CN217788581U

CN217788581U - End cover assembly, battery monomer, battery and power consumption device

Info

Publication number: CN217788581U
Application number: CN202221428179.7U
Authority: CN
Inventors: 刘全兵; 杨萌; 杨丽美; 刘晓梅
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2022-06-09
Filing date: 2022-06-09
Publication date: 2022-11-11
Anticipated expiration: 2032-06-09

Abstract

The application relates to an end cover assembly, a battery monomer, a battery and an electric device. The end cap assembly includes an end cap, a sealing member, and a shield member. The end cover is provided with a liquid injection hole which penetrates through the end cover; the sealing component is connected to the end part of the end cover, which is far away from the electrode component of the battery monomer, and seals the liquid injection hole, and a first air flow channel is arranged between the sealing component and the end cover; the protection component is at least partially arranged in the liquid injection hole, a second air flow channel is arranged in the protection component, the second air flow channel comprises a first state and a second state, the second air flow channel is communicated with one side of the protection component, which is far away from the sealing component, and the first air flow channel in the first state, and the second air flow channel is closed in the second state. This application can prolong the life of end cover subassembly.

Description

End cover assembly, battery monomer, battery and power consumption device

Technical Field

The application relates to the technical field of batteries, in particular to an end cover assembly, a battery monomer, a battery and an electric device.

Background

The battery cell is widely used in electronic devices such as a mobile phone, a notebook computer, a battery car, an electric airplane, an electric ship, an electric toy car, an electric toy ship, an electric toy airplane, an electric tool, and the like. The battery monomer can include a cadmium-nickel battery monomer, a hydrogen-nickel battery monomer, a lithium ion battery monomer, a secondary alkaline zinc-manganese battery monomer and the like.

In addition to improving the electrochemical performance of the battery cell, the service life of the battery cell is a considerable problem in the development of battery technology. If the service life of the battery cell cannot be guaranteed, the battery cell cannot be used. Therefore, how to prolong the service life of the battery cell is a technical problem to be solved urgently in the battery technology.

SUMMERY OF THE UTILITY MODEL

The application provides an end cover assembly, single battery, battery and power consumption device, aims at extension end cover assembly's life, prolongs single battery's life from this.

In a first aspect, embodiments of the present application provide an end cap assembly that includes an end cap, a sealing member, and a protective member. The end cover is provided with a liquid injection hole which penetrates through the end cover; the sealing member is connected to the end part, away from the electrode assembly of the battery monomer, of the end cover and seals the liquid injection hole, and a first air flow channel is formed between the sealing member and the end cover; and the protection component is at least partially arranged in the liquid injection hole, a second air flow channel is arranged in the protection component, the second air flow channel comprises a first state and a second state, the second air flow channel is communicated with one side of the protection component, which is far away from the sealing component, and the first air flow channel in the first state, and the second air flow channel is closed in the second state.

From this, the sealing member of this application connects the tip that deviates from electrode subassembly of end cover, can seal and annotate the liquid hole, when end cover subassembly was applied to the battery monomer, can guarantee the free sealing performance of battery, reduces the risk that electrolyte was revealed. When the second airflow channel of the protection member is in the first state, the second airflow channel can guide the inert gas on the side, away from the sealing member, of the protection member to flow to the first airflow channel, and therefore the sealing performance of the liquid injection hole is convenient to detect. When the second airflow channel of the protection member is in the second state, the second airflow channel is closed, one side of the protection member, which is far away from the sealing member, and the first airflow channel can be disconnected, the risk that inert gas and electrolyte flow to the first airflow channel is reduced, the corrosion damage of the electrolyte to the sealing member is reduced, the sealing performance of the sealing member to the liquid injection hole is ensured, the service life of the end cover assembly can be prolonged, and the service life of a battery monomer is prolonged when the end cover assembly is applied to the battery monomer.

In some embodiments, a seal member includes a seal body and an extension; the sealing main body is connected to the end part of the end cover, which is far away from the electrode assembly, and seals the liquid injection hole; the extension piece is connected with the sealing main body, and at least part of the extension piece is positioned in the second air flow channel, wherein in the first state, a gap is formed between the protection component and the extension piece, so that the second air flow channel is communicated with one side of the protection component, which is far away from the sealing component, and the first air flow channel; in the second state, the protective member contacts the extending member to close the second airflow channel.

Thus, the extension piece of the present application extends relative to the seal body and into the shield member, and the state of the second airflow channel is regulated by the cooperation between the shield member and the extension piece.

In some embodiments, the extension comprises a first extension and a second extension; the first extending part is connected with the sealing main body and is positioned in the second airflow channel; and the second extension part is connected to one side of the first extension part, which is far away from the sealing main body, and the second extension part is positioned on one side of the protection member, which is far away from the sealing main body, and the projection of the second extension part is at least partially overlapped with the projection of the protection member along the axial direction of the liquid injection hole.

Therefore, the first extension part and the second extension part can be matched with the protection component, and the purpose of regulating and controlling the second airflow channel is achieved. The second extension can play the guard action to protective member, reduces protective member and in taking place inflation or shrink in-process, the risk that drops, improves the holistic stability of end cover.

In some embodiments, the shield member comprises a body portion and a first connection portion; the body part is arranged in the liquid injection hole and is arranged outside the first extension part in a surrounding manner; the first connecting part is connected to one side of the second extending part facing the main body part, wherein the second airflow channel penetrates through the main body part along the axial direction of the liquid injection hole and extends to the position between the main body part and the first connecting part.

Therefore, when the protective member shrinks, a gap is formed between the body part and the first connecting part, and the inert gas can flow into the gap from the space between the body part and the first connecting part, further flow into the space between the body part and the first extending part, and then flow into the first air flow channel. The inert gas flows to the second gas flow channel through multiple turning, so that the impact force of the inert gas on the sealing member can be reduced, and the connection stability between the sealing member and the end cover is ensured.

In some embodiments, there is a gap between the body portion and the first extension; it is possible to ensure that the inert gas smoothly flows into the first gas flow path.

In some embodiments, the shield member includes a body portion and a second connecting portion; the body part is arranged in the liquid injection hole; at least part of the second connecting part is arranged in the body part, wherein at least part of the second airflow channel is formed between the second connecting part and the body part; in the first state, a gap is formed between the body part and the second connecting part, so that the second air flow channel is communicated with one side of the protection component, which is far away from the sealing component, and the first air flow channel; in a second state, the body part is contacted with the second connecting part so as to seal the second airflow channel.

Therefore, the second airflow channel is opened by regulating and controlling a gap between the body part and the second connecting part; the regulating body part and the second connecting part foundation are used for closing the second airflow channel.

In some embodiments, the second gas flow passage comprises a first hole section and a second hole section which are arranged in sequence along the axial direction of the liquid injection hole, the first hole section is communicated with the second hole section and the first gas flow passage, the hole diameter of the first hole section is larger than that of the second hole section, and the second connecting part is arranged in the first hole section.

