing substances on the end cap from flowing to the protective plate and contaminating the protective plate and explosion-proof valve, but also releases the welding stress when the explosion-proof valve is welded to the end cap, ensuring the sealing between the explosion-proof valve and the end cap, and ensuring the reliability of the explosion-proof valve and the protective plate.

[0029] The protective sheet has a third surface, which is the surface of the protective sheet that is away from the protrusion. The third surface is flush with the first surface, or the third surface is located on the side of the first surface facing the second surface.

[0030] The protective plate does not protrude from the end cap, which not only prevents the protective plate from being damaged or falling off due to impacts during the manufacturing or transportation of the energy storage device, ensuring the effective protection of the explosion-proof valve and the stability of the valve's opening, but also avoids interference with the top patch when attaching it, thus ensuring the reliability of the protective plate.

[0031] The protrusion further has a first circumferential surface, which is the surface of the protrusion facing the side wall of the groove, and is arranged around the protrusion and connected between the bottom wall of the groove and the protrusion surface.

[0032] The protective sheet also has a second circumferential surface, which surrounds and is connected to the third surface. The second circumferential surface is located between the first circumferential surface and the groove sidewall, and is spaced apart from the first circumferential surface and the groove sidewall.

[0033] The protective sheet covering the groove can reduce the exposed area of ​​the end cap, prevent the end cap from overlapping and conducting with external components, and help improve the reliability of the energy storage device.

[0034] The end cap is also provided with a liquid injection hole, which is located on one side of the groove and is spaced apart from the groove, and penetrates the first surface and the second surface;

[0035] The protective sheet includes a protective layer and an adhesive layer. The protective layer is located on the side of the raised surface facing away from the bottom wall of the tank. The adhesive layer is bonded between the protective layer and the raised surface. The adhesive layer has a third circumferential surface and a fourth circumferential surface. The third circumferential surface is the surface of the adhesive layer facing the side wall of the tank. The fourth circumferential surface is opposite to the third circumferential surface. The adhesive layer has a through hole located on the side of the adhesive layer facing away from the injection hole and penetrating the third circumferential surface and the fourth circumferential surface.

[0036] The through hole not only provides positioning for attaching the protective plate, but also serves the same function as the venting groove. It can balance the air pressure between the explosion-proof hole and the groove, preventing gas blockage between the explosion-proof valve and the protective plate. This can prevent the explosion-proof valve and the protective plate from bulging or sinking due to the internal and external pressure difference caused by altitude. Moreover, since the through hole is set far away from the injection hole, it can prevent electrolyte from entering the explosion-proof hole through the through hole and contaminating the explosion-proof valve when liquid is sprayed from the injection hole, thus ensuring the reliability of the explosion-proof valve.

[0037] The protrusion also has a fifth circumferential surface, which is disposed opposite to the first circumferential surface and connected to the protrusion surface;

[0038] The end cap is also provided with an exhaust groove, which is located on the side of the protrusion away from the injection hole. The exhaust groove passes through the protrusion surface, the first circumferential surface and the fifth circumferential surface, and is correspondingly provided with the through hole.

[0039] The venting groove can balance the air pressure between the explosion-proof hole and the groove, preventing gas blockage between the explosion-proof valve and the protective plate. This avoids the explosion-proof valve and the protective plate from bulging or denting due to the internal and external pressure difference caused by altitude. Moreover, since the venting groove is set far away from the injection hole, it can prevent electrolyte from entering the explosion-proof hole from the venting groove and contaminating the explosion-proof valve when liquid is sprayed from the injection hole, thus ensuring the reliability of the explosion-proof valve.

[0040] Secondly, this application provides an energy storage device, including a housing, a battery cell assembly, and any of the end cap assemblies mentioned above. The housing has a receiving cavity and an opening. The receiving cavity is located inside the housing, and the opening is located on the top side of the receiving cavity and communicates with the receiving cavity. The battery cell assembly is received in the receiving cavity, and the end cap assembly is installed on the housing and closes the opening.

[0041] Thirdly, this application provides an electrical device, including the energy storage device described above, wherein the energy storage device supplies power to the electrical device. Attached Figure Description

[0042] 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.

[0043] Figure 1 This is a schematic diagram of the structure of an energy storage system according to an embodiment of this application.

[0044] Figure 2 This is a schematic diagram of the energy storage device provided in this application;

[0045] Figure 3 yes Figure 2 The diagram shows the structure of the end cap assembly in the energy storage device.

[0046] Figure 4 yes Figure 3 A schematic diagram of the cross-sectional structure of the end cap assembly after it has been cut open at point II.

[0047] Figure 5 yes Figure 2 The exploded view of the end cap assembly is shown.

[0048] Figure 6 yes Figure 5 The diagram shows the structure of the end cap in the end cap assembly.

[0049] Figure 7 yes Figure 6 The diagram shows a cross-sectional structure of the end cap after it has been cut open at point II-II.

[0050] Figure 8 yes Figure 5A schematic diagram of the assembly structure of the end cap, explosion-proof valve and protective plate in the end cap assembly shown;

[0051] Figure 9 yes Figure 8 A schematic diagram of the cross-sectional structure of the assembly structure shown after being cut along point III-III;

[0052] Figure 10 yes Figure 5 The diagram shows the structure of the protective plate in the end cap assembly at another angle;

[0053] Figure 11 yes Figure 5 A schematic diagram of the assembly structure of the end cap assembly, including the end cap, explosion-proof valve, protective plate, and the second insulating film portion of the insulating film;

[0054] Figure 12 yes Figure 11 A schematic diagram of the cross-sectional structure of the assembly structure shown after being cut along line IV-IV.

[0055] Figure 13 yes Figure 5 A schematic diagram of the assembly structure of the end cap assembly, including the end cap, explosion-proof valve, protective plate, top patch, and the second insulating film portion of the insulating film;

[0056] Figure 14 yes Figure 13 A schematic diagram of the cross-sectional structure of the assembly structure shown after it is cut along point VV.

[0057] Figure 15 yes Figure 4 An enlarged structural diagram of region A in the end cap assembly shown;

[0058] Figure 16 yes Figure 4 A magnified structural diagram of region B in the end cap assembly shown;

[0059] Figure 17 yes Figure 16 A schematic diagram of the cross-sectional structure of the negative electrode post in the end cap assembly shown.

[0060] Figure 18 yes Figure 16 A schematic cross-sectional view of the first pressure block in the end cap assembly shown.

[0061] Figure 19 yes Figure 3 A schematic cross-sectional view of the end cap assembly shown, where the first pole post and the first pressure block, and the second pole post and the second pressure block are not riveted together.

[0062] Figure 20 yes Figure 19 An enlarged structural diagram of region C in the end cap assembly shown;

[0063] Figure 21 yes Figure 19 A schematic diagram of the structure of the first pole post in the end cap assembly shown;

[0064] Figure 22 yes Figure 19 The diagram shows the structure of the first pressure block in the end cap assembly.

