Battery cell, battery, and electric device

Abstract

The application discloses a battery monomer, a battery and a power utilization device. The battery monomer comprises a shell, an electrode terminal, a first blocking piece and a second blocking piece. The shell comprises a wall part, and the wall part has a lead-out hole; the electrode terminal is inserted into the lead-out hole along an axial direction of the electrode terminal, and the electrode terminal has a first recess part and a liquid injection hole connected along the axial direction, the liquid injection hole is located at the bottom of the first recess part, and in the radial direction of the electrode terminal, the radial dimension of the liquid injection hole is smaller than the radial dimension of the first recess part, and the first recess part is communicated with the inside of the shell through the liquid injection hole; the first blocking piece is at least partially arranged in the first recess part and is used for blocking the liquid injection hole; and the second blocking piece is at least partially inserted into the first recess part along the axial direction and is used for blocking the first recess part, and the second blocking piece holds the first blocking piece. In this way, the blocking effect of the liquid injection hole can be improved.

Description

[Technical Field]

[0001] This application relates to the field of battery technology, and in particular to battery cells, batteries, and electrical devices. [Background Technology]

[0002] With the development of battery technology, battery cells are being applied in more and more fields, gradually replacing traditional fossil fuels in the automotive power sector. Battery cells can store chemical energy and controllably convert it into electrical energy. In recyclable battery cells, the active materials can be reactivated through charging after discharge, allowing for continued use.

[0003] A single battery cell typically includes an electrode assembly, electrode terminals, a housing, and a sealing element. The housing houses the electrode assembly. The electrode assembly is electrically connected to the outside environment via the electrode terminals. The electrode terminals may have injection holes for injecting electrolyte into the housing. The sealing element is used to seal the injection holes. In existing battery cell structures, the sealing element's structure and function for sealing the injection holes are relatively simple, and its sealing effectiveness needs further improvement. [Summary of the Invention]

[0004] In view of the above problems, this application provides a battery cell, a battery, and an electrical device that can improve the sealing effect on the injection hole.

[0005] In a first aspect, this application provides a battery cell, which includes a casing, electrode terminals, a first sealing member, and a second sealing member. The casing includes a wall portion with an outlet hole. The electrode terminals are inserted into the outlet hole along the axial direction of the electrode terminals. The electrode terminals have a first recess and an injection hole connected along the axial direction. The injection hole is located at the bottom of the first recess. In the radial direction of the electrode terminals, the radial dimension of the injection hole is smaller than the radial dimension of the first recess. The first recess communicates with the interior of the casing through the injection hole. The first sealing member is at least partially disposed within the first recess and is used to seal the injection hole. The second sealing member is at least partially inserted into the first recess along the axial direction and is used to seal the first recess. The second sealing member presses against the first sealing member.

[0006] By using the above method, the second sealing element presses down on the first sealing element, which helps to improve the sealing effect of the first sealing element on the injection hole and reduce the risk of electrolyte leakage.

[0007] In some embodiments, the first sealing member includes a body portion disposed within a first recess and covering the injection hole, and the second sealing member surrounds the injection hole to press the body portion against the bottom of the first recess.

[0008] By means of the above method, the pressing action of the second sealing element forms an annular sealing area around the injection hole by the body, which helps to improve the sealing effect of the first sealing element on the injection hole.

[0009] In some embodiments, the body portion is an elastic body, and in the axial direction, the ratio between the amount of compression of the body portion under the pressure of the second sealing member and the thickness of the body portion in its natural state is greater than or equal to 0.1 and less than or equal to 0.5.

[0010] The above method helps the body maintain good elasticity and also helps the body form a good seal around the injection hole.

[0011] In some embodiments, the end face of the second sealing member facing the body portion is provided with a second recess and an annular pressing surface surrounding the second recess. The projection of the annular pressing surface along the axial direction at least partially surrounds the periphery of the injection hole, and the second sealing member presses the body portion through the annular pressing surface.

[0012] By using the above method, the pressure area of ​​the second sealing member on the main body can be reduced, which is conducive to the second sealing member effectively forming the above-mentioned annular sealing area with a relatively small pressure force.

[0013] In some embodiments, the axial projection of the annular pressing surface is entirely located around the injection hole.

[0014] The above method allows the second sealing element to effectively form the annular sealing area with relatively small holding force, while also mitigating unnecessary deformation of the body directly above the injection hole.

[0015] In some embodiments, in the axial direction, there is a height difference between the bottom of the second recess and the annular pressing surface, and the height difference is greater than the compression amount of the body portion when it is pressed by the second sealing member.

[0016] By means of the above method, when the second sealing member presses against the body part, a gap is formed between the bottom of the second recess and the body part, which can reduce the pressing force of the second sealing member on the body part.

[0017] In some embodiments, the difference between the height difference and the compression amount is greater than or equal to 0.05 mm.

[0018] In this way, a gap can be effectively formed between the bottom of the second recess and the body, and sufficient assembly redundancy can be provided.

[0019] In some embodiments, the radial dimension of the outer ring edge of the annular pressing surface is greater than or equal to the radial dimension of the outer peripheral surface of the body portion.

[0020] In this way, the annular pressing surface can act on the outer peripheral surface of the body, improving the sealing effect. At the same time, it provides radial expansion space for the body when it is pressed, which is conducive to the body being fully compressed.

[0021] In some embodiments, the difference between the radial dimension of the inner ring edge of the annular pressing surface and the radial dimension of the outer peripheral surface of the body portion is greater than or equal to 1 mm.

[0022] In this way, sufficient pressure area can be maintained between the second sealing element and the main body, thereby improving the sealing effect.

[0023] In some embodiments, a third recess is provided on the side of the body away from the injection hole, and the axial projection of the third recess falls into the injection hole.

[0024] By using the above method, the injection needle can be visually located at the third recess to determine the position of the injection hole, thereby improving the efficiency and accuracy of injection.

[0025] In some embodiments, a protrusion located around the third recess is provided on the side of the body portion away from the injection hole, and a fourth recess located at the bottom of the second recess is provided on the inner end face of the second sealing member facing the body portion, the fourth recess being used to avoid the protrusion.

[0026] By using the above method, during the material feeding stage of the first sealing component in the assembly process, the contact area between the first sealing component and other first sealing components on the side of the body away from the injection hole can be reduced, thereby reducing the situation where the first sealing components stick together, which is beneficial to improving assembly efficiency.

[0027] In some embodiments, the first sealing member further includes an insertion part, one end of which is connected to the body part and inserted into the injection hole.

[0028] In this way, the first sealing component can seal the injection hole, reducing the risk of electrolyte leakage from the injection hole inside the casing.

[0029] In some embodiments, the insertion part is an elastic body, and the outer peripheral surface of the insertion part is sealed to the wall of the injection hole by a tight fit.

[0030] By using the above method, the sealing effect of the insertion part on the injection hole can be improved while the assembly efficiency of the first sealing component can be increased.

[0031] In some embodiments, the difference between the radial dimension of the outer peripheral surface of the insertion part in its natural state and the radial dimension of the injection hole is greater than or equal to 0.2 mm and less than or equal to 0.8 mm.

