Battery device and electric equipment

Abstract

The utility model discloses a battery device and electric equipment, the battery device comprises a plurality of soft package battery cells and a heat dissipation piece, the plurality of soft package battery cells are arranged along a first direction; and the heat dissipation piece is arranged between the two adjacent soft package battery cells. In the battery device provided by the embodiment of the invention, the heat dissipation piece is arranged between the two adjacent soft package battery cells, and the heat dissipation piece can quickly transfer and dissipate heat of the soft package battery cells to the surrounding environment, so that the temperature rise of the soft package battery cells is reduced, and the working performance of the soft package battery cells is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery device and electrical equipment. Background Art

[0002] Batteries are widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric vehicles, as well as in military equipment and aerospace. Batteries can be broadly categorized into soft-pack batteries and hard-shell batteries based on the hardness or softness of their outer shells. Soft-pack batteries offer advantages such as high mass / volume energy density and improved safety, leading to their increasing application. During charge and discharge, soft-pack batteries inevitably generate heat. High temperatures can affect their performance. Therefore, reducing the temperature rise of soft-pack batteries remains a challenging technical challenge. Utility Model Content

[0003] The utility model provides a battery device and electrical equipment, which can reduce the temperature rise of soft-pack batteries.

[0004] The battery device of the embodiment of the present invention includes a plurality of soft-pack battery cells and a heat sink. The plurality of soft-pack battery cells are arranged along a first direction; the heat sink is provided between two adjacent soft-pack battery cells.

[0005] In the battery device of the above embodiment, the heat sink is arranged between two adjacent soft-pack battery cells. The heat sink can quickly transfer the heat of the soft-pack battery cells to the surrounding environment, thereby reducing the temperature rise of the soft-pack battery cells and improving the working performance of the soft-pack battery cells.

[0006] In some embodiments of the present invention, the soft-pack battery cell includes a first outer surface, which is the largest surface of the soft-pack battery cell. The first outer surfaces of multiple soft-pack battery cells are arranged along the first direction, and the heat dissipation element is arranged between the first outer surfaces of two adjacent soft-pack battery cells.

[0007] In the above technical solution, since the first outer surface is the largest surface of the soft-pack battery cell, the heat sink is arranged between the first outer surfaces of two adjacent soft-pack battery cells, so that the heat transfer efficiency between the heat sink and the soft-pack battery cell is higher, and the temperature rise of the soft-pack battery can be reduced more quickly.

[0008] In some embodiments of the present invention, a projection of the heat dissipation element in the first direction is located within the first outer surface of the soft-pack battery cell.

[0009] In the above technical solution, the size of the heat sink is smaller than that of the soft-pack battery cell. When the heat sink satisfies the heat transfer requirements, the heat sink occupies less space in the battery device, thereby improving the energy density of the battery device.

[0010] In some embodiments of the present invention, the surface of the heat sink facing the soft-pack battery core is a plane.

[0011] In the above technical solution, the surface of the heat sink facing the soft-pack battery cell is flat, so that when the heat sink contacts the soft-pack battery cell, the contact area between the heat sink and the soft-pack battery cell can be increased, thereby improving the heat transfer efficiency between the heat sink and the soft-pack battery cell.

[0012] In some embodiments of the present invention, the heat sink is spaced apart from the soft-pack battery cell.

[0013] In the above technical solution, since the soft-pack battery cell will inevitably expand and deform during use, the heat sink is arranged at a distance from the soft-pack battery cell, which can provide a certain space for the expansion and deformation of the soft-pack battery cell, reduce the stress of the soft-pack battery cell, and improve the working performance of the soft-pack battery cell.

[0014] In some embodiments of the present invention, the heat dissipation element is a solid structural element.

[0015] In the above technical solution, the solid heat sink has a high heat conduction efficiency, which can improve the efficiency of the heat sink in transferring heat to the surrounding environment.

[0016] In some embodiments of the present invention, the heat sink is a plate-shaped member of uniform thickness, and the thickness direction of the heat sink is the same as the first direction.

[0017] In the above technical solution, the heat sinks of equal thickness make the heat conduction efficiency of each position of the heat sink roughly the same, which can improve the consistency of heat transfer of the heat sink.

[0018] In some embodiments of the present invention, the heat sink is a metal member.

[0019] In the above technical solution, the metal heat sink has good thermal conductivity, which can improve the heat conduction efficiency of the heat sink. In addition, the heat sink is strong, which can support the soft-pack battery cell when it is impacted, reduce the degree of deformation of the soft-pack battery cell, and improve the stability of the soft-pack battery cell.

[0020] In some embodiments of the present invention, the thickness of the heat sink is D1, 0.2 mm ≤ D1 ≤ 2 mm.

[0021] In the above technical solution, when the thickness of the heat sink is within the above range, the heat sink is easy to prepare, has a suitable volume, occupies a small space, can improve the energy density of the battery device, and has a high thermal conductivity efficiency.