[0065] The names corresponding to the labels in the figure are:

[0066] Energy storage system 400, high-voltage cable 410, first power conversion device 420, second power conversion device 430, energy storage device 100, housing 110, end cap assembly 120, end cap 10, explosion-proof valve 20, protective plate 30, lower insulating component 40, upper insulating component 50, pole post 60, pressure block 70, sealing ring 80, top patch 90, first upper insulating component 51, second upper insulating component 52, first pole post 61, second pole post 62, first pressure block 71, second pressure block 72, first sealing ring 81 Second sealing ring 82, first surface 101, second surface 102, explosion-proof hole 103, groove 104, injection hole 105, first pole hole 106, third pole hole 107, bottom wall of groove 1041, side wall of groove 1042, protrusion 11, protruding surface 111, first circumferential surface 112, fifth circumferential surface 113, vent groove 108, third surface 301, second circumferential surface 302, protective layer 31, adhesive layer 32, fourth surface 311, sixth circumferential surface 312, third circumferential surface 321, fourth Peripheral surface 322, through hole 303, second insulating film portion 132, sub-insulating film portion 133, free end face 134, first clearance hole 901, second clearance hole 902, third clearance hole 903, explosion-proof fence 41, liquid inlet hole 401, fifth pole hole 402, sixth pole hole 403, second pole hole 501, fourth pole hole 502, flange portion 63, riveting portion 64, connecting portion 65, mating surface 651, first part 66, second part 67, third part 68, first abutting part 6 81, First chamfered portion 682, Second chamfered portion 683, First mounting surface 701, Second mounting surface 702, Riveting hole 703, First hole portion 704, Second hole portion 705, Third hole portion 706, Second abutting portion 7061, Third chamfered portion 7062, Fourth chamfered portion 7063, First riveting portion 641, Second riveting portion 642, Connecting surface 643, First riveting hole portion 707, Second riveting hole portion 708, First hole wall surface 7081 and Second hole wall surface 7082. Detailed Implementation

[0067] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] 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:

[0072] (1) Large-scale energy storage power stations applied to wind power and photovoltaic power stations can assist renewable energy power generation in meeting grid connection requirements and improve the utilization rate of renewable energy. As a high-quality active / reactive power regulation power source on the power supply side, energy storage power stations can achieve load matching of power in time and space, enhance the absorption capacity of renewable energy, reduce instantaneous power changes, reduce the impact on the power grid, improve the absorption of new energy power generation, and are of great significance in power grid system backup, alleviating peak load power supply pressure and peak regulation and frequency regulation.

[0073] (2) Energy storage containers applied on the grid side mainly function as peak shaving, frequency regulation and grid congestion relief. In terms of peak shaving, they can realize peak shaving and valley filling of electricity load, that is, charging the energy storage battery when the electricity load is low and releasing the stored electricity during the peak electricity load period, thereby achieving a balance between power production and consumption.

[0074] (3) Small energy storage cabinets applied to the electricity consumption side mainly function as self-consumption of electricity, peak-valley price arbitrage, capacity cost management, and improvement of power supply reliability. Depending on the application scenario, electricity consumption side energy storage can be divided into industrial and commercial energy storage cabinets, household energy storage devices, energy storage charging piles, etc., which are generally used in conjunction with distributed photovoltaics. Industrial and commercial users can use energy storage for peak-valley price arbitrage and capacity cost management. In the electricity market implementing peak-valley pricing, by charging the energy storage system when the electricity price is low and discharging the energy storage system when the electricity price is high, peak-valley price arbitrage can be achieved, reducing electricity costs. In addition, industrial enterprises subject to two-part tariffs can use energy storage systems to store energy during off-peak hours and discharge during peak loads, thereby reducing peak power and the maximum demand declared, achieving the goal of reducing capacity charges. Household photovoltaics with energy storage can improve the level of self-consumption of electricity. Due to high electricity prices and poor power supply stability, the demand for household photovoltaic installations is driven. Given that photovoltaic power generation occurs during the day, while user load is generally higher at night, configuring energy storage can better utilize photovoltaic power, improve self-consumption levels, and reduce electricity costs. Furthermore, energy storage is needed in areas such as communication base stations and data centers for backup power.

[0075] 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, and this application Figure 1 The embodiments are illustrated using a shared energy storage scenario on the generation / distribution side as an example. The energy storage device 100 of this application is not limited to its generation / distribution side energy storage scenario.

[0076] This application provides an energy storage system 400, which includes: a high-voltage cable 410, a first power conversion device 420, a second power conversion device 430, and an energy storage device 100 provided in this application. In some embodiments of the power generation scenario, the second power conversion device 430 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 100 through grid connection. The energy storage device 100 is connected to the high-voltage cable 410 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 410. 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 100 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 the energy storage device 100 together with the high-voltage cable 410 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.

[0077] In some embodiments on the distribution network side, the first power conversion device 420 can be a photovoltaic power conversion device. The energy storage device 100 is connected to the high-voltage cable 410 and installed downstream of the high-voltage cable 410 between the user load and the user load. The power output by the photovoltaic power conversion device is stored in the energy storage device 100, which can respond in a timely manner to act as a backup power source when the power grid / distribution network fails. Alternatively, it can provide power supply support to alleviate line congestion when the high-voltage cable 410 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.

[0078] 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 420 and the second power conversion device 430 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy, and mechanical energy into electrical energy.

[0079] Optionally, the energy storage device 100 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.

[0080] Optionally, the energy storage device 100 may include, but is not limited to, single-cell batteries, or battery modules, battery packs, battery clusters, power banks, energy storage cabinets / containers, and other battery integrated systems composed of single-cell batteries. The actual application form of the energy storage device 100 provided in this application embodiment may be, but is not limited to, the listed products, and may also be other application forms. This application embodiment does not strictly limit the application form of the energy storage device 100. This application embodiment only uses a multi-cell battery as an example for illustration.

[0081] Please see Figure 2 , Figure 2 This is a schematic diagram of the energy storage device 100 provided in this application.

[0082] This application provides an energy storage device 100, 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 100 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, which is 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 100 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 100. This application uses a prismatic battery as an example for illustration.

[0083] The energy storage device 100 includes a housing 110, a battery cell assembly (not shown), an end cap assembly 120, and an insulating film (not shown). The housing 110 has a receiving cavity (not shown) and an opening (not shown). The receiving cavity is located inside the housing 110 and contains electrolyte. The opening is located on the top side of the receiving cavity and communicates with it. The housing 110 may be made of aluminum; for example, the housing 110 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 120 is mounted on the housing 110, closes the opening, and is electrically connected to the battery cell assembly. The length direction of the end cap assembly 120 is parallel to the length direction of the energy storage device 100, the width direction of the end cap assembly 120 is parallel to the width direction of the energy storage device 100, and the thickness direction of the end cap assembly 120 is parallel to the height direction of the energy storage device 100. The insulating film includes a first insulating film portion and a second insulating film portion. The first insulating film portion is disposed on the outer surface of the housing 110 and covers the outer surface of the housing 110, which not only protects the housing 110, but also prevents the housing 110 from contacting and conducting with other components. The second insulating film portion is connected to the first insulating film portion and is disposed on the end cap assembly 120.

