CN116742224A

CN116742224A - End cover assembly, energy storage device, energy storage module and electric equipment

Info

Publication number: CN116742224A
Application number: CN202311032223.1A
Authority: CN
Inventors: 徐卫东; 李茂松
Original assignee: Shenzhen Haichen Energy Storage Control Technology Co ltd; Xiamen Hithium Energy Storage Technology Co Ltd
Current assignee: Shenzhen Haichen Energy Storage Control Technology Co ltd; Xiamen Hithium Energy Storage Technology Co Ltd
Priority date: 2023-08-16
Filing date: 2023-08-16
Publication date: 2023-09-12

Abstract

The application relates to an end cover assembly, an energy storage device, an energy storage module and electric equipment, wherein the end cover assembly comprises: the top cover plate is provided with a body part and reinforcing parts, the body part is provided with a first surface and a second surface, the explosion-proof holes penetrate through the first surface and the second surface, and the two reinforcing parts are arranged on the second surface and are arranged on two sides of the explosion-proof holes along the width direction of the top cover plate; the lower plastic part is arranged on the second surface side of the top cover plate and is provided with a third surface and a fourth surface, and the groove is positioned on the third surface and is used for accommodating the reinforcing part; the explosion-proof valve plate seals the explosion-proof hole and is connected with the body part; the pole is provided with a first flange part and a column part which are connected, the first mounting hole penetrates through the first surface and the second surface, the second mounting hole penetrates through the third surface and the fourth surface, the sinking platform surrounds the periphery of the second mounting hole and is positioned on the fourth surface, the first flange part is arranged in the sinking platform, and the column part penetrates through the second mounting hole and the first mounting hole. The top cover sheet of the end cover assembly has higher structural strength.

Description

End cover assembly, energy storage device, energy storage module and electric equipment

Technical Field

The application relates to the technical field of energy storage, in particular to an end cover assembly, an energy storage device, an energy storage module and electric equipment.

Background

The secondary battery (Rechargeable battery) is also called a rechargeable battery or a storage battery, and is a battery that can be continuously used by activating an active material by charging after discharging the battery. The recyclable characteristic of the secondary battery gradually becomes a main power source of electric equipment, and as the demand of the secondary battery gradually increases, the performance requirements of people on all aspects of the secondary battery are higher and higher, and particularly the requirement on the high safety performance of the battery is higher. The accurate explosion opening and pressure release of the anti-explosion valve plate at a preset threshold often becomes a key factor for determining the safety performance of the battery.

In the technical field of the existing energy storage device, the anti-explosion valve plate is generally arranged on the top cover of the end cover assembly, and the anti-explosion valve plate is designed to be thinner than the top cover and used for opening and relieving pressure when the internal pressure of the energy storage device is overlarge, so that the energy storage device is prevented from explosion due to overlarge pressure, and the safety performance of the energy storage device is further improved. Therefore, the explosion opening of the anti-explosion valve plate at a preset threshold value is a key factor for improving the safety performance of the energy storage device; however, in order to increase the energy density of the energy storage device unit and reduce the cost, the volume of the energy storage device is made as large as possible, and the thickness of the top cover is made as small as possible, so that the structural strength of the area where the anti-explosion valve plate is located is reduced; when the energy storage device is used for a long time, the internal pressure of the energy storage device is gradually increased due to the fact that the electrode material continuously generates gas through side reaction, when the preset threshold value is not reached, the top cover with large area and low thickness is extruded and arched to deform, the structure of the area where the anti-explosion valve plate is located is further damaged, the explosion critical point of the anti-explosion valve plate is changed, and then the safety performance of the energy storage device is reduced.

Disclosure of Invention

In view of the above, the application provides an end cover assembly, an energy storage device, an energy storage module and electric equipment, wherein the top cover plate of the end cover assembly has higher structural strength.

In view of this, the present application provides an end cap assembly comprising: the top cover piece comprises a body part and reinforcing parts, wherein the body part is provided with a first surface and a second surface which are arranged in a back-to-back mode, the body part is also provided with explosion-proof holes, the explosion-proof holes penetrate through the first surface and the second surface respectively, the reinforcing parts are arranged on the second surface, the number of the reinforcing parts is two, the two reinforcing parts are arranged on two sides of the explosion-proof holes along the width direction of the top cover piece, and the reinforcing parts are convex rib parts protruding on the second surface; the lower plastic part is arranged on the second surface side of the top cover plate and is provided with a third surface and a fourth surface which are arranged in opposite directions, the third surface and the second surface are arranged in opposite directions, and the lower plastic part is provided with a groove positioned on the third surface and used for accommodating the reinforcing part; the explosion-proof valve plate seals the explosion-proof hole and is connected to the body part; the pole comprises a first flange part and a column part which are connected, the first flange part is far away from the first surface than the column part, the top cover piece is provided with a first mounting hole penetrating through the first surface and the second surface, the lower plastic part is provided with a second mounting hole penetrating through the third surface and the fourth surface, the lower plastic part is further provided with a sinking table surrounding the periphery of the second mounting hole and located on the fourth surface, the first flange part is arranged in the sinking table, and the column part sequentially penetrates through the second mounting hole and the first mounting hole.

Further, the reinforcing part extends along a first direction and comprises a first end and a second end which are oppositely arranged along the first direction; in a first direction: the range of the length d1 of the first end protruding out of the anti-explosion valve plate is as follows: the length d2 of the second end protruding out of the explosion-proof valve plate is in the range of 18 mm-86 mm, and d1 is smaller than or equal to: and d2 is more than or equal to 18mm and less than or equal to 86mm, wherein the first direction is the length direction of the top cover sheet.

Further, a distance d3 between the valve block and the reinforcing portion is in a range of: d3 is more than or equal to 4.5mm and less than or equal to 18.5mm.

Further, the ratio of the width d4 of the explosion-proof hole along the first direction to the length d5 of the reinforcing portion along the first direction is in the range of: d4/d5 is more than or equal to 0.05 and less than or equal to 0.25.

Further, the maximum diameter of the column portion is D1, and the diameter of the first mounting hole is D2, and then the relation is satisfied: D2-D1 is more than or equal to 0.9mm and less than or equal to 2.2mm.

Further, a difference between the width D4 of the groove along the second direction and the width D3 of the reinforcing portion along the second direction is in a range of: D4-D3 is more than or equal to 0.15mm and less than or equal to 1.25mm; wherein the second direction is a width direction of the top sheet, and the second direction intersects the first direction.

Further, the lower plastic part comprises a lower plastic body, the lower plastic body is provided with a third surface and a fourth surface which are arranged in a back-to-back mode, the third surface and the second surface are arranged in opposite directions, the range of the ratio of the height H1 of the reinforcing part to the maximum depth H2 of the groove is as follows in the direction in which the top cover plate and the lower plastic part are arranged in a stacked mode: H1/H2 is more than or equal to 0.4 and less than 1.

Further, in the direction in which the top cover sheet and the lower plastic member are stacked, the height H1 of the reinforcing portion ranges from: h1 is more than or equal to 1.05mm and less than or equal to 2.65mm.

Further, the lower plastic part further comprises two boss portions, the two boss portions are arranged on the fourth surface of the lower plastic body at intervals along the first direction, the groove is located between the two boss portions and is arranged with the two boss portions at intervals respectively, and the first direction is the length direction of the top cover plate.

Further, the orthographic projection of the lower plastic part on the second surface falls into the range of the second surface; along the first direction, the distance L1 between the front projection outer periphery of the second surface and the outer periphery of the second surface of the lower plastic part ranges from: l1 is more than or equal to 1.2mm and less than or equal to 2.4mm; along the second direction, the distance L2 between the front projection outer periphery of the second surface and the outer periphery of the second surface of the lower plastic part ranges from: l2 is more than or equal to 1.2mm and less than or equal to 2.4mm; the first direction is the length direction of the top cover sheet, the second direction is the width direction of the top cover sheet, and the first direction and the second direction intersect.

Further, the end cover assembly further comprises a sealing element, the sealing element is sleeved on the column body, the top cover sheet is provided with a first inner side wall which surrounds the first mounting hole, the lower plastic part is provided with a second inner side wall which surrounds the second mounting hole, and the sealing element is respectively abutted with the first inner side wall and the second inner side wall.

The application also provides an energy storage device comprising: the application provides an end cover assembly, an electrode assembly, a switching piece and a shell, wherein the switching piece is electrically connected with the electrode assembly and the end cover assembly, the shell is arranged on one side of the end cover assembly facing the switching piece, the shell is connected with the end cover assembly and is enclosed with the end cover assembly into a containing groove, and the containing groove is used for containing the electrode assembly and the switching piece.

The application also provides an energy storage module, which comprises: the application provides an energy storage device, a separation plate assembly and a plurality of electric connecting pieces, wherein the separation plate assembly is arranged on one side of the energy storage device and is used for preventing a plurality of energy storage devices from being connected in a short circuit manner; the electric connecting piece set up in the division board subassembly deviates from the one side of energy memory, a plurality of electric connecting piece are used for with a plurality of energy memory electricity is connected.

The application also provides electric equipment, which comprises: the energy storage device comprises an equipment body and the energy storage device provided by the application, wherein the energy storage device supplies power for the equipment body.

