Battery cell, battery device, energy storage system and power utilization device

Abstract

The utility model relates to the technical field of batteries, and discloses a single battery, a battery device, an energy storage system and a power utilization device, the single battery comprises a shell, an end cover and an electrode assembly, the shell is provided with a mounting space, the electrode assembly is arranged in the mounting space, and the end cover covers the mounting space and is electrically connected with the electrode assembly; the end cover comprises a cover body and an electrode terminal, the electrode terminal comprises a flange plate and a terminal body, the terminal body is connected with the flange plate, the flange plate is connected with the end cover, and the structural strength of the flange plate is higher than that of the terminal body. Therefore, the connection stability and reliability of the electrode terminal and the end cover are improved, and the reliability and safety of the battery monomer are further improved, and meanwhile, the size of the flange plate with higher structural strength can be set to be smaller, so that the space occupation of the electrode terminal is smaller, the energy density of the battery monomer can be set to be higher, and the battery monomer is more compact. And the reliability and the energy density are considered.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery monomer, a battery device, an energy storage system and an electric device. Background Art

[0002] In the related art, the electrode terminal is fixed on the end cover, and the internal pressure of the battery cell will act on the connection area between the electrode terminal and the end cover, causing the connection structure between the electrode terminal and the end cover to fail easily. In order to reduce the probability of failure, the size of the connection structure needs to be set larger, which will lead to a decrease in the energy density of the battery cell and make it difficult to balance the reliability and energy density of the battery cell. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the utility model is to provide a battery cell, a battery device, an energy storage system and an electrical device that can take into account both the reliability and energy density of the battery cell.

[0004] In the first aspect, the present application provides a battery cell, comprising: a shell, an end cover and an electrode assembly, the shell having an installation space, the electrode assembly being arranged in the installation space, the end cover being arranged in the installation space and being electrically connected to the electrode assembly; wherein the end cover comprises: a cover body and an electrode terminal, the electrode terminal comprises a flange and a terminal body, the terminal body is connected to the flange, the flange is connected to the end cover, and the structural strength of the flange is higher than the structural strength of the terminal body.

[0005] According to the battery cell of the embodiment of the present application, by constructing the electrode terminal as a split terminal body and a flange, and connecting with the end cover through the flange, the connection stability and reliability between the electrode terminal and the end cover are improved, thereby improving the reliability and safety of the battery cell. At the same time, the size of the flange with higher structural strength can be set smaller, so that the space occupied by the electrode terminal is smaller, and the energy density of the battery cell can be set higher to take into account both reliability and energy density.

[0006] According to some embodiments of the present application, the terminal body includes: a body segment and a flange portion arranged on the body segment, the flange plate is sleeved on the body segment, and the flange plate is connected to the flange portion.

[0007] In the above technical solution, by providing a flange portion on the main body segment and realizing the connection between the flange and the main body segment through the flange portion, such as welding, plugging, clamping and any other connection forms, the connection strength and reliability between the flange and the main body segment can be improved, thereby improving the structural strength and reliability of the electrode terminal.

[0008] According to some embodiments of the present application, there is at least one flange portion, and the flange portion is formed at an end of the body segment adjacent to the installation space and / or an end away from the installation space.

[0009] In the above technical scheme, in some embodiments, the flange can be clamped and fixed on both sides of the flange by two flange parts, and in other embodiments, the flange can be pushed against the limiting flange on one side of the flange by the flange part, that is, the structural limitation of the flange can be achieved through the flange part, and the pressure transmission released from the inside of the installation space to the outside is optimized, so that the internal pressure can be transmitted to the flange through the flange part, and further transmitted to the next flange part, or transmitted to the flange part through the flange, or transmitted to the flange through the flange part, so as to improve pressure concentration, further reduce the probability of connection failure between the electrode terminal and the end cover, and improve the reliability and safety of the battery cell.

[0010] According to some embodiments of the present application, there are two flange parts, which define a mounting groove, and the flange plate is constructed as a split piece and includes a plurality of arc-shaped plate segments, and the plurality of arc-shaped plate segments are all arranged in the mounting groove.

[0011] In the above technical solution, multiple arc-shaped disc segments can be disassembled and installed in the installation groove, and after the installation is completed, they can be assembled into an annular flange. This can avoid structural interference between the flange and the flange when assembling the flange, which may cause the flange to be unable to be installed, reduce the difficulty of assembling the flange, and improve the assembly efficiency.

[0012] According to some embodiments of the present application, the flange portion is one, the flange plate is constructed as an integral piece, and is sleeved on the body segment from one end of the body segment away from the flange portion.

[0013] In the above technical solution, after the integrated flange is assembled to the first section or the second section, the first section and the second section can be further assembled to avoid interference between the flange and the flange when assembling the flange, thereby reducing the difficulty of assembling the electrode terminal and improving assembly efficiency.