[0022] In some embodiments of the present invention, the battery device includes a support member, which is arranged at an edge of the heat sink and abuts against the soft-pack battery cell.

[0023] In the above technical solution, the support member can provide support for the soft-pack battery cell and improve the position stability of the soft-pack battery cell.

[0024] In some embodiments of the present invention, the support member surrounds the heat dissipation member.

[0025] In the above technical solution, the support member can limit the position of the heat sink, improve the position stability of the heat sink, and thus improve the heat dissipation effect of the heat sink on the soft-pack battery cell. In addition, the support member and the soft-pack battery cell have more abutment points, which improves the support effect of the support member on the soft-pack battery cell.

[0026] In some embodiments of the present invention, the soft-pack battery cell includes a first outer surface, which is the largest surface of the soft-pack battery cell. The first outer surface of the soft-pack battery cell is arranged along the first direction. The heat dissipation member is arranged between the first outer surfaces of two adjacent soft-pack battery cells, and the outer contour area of ​​the support member is smaller than the area of ​​the first outer surface of the soft-pack battery cell.

[0027] In the above technical solution, the outer contour area of ​​the support member is smaller than the area of ​​the first outer surface of the soft-pack battery cell. When the support member can support the soft-pack battery cell, the support member occupies less space in the battery device, thereby improving the energy density of the battery device.

[0028] In some embodiments of the present invention, the support member is combined with a side surface of the heat dissipation member.

[0029] In the above technical solution, the side surfaces of the support member and the heat sink are combined, which not only allows the support member and the heat sink to form a whole, thereby reducing the number of parts in the battery device assembly process and improving the assembly efficiency of the battery device, but also allows the heat sink to maintain a stable position under the connection of the support member, thereby improving the heat dissipation effect of the heat sink on the soft-pack battery cell.

[0030] In some embodiments of the present invention, along the first direction, the thickness of the support member is greater than the thickness of the heat dissipation member.

[0031] In the above technical solution, the support member enables at least one side of the heat sink to be spaced apart from the corresponding soft-pack battery cell, thereby providing space for the expansion and deformation of the soft-pack battery cell.

[0032] In some embodiments of the present invention, along the first direction, a thickness ratio of the support member to the soft-pack battery cell is less than 10%.

[0033] In the above technical solution, the thickness ratio of the support member to the soft-pack battery cell is small, that is, the space occupied by the support member is small and the space occupied by the soft-pack battery cell is large, which can improve the energy density of the battery device.

[0034] In some embodiments of the present invention, the support member is made of polypropylene material.

[0035] In the above technical solution, the support member has good insulation performance, which can improve the stability of the battery device. In addition, the chemical properties of the support member are relatively stable, which can increase the life of the battery device.

[0036] In some embodiments of the present invention, the support member is a deformable elastic member.

[0037] In the above technical solution, the support member can be deformed, and during the process of expansion and deformation of the soft-pack battery cell, the stress of the soft-pack battery cell can be reduced, thereby improving the use stability of the soft-pack battery cell.

[0038] In some embodiments of the present invention, the battery device includes a water-cooling plate, and the soft-pack battery cell is thermally connected to the water-cooling plate.

[0039] In the above technical solution, the water cooling plate can cool the soft-pack battery cells and reduce the temperature rise of the soft-pack battery cells.

[0040] In some embodiments of the present invention, the soft-pack battery cell rests on the water-cooling plate along a second direction, and the first direction intersects with the second direction.

[0041] In the above technical solution, the soft-pack battery cell is supported on the water-cooling plate, so that the soft-pack battery cell is close to the water-cooling plate, which can improve the heat exchange efficiency between the soft-pack battery cell and the water-cooling plate, and thus can quickly reduce the temperature rise of the soft-pack battery cell.

[0042] In some embodiments of the present invention, a heat conducting member is provided between the water-cooling plate and the soft-pack battery cell, and the heat conducting member connects the soft-pack battery cell and the water-cooling plate.

[0043] In the above technical solution, the heat conductive member can improve the heat exchange efficiency between the water-cooling plate and the soft-pack battery cell, which is beneficial for the water-cooling plate to cool the soft-pack battery cell.

[0044] According to some embodiments of the present invention, optionally, 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.

[0045] In the above technical solution, the use of the above-mentioned soft-pack cells can provide more options for battery device design to meet different usage requirements. Among them, the soft-pack cells are lithium iron phosphate battery cells, which have the advantages of high reliability, long cycle life, light weight, large capacity, and low internal resistance; the soft-pack cells are ternary battery cells, which have the advantages of high energy density and good electrochemical performance; and the soft-pack cells are solid-state battery cells, which have the advantages of high energy density, high reliability, light weight, and good high and low temperature performance.

[0046] According to some embodiments of the present invention, optionally, 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); and / or, 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).

[0047] 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 material means that more substances capable of undergoing electrochemical reactions can be accommodated within 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 application scenarios with certain requirements for energy density. The use of the binder and conductive agent in the above range 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, due to the relatively complex structure and surface properties of the ternary material itself, the use of the positive electrode active material, binder, and conductive agent in the above-mentioned dosage ratio 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, reducing the risk of active material shedding and electrode pulverization during charging and discharging, and extending the cycle life of the battery device.