In the application, the reinforcing parts are arranged on two sides of the explosion-proof hole along the width direction of the top cover sheet, the reinforcing parts are convex rib parts protruding on the second surface, and the two reinforcing parts improve the structural strength of the top cover sheet, so that after the end cover assembly is assembled on an energy storage device and used for a period of time, the part of the top cover sheet, which is close to the explosion-proof hole, is not easy to collapse or arch, in other words, after the end cover sheet is used for a period of time, the top cover sheet can still be kept flat and closely attached to a lower plastic part, thereby improving the assembly yield of the end cover assembly. Further, when the end cover assembly is assembled in the energy storage module, and a plurality of energy storage devices are assembled in the energy storage module, the reinforcing part on the top cover plate improves the structural strength of the top cover sheet, so that when the pressure inside the energy storage devices reaches a certain value and the anti-explosion valve plate is exploded, the top cover sheet arches towards the direction close to the isolation plate assembly, thereby avoiding the isolation plate assembly and the electric connecting piece from jacking towards the direction away from the electrode assembly, and then avoiding affecting the electric connection stability of the adjacent energy storage devices and the electric connecting piece, and being beneficial to improving the safety performance of the energy storage devices and the energy storage module. In addition, in the assembly process of the end cover assembly, the first flange part of the pole penetrates through the second mounting hole and is arranged in the sinking platform, and the sinking platform positions and limits the position of the pole; further, the top cover plate and the lower plastic part are matched with each other through the reinforcing part and the groove, the reinforcing part can be clamped in the groove, the top cover plate is arranged on one side of the lower plastic part, the groove limits the further movement of the reinforcing part, so that the relative positions of the top cover plate and the lower plastic part are limited, and the top cover plate and the lower plastic part are prevented from sliding relatively to influence the further assembly of the end cover assembly. The cylinder portion of utmost point post passes first mounting hole, the recess has restricted the position of reinforcing part, thereby has restricted the top cap piece with the relative position of plastic part down, avoid when the top cap piece the inside wall of first mounting hole with cylinder portion contact and short circuit connection, still can avoid first inside wall of first mounting hole is right the cylinder portion is scraped and is rubbed, so as to prevent to scrape the metal chip that produces and drop to electrode assembly and with electrode assembly short circuit connection, improved the end cover assembly with energy memory's security performance has still reduced the assembly precision requirement, has improved the assembly efficiency of end cover assembly. Furthermore, when the reinforcing part is arranged in the groove, the reinforcing part is matched with the groove, namely, the reinforcing part is inserted in the groove, so that the structural strength of the lower plastic part is improved, the lower plastic part can not collapse after a period of use, and the product yield of the end cover assembly is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of an energy storage system according to an embodiment of the present application;

FIG. 2 is a circuit block diagram of an energy storage system according to an embodiment of the present application;

FIG. 3 is a schematic diagram illustrating an energy storage module according to an embodiment of the application;

FIG. 4 is an exploded view of an energy storage module according to an embodiment of the present application;

FIG. 5 is a schematic diagram of an energy storage device according to an embodiment of the application;

FIG. 6 is a schematic diagram illustrating an exploded structure of an energy storage device according to an embodiment of the present application;

FIG. 7 is a schematic view of an end cap assembly according to an embodiment of the present application;

FIG. 8 is a schematic view of an exploded view of an end cap assembly according to one embodiment of the present application;

FIG. 9 is a schematic view showing the structure of a top sheet according to an embodiment of the present application;

FIG. 10 is a schematic view of the structure of a top sheet according to yet another embodiment of the present application;

FIG. 11 is a schematic diagram of a lower plastic part according to an embodiment of the application;

FIG. 12 is a schematic view of a lower plastic part according to another embodiment of the present application;

FIG. 13 is a schematic view of a portion of an end cap assembly according to an embodiment of the present application;

FIG. 14 is a schematic view of a portion of an end cap assembly according to yet another embodiment of the present application;

FIG. 15 is a schematic view of a portion of an end cap assembly according to another embodiment of the present application;

FIG. 16 is a cross-sectional view of an end cap assembly taken along the line A-A in FIG. 14 in accordance with one embodiment of the present application;

FIG. 17 is a cross-sectional view of an end cap assembly taken along the direction B-B in FIG. 15 in accordance with one embodiment of the present application;

FIG. 18 is a schematic structural view of an end cap assembly according to yet another embodiment of the present application;

FIG. 19 is a cross-sectional view of an end cap assembly taken along the line C-C of FIG. 18 in accordance with one embodiment of the present application;

FIG. 20 is an enlarged view of an end cap assembly along dashed line E in FIG. 19 according to one embodiment of the present application;

FIG. 21 is a block diagram of a powered device according to an embodiment of the present application;

fig. 22 is a schematic structural diagram of an electric device according to an embodiment of the present application.

Reference numerals illustrate:

100-end cap assembly, 110-top cover sheet, 111-body portion, 1111-first surface, 1112-second surface, 1113-explosion vent, 1114-third edge, 1115-fourth edge, 1116-seventh edge, 1117-eighth edge, 112-reinforcement portion, 1121-first end, 1122-second end, 1123-recess, 1124-bead portion, 113-first mounting hole, 1131-first inner sidewall, 114-injection hole, 120-lower plastic piece, 121-groove, 1211-bead portion, 122-lower plastic body, 1221-third surface, 1222-fourth surface, 1223-first edge, 1224-second edge, 1225-fifth edge, 1226-sixth edge, 123-second mounting holes, 1231-second inner side walls, 124-sinking tables, 125-liquid feeding parts, 126-boss parts, 130-explosion-proof valve plates, 140-polar posts, 141-first flange parts, 142-column parts, 150-sealing parts, 151-second flange parts, 152-penetrating parts, 160-sealing glue nails, 170-upper plastic parts, 300-energy storage devices, 310-electrode assemblies, 320-switching parts, 330-shells, 331-accommodating grooves, 400-energy storage modules, 410-isolation plate assemblies, 420-electric connectors, 500-electric equipment, 510-equipment bodies, 600-energy storage systems, 610-user loads, 620-first electric energy conversion devices and 630-second electric energy conversion devices.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without any inventive effort, are intended to be within the scope of the application.

The terms first, second and the like in the description and in the claims and in the above-described figures are used for distinguishing between different objects and not necessarily for describing a sequential or chronological order. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those listed steps or elements but may include other steps or elements not listed or inherent to such process, method, article, or apparatus.

Reference herein to "an embodiment" or "implementation" means that a particular feature, structure, or characteristic described in connection with the embodiment or implementation may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.

The energy storage device such as a secondary battery is generally provided with a through hole on the top cover of the end cover assembly, and an explosion-proof valve plate or an explosion-proof sheet is arranged to seal the through hole, so that when the air pressure in the energy storage device is increased to a certain value, the explosion-proof valve plate or the explosion-proof sheet can be exploded in time for pressure relief. In the related art, in order to save the cost, the top cover is set thinner and thinner, so that after the energy storage device is used for a period of time, the position of the top cover provided with the explosion-proof hole is easy to arch upwards, namely, the bulge phenomenon occurs. When the secondary battery is assembled in the energy storage module, the energy storage module comprises a plurality of batteries, a separation plate assembly and an electric connection assembly, the batteries and the electric connection assembly are arranged on two opposite sides of the separation plate assembly, the separation plate assembly can prevent the electric connection assembly from being directly electrically connected with top covers of the batteries to cause short circuit, and the electric connection assembly comprises a plurality of electric connection pieces, and each electric connection piece is electrically connected with at least one battery so as to electrically connect the batteries. The top cap upwards arches or the explosion-proof valve block explodes when the top cap upwards buckles because structural strength is weaker after a period of use for division board subassembly and electric connection subassembly in the energy storage module also are jacked, have influenced the electric connection stability of other secondary batteries and electric connection spare.

Because of the strong timeliness and space properties of energy required by people, in order to reasonably utilize the energy and improve the utilization rate of the energy, one energy form needs to be stored by one medium or equipment and then converted into another energy form, and the energy is released in a specific energy form based on future application. At present, green energy sources such as photovoltaic, wind power and the like are developed. At present, the generation of green electric energy generally depends on photovoltaic, wind power, water potential and the like, but wind energy, solar energy and the like generally have the problems of strong intermittence and large fluctuation, which can cause unstable power grid, insufficient peak electricity consumption, too much electricity consumption and unstable voltage can cause damage to the electric power, so that the problem of 'wind abandoning and light abandoning' possibly occurs due to insufficient electricity consumption requirement or insufficient power grid acceptance, and the problem needs to be solved by relying on energy storage. The energy is converted into other forms of energy through physical or chemical means and is stored, the energy is converted into electric energy when needed and released, in short, the energy storage is similar to a large-scale 'charge pal', the electric energy is stored when the photovoltaic and wind energy are sufficient, and the stored electric power is released when needed.

Taking electrochemical energy storage as an example, the scheme provides an energy storage device, wherein a group of electrode assemblies are arranged in the energy storage device, chemical elements in the electrode assemblies are mainly used as energy storage media, and the charge and discharge process is accompanied with chemical reaction or change of the energy storage media.

The existing energy storage (i.e. energy storage) application scene is wider, including aspects such as (wind and light) power generation side energy storage, electric network side energy storage, base station side energy storage and user side energy storage, the types of corresponding energy storage devices include:

(1) The large energy storage container applied to the energy storage scene at the power grid side can be used as a high-quality active and reactive power regulation power supply in the power grid, so that the load matching of electric energy in time and space is realized, the renewable energy consumption capability is enhanced, and the large energy storage container has great significance in the aspects of standby of a power grid system, relieving peak load power supply pressure and peak regulation and frequency modulation;

(2) The small and medium energy storage electric cabinet is applied to industrial and commercial energy storage scenes (banks, markets and the like) at the user side, and the main operation mode is peak clipping and valley filling. Because of the large price difference of the electricity charge at the peak-valley position according to the electricity consumption requirement, after the energy storage equipment is arranged by a user, in order to reduce the cost, the energy storage cabinet/box is charged usually in the electricity price valley period; and in the peak period of electricity price, the electricity in the energy storage equipment is released for use, so that the purpose of saving electricity charge is achieved.

