Battery device and electric device

Abstract

The utility model relates to the technical field of batteries and discloses a battery device and a power utilization device.The battery device comprises a battery pack, the battery pack comprises a first shell, a second shell and a plurality of soft package battery monomers, the first shell and the second shell are sequentially arranged in the first direction and connected, and the first shell is provided with a first U-shaped mounting cavity; the first shell is provided with a first U-shaped mounting cavity, the second shell is provided with a second U-shaped mounting cavity, the first U-shaped mounting cavity and the second U-shaped mounting cavity are each internally provided with a plurality of soft package battery monomers, the first U-shaped mounting cavity and the second U-shaped mounting cavity are used for limiting movement of the soft package battery monomers in the first U-shaped mounting cavity and the second U-shaped mounting cavity from two opposite directions in a second direction, and the second direction is perpendicular to the first direction. Therefore, the structural strength of the battery pack and the resistance to impact in the second direction can be enhanced, so that the use reliability of the battery device is improved.

Description

Technical Field

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

[0002] In recent years, new energy vehicles have developed by leaps and bounds. As the power source of electric vehicles, battery devices play an irreplaceable and important role. Among them, battery devices use battery cells to store and provide electrical energy. Among them, soft-pack battery cells have been widely used due to their unique structure and advantages.

[0003] However, in the related art, the reliability of the battery device having the soft-pack battery cells needs to be further improved. Utility Model Content

[0004] The embodiments of the present application provide a battery device and an electrical device, which can enhance the structural strength of a battery pack and its ability to resist impact in a second direction, thereby improving the reliability of the battery device.

[0005] In a first aspect, an embodiment of the present application provides a battery device, comprising: a battery pack, comprising a first shell, a second shell and a plurality of soft-pack battery cells, the first shell and the second shell are arranged in sequence along a first direction and are connected, the first shell has a first U-shaped mounting cavity, the second shell has a second U-shaped mounting cavity, a plurality of soft-pack battery cells are respectively arranged in the first U-shaped mounting cavity and the second U-shaped mounting cavity, and are used to limit the movement of the soft-pack battery cells therein from two opposite directions in a second direction, and the second direction is perpendicular to the first direction.

[0006] In the above technical solution, the first shell and the second shell can respectively play a certain role in protecting and supporting the soft-pack battery cells therein; and the first shell and the second shell are connected to each other, so as to realize the connection between the module composed of the first shell and the multiple soft-pack battery cells therein and the module composed of the second shell and the multiple soft-pack battery cells therein, so as to facilitate the battery pack to be better connected as an integral structure, facilitate the assembly of the battery pack itself and can be installed as a whole, and at the same time, it is beneficial to enhance the structural strength of the battery pack, and improve the main frequency of the battery pack, that is, to improve the overall vibration frequency of the battery pack, and improve the mechanical properties of the battery pack, thereby improving the reliability of the battery device; in addition, the first U-shaped mounting cavity and the second U-shaped mounting cavity are used to limit the movement of the soft-pack battery cells therein from two opposite directions in the second direction, so that the first shell and the second shell can be used to resist the impact from the two opposite directions in the second direction, respectively, and the battery pack can withstand the impact from the two opposite directions in the second direction, which is beneficial to improve the balance of the entire battery pack in resisting the impact of the two opposite directions in the second direction, and improve the resistance of the battery pack to the impact in the second direction, thereby improving the reliability of the battery pack.

[0007] In some embodiments, a portion of the first shell connected to the second shell extends into the second U-shaped mounting cavity, and a portion of the second shell connected to the first shell extends into the first U-shaped mounting cavity.

[0008] In the above technical solution, by arranging the part of the first shell extending into the second U-shaped mounting cavity to be connected with the part of the second shell extending into the first U-shaped mounting cavity, the connection between the first shell and the second shell can not only limit the separation of the first shell and the second shell through the connection position of the two, but the first shell and the second shell themselves can limit the separation of the two, thereby improving the connection strength between the first shell and the second shell and improving the connection reliability of the first shell and the second shell.

[0009] In some embodiments, a reinforcement protrusion is provided on the outer surface of at least one of the first shell and the second shell.

[0010] In the above technical solution, by protruding a reinforcing protrusion on the outer surface of at least one of the first shell and the second shell, the structural strength of the above at least one of the first shell and the second shell can be improved. At the same time, the arrangement of the reinforcing protrusion will not occupy the arrangement space provided by the above at least one of the first shell and the second shell for the soft-pack battery cell, nor will it affect the flatness of the inner surface of the above at least one of the first shell and the second shell, so that the inner surface of the first shell and the inner surface of the second shell can still provide a relatively flat limiting surface for the soft-pack battery therein, so that the reinforcing protrusion is not easy to excessively squeeze the soft-pack battery cell and cause lithium plating problems.

[0011] In some embodiments, the battery device further includes: an elastic pad, the elastic pad being sandwiched between the first shell and the second shell.

[0012] In the above technical solution, an elastic pad is sandwiched between the first shell and the second shell to reserve a certain space for the deformation of the first shell and the second shell. At the same time, the elastic pad can absorb the deformation of the first shell and the second shell. It is not easy for a large extrusion force to be generated between the first shell and the second shell due to deformation, which is beneficial to reducing the extrusion force generated by the deformation of the first shell and the second shell on the soft-pack battery monomer and reducing the risk of lithium plating in the soft-pack battery monomer.

[0013] In some embodiments, the resilient pad is a thermal insulator.

[0014] In the above technical solution, by setting the elastic pad as a thermal insulation component, the heat transfer between the first shell and the second shell can be reduced, so that the elastic pad can not only prolong the heat transfer time between the first shell and the second shell, and delay the occurrence speed of thermal runaway of adjacent modules, but also reduce the risk of thermal runaway of adjacent modules, thereby helping to improve the thermal stability and reliability of the battery device.

[0015] In some embodiments, the first shell includes a first shell wall, a second shell wall and a third shell wall, the first shell wall and the second shell wall are spaced apart along the first direction, the third shell wall is connected to one end of the first shell wall and the second shell wall in the second direction to close one end of the first U-shaped mounting cavity in the second direction and to limit the movement of the internal soft-pack battery cell, the second shell includes a fourth shell wall, a fifth shell wall and a sixth shell wall, the fourth shell wall is adjacent to and fixedly connected to the second shell wall, and the fourth shell wall and the fifth shell wall are spaced apart along the first direction, the sixth shell wall is connected to the other end of the fourth shell wall and the fifth shell wall in the second direction to close one end of the second U-shaped mounting cavity in the second direction and to limit the movement of the internal soft-pack battery cell.

[0016] In the above technical solution, the second shell wall and the fourth shell wall are located between the first shell wall and the fifth shell wall, the first shell wall, the second shell wall and the third shell wall define a first U-shaped installation cavity, all of which are the cavity walls of the first U-shaped installation cavity, and the fourth shell wall, the fifth shell wall and the sixth shell wall define a second U-shaped installation cavity, all of which are the cavity walls of the second U-shaped installation cavity. The structure of the first shell wall and the second shell is simple and convenient to process, and it is convenient to connect the first shell and the second shell.

[0017] In some embodiments, the fourth shell wall is located on a side of the second shell wall facing away from the first shell wall; or, the fourth shell wall is located on a side of the second shell wall facing the first shell wall.

[0018] In the above technical solution, by setting the fourth shell wall to be located on the side of the second shell wall facing the first shell wall, and the fourth shell wall is fixedly connected to the second shell wall, the connection between the first shell and the second shell is achieved. At this time, the first shell and the second shell are cross-connected, which can not only limit the separation of the first shell and the second shell through the connection position between the two, but the second shell wall itself can limit the fourth shell wall away from the first shell, and the fourth shell wall itself can limit the second shell wall away from the second shell, so that the first shell and the second shell themselves can limit the separation of the two, thereby improving the connection strength between the first shell and the second shell, and improving the connection reliability between the first shell and the second shell; by setting the fourth shell wall, it can also be located on the side of the second shell wall away from the first shell wall, and the connection between the second shell wall and the fourth shell wall can also be achieved, and the height dimension of the second shell wall is not easily restricted by the second U-shaped installation cavity, and the height dimension of the fourth shell wall is not easily restricted by the first U-shaped installation cavity, and the structure is more flexible.

[0019] In some embodiments, the fourth shell wall is located on the side of the second shell wall facing the first shell wall, the free end of the second shell wall stops at the connection position between the fourth shell wall and the sixth shell wall, and the free end of the fourth shell wall stops at the connection position between the second shell wall and the third shell wall.

[0020] In the above technical solution, by setting the free end of the second shell wall to stop at the connection position between the fourth shell wall and the sixth shell wall, the free end of the fourth shell wall stops at the connection position between the second shell wall and the third shell wall, which facilitates the positioning of the first shell and the second shell in the second direction during the assembly process, facilitates the subsequent fixation of the first shell and the second shell, and is beneficial to improving the assembly convenience and assembly efficiency of the battery pack.

[0021] In some embodiments, each of the first shell wall, the second shell wall, the fourth shell wall and the fifth shell wall is configured to include a first plate portion and a second plate portion arranged and connected along a second direction, the second plate portion and the pole ear of the soft-pack battery cell are staggered in the second direction, the first plate portion and the pole ear are opposite to each other along the first direction, and in the third direction, the length of the first plate portion is greater than the length of the second plate portion, and the pole ear extends between one end of the length of the first plate portion and one end of the length of the second plate portion.

[0022] In the above technical solution, by setting the first plate portion and the second plate portion, the first plate portion can play a certain protective role on the pole ear, so that when the battery pack is assembled with other components such as a busbar, the pole ear is not easy to interfere with other components, which can reduce the probability of scratching the pole ear by other components. At the same time, the amount of material used for the first shell and the second shell is relatively small, which is conducive to reducing material costs.

[0023] In some embodiments, at least one outer surface of the first shell wall, the third shell wall, the fifth shell wall and the sixth shell wall is provided with a reinforcing protrusion; and / or at least one of the side surfaces opposite to each other of the second shell wall and the fourth shell wall is provided with a reinforcing protrusion.

[0024] In the above technical solution, the setting of the reinforcing protrusion can improve the structural strength of at least one of the first shell and the second shell, and at the same time will not occupy the arrangement space provided by at least one of the first shell and the second shell for the soft-pack battery cell, nor will it affect the flatness of the inner surface of at least one of the first shell and the second shell, so that the inner surface of the first shell and the inner surface of the second shell can still provide a relatively flat limiting surface for the soft-pack battery therein, so that the reinforcing protrusion is not easy to excessively squeeze the soft-pack battery cell and cause lithium plating problems.

[0025] In some embodiments, the reinforcing protrusions are configured as ribs or dots.

[0026] In the above technical solution, the structure of the reinforcing protrusion is simple and easy to process.