[0048] An electrical device comprising the battery device described in any one of the above embodiments.

[0049] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. The same reference numerals are used throughout the accompanying drawings to denote the same components. In the accompanying drawings:

[0051] Figure 1 A schematic structural diagram of a vehicle according to some embodiments of the present invention;

[0052] Figure 2 Schematic diagram of a three-dimensional exploded view of a battery device according to some embodiments of the present invention;

[0053] Figure 3 This is one of the partial schematic diagrams of a battery device according to some embodiments of the present invention;

[0054] Figure 4 This is a second partial schematic diagram of a battery device according to some embodiments of the present invention;

[0055] Figure 5 A partially exploded schematic diagram of a battery device according to some embodiments of the present invention;

[0056] Figure 6 Schematic diagram of a portion of the structure of a battery device according to some embodiments of the present invention.

[0057] Description of reference numerals:

[0058] 100-battery device; 110-housing; 10-soft-pack battery cell; 11-first outer surface; 12-second outer surface; 20-heat sink; 21-side; 30-support; 40-water cooling plate; 50-heat conducting element; 1000-vehicle; 200-controller; 300-motor. DETAILED DESCRIPTION

[0059] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0060] Unless otherwise defined, all technical and scientific terms used in this utility model have the same meanings as those commonly understood by those skilled in the art to which this utility model belongs; the terms used in the specification of this utility model are only for the purpose of describing specific embodiments and are not intended to limit this utility model; the terms "including" and "having" and any variations thereof in the specification and claims of this utility model and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this utility model or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0061] Reference to an "embodiment" in this disclosure means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the disclosure. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments.

[0062] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this utility model based on specific circumstances.

[0063] In this application, the term "and / or" simply describes a relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, and B exists alone. Furthermore, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0064] In the embodiments of the present invention, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of the present invention, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are for illustrative purposes only and do not constitute any limitation on the present invention.

[0065] The term “plurality” used in this invention refers to two or more (including two).

[0066] In the embodiments of the present invention, unless otherwise specified, all embodiments and optional embodiments of the present invention can be combined with each other to form a new technical solution.

[0067] In the embodiments of the present invention, unless otherwise specified, all technical features and optional technical features of the present invention can be combined with each other to form a new technical solution.

[0068] Batteries are widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric vehicles, as well as in military equipment and aerospace. Batteries can be broadly categorized into soft-pack batteries and hard-pack batteries based on the hardness or softness of their outer shells. Soft-pack batteries offer advantages such as high mass / volume energy density and improved safety, leading to their increasing application. During charge and discharge, soft-pack batteries inevitably generate heat. High temperatures can affect their performance.

[0069] For example, after a soft-pack battery cell experiences thermal runaway, due to the poor thermal conductivity of the soft-pack battery cell itself, two adjacent soft-pack battery cells come into contact with each other, making it difficult for the heat generated by the soft-pack battery cell in thermal runaway to dissipate quickly, causing the temperature of the adjacent soft-pack battery cells to rise rapidly, increasing the risk of thermal runaway.

[0070] To this end, the present invention provides a battery device, which includes a plurality of soft-pack battery cells and a heat sink, wherein the plurality of soft-pack battery cells are arranged along a first direction; and the heat sink is disposed between two adjacent soft-pack battery cells.

[0071] In the battery device of the above embodiment, the heat sink is arranged between two adjacent soft-pack battery cells. The heat sink can quickly transfer the heat of the soft-pack battery cells to the surrounding environment, thereby reducing the temperature rise of the soft-pack battery cells and improving the working performance of the soft-pack battery cells.

[0072] The present invention provides an electrical device that uses a battery device as a power source. The electrical device may be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery-powered vehicle, an electric car, a ship, a spacecraft, and the like. The electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, and the like.

[0073] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present invention.

[0074] Please refer to Figure 1, the vehicle 1000 may be a new energy vehicle, which may be a pure electric vehicle, a hybrid electric vehicle, or an extended-range vehicle, etc. Furthermore, the vehicle 1000 may be a commercial vehicle. A battery device 100 is provided inside the vehicle 1000, and the battery device 100 may be provided at the bottom, head, or tail of the vehicle 1000. The battery device 100 may be used to power the vehicle 1000. For example, the battery device 100 may serve as an operating power source for the vehicle 1000. The vehicle 1000 may further include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to power the motor 300, for example, to meet the power requirements for starting, navigating, and driving the vehicle 1000.

[0075] In some embodiments of the present invention, the battery device 100 can serve not only as an operating power source for the vehicle 1000 , but also as a driving power source for the vehicle 1000 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000 .