[0084] Please see Figures 3 to 5 , Figure 3 yes Figure 2 The diagram shows the structure of the end cap assembly 120 in the energy storage device 100. Figure 4 yes Figure 3 The diagram shows a cross-sectional view of the end cap assembly 120 after it has been cut along point II. Figure 5 yes Figure 2 The diagram shows an exploded view of the end cap assembly 120. The phrase "cut along II" refers to cutting along the plane containing line II; similar descriptions in the following text can be understood in the same way.

[0085] The end cap assembly 120 includes an end cap 10, an explosion-proof valve 20, a protective plate 30, a lower insulating member 40, an upper insulating member 50, a pole post 60, a pressure block 70, a sealing ring 80, and a top patch 90. The explosion-proof valve 20 and the protective plate 30 are both mounted on the end cap 10. The lower insulating member 40 is located on one side of the end cap 10 along its thickness direction. The upper insulating member 50 is located on the other side of the end cap 10 along its thickness direction. That is, the upper insulating member 50 is located on the side of the end cap 10 opposite to the lower insulating member 40. There are two upper insulating members 50, namely a first upper insulating member 51 and a second upper insulating member 52. The first upper insulating member 51 and the second upper insulating member 52 are arranged alternately along the length of the end cap assembly 120. The first upper insulating member 51 serves as the negative electrode upper insulating member, and the second upper insulating member 52 serves as the positive electrode upper insulating member.

[0086] Along the thickness direction of the end cap assembly 120, the pole post 60 passes through the end cap 10, the lower insulating member 40, and the upper insulating member 50. There are two pole posts 60, namely a first pole post 61 and a second pole post 62. The first pole post 61 serves as the negative pole post, passing through the end cap 10, the lower insulating member 40, and the first upper insulating member 51. The second pole post 62 serves as the positive pole post, passing through the end cap 10, the lower insulating member 40, and the second upper insulating member 52. A pressure block 70 is installed on the upper insulating member 50, sleeved on the pole post 60, and fixedly connected to the pole post 60. There are two pressure blocks 70, namely a first pressure block 71 and a second pressure block 72. The first pressure block 71 serves as the positive pole riveting pressure ring, installed on the first upper insulating member 51, sleeved on the first pole post 61, and fixedly connected to the first pole post 61. The second pressure block 72 is used as a negative electrode riveting pressure ring. The second pressure block 72 is installed on the second upper insulating member 52, sleeved on the second pole post 62, and fixedly connected to the second pole post 62.

[0087] A sealing ring 80 is fitted onto the pole post 60 and clamped between the end cap 10 and the pole post 60. There are two sealing rings 80: a first sealing ring 81 and a second sealing ring 82. The first sealing ring 81 serves as the negative electrode sealing ring, fitted onto the first pole post 61 and clamped between the end cap 10 and the first pole post 61. The second sealing ring 82 serves as the positive electrode sealing ring, fitted onto the second pole post 62 and clamped between the end cap 10 and the second pole post 62. A top patch 90 is located on the side of the end cap 10 opposite to the lower insulating member 40.

[0088] Please see Figure 6 and Figure 7 , Figure 6 yes Figure 5 The diagram shows the structure of the end cap 10 in the end cap assembly 120. Figure 7 yes Figure 6 The diagram shows a cross-sectional view of the end cap 10 after it is cut open at point II-II.

[0089] The end cap 10 has a first surface 101 and a second surface 102. Along the thickness direction of the end cap 10 (the Z-axis direction in the diagram), the first surface 101 and the second surface 102 are arranged opposite to each other. The end cap 10 is provided with an explosion-proof hole 103, a groove 104, a liquid injection hole 105, a first pole hole 106, and a third pole hole 107. The explosion-proof hole 103, the liquid injection hole 105, the first pole hole 106, and the third pole hole 107 all penetrate the end cap 10 along its thickness direction. That is, the explosion-proof hole 103, the liquid injection hole 105, the first pole hole 106, and the third pole hole 107 all penetrate the first surface 101 and the second surface 102. Specifically, the explosion-proof hole 103 and the groove 104 are both located in the middle of the end cap 10. The opening of the groove 104 is located on the first surface 101. The groove 104 is recessed from the first surface 101 toward the second surface 102, surrounds the explosion-proof hole 103, and communicates with the explosion-proof hole 103. The groove 104 has a bottom wall 1041 and a side wall 1042. The bottom wall 1041 is positioned opposite the opening of the groove 104. The side wall 1042 surrounds the bottom wall 1041 and connects the bottom wall 1041 and the first surface 101.

[0090] The design of the groove 104 not only prevents electrolytes and other flowing substances on the end cap 10 from flowing to the protective plate 30 and contaminating the protective plate 30 and the explosion-proof valve 20, but also releases the welding stress when the explosion-proof valve 20 and the protective plate 30 are welded to the end cap 10, ensuring the sealing between the explosion-proof valve 20 and the protective plate 30 and the end cap 10, and ensuring the reliability of the explosion-proof valve 20 and the protective plate 30 in use.

[0091] The injection port 105 is located on one side of the explosion-proof port 103 and the groove 104, and is spaced apart from the explosion-proof port 103 and the groove 104. The first pole hole 106 is located on the side of the explosion-proof port 103 and the groove 104 away from the injection port 105, and is spaced apart from the explosion-proof port 103 and the groove 104. The third pole hole 107 is located on the side of the injection port 105 away from the explosion-proof port 103 and the groove 104, and is spaced apart from the injection port 105. The distance between the injection port 105 and the first pole hole 106 is greater than the distance between the injection port 105 and the third pole hole 107. The design of the injection port 105 being close to the third pole hole 107 avoids the possibility of a short circuit caused by the injection port 105 overlapping with the first pole 61 when injecting liquid.

[0092] The end cap 10 also has a protrusion 11, which is located on the bottom wall surface 1041 of the groove and extends from the bottom wall surface 1041 toward the opening of the groove 104. It is spaced apart from the side wall surface 1042 of the groove and surrounds the explosion-proof hole 103. The protrusion 11 has a protruding surface 111, a first circumferential surface 112, and a fifth circumferential surface 113. The protruding surface 111 is the surface of the protrusion 11 that faces away from the bottom wall surface 1041 of the groove and is located on the side of the first surface 101 facing the second surface 102, and is spaced apart from the first surface 101 in the thickness direction of the end cap 10. That is, the protruding surface 111 is recessed relative to the first surface 101. The distance between the protruding surface 111 and the first surface 101 along the thickness direction of the end cap 10 is H. The first circumferential surface 112 is the surface of the protrusion 11 facing the side wall 1042 of the groove, and is arranged around the protrusion 111 and connected between the protrusion 111 and the bottom wall 1041 of the groove. The fifth circumferential surface 113 is arranged opposite to the first circumferential surface 112 and is flush with the wall of the explosion-proof hole 103.

