Battery device and electric device

Abstract

The application provides a battery device and an electric device. The battery device comprises a box body and a plurality of battery groups. The box body has a containing cavity. The plurality of battery groups are arranged in the containing cavity and arranged in a first direction. Each battery group comprises a plurality of battery cells arranged in a second direction. The battery cell comprises a shell, an electrode assembly and two electrode terminals. The two electrode terminals are arranged at two ends of the shell in the second direction. The electrode assembly comprises a main body and two tabs. In the second direction, a containing space is arranged between each electrode terminal and the main body. The two tabs are respectively led out from the two ends of the main body in the second direction. At least part of the tab is arranged in the containing space and electrically connected to the electrode terminal. The ratio of the sum of the sizes of all the containing spaces of the battery group in the second direction to the size of the containing cavity in the second direction is 2%-7%. The application can improve the energy density of the battery device.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a battery device and an electrical device. Background Technology

[0002] With the development of new energy technologies, battery devices are being used more and more widely, such as in mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and power tools.

[0003] In the development of battery technology, improving the energy density of battery devices has always been a research direction. Summary of the Invention

[0004] In view of the above problems, this application provides a battery device and an electrical device that can improve the energy density of the battery device.

[0005] In a first aspect, this application provides a battery device, comprising a housing and multiple battery packs. The housing has a receiving cavity. Multiple battery packs are disposed in the receiving cavity and arranged along a first direction. Each battery pack includes multiple battery cells arranged along a second direction, the first direction being perpendicular to the second direction and parallel to the thickness direction of the battery cells. The dimension of the receiving cavity along the first direction is larger than the dimension of the receiving cavity along the second direction. Each battery cell includes a casing, an electrode assembly, and two electrode terminals, respectively disposed at both ends of the casing along the second direction. The electrode assembly includes a main body and two tabs. In the second direction, a receiving space is provided between each electrode terminal and the main body. The two tabs extend from both ends of the main body along the second direction, and at least a portion of the tabs is disposed in the receiving space and electrically connected to the electrode terminals. The ratio of the sum of the dimensions of all the receiving spaces of the battery pack along the second direction to the dimension of the receiving cavity along the second direction is 2%-7%.

[0006] In the above scheme, the ratio of the sum of the dimensions of all the housing spaces of the battery pack along the second direction to the dimensions of the housing cavity along the second direction is limited to between 2% and 7% in order to balance the space utilization rate of multiple battery cells in the housing cavity in the first and second directions, thereby increasing the total capacity of multiple battery cells in the housing cavity and thus increasing the energy density of the battery device.

[0007] In some embodiments, the dimension of the accommodating space along the second direction is W3, and the dimension of the battery cell along the second direction is W4: 2.3% ≤ 2W3 / W4 ≤ 6.5%.

[0008] In the above scheme, by limiting 2W3 / W4 to greater than or equal to 2.3%, the space size for arranging the tabs is increased, thereby increasing the size of the battery cell in the first direction and increasing the space utilization rate of the battery cell in the first direction within the housing. By limiting 2W3 / W4 to less than or equal to 6.5%, the size of the battery cell in the first direction is controlled, increasing the number of battery cells arranged in the first direction within the housing and reducing the number of battery cells arranged in the second direction within the housing, thereby improving the space utilization rate of the battery cell in the second direction within the housing.

[0009] In some embodiments, the number of battery cells in the battery pack is 2 to 4, so as to reduce the impact of the housing space on the battery device in the second direction and improve the space utilization of the battery cells in the second direction within the housing.

[0010] In some embodiments, the dimension of the receiving cavity along the first direction is L1, and the dimension of the battery cell along the first direction is L2; ​​55≤L1 / L2≤90.

[0011] In the above scheme, by limiting the number of arrangeable battery cells to greater than or equal to 55, the number of battery cells arranged in the second direction within the housing cavity is reduced, thereby improving the space utilization rate of battery cells in the housing along the second direction; by limiting the number of arrangeable battery cells to less than or equal to 90, the number of battery cells arranged in the first direction within the housing cavity is reduced, thereby improving the space utilization rate of battery cells in the housing along the first direction.

[0012] In some embodiments, the housing includes two first walls disposed opposite each other along a first direction and two second walls disposed opposite each other along a second direction, with each first wall connecting to the two second walls, thereby simplifying the production and assembly process of the housing, reducing manufacturing costs, and the four walls being interconnected to form a closed rigid frame, which can effectively disperse external impacts or pressures and reduce the possibility of local stress concentration.

[0013] In some embodiments, the thickness of the first wall is less than the thickness of the second wall.

[0014] In the above scheme, the above settings make the first wall more prone to elastic deformation, thereby absorbing some of the stress caused by volume changes, reducing the possibility of shell cracking or extrusion damage to the electrode assembly, and also reducing the amount of shell material used and the overall weight of the battery cell. Meanwhile, the second wall needs to be provided with electrode terminals, which can provide support for the electrode terminals, reducing the possibility of electrode terminal deformation or breakage due to vibration, collision or internal expansion, and improving the reliability of the battery cell.

[0015] In some embodiments, the thickness of the first wall is 0.3mm-0.8mm, and the thickness of the second wall is 1.2mm-2.5mm.

[0016] The above scheme, through the above settings, helps to reduce the overall weight of the battery cell, increase the mass energy density of the battery cell, and achieve lightweighting of the battery device.

[0017] In some embodiments, the sum of the thicknesses of all the second walls of the battery pack is t1; 0.2% ≤ t1 / W1 ≤ 1%.

[0018] In the above scheme, the above arrangement helps to reduce the space occupied by the second wall in the second direction of the cavity, improve the energy density, and at the same time ensure the support capacity for the electrode terminals, reduce the possibility of deformation of the electrode terminals, and improve the reliability of the battery cell.

[0019] In some embodiments, the number of battery packs is m, the dimension of the receiving cavity along the first direction is L1, and the thickness of the first wall is t2; 1% ≤ 2 × m × t2 / L1 ≤ 3%.

[0020] In the above scheme, the above arrangement helps to reduce the space occupied by the first wall in the first direction of the cavity, increase the energy density, enhance the mechanical strength of the first wall, reduce the possibility of permanent deformation or cracking of the shell, and improve the reliability of the battery cell.

[0021] In some embodiments, the battery cell further includes a pressure relief mechanism, and the housing includes a third wall and a fourth wall disposed opposite to each other along a third direction. The pressure relief mechanism is disposed on the third wall, and the thickness of the third wall is greater than or equal to the thickness of the fourth wall.

[0022] In the above scheme, the mechanical strength of the third wall is increased, the possibility of deformation of the third wall during the actuation of the pressure relief mechanism leading to deformation or even blockage of the exhaust passage is reduced, and the reliability of pressure relief is improved.

[0023] In some embodiments, the thickness of the third wall is 1.2mm-2.0mm, and the thickness of the fourth wall is 0.3mm-0.8mm.

[0024] The above scheme, through the above settings, helps to reduce the overall weight of the battery cell, increase the mass energy density of the battery cell, and achieve lightweighting of the battery device.

[0025] In some embodiments, the dimension of the receiving cavity along the first direction is L1, where 1300mm≤L1≤2100mm and 1000mm≤W1≤1400mm.

[0026] In the above scheme, the above settings enable the standardization of battery device size, reduce the development cost of multiple battery cells, improve production efficiency, optimize space utilization based on the number of battery cells to be arranged as needed, and improve the energy density of the battery device.

[0027] In some embodiments, the housing includes a shell and two end caps. The shell has an opening along a second direction, and the two end caps are respectively connected to both ends of the shell along the second direction and cover the opening. The end caps are second walls, and the shell includes a first wall.