[0027] In some embodiments, the first shell and the second shell are an integral piece or separate pieces.

[0028] In the above technical solution, the first shell and the second shell are set as separate parts, and the two are fixedly connected by assembly means, allowing the first shell and the second shell to be more flexibly adjusted during the assembly process, so as to adapt to different installation environments. In particular, when there are differences in the number and size of soft-pack battery cells, the split design structure can more easily adapt to these changes so that the battery pack can be installed correctly and stably; the first shell and the second shell can also be an integral part, which can save the connection process between the first shell and the second shell, and is conducive to improving the assembly efficiency of the battery pack.

[0029] In some embodiments, there are a plurality of first shells and a plurality of second shells, respectively, and the plurality of first shells and the plurality of second shells are alternately arranged one by one along the first direction.

[0030] In the above technical solution, by arranging multiple first shells and multiple second shells alternately along the first direction, the regular arrangement of the first shells and the second shells in the battery pack is facilitated, which is beneficial to further enhance the ability of the entire battery pack to resist impact in the second direction, and is beneficial to enhance the balancing ability of the entire battery pack to resist impact in the opposite direction in the second direction.

[0031] In some embodiments, the battery device also includes: a box body having a accommodating cavity, the battery pack is arranged in the accommodating cavity, the closed end of the first U-shaped mounting cavity in the second direction is fixedly connected to the box body, and the closed end of the second U-shaped mounting cavity in the second direction is fixedly connected to the box body; and / or, the battery device also includes a first connecting plate and a second connecting plate, the first connecting plate closes the open end of the first U-shaped mounting cavity in the second direction, the second connecting plate closes the open end of the second U-shaped mounting cavity in the second direction, the first shell is fixedly connected to the box body through the first connecting plate, and the second shell is fixedly connected to the box body through the second connecting plate.

[0032] In the above technical solution, by setting the closed end of the first U-shaped mounting cavity in the second direction to be fixedly connected to the box body, and the closed end of the second U-shaped mounting cavity in the second direction to be fixedly connected to the box body, it is beneficial to increase the connection area between the first shell and the box body, and improve the connection strength and connection reliability of the first shell and the box body. It is also beneficial to increase the connection area between the second shell and the box body, and improve the connection strength and connection reliability of the second shell and the box body. By setting the first connecting plate and the second connecting plate, the limiting reliability of the soft-pack battery cell in the second direction can be improved, and at the same time, an intermediate transition can be provided for the connection between the first shell and the second shell and the box body, which facilitates the connection between the first shell, the second shell and the box body.

[0033] In some embodiments, the battery device also includes at least one of a first heat exchange element and a second heat exchange element, at least one of the first heat exchange element and the second heat exchange element is used for heat exchange with the soft-pack battery cell, the first heat exchange element is arranged between the first shell and the second shell, and the second heat exchange element is arranged between the battery pack and the box.

[0034] In the above technical solution, by providing at least one of the first heat exchange element and the second heat exchange element, it is convenient to implement thermal management of the soft-pack battery cell, which is beneficial to improving the working efficiency and stability of the battery device.

[0035] In some embodiments, the soft-pack battery cell is any one of a lithium iron phosphate battery cell, a ternary battery cell, and a solid-state battery cell. In the above technical solution, the use of the above types of soft-pack battery cells can provide more options for the design of the battery device to meet different usage requirements. Among them, the soft-pack battery cell is a lithium iron phosphate battery cell, which has the advantages of high reliability, long cycle life, light weight, large capacity, and low internal resistance; the soft-pack battery cell is a ternary battery cell, which has the advantages of high energy density and good electrochemical performance; the soft-pack battery cell is a solid-state battery cell, which has the advantages of high energy density and high reliability, light weight, and good high and low temperature performance.

[0036] In some embodiments, the soft-pack battery cell is a lithium iron phosphate battery cell, and in the positive electrode material of the soft-pack battery cell, the usage ratio of the positive electrode active material, the binder, and the conductive agent is 96: (1-3): (1-3); the soft-pack battery cell is a ternary battery cell, and in the positive electrode material of the soft-pack battery cell, the usage ratio of the positive electrode active material, the binder, and the conductive agent is 96: (2-3): (1-2).

[0037] In the above technical solution, when the soft-pack battery cell is a lithium iron phosphate battery cell, a high proportion of positive electrode active materials means that more substances capable of electrochemical reactions can be accommodated in a limited electrode assembly, which is beneficial to increasing the capacity and energy density of the battery device, so that the lithium iron phosphate battery cell can output a higher amount of electricity while being relatively small in volume and weight, meeting the application scenarios with certain requirements for energy density. The use of the above range of binder and conductive agent can reduce the cost of auxiliary materials, thereby reducing the overall cost of the battery device. When the soft-pack battery cell is a ternary battery cell, since the structure and surface properties of the ternary material itself are relatively complex, the use of the above-mentioned proportion of positive electrode active materials, binders, and conductive agents is beneficial to ensuring good bonding between the positive electrode active material particles and between the active material and the current collector, thereby improving the mechanical stability and integrity of the electrode assembly, and is beneficial to reducing the risk of active material shedding and electrode pulverization during charging and discharging, and extending the cycle life of the battery device.

[0038] In some embodiments, the soft-pack battery cell is a ternary battery cell, and the shell walls of the first shell and the second shell for limiting the movement of the soft-pack battery cells therein in opposite directions in the second direction are respectively provided with pressure relief portions.

[0039] In the above technical solution, when the ternary battery cell undergoes thermal runaway expansion and exhaust pressure relief, the pressure relief unit can guide the exhausted gas to directional pressure relief, thereby reducing the risk of gas chaos affecting the surrounding ternary battery cells, and also reducing the risk of severe thermal runaway of the battery pack composed of the ternary battery cells, which is beneficial to the thermal runaway management of the battery pack and improves the reliability of the battery pack composed of the ternary battery cells.

[0040] In some embodiments, the pressure relief portion is configured as a pressure relief hole; or, the pressure relief portion is configured as a notch; or, the pressure relief portion is configured as a weakened portion. In the above technical solution, more options can be provided for the design of the pressure relief portion to meet different usage requirements.

[0041] In a second aspect, an embodiment of the present application provides an electrical device, comprising the battery device of any of the above embodiments.

[0042] In the above technical solution, since the battery device has high reliability, the use of the battery device can improve the power consumption reliability of the power-consuming device. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0044] Figure 1 A schematic diagram of a structure in which the electric device provided in some embodiments of the present application is a vehicle;

[0045] Figure 2 An exploded view of the structure of a battery device provided in some embodiments of the present application;

[0046] Figure 3 An exploded view of the structure of a battery device provided in another embodiment of the present application;

[0047] Figure 4 A schematic diagram of a battery pack provided for some embodiments of the present application;

[0048] Figure 5 for Figure 4 A schematic diagram of the first shell and the second shell shown in ;

[0049] Figure 6 for Figure 4 Another schematic diagram of the battery pack shown in;

[0050] Figure 7 for Figure 4Another schematic diagram of the battery pack shown in;

[0051] Figure 8 for Figure 4 Another schematic diagram of the battery pack shown in;

[0052] Fig. 9 A partial schematic diagram of a box provided in some embodiments of the present application;

[0053] Fig.10 for Fig. 9 Another schematic diagram of the box shown;

[0054] Fig.11 for Fig. 9 Another schematic diagram of the box shown.

[0055] Reference numerals:

[0056] Power device 1000, battery device 100, controller 200, motor 300,

[0057] Box body 1, accommodating cavity 1a, first box body 11, second box body 12, top plate 13, bottom plate 14, battery pack 2, pressure relief part 20, first shell 21, first U-shaped mounting cavity 21a, first limiting shell wall 21b, first shell wall 211, second shell wall 212, third shell wall 213, second shell 22, second U-shaped mounting cavity 22a, second limiting shell wall 22b, fourth shell wall 221, fifth shell wall 222, sixth shell wall 223, soft-pack battery cell 23, pole ear 231, battery cell 23A, first plate portion 31, second plate portion 32. DETAILED DESCRIPTION

[0058] 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.

[0059] 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] 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 the various components in the embodiments of the present application shown in the drawings are only exemplary and should not constitute any limitation on the present application. The "multiple" appearing in the present application refers to more than two (including two).

[0064] In the present application, the battery cells may include lithium ion batteries, sodium ion batteries, sodium lithium ion batteries, lithium metal batteries, sodium metal batteries, lithium sulfur batteries, magnesium ion batteries, nickel metal hydride batteries, nickel cadmium batteries, lead storage batteries, etc., which are not limited in the embodiments of the present application. The battery cells may be cylindrical, flat, rectangular or other shapes, which are not limited in the embodiments of the present application.

[0065] The battery apparatus (Battery Apparatus) mentioned in the embodiments of the present application may refer to one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly (Battery Cell Assembly) may include multiple battery cells, and the multiple battery cells are connected in series, in parallel, or in mixed connection through a busbar. In some embodiments, the battery cell assembly (Battery Cell Assembly) is generally formed by arranging multiple battery cells.

[0066] As an example, the battery cell assembly may be a battery module, where a plurality of battery cells are arranged and fixed 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.

[0067] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more battery cell assemblies, and the battery cell assemblies are accommodated in the housing. As an example, the battery cell assembly may be a battery pack, and the battery cell assembly may be accommodated in the housing by fixing the battery pack in the housing. As an example, the battery cell assembly may also be accommodated in the housing by directly fixing a plurality of battery cells to the housing. The housing may prevent liquid or other foreign matter from affecting the charging or discharging of the battery cells.

[0068] The battery cell includes a shell, an electrode assembly and an electrolyte. The shell is used to accommodate the electrode assembly and the electrolyte. In the present application, a soft-pack battery cell may refer to a battery cell using a soft outer packaging material as a shell. The electrode assembly is composed of a positive electrode sheet, a negative electrode sheet and a separator. The battery cell mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive electrode collector and a positive electrode active material layer. The positive electrode active material layer is coated on the surface of the positive electrode collector. The positive electrode collector not coated with the positive electrode active material layer protrudes from the positive electrode collector coated with the positive electrode active material layer. The positive electrode collector not coated with the positive electrode active material layer serves as a positive electrode ear. Taking lithium-ion batteries as an example, the material of the positive electrode collector may be aluminum, and the positive electrode active material may be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide, etc. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode current collector. The negative electrode current collector not coated with the negative electrode active material layer protrudes from the negative electrode current collector coated with the negative electrode active material layer. The negative electrode current collector not coated with the negative electrode active material layer serves as a negative electrode tab. The material of the negative electrode current collector can be copper, and the negative electrode active material can be carbon or silicon, etc. In order to ensure that a large current passes without melting, the number of positive electrode tabs is multiple and stacked together, and the number of negative electrode tabs is multiple and stacked together.