[0093] In addition, the end cap 10 is also provided with an exhaust groove 108, which is located on the side of the protrusion 11 away from the injection hole 105. The opening of the exhaust groove 108 is located on the protrusion surface 111, and the exhaust groove 108 penetrates the first circumferential surface 112 and the fifth circumferential surface 113, and connects the explosion-proof hole 103 and the groove 104. The exhaust groove 108 can not only balance the air pressure between the explosion-proof hole 103 and the groove 104, avoiding gas blockage between the explosion-proof valve 20 and the protective plate 30, and preventing the explosion-proof valve 20 and the protective plate 30 from bulging or sinking due to the internal and external pressure difference caused by altitude, but also, because the exhaust groove 108 is set away from the injection hole 105, it can prevent the electrolyte from entering the explosion-proof hole 103 from the exhaust groove 108 and contaminating the explosion-proof valve 20 when liquid is sprayed from the injection hole 105, so as to ensure the reliability of the explosion-proof valve 20.

[0094] Please see Figures 8 to 10 , Figure 8 yes Figure 5 The diagram shows the assembly structure of the end cap 10, explosion-proof valve 20, and protective plate 30 in the end cap assembly 120. Figure 9 yes Figure 8 The diagram shows a cross-sectional view of the assembled structure after it has been cut along point III-III. Figure 10 yes Figure 5 The diagram shows the structure of the protective sheet 30 in the end cap assembly 120 from another angle.

[0095] The explosion-proof valve 20 covers the opening of the explosion-proof hole 103 on the second surface 102. When the energy storage device 100 experiences thermal runaway, the explosion-proof valve 20 will open, and the high-temperature gas inside the energy storage device 100 will be ejected from the explosion-proof hole 103 to prevent the energy storage device 100 from exploding and to ensure the reliability of the energy storage device 100.

[0096] The protective plate 30 is installed in the groove 104 and covers the explosion-proof hole 103 and the explosion-proof valve 20 to protect the explosion-proof valve 20. Specifically, the protective plate 30 is installed on the raised surface 111 and spaced apart from the groove sidewall 1042. The protective plate 30 has a third surface 301 and a second circumferential surface 302. The third surface 301 is the surface of the protective plate 30 that faces away from the raised surface 111. The third surface 301 is flush with the first surface 101, or located on the side of the first surface 101 facing the second surface 102. That is, the third surface 301 does not protrude relative to the first surface 101, which not only prevents the protective plate 30 from being damaged or falling off due to impact during the manufacturing or transportation of the energy storage device 100, ensuring that the protective plate 30 effectively protects the explosion-proof valve 20 and ensures the opening stability of the explosion-proof valve 20, but also avoids interference with the top patch 90 when it is subsequently attached, ensuring the reliability of the protective plate 30.

[0097] The second circumferential surface 302 is disposed around and connected to the third surface 301. Specifically, the second circumferential surface 302 is the surface of the protective plate 30 facing the groove sidewall 1042, and is spaced apart from and opposite to the groove sidewall 1042. The second circumferential surface 302 is flush with the first circumferential surface 112, or the second circumferential surface 302 is located between the first circumferential surface 112 and the groove sidewall 1042, and is spaced apart from both. In some other embodiments, the second circumferential surface 302 may also be located on the side of the first circumferential surface 112 away from the groove sidewall 1042, and is spaced apart from the first circumferential surface 112. In this case, the second circumferential surface 302 may be perpendicular to the protruding surface 111.

[0098] In this embodiment, the protective sheet 30 includes a protective layer 31 and an adhesive layer 32. The protective layer 31 is located on the side of the raised surface 111 facing away from the bottom wall surface 1041 of the groove, and is spaced apart from the raised surface 111. The protective layer 31 has a third surface 301, a fourth surface 311, and a sixth peripheral surface 312. The fourth surface 311 is disposed opposite to the third surface 301. The sixth peripheral surface 312 is the surface of the protective layer 31 facing the side wall surface 1042 of the groove, and is spaced apart from the side wall surface 1042, and connects between the third surface 301 and the fourth surface 311.

[0099] The adhesive layer 32 is located between the protective layer 31 and the raised surface 111, and is bonded between the protective layer 31 and the raised surface 111. Specifically, the adhesive layer 32 is located between the fourth surface 311 and the raised surface 111, and is bonded between the fourth surface 311 and the raised surface 111. The adhesive layer 32 has a third circumferential surface 321 and a fourth circumferential surface 322. The third circumferential surface 321 is the surface of the adhesive layer 32 facing the groove sidewall 1042, and is spaced apart from the groove sidewall 1042. The third circumferential surface 321 is flush with the sixth circumferential surface 312, and the second circumferential surface 302 includes the sixth circumferential surface 312 and the third circumferential surface 321. The fourth circumferential surface 322 is disposed opposite to the third circumferential surface 321.

[0100] The protective sheet 30 has a through hole 303, which is located on the side of the adhesive layer 32 away from the injection hole 105. The opening of the through hole 303 is located on the surface of the adhesive layer 32 opposite to the protective layer 31. The through hole 303 penetrates the third circumferential surface 321 and the fourth circumferential surface 322, and connects the explosion-proof hole 103 and the groove 104. The through hole 303 is correspondingly provided with the vent groove 108 and communicates with the vent groove 108.

[0101] The through hole 303 not only provides positioning for attaching the protective plate 30, but also serves the same function as the vent groove 108. It can balance the air pressure between the explosion-proof hole 103 and the groove 104, preventing the gas from sealing between the explosion-proof valve 20 and the protective plate 30. This prevents the explosion-proof valve 20 and the protective plate 30 from bulging or sinking due to the internal and external pressure difference caused by altitude. Moreover, since the through hole 303 is located far away from the injection hole 105, it can prevent electrolyte from entering the explosion-proof hole 103 through the through hole 303 and contaminating the explosion-proof valve 20 when the injection hole 105 sprays liquid, thus ensuring the reliability of the explosion-proof valve 20.

[0102] Please see Figure 11 and Figure 12 , Figure 11 yes Figure 5 The diagram shows the assembly structure of the end cap 10, explosion-proof valve 20, and protective plate 30 with the second insulating film portion 132 of the insulating film in the end cap assembly 120. Figure 12 yes Figure 11 The diagram shows a cross-sectional view of the assembled structure after it is cut along line IV-IV.

[0103] The second insulating film portion 132 is disposed on the first surface 101, covering a portion of the groove 104, and is spaced apart from the injection hole 105, the first electrode hole 106, and the third electrode hole 107. The second insulating film portion 132 includes two sub-insulating film portions 133. Along the width direction of the end cap 10, the two sub-insulating film portions 133 are respectively disposed on opposite sides of the protective sheet 30, spaced apart from the protective sheet 30, and covering opposite ends of the groove 104. Each sub-insulating film portion 133 includes a free end face 134 facing the protective sheet 30. The orthographic projection of the free end face 134 onto the plane containing the bottom wall surface 1041 of the groove is located between the first circumferential surface 112 of the protrusion 11 and the side wall surface 1042 of the groove, and is spaced apart from both the first circumferential surface 112 and the side wall surface 1042. The orthographic projection of the free end face 134 onto the plane of the bottom wall surface 1041 of the groove is located between the second circumferential surface 302 of the protective sheet 30 and the side wall surface 1042 of the groove, and is spaced apart from the second circumferential surface 302.