[0028] In the above scheme, the end cap typically has a greater thickness than the housing. Placing the electrode terminals on the end cap increases the connection strength between the first electrode terminal and the end cap, improves the stability of the electrode terminals, and reduces the risk of electrode terminal misalignment.

[0029] In some embodiments, the housing includes two second walls disposed opposite each other along a second direction. The battery cell also includes an insulating member located on the side of the second wall facing the main body. The insulating member includes an insulating body and a first protrusion extending from the insulating body on the side facing the main body. The distance between the surface of the main body facing the insulating body and the surface of the insulating body facing the main body is greater than or equal to the dimension of the receiving space along the second direction.

[0030] In the above scheme, the above settings help to reduce the possibility of interference between the connection structure and the insulation body between the tab and the electrode terminal, and improve the connection reliability between the tab and the electrode terminal.

[0031] In some embodiments, the housing further includes a beam structure disposed in the receiving cavity and dividing the receiving cavity into multiple sub-cavities, the multiple sub-cavities being arranged sequentially along a first direction, and each sub-cavity accommodating at least one battery pack.

[0032] In the above scheme, during use, the battery cells expand and deform, especially the expansion deformation in the first direction is large. The beam structure can deform, thereby absorbing some of the stress caused by the volume change, reducing the possibility of rupture caused by mutual compression between battery cells, and improving the reliability of the battery device.

[0033] Secondly, embodiments of this application provide an electrical device, including the battery device in any of the foregoing embodiments, the battery device being used to provide electrical energy.

[0034] 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 Figure Description

[0035] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the structure of a vehicle provided in an embodiment of this application;

[0037] Figure 2 This is an exploded structural diagram of a battery device provided in an embodiment of this application;

[0038] Figure 3 This is a schematic diagram of the exploded structure of a single battery cell provided in an embodiment of this application;

[0039] Figure 4 This is a schematic cross-sectional view of a battery cell provided in an embodiment of this application;

[0040] Figure 5 yes Figure 4 A schematic diagram of an enlarged structure of P;

[0041] Figure 6 This is a cross-sectional structural diagram of a battery device provided in an embodiment of this application;

[0042] Figure 7 This is a cross-sectional structural schematic diagram of another battery device provided in the embodiments of this application;

[0043] Figure 8 This is a cross-sectional structural schematic diagram of another battery device provided in the embodiments of this application;

[0044] Figure 9 This is a cross-sectional structural diagram of another battery cell provided in the embodiments of this application;

[0045] Figure 10 This is a cross-sectional structural diagram of another battery cell provided in the embodiments of this application;

[0046] Figure 11 This is a cross-sectional structural schematic diagram of another battery device provided in the embodiments of this application.

[0047] Marker description

[0048] 1000, Vehicle; 100, Battery unit; 200, Control system; 300, Motor;

[0049] 10. Box body; 11. First box body section; 12. Second box body section; 13. Receiving cavity; 14. Beam structure;

[0050] 20. Battery cell; 21. Casing; 21a. Shell; 21b. End cap; 211. First wall; 212. Second wall; 213. Third wall; 214. Fourth wall; 22. Electrode assembly; 221. Main body; 222. Tab; 23. Electrode terminal; 24. Receiving space; 25. Pressure relief mechanism; 26. Insulating component; 261. Insulating body; 262. First protrusion; G. Battery pack;

[0051] X, first direction; Y, second direction; Z, third direction. Detailed Implementation

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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).

[0058] 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.

[0059] 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.

[0060] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0061] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0062] The battery device mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells, which are connected in series, parallel, or mixed connections via a busbar.

[0063] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells; as an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells into a single module. As an example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0064] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cell assemblies housed within the housing.

[0065] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0066] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0067] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0068] In some embodiments, the battery device may be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0069] With the development of new energy technologies, batteries are being used more and more widely, for example in mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and power tools.

[0070] In the development of battery technology, the energy density of battery devices directly affects the driving range, system energy density, and user experience of end products.

[0071] In current battery devices, multiple battery cells are connected in series and arranged sequentially within the housing to achieve higher energy density. In existing arrangements, multiple battery cells are arranged in rows and columns, with the number of rows and columns adjusted based on factors such as the internal space of the housing and the size of the battery cells. How to improve the arrangement of battery cells within the housing to increase the energy density of the battery device has always been an important research direction in battery technology.

[0072] Based on the above-mentioned technical problems, this application provides a technical solution that limits the ratio of the size of the housing space along the second direction to the size of the housing cavity along the second direction in the battery pack to between 0.8% and 2.0%, so as to balance the space utilization rate of multiple battery cells in the housing cavity in the first and second directions, thereby increasing the total capacity of multiple battery cells in the housing cavity and thus increasing the energy density of the battery device.

[0073] The technical solutions described in this application are applicable to battery devices and electrical devices using battery devices. Electrical devices include, for example, mobile phones, portable devices, laptops, electric vehicles, electric cars, ships, spacecraft, electric toys, and power tools. Spacecraft include, for example, airplanes, rockets, space shuttles, and spacecraft. Electric toys include, for example, stationary or mobile electric toys, specifically, game consoles, electric car toys, electric ship toys, and electric airplane toys. Power tools include, for example, metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, specifically, electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers.

[0074] The battery cells described in this application are not limited to the electrical devices described above, but for the sake of brevity, the following embodiments are all illustrated using electric vehicles as an example.

[0075] Please see Figure 1 , Figure 1 This is a schematic diagram of a vehicle structure provided in an embodiment of this application. The vehicle 1000 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 device 100 can be installed inside the vehicle 1000; specifically, for example, the battery device 100 can be installed at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, the battery device 100 can serve as the operating power source for the vehicle 1000. The vehicle 1000 may also include a control system 200 and a motor 300. The control system 200, for example, is used to control the battery device to supply power to the motor 300. The battery device can be used for starting the vehicle 1000, navigation, etc. Of course, the battery device 100 can also be used to drive the vehicle 1000, replacing or partially replacing gasoline or natural gas to provide propulsion for the vehicle 1000.

[0076] Figure 2 This is an exploded structural diagram of a battery device provided in an embodiment of this application. Figure 2 As shown, the battery device 100 includes a housing 10 and a battery cell 20 (not shown in the figure), with the battery cell 20 housed within the housing 10.

[0077] The housing 10 is used to accommodate the battery cell 20, and the housing 10 can have various structures. In some embodiments, the housing 10 may include a first housing portion 11 and a second housing portion 12, which overlap each other, and together define a receiving cavity 13 for accommodating the battery cell 20. The second housing portion 12 may be a hollow structure with one end open, and the first housing portion 11 may be a plate-like structure, covering the open side of the second housing portion 12 to form a housing 10 with the receiving cavity 13; alternatively, both the first housing portion 11 and the second housing portion 12 may be hollow structures with one side open, with the open side of the first housing portion 11 covering the open side of the second housing portion 12 to form a housing 10 with the receiving cavity 13. Of course, the first housing portion 11 and the second housing portion 12 can have various shapes, such as cylinders, cuboids, etc.

[0078] In the battery device 100, there can be multiple battery cells 20. These multiple battery cells 20 can be connected in series, parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells 20 are connected in both series and parallel connections. Multiple battery cells 20 can be directly connected in series, parallel, or in a mixed configuration, and then the entire assembly of the multiple battery cells 20 is housed within the housing 10. Alternatively, multiple battery cells 20 can first be connected in series, parallel, or in a mixed configuration to form a battery module, and then multiple battery modules can be connected in series, parallel, or in a mixed configuration to form a whole, which is then housed within the housing 10.