[0014] According to some embodiments of the present application, there are two flange parts, the main body section includes a first section and a second section, a flange part is formed on the first section, and another flange part is formed on the second section, the flange plate is constructed as an integral piece and is sleeved on the first section.

[0015] In the above technical solution, the flange portion can be formed at one end of the main body segment away from the installation space, and the flange plate is sleeved on the main body segment from the other end. The flange portion can also be formed at one end of the main body segment adjacent to the installation space, and the flange plate is sleeved on the main body segment from the other end. While satisfying the above technical effects, it can also reduce the difficulty of assembly and improve assembly efficiency.

[0016] According to some embodiments of the present application, the outer diameter of the main body section is D1, the maximum outer diameter of the flange portion is D2, and the following relation is satisfied: 0.4D2≤D1≤0.75D2.

[0017] In the above technical solution, the outer diameter of the main body section and the maximum outer diameter of the flange portion meet the above-mentioned ratio requirement, which can make the size of the main body section more reasonable. On the one hand, it can avoid the size of the main body section being too small, which may cause the local area of ​​the terminal body to be easily broken, so that the structural strength of the terminal body can meet the use requirements. On the other hand, the contact area between the flange portion and the flange plate can be kept stable to improve the connection strength and reliability between the flange portion and the flange portion, and can improve the mechanical transmission effect between the flange portion and the flange plate, reduce the probability of local deformation of the flange plate or the flange portion, and extend the service life and safety of the battery cell.

[0018] According to some embodiments of the present application, the minimum overlapping dimension between the flange portion and the flange plate is greater than W1 and equal to 1 mm.

[0019] According to some embodiments of the present application, the electrode terminal extends along a first direction, a dimension of the terminal body in the first direction is H1, a dimension of the flange in the first direction is H2, and the following conditions are satisfied: 0.1H1≤H2≤0.2H1.

[0020] In the above technical solution, the thickness of the flange can be set between 0.1 and 0.2 times the thickness of the terminal body. The thickness of the flange has less influence on the thickness of the terminal body. When designing the size of the terminal body, the flange size has less influence on the terminal size. Therefore, on the premise that the thickness of the flange meets the structural strength requirements, the size of the terminal body can be set smaller, thereby taking into account the energy density of the battery cell.

[0021] In a second aspect, the present application provides a battery device, including: a box body and a battery cell, wherein the battery cell is disposed in the box body.

[0022] In a third aspect, the present application provides an energy storage system, comprising: a power conversion device and a battery device, wherein the power conversion device is used to electrically connect the power generation device and the battery device.

[0023] In a fourth aspect, the present application provides an electrical device, including: a battery device.

[0024] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0026] Figure 1 is a schematic diagram of an electrical device according to an embodiment of the present application;

[0027] Figure 2 is a schematic diagram of a battery device according to an embodiment of the present application;

[0028] Figure 3 is a schematic diagram of an energy storage system according to an embodiment of the present application;

[0029] Figure 4 is a schematic diagram of a battery cell according to an embodiment of the present application;

[0030] Figure 5 is a schematic diagram of an end cap according to a first embodiment of the present application;

[0031] Figure 6 is a schematic diagram of a flange according to a first embodiment of the present application;

[0032] Figure 7 is a schematic diagram of an electrode terminal according to a first embodiment of the present application;

[0033] Figure 8 is a schematic diagram of an end cap according to a second embodiment of the present application;

[0034] Fig. 9 is a schematic diagram of a flange according to a second embodiment of the present application;

[0035] Fig.10 is a schematic diagram of an electrode terminal according to a second embodiment of the present application;

[0036] Fig.11 is a schematic diagram of an electrode terminal according to a third embodiment of the present application;

[0037] Fig.12 is a schematic diagram of an electrode terminal according to the fourth embodiment of the present application.

[0038] Reference numerals:

[0039] Battery cell 100,

[0040] Housing 10,

[0041] End cap 20, cover body 21, electrode terminal 22, flange 221, arc-shaped disc section 2211, terminal body 222, body section 2221, first section 22211, second section 22212, flange 2222, insulating member 23, pressure ring 24, sealing member 25,

[0042] The electrode assembly 30,

[0043] Box 200, battery device 300, power device 400, energy storage system 500, controller 600, motor 700,

[0044] Power generation device 510, power conversion device 520,

[0045] Installation slot a,

[0046] The first direction X. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0048] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0049] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

[0050] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0051] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0052] In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0053] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0054] In the description of the present invention, a first feature being “above” or “below” a second feature may include that the first and second features are directly in contact with each other, or may include that the first and second features are not in direct contact but are in contact with each other via another feature therebetween.