[0104] Please see Figure 5 , Figure 13 and Figure 14 , Figure 13 yes Figure 5 The diagram shows the assembly structure of the end cap 10, explosion-proof valve 20, protective plate 30, and top patch 90 with the second insulating film portion 132 of the insulating film in the end cap assembly 120. Figure 14 yes Figure 13 The diagram shows a cross-sectional view of the assembled structure after it has been cut along point VV.

[0105] A top patch 90 is disposed on the first surface 101, covering a portion of the groove 104, and covering the injection hole 105 and the second insulating film portion 132. The top patch 90 is provided with a first clearance hole 901, a second clearance hole 902, and a third clearance hole 903. The first clearance hole 901, the second clearance hole 902, and the third clearance hole 903 all penetrate the top patch 90 along its thickness direction. The first clearance hole 901 is located in the middle of the top patch 90 and avoids the protective sheet 30. The orthographic projection of the hole wall of the first clearance hole 901 onto the plane containing the bottom wall surface 1041 of the groove is located between the first peripheral surface 112 of the protrusion 11 and the side wall surface 1042 of the groove, and is spaced apart from both the first peripheral surface 112 and the side wall surface 1042. The orthographic projection of the wall surface of the first clearance hole 901 onto the plane of the bottom wall surface 1041 of the groove is located between the second peripheral surface 302 and the side wall surface 1042 of the protective plate 30, and is spaced apart from the second peripheral surface 302. The orthographic projection of the wall surface of the first clearance hole 901 onto the plane of the bottom wall surface 1041 of the groove is located between the orthographic projection of the free end face 134 onto the plane of the bottom wall surface 1041 of the groove and the side wall surface 1042, and is spaced apart from the orthographic projection of the free end face 134 onto the plane of the bottom wall surface 1041 of the groove.

[0106] Since the second insulating film portion 132 covers part of the groove, it improves the adhesion of the top patch 90 to the end cap 10 and reduces the suspended area of ​​the top patch 90. Furthermore, since the protective sheet 30, the second insulating film portion 132, and the top patch 90 all cover the groove 104, the exposed area of ​​the end cap 10 can be reduced, preventing the end cap 10 from overlapping and conducting with external components, which helps to improve the reliability of the energy storage device 100.

[0107] The second clearance hole 902 and the third clearance hole 903 are located on opposite sides of the first clearance hole 901, and are spaced apart from the first clearance hole 901. The second clearance hole 902 corresponds to the first pole hole 106 and is used to avoid the first upper insulating member 51 and the first pressure block 71. The third clearance hole 903 corresponds to the third pole hole 107 and is used to avoid the second upper insulating member 52 and the second pressure block 72.

[0108] Please refer to the following: Figure 15 , Figure 15 yes Figure 4 An enlarged structural diagram of region A in the end cap assembly 120 shown.

[0109] The lower insulating member 40 is located on the side of the second surface 102 opposite to the first surface 101. The lower insulating member 40 has an explosion-proof barrier 41, which is located in the middle of the lower insulating member 40 and is correspondingly arranged with the explosion-proof valve 20. When the energy storage device 100 experiences thermal runaway, the high-temperature gas inside the energy storage device 100 will reach the explosion-proof valve 20 through the explosion-proof barrier 41. After the explosion-proof valve 20 opens, the gas will be ejected through the explosion-proof hole 103 to ensure the reliability of the energy storage device 100.

[0110] The lower insulating member 40 is provided with an inlet hole 401, a fifth terminal hole 402, and a sixth terminal hole 403, all of which penetrate the lower insulating member 40 along its thickness direction. The inlet hole 401 is located on one side of the explosion-proof barrier 41, spaced apart from it, and corresponds to the injection hole 105. The fifth terminal hole 402 is located on the side of the explosion-proof barrier 41 opposite to the inlet hole 401, spaced apart from it, and corresponds to the first terminal hole 106. The sixth terminal hole 403 is located on the side of the inlet hole 401 opposite to it, spaced apart from it, and corresponds to the third terminal hole 107.

[0111] Please refer to the following: Figure 16 , Figure 16 yes Figure 4 An enlarged structural diagram of region B in the end cap assembly 120 shown.

[0112] The first upper insulating member 51 and the second upper insulating member 52 are both disposed on the side of the first surface 101 facing away from the second surface 102, and are spaced apart from each other. The first upper insulating member 51 has a second terminal hole 501, which penetrates the first upper insulating member 51 along its thickness direction and corresponds to and communicates with the first terminal hole 106. The second upper insulating member 52 has a fourth terminal hole 502, which penetrates the second upper insulating member 52 along its thickness direction and corresponds to and communicates with the third terminal hole 107. The resistivity of the second upper insulating member 52 is 1×10⁻⁶. 3 ohm / sq to 1×10 10 The distance between ohm and sq is used to make the second upper insulator 52 weakly conductive. It should be noted that because the second upper insulator 52 is weakly conductive, there is a weakly conductive connection between the second pole post 62 and the end cap 10. Therefore, when the liquid injection hole 105 sprays liquid and overlaps with the second pole post 62, a short circuit will not occur.

[0113] The first pole post 61 passes through the fifth pole post hole 402, the first pole post hole 106, and the second pole post hole 501. The second pole post 62 passes through the sixth pole post hole 403, the third pole post hole 107, and the fourth pole post hole 502. In this embodiment, the first pole post 61 and the second pole post 62 have the same structure. Next, taking the first pole post 61 as an example, the structure of the pole post 60 will be described in detail.

[0114] Please refer to the following: Figure 17 , Figure 17 yes Figure 16 A schematic cross-sectional view of the first pole post 61 in the end cap assembly 120 shown.

[0115] The first pole post 61 includes a flange portion 63, a riveting portion 64, and a connecting portion 65. The flange portion 63 is located on the side of the end cap 10 facing away from the first upper insulating member 51. The flange portion 63 is also located on the side of the lower insulating member 40 facing away from the second surface 102. Both the riveting portion 64 and the connecting portion 65 are located on the side of the flange portion 63 facing the first upper insulating member 51. The riveting portion 64 is spaced apart from the flange portion 63 and is fixedly connected to the first pressure block 71. The diameter of the riveting portion 64 is smaller than the diameter of the flange portion 63. The connecting portion 65 is fixedly connected between the flange portion 63 and the riveting portion 64, and is integrated with both the flange portion 63 and the riveting portion 64 into a single structure. The connecting portion 65 passes through the fifth pole post hole 402, the first pole post hole 106, and the second pole post hole 501. The diameter of the connecting portion 65 is smaller than the diameter of the flange portion 63 but larger than the diameter of the riveting portion 64. The connecting part 65 has a mating surface 651 that is opposite to the flange part 63. The mating surface 651 is disposed around the riveting part 64 and is connected to the circumferential surface of the riveting part 64.