[0032] By means of the above method, the insertion part can be compressed and exert sufficient elastic force on the wall of the injection hole, thereby forming a good seal between the insertion part and the wall of the injection hole, and also making it easier for the insertion part to be smoothly inserted into the injection hole during the assembly process.

[0033] In some embodiments, the first sealing member further includes a locking portion connected to the other end of the insertion portion away from the body portion. In the radial direction, the outer peripheral surface of the locking portion protrudes from the outer peripheral surface of the insertion portion and is used to abut against the side of the electrode terminal facing the inside of the housing when the insertion portion is inserted into the injection hole.

[0034] By using the above method, the locking part is used to prevent the first sealing member from moving in the direction away from the inside of the housing, so as to improve the stability of the connection between the first sealing member and the electrode terminal before the second sealing member presses the first sealing member.

[0035] In some embodiments, the insertion portion and the locking portion are elastic bodies, and in their natural state, the difference between the maximum radial dimension of the outer peripheral surface of the locking portion and the radial dimension of the outer peripheral surface of the insertion portion is greater than or equal to 0.1 mm.

[0036] The above method helps to improve the locking strength between the locking part and the electrode terminal, thereby effectively preventing the first sealing member from moving in the direction away from the inside of the housing.

[0037] In some embodiments, the thickness of the locking portion in the axial direction is greater than or equal to 0.5 mm.

[0038] The above method helps to improve the locking strength between the locking part and the electrode terminal, thereby effectively preventing the first sealing member from moving in the direction away from the inside of the shell.

[0039] In some embodiments, the locking part is provided with a guide surface at one end opposite to the insertion part, and the guide surface is used to guide the locking part through the injection hole.

[0040] The above method facilitates the smooth entry of the locking part into the injection hole during the assembly process, thereby improving assembly efficiency.

[0041] In some embodiments, on a reference section arranged along the axial direction, the angle of inclination of the guide surface relative to the axial direction is greater than or equal to 30° and less than or equal to 60°.

[0042] The above method facilitates the smooth entry of the locking part into the injection hole during assembly and improves the locking strength between the locking part and the electrode terminal.

[0043] In some embodiments, the battery cell further includes a current collector and an electrode assembly disposed inside the housing. The current collector is used to connect the tabs and electrode terminals of the electrode assembly, and the electrode terminals are welded to the current collector in the area corresponding to the bottom of the first recess.

[0044] The above method facilitates the electrical connection between the electrode terminals and the electrode assembly. Utilizing the thinner bottom of the first recess, it is welded to the current collector, allowing for easy electrical connection between the electrode terminals and the current collector from the side of the electrode terminals away from the current collector.

[0045] In some embodiments, the housing includes a housing and an end cap, one end of the housing having an opening, the end cap closing the opening, the housing including a side wall and a bottom wall, the side wall surrounding the outside of the electrode assembly, the bottom wall being disposed opposite to the opening, and the wall portion being either the end cap or the bottom wall.

[0046] The above methods can improve the assembly efficiency of individual battery cells.

[0047] Secondly, this application provides a battery, which includes the aforementioned battery cell.

[0048] Thirdly, this application provides an electrical device that includes the aforementioned battery.

[0049] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. [Attached Image Description]

[0050] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0051] Figure 1 This is a schematic diagram of the structure of a vehicle according to one or more embodiments;

[0052] Figure 2 This is an exploded structural diagram of a battery according to one or more embodiments;

[0053] Figure 3 This is a top view of a battery cell according to one or more embodiments;

[0054] Figure 4 for Figure 3 The diagram shows a cross-sectional structure of a single battery cell along the CC section.

[0055] Figure 5 for Figure 4 A schematic diagram of part A of the battery cell shown;

[0056] Figure 6 for Figure 5 A schematic diagram of part B of the shown battery cell;

[0057] Figure 7 for Figure 5 A schematic diagram of part D of the battery cell shown.

[0058] Figure 8 This is a schematic diagram showing the structural changes of the first sealing component during the assembly process.

[0059] Figure 9 This is a schematic diagram of the second sealing component.

[0060] The reference numerals in the detailed embodiments are as follows:

[0061] 1000a vehicles;

[0062] 100A battery; 200A controller; 300A motor;

[0063] 10a Enclosure; 11a First Section; 12a Second Section;

[0064] H1 Thickness of the main body in its natural state; H2 Height difference; H3 Compression amount; H4 Thickness of the locking part; D1 Outer ring edge of the annular pressing surface.

[0065] The radial dimension of the edge; the radial dimension of the outer peripheral surface of the body part; the radial dimension of the inner ring edge of the annular pressing surface; the radial dimension of the injection hole; the radial dimension of the outer peripheral surface of the insertion part in its natural state; the maximum radial dimension of the outer peripheral surface of the locking part; the radial dimension of the first recess; the angle α between the two line segments of the guide surface on the reference section set along the axial direction and the axial direction;

[0066] 1. Battery cell; 100. Casing; 101. Wall; 102. Outlet; 110. Housing; 111. Opening; 112. Side wall; 113. Bottom wall; 120. End cap;

[0067] 200 Electrode terminal; 210 First recess; 220 Injection hole; 300 First sealing element; 310 Body part; 311 Third recess; 312 Protrusion; 320 Insertion part; 330 Locking part; 331 Guide surface; 400 Second sealing element; 410 Second recess; 420 Annular pressing surface; 430 Fourth recess; 500 Electrode assembly; 501 Tab; 600 Collector plate.

Detailed Implementation Methods

[0068] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0069] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0070] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0071] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0072] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0073] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0074] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0075] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0076] With the development of battery technology, battery cells are being applied in more and more fields, gradually replacing traditional fossil fuels in the automotive power sector. Battery cells can store chemical energy and controllably convert it into electrical energy. In recyclable battery cells, the active materials can be reactivated through charging after discharge, allowing for continued use.

[0077] A single battery cell typically includes an electrode assembly, electrode terminals, a housing, and a sealing element. The housing houses the electrode assembly. The electrode assembly is electrically connected to the outside environment via the electrode terminals. The electrode terminals may have injection holes for injecting electrolyte into the housing. The sealing element is used to seal the injection holes. In existing battery cell structures, the sealing element's structure and function for sealing the injection holes are relatively simple, and its sealing effectiveness needs further improvement.

[0078] To improve the sealing effect on the injection port, a first sealing member and a second sealing member can be provided. The housing includes a wall portion with an outlet hole. An electrode terminal is inserted into the outlet hole along the axial direction of the electrode terminal. The electrode terminal has a first recess and an injection port connected axially. The injection port is located at the bottom of the first recess. In the radial direction of the electrode terminal, the radial dimension of the injection port is smaller than the radial dimension of the first recess. The first recess communicates with the interior of the housing through the injection port. The first sealing member is at least partially disposed in the first recess and is used to seal the injection port. The second sealing member is at least partially inserted axially into the first recess and is used to seal the first recess. The second sealing member presses against the first sealing member.