Referring to fig. 1 and 2, fig. 1 is a schematic structural diagram of an energy storage system 600 according to an embodiment of the application, and the embodiment of fig. 1 is illustrated by taking a user energy storage scenario as an example, and the energy storage device 300 of the application is not limited to the user energy storage scenario.

The present application also provides an energy storage system 600, the energy storage system 600 comprising: the first electric energy conversion device 620 and the second electric energy conversion device 630 are used for converting other forms of energy into electric energy, the first electric energy conversion device 620 and the second electric energy conversion device 630 are electrically connected with the user load 610, and the electric energy converted by the first electric energy conversion device 620 and the electric energy converted by the second electric energy conversion device 630 supply power for the user load 610; the energy storage device 300 is electrically connected to the user load 610, the first power conversion device 620 and the second power conversion device 630, respectively, the energy storage device 300 stores the power converted by the first power conversion device 620 and the second power conversion device 630, and the energy storage device 300 supplies power to the user load 610.

Optionally, the first power conversion device 620 and the second power conversion device 630 may convert at least one of solar energy, light energy, wind energy, heat energy, tidal energy, biomass energy, mechanical energy, etc. into electrical energy to provide a stable power source for the user load 610 and the energy storage device 300.

It will be appreciated that in the fig. 1 embodiment of the application, the consumer load 610 may be, but is not limited to being, a base station, a business side, etc., the first power conversion device 620 is a photovoltaic panel that can convert solar energy to electrical energy during periods of low electricity prices, and the energy storage device 300 is used to store the electrical energy and supply the electrical energy to the base station and business side for use during peak electricity prices, or to supply the electrical power during grid outage/outage. The second power conversion device 630 is a windmill that converts wind energy into power and supplies the power to at least one of the user load 610 and the energy storage device 300. The energy storage device 300 is used to store the electric energy and supply the electric energy to street lamps and household appliances for use at the time of peak electricity prices or supply the electric energy at the time of power failure/power outage of the electric network. The transmission of the electric energy can be performed by adopting a high-voltage cable.

The number of the energy storage devices 300 may be plural, and the energy storage devices 300 may be connected in series or parallel, and the energy storage devices 300 may be supported and electrically connected by using a separator (not shown). In the present embodiment, "a plurality of" means two or more. The energy storage device 300 may further be provided with an energy storage box outside for accommodating the energy storage device 300.

Alternatively, the energy storage device 300 may include, but is not limited to, a battery cell, a battery module, a battery pack, a battery system, and the like. The practical application form of the energy storage device 300 provided in the embodiment of the present application may be, but is not limited to, the listed products, and may be other application forms, and the embodiment of the present application does not strictly limit the application form of the energy storage device 300. The embodiment of the present application will be described by taking the energy storage device 300 as a multi-core battery. When the energy storage device 300 is a single battery, the energy storage device 300 may be at least one of a cylindrical battery, a prismatic battery, and the like.

Referring to fig. 3 and 4, the present application further provides an energy storage module 400, where the energy storage module 400 includes: the energy storage device 300, the isolation board assembly 410 and the plurality of electrical connectors 420 provided by the application, wherein the isolation board assembly 410 is arranged at one side of the energy storage device 300, and the isolation board assembly 410 is used for preventing a plurality of energy storage devices 300 from being connected in a short circuit manner; the electrical connectors 420 are disposed on a side of the partition board assembly 410 away from the energy storage device 300, and the electrical connectors 420 are used for electrically connecting the energy storage devices 300.

It can be appreciated that in the energy storage module 400, the plurality of electrical connectors 420 and the plurality of energy storage devices 300 are disposed on opposite sides of the separator assembly 410.

Optionally, a plurality of the energy storage devices 300 are electrically connected in at least one of series and parallel.

In this embodiment, the isolating plate assembly 410 is used to prevent a plurality of the energy storage devices 300 from being connected in a short circuit, and the plurality of the electrical connectors 420 are used to electrically connect a plurality of the energy storage devices 300 to increase the energy density of the energy storage module 400. In this embodiment, the end cap assembly 100 of the energy storage module 400 has a higher assembly yield, the structural strength of the top cover sheet 110 of the end cap assembly 100 is higher, so that collapse or arching still cannot occur after a period of use, in addition, when the air pressure in the energy storage device 300 reaches a certain value and the explosion-proof valve sheet 130 is exploded, the top cover sheet 110 cannot arch in a direction close to the separator assembly 410 under a larger impact force, so that arching of the separator assembly 410 and the electrical connector 420 in a direction away from the electrode assembly 310 is avoided, the stability of electrical connection between a plurality of the electrical connectors 420 and a plurality of the energy storage devices 300 is improved, and the safety performance of the energy storage module 400 is improved.

Referring to fig. 5 and 6, the present application further provides an energy storage device 300, where the energy storage device 300 includes: according to the end cover assembly 100, the electrode assembly 310, the adapter 320 and the shell 330 provided by the application, the adapter 320 is electrically connected with the electrode assembly 310 and the end cover assembly 100, the shell 330 is arranged on one side of the end cover assembly 100 facing the adapter 320, the shell 330 is connected with the end cover assembly 100 and surrounds the end cover assembly 100 into the accommodating groove 331, and the accommodating groove 331 is used for accommodating the electrode assembly 310 and the adapter 320.

It can be appreciated that in the energy storage device 300 according to the embodiment of the present application, the end cap assembly 100, the adaptor 320 and the electrode assembly 310 are sequentially disposed.

Alternatively, the energy storage device 300 provided by the present application may be, but is not limited to, a lithium ion secondary battery, a lithium ion primary battery, a lithium sulfur battery, a sodium lithium ion battery, a sodium ion battery, a magnesium ion battery, or the like.

In the embodiment of the present application, the top cover plate 110 of the end cover assembly 100 has a relatively high structural strength and the end cover assembly 100 has a relatively high assembly yield, so that when the end cover assembly 100 is assembled to the energy storage device 300, the end cover assembly 100 and the housing 330 are easily assembled, and the energy storage device 300 has a relatively high product yield and assembly yield. In the energy storage device 300, opposite ends of the adaptor 320 are electrically connected to the end cap assembly 100 and the electrode assembly 310, respectively, so as to charge or discharge the energy storage device 300. The housing 330 and the end cap assembly 100 are enclosed into a receiving groove 331 for receiving the electrode assembly 310 and the adapter 320, and the housing 330 may perform anti-collision protection and anti-dust protection on the electrode assembly 310 and the adapter 320.

Optionally, in some embodiments, the energy storage device 300 further includes an electrolyte (not shown) disposed in the accommodating groove 331 and at least partially infiltrating the electrode assembly 310. In this embodiment, the electrolyte is used to infiltrate the electrode assembly 310, and the electrolyte cooperates with the electrode assembly 310 to achieve charging or discharging of the energy storage device 300.

Referring to fig. 7 and 8-12, the present application provides an end cap assembly 100, the end cap assembly 100 comprising: the top cover sheet 110, the lower plastic member 120 and the anti-explosion valve sheet 130, wherein the top cover sheet 110 comprises a body portion 111 and reinforcing portions 112, the body portion 111 is provided with a first surface 1111 and a second surface 1112 which are arranged in opposite directions, the body portion 111 is further provided with anti-explosion holes 1113, the anti-explosion holes 1113 respectively penetrate through the first surface 1111 and the second surface 1112, the reinforcing portions 112 are arranged on the second surface 1112, the number of the reinforcing portions 112 is two, the two reinforcing portions 112 are arranged on two sides of the anti-explosion holes 1113 along the width direction of the top cover sheet 110, and the reinforcing portions 112 are convex rib portions 1124 protruding on the second surface 1112; the lower plastic part 120 is disposed on the second surface 1112 side of the top cover 110, the lower plastic part 120 has a third surface 1221 and a fourth surface 1222 disposed opposite to each other, the third surface 1221 is disposed opposite to the second surface 1112, the lower plastic part 120 has a groove 121 located on the third surface 1221, and the groove 121 is used for accommodating the reinforcing part 112; the explosion proof valve sheet 130 closes the explosion proof hole 1113 and is connected to the body 111; the pole 140 includes a first flange portion 141 and a column portion 142, the first flange portion 141 is disposed farther from the first surface 1111 than the column portion 142, the top cover 110 has a first mounting hole 113 penetrating the first surface 1111 and the second surface 1112, the lower plastic member 120 has a second mounting hole 123 penetrating the third surface 1221 and the fourth surface 1222, the lower plastic member 120 further has a sinking platform 124 surrounding the periphery of the second mounting hole 123 and located on the fourth surface 1222, the first flange portion 141 is disposed in the sinking platform 124, and the column portion 142 sequentially penetrates through the second mounting hole 123 and the first mounting hole 113.

It is to be appreciated that the lower plastic member 120 is disposed on the second surface 1112 side of the top cover 110, and the lower plastic member 120 may be disposed on a side of the reinforcing portion 112 facing away from the body portion 111.

It will be appreciated that the lower plastic part has a recess 121 in the third surface 1221, and that the recess 121 may be located on the surface of the lower plastic part 120 facing the top cover sheet 110.

As can be appreciated, the first surface 1111, the second surface 1112, the third surface 1221, and the fourth surface 1222 are sequentially disposed along the direction in which the top cover sheet 110 and the lower plastic member 120 are stacked.