[0055] In the description of the present invention, a first feature “above”, “over” and “above” a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature.

[0056] The term “plurality” used in this application refers to two or more (including two).

[0057] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0058] The battery cell can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel hydrogen battery, a nickel cadmium battery, a lead storage battery, etc., which is not limited in the embodiments of the present application.

[0059] The battery apparatus mentioned in the embodiments of the present application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly may include multiple battery cells, which are connected in series, in parallel or in mixed connection through a busbar component.

[0060] In some embodiments, a battery cell assembly is generally formed by arranging a plurality of battery cells.

[0061] As an example, the battery cell assembly may be a battery module, which is formed by arranging and fixing a plurality of battery cells to form an independent module. As an example, the battery module may be formed by bundling a plurality of battery cells by a cable tie.

[0062] In some embodiments, the battery device may be a battery pack, which includes a case and one or more battery cell assemblies, wherein the battery cell assemblies are accommodated in the case.

[0063] As an example, the battery cell assembly may be a battery module, and the battery cell assembly may be accommodated in the box by fixing the battery module in the box.

[0064] As an example, the battery cell assembly may also be housed in the case by directly fixing a plurality of battery cells to the case.

[0065] As an example, the box may include a first box and a second box. The first box and the second box are buckled together to form a closed space inside the box to accommodate the battery cell assembly. The closed here means covered or closed, which can be sealed or unsealed. The first box can be a top cover or a bottom plate.

[0066] As an example, the box body may include a top cover, a frame and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, so that a closed space is formed inside the box body to accommodate the battery cell assembly.

[0067] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0068] The technical solutions described in the embodiments of the present application are applicable to various electrical devices that use battery cells, such as mobile phones, portable devices, laptop computers, electric vehicles, electric toys, electric tools, vehicles, ships and spacecraft, for example, spacecraft include airplanes, rockets, space shuttles and spacecraft, etc.

[0069] For the convenience of description, the following embodiments are described by taking the electric device as a vehicle as an example.

[0070] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application. A battery device 300 is provided inside the vehicle, and the battery device 300 can be provided at the bottom, head, or tail of the vehicle. The battery device 300 can be used to power the vehicle, for example, the battery device 300 can be used as an operating power source for the vehicle.

[0071] The vehicle may further include a controller 600 and a motor 700 . The controller 600 is used to control the battery device 300 to supply power to the motor 700 . The motor 700 serves as a load, for example, to meet the power requirements for starting, navigating and driving the vehicle.

[0072] In some embodiments of the present application, the battery device 300 can not only be used as an operating power source for the vehicle, but also as a driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0073] Please refer to Figure 2 , Figure 2 The exploded view of the battery device 300 provided in some embodiments of the present application. The battery device 300 includes a battery cell and a box 200, and the box 200 is used to accommodate the battery cell (ie, a battery module).

[0074] Among them, the box body 200 is a component for accommodating the battery unit. The box body 200 provides a placement space for multiple battery cells 100 in the battery unit. The box body 200 can adopt a variety of structures, and the battery cell 100 can be arranged in the placement space. As an example, the battery cell 100 can be a cylindrical battery cell 100, a prismatic battery cell 100 or a battery cell 100 of other shapes. There is no special limitation in the present application.

[0075] In the battery device 300, there can be one or more battery cells 100. If there are more than one battery cell 100, the multiple battery cells 100 can be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple battery cells 100 are both connected in series and in parallel. Multiple battery cells 100 can be connected in series, in parallel, or in mixed connection to form a battery unit, and then the multiple battery units are connected in series, in parallel, or in mixed connection to form a whole, and accommodated in the box 200. Alternatively, all battery cells 100 can be directly connected in series, in parallel, or in mixed connection, and then the whole formed by all battery cells 100 is accommodated in the box 200.

[0076] like Figure 3 As shown, Figure 3 A schematic diagram of the structure of an energy storage system 500 provided in some embodiments of the present application.

[0077] In some embodiments, the energy storage system 500 may include one or more battery devices 300 and a power converter 520 (PCS for short), and the power converter 520 is used to be connected between the power generation device 510 and the battery device 300. The power generation device 510 is used to generate electric energy, and the electric energy generated by the power generation device 510 can be stored in the battery device 300 through the power converter 520. As an example, the power generation device 510 can specifically be a solar panel, a hydroelectric power generation device 510, a thermal power generation device 510, a wind power generation device 510, etc. Among them, the specific type of the power generation device 510 is not limited in this application.

[0078] like Figure 4 As shown, Figure 4 A schematic diagram of the structure of a battery cell 100 provided in some embodiments of the present application.