[0076] See also Figure 2 In an embodiment of the present invention, a battery apparatus 100 may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include a plurality of soft-pack battery cells 10, which are connected in series, in parallel, or in mixed connection via a busbar. For example, a battery cell assembly is typically formed by arranging a plurality of soft-pack battery cells 10; a battery cell assembly may be a battery module, which is formed by arranging and fixing a plurality of soft-pack battery cells 10 to form an independent module. As an example, a battery module may be formed by bundling a plurality of soft-pack battery cells 10 by cable ties.

[0077] The battery device 100 may be a battery pack, which includes a housing 110 and one or more battery cell assemblies housed in the housing 110. The battery cell assemblies may be battery modules, which may be housed in the housing 110 by securing the battery modules therein. Alternatively, the battery cell assemblies may be housed in the housing 110 by directly securing multiple soft-pack battery cells 10 therein.

[0078] In an embodiment of the present invention, the housing 110 may include a first housing and a second housing. The first housing and the second housing are fastened together to form a closed space inside the housing 110 to accommodate the battery cell assembly. The closed space here refers to covering or closing, which can be sealed or unsealed. The first housing may be a top cover or a bottom plate. For example, the housing 110 may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, so that a closed space is formed inside the housing 110 to accommodate the battery cell assembly.

[0079] In an embodiment of the present invention, the box 110 may serve as part of the chassis structure of the vehicle 1000. For example, a portion of the box 110 may become at least a portion of the floor of the vehicle 1000, or a portion of the box 110 may become at least a portion of the crossbeam and longitudinal beam of the vehicle.

[0080] In the embodiment of the present invention, the soft-pack battery cell 10 may be a secondary battery. A secondary battery is a soft-pack battery cell 10 that can be recharged to activate the active material after discharge and continue to be used. The soft-pack battery cell 10 may 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-metal hydride battery, a nickel-cadmium battery, a lead-acid battery, or the like, and the embodiment of the present invention is not limited thereto. The soft-pack battery cell 10 may be flat, rectangular, or in other shapes, and the embodiment of the present invention is not limited thereto.

[0081] See also Figure 3-Figure 5 The battery device 100 of the embodiment of the present invention includes a plurality of soft-pack battery cells 10 and a heat sink 20 . The plurality of soft-pack battery cells 10 are arranged along a first direction X. The heat sink 20 is disposed between two adjacent soft-pack battery cells 10 .

[0082] Specifically, the soft-pack cell 10 may have a flexible housing. The flexible housing of the soft-pack cell 10 has good flexibility and may be formed into a pouch shape. The electrode assembly of the soft-pack cell 10 is accommodated in the flexible housing, making the soft-pack cell 10 a soft-pack battery. For example, the flexible housing may be an aluminum-plastic film.

[0083] The electrode assembly of the soft-pack battery cell 10 can be a wound electrode assembly or a stacked electrode assembly. The electrode assembly can include electrode sheets and tabs. The electrode assembly can be formed by winding electrode sheets or stacking electrode sheets.

[0084] The plurality of soft-packed battery cells 10 may be of the same size, shape, and other parameters, or at least two of the soft-packed battery cells 10 may have different parameters. The first direction X may be a horizontal direction when the battery device 100 is in normal use.

[0085] The heat sink 20 has excellent thermal conductivity, which is superior to that of the pouch cell 10. Heat generated by the pouch cell 10 can be transferred to the heat sink 20, which in turn transfers the heat to the surrounding environment. The "surrounding environment" referred to here can include any material that can exchange heat with the heat sink 20, such as the pouch cell 10 or the atmosphere.

[0086] It should be noted that the number of heat sinks 20 can be one or more. When the number of heat sinks 20 is multiple, a heat sink 20 can be set between any two adjacent soft-pack battery cells 10, or between two partially adjacent soft-pack battery cells 10.

[0087] Therefore, in the battery device 100 of the above embodiment, the heat sink 20 is arranged between two adjacent soft-pack battery cells 10. The heat sink 20 can quickly transfer and dissipate the heat of the soft-pack battery cells 10 to the surrounding environment, thereby reducing the temperature rise of the soft-pack battery cells 10 and improving the working performance of the soft-pack battery cells 10.

[0088] For example, among multiple soft-pack battery cells 10, if one of the soft-pack battery cells 10 experiences thermal runaway and generates a large amount of heat, the heat sink 20 close to the thermal runaway can transfer the heat evenly to other soft-pack battery cells 10, thereby reducing the risk of thermal runaway in another soft-pack battery cell 10 adjacent to the thermal runaway soft-pack battery cell 10.

[0089] See also Figure 3 In some embodiments of the present invention, the soft-pack battery cell 10 includes a first outer surface 11, which is the largest surface of the soft-pack battery cell 10. The first outer surfaces 11 of the multiple soft-pack battery cells 10 are arranged along the first direction X, and the heat dissipation member 20 is arranged between the first outer surfaces 11 of two adjacent soft-pack battery cells 10.