Thus, the bore diameter of the first bore section is larger than the bore diameter of the second bore section, a step surface can be formed between the first bore section and the second bore section, on which step surface the second connection is located, in other words, which step surface gives the second connection a supporting effect. In the process that deformation takes place at second connecting portion/this somatic part, reduce the risk that second connecting portion dropped, guarantee the holistic stability of end cover subassembly.

In some embodiments, at least a portion of the second connecting portion extends in the axial direction of the pour spout and through the body portion, and the second connecting portion is connected to the sealing member.

From this, the second connecting portion of this application are connected with sealing member, reduce the risk that the second connecting portion drops from the end cover subassembly to improve the holistic stability of end cover subassembly. The second connecting part penetrates through the body part along the axial direction of the liquid injection hole, and when at least one of the second connecting part and the body part shrinks, the inert gas can flow to the first air flow channel from the second air flow channel in time, so that the sealing performance of the liquid injection hole can be rapidly detected.

In some embodiments, the second connection portion includes a first sub-portion and a second sub-portion; the first sub-part is connected with the sealing component and penetrates through the body part; the second sub-part is connected to the side of the first sub-part, which is far away from the sealing component, and is positioned on the side of the body part, which is far away from the sealing component, wherein in a first state, a gap is formed between the body part and the second sub-part, so that the second air flow channel is communicated with the side, which is far away from the sealing component, of the protection component and the first air flow channel; in a second state, the main body part is in contact with the second sub-part so as to close the second airflow channel.

Therefore, when at least one of the body part and the second connecting part contracts, a gap is formed between the body part and the second sub-part, and the inert gas can flow into the gap between the body part and the second sub-part, further flow into the gap between the body part and the first sub-part and then flow into the first air flow channel. The inert gas flows to the second gas flow channel through multiple turning, so that the impact force of the inert gas on the sealing member can be reduced, and the connection stability between the sealing member and the end cover is ensured.

In some embodiments, the shield member includes a first end connected to the sealing member, the first end being an end of the shield member facing away from the axis of the pour hole; the first end includes a through hole communicating the first air flow channel and the second air flow channel.

Therefore, the end part of the protective member, which is far away from the axis of the liquid injection hole, is connected with the sealing member, so that the connection strength between the protective member and the sealing member can be improved, and the structural stability of the whole end cover assembly is ensured; and the first end is provided with a through hole, so that the inert gas flows from the first airflow channel to the second airflow channel to detect the sealing performance of the liquid injection hole.

In some embodiments, the guard member is in contact with the wall of the pour hole, the guard member including a first end, the first end being the end of the guard member that faces away from the axis of the pour hole; at least part of the sealing member is disposed at a distance from the first end in the axial direction of the pour hole.

Therefore, the protective component can be fixed on the end cover through the first end, and the protective component is not easy to fall off from the end cover; and first end and sealing member interval set up, and inert gas can directly flow to first air current channel by the second air current channel, is favorable to the timely detection to the sealing performance of notes liquid hole department.

In some embodiments, the guard member is an interference fit with the pour hole. The pre-tightening force is kept between the protective component and the hole wall of the liquid injection hole, and the protective component is not easy to fall off from the liquid injection hole into the battery monomer.

In some embodiments, the shield member includes a second end that is the end of the shield member that protrudes from the end cap. The second end protrudes out of the end cover, so that the inflow space of inert gas is increased, the inert gas can flow into the end cover quickly, and the detection efficiency of the sealing performance is improved.

In some embodiments, at least a portion of the second end is tapered, cylindrical, or frustoconical. Play the guide effect when the guard member assembles to annotating the liquid hole, be favorable to guard member's rapid Assembly.

In some embodiments, the protective member is an inflatable structure. The protective member may be integrally provided as an expansion structure body, which realizes the circulation of inert gas and reduces the risk of the inflow of the electrolyte by utilizing its own contraction and/or expansion properties.

In some embodiments, at least a portion of the protective member is a breathable structure. The inert gas can flow to the first gas flow passage through the shield member, thereby improving the efficiency of detecting the sealing performance.

In a second aspect, the present application provides a battery cell comprising an end cap assembly according to any embodiment of the first aspect of the present application.

In a third aspect, the present application provides a battery comprising a battery cell as in the embodiments of the second aspect of the present application.

In a fourth aspect, the present application provides an electric device comprising a battery as in the embodiments of the third aspect of the present application. The battery is used for providing electric energy.

Drawings

Features, advantages and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

fig. 2 is an exploded schematic view of a battery provided in some embodiments of the present application;

fig. 3 is a schematic structural view of the battery module shown in fig. 2;

fig. 4 is an exploded schematic view of a battery cell provided in some embodiments of the present application;

FIG. 5 is a schematic structural view of an end cap assembly provided by some embodiments of the present application;

FIG. 6 is a schematic structural view of a guard member provided in accordance with certain embodiments of the present application;

FIG. 7 is an enlarged partial view of the second gas flow passage at A in the end cap assembly of FIG. 5 in a first state;

FIG. 8 is an enlarged partial view of the second air flow passage at A in the end cap assembly of FIG. 5 in a second condition;

FIG. 9 is another enlarged partial schematic view at A of the second air flow passage in the end cap assembly of FIG. 5 in a first state;

FIG. 10 is another enlarged, fragmentary view of a second air flow passage at A in the endcap assembly of FIG. 5 in a second state;

FIG. 11 is a further enlarged, fragmentary view of a second air flow passage at A in the end cap assembly of FIG. 5 in a second condition;

FIG. 12 is a further enlarged partial schematic view of the second gas flow passage at A in the end cap assembly of FIG. 5 in the first state;

FIG. 13 is a further enlarged partial view of the second air flow passage at A in the end cap assembly of FIG. 5 in the second state;

FIG. 14 is a further enlarged partial view of the second air flow passage at A in the end cap assembly of FIG. 5 in a second state;

FIG. 15 is a further enlarged partial schematic view of the second air flow passage at A in the end cap assembly of FIG. 5 in the first state;

FIG. 16 is a further enlarged, fragmentary view of the second air flow passage at A in the end cap assembly of FIG. 5 in a second condition;

FIG. 17 is a further enlarged partial schematic view of the second air flow passage at A in the end cap assembly of FIG. 5 in the first condition;

FIG. 18 is a further enlarged partial view of the second air flow passage at A in the end cap assembly of FIG. 5 in the first state;

FIG. 19 is a further enlarged, fragmentary view of the second air flow passage at A in the end cap assembly of FIG. 5 in a second condition;

FIG. 20 is a further enlarged partial schematic view at A of the second air flow passage in the end cap assembly of FIG. 5 in a second state.

The figures are not necessarily to scale.

The various reference numbers in the figures:

x, axial direction;

1. a vehicle; 2. a battery; 3. a controller; 4. a motor; 5. a box body; 501. a first tank portion; 502. a second tank portion; 503. an accommodating space; 6. a battery module; 7. a battery cell; 10. an electrode assembly; 20. a housing assembly; 30. a housing; 40. an end cap assembly; 41. an end cap; 411. a liquid injection hole; 4111. a hole wall; 412. an end portion; 413. an electrode terminal; 50. a sealing member; 51. a sealing body; 52. an extension member; 521. a first extension portion; 522. a second extension portion; 60. a guard member; 61. a body portion; 62. a first connection portion; 63. a second connecting portion; 631. a first sub-section; 632. a second sub-section; 64. a first end; 641. a through hole; 65. a second end; 70. a first air flow passage; 80. a second airflow channel; 81. a first bore section; 82. a second bore section.