[0079] Figure 3 This is a schematic diagram of the exploded structure of a single battery cell provided in an embodiment of this application. Figure 4 This is a cross-sectional structural diagram of a battery cell provided in an embodiment of this application. Figure 5 yes Figure 4 A schematic diagram of an enlarged structure of P. Figure 6 This is a cross-sectional structural diagram of a battery device provided in an embodiment of this application.

[0080] Please see Figures 2 to 6 In some embodiments, the battery cell 20 includes a housing 21 and an electrode assembly 22, the electrode assembly 22 being housed within the housing 21. The housing 21 is a hollow structure, with an internal space 24 for accommodating the electrode assembly 22 and the electrolyte. The shape of the housing 21 can be determined according to the specific shape of the electrode assembly 22. For example, if the electrode assembly 22 is a cuboid structure, a cuboid housing 21 can be used.

[0081] The outer shell 21 is a hollow structure, and its interior forms a receiving space 24 for accommodating the electrode assembly 22 and the electrolyte. The shape of the outer shell 21 can be determined according to the specific shape of the electrode assembly 22. For example, if the electrode assembly 22 has a cuboid structure, then a cuboid outer shell 21 can be selected.

[0082] Electrode assembly 22 is a component in the battery cell 20 where electrochemical reactions occur. The housing 21a may contain one or more electrode assemblies 22.

[0083] In some embodiments, the electrode assembly 22 includes a positive electrode and a negative electrode. During the charging and discharging process of the battery cell 20, active ions (e.g., lithium ions) are inserted and extracted back and forth between the positive and negative electrode.

[0084] In some embodiments, the electrode assembly 22 further includes a separator membrane disposed between the positive electrode and the negative electrode, which can prevent short circuit between the positive and negative electrodes, while allowing active ions to pass through.

[0085] In some embodiments, the positive electrode may include a positive current collector and a positive electrode film layer disposed on at least one surface of the positive current collector. Exemplarily, the portion of the positive current collector without the positive electrode film layer may serve as a positive electrode tab 222.

[0086] As an example, the positive electrode current collector has two surfaces opposite each other in its own thickness direction, and the positive electrode film layer is disposed on either or both of the two opposite surfaces of the positive electrode current collector. Optionally, the positive electrode film layer may include a positive electrode active material layer.

[0087] In some embodiments, the negative electrode sheet may include a negative electrode current collector and a negative electrode film layer disposed on at least one surface of the negative electrode current collector. Exemplarily, the portion of the negative electrode current collector without the negative electrode film layer may serve as a negative electrode tab 222. Optionally, the negative electrode film layer may include a negative electrode active material layer.

[0088] In some embodiments, the electrode assembly 22 includes a main body 221, a positive electrode tab 222, and a negative electrode tab 222. The positive electrode tab 222 and the negative electrode tab 222 extend from the main body 221.

[0089] As an example, the positive electrode sheet has a portion coated with a positive electrode film layer for the positive current collector, a portion coated with a negative electrode film layer for the negative current collector, a positive electrode film layer, a negative electrode film layer, and a separator film constituting the electrode body. The positive electrode tab 222 and the negative electrode tab 222 can be led out from the same end of the main body portion 221, or they can be led out from both ends of the main body portion 221 respectively.

[0090] In some embodiments, the electrode assembly 22 is a wound structure. The positive electrode and the negative electrode are wound into a wound structure.

[0091] As an example, the separator can be continuously installed between any adjacent positive or negative electrode plates by folding or rolling.

[0092] Please see Figures 2 to 6This application provides a battery device 100, which includes a housing 10 and multiple battery packs G. The housing 10 has a receiving cavity 13. The multiple battery packs G are disposed in the receiving cavity 13 and arranged along a first direction X. Each battery pack G includes multiple battery cells 20 arranged along a second direction Y. The first direction X is perpendicular to the second direction Y and parallel to the thickness direction of the battery cells 20. The dimension of the receiving cavity 13 along the first direction X is larger than the dimension of the receiving cavity 13 along the second direction Y. The battery cell 20 includes a housing 21, an electrode assembly 22, and two electrode terminals 23. The two electrode terminals 23 are respectively disposed at both ends of the housing 21 along the second direction Y. The electrode assembly 22 includes a main body 221 and two tabs 222. In the second direction Y, a receiving space 24 is provided between each electrode terminal 23 and the main body 221. The two tabs 222 are respectively led out from both ends of the main body 221 along the second direction Y. At least a portion of the tabs 222 is disposed in the receiving space 24 and electrically connected to the electrode terminals 23. The ratio of the sum of the dimensions of all the housing spaces 24 of the battery pack G along the second direction Y to the dimension of the housing cavity 13 along the second direction Y is 2%-7%.

[0093] As an example, the receiving cavity 13 within the housing 10 can be formed along a first direction X and a second direction Y. For instance, the receiving cavity 13 may be rectangular along the first direction X and the second direction Y. Alternatively, the dimension of the receiving cavity 13 along the first direction X can gradually decrease; for instance, the receiving cavity 13 may be trapezoidal along the first direction X and the second direction Y. Optionally, the dimension of the receiving cavity 13 along the first direction X can be several times greater than the dimension of the receiving cavity 13 along the second direction Y.

[0094] Optionally, the outer contour shape of the housing 10 can be the same as the shape of the receiving cavity 13, or it can be different.

[0095] In some examples, the battery sizes within the same battery pack G can be the same or different.

[0096] In some examples, the number and size of the individual battery cells 20 in different battery packs G may be the same or different.

[0097] In some examples, the thickness direction of the battery cell 20 may refer to the battery cell 20 including the electrode assembly 22, the electrode assembly 22 including multilayer electrodes, and the stacking direction of the multilayer electrodes being the thickness direction of the battery cell 20.

[0098] For example, the battery cell 20 has a first end and a second end along the second direction Y. The first end and the second end may also be the two ends of the housing 21 along the second direction Y. The first end and the second end may also be the two ends of the main body 221 along the second direction Y.

[0099] Two tabs 222 extend from the main body 221 at both ends along the second direction Y. This can be understood as one tab 222 extending from the first end in a direction away from the second end. The polarities of the two tabs 222 can be opposite; that is, one tab 222 is the positive tab 222, and the other is the negative tab 222. The first end of the positive tab 222 extends in a direction away from the second end, and the negative tab 222 extends from the second end in a direction away from the first end. Alternatively, the positive tab 222 may also include a first positive sub-tab 222 and a second positive sub-tab 222. The first positive sub-tab 222 extends from the first end in a direction away from the second end, and the second positive tab 222 extends from the second end in a direction away from the first end. And / or, the negative electrode tab 222 may also include a first negative electrode tab 222 and a second negative electrode tab 222, wherein the first negative electrode tab 222 extends from the first end in a direction away from the second end, and the second negative electrode tab 222 extends from the second end in a direction away from the first end.

[0100] Two electrode terminals 23 are respectively disposed at both ends of the outer casing 21 along the second direction Y. It can be understood that both ends of the outer casing 21 along the second direction Y are provided with electrode terminals 23. The electrode terminal 23 disposed at the first end of the outer casing 21 is electrically connected to the tab 222 led out from the first end of the main body 221, and the electrode terminal 23 disposed at the second end of the outer casing 21 is electrically connected to the tab 222 led out from the second end of the main body 221.

[0101] For example, the positive electrode tab is led out from the first end of the main body 221 and is electrically connected to the electrode terminal 23 disposed at the first end of the housing 21, and the negative electrode tab is led out from the second end of the main body 221 and is electrically connected to the electrode terminal 23 disposed at the second end of the housing 21.