[0116] In this embodiment, the riveting portion 64 includes a first portion 66, a second portion 67, and a third portion 68. The first portion 66 is fixedly connected to the connecting portion 65. The diameter of the flange portion 63 is greater than or equal to 1.5 times the diameter of the first portion 66. The second portion 67 is located on the side of the first portion 66 facing away from the connecting portion 65 and is spaced apart from the first portion 66. The diameter of the second portion 67 is greater than the diameter of the first portion 66. The third portion 68 connects the first portion 66 and the second portion 67. The diameter of the third portion 68 is greater than the diameter of the first portion 66 and smaller than the diameter of the second portion 67.

[0117] The peripheral surface of the third part 68 includes a first abutting portion 681, a first chamfered portion 682, and a second chamfered portion 683. The first abutting portion 681 is spaced apart from the peripheral surfaces of the first part 66 and the second part 67. The first abutting portion 681 is an inclined surface, and the angle between the first abutting portion 681 and the thickness direction of the first pole post 61 is greater than 0 degrees and less than 90 degrees. The first chamfered portion 682 connects the peripheral surfaces of the first abutting portion 681 and the first part 66. The second chamfered portion 683 connects the peripheral surfaces of the first abutting portion 681 and the second part 67. Both the first chamfered portion 682 and the second chamfered portion 683 are arc-shaped surfaces.

[0118] Please refer to the following: Figure 4 and Figure 5 The first pressing block 71 is fitted onto the riveting portion 64 of the first pole post 61 and is fixedly connected to the riveting portion 64 of the first pole post 61. The second pressing block 72 is fitted onto the riveting portion of the second pole post 62 and is fixedly connected to the riveting portion of the second pole post 62. The first pressing block 71 is fixedly connected to the riveting portion 64 of the first pole post 61 by riveting, and the second pressing block 72 is fixedly connected to the riveting portion of the second pole post 62 by riveting. The first pressing block 71 and the first pole post 61, as well as the second pressing block 72 and the second pole post 62, are all fixed by riveting. This not only simplifies the assembly process of the end cap assembly 120 but also ensures the assembly stability between the first pressing block 71 and the first pole post 61, and between the second pressing block 72 and the second pole post 62, thus ensuring the reliability of the end cap assembly 120.

[0119] It should be noted that in this embodiment, the cooperation relationship between the first pressing block 71 and the first pole post 61 is the same as the cooperation relationship between the second pressing block 72 and the second pole post 62. Next, taking the first pressing block 71 as an example, the cooperation relationship between the pressing block 70 and the pole post 60 will be described in detail.

[0120] Please refer to the following: Figure 18 , Figure 18 yes Figure 16 A cross-sectional view of the first pressing block 71 in the end cap assembly 120.

[0121] The first pressure block 71 has a first mounting surface 701 and a second mounting surface 702. The first mounting surface 701 is the surface of the first pressure block 71 facing the end cap 10. The second mounting surface 702 is disposed opposite to the first mounting surface 701. The first pressure block 71 is provided with a riveting hole 703, which penetrates the first pressure block 71 along its thickness direction. That is, the riveting hole 703 penetrates both the first mounting surface 701 and the second mounting surface 702. The structure of the riveting hole 703 is adapted to the structure of the riveting portion 64 of the first pole post 61.

[0122] The riveting hole 703 includes a first hole portion 704, a second hole portion 705, and a third hole portion 706. The first hole portion 704 is located on the side of the riveting hole 703 near the first mounting surface 701 and penetrates the first mounting surface 701. The second hole portion 705 is located on the side of the first hole portion 704 facing the second mounting surface 702 and is spaced apart from the first hole portion 704. The diameter of the second hole portion 705 is larger than the diameter of the first hole portion 704. For example, the diameter of the second hole portion 705 is greater than or equal to 1.5 times the diameter of the first hole portion 704. The third hole portion 706 is located between the first hole portion 704 and the second hole portion 705 and connects the first hole portion 704 and the second hole portion 705. The diameter of the third hole portion 706 is larger than the diameter of the first hole portion 704 and smaller than the diameter of the second hole portion 705.

[0123] The wall surface of the third hole 706 includes a second abutting portion 7061, a third chamfered portion 7062, and a fourth chamfered portion 7063. The second abutting portion 7061 is spaced apart from the wall surfaces of the first hole 704 and the second hole 705. The second abutting portion 7061 is an inclined surface, and the angle between the second abutting portion 7061 and the thickness direction of the first pressing block 71 is greater than 0 degrees and less than 90 degrees. The third chamfered portion 7062 connects the second abutting portion 7061 and the wall surface of the first hole 704. The fourth chamfered portion 7063 connects the second abutting portion 7061 and the wall surface of the second hole 705. Both the third chamfered portion 7062 and the fourth chamfered portion 7063 are arc-shaped surfaces.

[0124] Please refer to the following: Figure 16The riveting portion 64 of the first pole post 61 is riveted to the riveting hole 703 of the first pressure block 71. Specifically, the mating surface 651 of the connecting portion 65 is connected to the first mounting surface 701 of the first pressure block 71; the first part 66 is connected to the first hole 704, with its peripheral surface connected to the hole wall surface of the first hole 704; the second part 67 is connected to the second hole 705, with its peripheral surface connected to the hole wall surface of the second hole 705; and the third part 68 is connected to the third hole 706, with its peripheral surface connected to the hole wall surface of the third hole 706. The first abutting portion 681 is connected to the second abutting portion 7061, the first chamfered portion 682 is connected to the third chamfered portion 7062, and the second chamfered portion 683 is connected to the fourth chamfered portion 7063.

[0125] It should be noted that the diameter of the flange portion 63 of the first pole post 61 is larger than the diameter of the riveting portion 64 and the diameter of the connecting portion 65. This better ensures the expansion of the riveting portion 64 during the riveting assembly of the first pole post 61 and the first pressure block 71, thus guaranteeing the riveting strength between the first pole post 61 and the first pressure block 71. Moreover, the larger diameter of the flange portion 63 enhances the pressure resistance of the first pole post 61, preventing the flange portion 63 from being significantly expanded and deformed during riveting. This ensures the dimensional stability of the connecting portion 65, prevents the thickness of the connecting portion 65 from being reduced due to riveting, and ensures that the creepage distance and electrical clearance of the first pole post 61 are not compressed, thus guaranteeing the safe operation of the energy storage device 100. Furthermore, since the diameter of the flange portion 63 is greater than or equal to 1.5 times the diameter of the first portion 66, the mating surface 651 of the connecting portion 65 abuts against the first assembly surface 701 of the first pressure block 71, which ensures that the diameter of the flange portion 63 is large enough to increase the effective flow area of ​​the end cap assembly 120, reduce the internal resistance of the energy storage device 100, improve the flow effect of the end cap assembly 120, and thus improve the energy efficiency of the energy storage device 100.

[0126] Furthermore, the diameter of the second hole 705 is greater than or equal to 1.5 times the diameter of the first hole 704, which ensures that during the riveting process of the first pole post 61 and the first pressure block 71, the riveting part 64 can effectively expand and cooperate with the riveting hole 703 for fixation. This not only ensures the expansion amount and riveting strength of the riveting part 64, but also allows the first abutting part 681 and the second abutting part 7061 to form an inclined surface fit, thereby improving the flow capacity of the end cap assembly 120 and improving the energy efficiency of the energy storage device 100.