[0079] Based on the above considerations, this application provides a battery cell, a battery, and an electrical device. By providing a second sealing element to seal the first recess, the first sealing element can be protected, reducing the risk of the first sealing element's seal on the injection hole being damaged by the external environment. Furthermore, by providing the second sealing element to seal the first recess, the risk of electrolyte leakage can also be reduced. By providing the second sealing element to hold the first sealing element, a seal can be formed between the first and second sealing elements and between the electrode terminals, and it can also prevent the first sealing element from sliding out of the lead-out hole towards the second sealing element, thereby further reducing the risk of electrolyte leakage. Thus, the sealing effect on the injection hole can be improved.

[0080] The battery cell, battery, and electrical device disclosed in this application can be used in electrical devices that use batteries as a power source or in various energy storage systems that use batteries as energy storage elements. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc., while spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0081] For ease of explanation, the following embodiments will be described using a vehicle 1000a as an example of an electrical device according to an embodiment of this application.

[0082] Please refer to Figure 1 Vehicle 1000a can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery 100a is internally installed in vehicle 1000a, and the battery 100a can be located at the bottom, front, or rear of vehicle 1000a. The battery 100a can be used to power vehicle 1000a; for example, the battery 100a can serve as the operating power source for vehicle 1000a. Vehicle 1000a may also include a controller 200a and a motor 300a. The controller 200a is used to control the battery 100a to supply power to the motor 300a, for example, to meet the power needs of vehicle 1000a during starting, navigation, and driving.

[0083] In some embodiments of this application, the battery 100a can not only serve as the operating power source for the vehicle 1000a, but also as the driving power source for the vehicle 1000a, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000a.

[0084] In some embodiments, battery 100a may be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0085] The battery 100a mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells 1 to provide higher voltage and capacity.

[0086] In this embodiment, each battery cell 1 can be a secondary battery, which refers to a battery cell that can be recharged after discharge to activate the active materials and continue to be used. Each battery cell 1 can also be a primary battery.

[0087] Battery cell 1 includes, but is not limited to, lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc. Battery cell 1 may be cylindrical, flat, cuboid, or other shapes.

[0088] In some embodiments, the battery 100a can be a battery module. When there are multiple battery cells 1, the multiple battery cells 1 are arranged and fixed to form a battery module.

[0089] In some embodiments, please refer to Figure 2 The battery 100a can be a battery pack, which includes a housing 10a and a battery cell 1, with the battery cell 1 or battery module housed in the housing 10a.

[0090] In some embodiments, the housing 10a may be part of the chassis structure of the vehicle 1000a. For example, a portion of the housing 10a may be at least a portion of the floor of the vehicle 1000a, or a portion of the housing 10a may be at least a portion of the crossbeams and longitudinal beams of the vehicle 1000a.

[0091] Please refer to Figure 2 The battery 100a includes a housing 10a and a battery cell 1, with the battery cell 1 housed within the housing 10a. The housing 10a provides a space for the battery cell 1 and can have various structures. In some embodiments, the housing 10a may include a first portion 11a and a second portion 12a, which overlap each other, together defining a space for accommodating the battery cell 1. The second portion 12a may be a hollow structure with one open end, and the first portion 11a may be a plate-like structure, covering the open side of the second portion 12a so that the first portion 11a and the second portion 12a together define the space. Alternatively, both the first portion 11a and the second portion 12a may be hollow structures with one open side, with the open side of the first portion 11a covering the open side of the second portion 12a. Of course, the housing 10a formed by the first portion 11a and the second portion 12a can have various shapes, such as a cylinder or a cuboid.

[0092] In battery 100a, there can be multiple battery cells 1, which can be connected in series, parallel, or in a mixed manner. A mixed connection means that multiple battery cells 1 are connected in both series and parallel configurations. Multiple battery cells 1 can be directly connected in series, parallel, or in a mixed manner, and then the entire assembly of the multiple battery cells 1 is housed within the casing 10a. Alternatively, battery 100a can also consist of multiple battery cells 1 first connected in series, parallel, or in a mixed manner to form a battery module, and then multiple battery modules are connected in series, parallel, or in a mixed manner to form a whole, which is also housed within the casing 10a. Battery 100a may also include other structures; for example, it may include a busbar component for electrical connection between the multiple battery cells 1.

[0093] Each battery cell 1 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited to these. The battery cell 1 can be cylindrical, flat, cuboid, or other shapes.

[0094] Please refer to Figure 3 and Figure 4 In this context, "battery cell 1" refers to the smallest unit that makes up the battery. In this embodiment, a cylindrical battery cell 1 is used as an example for description. Figure 4 As shown, the battery cell 1 includes a housing 100, an electrode assembly 500, and other functional components.

[0095] In some embodiments, the housing 100 is used to encapsulate the electrode assembly 500 and components such as the electrolyte. The housing 100 can be a steel housing, an aluminum housing, a plastic housing (such as a polypropylene housing), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film, etc.

[0096] The housing 100 may include an end cap 120 and a housing 110. The end cap 120 is a component that closes onto the opening 111 of the housing 110 to isolate the internal environment of the battery cell 1 from the external environment. Not limited to this, the shape of the end cap 120 may be adapted to the shape of the housing 110 to fit it. Optionally, the end cap 120 may be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 120 is less prone to deformation under pressure and impact, allowing the battery cell 1 to have higher structural strength and improved safety performance. Functional components such as electrode terminals 200 may be provided on the end cap 120. The electrode terminals 200 can be used for electrical connection with the electrode assembly 500 for outputting or inputting electrical energy from the battery cell 1. In some embodiments, the end cap 120 may also be provided with a pressure relief mechanism for releasing internal pressure when the internal pressure or temperature of the battery cell 1 reaches a threshold. The end cap 120 can be made of various materials, including but not limited to copper, iron, aluminum, stainless steel, aluminum alloy, and plastic. In some embodiments, an insulating element may be provided on the inner side of the end cap 120. The insulating element can be used to isolate the electrical connection components within the housing 110 from the end cap 120 to reduce the risk of short circuits. For example, the insulating element can be plastic, rubber, etc.

[0097] The housing 110 is a component used to cooperate with the end cap 120 to form the internal environment of the battery cell 1. This internal environment can accommodate the electrode assembly 500, electrolyte, and other components. The housing 110 and the end cap 120 can be independent components. An opening 111 can be provided on the housing 110, and the end cap 120 can close the opening 111 to form the internal environment of the battery cell 1. Alternatively, the end cap 120 and the housing 110 can be integrated. Specifically, the end cap 120 and the housing 110 can form a common connecting surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 110, the end cap 120 closes the housing 110. The housing 110 can have various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 110 can be determined according to the specific shape and size of the electrode assembly 500. The housing 110 can be made of various materials, including but not limited to copper, iron, aluminum, stainless steel, aluminum alloy, and plastic.

[0098] Electrode assembly 500 is a component in the battery cell 1 where an electrochemical reaction occurs. The housing 110 may contain one or more electrode assemblies 500.

[0099] In some embodiments, the electrode assembly 500 includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of a single battery cell, active ions (e.g., lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, disposed between the positive and negative electrodes, serves to prevent short circuits between the positive and negative electrodes while allowing active ions to pass through.