[0102] For example, the positive electrode tab may further include a first positive sub-tab and a second positive sub-tab. The first positive sub-tab extends from the first end of the main body 221, and the electrode terminal 23 located at the first end of the housing 21 includes a first positive electrode terminal 23. The first positive sub-tab is electrically connected to the first positive electrode terminal 23. The second positive electrode tab extends from the second end of the main body 221, and the electrode terminal 23 located at the second end of the housing 21 includes a second positive electrode terminal 23. The second positive electrode tab is electrically connected to the second positive electrode terminal 23. And / or, the negative electrode tab may further include a first negative sub-tab and a second negative electrode tab. The first negative electrode tab is led out from the first end of the main body 221. The electrode terminal 23 located at the first end of the outer shell 21 also includes a first negative electrode terminal 23. The first negative electrode terminal 23 and the first positive electrode terminal 23 are insulated from each other. The first negative electrode tab is electrically connected to the first negative electrode terminal 23. The second negative electrode tab is led out from the second end of the main body 221. The second negative electrode terminal 23 and the second positive electrode terminal 23 are insulated from each other. The electrode terminal 23 located at the second end of the outer shell 21 also includes a second negative electrode terminal 23. The second negative electrode tab is electrically connected to the second negative electrode terminal 23.

[0103] Of course, the tab 222 located at one end of the main body 221 may also include two sub-tabs 222 of the same polarity. For example, the main body 221 includes 100 layers of electrode sheets of the same polarity stacked together, wherein the tabs 222 connected to the odd-numbered layers of electrode sheets are stacked to form a sub-tab, and the tabs 222 connected to the even-numbered layers of electrode sheets are stacked to form a sub-tab; or, the tabs 222 connected to the 50 layers of electrode sheets are stacked to form a sub-tab. It is understood that these two sub-tabs are spaced apart, and these two sub-tabs are electrically connected to the same electrode terminal 23, thereby reducing the thickness of each sub-tab and reducing the heat generated during the operation of the sub-tabs.

[0104] As an example, electrode terminal 23 may be a separately formed component that is mounted on housing 21. Alternatively, electrode terminal 23 may also be part of housing 21.

[0105] In the second direction Y, there is a receiving space 24 between each electrode terminal 23 and the main body 221. It can be understood that a part of the structure of the electrode terminal 23 is located inside the housing 21. The part of the electrode terminal 23 located inside the housing 21 is used to electrically connect with the tab 222. The space between the plane of the surface of the electrode terminal 23 facing the main body 221 and the plane of the surface of the main body 221 facing the electrode terminal 23 is the receiving space 24.

[0106] In some examples, the entire structure of the tab 222 is disposed in the receiving space 24. In other examples, the dimension of the space between the inner wall of the housing 21 for arranging the electrode terminal 23 and the main body 221 in the second direction Y is greater than the dimension of the receiving space 24 in the second direction Y. A part of the tab 222 is located in the receiving space 24, and another part of the tab 222 is located in the space between the inner wall of the housing 21 for arranging the electrode terminal 23 and the main body 221.

[0107] For example, the dimension of the receiving cavity along the second direction can be W1, and the sum of the dimensions of all the receiving spaces of the battery pack along the second direction can be W2.

[0108] When the dimension of the receiving cavity 13 along the first direction X is fixed, an increase in the dimension of a single receiving space 24 along the second direction Y means an increase in the thickness of the electrode tabs 222, which in turn increases the number of electrode plates in the electrode assembly 22. This increases the thickness of the battery cell 20 (the dimension of the battery cell 20 along the first direction X). Since the dimension of the receiving cavity 13 along the first direction X is fixed, the increased thickness of the battery cell 20 leads to a decrease in the number of battery cells 20 arranged along the first direction X. This reduces the space occupied by the casing 21 of the battery cell 20 in the first direction X, thereby improving the space utilization rate of the battery cell 20 within the housing 10 along the first direction X. In other words, the dimension of a single receiving space 24 along the second direction Y and the space utilization rate of multiple battery cells 20 within the housing 10 along the first direction X are positively correlated. Conversely, when the dimension of a single receiving space 24 along the second direction Y decreases, the space utilization rate of the battery cell 20 within the housing 10 along the first direction X decreases.

[0109] When the dimensions of the receiving cavity 13 along the first direction X and the second direction Y are fixed, and the number of battery cells 20 is also fixed, an increase in the dimension of a single receiving space 24 along the second direction Y leads to an increase in the space occupied by the receiving space 24 in the first direction X. Furthermore, since the number of battery cells 20 arranged along the first direction X decreases, the number of battery cells 20 arranged along the second direction Y increases, thus increasing the value of W2 and reducing the space utilization rate of the battery cells 20 within the housing 10 along the second direction Y. In other words, both the dimension of a single receiving space 24 along the second direction Y and the number of battery cells 20 arranged along the second direction Y are negatively correlated with the space utilization rate of multiple battery cells 20 within the housing 10 along the second direction Y. Conversely, when the dimension of a single receiving space 24 along the second direction Y decreases, the number of battery cells 20 arranged along the second direction Y decreases, and the space utilization rate of the battery cells 20 within the housing 10 along the second direction Y increases.

[0110] For example, W2 / W1 can be 2%, 2.1%, 2.3%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, or 7%.

[0111] It is understandable that each battery cell 20 has electrode terminals 23 and tabs 222 at both ends along the second direction Y, so that each battery cell 20 has two receiving spaces 24. The sum of the dimensions of all the receiving spaces 24 along the second direction Y in the battery pack G refers to the sum of the dimensions of the two receiving spaces 24 along the second direction Y in all the battery cells 20 within the battery pack G. Based on the above, it can be seen that the dimension of a single receiving space 24 along the second direction Y and the number of battery cells 20 arranged along the second direction Y are both positively correlated with the value of W2. Therefore, increasing the value of W2 will improve the space utilization rate of the battery cell 20 in the first direction X within the housing 10, and decrease the space utilization rate of the battery cell 20 in the second direction Y within the housing 10. Conversely, decreasing the value of W2 will decrease the space utilization rate of the battery cell 20 in the first direction X within the housing 10, and improve the space utilization rate of the battery cell 20 in the second direction Y within the housing 10. In this embodiment, W2 / W1 is limited to between 2% and 7% to balance the space utilization rate of multiple battery cells 20 in the first direction X and the second direction Y within the housing cavity 13, thereby increasing the total capacity of multiple battery cells 20 in the housing cavity 13 and thus increasing the energy density of the battery device 100.

[0112] In some alternative embodiments, please refer to Figures 2 to 6 The dimension of the accommodating space 24 along the second direction Y is W3, and the dimension of the battery cell 20 along the second direction Y is W4: 2.3% ≤ 2W3 / W4 ≤ 6.5%.

[0113] It is understood that the battery cell 20 includes two receiving spaces 24. The ratio of the sum of the dimensions of the two receiving spaces 24 along the second direction Y to the dimension of the battery cell 20 along the second direction Y is the proportion of the space occupied by the tabs 222 in the battery cell 20. By limiting 2W3 / W4 to greater than or equal to 2.3%, the space dimension for arranging the tabs 222 is increased, thereby increasing the dimension of the battery cell 20 in the first direction X and increasing the space utilization rate of the battery cell 20 in the first direction X within the housing 10. By limiting 2W3 / W4 to less than or equal to 6.5%, the dimension of the battery cell 20 in the first direction X is controlled, increasing the number of battery cells 20 arranged in the first direction X within the housing 10 and reducing the number of battery cells 20 arranged in the second direction Y within the housing 10, thereby improving the space utilization rate of the battery cell 20 in the second direction Y within the housing 10.

[0114] For example, W3 / W4 can be 2.3%, 2.4%, 2.6%, 2.8%, 3%, 3.3%, 3.6%, 3.9%, 4.0%, 4.1%, 4.5%, 4.8%, 5.0%, 5.5%, 6.0%, or 6.5%.