Detailed Description

Embodiments of the present application will be described in further detail with reference to the drawings and examples. The following detailed description of the embodiments and the accompanying drawings are provided to illustrate the principles of the application and are not intended to limit the scope of the application, i.e., the application is not limited to the described embodiments.

In the description of the present application, it is to be noted that, unless otherwise specified, "a plurality" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," and the like, indicate an orientation or positional relationship that is merely for convenience in describing the application and to simplify the description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the application. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. "vertical" is not strictly vertical, but is within the tolerance of the error. "parallel" is not strictly parallel but within the tolerance of the error.

The following description is given with the directional terms as they are used in the drawings and not intended to limit the specific structure of the present application. In the description of the present application, it is also to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; may be directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the present application can be understood as appropriate by one of ordinary skill in the art.

In the present application, the battery cell may include 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, which is not limited in the embodiments of the present application. The battery cell may be a cylinder, a flat body, a rectangular parallelepiped, or other shapes, which is not limited in the embodiments of the present application. The battery cells are generally divided into three types in an encapsulation manner: the cylindrical battery monomer, the square battery monomer and the soft package battery monomer are not limited in the embodiment of the application.

Reference to a battery in embodiments of the present application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in the present application may include a battery module or a battery pack, etc. Batteries generally include a case for enclosing one or more battery cells. The box can avoid liquid or other foreign matters to influence the charging or discharging of battery monomer.

The battery monomer comprises an electrode assembly and electrolyte, wherein the electrode assembly comprises a positive plate, a negative plate and an isolating membrane. The battery cell mainly depends on metal ions moving between the positive plate and the negative plate to work. The positive plate comprises a positive current collector and a positive active substance layer, wherein the positive active substance layer is coated on the surface of the positive current collector, the current collector which is not coated with the positive active substance layer protrudes out of the current collector which is coated with the positive active substance layer, and the current collector which is not coated with the positive active substance layer is laminated to be used as a positive electrode lug. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate, or the like. The negative plate comprises a negative current collector and a negative active substance layer, the negative active substance layer is coated on the surface of the negative current collector, the current collector which is not coated with the negative active substance layer protrudes out of the current collector which is coated with the negative active substance layer, and the current collector which is not coated with the negative active substance layer is laminated to be used as a negative pole tab. The material of the negative electrode collector may be copper, and the negative electrode active material may be carbon, silicon, or the like. The material of the diaphragm can be PP or PE, etc. In addition, the electrode assembly may have a winding structure or a lamination structure, and the embodiment of the present application is not limited thereto.

The battery monomer includes shell subassembly, and shell subassembly includes end cover subassembly and casing, and after end cover and the casing of end cover subassembly are connected, can inject electrolyte into battery monomer through annotating the liquid hole on the end cover. After the electrolyte is injected, the injection hole needs to be sealed. In order to facilitate detection of the sealing performance, inert gas is generally injected into the battery cell, and whether the sealing performance is good or not is judged by detecting whether the inert gas leaks from the liquid injection hole. Herein, the inert gas may include argon, helium, and the like.

The inventors found that the liquid filling hole is usually sealed by the sealing member, but as the service life of the battery cell is prolonged, the sealing member is often corroded by the electrolyte, and the sealing performance of the sealing member at the liquid filling hole is deteriorated, so that the electrolyte may leak out of the battery cell, and the service life of the battery cell is reduced.

In view of this, the inventors propose an end cap assembly for a battery cell, the end cap assembly including a sealing member capable of sealing a liquid injection hole, and a protective member capable of expanding or contracting so that gas can flow to a joint of the sealing member and an end cap when the sealing performance is checked; when need not to detect the leakproofness, the risk that gas and electrolyte flow to the junction of sealing member and end cover can be reduced to a certain extent to the guard member to reduce the corruption risk of electrolyte to sealing member, improve the life of end cover subassembly.

The technical scheme described in the embodiment of the application is suitable for the battery monomer, the battery and the electric device using the battery

The electric device can be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, an electric tool and the like. The vehicle can be a fuel oil vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle or a range extending vehicle and the like; spacecraft include aircraft, rockets, space shuttles, spacecraft, and the like; electric toys include stationary or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric airplane toys, and the like; the electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and electric tools for railways, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, electric impact drills, concrete vibrators, and electric planers. The embodiment of the present application does not particularly limit the above power utilization apparatus.

For convenience of explanation, the following embodiments will be described by taking an electric device as an example of a vehicle.

Fig. 1 is a schematic structural diagram of a vehicle according to some embodiments of the present disclosure. As shown in fig. 1, a battery 2 is provided inside a vehicle 1, and the battery 2 may be provided at the bottom or the head or the tail of the vehicle 1. The battery 2 may be used for power supply of the vehicle 1, and for example, the battery 2 may serve as an operation power source of the vehicle 1.

The vehicle 1 may further comprise a controller 3 and a motor 4, the controller 3 being adapted to control the battery 2 to power the motor 4, e.g. for start-up, navigation and operational power demands while driving of the vehicle 1.

In some embodiments of the present application, the battery 2 may be used not only as an operating power source of the vehicle 1, but also as a driving power source of the vehicle 1, instead of or in part of fuel or natural gas, to provide driving power for the vehicle 1.

Fig. 2 is an exploded view of a battery according to some embodiments of the present disclosure. As shown in fig. 2, the battery 2 includes a case 5 and a battery cell (not shown in fig. 2) accommodated in the case 5.

The case 5 is used for accommodating the battery cells, and the case 5 may have various structures. In some embodiments, the box body 5 may include a first box body portion 501 and a second box body portion 502, the first box body portion 501 and the second box body portion 502 cover each other, and the first box body portion 501 and the second box body portion 502 together define a receiving space 503 for receiving a battery cell. The second casing portion 502 may be a hollow structure with one open end, the first casing portion 501 is a plate-shaped structure, and the first casing portion 501 covers the open side of the second casing portion 502 to form the casing 5 with the accommodating space 503; the first tank 501 and the second tank 502 may be hollow structures with one side open, and the open side of the first tank 501 may cover the open side of the second tank 502 to form the box 5 with the accommodating space 503. Of course, the first tank portion 501 and the second tank portion 502 may be various shapes, such as a cylinder, a rectangular parallelepiped, and the like.

In order to improve the sealing property after the first casing portion 501 and the second casing portion 502 are connected, a sealing member, such as a sealant or a sealing ring, may be provided between the first casing portion 501 and the second casing portion 502.

If the first box portion 501 covers the top of the second box portion 502, the first box portion 501 may also be referred to as an upper box cover, and the second box portion 502 may also be referred to as a lower box body.