[0079] The battery cell 100 is the smallest energy unit of the battery unit or the battery device 300 . The battery unit or the battery device 300 includes a plurality of battery cells 100 . The battery cell 100 includes a housing 10 , an end cap 20 , and an electrode assembly 30 disposed in the housing 10 .

[0080] The battery cell 100 includes: a shell 10, an end cover 20 and an electrode assembly 30. The shell 10 may include a bottom plate and a side plate. The side plate is arranged around the bottom plate and defines an installation space with an installation port. The electrode assembly 30 and other functional components can be arranged in the installation space. The end cover 20 covers the installation port of the shell 10 to isolate the internal space of the battery cell 100 from the external environment. The shape of the end cover 20 is compatible with the shape of the shell 10. The end cover 20 can be supported by a material with a certain hardness and strength (such as aluminum alloy, carbon fiber plate), and the end cover 20 can effectively protect the safety and reliability of the internal components of the shell 10 during extrusion and collision.

[0081] In some embodiments, the end cap 20 may also be provided with a pressure relief mechanism for releasing the internal pressure when the internal pressure or temperature of the battery cell 100 reaches a threshold value. The material of the end cap 20 may also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose any special restrictions on this. In some embodiments, an insulating member 23 may also be provided on the inner side of the end cap 20, and the insulating member 23 may be used to isolate the electrical connection components in the housing 10 from the end cap 20 to reduce the risk of short circuit. Exemplarily, the insulating member 23 may be plastic, rubber, etc.

[0082] The shell 10 is a component used to cooperate with the end cap 20 to form the internal space of the battery cell 100 (i.e., the installation space hereinafter), wherein the formed internal space can be used to accommodate the electrode assembly 30, the electrolyte and other components. The shell 10 and the end cap 20 can be independent components, and a mounting port can be set on the shell 10, and the internal space of the battery cell 100 is formed by covering the opening of the end cap 20 at the mounting port. The shell 10 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 10 can be determined according to the specific shape and size of the electrode assembly 30. The material of the shell 10 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this.

[0083] The electrode assembly 30 is a component in the battery cell 100 where electrochemical reactions occur. One or more electrode assemblies 30 may be included in the housing 10. The electrode assembly 30 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body of the electrode assembly 30, and the parts of the positive and negative electrode sheets without active materials each constitute a tab. The positive tab and the negative tab may be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery device 300, the positive active material and the negative active material react with the electrolyte, and the tabs are connected to the electrode terminals 22 to form a current loop.

[0084] However, in the related art, the electrode terminal 22 is arranged on the end plate, and the electrode terminal 22 is connected to the end plate through a connecting structure, such as: a connecting plate is integrally formed on the electrode terminal 22, and the connecting plate is connected to the end cover 20. In order to ensure the connection stability between the connecting plate and the end cover 20, reduce the probability of deformation or even breakage of the connecting plate after being subjected to the internal pressure of the battery cell 100, and improve the reliability and stability of the battery cell 100, it is necessary to set the thickness of the connecting plate to be larger. The thicker connecting plate will cause the overall height dimension of the electrode terminal 22 to be too large, which will reduce the energy density of the battery cell 100 and make it difficult to take both the energy density and reliability of the battery cell 100 into account.

[0085] Based on this, the present application proposes a battery cell 100, in which the terminal body 222 and the flange 221 are constructed as a split structure, and are connected to the end cover 20 through the flange 221 with higher structural strength, so as to improve the reliability and safety of the battery cell 100. The flange 221 with higher structural strength does not need to be set to a larger thickness to meet the connection strength requirements, and can correspondingly reduce the overall height dimension of the electrode terminal 22, thereby taking into account the energy density of the battery cell 100.

[0086] Reference below Figure 1-Figure 12 A battery cell 100 , a battery device 300 , an energy storage system 500 , and an electric device 400 according to an embodiment of the present invention are described.

[0087] like Figure 4 As shown, the present application provides a battery cell 100, including: a shell 10, an end cover 20 and an electrode assembly 30, the shell 10 has an installation space, the electrode assembly 30 is arranged in the installation space, the end cover 20 is covered in the installation space, and is electrically connected to the electrode assembly 30.

[0088] like Figure 5 , Figure 6 , Figure 7 and Figure 8 As shown, the end cover 20 includes: a cover body 21 and an electrode terminal 22, the electrode terminal 22 includes a flange 221 and a terminal body 222, the terminal body 222 is connected to the flange 221, the flange 221 is connected to the end cover 20, and the structural strength of the flange 221 is higher than the structural strength of the terminal body 222.