[0115] Figure 7 This is a cross-sectional structural schematic diagram of another battery device provided in the embodiments of this application. Figure 8 This is a cross-sectional structural schematic diagram of another battery device provided in the embodiments of this application.

[0116] In some alternative embodiments, please refer to Figures 6 to 8 The number of battery cells 20 in the battery pack G is 2 to 4, that is, the battery pack G has two, three or four battery cells 20 arranged along the second direction Y, thereby reducing the impact of the accommodating space 24 on the battery device 100 in the second direction Y and improving the space utilization rate of the battery cells 20 in the housing 10 along the second direction Y.

[0117] In some alternative embodiments, please refer to Figures 3 to 6 The size of the cavity 13 along the first direction X is L1, and the size of the battery cell 20 along the first direction X is L2; ​​55≤L1 / L2≤90.

[0118] For example, the ratio of the size of the receiving cavity 13 along the first direction X to the size of the battery cell 20 along the first direction X is the number of battery cells 20 that can be arranged in the receiving cavity 13 along the first direction X. By limiting the number of arrangeable battery cells 20 to greater than or equal to 55, the number of battery cells 20 arranged in the second direction Y in the receiving cavity 13 is reduced, thereby improving the space utilization rate of battery cells 20 in the second direction Y in the housing 10. By limiting the number of arrangeable battery cells 20 to less than or equal to 90, the number of battery cells 20 arranged in the first direction X in the receiving cavity 13 is reduced, thereby improving the space utilization rate of battery cells 20 in the first direction X in the housing 10.

[0119] For example, L1 / L2 can be 55, 56, 58, 60, 65, 70, 75, 80, 85 or 90.

[0120] In some alternative embodiments, please refer to Figure 3 The outer shell 21 includes two first walls 211 arranged opposite each other along the first direction X and two second walls 212 arranged opposite each other along the second direction Y. Each first wall 211 is connected to the two second walls 212, thereby simplifying the production and assembly process of the outer shell 21, reducing the manufacturing cost, and the four walls are connected to each other to form a closed rigid frame, which can effectively disperse external impacts or pressures and reduce the possibility of local stress concentration.

[0121] The embodiments of this application do not limit the shape and size of the two first walls 211. The shape and size of the two first walls 211 can be the same or different.

[0122] The embodiments of this application do not limit the shape, size, or thickness of the two second walls 212. The shape, size, and thickness of the two second walls 212 can be the same or different.

[0123] Optionally, the area of ​​the first wall 211 and the area of ​​the second wall 212 can be the same or different. Optionally, the area of ​​the first wall 211 is smaller than the area of ​​the second wall 212.

[0124] Optionally, the two electrode terminals 23 are respectively disposed on the two second walls 212.

[0125] Optionally, the first wall 211 and the second wall 212 can be integrally formed, and the first wall 211 and the second wall 212 can also be connected by welding, riveting, bonding or other methods.

[0126] In some examples, the two first walls 211 and the two second walls 212 enclose a hollow cuboid structure.

[0127] Figure 9 This is a cross-sectional structural diagram of another battery cell provided in the embodiments of this application.

[0128] In some alternative embodiments, please refer to Figure 3 and Figure 9 The thickness of the first wall 211 is less than the thickness of the second wall 212.

[0129] It is understood that the first wall 211 is located in the thickness direction of the battery cell 20. During use, the battery cell 20 undergoes significant expansion deformation in the thickness direction. Through the above-mentioned arrangement in this embodiment, the first wall 211 is more likely to undergo elastic deformation, thereby absorbing some of the stress caused by volume changes, reducing the possibility of the outer casing 21 cracking or causing extrusion damage to the electrode assembly 22, and also reducing the amount of material used in the outer casing 21, thus reducing the overall weight of the battery cell 20. At the same time, the second wall 212 needs to be provided with electrode terminals 23. The second wall 212 can provide support for the electrode terminals 23, reducing the possibility of deformation or breakage of the electrode terminals 23 due to vibration, collision or internal expansion, and improving the reliability of the battery cell 20.

[0130] It should be noted that the thickness of the first wall 211 refers to the thickness between the outer surface of the first wall 211 and the inner surface of the first wall 211 facing the main body 221. The thickness of the second wall 212 refers to the thickness between the outer surface of the second wall 212 and the inner surface of the second wall 212 facing the main body 221. For example... Figure 9As shown, the thickness of the first wall 211 is d1, and the thickness of the second wall 212 is d2.

[0131] In some alternative embodiments, please refer to Figure 3 and Figure 9 The thickness of the first wall 211 is 0.3mm-0.8mm, and the thickness of the second wall 212 is 1.2mm-2.5mm.

[0132] For example, the thickness d1 of the first wall 211 can be 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm or 0.8mm.

[0133] For example, the thickness d2 of the second wall 212 can be 1.2mm, 1.3mm, 1.5mm, 1.7mm, 1.9mm, 2.0mm, 2.1mm, 2.3mm or 2.5mm.

[0134] In these alternative embodiments, the above-described configuration helps to reduce the overall weight of the battery cell 20, increase the mass energy density of the battery cell 20, and achieve a lightweight battery device 100.

[0135] In some alternative embodiments, please refer to Figures 3 to 6 The sum of the thicknesses of all the second walls 212 of the battery pack G is t1; 0.2% ≤ t1 / W1 ≤ 1%.

[0136] For example, each battery cell 20 includes two second walls 212. In the battery pack G, the sum of the thicknesses of the two second walls 212 of all battery cells 20 is t1. For example, when the thickness of all second walls 212 in the battery pack G is the same, the thickness of one second wall 212 is t, the battery pack G includes n battery cells 20, and t1 = 2 × n × t.

[0137] For example, the ratio of the sum of the thicknesses of all the second walls 212 of the battery pack G to the dimension of the receiving cavity 13 along the second direction Y can be 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or 1%.

[0138] In these alternative embodiments, the ratio of the sum of the thicknesses of all the second walls 212 of the battery pack G to the dimension of the receiving cavity 13 along the second direction Y is the space occupied by all the second walls 212 of the battery pack G in the second direction Y of the receiving cavity 13. With the above arrangement, it is beneficial to reduce the space occupied by the second walls 212 in the second direction Y of the receiving cavity 13, improve the energy density, and at the same time ensure the support capacity for the electrode terminals 23, reduce the possibility of deformation of the electrode terminals 23, and improve the reliability of the battery cell 20.

[0139] In some alternative embodiments, please refer to Figures 3 to 6 The number of battery packs G is m, the size of the cavity 13 along the first direction X is L1, and the thickness of the first wall 211 is t2; 1% ≤ 2 × m × t2 / L1 ≤ 3%.

[0140] For example, each battery cell 20 includes two first walls 211. The number of battery packs G arranged in the receiving cavity 13 in the first direction X can also be the number of battery cells 20 arranged along the first direction X. 2×m×t2 refers to the sum of the thicknesses of all the first walls 211 of a row of battery cells 20 in the first direction X.

[0141] For example, the ratio of the sum of the thicknesses of all the first walls 211 of the battery pack G to the dimension of the receiving cavity 13 along the first direction X can be 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.8%, 2.0%, 2.2%, 2.3%, 2.5%, 2.7%, 2.9%, or 3%.

[0142] In these alternative embodiments, the ratio of the sum of the thicknesses of all the first walls 211 of the battery pack G to the dimension of the receiving cavity 13 along the first direction X is the space occupied by all the first walls 211 of the battery pack G in the first direction X of the receiving cavity 13. With the above arrangement, it is beneficial to reduce the space occupied by the first walls 211 in the first direction X of the receiving cavity 13, improve the energy density, enhance the mechanical strength of the first walls 211, reduce the possibility of permanent deformation or cracking of the casing 21, and improve the reliability of the battery cell 20.