[0069] The material of the isolation film may be PP (polypropylene) or PE (polyethylene), etc. In addition, the electrode assembly may be a winding structure or a stacked structure, but the embodiments of the present application are not limited thereto.

[0070] In recent years, new energy vehicles have developed by leaps and bounds, and battery devices, as the power source of electric vehicles, play an irreplaceable and important role. Among them, battery devices use battery cells to store and provide electrical energy, and among the many types of battery cells, soft-pack battery cells have been widely used due to their unique structure and advantages.

[0071] For example, the soft-pack battery cell uses an aluminum-plastic film to wrap the electrode assembly and electrolyte. The aluminum-plastic film is light in weight and can significantly reduce the weight of the battery device and increase the energy density of the battery device. However, in the related art, when using soft-pack battery cells, the soft-pack battery cells in the box are prone to deformation due to their low structural strength and insufficient resistance to external impact.

[0072] Based on the above considerations, a battery device is proposed, which includes a battery pack, the battery pack includes a first shell, a second shell and a plurality of soft-pack battery cells, the first shell and the second shell are arranged in sequence along a first direction and are connected, the first shell has a first U-shaped mounting cavity, the second shell has a second U-shaped mounting cavity, and the first U-shaped mounting cavity and the second U-shaped mounting cavity are respectively provided with a plurality of soft-pack battery cells, and are used to limit the movement of the soft-pack battery cells therein from two opposite directions in a second direction, and the second direction is perpendicular to the first direction.

[0073] In the above technical solution, the first shell and the second shell can respectively play a certain role in protecting and supporting the soft-pack battery cells therein; and the first shell and the second shell are connected to each other, so as to realize the connection between the module composed of the first shell and the multiple soft-pack battery cells therein and the module composed of the second shell and the multiple soft-pack battery cells therein, so as to facilitate the battery pack to be better connected as an integral structure, facilitate the assembly of the battery pack itself and can be installed as a whole, and at the same time, it is beneficial to enhance the structural strength of the battery pack, and improve the main frequency of the battery pack, that is, to improve the overall vibration frequency of the battery pack, and improve the mechanical properties of the battery pack, thereby improving the reliability of the battery device; in addition, the first U-shaped mounting cavity and the second U-shaped mounting cavity are used to limit the movement of the soft-pack battery cells therein from two opposite directions in the second direction, so that the first shell and the second shell can be used to resist the impact from the two opposite directions in the second direction, respectively, and the battery pack can withstand the impact from the two opposite directions in the second direction, which is beneficial to improve the balance of the entire battery pack in resisting the impact of the two opposite directions in the second direction, and improve the resistance of the battery pack to the impact in the second direction, thereby improving the reliability of the battery pack.

[0074] The battery device disclosed in the embodiment of the present application can be used in, but not limited to, electrical devices such as vehicles, ships, or aircraft. A power supply system of the electrical device can be composed of the battery device disclosed in the present application.

[0075] The embodiment of the present application provides an electric device using a battery device as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, the electric toy may include a fixed or mobile electric toy, for example, a game console, an electric car toy, an electric ship toy, an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, a spacecraft, etc.

[0076] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electric device 1000 of an embodiment of the present application. Figure 1 , Figure 1 The power consumption device 1000 provided for some embodiments of the present application is a schematic diagram of the structure of a vehicle. The vehicle can be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery device 100 is provided inside the vehicle, and the battery device 100 can be provided at the bottom, head or tail of the vehicle. The battery device 100 can be used to power the vehicle, for example, the battery device 100 can be used as an operating power source for the vehicle. The vehicle may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery device 100 to power the motor 300, for example, for starting, navigating and driving the vehicle. Working power requirements.

[0077] In some embodiments of the present application, the battery device 100 can be used not only 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.

[0078] Please refer to Figure 2 , Figure 2The structural exploded diagram of the battery device 100 provided for some embodiments of the present application. The battery device 100 includes a box body 1 and a plurality of battery cells 23A, and the battery cells 23A are used to be accommodated in the box body 1. Among them, the box body 1 is used to provide an assembly space for the battery cells 23A, and the box body 1 can adopt a variety of structures. In some embodiments, the box body 1 may include a first box body 11 and a second box body 12, and the first box body 11 and the second box body 12 cover each other, and the first box body 11 and the second box body 12 jointly define an assembly space for accommodating the battery cells 23A. The second box body 12 can be a hollow structure with one end open, and the first box body 11 can be a plate-like structure. The first box body 11 covers the open side of the second box body 12, so that the first box body 11 and the second box body 12 jointly define the assembly space; the first box body 11 and the second box body 12 can also be hollow structures with one side open, and the open side of the first box body 11 covers the open side of the second box body 12. Of course, the box body 1 formed by the first box body 11 and the second box body 12 can be in various shapes, such as a cylinder, a cuboid, etc.

[0079] In the battery device 100, multiple battery cells 23A can be connected in series, in parallel, or in mixed connection. Mixed connection means that multiple battery cells 23A are connected in series and in parallel. Multiple battery cells 23A can be directly connected in series, in parallel, or in mixed connection, and then the whole formed by multiple battery cells 23A is accommodated in the box 1; of course, the battery device 100 can also be a battery module formed by multiple battery cells 23A connected in series, in parallel, or in mixed connection, and multiple battery modules are then connected in series, in parallel, or in mixed connection to form a whole, and accommodated in the box 1. The battery device 100 can also include other structures. For example, the battery device 100 can also include a converging component for realizing electrical connection between multiple battery cells 23A.

[0080] Please refer to Figure 2 , Figure 2 The structure of the battery device 100 provided in some embodiments of the present application is exploded. The battery device 100 includes multiple rows of battery cells 23A, which are arranged along the length direction of the box body 1, and each row of battery cells 23A includes multiple battery cells 23A arranged along the width direction of the box body 1; or, multiple rows of battery cells 23A are arranged along the width direction of the box body 1, and each row of battery cells 23A includes multiple battery cells 23A arranged along the length direction of the box body 1.

[0081] Each battery cell 23A may be a secondary battery or a primary battery, wherein a secondary battery refers to a battery cell 23A that can be continuously used by activating the active material by charging after the battery cell is discharged; it may also 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-acid battery, etc., which is not limited in the embodiments of the present application. The battery cell 23A may be cylindrical, flat, rectangular, or in other shapes. For example, in Figure 2 In the embodiment, the battery cell 23A is in the shape of a cuboid, and the height direction of the battery cell 23A is the second direction Z, the length direction of the battery cell 23A is the third direction Y, and the thickness direction of the battery cell 23A is the first direction X. The first direction X, the third direction Y, and the second direction Z are perpendicular to each other. However, it is not limited to this. In other embodiments of the present application, the battery cell 23A may also be in the shape of a polygonal prism, a flat body, or other shapes.

[0082] Please refer to Figure 3-Figure 5 In an embodiment of the present application, the battery device 100 includes a battery pack 2 .

[0083] The battery pack 2 includes a first shell 21, a second shell 22 and a plurality of soft-pack battery cells 23. The first shell 21 and the second shell 22 are arranged in sequence along a first direction, and the first shell 21 and the second shell 22 are connected. The first shell 21 has a first U-shaped mounting cavity 21a, and the second shell 22 has a second U-shaped mounting cavity 22a. A plurality of soft-pack battery cells 23 are respectively arranged in the first U-shaped mounting cavity 21a and the second U-shaped mounting cavity 22a. The first U-shaped mounting cavity 21a and the second U-shaped mounting cavity 22a are used to limit the movement of the soft-pack battery cells 23 therein from two opposite directions in a second direction, and the second direction is perpendicular to the first direction.

[0084] It can be seen that a plurality of soft-pack battery cells 23 are provided in the first shell 21, and a plurality of soft-pack battery cells 23 are also provided in the second shell 22. The first shell 21 and the second shell 22 can respectively play a certain role in protecting and supporting the soft-pack battery cells 23 therein; the first shell 21 and the second shell 22 are connected to each other, so as to realize the connection between the module composed of the first shell 21 and the plurality of soft-pack battery cells 23 therein and the module composed of the second shell 22 and the plurality of soft-pack battery cells therein, so as to facilitate the battery pack 2 to be better connected as an integral structure, facilitate the assembly of the battery pack 2 itself and can be installed as a whole, and at the same time be beneficial to enhance the structural strength of the battery pack 2, and improve the main frequency of the battery pack 2, that is, to improve the overall vibration frequency of the battery pack 2, and improve the mechanical properties of the battery pack 2.

[0085] It can be understood that in the embodiment of the present application, there is no specific limitation on the connection method between the first shell 21 and the second shell 22; for example, the first shell 21 and the second shell 22 can adopt at least one of the following connection methods: bonding, welding, threaded connection, riveting, etc.

[0086] Compared with some technologies, two adjacent shells each containing a plurality of soft-pack battery cells are fixed separately, and each shell and the plurality of soft-pack battery cells therein constitute a module, and adjacent modules are independently arranged and not connected, and each module is fixed separately, for example, each module is fixed to the box separately; the above scheme of the present application can improve the overall strength of the battery pack 2, so that the battery pack 2 is better connected into a whole, thereby helping to improve the overall structural strength of the battery device 100 and improve the main frequency of the battery device 100.

[0087] It can be understood that the U-shaped mounting cavity can have two first cavity walls arranged opposite to each other along the first direction and a second cavity wall connected between the two first cavity walls, and the U-shaped mounting cavity has an opening on the side opposite to the second cavity wall in the second direction, and the second cavity wall can limit the movement of multiple soft-pack battery cells 23 in the U-shaped mounting cavity in the second direction. Exemplarily, the first shell 21 has a first U-shaped mounting cavity 21a, then the first U-shaped mounting cavity 21a may have a first opening, and multiple soft-pack battery cells 23 may be mounted on the first shell 21 through the first opening, and the first shell 21 has a first limiting shell wall 21b opposite to the first opening, the first limiting shell wall 21b is configured as the second cavity wall of the first U-shaped mounting cavity 21a, and is used to limit the movement of the multiple soft-pack battery cells 23 in the first shell 21; similarly, the second shell 22 has a second U-shaped mounting cavity 22a, then the second U-shaped mounting cavity 22a has a second opening, and multiple soft-pack battery cells 23 may be mounted on the second shell 22 through the second opening, and the second shell 22 has a second limiting shell wall 22b opposite to the second opening, the second limiting shell wall 22b is configured as the second cavity wall of the second U-shaped mounting cavity 22a, and is used to limit the movement of the multiple soft-pack battery cells 23 in the second shell 22.

[0088] In addition, the first U-shaped mounting cavity 21a and the second U-shaped mounting cavity 22a are used to limit the movement of the soft-pack battery cell 23 therein from two opposite directions in the second direction. Then, the first U-shaped mounting cavity 21a can be used to limit the movement of the soft-pack battery cell 23 therein along the forward direction, and the second U-shaped mounting cavity 22a can be used to limit the movement of the soft-pack battery cell 23 therein along the reverse direction. "Forward" and "reverse" are relative concepts, and the two directions are opposite and parallel to the second direction.