[0127] Please see Figures 19 to 21 , Figure 19 yes Figure 3The diagram shows a cross-sectional view of the end cap assembly 120 when the first pole post 61 and the first pressure block 71, and the second pole post 62 and the second pressure block 72 are not riveted together. Figure 20 yes Figure 19 An enlarged structural diagram of region C in the end cap assembly 120 shown. Figure 21 yes Figure 19 A schematic diagram of the structure of the first pole post 61 in the end cap assembly 120 shown.

[0128] Before the first pole post 61 is riveted to the first pressure block 71, the riveting portion 64 includes a first riveting portion 641 and a second riveting portion 642. The first riveting portion 641 is fixedly connected to the connecting portion 65. The diameter of the first riveting portion 641 is smaller than the diameter of the connecting portion 65, and the diameter of the flange portion 63 is greater than or equal to 1.5 times the diameter of the first riveting portion 641. The second riveting portion 642 is located on the side of the first riveting portion 641 opposite to the connecting portion 65 and is fixedly connected to the first riveting portion 641. For example, the diameter of the second riveting portion 642 is larger than the diameter of the first riveting portion 641 and smaller than the diameter of the connecting portion 65. The second riveting portion 642 has a connecting surface 643 facing the first riveting portion 641, and the connecting surface 643 connects between the circumferential surface of the first riveting portion 641 and the circumferential surface of the second riveting portion 642. For example, the included angle between the connecting surface 643 and the circumferential surface of the first riveting part 641 and the circumferential surface of the second riveting part 642 is 90 degrees.

[0129] Please refer to the following: Figure 22 , Figure 22 yes Figure 19 A schematic diagram of the structure of the first pressure block 71 in the end cap assembly 120 shown.

[0130] Before the first pressure block 71 is riveted to the first pole post 61, the riveting hole 703 includes a first riveting hole portion 707 and a second riveting hole portion 708. The first riveting hole portion 707 is located on the side of the riveting hole 703 closest to the first mounting surface 701 and penetrates the first mounting surface 701. The second riveting hole portion 708 is located on the side of the first riveting hole portion 707 facing the second mounting surface 702, communicates with the first riveting hole portion 707, and penetrates the second mounting surface 702. The diameter of the second riveting hole portion 708 is larger than the diameter of the first riveting hole portion 707, and the diameter of the second riveting hole portion 708 is greater than or equal to 1.5 times the diameter of the first riveting hole portion 707. The hole wall surface of the second riveting hole 708 includes a first hole wall surface 7081 and a second hole wall surface 7082. The first hole wall surface 7081 is connected to the second mounting surface 702, and the second hole wall surface 7082 is connected between the first hole wall surface 7081 and the hole wall surface of the first riveting hole 707. For example, the included angle between the second hole wall surface 7082 and the hole walls of the first hole wall surface 7081 and the first riveting hole 707 is 90 degrees.

[0131] Please see Figure 20 Before the first pole post 61 is riveted to the first pressure block 71, the riveting portion 64 of the first pole post 61 passes through the riveting hole 703 of the first pressure block 71, the first riveting portion 641 passes through the first riveting hole portion 707, and the second riveting portion 642 passes through the second riveting hole portion 708. The circumferential surface of the first riveting portion 641 abuts against the hole wall surface of the first riveting hole portion 707, the circumferential surface of the second riveting portion 642 abuts against the first hole wall surface 7081 of the second riveting hole portion 708, and the connecting surface 643 of the second riveting portion 642 abuts against the second hole wall surface 7082 of the second riveting hole portion 708.

[0132] Please refer to the following: Figure 16 When the first pole post 61 and the first pressure block 71 are riveted together, the riveting portion 64 deforms. Specifically, the portion of the first riveting portion 641 near the second riveting portion 642 and the portion of the second riveting portion 642 near the first riveting portion 641 deform to form the third portion 68 of the riveting portion 64. The portion of the first riveting portion 641 away from the second riveting portion 642 remains essentially unchanged to form the first portion 66 of the riveting portion 64. The portion of the second riveting portion 642 away from the first riveting portion 641 remains essentially unchanged to form the second portion 67 of the riveting portion 64.

[0133] Understandably, during the deformation of the riveting part 64, the hole wall surfaces of the first riveting hole 707 and the second riveting hole 708 will deform under the action of the riveting part 64. The portion of the hole wall surface of the first riveting hole 707 near the second riveting hole 708, the portion of the first hole wall surface 7081 near the first riveting hole 707, and the second hole wall surface 7082 will deform to form the hole wall surface of the third hole 706. The portion of the hole wall surface of the first riveting hole 707 away from the second riveting hole 708 will not deform much to form the hole wall surface of the first hole 704. The portion of the first hole wall surface 7081 away from the first riveting hole 707 will not deform much to form the hole wall surface of the second hole 705.

[0134] Since the diameter of the flange 63 is greater than or equal to 1.5 times the diameter of the first riveting part 641, and the diameter of the second riveting hole 708 is greater than or equal to 1.5 times the diameter of the first riveting hole 707, during the riveting process of the first pole post 61 and the first pressure block 71, the riveting part 64 can effectively expand and cooperate with the riveting hole 703 for fixation. This not only ensures the expansion amount and riveting strength of the riveting part 64, but also allows the first abutting part 681 and the second abutting part 7061 to form an inclined surface fit, thereby improving the flow capacity of the end cap assembly 120 and the energy efficiency of the energy storage device 100. It should be noted that after the first pole post 61 and the first pressure block 71 are riveted, the first pole post 61 and the first pressure block 71 can also be welded together to increase the assembly stability between the first pole post 61 and the first pressure block 71.

[0135] The first sealing ring 81 passes through the first pole post hole 106 and is fitted onto the connecting portion 65 of the first pole post 61, clamping between the flange portion 63 of the first pole post 61 and the end cap 10. This not only prevents direct contact and short circuit between the first pole post 61 and the end cap 10, but also seals the gap between the first pole post 61 and the end cap 10, ensuring the sealing reliability of the end cap assembly 120. The second sealing ring 82 passes through the third pole post hole 107 and is fitted onto the connecting portion of the second pole post 62, clamping between the flange portion of the second pole post 62 and the end cap 10. This not only prevents direct contact and short circuit between the second pole post 62 and the end cap 10, but also seals the gap between the second pole post 62 and the end cap 10, ensuring the sealing reliability of the end cap assembly 120.

[0136] In the end cap assembly 120 shown in this application, the protective sheet 30 does not protrude from the first surface 101 of the end cap 10. This not only prevents the protective sheet 30 from being damaged or falling off due to impacts during the manufacturing or transportation of the energy storage device 100, but also prevents interference with the top patch 90 during subsequent attachment, thus ensuring the reliability of the protective sheet 30. Furthermore, the protective sheet 30 and the top patch 90 cover the groove 104 to reduce the exposed area of ​​the end cap 10, preventing short circuits caused by contact between the end cap 10 and external components, and ensuring the reliability of the energy storage device 100.