[0143] Figure 10 This is a cross-sectional structural diagram of another battery cell provided in the embodiments of this application.

[0144] In some alternative embodiments, please refer to Figures 3 to 10 The battery cell 20 also includes a pressure relief mechanism 25. The housing 21 includes a third wall 213 and a fourth wall 214 disposed opposite each other along the third direction Z. The pressure relief mechanism 25 is disposed on the third wall 213. The thickness of the third wall is greater than or equal to the thickness of the fourth wall 214.

[0145] The pressure relief mechanism 25 is used to release the internal gas of the battery cell 20.

[0146] As an example, the internal pressure or temperature of the battery cell 20 is actuated to release the internal pressure or temperature when it reaches a predetermined threshold. When the internal pressure or temperature of the battery cell 20 reaches the predetermined threshold, the pressure relief mechanism 25 is activated or a weak structure in the pressure relief mechanism is broken, thereby forming an opening or channel for the internal pressure or temperature to be released. The threshold design varies depending on the design requirements. The threshold may depend on the materials of one or more of the positive electrode, negative electrode, electrolyte, and separator in the battery cell 20.

[0147] As an example, the pressure relief mechanism 25 can be integrally formed with the housing 21.

[0148] As an example, the pressure relief mechanism 25 can also be separately configured and connected to the housing 21.

[0149] The term "actuation" as used in this application refers to the pressure relief mechanism 25 being activated or undergoing a certain state, thereby releasing the internal pressure and temperature of the battery cell 20. The actions of the pressure relief mechanism 25 may include, but are not limited to: movement of components within the pressure relief mechanism 25 to form an exhaust channel, rupture, breakage, tearing, or opening of at least a portion of the pressure relief mechanism 25, etc. When the pressure relief mechanism 25 is actuated, the high-temperature, high-pressure substances inside the battery cell 20 are discharged outwards from the actuated portion as waste. This method allows for pressure and temperature relief of the battery cell 20 under controllable pressure or temperature conditions, thereby preventing potentially more serious accidents.

[0150] In some embodiments, when the housing 21 is a non-sealed structure, the pressure relief mechanism 25 can be configured as a through hole for discharging gas inside the battery cell 20.

[0151] The emissions from the battery cell 20 mentioned in this application include, but are not limited to: electrolyte, dissolved or split positive and negative electrode plates, fragments of separators, high-temperature and high-pressure gases generated by the reaction, flames, etc.

[0152] Optionally, the pressure relief mechanism 25 can be located at the geometric center of the third wall 213, or it can be located at any position on the third wall 213.

[0153] It should be noted that the thickness of the third wall 213 refers to the thickness between the outer surface of the third wall 213 and the inner surface of the third wall facing the main body 221. The thickness of the fourth wall 214 refers to the thickness between the outer surface of the fourth wall 214 and the inner surface of the fourth wall facing the main body 221. For example... Figure 10 As shown, the thickness of the third wall 213 is d3, and the thickness of the fourth wall 214 is d4.

[0154] In some examples, the thickness of the third wall 213 is greater than that of the fourth wall 214, thereby increasing the mechanical strength of the third wall 213, reducing the possibility that the third wall 213 will deform during the actuation of the pressure relief mechanism 25, leading to deformation or even blockage of the exhaust passage, and improving the reliability of pressure relief. In other examples, the thickness of the third wall 213 is equal to the thickness of the fourth wall 214, so that the external pressure or internal expansion force is evenly transmitted on both shell walls, reducing the possibility of cracks or deformation caused by local stress concentration, improving the mechanical stability of the shell 21, and at the same time reducing production complexity and production costs.

[0155] In some alternative embodiments, please refer to Figure 3 and Figure 10 The thickness of the third wall 213 is 1.2mm-2.0mm, and the thickness of the fourth wall 214 is 0.3mm-0.8mm.

[0156] For example, the thickness d3 of the third wall 213 can be 1.2 mm, 1.3 mm, 1.4 mm, or...

[0157] 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm or 2.0mm.

[0158] For example, the thickness of the fourth wall d4 can be 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm or 0.8mm.

[0159] In these alternative embodiments, the above-described configuration helps to reduce the overall weight of the battery cell 20, increase the mass energy density of the battery cell 20, and achieve a lightweight battery device 100.

[0160] In some alternative embodiments, please refer to Figure 6 The dimension of the receiving cavity 13 along the first direction X is L1, where 1300mm≤L1≤2100mm and 1000mm≤W1≤1400mm.

[0161] For example, the dimensions of the receiving cavity 13 along the first direction X are 1300 mm, 1350 mm,

[0162] 1400mm, 1450mm, 1500mm, 1550mm, 1600mm, 1610mm, 1660mm,

[0163] 1700mm, 1800mm, 1900mm, 2000mm or 2100mm.

[0164] For example, the dimensions of the receiving cavity 13 along the second direction Y are 1000 mm, 1150 mm,

[0165] 1200mm, 1240mm, 1280mm, 1300mm, 13500mm, 1370mm, 1380mm, 1390mm or 1400mm.

[0166] In these alternative embodiments, the above-described configuration standardizes the size of the battery device 100, reduces development costs, improves production efficiency, optimizes space utilization by arranging the number of battery cells 20 as needed, and increases the energy density of the battery device 100.

[0167] In some alternative embodiments, please refer to Figure 3The outer casing 21 includes a housing 21a and two end caps 21b. The housing has an opening along a second direction Y. The two end caps 21b are respectively connected to the two ends of the housing 21a along the second direction Y and cover the opening. The end caps 21b are second walls 212, and the housing 21a includes a first wall 211.

[0168] The housing has an opening along the second direction Y. It can be understood that housing 21a is a hollow structure extending along the second direction Y, and housing 21a has two opening sides facing away from each other along the second direction Y. Two end caps 21b respectively cover the two opening sides.

[0169] Optionally, the two electrode terminals 23 are respectively disposed on two end caps 21b. As an example, the electrode terminals 23 and the end caps can be pre-assembled together and then assembled with the electrode assembly 22 and the housing 21a.

[0170] Compared to the housing, the end cap 21b typically has a greater thickness. Placing the electrode terminal 23 on the end cap 21b can improve the connection strength between the first electrode terminal 23 and the end cap 21b, enhance the stability of the electrode terminal 23, and reduce the risk of electrode terminal misalignment.

[0171] In some alternative embodiments, please refer to Figures 3 to 5 The outer casing 21 includes two second walls 212 disposed opposite each other along the second direction Y. The battery cell 20 also includes an insulating member 26 located on the side of the second wall 212 facing the main body 221. The insulating member 26 includes an insulating body 261 and a first protrusion 262, the first protrusion being disposed on the side of the insulating body 261 facing the main body 221. The distance between the surface of the main body facing the insulating body and the surface of the insulating body facing the main body 221 is greater than or equal to the dimension of the receiving space 24 along the second direction Y.

[0172] The insulating element 26 can be used for electrical insulation between the main body 221 and the second wall 212, thereby reducing the possibility of short circuit in the battery cell 20.

[0173] Optionally, the number of insulating members 26 includes two, with the two insulating members respectively disposed between the two second walls 212 and the main body 221.

[0174] The insulating element 26 includes an insulating body 261 and a first protrusion 262. The number of first protrusions may include two, with the two first protrusions 262 respectively disposed at two ends of the insulating body 261 along the third direction Z.

[0175] Optionally, the first protrusion 262 may be disposed in contact with the end face of the main body 221 facing the second wall 212, or the first protrusion 262 may be disposed at a distance from the end face of the main body 221 facing the second wall 212.