In the battery 2, one or more battery cells may be provided. If the number of the battery monomers is multiple, the multiple battery monomers can be connected in series or in parallel or in series-parallel, and the series-parallel refers to that the multiple battery monomers are connected in series or in parallel. The plurality of battery monomers can be directly connected in series or in parallel or in series-parallel, and the whole formed by the plurality of battery monomers is accommodated in the box body 5; of course, a plurality of battery cells may be connected in series, in parallel, or in series-parallel to form the battery module 6, and a plurality of battery modules 6 may be connected in series, in parallel, or in series-parallel to form a whole, and may be accommodated in the box 5.

Fig. 3 is a schematic structural view of the battery module shown in fig. 2. As shown in fig. 3, in some embodiments, there are a plurality of battery cells 7, and the plurality of battery cells 7 are connected in series or in parallel or in series-parallel to form the battery module 6. A plurality of battery modules 6 are connected in series or in parallel or in series-parallel to form a whole and are accommodated in the case.

The plurality of battery cells 7 in the battery module 6 may be electrically connected to each other through a bus member, so as to realize parallel connection, series connection, or parallel connection of the plurality of battery cells 7 in the battery module 6.

Fig. 4 is an exploded schematic view of a battery cell provided in some embodiments of the present application.

As shown in fig. 4, the battery cell 7 provided in the embodiment of the present application includes an electrode assembly 10 and a case assembly 20, and the electrode assembly 10 is accommodated in the case assembly 20.

In some embodiments, the housing assembly 20 may also be used to contain an electrolyte, such as an electrolyte. The housing assembly 20 may take a variety of configurations.

In some embodiments, the case assembly 20 may include a case 30 and an end cap assembly 40, the case 30 is a hollow structure with one side open, and the end cap assembly 40 covers the opening of the case 30 and forms a sealing connection to form a receiving cavity for receiving the electrode assembly 10 and an electrolyte.

The housing 30 may be in various shapes, such as a cylinder, a rectangular parallelepiped, etc. The shape of the case 30 may be determined according to the specific shape of the electrode assembly 10. For example, if the electrode assembly 10 is of a cylindrical structure, it may be optionally a cylindrical case; if the electrode assembly 10 has a rectangular parallelepiped structure, a rectangular parallelepiped case may be used.

In some embodiments, the end cap assembly 40 includes an end cap 41, and the end cap 41 covers the opening of the housing 30. The end cap 41 may have various structures, for example, the end cap 41 has a plate-shaped structure, a hollow structure with one end open, and the like. For example, in fig. 4, the housing 30 has a rectangular parallelepiped structure, the end cap 41 has a plate-shaped structure, and the end cap 41 covers an opening at the top of the housing 30.

The end cap 41 may be made of an insulating material (e.g., plastic) or a conductive material (e.g., metal). When the end cap 41 is made of a metal material, the end cap assembly 40 may further include an insulating member at a side of the end cap 41 facing the electrode assembly 10 to insulate and separate the end cap 41 from the electrode assembly 10.

In some embodiments, the end cap assembly 40 may further include an electrode terminal 413, the electrode terminal 413 being mounted to the end cap 41. The two electrode terminals 413 are defined as a positive electrode terminal and a negative electrode terminal, respectively, and both of the positive electrode terminal and the negative electrode terminal are used to be electrically connected to the electrode assembly 10 to output electric power generated from the electrode assembly 10.

In other embodiments, the housing assembly 20 may have other structures, for example, the housing assembly 20 includes a housing 30 and two end cap assemblies 40, the housing 30 has a hollow structure with two opposite open sides, and one end cap assembly 40 is correspondingly covered on one open side of the housing 30 and forms a sealing connection to form a containing cavity for containing the electrode assembly 10 and the electrolyte. In such a configuration, two electrode terminals 413 may be provided on one end cap assembly 40, while the electrode terminal 413 is not provided on the other end cap assembly 40, or one electrode terminal 413 may be provided on each of the two end cap assemblies 40.

In the battery cell 7, the electrode assembly 10 housed in the case assembly 20 may be one or more. Illustratively, in fig. 4, there are four electrode assemblies 10.

FIG. 5 is a schematic structural view of an end cap assembly provided by some embodiments of the present application; FIG. 6 is a schematic structural view of a guard member provided in accordance with certain embodiments of the present application; FIG. 7 is an enlarged partial schematic view of the endcap assembly of FIG. 5 at A in the first state; FIG. 8 is an enlarged partial view of the second air flow passage of the end cap assembly of FIG. 5 at A in a second state.

As shown in fig. 5-8, in some embodiments, the end cap assembly 40 includes an end cap 41, a seal member 50, and a shield member 60; the end cover 41 is provided with a liquid injection hole 411, and the liquid injection hole 411 penetrates through the end cover 41; the sealing member 50 is connected to the end part 412 of the end cover 41, which faces away from the electrode assembly of the battery cell, and seals the liquid injection hole 411, and a first air flow channel 70 is formed between the sealing member 50 and the end cover 41; at least a portion of the shielding member 60 is disposed in the liquid injection hole 411, and the shielding member 60 has a second air flow channel 80 therein, wherein the second air flow channel 80 includes a first state and a second state, in the first state, the second air flow channel 80 communicates with the first air flow channel 70 and a side of the shielding member 60 away from the sealing member 50, and in the second state, the second air flow channel 80 is closed.

The sealing member 50 is connected to the end cap 41, and mainly serves to seal the liquid injection hole 411, so that the inside of the battery cell is substantially in a sealed state, and the risk of electrolyte leakage is reduced. The sealing member 50 and the end cover 41 are provided with a first air flow passage 70 therebetween, and inert gas can flow to the first air flow passage 70, so that the sealing performance of the sealing member 50 and the end cover 41 can be judged by detecting the content of the inert gas outside the liquid injection hole 411.

The sealing member 50 and the end cap 41 may be connected in various manners, the sealing member 50 may be directly connected to the end cap 41, for example, by welding, or the sealing member 50 may be indirectly connected to the end cap 41, for example, by adding a sealing ring therebetween or by bonding with an adhesive. Depending on the connection method, the sealing member 50 may be made of different materials, for example, when the sealing member 50 is welded to the end cap 41, the sealing member 50 may be made of a metal material such as aluminum, aluminum alloy, etc.; when the sealing member 50 is bonded to the end cap 41, the sealing member 50 may be made of a metal material such as aluminum, aluminum alloy, or the like, or an organic polymer material such as polypropylene (PP), polyvinyl chloride (PVC), or the like.

At least part of the protection member 60 is disposed in the liquid injection hole 411, and when the end cap assembly 40 is applied to a single battery, the protection member 60 on the one hand plays a role of guiding the inert gas in the single battery to the first gas flow channel 70; on the other hand, serves to reduce the risk of electrolyte flowing to the junction of the sealing member 50 and the end cap 41.

Specifically, the guard member 60 has a second airflow passage 80 therein, and the guard member 60 can regulate the state of the second airflow passage 80 by undergoing deformation, such as contraction and/or expansion.