[0089] Specifically, the cover body 21 is used to cover the shell 10 (that is, the cover body 21 is covered on the installation opening of the shell 10). The cover body 21 and the shell 10 can be fixed in any form such as welding, screwing, and clamping, and the electrode assembly 30 can be fixed in the installation space, and the tabs of the electrode assembly 30 in the installation space (the positive pole tab and the negative pole tab are respectively at the positive terminal and the negative terminal) can be electrically connected to the electrode terminal 22, and the electrode terminal 22 is connected to external structures such as a bar and a bus to achieve charging and discharging.

[0090] Furthermore, an assembly hole can be formed on the end cover 20, and the electrode terminal 22 is installed in the assembly hole. The electrode terminal 22 includes a flange 221 and a terminal body 222. The terminal body 222 is used to achieve connection with the pole ear and external structures such as the bus bar and the bus bar, while the flange 221 is used to be fixedly connected to the end plate.

[0091] It can be understood that the electrode terminal 22 extends as a whole along the first direction, and based on the setting position of the electrode terminal 22, the first direction can be the height direction, length direction or width direction of the battery cell 100, and the extension size of the electrode terminal 22 along the first direction is negatively correlated with the energy density of the battery cell 100, that is, the larger the size of the electrode terminal 22, the lower the energy density of the battery cell 100, and the smaller the size of the battery terminal, the higher the energy density of the battery cell 100.

[0092] Exemplarily, the terminal body 222 of the embodiment of the present application extends along a first direction, and the flange 221 is connected to the terminal body 222 in a second direction perpendicular to the first direction. The structural strength of the flange 221 is higher than that of the terminal body 222. By connecting the flange 221 to the end cover 20, the connection strength and stability between the electrode terminal 22 and the end cover 20 can be improved, and the probability of deformation and fracture of the electrode terminal 22 during operation of the battery cell 100, resulting in failure of the battery cell 100, can be reduced. At the same time, based on the higher structural strength of the flange 221, while meeting the connection strength requirements, the size of the flange 221 in the first direction can be set smaller than the connection plate of the prior art, so that the overall size of the electrode terminal 22 in the first direction can be lower, so as to reduce the space occupied by the electrode terminal 22 in the first direction, thereby improving the energy density of the battery cell 100.

[0093] According to the battery cell 100 of the embodiment of the present application, the electrode terminal 22 is constructed as a split terminal body 222 and a flange 221, and is connected to the end cover 20 through the flange 221. While improving the connection stability and reliability between the electrode terminal 22 and the end cover 20, thereby improving the reliability and safety of the battery cell 100, the size of the flange 221 with higher structural strength can be set smaller, so that the space occupied by the electrode terminal 22 is smaller, and the energy density of the battery cell 100 can be set higher to take into account both reliability and energy density.

[0094] Combination Figure 7 , Fig.10 , Fig.11 and Fig.12 As shown, according to some embodiments of the present application, the terminal body 222 includes: a body section 2221 and a flange portion 2222 arranged on the body section 2221 , the flange plate 221 is sleeved on the body section 2221 , and the flange plate 221 is connected to the flange portion 2222 .

[0095] Specifically, the main body section 2221 can be generally cylindrical and extend along a first direction. The flange portion 2222 is formed on the main body section 2221 and extends along a second direction relative to the main body section 2221. The second direction is perpendicular to the first direction and can define a plane. The flange portion 2222 extends in the plane, and the projection of the flange portion 2222 in the first direction can be circular, triangular or rectangular, etc., and a circular contour is formed correspondingly at the center position, and the circular contour is the projection contour of the main body section 2221 in the first direction.

[0096] Therefore, by setting a flange portion 2222 on the main body segment 2221 and realizing the connection between the flange plate 221 and the main body segment 2221 through the flange portion 2222, such as: welding, plugging, clamping and other any connection forms, the connection strength and reliability between the flange plate 221 and the main body segment 2221 can be improved, thereby improving the structural strength and reliability of the electrode terminal 22.

[0097] like Figure 7 , Fig.10 , Fig.11 and Fig.12 As shown, according to some embodiments of the present application, there is at least one flange portion 2222 formed at one end of the body segment 2221 adjacent to the installation space and / or at one end away from the installation space.

[0098] Specifically, if Figure 7 and Fig.10 As shown, in some embodiments, there may be two flange portions 2222, which are respectively formed at one end of the body section 2221 adjacent to the installation space and at one end away from the installation space, so as to clamp the flange plate 221. Fig.11 As shown, in other embodiments, the flange portion 2222 may be one, which is formed at one end of the body section 2221 away from the installation space, so as to limit the flange 221 at a side of the flange 221 away from the installation space, such as Fig.12 As shown, in some other embodiments, the flange portion 2222 may be one, which is formed at one end of the body section 2221 adjacent to the installation space to limit the flange 221 at one side of the flange 221 adjacent to the installation space.