[0176] In these alternative embodiments, the above-described arrangement helps to reduce the possibility of interference between the connection structure between the tab 222 and the electrode terminal 23 and the insulating body 261, thereby improving the connection reliability between the tab 222 and the electrode terminal 23.

[0177] Figure 11 This is a cross-sectional structural schematic diagram of another battery device provided in the embodiments of this application.

[0178] In some alternative embodiments, please refer to Figure 11 The housing 10 also includes a beam structure 14, which is disposed in the receiving cavity 13 and divides the receiving cavity into multiple sub-cavities. The multiple sub-cavities are arranged sequentially along the first direction X, and each sub-cavity contains at least one battery pack G.

[0179] Optionally, the beam structure 14 may be provided to extend along the second direction Y.

[0180] Optionally, the beam structure 14 may be connected to the sidewall of the receiving cavity 13 in the second direction Y.

[0181] Optionally, the number of beam structures 14 may include one or more.

[0182] For example, multiple beam structures 14 can be spaced apart along a first direction X. Sub-cavities can also be formed between two adjacent beam structures 14.

[0183] In some examples, the sub-cavity can accommodate one or more battery packs G.

[0184] Optionally, the individual battery cells 20 within the battery pack in the sub-cavity can be connected in series or arranged in parallel. Of course, multiple individual battery cells 20 arranged along the first direction X within the sub-cavity can be connected in series or arranged in parallel.

[0185] In these alternative embodiments, during use, the battery cell 20 expands and deforms, especially in the first direction X, the expansion deformation is large, the beam structure 14 can deform, thereby absorbing some of the stress caused by the volume change, reducing the possibility of the battery cells 20 squeezing each other and causing rupture, and improving the reliability of the battery device 100.

[0186] Secondly, embodiments of this application provide an electrical device, including the battery device 100 in any of the foregoing embodiments, the battery device being used to provide electrical energy.

[0187] According to some embodiments of this application, please refer to Figures 2 to 11The battery device 100 includes a housing 10 and multiple battery packs G. The housing has a receiving cavity 13. The multiple battery packs are disposed in the receiving cavity and arranged along a first direction X. Each battery pack G includes multiple battery cells 20 arranged along a second direction Y. The first direction X is perpendicular to the second direction Y and parallel to the thickness direction of the battery cells 20. The dimension of the receiving cavity 13 along the first direction X is larger than the dimension of the receiving cavity along the second direction Y. The battery cell 20 includes a housing 21, an electrode assembly 22, and two electrode terminals 23. The two electrode terminals are respectively disposed at both ends of the housing 21 along the second direction Y. The electrode assembly 22 includes a main body 221 and two tabs 222. In the second direction Y, a receiving space 24 is provided between each electrode terminal 23 and the main body 221. The two tabs 222 are respectively led out from both ends of the main body 221 along the second direction Y. At least a portion of the tabs 222 is disposed in the receiving space 24 and electrically connected to the electrode terminals 23. The ratio of the sum of the dimensions of all the housing spaces 24 of the battery pack G along the second direction Y to the dimension of the housing cavity 13 along the second direction Y is 2%-7%.

[0188] The dimension of the accommodating space 24 along the second direction Y is W3, and the dimension of the battery cell 20 along the second direction Y is W4: 2.3% ≤ 2W3 / W4 ≤ 6.5. The number of battery cells 20 in the battery pack G is 2 or 3. The dimension of the accommodating cavity 13 along the first direction X is L1, and the dimension of the battery cell 20 along the first direction X is L2. 55 ≤ L1 / L2 ≤ 90. The sum of the thicknesses of all the second walls 212 of the battery pack G is t1. 0.2% ≤ t1 / W1 ≤ 1%. The number of battery packs G is m, the dimension of the accommodating cavity 13 along the first direction X is L1, and the thickness of the first wall 211 is t2. 1% ≤ 2 × m × t2 / L1 ≤ 3%.

[0189] The outer casing 21 includes two first walls 211 disposed opposite to each other along a first direction X and two second walls 212 disposed opposite to each other along a second direction Y, with each first wall 211 connecting to the two second walls 212. The thickness of the first wall is less than the thickness of the second wall.

[0190] The battery cell 20 also includes a pressure relief mechanism 25. The housing 21 includes a third wall 213 and a fourth wall 214 disposed opposite to each other along the third direction Z. The pressure relief mechanism 25 is disposed on the third wall 213. The thickness of the third wall is greater than or equal to the thickness of the fourth wall 214.

[0191] The outer casing 21 includes a housing 21a and two end caps 21b. The housing has an opening along a second direction Y, and the two end caps 21b are respectively connected to the two ends of the housing 21a along the second direction Y and cover the opening. The end caps 21b are second walls 212, and the housing 21a includes a first wall 211.

[0192] The housing 10 also includes a beam structure 14, which is disposed in the receiving cavity 13 and divides the receiving cavity into multiple sub-cavities. The multiple sub-cavities are arranged sequentially along the first direction X, and each sub-cavity contains at least one battery pack G.

[0193] Example

[0194] The following embodiments describe the contents disclosed in this application in more detail. These embodiments are merely illustrative, as various modifications and variations will be apparent to those skilled in the art within the scope of the disclosure of the embodiments of this application. Unless otherwise stated, all parts, percentages, and ratios reported in the following embodiments are based on mass, and all reagents used in the embodiments are commercially available or synthesized by conventional methods and can be used directly without further processing, and the instruments used in the embodiments are commercially available.

[0195] Example 1

[0196] 1. Preparation of positive electrode sheet

[0197] The positive electrode includes a positive current collector and a positive film layer disposed on both sides of the positive current collector. The positive current collector is an aluminum foil with a thickness of 15μm.

[0198] The positive electrode film layer comprises a film layer formed by uniformly coating a positive electrode slurry (solvent being N-methylpyrrolidone NMP) onto the surface of a positive electrode conductive layer, followed by drying and cold pressing. The positive electrode film layer comprises a positive electrode active material (lithium iron phosphate), a binder polyvinylidene fluoride (PVDF), and a conductive agent acetylene black in a weight ratio of 97:2:1.

[0199] 2. Preparation of negative electrode sheet

[0200] The negative electrode sheet includes a negative current collector and a negative electrode film layer disposed on both sides of the negative current collector. The negative current collector is a copper foil with a thickness of 6μm.

[0201] The negative electrode film layer comprises a film layer formed by uniformly coating a negative electrode slurry (with deionized water as the solvent) onto the surface of a negative electrode conductive layer, followed by drying and cold pressing.

[0202] The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is located on both sides of the negative electrode current collector. The negative electrode current collector is a copper foil. The negative electrode active material layer is a film layer formed by uniformly coating the surface of the negative electrode current collector copper foil with negative electrode slurry (solvent is deionized water), and then drying and cold pressing. The negative electrode active material layer includes graphite, conductive agent Super-p, and binder styrene-butadiene rubber (SBR) in a weight ratio of 97:2:1.

[0203] 3. Separating membrane

[0204] A 7μm polyethylene film.

[0205] 4. Preparation of electrolyte

[0206] The electrolyte consists of organic solvents, lithium salts, and additives.

[0207] The electrolyte consists of an organic solvent and a lithium salt. Ethyl carbonate (EC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC) are mixed in a volume ratio of 1:1:1 to obtain an organic solvent. Then, fully dried lithium salt LiPF6 is dissolved in the mixed organic solvent to prepare an electrolyte with a lithium salt concentration of 1 mol / L.

[0208] 5. Preparation of battery cells

[0209] The positive electrode, separator, and negative electrode are stacked in sequence, with the separator positioned between the positive and negative electrodes to provide isolation, thus obtaining an electrode assembly. The electrode assembly is placed in a housing, dried, and then injected with electrolyte. After vacuum sealing, settling, formation, and shaping, a single battery cell is obtained.