[0089] For example, the first U-shaped installation cavity 21a has a first opening and a first limiting shell wall 21b, and the first opening and the first limiting shell wall 21b are opposite to each other along the second direction. The second U-shaped installation cavity 22a has a second opening and a second limiting shell wall 22b, and the second opening and the second limiting shell wall 22b are opposite to each other along the second direction. The first limiting shell wall 21b is located on one side of the first shell 21 in the second direction, and the second limiting shell wall 22b is located on the other side of the second shell 22 in the second direction; that is, the open ends of the first shell 21 and the second shell 22 in the second direction (the ends where the first opening and the second opening are located) are arranged on opposite sides.

[0090] For example, taking the first direction as the left-right direction and the second direction as the up-down direction as an example, the first U-shaped mounting cavity 21a can be used to limit the upward movement of the soft-pack battery monomer 23 therein, and the second U-shaped mounting cavity 22a can be used to limit the downward movement of the soft-pack battery monomer 23 therein, the first limiting shell wall 21b is located at the upper end of the first shell 21, the first opening is located at the lower end of the first shell 21, the second limiting shell wall 22b is located at the lower end of the first shell 21, and the second opening is located at the upper end of the second shell 22. Of course, the first U-shaped mounting cavity 21a can be used to limit the downward movement of the soft-pack battery monomer 23 therein, and the second U-shaped mounting cavity 22a can be used to limit the upward movement of the soft-pack battery monomer 23 therein.

[0091] It can be understood that the first limiting shell wall 21b and the second limiting shell wall 22b can not only limit the movement of the corresponding soft-pack battery cell 23 in the second direction, but also resist the impact in the second direction. Then, in the embodiment of the present application, the first U-shaped installation cavity 21a and the second U-shaped installation cavity 22a are used to limit the movement of the soft-pack battery cell 23 therein from two opposite directions in the second direction, so that the first shell 21 and the second shell 22 can be used to resist the impact from two opposite directions in the second direction respectively. Then, the battery pack 2 can withstand the impact from two opposite directions in the second direction, which is beneficial to improve the balance of the entire battery pack 2 in resisting the impact in the two opposite directions in the second direction, and improve the resistance of the battery pack 2 to the impact in the second direction, thereby improving the reliability of the battery pack 2 and the reliability of the battery device 100.

[0092] In the above technical solution, the first shell 21 and the second shell 22 can respectively play a certain role in protecting and supporting the soft-pack battery cells 23 therein; and the first shell 21 and the second shell 22 are connected to each other, so that the module formed by the first shell 21 and the plurality of soft-pack battery cells 23 therein can be connected to the module formed by the second shell 22 and the plurality of soft-pack cells therein, so that the battery pack 2 can be better connected into an integral structure, and the assembly of the battery pack 2 itself is convenient and can be installed as a whole, and at the same time, it is beneficial to enhance the structural strength of the battery pack 2, and improve the main frequency of the battery pack 2, that is, to improve the overall vibration frequency of the battery pack 2, and improve the mechanical properties of the battery pack 2. Mechanical properties, thereby improving the reliability of the battery device 100; in addition, the first U-shaped mounting cavity 21a and the second U-shaped mounting cavity 22a are used to limit the movement of the soft-pack battery cell 23 therein from two opposite directions in the second direction, so that the first shell 21 and the second shell 22 can be used to resist impacts from two opposite directions in the second direction, respectively, and the battery pack 2 can withstand impacts from two opposite directions in the second direction, which is beneficial to improving the balance of the entire battery pack 2 in resisting impacts from two opposite directions in the second direction, and improving the resistance of the battery pack 2 to impacts in the second direction, thereby improving the reliability of the battery pack 2.

[0093] Please refer to Figure 4-Figure 6 In some embodiments, the portion of the first shell 21 connected to the second shell 22 extends into the second U-shaped installation cavity 22a, and the portion of the second shell 22 connected to the first shell 21 extends into the first U-shaped installation cavity 21a. It can be seen that the first shell 21 extends into the second U-shaped installation cavity 22a, the second shell 22 extends into the first U-shaped installation cavity 21a, and the portion of the first shell 21 extending into the second U-shaped installation cavity 22a is connected to the portion of the second shell 22 extending into the first U-shaped installation cavity 21a.

[0094] In the above technical solution, by setting the part of the first shell 21 extending into the second U-shaped installation cavity 22a to be connected with the part of the second shell 22 extending into the first U-shaped installation cavity 21a, the connection between the first shell 21 and the second shell 22 can not only limit the separation of the first shell 21 and the second shell 22 through the connection position between the two, but the first shell 21 and the second shell 22 themselves can limit the separation of the two, thereby improving the connection strength between the first shell 21 and the second shell 22 and improving the connection reliability of the first shell 21 and the second shell 22.

[0095] In addition, in some technologies, two adjacent shells each containing a plurality of soft-pack battery cells are fixed separately, and each shell and the plurality of soft-pack battery cells therein constitute a module. Adjacent modules are independently arranged and not connected, which will occupy more locking space. The above arrangement can also save locking parts for connecting the first shell 21 and the second shell 22, and / or save space for the above locking parts, thereby reducing the volume and occupied space of the battery pack 2, which is beneficial to improving the space utilization rate of the battery device 100, reducing space waste, and facilitating increasing the energy density of the battery device 100 under the same volume. If the battery pack 2 is glued and fixed to the box body 1, it can facilitate appropriately reducing the glue coating area between the battery pack 2 and the box body 1 while achieving reliable connection between the battery pack 2 and the box body 1, thereby improving processing efficiency.

[0096] It can be understood that the portion of the first shell 21 extending into the second U-shaped installation cavity 22a will be restricted by the shell wall of the second shell 22 and cannot move away from the second shell 22. Similarly, the portion of the second shell 22 extending into the first U-shaped installation cavity 21a will be restricted by the shell wall of the first shell 21 and cannot move away from the first shell 21. Therefore, the connection strength between the first shell 21 and the second shell 22 does not only rely on the bearing capacity of the connecting parts, but the strength and rigidity of the first shell 21 and the second shell 22 themselves also make the connection between the two more secure.

[0097] For example, Figure 4-Figure 8 As shown, the first shell 21 includes a first shell wall 211, a second shell wall 212 and a third shell wall 213, the first shell wall 211 and the second shell wall 212 are spaced apart along the first direction, the third shell wall 213 is connected to one end of the first shell wall 211 and the second shell wall 212 in the second direction, the second shell 22 includes a fourth shell wall 221, a fifth shell wall 222 and a sixth shell wall 223, the fourth shell wall 221 is adjacent to and fixedly connected to the second shell wall 212, and the fourth shell wall 221 and the fifth shell wall 222 are spaced apart along the first direction, and the sixth shell wall 223 is connected to the other end of the fourth shell wall 221 and the fifth shell wall 222 in the second direction; wherein, in the first direction, the second shell wall 212 and the fourth shell wall 221 are located between the first shell wall 211 and the fifth shell wall 222, and the fourth shell wall 221 is located on the side of the second shell wall 212 facing the first shell wall 211, so that the first shell 21 and the second shell 22 are cross-arranged.

[0098] In some embodiments, a reinforcement protrusion is provided on the outer surface of at least one of the first shell 21 and the second shell 22 .

[0099] In the above technical solution, by providing a reinforcing protrusion on the outer surface of at least one of the first shell 21 and the second shell 22, the structural strength of the above at least one of the first shell 21 and the second shell 22 can be improved. At the same time, the provision of the reinforcing protrusion will not occupy the arrangement space provided by the above at least one of the first shell 21 and the second shell 22 for the soft-pack battery cell 23, nor will it affect the flatness of the inner surface of the above at least one of the first shell 21 and the second shell 22, so that the inner surface of the first shell 21 and the inner surface of the second shell 22 can still provide a relatively flat limiting surface for the soft-pack battery therein, so that the reinforcing protrusion is not easy to excessively squeeze the soft-pack battery cell 23 and cause lithium plating problems.

[0100] In the embodiment of the present application, the position of the reinforcing protrusion is not specifically limited; taking the case where the outer surface of the first shell 21 is provided with a reinforcing protrusion as an example: the first shell 21 includes a first shell wall 211, a second shell wall 212 and a third shell wall 213, the first shell wall 211 and the second shell wall 212 are spaced apart along the first direction, the third shell wall 213 is connected to one end of the first shell wall 211 and the second shell wall 212 in the second direction, and at least one of the first shell wall 211, the second shell wall 212 and the third shell wall 213 has a reinforcing protrusion on one side facing away from the first U-shaped mounting cavity 21a.

[0101] In addition, when the outer surface of the first shell 21 and the outer surface of the second shell 22 are respectively provided with reinforcing protrusions, the reinforcing protrusions on the first shell 21 and the reinforcing protrusions on the second shell 22 can be located on the same side or different sides of the battery pack 2, and the reinforcing protrusions on the first shell 21 and the reinforcing protrusions on the second shell 22 can be separated or matched.

[0102] In some embodiments, the battery device 100 further includes an elastic pad, which is sandwiched between the first shell 21 and the second shell 22. For example, there is a cavity between the first shell 21 and the second shell 22, and the elastic pad is disposed in the cavity.

[0103] In the above technical solution, an elastic pad is sandwiched between the first shell 21 and the second shell 22 to reserve a certain space for the deformation of the first shell 21 and the second shell 22. At the same time, the elastic pad can absorb the deformation of the first shell 21 and the second shell 22. It is not easy for a large extrusion force to be generated between the first shell 21 and the second shell 22 due to deformation, which is beneficial to reducing the extrusion force generated by the deformation of the first shell 21 and the second shell 22 on the soft-pack battery cell 23, thereby reducing the risk of lithium deposition of the soft-pack battery cell 23.

[0104] Optionally, the elastic pad is a thermal insulation member, so that the elastic pad has good thermal insulation performance.

[0105] In the above technical solution, by setting the elastic pad as a heat insulating member, the heat transfer between the first shell 21 and the second shell 22 can be reduced, so that the elastic pad can not only prolong the heat transfer time between the first shell 21 and the second shell 22, and delay the occurrence speed of thermal runaway of adjacent modules, but also reduce the risk of thermal runaway of adjacent modules, thereby helping to improve the thermal stability and reliability of the battery device 100. It can be understood that the material and structure of the heat insulating member can be specifically set according to actual needs.