Illustratively, when the shielding member 60 is contracted, the second air flow channel 80 is opened, and the second air flow channel 80 is in the first state, which can communicate the side of the shielding member 60 facing away from the sealing member 50 with the first air flow channel 70, so that the inert gas can flow to the first air flow channel 70, and the sealing performance at the liquid injection hole 411 can be detected. Fig. 7 shows a schematic view of the second gas flow channel 80 in the first state, and the direction of the arrows in the figure indicates the direction of the inert gas flow.

When the protection member 60 expands, the second gas flow channel 80 is closed, the second gas flow channel 80 is in the second state, the side of the protection member 60 away from the sealing member 50 and the first gas flow channel 70 are disconnected, and the possibility that inert gas and electrolyte flow to the first gas flow channel 70 is reduced, so that the sealing member 50 is protected in the normal cycle charging and discharging process of the battery cell. Fig. 8 shows a schematic view of the second air flow channel 80 in a second state.

Alternatively, the protection member 60 and the sealing member 50 may be matched with each other to control the state of the second airflow channel 80.

According to the end cover assembly 40 of the embodiment of the application, the sealing member 50 is connected with the end part 412 of the end cover 41, which is away from the electrode assembly, so that the liquid injection hole 411 can be sealed, when the end cover assembly 40 is applied to a battery cell, the sealing performance of the battery cell can be ensured, and the risk of electrolyte leakage is reduced. When the second gas flow passage 80 of the shield member 60 is in the first state, the second gas flow passage 80 can guide the inert gas on the side of the shield member 60 facing away from the sealing member 50 to the first gas flow passage 70, so as to facilitate detection of the sealing performance of the liquid pouring hole 411. When the second gas flow channel 80 of the protection member 60 is in the second state, the second gas flow channel 80 is closed, the side of the protection member 60 away from the sealing member 50 and the first gas flow channel 70 can be disconnected, the risk that inert gas and electrolyte flow to the first gas flow channel 70 is reduced, corrosion damage to the sealing member 50 by the electrolyte is reduced, the sealing performance of the sealing member 50 to the liquid injection hole 411 is ensured, the service life of the end cap assembly 40 can be prolonged, and when the end cap assembly 40 is applied to a battery cell, the service life of the battery cell is prolonged.

The sealing member 50 according to the embodiment of the present application has various structures, for example, the sealing member 50 may not directly contact with the protection member 60, or may be engaged with the protection member 60, and the structure of the sealing member 50 will be described below.

With continued reference to fig. 8, in some embodiments, the sealing member 50 may include a sealing body 51. The seal body 51 is attached to the end cap 41 of the end cap 41 facing away from the electrode assembly and seals the pour hole 411. The shield member 60 is contracted and/or expanded to connect or disconnect the second air flow path 80, thereby detecting the sealing performance.

FIG. 9 is another enlarged partial schematic view at A of the second air flow passage in the end cap assembly of FIG. 5 in a first state; FIG. 10 is another enlarged partial view at A of the second air flow passage in the end cap assembly of FIG. 5 in a second state.

As shown in fig. 9 and 10, in order to improve the connection stability of the shield member 60 on the end cap 41 and reduce the risk of the shield member 60 falling, the structures of the shield member 60 and the sealing member 50 may be matched. In other embodiments, the sealing member 50 may include a sealing body 51 and an extension 52. The sealing body 51 is connected to the end part 412 of the end cap 41, which is away from the electrode assembly, and seals the liquid injection hole 411; and an extension 52 is connected to the seal body 51, at least a portion of the extension 52 being located within the second airflow passage 80. In the first state of the second air flow channel 80, a gap is formed between the protection member 60 and the extension piece 52, so that the second air flow channel 80 communicates the side of the protection member 60 facing away from the sealing member 50 and the first air flow channel 70; in the second state of the second airflow path 80, the shielding member 60 contacts the extending member 52 to close the second airflow path 80.

The extension 52 extends relative to the seal body 51 and into the guard member 60, and the state of the second air flow passage 80 is regulated by the cooperation between the guard member 60 and the extension 52.

Embodiments of the present application may enable the second airflow channel 80 to be opened or closed by the contraction and/or expansion of the protective member 60 itself. Illustratively, as shown in fig. 9, when the guard member 60 is retracted, there is a gap between the guard member 60 and the extension 52, the second air flow path 80 is open, and the second air flow path 80 is in the first state. As shown in FIG. 10, when the shield member 60 is expanded, the shield member 60 and the extension 52 are in contact with each other with substantially no gap therebetween, the second air flow path 80 is closed, and the second air flow path 80 is in the second state.

With continued reference to fig. 10, as some examples, the extension 52 may include a first extension 521. The first extension 521 is connected to the sealing body 51 and located in the second air flow channel 80. The first extension 521 cooperates with the protection member 60 to achieve the purpose of regulating the state of the second air flow channel 80. Since the first extension portion 521 is located in the second air flow channel 80, the occupied space of the first extension portion 521 and the protective member 60 as a whole is small, and when the end cap assembly is applied to a battery cell, the occupied space of the electrode assembly can be increased, thereby increasing the energy density of the battery cell.

FIG. 11 is a further enlarged partial schematic view at A of the second air flow passage in the end cap assembly of FIG. 5 in a second condition.

As further examples, as shown in fig. 11, the extension 52 may include a first extension 521 and a second extension 522; the first extension 521 is connected to the sealing body 51 and located in the second air flow channel 80; and a second extending part 522 connected to the side of the first extending part 521 away from the sealing main body 51, wherein the second extending part 522 is located on the side of the shielding member 60 away from the sealing main body 51, and the projection of the second extending part 522 at least partially overlaps the projection of the shielding member 60 along the axial direction X of the liquid pouring hole 411. In FIG. 11, the X-direction indicates the axial direction of the liquid inlet 411.

The first and

second extensions

521 and 522 may cooperate with the guard member 60 for the purpose of regulating the second airflow channel 80. The second extending portion 522 is located on a side of the protection member 60 away from the sealing main body 51, and the second extending portion 522 covers at least a portion of the protection member 60, and the second extending portion 522 can protect the protection member 60, so that the risk that the protection member 60 falls off in the expansion or contraction process is reduced, and the stability of the whole end cover is improved.

When the shield member 60 is expanded, the first and

second extensions

521 and 522 have a gap with the shield member 60, so that the second air flow passage 80 is opened; when the shield member 60 is contracted, at least one of the first and

second extensions

521 and 522 is in contact with the shield member 60, thereby closing the second air flow passage 80.

The protective member 60 of the embodiment of the present application has various structural forms, and the protective member 60 can be used in cooperation with the sealing member 50 to realize the state adjustment of the second airflow passage 80; the protection member 60 can also adjust the state of the second air flow path 80 by its own expansion or contraction performance, and the structural form of the protection member 60 will be described in detail below.

FIG. 12 is a further enlarged partial schematic view of the second gas flow passage at A in the end cap assembly of FIG. 5 in the first state; FIG. 13 is a further enlarged partial schematic view at A of the second air flow passage in the end cap assembly of FIG. 5 in a second condition.