Optionally, the end cap assembly 100 provided by the application is assembled on the energy storage device 300, and the end cap assembly 100 includes the anti-explosion valve plate 130, when the air pressure inside the energy storage device 300 reaches a preset value, the air will rush open the anti-explosion valve plate 130 to release the pressure, so as to avoid explosion of the energy storage device 300 caused by overlarge air pressure inside, and be beneficial to improving the safety performance of the energy storage device 300.

It will be appreciated that the grooves 121 are used to provide the reinforcing portions 112, and the grooves 121 are in one-to-one correspondence with the reinforcing portions 112, and one of the grooves 121 is used to provide the reinforcing portion 112, and the orthographic projection of the reinforcing portion 112 on the surface of the lower plastic member 120 facing the top cover sheet 110 falls within the range of the grooves 121.

It should be appreciated that the recess 121 is configured to receive the reinforcement portion 112, and the recess 121 may be configured to cooperate with the reinforcement portion 112 to limit the relative positions of the top cover 110 and the lower plastic member 120.

It is to be understood that the first mounting hole 113 and the second mounting hole 123 are communicated and sequentially disposed along the direction in which the top cover sheet 110 and the lower plastic member 120 are stacked.

It is to be understood that the column portion 142 and the first flange portion 141 are disposed in sequence along the direction in which the top cover sheet 110 and the lower plastic member 120 are stacked.

As can be appreciated, the reinforcing portion 112 is a rib portion 1124 protruding from the second surface 1112, and the rib portion 1124 can improve the structural strength of the top cover 110.

In this embodiment, the reinforcing portions 112 are disposed on two sides of the explosion-proof hole 1113 along the width direction of the top cover piece 110, the reinforcing portions 112 are protruding rib portions 1124 protruding on the second surface 1112, and the two reinforcing portions 112 improve the structural strength of the top cover piece 110, so that after the end cover assembly 100 is assembled to the energy storage device 300 and used for a period of time, the portion of the top cover piece 110 near the explosion-proof hole 1113 is not easy to collapse or arch, in other words, after a period of time, the top cover piece 110 can still be kept flat and closely attached to the lower plastic member 120, so as to improve the assembly yield of the end cover assembly 100. Further, when the end cap assembly 100 is assembled to the energy storage module 400, and the plurality of energy storage devices 300 are assembled to the energy storage module 400, the reinforcing portion 112 on the top cover sheet 110 improves the structural strength of the top cover sheet 110, so that when the pressure inside the energy storage devices 300 reaches a certain value and the explosion-proof valve sheet 130 is exploded, the top cover sheet 110 arches towards the direction close to the separator assembly 410, thereby preventing the separator assembly 410 and the electric connector 420 from being lifted towards the direction away from the electrode assembly 310, and further avoiding affecting the electric connection stability of the adjacent energy storage devices 300 and the electric connector 420, and being beneficial to improving the safety performance of the energy storage devices 300 and the energy storage module 400. In addition, during the assembly process of the end cap assembly 100, the first flange portion 141 of the pole 140 passes through the second mounting hole 123 and is disposed in the sinking platform 124, and the sinking platform 124 locates and limits the position of the pole 140; further, the top cover plate 110 and the lower plastic member 120 are matched with each other through the reinforcing portion 112 and the groove 121, the reinforcing portion 112 may be disposed in the groove 121 in a clamping manner, the top cover plate 110 is disposed on one side of the lower plastic member 120, and the groove 121 limits further movement of the reinforcing portion 112, so that the relative positions of the top cover plate 110 and the lower plastic member 120 are limited, and further assembly of the end cover assembly 100 due to relative sliding of the top cover plate 110 and the lower plastic member 120 is avoided. The column portion 142 of the pole 140 passes through the first mounting hole 113, and the groove 121 limits the position of the reinforcing portion 112, so as to limit the relative positions of the top cover sheet 110 and the lower plastic member 120, avoid contact and short-circuit connection between the inner side wall of the first mounting hole 113 and the column portion 142 when the top cover sheet 110 is mounted, and also avoid rubbing the column portion 142 by the first inner side wall 1131 of the first mounting hole 113, so as to prevent metal fragments generated by rubbing from falling to the electrode assembly 310 and short-circuit connection with the electrode assembly 310, improve the safety performance of the end cover assembly 100 and the energy storage device 300, reduce the assembly precision requirement, and improve the assembly efficiency of the end cover assembly 100. Furthermore, when the reinforcing portion 112 is disposed in the groove 121, the reinforcing portion 112 is matched with the groove 121, that is, the reinforcing portion 112 is inserted into the groove 121, so that the structural strength of the lower plastic member 120 is improved, the lower plastic member 120 still cannot collapse after a period of use, and the product yield of the end cap assembly 100 is improved.

Referring to fig. 7 to 10, alternatively, in some embodiments, the reinforcing portion 112 and the body portion 111 are integrally formed, and the reinforcing portion 112 is manufactured by using a planar metal plate and performing a stamping process, in this embodiment, the reinforcing portion 112 is protruding on the second surface 1112, the reinforcing portion 112 is a protruding rib portion 1124 protruding on the second surface 1112, and the protruding rib portion 1124 forms a concave region 1123 in a region corresponding to the orthographic projection of the first surface 1111. In the process of manufacturing the top cover plates 110, after the top cover plates 110 are formed by punching, the rib parts 1124 of one top cover plate 110 are disposed in the recessed areas 1123 of the other top cover plate 110, so that a plurality of top cover plates 110 can be stacked in sequence to form a neat column, which is beneficial to the transportation of a plurality of top cover plates 110, and can avoid damage caused by collision of a plurality of top cover plates 110, and is beneficial to reducing the transportation cost of the end cover assembly 100.

Optionally, in some embodiments, the top cover sheet 110 has a filling hole 114, and the filling hole 114 penetrates through the first surface 1111 and the second surface 1112 to fill the energy storage device 300 with electrolyte, and the end cover assembly 100 further includes a sealing nail 160, where the sealing nail 160 is used to seal the filling hole 114 when filling is completed. The sealant nails 160 can prevent the electrolyte from being polluted by moisture and oxygen in the air, so as to prevent the electrolyte from decreasing the infiltration effect of the electrolyte on the electrode assembly 310, and in addition, the sealant nails 160 can prevent metal scraps generated in the assembly process from falling into the energy storage device 300 to cause the short circuit of the energy storage device 300, thereby being beneficial to improving the safety performance of the energy storage device 300.

Referring to fig. 7 to 12, alternatively, in some embodiments, the groove 121 is formed by a stamping process, and in this embodiment, the groove 121 is recessed in the third surface 1221, and the groove 121 forms a protrusion 1211 in a region corresponding to the orthographic projection of the fourth surface 1222.

Optionally, in some embodiments, the lower plastic part 120 includes a lower plastic body 122 and a liquid-feeding portion 125, the lower plastic body 122 has a third surface 1221 and a fourth surface 1222 disposed opposite to each other, and the orthographic projection of the liquid-feeding portion 125 on the third surface 1221 at least partially overlaps the orthographic projection of the liquid-filling hole 114 on the third surface 1221.

In this embodiment, the liquid-feeding portion 125 is disposed opposite to the liquid-injecting hole 114, and when the end cap assembly 100 is assembled to the energy storage device 300 and electrolyte is injected into the liquid-injecting hole 114, the electrolyte will impact the liquid-feeding portion 125 and flow to the electrode assembly 310 along the liquid-feeding portion 125, so as to infiltrate the electrode assembly 310. The liquid-moving part 125 can prevent the electrolyte from directly impacting the electrode assembly 310 to drop the active materials in the electrode assembly 310, which is beneficial to improving the safety performance of the energy storage device 300. Furthermore, the liquid-feeding portion 125 can prevent the electrode assembly 310 from directly pressing the sealant nails 160 to crack the top cover sheet 110, which is beneficial to prolonging the service life of the end cover assembly 100.

Referring to fig. 7-13, in some embodiments, the reinforcement portion 112 extends along a first direction (as shown by X in fig. 13), and the reinforcement portion 112 includes a first end 1121 and a second end 1122 opposite to each other along the first direction; in a first direction: the length d1 of the first end 1121 protruding from the valve block 130 ranges from: the length d2 of the second end 1122 protruding from the valve plate 130 is 18mm or more and d1 or less than 86mm, and the range is as follows: and d2 is more than or equal to 18mm and less than or equal to 86mm, wherein the first direction is the length direction of the top cover sheet 110.

Specifically, in a first direction: the length d1 of the first end 1121 protruding from the explosion proof valve plate 130 may have, but is not limited to, values of 18mm, 20mm, 22mm, 23mm, 25mm, 28mm, 30mm, 36mm, 42mm, 48mm, 52mm, 55mm, 59mm, 62mm, 68mm, 70mm, 72mm, 75mm, 78mm, 80mm, 82mm, 86mm, etc.

Specifically, in a first direction: the length d2 of the second end 1122 protruding from the valve block 130 may have a value of, but is not limited to, 18mm, 20mm, 22mm, 23mm, 25mm, 28mm, 30mm, 36mm, 42mm, 48mm, 52mm, 55mm, 59mm, 62mm, 68mm, 70mm, 72mm, 75mm, 78mm, 80mm, 82mm, 86mm, etc.

It will be appreciated that the first end 1121 protrudes from the valve block 130, the second end 1122 protrudes from the valve block 130, and the length of the reinforcing portion 112 along the first direction may be greater than the length of the valve block 130 along the first direction, and both opposite ends of the reinforcing portion 112 protrude from the valve block 130.