[0099] Thus, in some embodiments, the flange 221 can be clamped and fixed on both sides of the flange 221 by two flange portions 2222; in other embodiments, the flange 2222 can be pushed against the limiting flange 221 on one side of the flange 221, that is, the flange 2222 can also realize structural limitation of the flange 221, and optimize the transmission of pressure released outward from the inside of the installation space, so that the internal pressure can be transmitted to the flange 221 through the flange portion 2222, and further transmitted to the next flange portion 2222, or transmitted to the flange 2222 through the flange 221, or transmitted to the flange 221 through the flange portion 2222, so as to improve pressure concentration, further reduce the probability of connection failure between the electrode terminal 22 and the end cover 20, and improve the reliability and safety of the battery cell 100.

[0100] It should be pointed out that the number of flange portions 2222 can be one or two, the flange plate 221 can be constructed as an integral plate or a split plate, and the main body section 2221 can also be constructed as a split part. Based on this, the following four specific embodiments are used to specifically describe several optional structural forms of the electrode terminal 22 of the present application. It should be understood that these are only exemplary descriptions, and not an exhaustive list of the optional structural forms of the electrode terminal 22.

[0101] Combination Figure 5 , Figure 6 and Figure 7 As shown, in the first embodiment, there are two flange portions 2222, and the flange plate 221 is constructed as a split component.

[0102] Specifically, there are two flange portions 2222, and the two flange portions 2222 are arranged opposite to each other in the first direction and define an installation groove a. The flange plate 221 can be arranged in the installation groove a, and the flange plate 221 can be constructed as a split part and include multiple arc-shaped plate segments 2211, and the multiple arc-shaped plate segments 2211 are all arranged in the installation groove a.

[0103] In this way, multiple arc-shaped disc segments 2211 can be disassembled and installed in the installation groove a, and after the installation is completed, they can be assembled into a ring-shaped flange 221. This can avoid structural interference between the flange portion 2222 and the flange 221 when assembling the flange 221, which would cause the flange 221 to be unable to be installed, thereby reducing the difficulty of assembling the flange 221 and improving the assembly efficiency.

[0104] Combination Figure 8 , Fig. 9 and Fig.10 As shown, in the second embodiment, there are two flange portions 2222, and the main body segment 2221 is constructed as a split piece.

[0105] Specifically, there are two flange portions 2222, and the two flange portions 2222 are arranged opposite to each other in the first direction and define an installation groove a, and the flange plate 221 can be arranged in the installation groove a, and the main body section 2221 includes a first section 22211 and a second section 22212, a flange portion 2222 is formed on the first section 22211, and another flange portion 2222 is formed on the second section 22212, and the flange plate 221 is constructed as an integral piece and is sleeved on the first section 22211.

[0106] Among them, a flange portion 2222 is formed on both the first section 22211 and the second section 22212, and the first section 22211 and the second section 22212 can be detachably connected in the form of concave-convex matching, threaded matching, etc., and the flange 221 is sleeved on the first section 22211 along the first direction, and the first section 22211 and the second section 22212 are further assembled, or the flange 221 is sleeved on the second section 22212, and the second section 22212 and the first section 22211 are further assembled, and the flange 221 can be fixed between the two flange portions 2222.

[0107] Therefore, after the integrated flange 221 is assembled to the first section 22211 or the second section 22212, the first section 22211 and the second section 22212 can be further assembled to avoid interference between the flange 2222 and the flange 221 when assembling the flange 221, thereby reducing the difficulty of assembling the electrode terminal 22 and improving the assembly efficiency.

[0108] Of course, the structure of the body segment 2221 of the embodiment of the present application is not limited thereto. Fig.11 and Fig.12 As shown, in the third and fourth embodiments of the present application, the flange portion 2222 is one, the flange plate 221 is constructed as an integral piece, and one end of the body section 2221 away from the flange portion 2222 is sleeved on the body section 2221 .

[0109] That is to say, the flange portion 2222 can be formed at one end of the main body section 2221 away from the installation space, and the flange plate 221 is sleeved on the main body section 2221 from the other end. The flange portion 2222 can also be formed at one end of the main body section 2221 adjacent to the installation space, and the flange plate 221 is sleeved on the main body section 2221 from the other end. While satisfying the above-mentioned technical effects, it can also reduce the difficulty of assembly and improve the assembly efficiency.

[0110] like Figure 7 , Fig.10 , Fig.11 and Fig.12 As shown, according to some embodiments of the present application, the outer diameter of the main body section 2221 is D1, the maximum outer diameter of the flange portion 2222 is D2, and the following relation is satisfied: 0.4D2≤D1≤0.75D2.