[0090] Specifically, the soft-pack battery cell 10 may be flat and may further include a second outer surface 12 connected to the first outer surface 11, wherein the area of ​​the second outer surface 12 is smaller than the area of ​​the first outer surface 11. The first outer surface 11 is substantially perpendicular to the first direction X. For example, the angle between the normal of the first outer surface 11 and the first direction X may be less than 30°.

[0091] It can be understood that when the first outer surface 11 of the soft-pack battery cell 10 is the largest surface, most of the heat generated by the soft-pack battery cell 10 is also dissipated through the first outer surface 11 of the soft-pack battery cell 10, and the heat of the soft-pack battery cell 10 is mainly concentrated on the first outer surface 11. Therefore, the heat dissipation element 20 is disposed between the first outer surfaces 11 of two adjacent soft-pack battery cells 10, so that the heat transfer efficiency between the heat dissipation element 20 and the soft-pack battery cell 10 is higher, and the temperature rise of the soft-pack battery can be reduced more quickly.

[0092] See also Figure 3 In some embodiments of the present invention, the projection of the heat sink 20 in the first direction X is within the first outer surface 11 of the soft-pack battery cell 10. In other words, the outer contour of the first outer surface 11 can surround the outer contour of the projection of the heat sink 20 in the first direction X. For example, the outer contour of the first outer surface 11 can be a first square, and the outer contour of the projection of the heat sink 20 in the first direction X can be a second square, with the first direction X being within the second square.

[0093] Therefore, the heat sink 20 is retracted relative to the outline of the soft-pack battery cell 10 and does not protrude from the soft-pack battery cell 10 , which reduces the probability of interference with surrounding components and also makes the soft-pack battery cell 10 occupy a larger space of the entire battery device 100 .

[0094] Thus, in the above technical solution, the size of the heat sink 20 is smaller than that of the soft-pack battery cell 10 . When the heat sink 20 satisfies the heat transfer requirements, the heat sink 20 occupies a smaller space in the battery device 100 , thereby improving the energy density of the battery device 100 .

[0095] In some embodiments of the present invention, the surface of the heat sink 20 facing the soft-pack battery core 10 is a plane.

[0096] In the above technical solution, the surface of the heat sink 20 facing the soft-pack battery cell 10 is flat. This increases the contact area between the heat sink 20 and the soft-pack battery cell, improving the heat transfer efficiency between the heat sink 20 and the soft-pack battery cell. Furthermore, the heat sink 20 is easy to manufacture, which can reduce the manufacturing cost of the heat sink 20.

[0097] See also Figure 3 In some embodiments of the present invention, the heat sink 20 is spaced apart from the soft-pack battery cell 10. In other words, a gap exists between the heat sink 20 and the soft-pack battery cell 10. It should be noted that the gap between the heat sink 20 and the soft-pack battery cell 10 is formed when the soft-pack battery cell 10 is not deformed or has a low degree of deformation. When the soft-pack battery cell 10 is significantly deformed, the soft-pack battery cell 10 may contact the heat sink 20.

[0098] In the above technical solution, since the soft-pack battery cell 10 will inevitably expand and deform during use, the heat sink 20 is spaced apart from the soft-pack battery cell 10, which can provide a certain space for the expansion and deformation of the soft-pack battery cell 10, reduce the stress of the soft-pack battery cell 10, and improve the working performance of the soft-pack battery cell 10.

[0099] In some embodiments of the present invention, the heat sink 20 is a solid structural member. In other words, the heat sink 20 has no internal holes or other structures, so that the thermal conductivity of each part of the heat sink 20 is basically the same. Therefore, in the above technical solution, the solid heat sink 20 has a higher thermal conductivity efficiency, which can improve the efficiency of heat transfer from the heat sink 20 to the surrounding environment.

[0100] See also Figure 3 In some embodiments of the present invention, the heat sink 20 is a plate-shaped member of uniform thickness, and the thickness direction of the heat sink 20 is the same as the first direction X. In other words, along the first direction X, the thickness of the heat sink 20 is uniform everywhere.

[0101] In the above technical solution, the heat sink 20 of uniform thickness makes the heat conduction efficiency of each position of the heat sink 20 approximately uniform, which can improve the consistency of heat transfer of the heat sink 20.

[0102] In some embodiments of the present invention, the heat sink 20 is a metal member. For example, the heat sink 20 can be made of aluminum, steel, or copper. In the above technical solution, the metal heat sink 20 has good thermal conductivity, which can improve the thermal efficiency of the heat sink 20. In addition, the heat sink 20 is relatively strong, which can support the soft-pack battery cell 10 when it is impacted, reduce the degree of deformation of the soft-pack battery cell 10, and improve the stability of the soft-pack battery cell 10.

[0103] See also Figure 3 In some embodiments of the present invention, the thickness D1 of the heat sink 20 is 0.2 mm ≤ D1 ≤ 2 mm. For example, the thickness D1 of the heat sink 20 can be 0.2 mm, 0.3 mm, 0.8 mm, 1.5 mm, 2 mm, etc.