[0100] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0101] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the two opposite surfaces of the positive current collector.

[0102] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as a metal foil, it can be aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0103] As an example, the positive electrode active material may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxide may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.85 Co 0.15 Al 0.05 At least one of O2 and its modified compounds.

[0104] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0105] As an example, the negative electrode current collector can be a metal foil, a foamed metal, or a composite current collector. For example, as a metal foil, it can be silver-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, carbon electrodes, carbon, nickel, or titanium, etc. Foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0106] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0107] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0108] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cells. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as battery negative electrode active materials may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0109] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0110] In some embodiments, the electrode assembly 500 further includes an isolator disposed between the positive and negative electrodes.

[0111] In some embodiments, the separator is a separator membrane. This application does not impose any particular limitation on the type of separator membrane; any known porous separator membrane with good chemical and mechanical stability can be selected.

[0112] As an example, the main material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramic. The separator can be a single-layer film or a multi-layer composite film, without particular limitation. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without particular limitation. The separator can be a separate component located between the positive and negative electrodes, or it can be attached to the surfaces of the positive and negative electrodes.

[0113] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrodes, serving both to transport ions and to isolate the positive and negative electrodes.

[0114] In some embodiments, the battery cell also includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. This application does not impose specific limitations on the type of electrolyte; it can be selected according to requirements. The electrolyte can be liquid, gel, or solid.

[0115] Liquid electrolytes include electrolyte salts and solvents.

[0116] In some embodiments, the electrolyte salt may be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0117] In some embodiments, the solvent may be selected from at least one of ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent may also be an ether solvent. Ether solvents may include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0118] Among them, the gel electrolyte includes a polymer as the electrolyte backbone network, combined with an ionic liquid - lithium salt.

[0119] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0120] As an example, polymer solid electrolytes can be polyether (polyoxyethylene), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids-lithium salts, cellulose, etc.

[0121] As an example, inorganic solid electrolytes can be one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium germanium phosphorus sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0122] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0123] In some embodiments, the electrode assembly 500 is a wound structure. The positive electrode and the negative electrode are wound into a wound structure.

[0124] In some embodiments, the electrode assembly 500 is provided with tabs 501, which can conduct current from the electrode assembly 500. The tabs include a positive tab and a negative tab. The positive and negative tabs can be located together at one end of the main body or at opposite ends of the main body. During the charging and discharging process of the battery 100a, the positive and negative active materials react with the electrolyte, and the tabs 501 connect to the electrode terminals to form a current loop.

[0125] According to some embodiments of this application, such as Figures 4 to 6As shown in the embodiment of this application, the battery cell 1 includes a housing 100, electrode terminals 200, a first sealing member 300, and a second sealing member 400. The housing 100 includes a wall portion 101 with a lead-out hole 102. The electrode terminals 200 are inserted into the lead-out hole 102 along their axial direction. The electrode terminals 200 have a first recess 210 and an injection hole 220 connected axially. The injection hole 220 is located at the bottom of the first recess 210. In the radial direction of the electrode terminals 200, the radial dimension D4 of the injection hole 220 is smaller than the radial dimension D7 of the first recess 210. The first recess 210 communicates with the interior of the housing 100 via the injection hole 220. The first sealing member 300 is at least partially disposed within the first recess 210 and is used to seal the injection hole 220. The second sealing member 400 is at least partially inserted axially into the first recess 210 and is used to seal the first recess 210. The second sealing member 400 presses against the first sealing member 300.

[0126] The axial direction of electrode terminal 200 refers to the distance between the end of electrode terminal 200 facing the interior of housing 100 and the end facing away from the interior of housing 100, while the radial direction of electrode terminal 200 refers to the direction perpendicular to the axial direction of electrode terminal 200. Unless otherwise specified, the axial and radial directions mentioned below refer to the axial and radial directions of electrode terminal 200.

[0127] The electrode terminal 200 can be installed in the housing 100 by being inserted axially into the lead-out hole 102. Specifically, one end of the electrode terminal 200 is disposed facing the inside of the housing 100 and can be used to electrically connect to the electrode assembly 500 disposed inside the housing 100. The other end of the electrode terminal 200 is disposed facing the outside of the housing 100 and can be connected to the outside, thereby enabling the charging and discharging of the electrode assembly 500.

[0128] During the assembly of the battery cell 1, the electrolyte is injected sequentially through the first recess 210 and the injection hole 220 before entering the housing 100. By setting the radial dimension D7 of the first recess 210 to be larger than the radial dimension D4 of the injection hole 220, it is convenient for external devices to inject electrolyte into the housing 100 through the first recess 210. By setting the radial dimension D4 of the injection hole 220 to be smaller than the radial dimension D7 of the first recess 210, it is convenient to seal the injection hole 220 with the first sealing member 300 after the electrolyte injection is completed, thereby reducing the risk of electrolyte leakage.

[0129] By providing a second sealing element 400 to seal the first recess 210, the first sealing element 300 can be protected, reducing the risk that the sealing of the injection hole 220 by the first sealing element 300 will be damaged by the external environment. Furthermore, by providing the second sealing element 400 to seal the first recess 210, the risk of electrolyte leakage can also be reduced.

[0130] By setting the second sealing member 400 to press the first sealing member 300, a seal can be formed between the first sealing member 300, the second sealing member 400, and the electrode terminal 200. This also prevents the first sealing member 300 from sliding out of the outlet hole 102 in the direction of the second sealing member 400, thereby further reducing the risk of electrolyte leakage.

[0131] Optionally, the two ends of the injection hole 220 along the axial direction can be connected to the first recess 210 and the interior of the outer casing 100, respectively.

[0132] According to some embodiments of this application, optionally, such as Figure 5 and Figure 7 As shown, the first sealing member 300 includes a body portion 310, which is disposed in the first recess 210 and covers the injection hole 220. The second sealing member 400 surrounds the injection hole 220 and presses the body portion 310 against the bottom of the first recess 210.

[0133] like Figures 5 to 7 As shown, the radial dimension D2 of the body portion 310 can be larger than the radial dimension D4 of the injection hole 220. When the body portion 310 is projected axially toward the injection hole 220, the projection of the body portion 310 can partially fall on the periphery of the injection hole 220, so that the body portion 310 will not be pressed into the interior of the outer casing 100 by the second sealing member 400 through the injection hole 220.

[0134] The pressing action of the second sealing member 400 allows the body portion 310 to form an annular sealing area around the injection hole 220, which improves the sealing effect of the first sealing member 300 on the injection hole 220. Specifically, under the pressing action of the second sealing member 400, the body portion 310 abuts against the outer periphery of the second sealing member 400 and the injection hole 220, thus forming a seal between the body portion 310 and both the second sealing member 400 and the outer periphery of the injection hole 220, effectively mitigating electrolyte leakage.