[0106] Please refer to Figure 4-Figure 6 In some embodiments, the first shell 21 includes a first shell wall 211, a second shell wall 212 and a third shell wall 213, the first shell wall 211 and the second shell wall 212 are spaced apart along the first direction, the third shell wall 213 is connected to one end of the first shell wall 211 and the second shell wall 212 in the second direction to close one end of the first U-shaped installation cavity 21a in the second direction, and the third shell wall 213 is used to limit the movement of the internal soft-pack battery cell 23; the second shell 22 includes a fourth shell wall 221, a fifth shell wall 222 and a sixth shell wall 223, the fourth shell wall 221 is adjacent to and fixedly connected to the second shell wall 212, and the fourth shell wall 221 and the fifth shell wall 222 are spaced apart along the first direction, the sixth shell wall 223 is connected to the other end of the fourth shell wall 221 and the fifth shell wall 222 in the second direction to close one end of the second U-shaped installation cavity 22a in the second direction, and the sixth shell wall 223 is used to limit the movement of the internal soft-pack battery cell 23.

[0107] It can be seen that the second shell wall 212 and the fourth shell wall 221 are located between the first shell wall 211 and the fifth shell wall 222. The first shell wall 211, the second shell wall 212 and the third shell wall 213 define the first U-shaped installation cavity 21a, and all three are the cavity walls of the first U-shaped installation cavity 21a. The fourth shell wall 221, the fifth shell wall 222 and the sixth shell wall 223 define the second U-shaped installation cavity 22a, and all three are the cavity walls of the second U-shaped installation cavity 22a. The structure of the first shell wall 211 and the second shell 22 is simple and convenient to process, and it is convenient to connect the first shell 21 and the second shell 22.

[0108] Please refer to Figure 4-Figure 6 In some embodiments, the fourth shell wall 221 is located on the side of the second shell wall 212 facing the first shell wall 211, and the fourth shell wall 221 extends into the first U-shaped installation cavity 21a, and the second shell wall 212 extends into the second U-shaped installation cavity 22a, so that the parts of the first shell 21 and the second shell 22 that extend into each other are connected.

[0109] In the above technical solution, by setting the fourth shell wall 221 on the side of the second shell wall 212 facing the first shell wall 211, and the fourth shell wall 221 is fixedly connected to the second shell wall 212, the connection between the first shell 21 and the second shell 22 is cross-connected. At this time, the first shell 21 and the second shell 22 can not only limit the separation of the first shell 21 and the second shell 22 through the connection position between the two, but the second shell wall 212 itself can limit the fourth shell wall 221 away from the first shell 21, and the fourth shell wall 221 itself can limit the second shell wall 212 away from the second shell 22, so that the first shell 21 and the second shell 22 can limit the separation of the two from each other, thereby improving the connection strength between the first shell 21 and the second shell 22, and improving the connection reliability of the first shell 21 and the second shell 22.

[0110] Of course, in other embodiments of the present application, the fourth shell wall 221 can also be located on the side of the second shell wall 212 away from the first shell wall 211. In this case, the fourth shell wall 221 can be located outside the first U-shaped mounting cavity 21a, and the second shell wall 212 is located outside the second U-shaped mounting cavity 22a. The connection between the second shell wall 212 and the fourth shell wall 221 can also be achieved. Moreover, the height dimension of the second shell wall 212 is not easily restricted by the second U-shaped mounting cavity 22a, and the height dimension of the fourth shell wall 221 is not easily restricted by the first U-shaped mounting cavity 21a, so the structure is more flexible.

[0111] Please refer to Figure 4-Figure 6 In some embodiments, the fourth shell wall 221 is located on the side of the second shell wall 212 facing the first shell wall 211, the free end of the second shell wall 212 stops at the connection position between the fourth shell wall 221 and the sixth shell wall 223, and the free end of the fourth shell wall 221 stops at the connection position between the second shell wall 212 and the third shell wall 213. Thus, the second shell 22 can limit the movement of the first shell 21 in the second direction by cooperating with the second shell wall 212, and the first shell 21 can limit the movement of the second shell 22 in the second direction by cooperating with the fourth shell wall 221. The cross-cooperation between the two facilitates the operator to promptly determine whether the first shell 21 and the second shell 22 are assembled in place.

[0112] The free end of the second shell wall 212 can be understood as an end of the second shell wall 212 away from the third shell wall 213 , and the free end of the fourth shell wall 221 can be understood as an end of the fourth shell wall 221 away from the sixth shell wall 223 .

[0113] In the above technical solution, by setting the free end of the second shell wall 212 to stop at the connection position between the fourth shell wall 221 and the sixth shell wall 223, and the free end of the fourth shell wall 221 to stop at the connection position between the second shell wall 212 and the third shell wall 213, it is convenient to realize the positioning of the first shell 21 and the second shell 22 in the second direction during the assembly process, and it is convenient to fix the first shell 21 and the second shell 22 in the subsequent process, which is conducive to improving the assembly convenience and assembly efficiency of the battery pack 2. Obviously, the above arrangement allows the first shell 21 and the second shell 22 of the battery pack 2 to be assembled independently and conveniently, and the battery pack 2 as a whole can also be assembled conveniently.

[0114] Optionally, when the fourth shell wall 221 is located on the side of the second shell wall 212 facing the first shell wall 211 , the fourth shell wall 221 may be disposed in close contact with the surface of the side of the second shell wall 212 facing the first shell wall 211 .

[0115] Please refer to Figure 4-Figure 8 In some embodiments, each of the first shell wall 211, the second shell wall 212, the fourth shell wall 221 and the fifth shell wall 222 is configured to include a first plate portion 31 and a second plate portion 32 arranged and connected along the second direction, the second plate portion 32 and the pole ear 231 of the soft-pack battery cell 23 are staggered in the second direction, and the first plate portion 31 and the pole ear 231 are opposite to each other along the first direction; in the third direction, the length of the first plate portion 31 is greater than the length of the second plate portion 32, and the pole ear 231 extends between one end of the length of the first plate portion 31 and one end of the length of the second plate portion 32, then in the third direction, the pole ear 231 extends to an end beyond the corresponding length of the second plate portion 32, and the pole ear 231 extends to an end that does not exceed the corresponding length of the first plate portion 31.

[0116] In the above technical solution, by setting the first plate portion 31 and the second plate portion 32, the first plate portion 31 can play a certain protective role on the pole ear 231, so that when the battery pack 2 is assembled with other components such as a busbar, the pole ear 231 is not easy to interfere with other components, which can reduce the probability of scratching the pole ear 23 by other components. At the same time, the amount of material used in the first shell 21 and the second shell 22 is relatively small, which is conducive to reducing material costs.

[0117] It can be understood that for multiple soft-pack battery cells 23 in the same U-shaped mounting cavity (the first U-shaped mounting cavity 21a or the second U-shaped mounting cavity 22a), at least two pole ears 231 of the multiple soft-pack battery cells 23 can be gathered and connected. Of course, the pole ears 231 of the multiple soft-pack battery cells 23 can also be independent.

[0118] In some embodiments, at least one outer surface of the first shell wall 211, the third shell wall 213, the fifth shell wall 222 and the sixth shell wall 223 is provided with a reinforcing protrusion, which can enhance the structural strength of at least one of the first shell wall 211, the third shell wall 213, the fifth shell wall 222 and the sixth shell wall 223, and the reinforcing protrusion is not easy to interfere with the connection setting between the first shell 21 and the second shell 22; and / or, at least one of the side surfaces of the second shell wall 212 and the fourth shell wall 221 opposite to each other is provided with a reinforcing protrusion, which can enhance the structural strength of the second shell wall 212 and the fourth shell wall 221, which is conducive to further enhancing the connection strength and connection reliability between the first shell 21 and the second shell 22.

[0119] In the above technical solution, the setting of the reinforcing protrusion can improve the structural strength of at least one of the first shell 21 and the second shell 22, while not occupying the arrangement space provided by at least one of the first shell 21 and the second shell 22 for the soft-pack battery cell 23, and not affecting the flatness of the inner surface of at least one of the first shell 21 and the second shell 22, so that the inner surface of the first shell 21 and the inner surface of the second shell 22 can still provide a relatively flat limiting surface for the soft-pack battery therein, so that the reinforcing protrusion is not easy to excessively squeeze the soft-pack battery cell 23 and cause lithium plating problems.

[0120] In some embodiments, the reinforcing protrusion is configured as a rib or a convex point. Thus, the reinforcing protrusion has a simple structure and is easy to process. It is understood that when the reinforcing protrusion is a rib, the cross-sectional shape of the rib and the extension direction of the rib can be specifically set according to requirements.

[0121] Please refer to Figure 4-Figure 6 In some embodiments, the first shell 21 and the second shell 22 are separate parts.

[0122] In the above technical solution, by setting the first shell 21 and the second shell 22 as separate parts, the two are fixedly connected by assembly means, allowing the first shell 21 and the second shell 22 to be more flexibly adjusted during the assembly process, so as to adapt to different installation environments. In particular, when there are differences in the number and size of the soft-pack battery cells 23, the split-design structure can more easily adapt to these changes so that the battery pack 2 can be installed correctly and stably. In addition, in the split-design structure, if the first shell 21 and the second shell 22 are set to be detachably connected, when the battery pack 2 needs to be maintained or replaced, it can be more easily partially disassembled and reinstalled, which reduces maintenance costs and improves maintenance efficiency.

[0123] Of course, in other embodiments of the present application, the first shell 21 and the second shell 22 may also be an integral piece, thereby saving the connection process between the first shell 21 and the second shell 22, which is beneficial to improving the assembly efficiency of the battery pack 2.

[0124] Please refer to Figure 3 In some embodiments, the first shell 21 and the second shell 22 are multiple, and the multiple first shells 21 and the multiple second shells 22 are alternately arranged one by one along the first direction, so that one first shell 21 is provided between two adjacent second shells 22, and one second shell 22 is provided between two adjacent first shells 21.

[0125] In the above technical solution, by arranging multiple first shells 21 and multiple second shells 22 alternately along the first direction, the regular arrangement of the first shells 21 and the second shells 22 in the battery pack 2 is facilitated, which is beneficial to further enhance the ability of the entire battery pack 2 to resist impact in the second direction, and is beneficial to enhance the balancing ability of the entire battery pack 2 to resist impact in the opposite direction in the second direction.

[0126] It can be understood that in the embodiments of the present application, the battery pack 2 can be constructed into any one of the following multiple examples: Example 1, the battery pack 2 includes a first shell 21 and two second shells 22, and the first shell 21 is arranged between the two second shells 22 in the first direction; Example 2, the battery pack 2 includes a second shell 22 and two first shells 21, and the second shell 22 is arranged between the two first shells 21 in the first direction; Example 3, the battery pack 2 includes multiple first shells 21 and multiple second shells 22, and the multiple first shells 21 and the multiple second shells 22 are alternately arranged one by one along the first direction.

[0127] It can be understood that in the embodiment of the present application, the battery group 2 of the battery device 100 can be one group or multiple groups, and the settings of the multiple groups of battery groups 2 can be specifically arranged according to actual needs; for example, the multiple groups of battery groups 2 can be arranged along the second direction and / or the third direction, and the first direction and the second direction are respectively perpendicular to the third direction.