[0104] In the above technical solution, the thickness D1 of the heat sink 20 is greater than or equal to 0.2 mm, making the heat sink 20 easy to prepare. In addition, the thickness of the heat sink 20 is less than or equal to 2 mm, making the volume of the heat sink 20 appropriate and occupying less space, which can improve the energy density of the battery device 100 and has a higher thermal conductivity efficiency.

[0105] See also Figure 3-Figure 5 In some embodiments of the present invention, the battery device 100 includes a support member 30, which is disposed at an edge of the heat sink 20 and abuts against the soft-pack battery cells 10. Specifically, the support member 30 can be disposed at one edge of the heat sink 20 or at all edges of the heat sink 20. The support member 30 connects two adjacent soft-pack battery cells 10 so that the adjacent soft-pack battery cells 10 do not move relative to each other.

[0106] In the above technical solution, the support member 30 can provide support for the soft-pack battery cell 10 and improve the position stability of the soft-pack battery cell 10 .

[0107] In some embodiments of the present invention, the support member 30 surrounds the heat sink 20. Specifically, the support member 30 may be frame-shaped, extending along the circumference of the heat sink 20, and connected to all edge positions of the support member 30.

[0108] In the above technical solution, the support member 30 can limit the heat sink 20, improve the positional stability of the heat sink 20, and further improve the heat dissipation effect of the heat sink 20 on the soft-pack battery cell 10. In addition, the support member 30 and the soft-pack battery cell 10 have more abutment points, which improves the support effect of the support member 30 on the soft-pack battery cell 10.

[0109] See also Figure 3-Figure 5 In some embodiments of the present invention, the outer contour area of ​​the support member 30 is smaller than the area of ​​the first outer surface 11 of the soft-pack battery cell 10 .

[0110] Specifically, the outer contour area of ​​the support member 30 refers to the area enclosed by the outer contour of the projection of the support member 30 along the first direction X. The outer contour area of ​​the support member 30 is smaller than the area of ​​the first outer surface 11 of the soft-pack battery cell 10. That is, the projection of the support member 30 along the first direction X onto the first outer surface 11 is located within the first outer surface 11. For example, the support member 30 has four outer edges, at least one of which is retracted relative to the outer edge of the soft-pack battery cell 10.

[0111] In the above technical solution, the outer contour area of ​​the support member 30 is smaller than the area of ​​the first outer surface 11 of the soft-pack battery cell 10. When the support member 30 can support the soft-pack battery cell 10, the support member 30 occupies less space in the battery device 100, thereby improving the energy density of the battery device 100.

[0112] See also Figure 3-Figure 5 In some embodiments of the present invention, the support member 30 is coupled to the side surface 21 of the heat sink 20. In other words, the support member 30 and the heat sink 20 are connected to form a single unit. For example, the support member 30 and the heat sink 20 can be coupled together by bonding, interlocking, in-mold injection molding, or other processes. The side surface 21 of the heat sink 20 is a surface of the heat sink 20 that is parallel to the first direction X.

[0113] In the above technical solution, the support member 30 is combined with the side surface 21 of the heat sink 20, which not only allows the support member 30 and the heat sink 20 to form a whole, thereby reducing the number of parts in the assembly process of the battery device 100 and improving the assembly efficiency of the battery device 100, but also allows the heat sink 20 to maintain a stable position under the connection of the support member 30, thereby improving the heat dissipation effect of the heat sink 20 on the soft-pack battery cell 10.

[0114] See also Figure 3 In some embodiments of the present invention, the thickness of the support member 30 is greater than the thickness of the heat sink 20 along the first direction X. Thus, because the support member 30 is disposed at the edge of the heat sink 20, when the thickness of the support member 30 is greater than that of the heat sink 20, at least one side of the support member 30 along the first direction X protrudes beyond the heat sink 20 and abuts against the soft-pack battery cell 10. Thus, in the above-described technical solution, the support member 30 spaced at least one side of the heat sink 20 from the corresponding soft-pack battery cell 10, providing space for the soft-pack battery cell 10 to expand and deform.

[0115] See also Figure 3 In some embodiments of the present invention, along the first direction X, the ratio of the thickness of the support member 30 to the thickness of the soft-pack battery cell 10 is less than 10%. For example, the thickness of the support member 30 is D2, the thickness of the soft-pack battery cell 10 is D3, and D2 / D3 is less than 10%. For example, D2 / D3 can be 1%, 2%, 5%, 6%, 9%, etc.

[0116] In the above technical solution, the thickness ratio of the support member 30 to the soft-pack battery cell 10 is small, that is, the support member 30 occupies a smaller space and the soft-pack battery cell 10 occupies a larger space, which can improve the energy density of the battery device 100.

[0117] In some embodiments of the present invention, the support member 30 is made of a polypropylene material, which is a type of polymer material formed by polymerizing propylene as a monomer, and mainly includes homopolymer polypropylene, copolymer polypropylene, and the like.

[0118] In the above technical solution, the support member 30 has good insulation performance, which can improve the stability of the battery device 100. In addition, the support member 30 has relatively stable chemical properties, which can increase the life of the battery device 100.