[0210] The thickness (dimension along the first direction) of the battery cell is 31.3 mm, the width (dimension along the second direction) is 288.3 mm, and the height (dimension along the third direction) is 111 mm. The sum of the dimensions of the two accommodating spaces of the battery cell along the second direction is 14 mm.

[0211] 6. Battery manufacturing

[0212] The 192 prepared battery cells were installed into the casing, and then the busbar components were welded and the high and low voltage wiring harnesses were installed to obtain the battery.

[0213] The housing cavity of the casing has a dimension of 1660mm along the first direction, a dimension of 1240mm along the second direction, and a dimension of 135mm along the third direction. Three battery cells are arranged within the casing along the second direction.

[0214] Example 2

[0215] Battery cells and batteries were prepared using a method similar to that of Example 1. The difference from Example 1 is that the thickness, width, and dimensions of the housing space of the battery cells, as well as the number of battery cells arranged along the second direction inside the housing, were adjusted. Specific dimensions are shown in Table 1.

[0216] Example 3

[0217] Battery cells and batteries were prepared using a method similar to that of Example 1. The difference from Example 1 is that the thickness, width, and dimensions of the housing space of the battery cells, as well as the number of battery cells arranged along the second direction inside the housing, were adjusted. Specific dimensions are shown in Table 1.

[0218] Comparative Example 1

[0219] Battery cells and batteries were prepared using a method similar to that of Example 1. The difference from Example 1 is that the thickness, width, and dimensions of the housing space of the battery cells, as well as the number of battery cells arranged along the second direction inside the housing, were adjusted. Specific dimensions are shown in Table 1.

[0220] Comparative Example 2

[0221] Battery cells and batteries were prepared using a method similar to that of Example 1. The difference from Example 1 is that the thickness, width, and dimensions of the housing space of the battery cells, as well as the number of battery cells arranged along the second direction inside the housing, were adjusted. Specific dimensions are shown in Table 1.

[0222] test

[0223] 1. Test the total capacity of the battery device.

[0224] At 25°C, the battery device is charged at a constant current of 0.33C until the voltage of a single battery cell reaches 3.8V, and then charged at a constant voltage until the current is 0.05C. After the battery device is left to stand for 30 minutes, it is discharged at a constant current of 0.33C until the voltage of a single battery cell reaches 2.08V. The discharge amount at this time is recorded as the total capacity of the battery device.

[0225] 2. The ratio of the sum of the dimensions of all the accommodating spaces arranged along the second direction in the battery device, W2, to the dimension of the accommodating cavity along the second direction, W1.

[0226] The test results of Examples 1-3 and Comparative Examples 1-2 are shown in Table 1.

[0227]

[0228] Table 1 shows that the total capacity of the battery device can be improved by adjusting the W2 / W1 ratio. However, Comparative Example 1 shows that when the W2 / W1 ratio is too small, the space utilization rate of the battery cells in the first direction of the housing decreases, resulting in a decrease in the total number of battery devices. Comparative Example 2 shows that when the W2 / W1 ratio is too large, the space utilization rate of the battery cells in the second direction of the housing decreases, resulting in a decrease in the total number of battery devices. Examples 1 to 3, by adjusting the W2 / W1 ratio to a suitable range, such as 2% ≤ W2 / W1 ≤ 7%, can significantly improve the total capacity of the battery device, thereby increasing the energy density of the battery device.

[0229] 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 device, characterized in that, include: The box-shaped enclosure has a receiving cavity; Multiple battery packs are disposed in the receiving cavity and arranged along a first direction. Each battery pack includes multiple battery cells arranged along a second direction. The first direction is perpendicular to the second direction and parallel to the thickness direction of the battery cells. Wherein, the dimension of the receiving cavity along the first direction is larger than the dimension of the receiving cavity along the second direction; The battery cell includes a casing, an electrode assembly, and two electrode terminals. The two electrode terminals are respectively disposed at both ends of the casing along the second direction. The electrode assembly includes a main body and two tabs. In the second direction, there is a receiving space between each electrode terminal and the main body. The two tabs are respectively led out from both ends of the main body along the second direction. At least a portion of the tabs is disposed in the receiving space and electrically connected to the electrode terminals. The ratio of the sum of the dimensions of all the housing spaces of the battery pack along the second direction to the dimension of the housing cavity along the second direction is 2%-7%.

2. The battery device according to claim 1, characterized in that, The dimension of the accommodating space along the second direction is W3, and the dimension of the battery cell along the second direction is W4. 2.3% ≤ 2W3 / W4 ≤ 6.

5.

3. The battery device according to claim 1 or 2, characterized in that, The number of individual battery cells in the battery pack is 2 to 4.

4. The battery device according to any one of claims 1-3, characterized in that, The dimension of the receiving cavity along the first direction is L1, and the dimension of the battery cell along the first direction is L2; 55≤L1 / L2≤90.

5. The battery device according to any one of claims 1-4, characterized in that, The outer casing includes two first walls disposed opposite each other along the first direction and two second walls disposed opposite each other along the second direction, with each first wall connecting to the two second walls.

6. The battery device according to claim 5, characterized in that, The thickness of the first wall is less than the thickness of the second wall.

7. The battery device according to claim 6, characterized in that, The thickness of the first wall is 0.3mm-0.8mm, and the thickness of the second wall is 1.2mm-2.5mm.

8. The battery device according to any one of claims 5-7, characterized in that, The sum of the thicknesses of all the second walls of the battery pack is t1; 0.2% ≤ t1 / W1 ≤ 1%.

9. The battery device according to any one of claims 5-8, characterized in that, The number of battery packs is m, the dimension of the receiving cavity along the first direction is L1, and the thickness of the first wall is t2; 1% ≤ 2 × m × t² / L₁ ≤ 3%.

10. The battery device according to any one of claims 1-9, characterized in that, The battery cell also includes a pressure relief mechanism. The housing includes a third wall and a fourth wall disposed opposite to each other along a third direction. The pressure relief mechanism is disposed on the third wall. The thickness of the third wall is greater than or equal to the thickness of the fourth wall.

11. The battery device according to claim 10, characterized in that, The thickness of the third wall is 1.2mm-2.0mm, and the thickness of the fourth wall is 0.3mm-0.8mm.

12. The battery device according to any one of claims 1-11, characterized in that, The dimension of the receiving cavity along the first direction is L1, 1300mm≤L1≤2100mm; 1000mm≤W1≤1400mm.

13. The battery device according to any one of claims 5-12, characterized in that, The outer casing includes a housing and two end caps. The housing has an opening along the second direction, and the two end caps are respectively connected to both ends of the housing along the second direction and cover the opening. The end cap is the second wall, and the housing includes the first wall.

14. The battery device according to any one of claims 1-13, characterized in that, The outer casing includes two second walls disposed opposite to each other along the second direction; The battery cell also includes an insulating component, which is located on the side of the second wall facing the main body. The insulating component includes an insulating body and a first protrusion, which is provided to protrude from the insulating body on the side of the insulating body facing the main body. The distance between the surface of the main body facing the insulating body and the surface of the insulating body facing the main body is greater than or equal to the dimension of the accommodating space along the second direction.

15. The battery device according to any one of claims 1-14, characterized in that, The housing also includes a beam structure, which is disposed in the receiving cavity and divides the receiving cavity into multiple sub-cavities. The multiple sub-cavities are arranged sequentially along the first direction, and each sub-cavity contains at least one of the battery packs.

16. An electrical appliance, characterized in that, Includes the battery device as described in any one of claims 1 to 15, the battery device being used to provide electrical energy.

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