[0111] Specifically, the main body section 2221 is generally cylindrical, and the flange portion 2222 is formed on the outer peripheral wall of the main body section 2221. The projection contour of the flange portion 2222 can be annular, and the outer surface contour of the flange portion 2222 can be in various shapes such as stepped and frustum-shaped. The outer diameter of the main body section 2221 is D1, which refers to the diameter of the terminal body 222 where the main body section 2221 participates in defining the mounting groove a portion, and the maximum outer diameter of the flange portion 2222 is D2, which refers to the diameter of the flange portion 2222 with the largest outer diameter area.

[0112] Exemplarily, the maximum outer diameter of the flange portion 2222 is 10 mm, and the outer diameter of the body segment 2221 may be 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, or 7.5 mm, etc.

[0113] In this way, the outer diameter of the main body section 2221 and the maximum outer diameter of the flange portion 2222 meet the above-mentioned ratio requirement, which can make the size of the main body section 2221 more reasonable. On the one hand, it can avoid the size of the main body section 2221 being too small, which may cause the local area of ​​the terminal body 222 to be easily broken, so that the structural strength of the terminal body 222 can meet the use requirements. On the other hand, the contact area between the flange portion 2222 and the flange plate 221 can be kept stable to improve the connection strength and reliability between the flange portion 2222 and the flange portion, and can improve the mechanical transfer effect between the flange portion 2222 and the flange plate 221, reduce the probability of local deformation of the flange plate 221 or the flange portion 2222, and extend the service life and safety of the battery cell 100.

[0114] Combination Figure 5 and Figure 8 As shown, according to some embodiments of the present application, the minimum overlapping dimension W1 between the flange portion 2222 and the flange plate 221 is greater than or equal to 1 mm.

[0115] That is to say, the projection contours of the flange portion 2222 and the flange plate 221 in the first direction at least partially overlap, and the length of the overlapping area in the second direction is greater than or equal to 1 mm, such as 1 mm, 2 mm, etc.

[0116] In this way, since the flange 221 is annular, the length of the overlapping area between the flange portion 2222 and the flange 221 in the second direction is greater than or equal to 2 mm, and the overlapping area is larger, which not only improves the connection stability and reliability of the flange portion 2222 and the flange 221, but also when mechanical transmission is performed between the flange portion 2222 and the flange 221 (i.e., transmitting the internal pressure released by the installation space), such as: flange portion 2222 to flange 221, or flange 221 to flange portion 2222, the mechanical transmission effect between the two is better and the transmission is more uniform, which can improve stress concentration, thereby reducing the probability of deformation of the flange 221 or the flange portion 2222, and improving the reliability and stability of the electrode terminal 22.

[0117] It should be pointed out that reducing the probability of deformation of the flange 221 and the flange portion 2222 can specifically achieve the following technical effects: reducing the probability of deformation of the flange 221 can reduce the probability of sealing failure, leakage, etc. in the connection area between the end cover 20 and the electrode terminal 22, so as to improve the working stability, reliability and safety of the battery cell 100; while reducing the probability of deformation of the flange portion 2222 can reduce the electrical connection stability between the terminal body 222 and the boundary component, and reduce the probability of poor connection between the terminal body 222 and structures such as the bar or bus, so as to reduce the probability of short circuit, open circuit and other problems, and improve the safety and reliability of the battery cell 100.

[0118] See also Figure 5 and Figure 8 As shown, according to some embodiments of the present application, the electrode terminal 22 extends along the first direction, the size of the terminal body 222 in the first direction is H1, the size of the flange 221 in the first direction is H2, and satisfies: 0.1H1≤H2≤0.2H1.

[0119] Exemplarily, the dimension of the terminal body 222 in the first direction is 10 mm, and the dimension of the flange 221 in the first direction may be 1 mm, 1.5 mm, 2 mm, etc.

[0120] That is to say, the thickness of the flange 221 can be set between 0.1 times and 0.2 times the thickness of the terminal body 222. The thickness of the flange 221 has a smaller impact on the thickness of the terminal body 222. When designing the size of the terminal body 222, the size of the flange 221 has a smaller impact on the terminal size. Therefore, on the premise that the thickness of the flange 221 meets the structural strength requirements, the size of the terminal body 222 can be set smaller, thereby taking into account the energy density of the battery cell 100.

[0121] It should be pointed out that in the prior art, the size ratio between the connection plate and the electrode terminal 22 is much larger than the size ratio between the terminal body 222 and the flange plate 221 of the present application.

[0122] like Figure 2 As shown, the present application provides a battery device 300 , including: a box body 200 and a battery cell 100 , wherein the battery cell 100 is disposed in the box body 200 .

[0123] like Figure 3 As shown, the present application provides an energy storage system 500 , including: a power conversion device 520 and a battery device 300 , wherein the power conversion device 520 is used to electrically connect a power generation device 510 and the battery device 300 .

[0124] like Figure 1 As shown, the present application provides an electric device 400 , including: a battery device 300 .