[0119] In some embodiments of the present invention, the support member 30 is a deformable elastic member. In other words, the support member 30 can be elastically deformed when subjected to an external force. As mentioned above, the support member 30 can be made of a polypropylene material, which provides the support member 30 with a certain degree of elasticity.

[0120] In the above technical solution, the support member 30 can be deformed. During the process of expansion and deformation of the soft-pack battery cell 10 , the stress of the soft-pack battery cell 10 can be reduced, thereby improving the use stability of the soft-pack battery cell 10 .

[0121] In one example, when the support member 30 is subjected to a pressure of 0.9 MPa, the support member 30 can be compressed by 80%. In other words, when the support member 30 is subjected to a pressure of 0.9 MPa, the thickness of the support member 30 is 20% of that before the pressure.

[0122] See also Figure 6 In some embodiments of the present invention, the battery device 100 includes a water-cooled plate 40, and the soft-pack battery cell 10 is thermally connected to the water-cooled plate 40. Specifically, the soft-pack battery cell 10 can be in direct contact with the water-cooled plate 40 or indirectly connected. The water-cooled plate 40 can be arranged on one side of the soft-pack battery cell 10 along the second direction Y. A flowing heat-conducting liquid can be passed into the interior of the water-cooled plate 40, and the heat-conducting liquid can exchange heat with the soft-pack battery cell 10 during the flow process, thereby adjusting the temperature of the soft-pack battery cell 10. In the above technical solution, the water-cooled plate 40 can cool the soft-pack battery cell 10 and reduce the temperature rise of the soft-pack battery cell 10.

[0123] See also Figure 6 In some embodiments of the present invention, the pouch cell 10 rests on the water cooling plate 40 along the second direction Y, where the first direction X intersects the second direction Y. For example, the second direction Y is perpendicular to the first direction X. When the battery device 100 is in normal use, the second direction Y can be vertical, and the water cooling plate 40 can be located at the bottom of the pouch cell 10.

[0124] In the above technical solution, the soft-pack battery cell 10 is supported on the water-cooling plate 40, so that the soft-pack battery cell 10 is close to the water-cooling plate 40. This can improve the heat exchange efficiency between the soft-pack battery cell 10 and the water-cooling plate 40, and thus can quickly reduce the temperature rise of the soft-pack battery cell 10.

[0125] See also Figure 6 In some embodiments of the present invention, a heat conducting member 50 is provided between the water cooling plate 40 and the soft-pack battery cell 10, and the heat conducting member 50 connects the soft-pack battery cell 10 and the water cooling plate 40. Specifically, the heat conducting member 50 can be a thermally conductive adhesive, such as a thermally conductive silicone gel, an epoxy thermally conductive adhesive, or the like.

[0126] In the above technical solution, the heat conducting member 50 can improve the heat exchange efficiency between the water-cooling plate 40 and the soft-pack battery cell 10 , which is beneficial for the water-cooling plate 40 to cool the soft-pack battery cell 10 .

[0127] According to some embodiments of the present invention, optionally, the soft-pack battery cell 10 is any one of a lithium iron phosphate battery cell, a ternary battery cell, and a solid-state battery cell.

[0128] The solid-state battery cell may 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 may also be a semi-solid-state battery cell or a fully solid-state battery cell.

[0129] In the above technical solution, the use of the above-mentioned types of soft-pack cells 10 can provide more options for battery device design to meet different usage requirements. Among them, the soft-pack cells 10 are lithium iron phosphate battery cells, which have the advantages of high reliability, long cycle life, light weight, large capacity, and low internal resistance; the soft-pack cells 10 are ternary battery cells, which have the advantages of high energy density and good electrochemical performance; and the soft-pack cells 10 are solid-state battery cells, which have the advantages of high energy density, high reliability, light weight, and good high and low temperature performance.

[0130] According to some embodiments of the present invention, optionally, the soft-pack battery cell 10 is a lithium iron phosphate battery cell, and in the positive electrode material of the soft-pack battery cell 10, 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 10 is a ternary battery cell, and in the positive electrode material of the soft-pack battery cell 10, the usage ratio of the positive electrode active material, the binder, and the conductive agent is 96: (2-3): (1-2).

[0131] In some embodiments, the positive electrode of the soft-pack battery cell 10 may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode film layer provided on at least one surface of the positive electrode current collector, wherein the positive electrode film layer includes a positive electrode active material.

[0132] 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 either or both of the two opposite surfaces of the positive electrode current collector.

[0133] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, the metal foil may include stainless steel, copper, aluminum, nickel, carbon electrodes, aluminum or stainless steel treated with carbon, nickel, titanium, or silver. A composite current collector may include a polymer base layer and a metal layer. The composite current collector can be formed by forming a metal material (such as aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy) onto a polymer substrate (such as polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0134] For example, when the pouch cell 10 of an embodiment of the present invention is a lithium-ion battery, the positive electrode active material may include at least one of the following materials: phosphates, layered transition metal oxides, and their respective modified compounds. Alternatively, the positive electrode active material may include layered transition metal oxides and their respective modified compounds, which may help improve the energy density of the pouch cell 10. However, the present invention is not limited to these materials; other conventional materials that can be used as battery positive electrode film layers may also be used. These positive electrode active materials may be used alone or in combination.