In this embodiment, the reinforcement portion 112 extends along the first direction, so that the reinforcement portion 112 improves the structural strength of the top cover sheet 110 along the first direction, and after a period of use of the end cover assembly 100, the top cover sheet 110 can still be kept flat and is not easy to collapse due to gravity, so that the top cover sheet 110 can still be closely attached to the lower plastic member 120, and the assembly yield of the end cover assembly 100 is improved. In addition, the reinforcing portion 112 increases the deformation threshold of the top cover sheet 110, so as to avoid the phenomenon that the gas inside the energy storage device 300 lifts up the top cover sheet 110 to generate "bulge"; moreover, the structural strength of the top cover 110 is sufficient, and when the end cover assembly 100 is assembled in the energy storage device 300 and the air pressure inside the energy storage device 300 reaches a certain value, the air inside the energy storage device 300 will not arch the top cover 110 while bursting the anti-explosion valve plate 130, so as to avoid affecting the application of the energy storage device 300 in the energy storage module 400. When the length d1 of the first end 1121 protruding from the explosion-proof valve plate 130 satisfies 18mm less than or equal to d1 less than or equal to 86mm, and the length d2 of the second end 1122 protruding from the explosion-proof valve plate 130 satisfies 18mm less than or equal to d2 less than or equal to 86mm, the length d1 of the first end 1121 protruding from the explosion-proof valve plate 130 and the length d2 of the second end 1122 protruding from the explosion-proof valve plate 130 are both within reasonable ranges, so that the structural strength of the top cover sheet 110 along the first direction can be improved by the reinforcing portion 112, collapse or arch of the part of the top cover sheet 110 close to the explosion-proof hole 1113 after a period of use is avoided, and the product yield of the end cover assembly 100 is improved.

In some embodiments, the distance d3 between the valve plate 130 and the reinforcement 112 is in the range of: d3 is more than or equal to 4.5mm and less than or equal to 18.5mm. Specifically, the distance d3 between the valve block 130 and the reinforcement 112 may have a value of, but is not limited to, 4.5mm, 4.8mm, 5.0mm, 5.2mm, 5.6mm, 6.0mm, 6.5mm, 7.5mm, 8.4mm, 9.0mm, 10.5mm, 11.2mm, 12.3mm, 12.8mm, 13mm, 13.8mm, 14.5mm, 15.6mm, 16mm, 16.7mm, 17.5mm, 18mm, 18.5mm, etc.

It is understood that the distance between the valve block 130 and the reinforcement portion 112 may be a distance between an end of the valve block 130 adjacent to the reinforcement portion 112 and an end of the reinforcement portion 112 adjacent to the valve block 130 in the width direction of the top cover sheet 110.

In this embodiment, when the distance d3 between the valve block 130 and the reinforcing portion 112 satisfies the range of 4.5mm less than or equal to d3 less than or equal to 18.5mm, the distance between the valve block 130 and the reinforcing portion 112 is within a reasonable range, and the reinforcing portion 112 not only can strengthen the structural strength of the portion of the top cover sheet 110 close to the explosion proof hole 1113, but also can avoid interference caused by the arrangement of the valve block 130, thereby improving the assembly yield of the top cover sheet 110 and the lower plastic part 120. When the distance d3 between the explosion-proof valve plate 130 and the reinforcing portion 112 is greater than 18.5mm, the distance between the explosion-proof valve plate 130 and the reinforcing portion 112 is too large, and then the distance between the reinforcing portion 112 and the explosion-proof hole 1113 is too large, so that the structural strength of the portion of the top cover plate 110 close to the explosion-proof hole 1113 is weak, when the end cover assembly 100 is assembled in the energy storage device 300 and the air pressure in the energy storage device 300 reaches a certain value, the gas in the energy storage device 300 arches the top cover plate 110 while the explosion-proof valve plate 130 is exploded, so that the application of the energy storage device 300 in the energy storage module 400 is affected, that is, when a plurality of energy storage devices 300 are applied to the energy storage module 400, the top cover plate 110 is arched in a direction away from the electrode assembly 310 when the explosion-proof valve plate 130 of the end cover assembly 100 is exploded, so that the separator assembly 410 and the electrical connector 420 are arched in a direction away from the electrode assembly 310, and the electrical connection stability of the adjacent energy storage device 300 and the electrical connector 420 is affected. When the distance d3 between the valve block 130 and the reinforcing portion 112 is smaller than 4.5mm, the distance between the valve block 130 and the reinforcing portion 112 is too small, so that the reinforcing portion 112 easily interferes with the installation of the valve block 130, thereby reducing the assembly yield of the end cap assembly 100. Moreover, the lower plastic member 120 includes a lower plastic body 122 and an air permeable portion, where the orthographic projection of the air permeable portion on the second surface 1112 at least partially falls into the range of the anti-explosion valve plate 130, and the grooves 121 are arranged in one-to-one correspondence with the reinforcing portions 112, so that when the distance between the anti-explosion valve plate 130 and the reinforcing portions 112 is too small, the distance between the grooves 121 and the air permeable portion is too small, the grooves 121 easily interfere with the arrangement of the air permeable portion, and the assembly yield of the end cap assembly 100 is reduced.

In some embodiments, the lower plastic part 120 includes a lower plastic body 122 and two boss portions 126, the lower plastic body 122 has a third surface 1221 and a fourth surface 1222 that are disposed opposite to each other, the third surface 1221 is disposed opposite to the second surface 1112, two boss portions 126 are disposed on the fourth surface 1222 of the lower plastic body 122 at intervals along a first direction, and the groove 121 is disposed between the two boss portions 126 and is disposed at intervals with the two boss portions 126, wherein the first direction is a length direction of the top cover sheet 110.

It will be appreciated that in the end cap assembly 100 provided in the embodiment of the present application, the first surface 1111, the second surface 1112, the third surface 1221 and the fourth surface 1222 are sequentially stacked.

It may be appreciated that the two boss portions 126 are disposed on the fourth surface 1222 of the lower plastic body 122 at intervals along the first direction, that is, the two boss portions 126 are disposed on the surface of the lower plastic body 122 facing away from the top cover sheet 110 at intervals along the first direction, that is, the two boss portions 126 are disposed on the surface of the lower plastic body 122 near the electrode assembly 310 at intervals along the first direction.

In this embodiment, the two boss portions 126 are disposed on the fourth surface 1222 of the lower plastic body 122 at intervals along the first direction, the groove 121 is located between the two boss portions 126, and the groove 121 forms a protruding strip 1211 in a region corresponding to the orthographic projection of the fourth surface 1222, so that when the end cap assembly 100 is assembled to the energy storage device 300 and the energy storage device 300 is impacted during transportation, the two boss portions 126 will abut against one side of the electrode assembly 310 facing the end cap assembly 100, so as to prevent the thinner protruding strip 1211 from being directly inserted into the electrode assembly 310 to damage the electrode assembly 310, thereby being beneficial to prolonging the service lives of the end cap assembly 100 and the energy storage device 300.

Referring to fig. 7 to 15, in some embodiments, the ratio of the width d4 of the explosion proof hole 1113 along the first direction to the length d5 of the reinforcement portion 112 along the first direction is in the range of: d4/d5 is more than or equal to 0.05 and less than or equal to 0.25. Specifically, the value of d4/d5 may be, but is not limited to, 0.05, 0.08, 0.09, 0.10, 0.12, 0.13, 0.14, 0.15, 0.17, 0.18, 0.20, 0.21, 0.22, 0.23, 0.24, 0.25, etc.

It will be appreciated that the width d4 of the explosion proof hole 1113 in the first direction is smaller than the length d5 of the reinforcement portion 112 in the first direction.

In this embodiment, when the ratio of the width d4 of the explosion-proof hole 1113 along the first direction to the length d5 of the reinforcing portion 112 along the first direction satisfies the range of 0.05+.d4/d5+.0.25, the reinforcing portion 112 can sufficiently improve the structural strength of the top cover sheet 110 along the first direction, so that the top cover sheet 110 can still remain flat after a period of use, improving the stability of the adhesion arrangement between the top cover sheet 110 and the lower plastic member 120, and improving the assembly yield of the end cover assembly 100. When the ratio of the width d4 of the explosion-proof hole 1113 along the first direction to the length d5 of the reinforcing portion 112 along the first direction is greater than 0.25, the ratio of the width d4 of the explosion-proof hole 1113 along the first direction to the length d5 of the reinforcing portion 112 along the first direction is too large, and when the value of the width d4 of the explosion-proof hole 1113 along the first direction is fixed, the length d5 of the reinforcing portion 112 along the first direction is too small, so that the structural strength of the top cover sheet 110 along the first direction is difficult to be improved by the reinforcing portion 112, collapse or arch of the top cover sheet 110 is easy to occur after a period of use, and the assembly yield of the end cover assembly 100 is reduced. When the ratio of the width d4 of the explosion-proof hole 1113 along the first direction to the length d5 of the reinforcing portion 112 along the first direction is smaller than 0.05, if the width d4 of the explosion-proof hole 1113 along the first direction is constant, the length d5 of the reinforcing portion 112 along the first direction is too large, and accordingly, the length of the groove 121 along the first direction is too large. The lower plastic part 120 includes a lower plastic body 122 and two boss portions 126 protruding from the surface of the lower plastic body 122 facing away from the top cover 110, wherein the two boss portions 126 are disposed on opposite sides of the lower plastic body 122 along a first direction at intervals, in other words, the groove 121 is disposed between the two boss portions 126, and an excessive length of the groove 121 along the first direction affects the disposition of the boss of the lower plastic part 120.