As shown in fig. 12 and 13, in some embodiments, the configuration of the shield member 60 and the seal member 50 cooperate to effect adjustment of the condition of the second airflow passage 80. Specifically, the shielding member 60 may include a body portion 61 and a first connecting portion 62, the body portion 61 is disposed inside the liquid injection hole 411 and surrounds and is disposed outside the first extending portion 521; the first connecting portion 62 is connected to the side of the second extending portion 522 facing the main body 61, wherein the second airflow channel 80 penetrates the main body 61 along the axial direction X of the injection hole 411 and extends between the main body 61 and the first connecting portion 62.

At least one of the body portion 61 and the first connection portion 62 has a deformation function.

As some examples, the first connection portion 62 can be deformed, as shown in fig. 12, when the first connection portion 62 is contracted, the first connection portion 62 is contracted in a direction away from the body portion 61, a gap is generated between the body portion 61 and the first connection portion 62, and the inert gas can flow in between the body portion 61 and the first connection portion 62, further flow between the body portion 61 and the first extension portion 521, and then flow to the first gas flow channel 70. The inert gas flows to the first gas flow passage 70 through multiple times of diversion, so that the impact force of the inert gas on the sealing member 50 can be reduced, and the connection stability between the sealing member 50 and the end cover 41 can be ensured. As shown in fig. 13, when the first connection portion 62 expands, the first connection portion 62 expands toward the body portion 61, the first connection portion 62 and the body portion 61 are attached to each other, and the second air flow path 80 is closed.

FIG. 14 is a further enlarged partial schematic view at A of the second air flow passage in the end cap assembly of FIG. 5 in a second condition. Further, as shown in fig. 14, there may be a gap between the body portion 61 and the first extension 521, which is not affected by contraction and/or expansion.

As other examples, the body portion 61 can be deformed, when the body portion 61 is shrunk, the body portion 61 is shrunk to a direction away from the first connection portion 62, a gap is generated between the body portion 61 and the first connection portion 62, and the inert gas can flow in from between the body portion 61 and the first connection portion 62, further flow between the body portion 61 and the first extension portion 521, and then flow to the first gas flow channel 70. In this case, the body portion 61 and the first extension 521 may have a gap therebetween, which may not be affected by contraction and/or expansion. Of course, since the main body 61 itself has a contraction function, the gap may be generated when the main body 61 contracts.

As still other examples, the body portion 61 and the first connection portion 62 each have a deformation capability, and are capable of contracting and/or expanding.

FIG. 15 is a further enlarged partial schematic view of the second gas flow passage at A in the end cap assembly of FIG. 5 in the first state; FIG. 16 is a further enlarged partial schematic view at A of the second air flow passage in the end cap assembly of FIG. 5 in the second condition.

In other embodiments, as shown in fig. 15 and 16, the shield member 60 achieves conditioning of the second airflow passage 80 through its own contraction and/or expansion properties. Specifically, the guard member 60 includes a body portion 61 and a second connecting portion 63; the body 61 is arranged in the liquid injection hole 411; and the second connection portion 63 is at least partially disposed within the body portion 61, wherein at least a portion of the second airflow passage 80 is formed between the second connection portion 63 and the body portion 61; in the first state, a gap is formed between the main body 61 and the second connecting portion 63, so that the second air flow channel 80 communicates the first air flow channel 70 and a side of the protection member 60 facing away from the sealing member 50; in the second state, the body portion 61 and the second connecting portion 63 are in contact, so that the second airflow channel 80 is closed.

At least one of the body portion 61 and the second connecting portion 63 has a deformation capability, and is capable of contracting and/or expanding.

Exemplarily, the second connection 63 has a contraction and/or expansion capacity; when the second connection portion 63 is contracted, the second connection portion 63 is contracted in a direction away from the body portion 61, a gap is generated between the body portion 61 and the second connection portion 63, and the inert gas can flow in from between the body portion 61 and the second connection portion 63 and then to the first gas flow passage 70. In this case, the body portion 61 may not have the contraction and/or expansion capability, and the body portion 61 may contact the hole wall 4111 of the liquid filling hole 411 to fix the shielding member 60 to the end cap 41.

Alternatively, the main body 61 has a contraction and/or expansion capability, when the main body 61 contracts, the main body 61 contracts in a direction away from the second connection portion 63, a gap is generated between the main body 61 and the second connection portion 63, and the inert gas can flow in between the main body 61 and the second connection portion 63 and then flow to the first gas flow passage 70.

Alternatively, the body portion 61 and the second connecting portion 63 each have a deformation capability, and are capable of contracting and/or expanding. In this case, when the main body 61 is contracted, a gap may be formed between the main body 61 and the hole wall 4111 of the liquid inlet 411, the main body 61 may be separated from the lid 41, and the main body 61 and the seal member 50 may be connected to each other to reduce the risk of separation of the shield member 60. Of course, when the main body 61 is contracted, there may be no gap between the main body 61 and the hole wall 4111 of the liquid inlet 411, and in this case, the main body 61 may not be connected to the seal member 50.

With continued reference to fig. 15 and 16, as some examples, the second air flow channel 80 includes a first hole section 81 and a second hole section 82 arranged in sequence along the axial direction X of the liquid injection hole 411, the first hole section 81 connects the second hole section 82 and the first air flow channel 70, the hole diameter of the first hole section 81 is larger than that of the second hole section 82, and the second connection portion 63 is arranged in the first hole section 81. The first bore section 81 has a larger bore diameter than the second bore section 82, and a step surface can be formed between the first bore section 81 and the second bore section 82, on which step surface the second connection portion 63 is located, in other words, which step surface gives a supporting effect to the second connection portion 63. In the process of deformation of the second connecting portion 63 and/or the body portion 61, the risk that the second connecting portion 63 falls is reduced, and the stability of the whole end cover assembly is ensured.

Of course, the second connection portion 63 may be further connected to the sealing member 50 in order to further improve the stability of the entire end cap assembly.

FIG. 17 is a further enlarged partial schematic view at A of the second air flow passage in the end cap assembly of FIG. 5 in the first condition.

As another example, as shown in FIG. 17, at least a portion of the second connecting portion 63 extends in the axial direction X of the pour hole 411 and through the body portion 61, and the second connecting portion 63 is connected to the sealing member 50. The second connecting portion 63 is connected to the sealing member 50, so that the risk that the second connecting portion 63 falls off from the end cap assembly is reduced, and the overall stability of the end cap assembly is improved. The second connecting part 63 penetrates through the main body part 61 along the axial direction X of the liquid injection hole 411, and when at least one of the second connecting part 63 and the main body part 61 contracts, the inert gas can flow from the second gas flow channel 80 to the first gas flow channel 70 in time, so that the sealing performance at the liquid injection hole 411 can be detected quickly.

FIG. 18 is a further enlarged partial view of the second air flow passage at A in the end cap assembly of FIG. 5 in the first state; FIG. 19 is a further enlarged partial schematic view of the second air flow passage at A in the end cap assembly of FIG. 5 in the second state.