[0135] According to some embodiments of this application, optionally, such as Figure 7 and Figure 8 As shown, the body portion 310 is an elastic body. In the axial direction, the ratio between the compression amount H3 of the body portion 310 under the pressure of the second sealing member 400 and the thickness H1 of the body portion 310 in its natural state is greater than or equal to 0.1 and less than or equal to 0.5. For example, H3 / H1 can be set to 0.15, 0.2, 0.3, 0.4, etc.

[0136] After being compressed within its elastic limit, the body portion 310 tends to elastically recover, thereby enabling it to elastically seal against the periphery of the first sealing member 300 and the injection hole 220. The greater the compression amount H3 of the body portion 310 within its elastic limit, the greater the elasticity of the body portion 310, and the better the sealing effect between the body portion 310 and the periphery of the first sealing member 300 and the injection hole 220. In the axial direction, by setting the ratio between the compression amount H3 of the body portion 310 under the pressure of the second sealing member 400 and the thickness H1 of the body portion 310 in its natural state to be greater than or equal to 0.1, it is beneficial for the body portion 310 to form a good seal with the periphery of the second sealing member 400 and the injection hole 220.

[0137] If the body portion 310 is compressed beyond its elastic limit, it will damage the elasticity of the body portion 310 and adversely affect the sealing effect. In the axial direction, by setting the ratio between the compression amount H3 of the body portion 310 under the pressure of the second sealing member 400 and the thickness H1 of the body portion 310 in its natural state to be less than or equal to 0.5, the risk of the compression amount H3 of the body portion 310 exceeding the elastic limit can be reduced, which helps the body portion 310 maintain good elasticity and thus achieve a good sealing effect.

[0138] The second sealing member 400 exerts a pressing force on the first sealing member 300, and correspondingly, the first sealing member 300 exerts an elastic force on the second sealing member 400, causing the second sealing member 400 to tend to move away from the electrode terminal 200. The second sealing member 400 can form a connection with the electrode terminal 200 to maintain the pressing force on the first sealing member 300. When the compression amount H3 of the body portion 310 is greater than 0.5, the elastic force of the body portion 310 can adversely affect the connection between the second sealing member 400 and the electrode terminal 200.

[0139] Furthermore, the body part 310 is made of an elastic polymer material, such as silicone or rubber.

[0140] According to some embodiments of this application, optionally, such as Figure 5 and Figure 9 As shown, the second sealing member 400 has a second recess 410 and an annular pressing surface 420 surrounding the second recess 410 on its end face facing the body portion 310. The projection of the annular pressing surface 420 along the axial direction at least partially surrounds the periphery of the injection hole 220. The second sealing member 400 presses the body portion 310 through the annular pressing surface 420.

[0141] By providing the second recess 410, an annular pressing surface 420 can be formed on the end face of the second sealing member 400 facing the body portion 310. By forming the annular pressing surface 420, the pressing area of ​​the second sealing member 400 on the body portion 310 can be reduced, thereby reducing the pressing force of the second sealing member 400 on the body portion 310, which is beneficial for the second sealing member 400 to effectively form the aforementioned annular sealing area with a relatively small pressing force.

[0142] By setting the annular pressing surface 420 so that its projection along the axial direction is at least partially located around the injection hole 220, the annular pressing surface 420 can effectively press against the body portion 310.

[0143] According to some embodiments of this application, optionally, such as Figure 5 As shown, the projection of the annular pressing surface 420 along the axial direction is located entirely around the injection hole 220.

[0144] The radial dimension D3 of the inner ring edge of the annular pressing surface 420 can be larger than the radial dimension D4 of the injection hole 220. This reduces the radial width of the annular pressing surface 420, thereby reducing the pressing area of ​​the second sealing member 400 on the body portion 310. This reduces the pressing force of the second sealing member 400 on the body portion 310, which is beneficial for the second sealing member 400 to effectively form the aforementioned annular sealing area with a relatively small pressing force, while also mitigating unnecessary deformation of the body portion 310 directly above the injection hole 220.

[0145] According to some embodiments of this application, optionally, such as Figure 7 As shown, in the axial direction, the bottom of the second recess 410 and the annular pressing surface 420 have a height difference H2, which is greater than the compression amount H3 of the body 310 when it is pressed by the second sealing member 400.

[0146] By setting the height difference H2 to be greater than the compression amount H3, when the first sealing member 300 presses against the body part 310, a gap is formed between the bottom of the second recess 410 and the body part 310, which can reduce the pressing force of the second sealing member 400 on the body part 310 and provide assembly redundancy.

[0147] According to some embodiments of this application, optionally, such as Figure 7 As shown, the difference between the height difference H2 and the compression amount H3 is greater than or equal to 0.05 mm. For example, H2-H3 can be set to 0.1 mm, 0.2 mm, 0.3 mm, 0.5 mm, 0.8 mm, 1 mm, etc.

[0148] By setting the difference between the height difference H2 and the compression amount H3 to be greater than or equal to 0.05 mm, a gap can be effectively formed between the bottom of the second recess 410 and the body portion 310, and sufficient assembly redundancy can be provided.

[0149] According to some embodiments of this application, optionally, such as Figure 5 As shown, in the radial direction, the radial dimension D1 of the outer ring edge of the annular pressing surface 420 is greater than or equal to the radial dimension D2 of the outer peripheral surface of the body part 310.

[0150] In the radial direction, by setting the radial dimension D1 of the outer ring edge of the annular pressing surface 420 to be greater than or equal to the radial dimension D2 of the outer peripheral surface of the body part 310, the annular pressing surface 420 can act on the outer peripheral surface of the body part 310, thereby improving the sealing effect. At the same time, it provides radial expansion space for the body part 310 when it is pressed, which is beneficial for the body part 310 to be fully compressed.

[0151] According to some embodiments of this application, optionally, such as Figure 5 As shown, in the radial direction, the difference between the radial dimension D3 of the inner ring edge of the annular pressing surface 420 and the radial dimension D2 of the outer peripheral surface of the body part 310 is greater than or equal to 1 mm. For example, D2-D3 can be set to 1.5 mm, 2 mm, 3 mm, etc.

[0152] In the radial direction, by setting the difference between the radial dimension D3 of the inner ring edge of the annular pressing surface 420 and the radial dimension D2 of the outer peripheral surface of the body part 310 to be greater than or equal to 1 mm, sufficient pressing area can be maintained between the second sealing member 400 and the body part 310, thereby improving the sealing effect between the body part 310, the second sealing member 400, and the electrode terminal 200.

[0153] According to some embodiments of this application, optionally, such as Figure 6 As shown, a third recess 311 is provided on the side of the main body 310 away from the injection hole 220, and the projection of the third recess 311 along the axial direction falls inside the injection hole 220.

[0154] During the assembly of battery cell 1, after the first sealing member 300 seals the injection hole 220, electrolyte can be injected into the interior of the outer casing 100 through the injection needle penetrating the first sealing member 300. By providing a third recess 311 with its axial projection falling within the injection hole 220, the injection needle can visually locate the third recess 311 to determine the position of the injection hole 220, thereby improving the efficiency and accuracy of electrolyte injection.