[0128] Please refer to Figure 3 In some embodiments, the battery device 100 further includes a box body 1, which has a accommodating cavity 1a, and the battery pack 2 is disposed in the accommodating cavity 1a. By arranging the battery pack 2 in the accommodating cavity 1a, the accommodating cavity 1a provides a relatively closed environment for the battery pack 2, so that the battery pack 2 is not easily disturbed by the external environment during operation.

[0129] The closed end of the first U-shaped mounting cavity 21a in the second direction is fixedly connected to the box body 1, and the closed end of the second U-shaped mounting cavity 22a in the second direction is fixedly connected to the box body 1, which is beneficial to increase the connection area between the first shell 21 and the box body 1, and improve the connection strength and connection reliability of the first shell 21 and the box body 1. It is also beneficial to increase the connection area between the second shell 22 and the box body 1, and improve the connection strength and connection reliability of the second shell 22 and the box body 1; and / or the battery device 100 also includes a first connecting plate and a second connecting plate, and the first connecting plate closes the first The second connecting plate closes the open end of the second U-shaped mounting cavity 21a in the second direction, and the first shell 21 is fixedly connected to the box body 1 through the first connecting plate, and the second shell 22 is fixedly connected to the box body 1 through the second connecting plate. The setting of the first connecting plate and the second connecting plate can improve the limiting reliability of the soft-pack battery cell 23 in the second direction, and at the same time, an intermediate transition can be provided for the connection between the first shell 21 and the second shell 22 and the box body 1, which facilitates the connection between the first shell 21 and the second shell 22 and the box body 1.

[0130] It can be understood that the closed end of the first U-shaped mounting cavity 21a in the second direction is used to limit the movement of the soft-pack battery cell 23 in the first U-shaped mounting cavity 21a in the second direction, and the closed end of the second U-shaped mounting cavity 22a in the second direction is used to limit the movement of the soft-pack battery cell 23 in the second U-shaped mounting cavity 22a in the second direction; for example, the first limiting shell wall 21b mentioned above is fixedly connected to the box body 1, and the second limiting shell wall 22b is fixedly connected to the box body 1.

[0131] Taking the second direction as the up-down direction as an example, for the first shell 21, if the lower end of the first shell 21 is an open side, the upper end of the first shell 21 is fixedly connected to the top plate 13 of the box body 1, and the lower end of the first shell 21 is closed by the first connecting plate and fixedly connected to the bottom plate 14 of the box body 1 through the first connecting plate. At this time, both the upper and lower ends of the first shell 21 are connected to the box body 1, which can improve the installation reliability of the battery pack 2; of course, the lower end of the first shell 21 can also be provided with no first connecting plate, and the first shell 21 is directly fixed to the box body 1, such as by bonding. The same is true for the second shell 22, which will not be repeated here.

[0132] In some embodiments, the battery device 100 also includes at least one of a first heat exchange member and a second heat exchange member, and the at least one of the first heat exchange member and the second heat exchange member is used for heat exchange with the soft-pack battery cell 23. The first heat exchange member is arranged between the first shell 21 and the second shell 22, and the second heat exchange member is arranged between the battery pack 2 and the box body 1.

[0133] It can be seen that the first heat exchange member is arranged between the first shell 21 and the second shell 22, so that the first heat exchange member can perform heat exchange with the soft-pack battery cells 23 in the first shell 21 and the second shell 22, so that the operating temperature of the soft-pack battery cells 23 can be maintained within a relatively appropriate range, which helps to reduce the temperature difference between the soft-pack battery cells 23 and is convenient for improving the working stability of the battery device 100. In addition, by arranging the first heat exchange member between the first shell 21 and the second shell 22, it is convenient to make full use of the space inside the battery device 100, improve the space utilization rate, and facilitate the miniaturization design of the battery device 100; the second heat exchange member is arranged between the battery pack 2 and the box 1, which is also convenient for maintaining the temperature of the soft-pack battery cells 23 within a suitable range and improving the reliability of the battery device 100. The heat transfer through the second heat exchange member can further enhance the thermal management capability of the battery device 100, which helps to keep the internal temperature of the battery device 100 within a reasonable range when the battery device 100 is working, thereby improving the working efficiency and stability of the battery device 100.

[0134] Optionally, the first heat exchange element and the second heat exchange element may be configured as heat exchange plates or heat exchange tubes.

[0135] Optionally, a second heat exchange member may be provided on one side of the battery pack 2 in the second direction, and / or a second heat exchange member may be provided on one side of the battery pack 2 in the third direction. Figure 3 , Figure 9-11 A second heat exchange component may be provided between the top plate 13 of the box body 1 and the battery pack 2, and / or a second heat exchange component may be provided between the bottom plate 14 of the box body 1 and the battery pack 2, and / or a second heat exchange component may be provided between at least one of the multiple side walls of the box body 1 and the battery pack 2.

[0136] In some embodiments of the present application, the soft pack battery cell 23 is any one of a lithium iron phosphate battery cell, a ternary battery cell and a solid-state battery cell. Among them, the solid-state battery cell can be, but is not limited to, a polymer solid-state battery cell, an oxide solid-state battery cell, a sulfide solid-state battery cell, a halide solid-state battery cell, etc. The solid-state battery cell can also be a semi-solid-state battery cell or a fully solid-state battery cell.

[0137] In the above technical solution, the soft-pack battery cell 23 adopts the above types to provide more options for the design of the battery device 100 to meet different usage requirements. Among them, the soft-pack battery cell 23 is a lithium iron phosphate battery cell, which has the advantages of high reliability, long cycle life, light weight, large capacity, and low internal resistance; the soft-pack battery cell 23 is a ternary battery cell, which has the advantages of high energy density and good electrochemical performance; the soft-pack battery cell 23 is a solid-state battery cell, which has the advantages of high energy density and high reliability, light weight, and good high and low temperature performance.

[0138] In some embodiments of the present application, the soft-pack battery cell 23 is a lithium iron phosphate battery cell, and in the positive electrode material of the soft-pack battery cell 23, the usage ratio of the positive electrode active material, the binder, and the conductive agent is 96: (1-3): (1-3); the soft-pack battery cell 23 is a ternary battery cell, and in the positive electrode material of the soft-pack battery cell 23, the usage ratio of the positive electrode active material, the binder, and the conductive agent is 96: (2-3): (1-2).

[0139] In the above technical solution, when the soft-pack battery cell 23 is a lithium iron phosphate battery cell, a high proportion of positive electrode active material means that more substances capable of electrochemical reactions can be accommodated in a limited electrode assembly, which is beneficial to increasing the capacity and energy density of the battery device 100, so that the lithium iron phosphate battery cell can output a higher amount of electricity in a relatively small volume and weight, meeting the application scenario with certain requirements for energy density. The amount of the binder and the conductive agent used in the above range can reduce the cost of auxiliary materials, thereby reducing the overall cost of the battery device 100. When the soft-pack battery cell 23 is a ternary battery cell, since the structure and surface properties of the ternary material itself are relatively complex, the use of the positive electrode active material, binder, and conductive agent in the above-mentioned dosage ratio is beneficial to ensure good bonding between the positive electrode active material particles and between the active material and the current collector, thereby improving the mechanical stability and integrity of the electrode assembly, and is beneficial to reducing the risk of active material shedding and electrode pulverization during charging and discharging, and extending the cycle life of the battery device 100.

[0140] In some embodiments, the positive electrode of the soft-pack battery cell 23 may be a positive electrode sheet, which may include a positive electrode collector and a positive electrode film layer disposed on at least one surface of the positive electrode collector, wherein the positive electrode film layer includes a positive electrode active material.

[0141] As an example, the positive electrode current collector has two surfaces opposite to each other in its thickness direction, and the positive electrode film layer is disposed on any one or both of the two opposite surfaces of the positive electrode current collector.

[0142] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, titanium, silver surface treated aluminum or stainless steel, etc. may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0143] As an example, when the soft-pack battery cell 23 of the embodiment of the present application is a lithium-ion battery, the positive electrode active material may include at least one of the following materials: phosphate, layered transition metal oxide and their respective modified compounds; Optionally, the positive electrode active material may include layered transition metal oxide and their respective modified compounds, which is beneficial to improve the energy density of the soft-pack battery cell 23. However, the present application is not limited to these materials, and other traditional materials that can be used as battery positive electrode film layers can also be used. These positive electrode active materials can be used alone or in combination of two or more.

[0144] Examples of phosphates may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon.

[0145] Layered transition metal oxides include Li a Ni b Co c M d O e A f At least one of the compounds and modified compounds thereof. 0.8≤a≤1.2, 0.3≤b<1, 0<c<1, 0<d<1, 1≤e≤2, 0≤f≤1, M includes at least one of Mn, Al, Zr, Zn, Cu, Cr, Mg, Fe, V, Ti and B, and A includes at least one of N, F, S and Cl. Optionally, 0.5≤b<1, further optionally, 0.75≤b≤0.98.

[0146] Examples of layered transition metal oxides may include, but are not limited to, lithium cobalt oxide (e.g., LiCoO2), lithium nickel oxide (e.g., LiNiO2), lithium manganese oxide (e.g., LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also referred to as NCM 333 )、LiNi 0.5 Co 0.2 Mn 0.3 O2 (also referred to as NCM 523 )、LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM 211 )、LiNi 0.6 Co 0.2 Mn 0.2O2 (also referred to as NCM 622 )、LiNi 0.8 Co 0.1 Mn 0.1 O2 (also referred to as NCM 811 )、LiNi 0.9 Co 0.05 Mn 0.05 O2 (also referred to as Ni90), lithium nickel cobalt aluminum oxide (such as LiNi 0.80 Co 0.15 Al 0.05 O2) and its modified compounds, etc.

[0147] When the soft-pack battery cell 23 of the embodiment of the present application is a sodium ion battery, the positive electrode active material may include but is not limited to at least one of sodium-containing transition metal oxides, polyanion materials (such as phosphates, fluorophosphates, pyrophosphates, sulfates, etc.), and Prussian blue materials.

[0148] As an example, the positive electrode active material for sodium ion batteries may include NaFeO2, NaCoO2, NaCrO2, NaMnO2, NaNiO2, NaNi 1 / 2 Ti 1 / 2 O2、NaNi 1 / 2 Mn 1 / 2 O2、Na 2 / 3 Fe 1 / 3 Mn 2 / 3 O2、NaNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2, NaFePO4, NaMnPO4, NaCoPO4, Prussian blue materials, general formula X p M' q PO 4r O x Y 3-x In the general formula X p M' q PO 4r O x Y 3-x , 0<p≤4, 0<q≤2, 1≤r≤3, 0≤x≤2, X includes at least one of H+, Li+, Na+, K+ and NH4+, M' is a transition metal cation, optionally at least one of V, Ti, Mn, Fe, Co, Ni, Cu and Zn, and Y is a halogen anion, optionally at least one of F, Cl and Br.