As shown in fig. 18 and 19, further, the second connection portion 63 includes a first sub-portion 631 and a second sub-portion 632; the first sub-portion 631 is connected to the sealing member 50 and penetrates the body portion 61; the second sub-portion 632 is connected to a side of the first sub-portion 631, which faces away from the sealing member 50, and is located on a side of the main body portion 61, which faces away from the sealing member 50, wherein in the first state, a gap is formed between the main body portion 61 and the second sub-portion 632, so that the second air flow channel 80 communicates a side of the shielding member 60, which faces away from the sealing member 50, with the first air flow channel 70; in the second state, the main body 61 contacts the second sub-portion 632 to close the second airflow channel 80.

When at least one of the body portion 61 and the second connecting portion 63 contracts, a gap is formed between the body portion 61 and the second sub-portion 632, and the inert gas can flow in from between the body portion 61 and the second sub-portion 632, further flow between the body portion 61 and the first sub-portion 631, and then flow to the first gas flow channel 70. The inert gas flows to the first gas flow channel 70 through multiple turns, so that the impact force of the inert gas on the sealing member 50 can be reduced, and the connection stability between the sealing member 50 and the end cover can be ensured.

With continued reference to FIG. 19, to further reduce the risk of the shield member 60 becoming dislodged from the end cap 41 during contraction and/or expansion, the shield member 60 and the sealing member 50 are connected. In some embodiments, the guard member 60 includes a first end 64 connected with the sealing member 50, the first end 64 being the end of the guard member 60 facing away from the axis of the pour hole 411; the first end 64 includes a through hole 641 communicating the first and second

air flow passages

70 and 80. The end of the shield member 60 that faces away from the axis of the pour hole 411 is connected to the seal member 50, so that the connection strength between the two can be improved, thereby ensuring the structural stability of the whole end cap assembly; and the through hole 641 is opened at the first end 64, which is beneficial to the inert gas flowing from the first gas flow channel 70 to the second gas flow channel 80 for detecting the sealing performance at the liquid injection hole 411.

FIG. 20 is a further enlarged partial schematic view of the second air flow passage at A in the end cap assembly of FIG. 5 in the second state.

In other embodiments, as shown in FIG. 20, the guard member 60 is in contact with the hole wall 4111 of the pour hole 411, the guard member 60 including a first end 64, the first end 64 being the end of the guard member 60 that faces away from the axis of the pour hole 411; at least a portion of the sealing member 50 is disposed at a distance from the first end 64 in the axial direction X of the pour hole 411. The guard member 60 may be fixed to the end cap 41 through the first end 64, and the guard member 60 is not easily detached from the end cap 41; and the first end 64 and the sealing member 50 are arranged at intervals, the inert gas can directly flow from the second gas flow channel 80 to the first gas flow channel 70, and timely detection of the sealing performance at the liquid injection hole 411 is facilitated.

With continued reference to fig. 20, in some embodiments, the shielding member 60 may be in an interference fit with the liquid filling hole 411, and a pre-tightening force is maintained between the shielding member 60 and the hole wall 4111 of the liquid filling hole 411, so that the shielding member 60 is not easy to fall off from the liquid filling hole 411 into the battery cell. Further, since the guard member 60 is in close contact with the hole wall 4111 of the liquid inlet 411, the possibility of debris or dust entering between the guard member 60 and the hole wall 4111 of the liquid inlet 411 can be reduced. The protective member 60 and the liquid injection hole 411 are connected in an interference fit manner, so that the assembly process of the protective member and the liquid injection hole is simple, convenient and efficient, and the assembly work efficiency is improved.

The guard member 60 may be a flexible structure, the guard member 60 is pressed into the pour hole 411 by pressing the guard member 60, and the guard member 60 may be adapted to the shape of the hole wall 4111 of the pour hole 411 by the self elastic restoring force of the guard member 60.

With continued reference to fig. 20, in some embodiments, the protection component 60 includes a second end 65, and the second end 65 is an end of the protection component 60 protruding from the end cap 41. The second end 65 protrudes out of the end cover 41, so that the inflow space of inert gas is increased, the inert gas can flow in quickly, and the detection efficiency of the sealing performance is improved. And when the shield member 60 is in interference fit with the pour hole 411, the second end 65 protrudes from the end cap 41, which is beneficial to improving the sealing performance between the shield member 60 and the pour hole 411.

Further, at least a portion of the second end 65 is tapered, cylindrical, or truncated cone-shaped, and serves as a guide when the shield member 60 is fitted to the pour hole 411, facilitating quick fitting of the shield member 60.

In other embodiments, the surface of the protective member 60 may be flush with the surface of the end cap 41, so as to reduce the overall space occupied by the end cap assembly, and increase the space occupied by the electrode assembly when the end cap assembly is applied to a battery cell, thereby increasing the energy density of the battery cell.

At least a portion of the protective member 60 of the present embodiment has a contraction and/or expansion property, and it may be provided as an expansion structure that can be subjected to a form change according to a temperature change. In some embodiments, the protective member 60 may be integrally provided as an expansion structure, and uses its own contraction and/or expansion properties to achieve circulation of inert gas and reduce the risk of inflow of the electrolyte.

As some examples, the expansion structure may be an organic polymer material that contracts and/or expands when subjected to a change in temperature. Further, the expansion coefficient of the expanded structure was 1.0 × 10 ^-4 /℃～1.0×10 ^-2 The expansion structure has moderate expansion performance within the range, and can not excessively extrude the liquid injection hole 411, the sealing member 50 and the like while generating a gap, thereby ensuring the structural stability of the whole end cover assembly.

As other examples, the expansion structure may also be a memory alloy structure that contracts and/or expands when subjected to a change in temperature.

In some embodiments, at least a portion of the shield member 60 may be a gas permeable structure, and the inert gas can flow through the shield member 60 to the first gas flow channel 70, thereby improving the efficiency of detecting the sealing performance.

Specifically, the permeability of the protective member 60 to the electrolyte is smaller than that to the inert gas, that is, the protective member 60 can reduce the risk of the electrolyte flowing into the first gas flow channel 70 through the protective member 60 to some extent on the basis of ensuring the inert gas to flow to the first gas flow channel 70.