[0155] During injection, the injection needle can first visually locate the third recess 311, and then penetrate the first sealing member 300 axially from the bottom of the third recess 311, so that the injection needle can inject electrolyte into the interior of the outer casing 100 through the injection hole 220. In addition, the third recess 311 reduces the penetration distance of the injection needle, making it easier for the injection needle to penetrate the first sealing member 300.

[0156] According to some embodiments of this application, optionally, such as Figure 5 and Figure 6 As shown, the main body 310 is provided with a protrusion 312 located on the periphery of the third recess 311 on the side opposite to the injection hole 220. The second sealing member 400 is also provided with a fourth recess 430 located at the bottom of the second recess 410 on the inner end face of the main body 310. The fourth recess 430 is used to avoid the protrusion 312.

[0157] Multiple first sealing components 300 are prone to sticking together after contact, and the larger the contact area between each first sealing component 300, the more likely sticking will occur. By providing the protrusion 312, during the feeding stage of the first sealing components 300 in the assembly process, the contact area between each first sealing component 300 and other first sealing components 300 on the side of the body part 310 away from the injection hole 220 can be reduced, thereby reducing the possibility of sticking between multiple first sealing components 300, which is beneficial to improving assembly efficiency and reducing defects caused by sticking of the first sealing components 300 during the assembly process.

[0158] According to some embodiments of this application, optionally, such as Figure 6 As shown, the first sealing member 300 also includes an insertion part 320, one end of which is connected to the main body part 310 and inserted into the injection hole 220.

[0159] By inserting the insertion part 320 into the injection hole 220, the first sealing member 300 can seal the injection hole 220, reducing the risk of electrolyte leakage from the injection hole 220 inside the housing 100.

[0160] According to some embodiments of this application, optionally, such as Figure 6 As shown, the insertion part 320 is an elastic body, and the outer peripheral surface of the insertion part 320 and the wall of the injection hole 220 are sealed to each other by a tight fit.

[0161] The radial dimension of the insertion part 320 can be larger than the radial dimension D4 of the injection hole 220. When the insertion part 320 is inserted into the injection hole 220, it will be compressed and tend to elastically recover, thereby being able to abut against the hole wall of the injection hole 220 through elastic force, and forming a seal between the insertion part 320 and the hole wall of the injection hole 220 in a tight fit manner.

[0162] This configuration can improve the sealing effect of the insertion part 320 on the injection hole 220 while improving the assembly efficiency of the first sealing part 300.

[0163] According to some embodiments of this application, optionally, such as Figure 6As shown, in the radial direction, the difference between the radial dimension D5 of the outer peripheral surface of the insertion part 320 in its natural state and the radial dimension D4 of the injection hole 220 is greater than or equal to 0.2 mm and less than or equal to 0.8 mm. For example, D5-D4 can be set to 0.25 mm, 0.3 mm, 0.5 mm, 0.6 mm, etc.

[0164] In the radial direction, by setting the difference between the radial dimension D5 of the outer peripheral surface of the insertion part 320 in its natural state and the radial dimension D4 of the injection hole 220 to be greater than or equal to 0.2 mm, the insertion part 320 can be compressed and abut against the hole wall of the injection hole 220, and apply sufficient elastic force to the hole wall of the injection hole 220, thereby forming a good seal between the insertion part 320 and the hole wall of the injection hole 220.

[0165] In the radial direction, by setting the difference between the radial dimension D5 of the outer peripheral surface of the insertion part 320 in its natural state and the radial dimension D4 of the injection hole 220 to be less than or equal to 0.8 mm, the insertion part 320 can be easily compressed and deformed to be inserted into the injection hole 220, which is beneficial for the insertion part 320 to be smoothly inserted into the injection hole 220 during the assembly process and improves the assembly efficiency.

[0166] According to some embodiments of this application, optionally, such as Figure 5 and Figure 6 As shown, the first sealing member 300 also includes a locking part 330, which is connected to the other end of the insertion part 320 away from the body part 310. In the radial direction, the outer peripheral surface of the locking part 330 protrudes from the outer peripheral surface of the insertion part 320 and is used to abut against the side of the electrode terminal 200 facing the inside of the housing 100 when the insertion part 320 is inserted into the injection hole 220.

[0167] The maximum radial dimension D6 of the outer peripheral surface of the locking part 330 can be greater than the radial dimension D5 of the outer peripheral surface of the insertion part 320. By providing the locking part 330, the first sealing member 300 can be prevented from moving in a direction away from the interior of the housing 100, so as to improve the stability of the connection between the first sealing member 300 and the electrode terminal 200 before the second sealing member 400 presses the first sealing member 300.

[0168] According to some embodiments of this application, optionally, such as Figure 6 As shown, the insertion part 320 and the locking part 330 are elastic bodies. In their natural state, the difference between the maximum radial dimension D6 of the outer peripheral surface of the locking part 330 and the radial dimension D5 of the outer peripheral surface of the insertion part 320 is greater than or equal to 0.1 mm. For example, D6-D5 can be set to 0.15 mm, 0.2 mm, 0.3 mm, 0.5 mm, etc.

[0169] By setting the difference between the maximum radial dimension D6 of the outer peripheral surface of the locking part 330 and the radial dimension D5 of the outer peripheral surface of the insertion part 320 to be greater than or equal to 0.1 mm, the radial dimension of the locking part 330 after being compressed to a certain extent can still be greater than the radial dimension D4 of the injection hole 220. This is beneficial to improve the locking strength between the locking part 330 and the electrode terminal 200, thereby effectively preventing the first sealing member 300 from moving in the direction away from the interior of the outer casing 100.

[0170] According to some embodiments of this application, optionally, such as Figure 6 As shown, in the axial direction, the thickness H4 of the locking part 330 is greater than or equal to 0.5 mm. For example, H4 can be set to 0.6 mm, 0.7 mm, 0.8 mm, 1 mm, 2 mm, etc.

[0171] In the axial direction, the less the thickness H4 of the locking part 330, the easier it is for the locking part 330 to deform under force to a radial dimension smaller than the radial dimension D4 of the injection hole 220. In the axial direction, by setting the thickness H4 of the locking part 330 to be greater than or equal to 0.5 mm, the radial dimension of the locking part 330 after compression can still be greater than the radial dimension D4 of the injection hole 220, which helps to improve the locking strength between the locking part 330 and the electrode terminal 200, thereby effectively preventing the first sealing member 300 from moving in the direction away from the interior of the housing 100.

[0172] According to some embodiments of this application, optionally, such as Figure 6 As shown, the locking part 330 has a guide surface 331 at one end opposite to the insertion part 320. The guide surface 331 is used to guide the locking part 330 through the injection hole 220.

[0173] By setting the guide surface 331, the locking part 330 can smoothly enter the injection hole 220 during the assembly process, thereby improving the assembly efficiency.

[0174] Furthermore, the guide surface 331 is part of a conical surface. The radial dimension of the end of the guide surface 331 that first enters the injection hole 220 is smaller than the radial dimension D4 of the injection hole 220, which facilitates the smooth entry of the locking part 330 into the injection hole 220 during assembly.