In some embodiments, the maximum diameter of the cylindrical portion 142 is D1, and the diameter of the first mounting hole 113 is D2, then the relationship is satisfied: D2-D1 is more than or equal to 0.9mm and less than or equal to 2.2mm. In other words, the diameter of the first mounting hole 113 is larger than the maximum diameter of the cylindrical portion 142. Specifically, the value of D2-D1 may be, but is not limited to, 0.9mm, 0.92mm, 0.98mm, 1.02mm, 1.07mm, 1.12mm, 1.15mm, 1.2mm, 1.25mm, 1.28mm, 1.3mm, 1.38mm, 1.45mm, 1.52mm, 1.6mm, 1.65mm, 1.75mm, 1.80mm, 1.85mm, 1.89mm, 1.9mm, 2.0mm, 2.05mm, 2.1mm, 2.2mm, and the like.

As can be appreciated, the maximum diameter of the cylindrical portion 142 may be, when the cylindrical portion 142 is formed by stacking a plurality of cylinders, the maximum diameter of the cylindrical portion 142 is the diameter of the largest one of the plurality of cylinders; alternatively, when the cylindrical portion 142 is formed by arranging a single regular cylinder, the maximum diameter of the cylindrical portion 142 may be the diameter of the cylinder.

It will be appreciated that the value of D2-D1 is the amount of assembly allowance for the mounting of the post 142 to the first mounting hole 113.

In the present embodiment, when the difference between the diameter D2 of the first mounting hole 113 and the maximum diameter D1 of the cylindrical portion 142 satisfies the range: when D2-D1 is smaller than or equal to 0.9mm and smaller than or equal to 2.2mm, a certain assembly allowance exists when the column part 142 penetrates through the first mounting hole 113. In the assembly process of the end cap assembly 100, the first flange portion 141 of the pole 140 passes through the second mounting hole 123 and is disposed in the sinking table 124, the sinking table 124 locates and limits the position of the pole 140, and the column portion 142 of the pole 140 passes through the first mounting hole 113, so that the inner side wall of the first mounting hole 113 contacts with the column portion 142 and is in short-circuit connection when the top cover sheet 110 is mounted, and the first inner side wall 1131 of the first mounting hole 113 is prevented from rubbing the column portion 142, so as to prevent metal fragments generated by rubbing from falling to the electrode assembly 310 and from being in short-circuit connection with the electrode assembly 310, thereby improving the safety performance of the end cap assembly 100 and the energy storage device 300. When the value of D2-D1 is greater than 2.2mm, the difference between the diameter D2 of the first mounting hole 113 and the maximum diameter D1 of the cylinder part 142 is excessively large, so that it is difficult for the seal 150 to fill the fitting allowance between the first mounting hole 113 and the cylinder part 142, thereby reducing the stability of the mounting of the pole 140 to the end cap assembly 100. When the value of D2-D1 is smaller than 0.9mm, the difference between the diameter D2 of the first mounting hole 113 and the maximum diameter D1 of the column portion 142 is too small, and during the assembly process of the end cap assembly 100, the inner side wall of the first mounting hole 113 is easy to contact with and short-circuit with the column portion 142, and the first inner side wall 1131 of the first mounting hole 113 may scratch the column portion 142, so that the probability that metal chips generated by scratch fall to the electrode assembly 310 and short-circuit with the electrode assembly 310 is increased, and the safety performance of the end cap assembly 100 and the energy storage device 300 is reduced.

In some embodiments, the difference between the width D4 of the groove 121 along the second direction (as shown by Y in fig. 13) and the width D3 of the reinforcement portion 112 along the second direction is in the range of: D4-D3 is more than or equal to 0.15mm and less than or equal to 1.25mm. Specifically, the difference between the width D4 of the groove 121 along the second direction and the width D3 of the reinforcement portion 112 along the second direction may be, but is not limited to, 0.15mm, 0.23mm, 0.28mm, 0.35mm, 0.42mm, 0.46mm, 0.55mm, 0.58mm, 0.63mm, 0.72mm, 0.76mm, 0.85mm, 0.94mm, 0.99mm, 1.0mm, 1.08mm, 1.15mm, 1.25mm, etc.

In this embodiment, when the difference between the width D4 of the groove 121 along the second direction and the width D3 of the reinforcing portion 112 along the second direction satisfies the range of 0.15mm ∈d4-d3 ∈1.25mm, the difference between the width D4 of the groove 121 along the second direction and the width D3 of the reinforcing portion 112 along the second direction is within a reasonable range, and the reinforcing portion 112 has a suitable play allowance in the groove 121, so that not only the relative positions of the lower plastic member 120 and the top cover sheet 110 can be limited, but also the requirement on the accuracy of assembling the end cover assembly 100 can be reduced, which is beneficial to improving the assembly efficiency of the end cover assembly 100. In addition, the reinforcing portion 112 and the groove 121 cooperate with each other to limit the relative positions of the lower plastic member 120 and the top cover sheet 110, so as to prevent the sealant nails 160 from interfering the liquid running portion 125, so that the liquid running portion 125 can work normally. Furthermore, during the assembly process of the end cap assembly 100, the first flange 141 of the pole 140 passes through the second mounting hole 123 and is disposed in the sinking platform 124, and the sinking platform 124 locates and limits the position of the pole 140; the post portion 142 of the pole 140 passes through the first mounting hole 113, and the diameter of the first mounting hole 113 is different from the diameter of the post portion 142, so that the relative position of the post portion 142 and the first mounting hole 113 can be adjusted by arranging the reinforcing portion 112 in the recess 121, thereby improving the structural stability of the pole 140 in the end cap assembly 100. When the difference between the width D4 of the groove 121 along the second direction and the width D3 of the reinforcing portion 112 along the second direction is greater than 1.25mm, the difference between the width D4 of the groove 121 along the second direction and the width D3 of the reinforcing portion 112 along the second direction is too large, so that the movable allowance of the reinforcing portion 112 in the groove 121 is larger, and the movement space of the reinforcing portion 112 relative to the groove 121 along the second direction is larger, so that it is difficult to limit the relative positions of the lower plastic member 120 and the top cover sheet 110, thereby affecting further assembly of the end cover assembly 100, increasing the requirement on the precision of assembling the end cover assembly 100, and reducing the assembly efficiency of the end cover assembly 100. When the difference between the width D4 of the groove 121 along the second direction and the width D3 of the reinforcing portion 112 along the second direction is smaller than 0.15mm, the difference between the width D4 of the groove 121 along the second direction and the width D3 of the reinforcing portion 112 along the second direction is too small, so that the movable allowance of the reinforcing portion 112 in the groove 121 is smaller, the requirement on the precision of assembling the end cover assembly 100 is improved, and the assembly efficiency of the end cover assembly 100 is reduced.

Referring to fig. 7 to 17, in some embodiments, the lower plastic part 120 includes a lower plastic body 122, the lower plastic body 122 has a third surface 1221 and a fourth surface 1222 disposed opposite to each other, the third surface 1221 and the second surface 1112 are disposed opposite to each other, and a ratio of a height H1 of the reinforcing portion 112 to a maximum depth H2 of the recess 121 along a direction in which the top cover sheet 110 and the lower plastic part 120 are stacked is in a range: H1/H2 is more than or equal to 0.4 and less than 1. Specifically, the values of H1/H2 may be, but are not limited to, 0.4, 0.42, 0.48, 0.52, 0.55, 0.58, 0.62, 0.65, 0.69, 0.72, 0.75, 0.79, 0.82, 0.85, 0.89, 0.92, 0.96, 0.99, and the like.

As can be appreciated, the height H1 of the reinforcement portion 112 is smaller than the maximum depth H2 of the groove 121 in the direction in which the top cover sheet 110 and the lower plastic member 120 are stacked.

In this embodiment, when the end cap assembly 100 satisfies the relationship 0.4+.h1/h2 < 1, the ratio of the height of the reinforcing portion 112 to the maximum depth of the groove 121 is within a reasonable range, and the reinforcing portion 112 has a suitable play allowance in the groove 121, so that the relative positions of the lower plastic member 120 and the top cap sheet 110 can be limited, the requirement on the precision of assembling the end cap assembly 100 can be reduced, and the assembly efficiency of the end cap assembly 100 can be improved. In addition, the reinforcing portion 112 and the groove 121 cooperate with each other to limit the relative positions of the lower plastic member 120 and the top cover sheet 110, so as to prevent the sealant nails 160 from interfering the liquid running portion 125, so that the liquid running portion 125 can work normally. When the value of H1/H2 is greater than or equal to 1, the height of the reinforcing portion 112 is greater than the maximum depth of the groove 121, and the groove 121 cannot be completely disposed and accommodate the reinforcing portion 112, so that a gap exists between the top cover plate 110 and the lower plastic member 120, and the end cover assembly 100 cannot be further assembled in the energy storage device 300. When the value of H1/H2 is equal to 1, the height of the reinforcing portion 112 is equal to the maximum depth of the groove 121, so that when the reinforcing portion 112 is disposed in the groove 121, the reinforcing portion 112 is just clamped in the groove 121, and the reinforcing portion 112 has no play allowance in the groove 121, which increases the difficulty of assembling the top cover sheet 110 on one side of the lower plastic member 120, and reduces the assembly efficiency of the end cover assembly 100. When the value of H1/H2 is smaller than 0.4, the ratio of the height of the reinforcing portion 112 to the maximum depth of the recess 121 is too small, so that the height of the reinforcing portion 112 is much smaller than the maximum depth of the recess 121, and when the reinforcing portion 112 is disposed in the recess 121, the reinforcing portion 112 easily falls off from the recess 121, so that the top cover sheet 110 and the lower plastic member 120 slide relatively, and the lower plastic member 120 interferes with the connection between the top cover sheet 110 and the housing 330, thereby reducing the assembly efficiency of the end cover assembly 100 and the energy storage device 300.