[0149] In the embodiments of the present application, the modified compounds of the above-mentioned positive electrode active materials can be doping modification and / or surface coating modification of the positive electrode active materials, such as carbon coating modification, fast ion conductor coating modification, etc.

[0150] The charge and discharge process of the soft-pack battery cell 23 is accompanied by the deintercalation and consumption of active ions such as Li. The molar content of Li is different when the soft-pack battery cell 23 is discharged to different states. In the examples of the positive electrode active materials in the present application, the molar content of Li is the initial state of the material, that is, the state before feeding. The positive electrode active material is used in the battery system. After the charge and discharge cycle, the molar content of Li may change.

[0151] In the examples of the present application regarding the positive electrode active materials, the molar content of oxygen O is only a theoretical value. The release of oxygen from the lattice will cause the molar content of oxygen O to change. In reality, the molar content of oxygen O will fluctuate.

[0152] In the embodiments of the present application, the content of elements in the positive electrode active material has a well-known meaning in the art, and can be detected by equipment and methods well-known in the art, for example, with reference to EPA 6010D-2014, tested by inductively coupled plasma atomic emission spectrometry, and measured by plasma atomic emission (ICP-OES, instrument model: Thermo ICAP7400). First, weigh 0.4g of positive electrode active material and add 10ml (50% concentration) of aqua regia thereto. Then place it on a plate at 180°C for 30min. After digestion on the plate, dilute to a volume of 100mL, and use the standard curve method for quantitative testing.

[0153] In some embodiments, the positive electrode may be a foamed metal. The foamed metal may be a nickel foam, a copper foam, an aluminum foam, an alloy foam, or a carbon foam. When the foamed metal is used as the positive electrode, the positive electrode film layer may not be provided on the surface of the foamed metal, but of course, a positive electrode film layer may also be provided. As an example, a lithium source material, potassium metal or sodium metal may also be filled or / and deposited in the foamed metal, and the lithium source material is lithium metal and / or a lithium-rich material.

[0154] In some embodiments, the positive electrode film layer may further optionally include a positive electrode conductive agent. The present application embodiment has no particular restrictions on the type of the positive electrode conductive agent. As an example, the positive electrode conductive agent includes at least one of superconducting carbon, conductive graphite, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene and carbon nanofibers. In some embodiments, the mass percentage of the positive electrode conductive agent in the positive electrode film layer is ≤5wt%.

[0155] In some embodiments, the positive electrode film layer may also optionally include a positive electrode binder. The embodiment of the present application has no particular restrictions on the type of positive electrode binder. As an example, the positive electrode binder may include at least one of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer and fluorine-containing acrylic resin. In some embodiments, the mass percentage of the positive electrode binder in the positive electrode film layer is ≤5wt%.

[0156] The positive electrode film layer is usually formed by coating the positive electrode slurry on the positive electrode current collector, drying and cold pressing. The positive electrode slurry is usually formed by dispersing the positive electrode active material, optional conductive agent, optional binder and any other components in a solvent and stirring them evenly. The solvent can be N-methylpyrrolidone (NMP), but is not limited thereto.

[0157] In some embodiments, the negative electrode may be a negative electrode plate, which 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, wherein the negative electrode film layer includes a negative electrode active material.

[0158] As an example, the negative electrode current collector has two surfaces opposite to each other in its thickness direction, and the negative electrode film layer is disposed on any one or both of the two opposite surfaces of the negative electrode current collector.

[0159] As an example, the negative electrode current collector may be a metal foil, a foamed metal or a composite current collector. For example, as the metal foil, aluminum or stainless steel treated with silver, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. may be used. The foamed metal may be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. The composite current collector may include a polymer material base and a metal layer. The composite current collector may be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0160] As an example, the negative electrode active material may adopt the negative electrode active material for the soft-pack battery cell 23 known in the art. As an example, the negative electrode active material may include at least one of the following materials: carbon material (for example, the carbon material includes at least one of artificial graphite, natural graphite, soft carbon, and hard carbon), silicon-based material, tin-based material, lithium titanate, etc. The silicon-based material may include at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material may include at least one of elemental tin, tin oxide compounds, and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as battery negative electrode film layers may also be used. These negative electrode film layers may be used alone or in combination of two or more.

[0161] In some embodiments, the negative electrode active material includes silicon, which may be present in the form of a silicon-based material, such as a silicon-based material that may include at least one of elemental silicon, silicon-oxygen compounds, silicon-carbon compounds, silicon-nitrogen compounds, and silicon alloys. The introduction of silicon can increase the energy density of the soft-pack battery cell 23.

[0162] In some embodiments, the mass content of silicon in the negative electrode film layer is 1wt% to 32wt%, optionally 2wt% to 19wt%, and further optionally 6wt% to 13wt%. In the soft-pack battery cell 23 system, when the mass content of silicon is within the above range, the energy density of the soft-pack battery cell 23 can be improved.

[0163] In the embodiments of the present application, the mass content of silicon in the negative electrode film layer has a meaning well known in the art and can be detected by using equipment and methods well known in the art. For example, the negative electrode plate is immersed in a solvent such as water, the negative electrode active material is separated from the negative electrode current collector, and the negative electrode active material is obtained by filtration. The negative electrode active material is measured using an ICAP7400 inductively coupled plasma-emission spectrometer of ThermoFisher Scientific, USA, and with reference to GB / T30902-2014 standard to obtain the silicon content.

[0164] In some embodiments, the negative electrode film layer may further optionally include a negative electrode conductive agent. The embodiment of the present application has no particular restrictions on the type of the negative electrode conductive agent. As an example, the negative electrode conductive agent may include at least one of superconducting carbon, conductive graphite, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers. In some embodiments, the mass percentage of the negative electrode conductive agent in the negative electrode film layer is ≤5wt%.

[0165] In some embodiments, the negative electrode film layer may also optionally include a negative electrode binder. The embodiment of the present application has no particular restrictions on the type of negative electrode binder. As an example, the negative electrode binder may include at least one of styrene-butadiene rubber (SBR), water-soluble unsaturated resin SR-1B, water-based acrylic resin (e.g., polyacrylic acid PAA, polymethacrylic acid PMAA, sodium polyacrylate PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA) and carboxymethyl chitosan (CMCS). In some embodiments, the mass percentage of the negative electrode binder in the negative electrode film layer is ≤5%.

[0166] In some embodiments, the negative electrode film layer may further include other additives. As an example, the other additives may include thickeners, such as sodium carboxymethyl cellulose (CMC-Na), PTC thermistor materials, etc. In some embodiments, the mass percentage of the other additives in the negative electrode film layer is ≤ 2wt%.

[0167] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0168] In some embodiments, the separator includes a separator. The present application has no particular limitation on the type of separator, and any known separator with a porous structure having good chemical stability and mechanical stability can be selected.

[0169] The embodiments of the present application have no particular restrictions on the type of isolation membrane, and any known porous structure isolation membrane with good chemical stability and mechanical stability can be selected.

[0170] In some embodiments, the material of the isolation membrane may include one or more of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride. The isolation membrane may be a single-layer film or a multi-layer composite film, without particular limitation. When the isolation membrane is a multi-layer composite film, the materials of each layer may be the same or different, without particular limitation.

[0171] In some embodiments, the isolation membrane may include a porous base membrane and a coating disposed on at least one side of the porous base membrane, and the coating may include at least one of inorganic particles or organic particles. The porous base membrane may include one or more of polyethylene and polypropylene.

[0172] The inorganic particles have good heat resistance and can improve the heat resistance of the separator as a whole. The inorganic particles will not undergo oxidation and reduction reactions with metal dendrites within the operating voltage range of the sodium ion battery. In other words, the inorganic particles are configured not to undergo oxidation and reduction reactions with alkali metals and / or alkaline earth metals at the nominal voltage of the sodium ion battery.

[0173] In some embodiments, the inorganic particles include one or more of boehmite γ-AlOOH, aluminum oxide Al2O3, aluminum hydroxide AlOH3, barium sulfate BaSO4, magnesium oxide MgO, magnesium hydroxide MgOH2, calcium oxide CaO, cerium oxide CeO2, zirconium titanate SrTiO3, barium titanate BaTiO3, and magnesium fluoride MgF2.

[0174] In some embodiments, the organic particles include at least one of polystyrene, polyethylene, polyimide, melamine resin, phenolic resin, polypropylene, polyester (e.g., polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate), polyphenylene sulfide, polyaramid, polyamideimide, polyimide, copolymer of butyl acrylate and ethyl methacrylate, and mixtures thereof.

[0175] In some embodiments, the soft-pack battery cell 23 also includes an electrolyte. During the charge and discharge process of the battery cell, active ions are embedded and removed back and forth between the positive electrode sheet and the negative electrode sheet, and the electrolyte plays a role in conducting active ions between the positive electrode sheet and the negative electrode sheet. The embodiment of the present application has no particular restriction on the type of electrolyte, which can be selected according to actual needs. The electrolyte includes an electrolyte salt and a solvent. The types of electrolyte salts and solvents are not specifically limited and can be selected according to actual needs.

[0176] In some embodiments, the electrolyte may also optionally include additives. For example, the additives may include negative electrode film-forming additives, positive electrode film-forming additives, and additives that can improve certain battery properties, such as additives that improve battery overcharge performance, additives that improve battery high temperature performance, and additives that improve battery low temperature power performance.

[0177] For example, the additive includes at least one of a cyclic carbonate compound containing an unsaturated bond, a sulfate compound, a sulfite compound, a sultone compound, a disulfonic acid compound, a nitrile compound, an aromatic compound, an isocyanate compound, a phosphazene compound, an acid anhydride, a cyclic acid anhydride compound, a phosphite compound, a phosphate compound, a borate ester, and a carboxylate compound.

[0178] It can be understood that when the soft-pack battery cell 23 is a lithium iron phosphate battery cell, in the positive electrode material of the soft-pack battery cell 23, the positive electrode active material accounts for 96 parts of the total weight of the positive electrode material, the binder accounts for 1 to 3 parts of the total weight of the positive electrode material (for example, it may include but is not limited to 1, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, 3, etc.), and the conductive agent accounts for 1 to 3 parts of the total weight of the positive electrode material (for example, it may include but is not limited to 1, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, 3, etc.).

[0179] For example, when the soft-pack battery cell 23 is a lithium iron phosphate battery cell, the positive electrode active material is LFP (which may refer to LiFePO4, i.e., lithium iron phosphate), the binder may be PVDF (polyvinylidene fluoride), and the conductive agent may be conductive carbon black, wherein LFP:PVDF:conductive carbon black may be 96:2:2, that is, the total weight of the positive electrode active material is 100 parts, LFP accounts for 96 parts, PVDF accounts for 2 parts, and conductive carbon black also accounts for 2 parts. The weight unit of the positive electrode active material may be grams.