[0175] According to some embodiments of this application, optionally, such as Figure 6 As shown, on the reference section set along the axial direction, the tilt angle α of the guide surface 331 relative to the axial direction is greater than or equal to 30° and less than or equal to 60°. For example, the guide surface 331 can be set to 35°, 40°, 45°, 50°, etc. relative to the axial direction.

[0176] On a reference section arranged along the axial direction, the guide surface 331 can be represented by two line segments. The angle α between the two line segments of the guide surface 331 on the reference section arranged along the axial direction and the axial direction is greater than or equal to 30° and less than or equal to 60°. For example, the reference section can be... Figure 3 The CC section shown.

[0177] By setting the guide surface 331 at an angle greater than or equal to 30° relative to the axial direction, the two ends of the guide surface 331 can have a sufficient size difference, which is beneficial for the locking part 330 to smoothly enter the injection hole 220 during the assembly process.

[0178] By setting the guide surface 331 to be less than or equal to 60° relative to the axial direction, the size difference between the two ends of the guide surface 331 can be kept within an acceptable range. This is beneficial for the guide surface 331 to support the locking part 330, reduce the degree of deformation of the locking part 330 under stress, and thus effectively prevent the first sealing member 300 from moving in the direction away from the interior of the outer shell 100.

[0179] According to some embodiments of this application, optionally, such as Figure 4 and Figure 5 As shown, the battery cell 1 also includes a current collector 600 and an electrode assembly 500 disposed inside the housing 100. The current collector 600 is used to connect the tabs 501 and electrode terminals 200 of the electrode assembly 500. The electrode terminals 200 are welded to the current collector 600 in the area corresponding to the bottom of the first recess 210.

[0180] The current collector 600 can be disposed between the electrode terminal 200 and the electrode assembly 500, and serves to form a current path between the electrode terminal 200 and the electrode assembly 500. By providing the current collector 600, it is convenient to realize the electrical connection between the electrode terminal 200 and the electrode assembly 500. Taking advantage of the thin bottom thickness of the first recess 210, it is welded to the current collector 600, which facilitates the electrical connection between the electrode terminal 200 and the current collector 600 from the side of the electrode terminal 200 away from the current collector 600.

[0181] According to some embodiments of this application, optionally, such as Figure 4 and Figure 5 As shown, the housing 100 includes a housing 110 and an end cap 120. One end of the housing 110 has an opening 111, and the end cap 120 covers the opening 111. The housing 110 includes a side wall 112 and a bottom wall 113. The side wall 112 surrounds the outside of the electrode assembly 500, and the bottom wall 113 is disposed opposite to the opening 111. The wall portion 101 is either the end cap 120 or the bottom wall 113.

[0182] In the above embodiment, the wall portion 101 is a bottom wall 113. In other embodiments, the wall portion 101 may also be an end cap 120.

[0183] Since the end cap 120 or bottom wall 113 is flatter than the side wall 112, the assembly efficiency of the battery cell 1 can be improved by setting the electrode terminal 200, the first sealing member 300 and the second sealing member 400 on the end cap 120 or bottom wall 113.

[0184] According to some embodiments of this application, optionally, such as Figures 3 to 9As shown, the battery cell 1 includes a housing 100, electrode terminals 200, a first sealing member 300, and a second sealing member 400. The housing 100 includes a wall portion 101 with an outlet hole 102. The electrode terminals 200 are inserted into the outlet hole 102 along the axial direction of the electrode terminals 200. The electrode terminals 200 have a first recess 210 and an injection hole 220 connected along the axial direction. The injection hole 220 is located at the bottom of the first recess 210. In the radial direction of the electrode terminals 200, the radial dimension D4 of the injection hole 220 is smaller than the radial dimension D7 of the first recess 210. The first recess 210 communicates with the interior of the housing 100 through the injection hole 220. The first sealing member 300 is at least partially disposed within the first recess 210 and is used to seal the injection hole 220. The second sealing member 400 is at least partially inserted axially into the first recess 210 and is used to seal the first recess 210. The second sealing member 400 presses against the first sealing member 300. The first sealing member 300 includes a body portion 310, which is disposed within the first recess 210 and covers the injection hole 220. The second sealing member 400 surrounds the injection hole 220 and presses the body portion 310 against the bottom of the first recess 210. The body portion 310 is an elastic body. In the axial direction, the ratio between the compression amount H3 of the body portion 310 under the pressure of the second sealing member 400 and the thickness H1 of the body portion 310 in its natural state is greater than or equal to 0.1 and less than or equal to 0.5. The second sealing member 400 has a second recess 410 and an annular pressing surface 420 surrounding the second recess 410 on its end face facing the main body 310. The axial projection of the annular pressing surface 420 at least partially surrounds the periphery of the injection hole 220, and the second sealing member 400 presses the main body 310 through the annular pressing surface 420. The axial projection of the annular pressing surface 420 is entirely located around the periphery of the injection hole 220. In the axial direction, there is a height difference H2 between the bottom of the second recess 410 and the annular pressing surface 420, which is greater than the compression amount H3 of the main body 310 when it is pressed by the second sealing member 400. The difference between the height difference H2 and the compression amount H3 is greater than or equal to 0.05 mm. In the radial direction, the radial dimension D1 of the outer ring edge of the annular pressing surface 420 is greater than or equal to the radial dimension D2 of the outer peripheral surface of the main body 310. In the radial direction, the difference between the radial dimension D3 of the inner ring edge of the annular pressing surface 420 and the radial dimension D2 of the outer peripheral surface of the body portion 310 is greater than or equal to 1 mm. A third recess 311 is provided on the side of the body portion 310 away from the injection hole 220, and the axial projection of the third recess 311 falls within the injection hole 220. A protrusion 312 is provided on the side of the body portion 310 away from the injection hole 220, located around the third recess 311. The second sealing member 400 also has a fourth recess 430 located at the bottom of the second recess 410 on the inner end face of the body portion 310, which is used to avoid the protrusion 312.The first sealing member 300 further includes an insertion portion 320, one end of which is connected to the body portion 310 and inserted into the injection hole 220. The insertion portion 320 is an elastic body, and its outer peripheral surface and the wall of the injection hole 220 are sealed to each other by a tight fit. In the radial direction, the difference between the radial dimension D5 of the outer peripheral surface of the insertion portion 320 in its natural state and the radial dimension D4 of the injection hole 220 is greater than or equal to 0.2 mm and less than or equal to 0.8 mm. The first sealing member 300 also includes a locking portion 330, which is connected to the other end of the insertion portion 320 away from the body portion 310. In the radial direction, the outer peripheral surface of the locking portion 330 protrudes from the outer peripheral surface of the insertion portion 320 and is used to abut against the side of the electrode terminal 200 facing the inside of the housing 100 when the insertion portion 320 is inserted into the injection hole 220. The insertion portion 320 and the locking portion 330 are elastic bodies. In their natural state, the difference between the maximum radial dimension D6 of the outer peripheral surface of the locking portion 330 and the radial dimension D5 of the outer peripheral surface of the insertion portion 320 is greater than or equal to 0.1 mm. In the axial direction, the thickness H4 of the locking portion 330 is greater than or equal to 0.5 mm. A guide surface 331 is provided at the end of the locking portion 330 facing away from the insertion portion 320. The guide surface 331 is used to guide the locking portion 330 through the injection hole 220. In a reference section arranged along the axial direction, the inclination angle of the guide surface 331 relative to the axial direction is greater than or equal to 30° and less than or equal to 60°. The battery cell 1 also includes a current collector 600 and an electrode assembly 500 disposed inside the housing 100. The current collector 600 is used to connect the tabs 501 and electrode terminals 200 of the electrode assembly 500. The electrode terminals 200 are welded to the current collector 600 in the area corresponding to the bottom of the first recess 210. The housing 100 includes a housing 110 and an end cap 120. One end of the housing 110 has an opening 111, and the end cap 120 covers the opening 111. The housing 110 includes a side wall 112 and a bottom wall 113. The side wall 112 surrounds the outside of the electrode assembly 500, and the bottom wall 113 is disposed opposite to the opening 111. The wall portion 101 is either the end cap 120 or the bottom wall 113.