In some embodiments, the height H1 of the reinforcement portion 112 along the direction in which the top cover sheet 110 and the lower plastic member 120 are stacked is in the range of: h1 is more than or equal to 1.05mm and less than or equal to 2.65mm. Specifically, the height H1 of the stiffener 112 may have a value of, but is not limited to, 1.05mm, 1.10mm, 1.12mm, 1.16mm, 1.23mm, 1.28mm, 1.35mm, 1.39mm, 1.45mm, 1.56mm, 1.68mm, 1.75mm, 1.85mm, 1.95mm, 2.02mm, 2.09mm, 2.15mm, 2.2mm, 2.34mm, 2.38mm, 2.45mm, 2.52mm, 2.58mm, 2.65mm, and the like.

In this embodiment, when the height H1 of the reinforcing portion 112 satisfies the range 1.05mm and H1 is less than or equal to 2.65mm, the value of the height H1 of the reinforcing portion 112 is within a reasonable range, and the reinforcing portion 112 can be accommodated in the groove 121, so as to improve the structural strength of the top cover sheet 110 along the first direction and the structural strength of the lower plastic member 120 along the first direction. When the height H1 of the reinforcing portion 112 is greater than 2.65mm, the height of the reinforcing portion 112 is too great, and accordingly, the depth of the groove 121 is too great, the height of the raised line 1211 formed by the groove 121 in the area corresponding to the orthographic projection of the fourth surface 1222 is too great, so that when the end cap assembly 100 is assembled to the energy storage device 300 and the energy storage device 300 is impacted during transportation, the risk that the boss 126 is directly inserted into the electrode assembly 310 and damages the electrode assembly 310 is increased, and the safety performance of the end cap assembly 100 assembled to the energy storage device 300 is reduced. When the height H1 of the reinforcing portion 112 is smaller than 1.05mm, the height of the reinforcing portion 112 is too small, so that the structural strength of the top cover sheet 110 along the first direction is difficult to be improved by the reinforcing portion 112, and in addition, when the top cover sheet 110 is disposed on one side of the lower plastic member 120, the reinforcing portion 112 is easy to fall off from the groove 121, which then causes the top cover sheet 110 and the lower plastic member 120 to slide relatively, so that the lower plastic member 120 interferes with the connection between the top cover sheet 110 and the housing 330, and then reduces the assembly efficiency of the end cover assembly 100 and the energy storage device 300.

Referring to fig. 5 to 18, in some embodiments, an orthographic projection of the lower plastic part 120 on the second surface 1112 falls within a range of the second surface 1112; along the first direction, a distance L1 between an outer periphery of the orthographic projection of the second surface 1112 and an outer periphery of the second surface 1112 of the lower plastic member 120 is in a range of: l1 is more than or equal to 1.2mm and less than or equal to 2.4mm; along the second direction, a distance L2 between an outer periphery of the orthographic projection of the second surface 1112 and an outer periphery of the second surface 1112 of the lower plastic member 120 is in a range of: l2 is more than or equal to 1.2mm and less than or equal to 2.4mm; the first direction is a length direction of the top cover sheet 110, the second direction is a width direction of the top cover sheet 110, and the first direction intersects with the second direction.

It is understood that the front projection of the lower plastic part 120 on the second surface 1112 falls within the range of the second surface 1112, and the top cover sheet 110 may be protruded from the lower plastic part 120.

Specifically, in the first direction, the distance L1 between the front projected outer periphery of the second surface 1112 and the outer periphery of the second surface 1112 of the lower plastic member 120 may have a value of, but is not limited to, 1.2mm, 1.25mm, 1.30mm, 1.35mm, 1.40mm, 1.43mm, 1.48mm, 1.52mm, 1.62mm, 1.68mm, 1.72mm, 1.84mm, 1.92mm, 1.98mm, 2.0mm, 2.12mm, 2.18mm, 2.25mm, 2.34mm, 2.36mm, 2.4mm, and the like.

Specifically, in the second direction, the distance L2 between the forward projected outer periphery of the second surface 1112 and the outer periphery of the second surface 1112 of the lower plastic member 120 may have a value of, but is not limited to, 1.2mm, 1.25mm, 1.30mm, 1.35mm, 1.40mm, 1.43mm, 1.48mm, 1.52mm, 1.62mm, 1.68mm, 1.72mm, 1.84mm, 1.92mm, 1.98mm, 2.0mm, 2.12mm, 2.18mm, 2.25mm, 2.34mm, 2.36mm, 2.4mm, and the like.

In the embodiment of the present application, when the distance L1 between the front projected outer periphery of the second surface 1112 and the outer periphery of the second surface 1112 of the lower plastic member 120 along the first direction satisfies the range of 1.2mm less than or equal to L1 less than or equal to 2.4mm, the lower plastic member 120 does not protrude from the top cover sheet 110 in the first direction, and when the end cover assembly 100 is assembled to the energy storage device 300, the distance between the front projected outer periphery of the second surface 1112 and the outer periphery of the second surface 1112 of the lower plastic member 120 can be used to realize welding of the top cover sheet 110 and the housing 330, so as to avoid interference between the connection of the top cover sheet 110 and the housing 330 by the lower plastic member 120. Along the second direction, when the distance L2 between the front projected outer periphery of the second surface 1112 and the outer periphery of the second surface 1112 satisfies the range 1.2mm less than or equal to L2 less than or equal to 2.4mm, the lower plastic member 120 will not protrude from the top cover sheet 110 in the second direction, and when the end cover assembly 100 is assembled to the energy storage device 300, the distance between the front projected outer periphery of the second surface 1112 and the outer periphery of the second surface 1112 of the lower plastic member 120 may be used to realize the welding between the top cover sheet 110 and the housing 330, so as to avoid the interference between the lower plastic member 120 and the connection between the top cover sheet 110 and the housing 330.

Optionally, the lower plastic 120 has a first edge 1223 and a second edge 1224 disposed opposite each other along the first direction on an outer periphery of the orthographic projection of the second surface 1112, the outer periphery of the second surface 1112 has a third edge 1114 and a fourth edge 1115 disposed opposite each other along the first direction, the third edge 1114 is disposed adjacent to the first edge 1223, the fourth edge 1115 is disposed adjacent to the second edge 1224, and in some embodiments, a distance between the third edge 1114 and the first edge 1223 is equal to a distance between the fourth edge 1115 and the second edge 1224. In other embodiments, the distance between the third edge 1114 and the first edge 1223 is not equal to the distance between the fourth edge 1115 and the second edge 1224.

Optionally, the lower plastic 120 has a fifth edge 1225 and a sixth edge 1226 disposed opposite each other along the second direction at an outer periphery of the orthographic projection of the second surface 1112, the outer periphery of the second surface 1112 has a seventh edge 1116 and an eighth edge 1117 disposed opposite each other along the second direction, the seventh edge 1116 is disposed adjacent to the fifth edge 1225, the eighth edge 1117 is disposed adjacent to the sixth edge 1226, and in some embodiments, a distance between the seventh edge 1116 and the fifth edge 1225 is equal to a distance between the eighth edge 1117 and the sixth edge 1226. In other embodiments, the distance between the seventh edge 1116 and the fifth edge 1225 is not equal to the distance between the eighth edge 1117 and the sixth edge 1226.

Referring to fig. 5 to 20, in some embodiments, the end cap assembly 100 further includes a sealing member 150, the sealing member 150 is sleeved on the column portion 142, the top cap piece 110 has a first inner sidewall 1131 surrounding the first mounting hole 113, the lower plastic member 120 has a second inner sidewall 1231 surrounding the second mounting hole 123, and the sealing member 150 is respectively abutted against the first inner sidewall 1131 and the second inner sidewall 1231.

As can be appreciated, the inner side wall of the seal 150 abuts against the cylindrical portion 142, and the outer side wall of the seal 150 abuts against the first inner side wall 1131 and the second inner side wall 1231, respectively.

In this embodiment, the sealing member 150 is sleeved on the column portion 142, so as to prevent the column portion 142 from contacting the first mounting hole 113 and the second mounting hole 123, and further prevent the pole 140 from being in short-circuit connection with the top cover 110, so that the end cover assembly 100 can be further assembled in the energy storage device 300.

Optionally, in some embodiments, the sealing member 150 includes a second flange portion 151 and a penetrating portion 152 protruding from a surface of the second flange portion 151, the second flange portion 151 is located between the first flange portion 141 and the lower plastic member 120, the penetrating portion 152 is respectively abutted to the first inner sidewall 1131 and the second inner sidewall 1231, and the second flange portion 151 and the penetrating portion 152 are both sleeved on the periphery of the column portion 142, so that the pole 140 and the top cover sheet 110 are insulated.

As can be appreciated, the penetrating portion 152 is protruding from the surface of the second flange 151 facing the top cover sheet 110, and the penetrating portion 152 and the second flange 151 are sequentially disposed along the direction in which the top cover sheet 110 and the lower plastic member 120 are stacked.

It may be appreciated that the second flange 151 is located between the first flange 141 and the lower plastic member 120, and one surface of the second flange 151 abuts against a portion of the surface of the first flange 141 facing the lower plastic member 120, and the other surface of the second flange 151 abuts against a portion of the surface of the lower plastic member 120 facing the first flange 141.