[0137] This application also provides an electrical device, which includes the aforementioned energy storage device 100, and the energy storage device 100 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.

[0138] 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 by, Includes end cap, first upper insulator, first pole post and first pressure block; The end cap is provided with a first pole post hole, which penetrates the end cap along the thickness direction. The first upper insulating member is located on one side of the end cap in the thickness direction. The first upper insulating member is provided with a second pole hole. The second pole hole penetrates the first upper insulating member along the thickness direction and communicates with the first pole hole. The first pole post includes a flange portion, a connecting portion, and a riveting portion. The flange portion is located on the side of the end cover away from the first upper insulating member. The connecting portion is located on the side of the flange portion facing the first upper insulating member and is connected to the flange portion and the riveting portion as an integral structure. The connecting portion passes through the first pole post hole and the second pole post hole. The riveting portion is located on the side of the connecting portion away from the flange portion. The riveting part includes a first part, a second part, and a third part. The first part is fixedly connected to the connecting part. The diameter of the first part is 1.5 times less than or equal to the diameter of the flange part. The second part is located on the side of the first part away from the connecting part. The diameter of the second part is greater than the diameter of the first part. The third part is fixedly connected between the first part and the second part. The diameter of the third part is greater than the diameter of the first part and less than the diameter of the second part. The first pressure block is installed on the first upper insulating member, sleeved on the riveting part, and fixedly connected to the riveting part.

2. The end cap assembly of claim 1, wherein, The peripheral surface of the third part includes a first abutting part, a first chamfered part, and a second chamfered part. The first abutting part is an inclined surface. The angle between the first abutting part and the thickness direction of the first pole post is greater than 0 degrees and less than 90 degrees. The first chamfered part is connected between the first abutting part and the peripheral surface of the first part. The second chamfered part is connected between the first abutting part and the peripheral surface of the second part.

3. The end cap assembly of claim 1 or 2, wherein, The first pressure block is provided with a riveting hole, which penetrates the first pressure block along the thickness direction and is riveted to the riveting part; The riveting hole includes a first hole, a second hole, and a third hole. The first hole is riveted to the first part, and the hole wall of the first hole is connected to the peripheral surface of the first part. The second hole is located on the side of the first hole away from the end cap and is spaced apart from the first hole. It is connected to the second part, and the hole wall of the second hole is connected to the peripheral surface of the second part. The diameter of the second hole is 1.5 times less than or equal to the diameter of the first hole. The third hole connects the first hole and the second hole and is connected to the third part. The hole wall of the third hole is connected to the peripheral surface of the second part. The diameter of the third hole is greater than the diameter of the first hole and less than the diameter of the second hole.

4. The end cap assembly of claim 1 or 2, wherein, The first pressure block has a first mounting surface facing the end cover, and the connecting portion has a mating surface facing away from the flange portion, the mating surface being connected to the first mounting surface.

5. The end cap assembly of claim 1, wherein, The end cap is also provided with a third pole hole and an injection hole. The third pole hole and the injection hole both penetrate the end cap along the thickness direction of the end cap. The injection hole is located between the first pole hole and the third pole hole and is spaced apart from both the first pole hole and the third pole hole. The distance between the injection hole and the first pole hole is greater than the distance between the injection hole and the third pole hole. The end cap assembly further includes a second upper insulating member, a second pole post, and a second pressure block. The second upper insulating member and the first upper insulating member are located on the same side of the end cap. The second upper insulating member is provided with a fourth pole post hole, which penetrates the second upper insulating member along the thickness direction and communicates with the third pole post hole. The second electrode post passes through the third electrode post hole and the fourth electrode post hole; The second pressure block is installed on the second upper insulating member, sleeved on the second pole post, and fixedly connected to the second pole post; The resistivity of the second upper insulating member is between 1 x 10 3 ohm / sq and 1 x 10 10 ohm / sq.

6. The end cap assembly of claim 1, wherein, 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; The end cap is also provided with an explosion-proof hole and a groove. The first pole hole and the explosion-proof hole both penetrate the first surface and the second surface and are spaced apart from each other. The opening of the groove is located on the first surface. The groove surrounds the explosion-proof hole. The groove has a bottom wall and a side wall. The bottom wall is opposite to the opening of the groove. The side wall surrounds the bottom wall and is connected to the bottom wall. The end cap is also provided with a protrusion, which is located on the bottom wall of the groove and surrounds the explosion-proof hole, and is spaced apart from the side wall of the groove. The protrusion has a protruding surface, which is the surface of the protrusion that faces away from the bottom wall of the groove. The end cap assembly also includes an explosion-proof valve and a protective plate. The explosion-proof valve is installed on the end cap and covers the opening of the explosion-proof hole on the second surface. The protective plate is installed on the raised surface and covers the explosion-proof valve, and is spaced apart from the side wall of the groove.

7. The end cap assembly of claim 6, wherein, The protective sheet has a third surface, which is the surface of the protective sheet that is away from the protrusion, and the third surface is located on the side of the first surface facing the second surface.

8. The end cap assembly of claim 7, wherein, The protrusion also has a first circumferential surface, which is the surface of the protrusion facing the side wall of the groove, and is disposed around the protrusion and connected between the bottom wall of the groove and the protrusion surface; The protective sheet also has a second circumferential surface, which surrounds and is connected to the third surface. The second circumferential surface is located between the first circumferential surface and the groove sidewall, and is spaced apart from the first circumferential surface and the groove sidewall.

9. The end cap assembly of claim 8, wherein, The end cap is also provided with a liquid injection hole, which is located on one side of the groove and is spaced apart from the groove, and penetrates the first surface and the second surface; The protective sheet includes a protective layer and an adhesive layer. The protective layer is located on the side of the raised surface facing away from the bottom wall of the tank. The adhesive layer is bonded between the protective layer and the raised surface. The adhesive layer has a third circumferential surface and a fourth circumferential surface. The third circumferential surface is the surface of the adhesive layer facing the side wall of the tank. The fourth circumferential surface is opposite to the third circumferential surface. The adhesive layer has a through hole located on the side of the adhesive layer facing away from the injection hole and penetrating the third circumferential surface and the fourth circumferential surface.

10. The end cap assembly of claim 9, wherein, The protrusion also has a fifth circumferential surface, which is disposed opposite to the first circumferential surface and connected to the protrusion surface; The end cap is also provided with an exhaust groove, which is located on the side of the protrusion away from the injection hole. The exhaust groove passes through the protrusion surface, the first circumferential surface and the fifth circumferential surface, and is correspondingly provided with the through hole.

11. An energy storage device, characterized by, The device includes a housing, a battery cell assembly, and an end cap assembly as described in any one of claims 1 to 10. The housing has a receiving cavity and an opening. The receiving cavity is located inside the housing, and the opening is located on the top side of the receiving cavity and communicates with the receiving cavity. The battery cell assembly is received in the receiving cavity, and the end cap assembly is mounted on the housing and closes the opening.

12. An electrical device, characterized by It includes the energy storage device as described in claim 11, wherein the energy storage device supplies power to the electrical equipment.

Images