[0185] According to some embodiments of this application, such as Figure 2 As shown, battery 100a includes the aforementioned battery cell 1. This configuration improves the stability and reliability of battery cell 1 during operation by enhancing the sealing effect on the injection hole 220, thereby improving the stability and reliability of battery 100a during operation.

[0186] According to some embodiments of this application, such as Figure 1 As shown, the electrical device includes the aforementioned battery 100a. This configuration improves the stability and reliability of the battery 100a during operation by enhancing the stability and reliability of the individual battery cells 1, thereby improving the stability and reliability of the electrical device itself.

[0187] In summary, the embodiments of this application can form a seal between the first sealing member 300 and the second sealing member 400, as well as between the first sealing member 300, the second sealing member 400, and the electrode terminal 200 by setting the second sealing member 400 to hold the first sealing member 300. This can also prevent the first sealing member 300 from sliding out of the outlet hole 102 in the direction of the second sealing member 400, thereby improving the sealing effect on the injection hole 220 and reducing the risk of electrolyte leakage.

[0188] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized by, The battery cell includes: An outer casing, the outer casing including a wall portion having an outlet hole; An electrode terminal is inserted into the lead-out hole along the axial direction of the electrode terminal. The electrode terminal has a first recess and an injection hole connected along the axial direction. The injection hole is located at the bottom of the first recess. In the radial direction of the electrode terminal, the radial dimension of the injection hole is smaller than the radial dimension of the first recess. The first recess communicates with the interior of the outer casing through the injection hole. The first sealing element is at least partially disposed within the first recess and is used to seal the injection hole; A second sealing member is inserted at least partially along the axial direction into the first recess and is used to seal the first recess, wherein the second sealing member presses against the first sealing member.

2. The battery cell of claim 1, wherein, The first sealing member includes a body portion disposed within the first recess and covering the injection hole. The second sealing member surrounds the injection hole and presses the body portion against the bottom of the first recess.

3. The battery cell of claim 2, wherein, The body part is an elastic body, and in the axial direction, the ratio between the compression amount of the body part under the pressure of the second sealing member and the thickness of the body part in its natural state is greater than or equal to 0.1 and less than or equal to 0.

5.

4. The battery cell of claim 2, wherein, The second sealing member has a second recessed portion and an annular pressing surface surrounding the second recessed portion on its end face facing the body portion. The projection of the annular pressing surface along the axial direction at least partially surrounds the periphery of the injection hole, and the second sealing member presses the body portion through the annular pressing surface.

5. The battery cell of claim 4, wherein, The projection of the annular pressing surface along the axial direction is entirely located around the injection hole.

6. The battery cell of claim 4, wherein, In the axial direction, there is a height difference between the bottom of the second recess and the annular pressing surface, and the height difference is greater than the compression amount of the body portion when it is pressed by the second sealing member.

7. The battery cell of claim 6, wherein, The difference between the height difference and the compression amount is greater than or equal to 0.05 mm.

8. The battery cell of claim 4, wherein, In the radial direction, the radial dimension of the outer ring edge of the annular pressing surface is greater than or equal to the radial dimension of the outer peripheral surface of the body portion.

9. The battery cell of claim 4, wherein, In the radial direction, the difference between the radial dimension of the inner ring edge of the annular pressing surface and the radial dimension of the outer peripheral surface of the body is greater than or equal to 1 mm.

10. The battery cell of claim 4, wherein, The main body has a third recess on the side opposite to the injection hole, and the axial projection of the third recess falls inside the injection hole.

11. The battery cell of claim 10, wherein, The main body is provided with a protrusion on the side opposite to the injection hole, located around the third recess. The second sealing member is also provided with a fourth recess on the inner end face of the main body, located at the bottom of the second recess. The fourth recess is used to avoid the protrusion.

12. The battery cell of claim 2, wherein, The first sealing member further includes an insertion part, one end of which is connected to the main body and inserted into the injection hole.

13. The battery cell of claim 12, wherein, The insertion part is an elastic body, and the outer peripheral surface of the insertion part is sealed to the wall of the injection hole by a tight fit.

14. The battery cell of claim 13, wherein, In the radial direction, the difference between the radial dimension of the outer peripheral surface of the insertion part in its natural state and the radial dimension of the injection hole is greater than or equal to 0.2 mm and less than or equal to 0.8 mm.

15. The battery cell of claim 12, wherein, The first sealing member further includes a locking part, which is connected to the other end of the insertion part away from the body part. In the radial direction, the outer peripheral surface of the locking part protrudes from the outer peripheral surface of the insertion part and is used to abut against the side of the electrode terminal facing the inside of the housing when the insertion part is inserted into the injection hole.

16. The battery cell of claim 15, wherein, The insertion part and the locking part are elastic bodies. In their natural state, the difference between the maximum radial dimension of the outer peripheral surface of the locking part and the radial dimension of the outer peripheral surface of the insertion part is greater than or equal to 0.1 mm.

17. The battery cell of claim 16, wherein, In the axial direction, the thickness of the locking portion is greater than or equal to 0.5 mm.

18. The battery cell of claim 15, wherein, The locking part has a guide surface at one end opposite to the insertion part, and the guide surface is used to guide the locking part through the injection hole.

19. The battery cell of claim 18, wherein, On a reference section arranged along the axial direction, the guide surface has an inclination angle of 30° or greater and 60° or less relative to the axial direction.

20. The battery cell of any one of claims 1-19, wherein, The battery cell also includes a current collector and an electrode assembly disposed inside the housing. The current collector is used to connect the tabs of the electrode assembly and the electrode terminals. The electrode terminals are welded to the current collector in the area corresponding to the bottom of the first recess.

21. The battery cell of claim 20, wherein, The housing includes a shell and an end cap. One end of the shell has an opening, and the end cap closes to the opening. The shell includes a side wall and a bottom wall. The side wall surrounds the outside of the electrode assembly, and the bottom wall is disposed opposite to the opening. The wall portion is either the end cap or the bottom wall.

22. A battery, characterized by Includes the battery cell as described in any one of claims 1-21.

23. An electrical device, comprising: The electrical device includes the battery as described in claim 22.

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