[0180] When the soft-pack battery cell 23 is a ternary battery cell, in the positive electrode material of the soft-pack battery cell 23, the positive electrode active material accounts for 96 parts of the total weight of the positive electrode material, the binder accounts for 2-3 parts of the total weight of the positive electrode material (for example, including but not limited to 2, 2.2, 2.5, 2.8, 3, etc.), and the conductive agent accounts for 1-2 parts of the total weight of the positive electrode material (for example, including but not limited to 1, 1.2, 1.5, 1.8, 2, etc.). Among them, the ternary battery cell can be but not limited to nickel cobalt manganese lithium oxide system, nickel cobalt aluminum oxide lithium oxide system, etc.

[0181] For example, the ternary material of the ternary battery cell can be eight series LiNi 0.8 Co 0.1 Mn 0.1 O2, the weight ratio of the positive electrode active material, binder and conductive agent is 96:2.5:1.5, that is, the total weight of the positive electrode material is divided into 100 parts, eight series LiNi 0.8 Co 0.1 Mn 0.1 O2 accounts for 96 parts, the binder accounts for 2.5 parts, and the conductive agent accounts for 1.5 parts.

[0182] In some embodiments, the soft-pack battery cell 23 is a ternary battery cell, and the shell walls of the first shell 21 and the second shell 22 for limiting the movement of the soft-pack battery cell 23 therein in the opposite direction in the second direction are respectively provided with a pressure relief portion 20. For example, the first limiting shell wall 21b described above is provided with a pressure relief portion 20, and the second limiting shell wall 22b is provided with a pressure relief portion 20.

[0183] In the above technical solution, when the ternary battery cell undergoes thermal runaway expansion and exhaust pressure relief, the pressure relief unit 20 can guide the exhausted gas to directional pressure relief, thereby reducing the risk of gas chaos affecting the surrounding ternary battery cells, and also reducing the risk of serious thermal runaway of the battery pack 2 composed of the ternary battery cells, which is beneficial to the thermal runaway management of the battery pack 2 and improves the reliability of the battery pack 2 composed of the ternary battery cells.

[0184] In some embodiments, the pressure relief portion 20 is configured as a pressure relief hole; or, the pressure relief portion 20 is configured as a notch; or, the pressure relief portion 20 is configured as a weakened portion. Thus, more options can be provided for the design of the pressure relief portion 20 to meet different usage requirements.

[0185] The following takes the pressure relief portion 20 on the first housing 21 as an example:

[0186] The weakened portion refers to a local specific area of ​​the first shell 21, which has a lower strength than other areas due to the combined effects of material properties, geometric shape, size thickness or other factors. When the soft-pack battery cell 23 is working normally, the weakened portion can maintain structural integrity, but when subjected to external or internal forces exceeding a certain limit (such as a preset pressure), the weakened portion deforms, ruptures or fails earlier than other areas of the first shell 21, thereby achieving communication between the inside of the first U-shaped installation cavity 21a and the external space to achieve pressure relief.

[0187] In some examples, the weakened portion may be made of a material with lower strength than other parts of the first shell 21. In some examples, the thickness of the weakened portion may be thinner than the thickness of other areas of the first shell 21. In some embodiments, the weakened portion may be formed with a weakened hole or a weakened groove.

[0188] The pressure relief portion 20 is notched to produce stress concentration. When the pressure in the first U-shaped mounting cavity 21a increases, stress will preferentially accumulate in the notched or etched portion, so that the area can accurately rupture or deform under a preset pressure, thereby achieving pressure relief. As a result, the rupture direction of the pressure relief portion 20 can be guided, the pressure relief area of ​​the pressure relief portion 20 after rupture can be increased, and the speed and efficiency of pressure relief can be improved. It should be noted that by precisely controlling the depth, width and shape of the notch, the strength of the pressure relief portion 20 can be adjusted, and the pressure threshold of pressure relief can be flexibly set according to different soft-pack battery cells 23.

[0189] The pressure relief portion 20 may also be a through hole (pressure relief hole) that passes through the first shell 21 along the thickness direction of the first shell 21. It should be noted that the through hole connects the inner and outer spaces of the first U-shaped mounting cavity 21a. By controlling the size and number of the through holes, the pressure relief pressure threshold can be accurately set. Since the total cross-sectional area of ​​the through holes of the pressure relief portion 20 is constant, a stable pressure relief rate can be guaranteed.

[0190] The pressure relief portion 20 may also be a notch formed by being recessed inwardly along the circumferential edge of the first shell 21 , and the area of ​​the notch may be determined according to the size of the preset pressure relief pressure, thereby ensuring a stable pressure relief rate.

[0191] In a second aspect, an embodiment of the present application provides an electric device 1000 , comprising the battery device 100 of any of the above embodiments.

[0192] In the above technical solution, since the battery device 100 has high reliability, the use of the battery device 100 can improve the power consumption reliability of the power consumption device 1000.

[0193] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0194] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A battery device, characterized in that: include: A battery pack includes a first shell, a second shell and a plurality of soft-pack battery cells, wherein the first shell and the second shell are arranged in sequence along a first direction and are connected to each other, the first shell has a first U-shaped mounting cavity, the second shell has a second U-shaped mounting cavity, a plurality of the soft-pack battery cells are respectively arranged in the first U-shaped mounting cavity and the second U-shaped mounting cavity, and are used to limit the movement of the soft-pack battery cells therein from two opposite directions in a second direction, and the second direction is perpendicular to the first direction.

2. The battery device according to claim 1, characterized in that: The portion of the first shell connected to the second shell extends into the second U-shaped installation cavity, and the portion of the second shell connected to the first shell extends into the first U-shaped installation cavity.

3. The battery device according to claim 1, characterized in that: A reinforcement protrusion is provided on the outer surface of at least one of the first shell and the second shell.

4. The battery device according to claim 1, characterized in that: Also includes: An elastic pad is sandwiched between the first shell and the second shell.

5. The battery device according to claim 4, characterized in that: The elastic pad is a heat insulating member.

6. The battery device according to claim 1, characterized in that: The first shell includes a first shell wall, a second shell wall and a third shell wall, the first shell wall and the second shell wall are spaced apart along the first direction, and the third shell wall is connected to one end of the first shell wall and the second shell wall in the second direction to close one end of the first U-shaped mounting cavity in the second direction and to limit the movement of the soft-pack battery cell inside. The second shell body includes a fourth shell wall, a fifth shell wall and a sixth shell wall, the fourth shell wall is adjacent to and fixedly connected to the second shell wall, and the fourth shell wall and the fifth shell wall are spaced apart along the first direction, and the sixth shell wall is connected to the other end of the fourth shell wall and the fifth shell wall in the second direction to close one end of the second U-shaped mounting cavity in the second direction and to limit the movement of the soft-pack battery cell inside.

7. The battery device according to claim 6, characterized in that: The fourth shell wall is located on a side of the second shell wall away from the first shell wall; or, The fourth shell wall is located on a side of the second shell wall facing the first shell wall.

8. The battery device according to claim 6, characterized in that: The fourth shell wall is located on the side of the second shell wall facing away from the first shell wall, the free end of the second shell wall stops at the connection position between the fourth shell wall and the sixth shell wall, and the free end of the fourth shell wall stops at the connection position between the second shell wall and the third shell wall.

9. The battery device according to claim 6, characterized in that: Each of the first shell wall, the second shell wall, the fourth shell wall and the fifth shell wall is configured to include a first plate portion and a second plate portion that are arranged and connected along the second direction, the second plate portion and the tab of the soft-pack battery cell are staggered in the second direction, and the first plate portion and the tab are opposite to each other along the first direction. In the third direction, the length of the first plate portion is greater than the length of the second plate portion, and the electrode tab extends between one end of the length of the first plate portion and one end of the length of the second plate portion.

10. The battery device according to claim 6, characterized in that: At least one outer surface of the first shell wall, the third shell wall, the fifth shell wall and the sixth shell wall is provided with a reinforcement protrusion; and / or, At least one of the mutually opposite side surfaces of the second shell wall and the fourth shell wall is provided with a reinforcing protrusion.

11. The battery device according to claim 10, characterized in that: The reinforcing protrusions are configured as ribs or convex points.

12. The battery device according to claim 1, characterized in that: The first shell and the second shell are an integral part or separate parts.

13. The battery device according to claim 1, characterized in that: There are a plurality of the first shells and a plurality of the second shells, respectively, and the plurality of the first shells and the plurality of the second shells are alternately arranged one by one along the first direction.

14. The battery device according to claim 1, characterized in that: Also includes: The box body has a receiving cavity, and the battery pack is arranged in the receiving cavity. The closed end of the first U-shaped installation cavity in the second direction is fixedly connected to the box body, and the closed end of the second U-shaped installation cavity in the second direction is fixedly connected to the box body; and / or, The battery device also includes a first connecting plate and a second connecting plate, the first connecting plate closes the open end of the first U-shaped mounting cavity in the second direction, the second connecting plate closes the open end of the second U-shaped mounting cavity in the second direction, the first shell is fixedly connected to the box body through the first connecting plate, and the second shell is fixedly connected to the box body through the second connecting plate.

15. The battery device according to any one of claims 1 to 14, characterized in that: The battery device further includes at least one of a first heat exchange member and a second heat exchange member, wherein the at least one of the first heat exchange member and the second heat exchange member is used for heat exchange with the soft pack battery cell. The first heat exchange member is disposed between the first shell and the second shell, and the second heat exchange member is disposed between the battery pack and the box of the battery device.

16. The battery device according to any one of claims 1 to 14, characterized in that: The soft-pack battery cell is any one of a lithium iron phosphate battery cell, a ternary battery cell and a solid-state battery cell.

17. The battery device according to claim 16, characterized in that: The soft-pack battery cell is a lithium iron phosphate battery cell, and in the positive electrode material of the soft-pack battery cell, the usage ratio of the positive electrode active material, the binder, and the conductive agent is 96: (1-3): (1-3); the soft-pack battery cell is a ternary battery cell, and in the positive electrode material of the soft-pack battery cell, the usage ratio of the positive electrode active material, the binder, and the conductive agent is 96: (2-3): (1-2).

18. The battery device according to claim 16, characterized in that: The soft-pack battery cell is a ternary battery cell, and the shell walls of the first shell and the second shell for limiting the movement of the soft-pack battery cell therein from opposite directions in the second direction are respectively provided with pressure relief portions.

19. The battery device according to claim 18, characterized in that: The pressure relief portion is configured as a pressure relief hole; or, the pressure relief portion is configured as a notch; or, the pressure relief portion is configured as a weakened portion.

20. An electrical device, characterized in that: Comprising a battery device according to any one of claims 1-19.

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