[0125] Next, combine Figure 5 and Figure 8 , the structure of the end cover 20 of the embodiment of the present application is described in detail.

[0126] like Figure 5 and Figure 8 As shown, the end cover 20 includes: a cover body 21, an electrode terminal 22, an insulating member 23, a pressure ring 24 and a sealing member 25. The electrode terminal 22 includes a flange 221 and a terminal body 222. After the flange 221 and the terminal body 222 are assembled, the flange 221 is fixed to the assembly hole of the end cover 20, and a sealing member 25 is arranged between the side of the terminal body 222 facing the installation space and the end cover 20. The flange 221 and the end cover 20 are pressed tightly by the pressure ring 24, and an insulating member 23 is arranged on the outside of the pressure ring 24. The insulating member 23 covers the pressure ring 24 and is arranged around the terminal body 222.

[0127] Therefore, the connection between the electrode terminal 22 and the end cover 20 is achieved through the flange 221, so that the flange 221 has higher strength, so that a lighter and thinner flange 221 can meet the connection requirements between the end cover 20 and the electrode terminal 22. At the same time, the structural size of the flange 221 has less restriction on the electrode terminal 22, so that the electrode terminal 22 can be reasonably adjusted in size based on the energy density and is no longer restricted by the size of the flange 221. Thereby achieving the technical goal of taking into account the energy density of the battery cell 100 while satisfying the connection strength between the end cover 20 and the electrode terminal 22 and improving the structural stability and reliability of the battery cell 100.

[0128] Other structures and operations of the battery cell 100, the battery device 300, the energy storage system 500 and the power consumption device 400 according to the embodiment of the present invention are known to those skilled in the art and will not be described in detail here.

[0129] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0130] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A battery cell, characterized in that: include: A shell (10), an end cover (20), and an electrode assembly (30), wherein the shell (10) has an installation space, the electrode assembly (30) is arranged in the installation space, and the end cover (20) is covered in the installation space and electrically connected to the electrode assembly (30); in The end cover (20) comprises: a cover body (21) and an electrode terminal (22); the electrode terminal (22) comprises a flange (221) and a terminal body (222); the terminal body (222) is connected to the flange (221); the flange (221) is connected to the end cover (20); and the structural strength of the flange (221) is higher than the structural strength of the terminal body (222).

2. The battery cell according to claim 1, characterized in that: The terminal body (222) comprises: a body section (2221) and a flange portion (2222) arranged on the body section (2221); the flange plate (221) is sleeved on the body section (2221), and the flange plate (221) is connected to the flange portion (2222).

3. The battery cell according to claim 2, characterized in that: There is at least one flange portion (2222), and it is formed at one end of the body section (2221) adjacent to the installation space, and / or at one end away from the installation space.

4. The battery cell according to claim 3, characterized in that: There are two flange portions (2222) and they define a mounting groove (a); the flange plate (221) is constructed as a split part and comprises a plurality of arc-shaped plate segments (2211); and the plurality of arc-shaped plate segments (2211) are all arranged in the mounting groove (a).

5. The battery cell according to claim 3, characterized in that: The flange portion (2222) is one, and the flange plate (221) is constructed as an integral piece, and is sleeved on the body section (2221) from one end of the body section (2221) away from the flange portion (2222).

6. The battery cell according to claim 3, characterized in that: There are two flange portions (2222), and the main body section (2221) includes a first section (22211) and a second section (22212), one flange portion (2222) is formed on the first section (22211), and another flange portion (2222) is formed on the second section (22212), and the flange plate (221) is constructed as an integral piece and is sleeved on the first section (22211).

7. The battery cell according to any one of claims 2 to 6, characterized in that: The outer diameter of the main body section (2221) is D1, the maximum outer diameter of the flange portion (2222) is D2, and the following condition is satisfied: 0.4D2≤D1≤0.75D2.

8. The battery cell according to any one of claims 2 to 6, characterized in that: The minimum overlapping dimension W1 between the flange portion (2222) and the flange plate (221) is greater than or equal to 1 mm.

9. The battery cell according to any one of claims 1 to 6, characterized in that: The electrode terminal (22) extends along a first direction, the dimension of the terminal body (222) in the first direction is H1, the dimension of the flange (221) in the first direction is H2, and the following conditions are satisfied: 0.1H1≤H2≤0.2H1.

10. A battery device, characterized in that: include: Box; The battery cell according to any one of claims 1 to 9, wherein the battery cell is arranged in the box body.

11. An energy storage system, characterized in that: include: A power conversion device (520) and a battery device as claimed in claim 10, wherein the power conversion device (520) is used to electrically connect a power generation device (510) and the battery device.

12. An electrical device, characterized in that: include: The battery device according to claim 10.

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