In the assembly process of the end cap assembly 100 provided in this embodiment, the sealing member 150 is sleeved on the column portion 142 of the pole 140, the first flange portion 141 of the pole 140 passes through the second mounting hole 123 and is disposed in the sinking platform 124, and then the top cap piece 110 is disposed on one side of the lower plastic member 120 and is matched with the groove 121 through the reinforcing portion 112 to achieve spacing fixation. The two opposite surfaces of the second flange 151 of the sealing member 150 respectively abut against the lower plastic member 120 and the first flange 141, so as to avoid the first flange 141 from being connected with the top cover sheet 110 in a short circuit manner; further, the penetrating portion 152 abuts against the first inner sidewall 1131 and the second inner sidewall 1231, so as to prevent the column portion 142 from being connected to the top cover sheet 110 in a short circuit manner, and finally achieve the insulation between the pole 140 and the top cover sheet 110.

Optionally, in some embodiments, the end cap assembly 100 further includes an upper plastic member 170, the upper plastic member 170 is located on a surface of the top cap piece 110 facing away from the lower plastic member 120, and is sleeved on the periphery of the column portion 142, and an end portion of the penetrating portion 152 facing away from the second flange portion 151 abuts against the upper plastic member 170.

In this embodiment, the end of the penetrating portion 152 away from the second flange 151 abuts against the upper plastic member 170, that is, the upper plastic member 170 abuts against the penetrating portion 152, so as to prevent the top cover piece 110 and the lower plastic member 120 from sliding relatively, and prevent the first inner sidewall 1131 of the first mounting hole 113 from passing through the gap between the upper plastic member 170 and the penetrating portion 152, and prevent the top cover piece 110 from being electrically connected with the pole 140. In addition, when the end cap assembly 100 is assembled to the energy storage device 300, the side wall of the column portion 142 of the pole 140 is prevented from being directly electrically connected to the outside, so as to improve the safety performance of the energy storage device 300.

Referring to fig. 21 and 22, the present application further provides an electric device 500, where the electric device 500 includes: the energy storage device 300 provides power for the device body 510, and the device body 510 and the energy storage device 300 provided by the application.

In this embodiment, the energy storage device 300 has a high product yield and assembly yield, so that when the energy storage device 300 is applied to the electric device 500, a stable power supply can be provided for the device body 510, so that the electric device 500 can work stably.

The electric device 500 of the embodiment of the application may be, but is not limited to, a portable electronic device such as a mobile phone, a tablet computer, a notebook computer, a desktop computer, a smart bracelet, a smart watch, an electronic reader, a game console, and the like. And can also be vehicles such as automobiles, trucks, sedans, trucks, vans, motor cars, high-speed rails, electric automobiles and the like. In addition, various home appliances and the like are also possible. The powered device 500 of the embodiment of fig. 22 is an energy storage battery cabinet.

It should be understood that the powered device 500 in this embodiment is only one form of the powered device 500 applied by the energy storage device 300, and should not be construed as limiting the powered device 500 provided by the present application, or as limiting the powered device 500 provided by the various embodiments of the present application.

Reference in the specification to "an embodiment," "implementation" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the described embodiments of the application may be combined with other embodiments. Furthermore, it should be understood that the features, structures or characteristics described in the embodiments of the present application may be combined arbitrarily without any conflict with each other, to form yet another embodiment without departing from the spirit and scope of the present application.

Finally, it should be noted that the above-mentioned embodiments are merely for illustrating the technical solution of the present application and not for limiting the same, and although the present application has been described in detail with reference to the above-mentioned preferred embodiments, it should be understood by those skilled in the art that modifications and equivalents may be made to the technical solution of the present application without departing from the spirit and scope of the technical solution of the present application.

Claims

1. An end cap assembly, said end cap assembly comprising:

the top cover sheet comprises a body part and reinforcing parts, wherein the body part is provided with a first surface and a second surface which are arranged in a back-to-back mode, the body part is also provided with explosion-proof holes, the explosion-proof holes penetrate through the first surface and the second surface respectively, the reinforcing parts are arranged on the second surface, the number of the reinforcing parts is two, the two reinforcing parts are arranged on two sides of the explosion-proof holes along the width direction of the top cover sheet, and the reinforcing parts are convex rib parts which are arranged on the second surface in a protruding mode;

the lower plastic part is arranged on the second surface side of the top cover plate and is provided with a third surface and a fourth surface which are arranged in opposite directions, the third surface and the second surface are arranged in opposite directions, and the lower plastic part is provided with a groove positioned on the third surface and used for accommodating the reinforcing part;

The explosion-proof valve block seals the explosion-proof hole and is connected to the body part; and

the pole comprises a first flange part and a column body, wherein the first flange part is far away from the first surface than the column body, the top cover piece is provided with a first mounting hole penetrating through the first surface and the second surface, the lower plastic part is provided with a second mounting hole penetrating through the third surface and the fourth surface, the lower plastic part is further provided with a sinking table surrounding the periphery of the second mounting hole and located on the fourth surface, the first flange part is arranged in the sinking table, and the column body sequentially penetrates through the second mounting hole and the first mounting hole.

2. The end cap assembly of claim 1, wherein the reinforcement extends in a first direction, the reinforcement including a first end and a second end disposed opposite in the first direction; in a first direction: the range of the length d1 of the first end protruding out of the anti-explosion valve plate is as follows: the length d2 of the second end protruding out of the explosion-proof valve plate is in the range of 18 mm-86 mm, and d1 is smaller than or equal to: and d2 is more than or equal to 18mm and less than or equal to 86mm, wherein the first direction is the length direction of the top cover sheet.

3. The end cap assembly of claim 1, wherein a distance d3 between the valve block and the reinforcement is in the range of: d3 is more than or equal to 4.5mm and less than or equal to 18.5mm.

4. The end cap assembly of claim 2, wherein a ratio of a width d4 of the explosion vent in the first direction to a length d5 of the reinforcement in the first direction ranges from: d4/d5 is more than or equal to 0.05 and less than or equal to 0.25.

5. The end cap assembly of claim 1, wherein the maximum diameter of the cylindrical portion is D1 and the diameter of the first mounting hole is D2, then the relationship: D2-D1 is more than or equal to 0.9mm and less than or equal to 2.2mm.

6. The end cap assembly of claim 2, wherein a difference between a width D4 of the groove in the second direction and a width D3 of the reinforcement portion in the second direction ranges from: D4-D3 is more than or equal to 0.15mm and less than or equal to 1.25mm; wherein the second direction is a width direction of the top sheet, and the second direction intersects the first direction.

7. The end cap assembly of claim 1, wherein the lower plastic part comprises a lower plastic body having third and fourth surfaces disposed opposite each other, the third surface disposed opposite the second surface, and the ratio of the height H1 of the reinforcement to the maximum depth H2 of the groove in the direction in which the top cover sheet and the lower plastic part are disposed in a stacked manner ranges from: H1/H2 is more than or equal to 0.4 and less than 1.

8. The end cap assembly of claim 7, wherein the height H1 of the reinforcement portion along the direction in which the top cover sheet is stacked with the lower plastic part ranges from: h1 is more than or equal to 1.05mm and less than or equal to 2.65mm.

9. The end cap assembly of claim 7, wherein the lower plastic part further comprises two boss portions, the two boss portions are disposed on the fourth surface of the lower plastic body at intervals along a first direction, the groove is disposed between the two boss portions and is disposed at intervals with the two boss portions, respectively, wherein the first direction is a length direction of the top cover sheet.

10. The end cap assembly of claim 1, wherein an orthographic projection of the lower plastic piece on the second surface falls within the scope of the second surface; along the first direction, the distance L1 between the front projection outer periphery of the second surface and the outer periphery of the second surface of the lower plastic part ranges from: l1 is more than or equal to 1.2mm and less than or equal to 2.4mm; along the second direction, the distance L2 between the front projection outer periphery of the second surface and the outer periphery of the second surface of the lower plastic part ranges from: l2 is more than or equal to 1.2mm and less than or equal to 2.4mm; the first direction is the length direction of the top cover sheet, the second direction is the width direction of the top cover sheet, and the first direction and the second direction intersect.

11. The end cap assembly of claim 1, further comprising a seal member, wherein the seal member is disposed around the cylindrical portion, the top cap sheet has a first inner sidewall surrounding the first mounting hole, the lower plastic member has a second inner sidewall surrounding the second mounting hole, and the seal member is respectively abutted against the first inner sidewall and the second inner sidewall.

12. An energy storage device, the energy storage device comprising:

the end cap assembly of any one of claims 1 to 11;

an electrode assembly;

an adapter electrically connecting the electrode assembly and the end cap assembly; and

the shell is arranged on one side of the end cover assembly, which faces the adapter, and is connected with the end cover assembly and enclosed into a containing groove with the end cover assembly, and the containing groove is used for containing the electrode assembly and the adapter.

13. An energy storage module, characterized in that the energy storage module comprises:

a plurality of energy storage devices of claim 12;

the isolation plate assembly is arranged on one side of the energy storage device and is used for preventing a plurality of energy storage devices from being connected in a short circuit mode; and

The electric connecting pieces are arranged on one side, deviating from the energy storage device, of the isolation plate assembly, and the electric connecting pieces are used for electrically connecting the energy storage devices.

14. An electrical device, the electrical device comprising:

an equipment body; and

the energy storage device of claim 12, the energy storage device powering the apparatus body.