Illustratively, the pressure differential of the gas permeable structure is 1.013 x 10 ⁵ Pa, temperature of 25 deg.C, permeability coefficient to inert gas of 1.0 × 10 ^-17 m ² /(s*Pa)～1.0×10 ^-12 m ² /(s*Pa)。

Illustratively, the pressure differential of the gas permeable structure is 1.013 x 10 ⁵ Pa, temperature of 25 deg.C, permeability coefficient to electrolyte of 1.0 × 10 ^-14 g/(cm*s*Pa)～1.0×10 ^-12 g/(cm*s*Pa)。

As shown in fig. 5 to 8, as a specific embodiment of the present application, the end cap assembly 40 includes an end cap assembly 40 including an end cap 41, a sealing member 50, and a shield member 60; the end cover 41 is provided with a liquid injection hole 411, and the liquid injection hole 411 penetrates through the end cover 41; the sealing member 50 is connected to the end of the end cap 41 facing away from the electrode assembly of the battery cell and seals the liquid injection hole 411, and a first air flow channel 70 is formed between the sealing member 50 and the end cap 41; at least a part of the shielding member 60 is disposed in the liquid injection hole 411, and the shielding member 60 has a second air flow passage 80 therein, wherein the second air flow passage 80 includes a first state and a second state, in the first state, the second air flow passage 80 communicates the side of the shielding member 60 away from the sealing member 50 and the first air flow passage 70, and in the second state, the second air flow passage 80 is closed. The protective member 60 may be integrally provided as an expanded structure. The opening or closing of the second air flow path 80 is achieved by the contraction and/or expansion of the guard member 60.

While the present application has been described with reference to preferred embodiments, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the present application, and particularly, features described in connection with the embodiments may be combined in any manner as long as there is no structural conflict. The present application is not intended to be limited to the particular embodiments disclosed herein but is to cover all embodiments that may fall within the scope of the appended claims.

Claims

1. An end cap assembly for a battery cell (7), the end cap assembly (40) comprising:

the end cover (41) is provided with a liquid injection hole (411), and the liquid injection hole (411) penetrates through the end cover (41);

a sealing member (50) that is connected to an end portion (412) of the end cap (41) that faces away from the electrode assembly (10) of the battery cell (7) and seals the liquid injection hole (411), the sealing member (50) and the end cap (41) having a first air flow passage (70) therebetween; and

a shielding member (60) at least partially disposed in the pour hole (411), the shielding member (60) having a second air flow passage (80) therein,

wherein the second air flow channel (80) comprises a first state and a second state, in the first state, the second air flow channel (80) communicates the first air flow channel (70) and a side of the protection member (60) facing away from the sealing member (50), and in the second state, the second air flow channel (80) is closed.

2. An end cap assembly according to claim 1, wherein the sealing member (50) comprises:

a sealing body (51) which is connected to an end portion (412) of the end cap (41) that faces away from the electrode assembly (10) and seals the liquid injection hole (411); and

an extension (52) connected to the seal body (51), at least a portion of the extension (52) being located within the second airflow channel (80),

wherein, in the first state, a gap is formed between the protection component (60) and the extension piece (52) so that the second air flow channel (80) is communicated with the first air flow channel (70) and one side of the protection component (60) facing away from the sealing component (50); in the second state, the guard member (60) contacts the extension (52) to close the second airflow passage (80).

3. The end cap assembly of claim 2, wherein the extension (52) comprises:

a first extension (521) connected to the sealing body (51) and located within the second air flow channel (80); and

and the second extending part (522) is connected to one side, which is far away from the sealing main body (51), of the first extending part (521), the second extending part (522) is positioned on one side, which is far away from the sealing main body (51), of the protection member (60), and the projection of the second extending part (522) is at least partially overlapped with the projection of the protection member (60) along the axial direction (X) of the liquid injection hole (411).

4. The end cap assembly of claim 3, wherein the guard member (60) comprises:

the body part (61) is arranged in the liquid injection hole (411) and is arranged outside the first extending part (521) in a surrounding way; and

a first connecting portion (62) connected to a side of the second extending portion (522) facing the body portion (61),

wherein the second airflow channel (80) penetrates through the body part (61) along the axial direction (X) of the liquid injection hole (411) and extends to the space between the body part (61) and the first connecting part (62).

5. An end cap assembly according to claim 4, wherein there is a gap between the body portion (61) and the first extension (521).

6. The end cap assembly of claim 1, wherein the shield member (60) comprises:

a body section (61) provided in the liquid injection hole (411); and

a second connecting portion (63) at least partially disposed within the body portion (61),

wherein at least part of the second air flow channel (80) is formed between the second connecting portion (63) and the body portion (61);

in the first state, a gap is formed between the body part (61) and the second connecting part (63) so that the second air flow channel (80) is communicated with the first air flow channel (70) and one side of the protection member (60) departing from the sealing member (50); in the second state, the body portion (61) and the second connecting portion (63) are in contact, so that the second airflow passage (80) is closed.

7. The end cap assembly according to claim 6, wherein the second gas flow passage (80) comprises a first hole section (81) and a second hole section (82) which are sequentially arranged along the axial direction (X) of the liquid injection hole (411), the first hole section (81) is communicated with the second hole section (82) and the first gas flow passage (70), the hole diameter of the first hole section (81) is larger than that of the second hole section (82), and wherein the second connecting part (63) is arranged in the first hole section (81).

8. An end cap assembly according to claim 6, wherein at least part of the second connecting portion (63) extends in the axial direction (X) of the pouring hole (411) and through the body portion (61), and the second connecting portion (63) is connected with the sealing member (50).

9. An end cap assembly according to claim 8, wherein the second connecting portion (63) comprises:

a first sub-section (631) connected to the sealing member (50) and penetrating the body section (61); and

a second sub-part (632) connected to a side of the first sub-part (631) facing away from the sealing member (50) and located on a side of the body part (61) facing away from the sealing member (50),

wherein, in the first state, a gap is formed between the main body part (61) and the second sub-part (632) so that the second air flow channel (80) is communicated with the first air flow channel (70) and one side of the protection component (60) facing away from the sealing component (50); in the second state, the main body (61) is in contact with the second sub-portion (632) to close the second airflow channel (80).

10. An end cap assembly according to any one of claims 1 to 9, wherein the shield member (60) comprises a first end (64) connected to the sealing member (50), the first end (64) being the end of the shield member (60) facing away from the axis of the pour hole (411); the first end (64) includes a through hole (641) communicating the first air flow channel (70) and the second air flow channel (80).

11. An end cap assembly according to any one of claims 1 to 9,

the guard member (60) is in contact with the hole wall (4111) of the pour hole (411), the guard member (60) comprising a first end (64), the first end (64) being the end of the guard member (60) facing away from the axis of the pour hole (411);

at least a part of the sealing member (50) is provided at a distance from the first end (64) in the axial direction (X) of the pour hole (411).

12. An end cap assembly according to any one of claims 1 to 9, wherein the guard member (60) is an interference fit with the pour hole (411).

13. An end cap assembly according to any one of claims 1 to 9, wherein the guard member (60) comprises a second end (65), the second end (65) being the end of the guard member (60) that protrudes from the end cap (41).

14. An end cap assembly according to claim 13, wherein at least part of the second end (65) is tapered, cylindrical or frusto-conical.

15. An end cap assembly according to any one of claims 1 to 9, wherein the guard member (60) is a thermally expanding structure.

16. An end cap assembly according to any one of claims 1 to 9, wherein at least part of the guard member (60) is a gas permeable structure.

17. A battery cell, comprising an end cap assembly (40) according to any one of claims 1 to 16.

18. A battery comprising a battery cell (7) according to claim 17.

19. An electric consumer, characterized in that it comprises a battery (2) according to claim 18, said battery (2) being intended to provide electric energy.