[0135] 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.

[0136] Layered transition metal oxides include those of the general formula Li a Ni b Co c M d O e A f At least one compound and its modified compound. 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.

[0137] Examples of layered transition metal oxides 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 (e.g., 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.

[0138] When the soft-pack battery cell 10 of the embodiment of the present invention 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.

[0139] As an example, the positive 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 (PO4) r O x Y 3-x At least one of the materials. p M' q (PO4) r O x Y 3-x wherein 0<p≤4, 0<q≤2, 1≤r≤3, 0≤x≤2, X comprises 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.

[0140] In the embodiment of the present invention, 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.

[0141] The charge and discharge process of the soft-pack battery cell 10 is accompanied by the deintercalation and consumption of active ions such as Li. The molar content of Li in the soft-pack battery cell 10 varies when discharged to different states. The molar content of Li in the examples of the present invention regarding the positive electrode active materials is the initial state of the material, i.e., the state before the materials are added. When the positive electrode active material is used in a battery system, the molar content of Li may change after charge and discharge cycles.

[0142] In the examples of the present invention regarding the positive electrode active materials, the molar content of oxygen O is only a theoretical value. Lattice oxygen release will cause the molar content of oxygen O to change. In practice, the molar content of oxygen O will fluctuate.

[0143] In the embodiments of the present invention, the element content in the positive electrode active material has a meaning well known in the art and can be measured using equipment and methods known in the art. For example, in accordance with EPA 6010D-2014, it can be measured by inductively coupled plasma atomic emission spectrometry (ICP-OES, Thermo ICAP7400). First, 0.4 g of the positive electrode active material was weighed and 10 ml of 50% aqua regia was added. The mixture was then placed on a plate at 180°C for 30 minutes. After digestion on the plate, the volume was adjusted to 100 mL and quantitative analysis was performed using a standard curve method.

[0144] In some embodiments, a positive electrode may be a metal foam. The metal foam may be nickel foam, copper foam, aluminum foam, alloy foam, or carbon foam, among others. When a metal foam is used as the positive electrode, a positive electrode film layer may or may not be provided on the surface of the metal foam. As an example, a lithium source material, potassium metal, or sodium metal may be filled and / or deposited within the metal foam, where the lithium source material is lithium metal and / or a lithium-rich material.

[0145] In some embodiments, the positive electrode film layer may further optionally include a positive electrode conductive agent. The present invention does not particularly limit the type of positive electrode conductive agent. By way of example, the positive 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 positive electrode conductive agent in the positive electrode film layer is ≤5 wt%.

[0146] In some embodiments, the positive electrode film layer may also optionally include a positive electrode binder. The present invention does not particularly limit the type of positive electrode binder. For example, the positive electrode binder may include at least one of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), a vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, a vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, a tetrafluoroethylene-hexafluoropropylene copolymer, and a fluorinated acrylic resin. In some embodiments, the mass percentage of the positive electrode binder in the positive electrode film layer is ≤5 wt%.

[0147] The positive electrode film layer is typically formed by coating a positive electrode slurry onto a positive electrode current collector, drying it, and cold pressing it. The positive electrode slurry is typically formed by dispersing the positive electrode active material, an optional conductive agent, an optional binder, and any other components in a solvent and stirring them uniformly. The solvent can be, but is not limited to, N-methylpyrrolidone (NMP).

[0148] In some embodiments, the negative electrode may be a negative electrode sheet, 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.

[0149] 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 either or both of the two opposite surfaces of the negative electrode current collector.

[0150] As examples, the negative electrode current collector can be a metal foil, metal foam, or composite current collector. For example, the metal foil can include silver-treated aluminum or stainless steel, copper, aluminum, nickel, carbon electrodes, carbon, nickel, or titanium. The metal foam can be nickel foam, copper foam, aluminum foam, alloy foam, or carbon foam. The composite current collector can include a polymer base layer and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, or silver alloy) onto a polymer substrate (such as polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0151] As an example, the negative electrode active material may adopt the negative electrode active material for the soft-pack battery cell 10 that is well known in the art. As an example, the negative electrode active material may include at least one of the following materials: a carbon material (for example, the carbon material includes at least one of artificial graphite, natural graphite, soft carbon, and hard carbon), a silicon-based material, a tin-based material, and lithium titanate, etc. The silicon-based material may include at least one of elemental silicon, a silicon oxide compound, a silicon-carbon composite, a silicon-nitrogen composite, and a silicon alloy. The tin-based material may include at least one of elemental tin, a tin oxide compound, and a tin alloy. However, the present invention 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.

[0152] In some embodiments, the negative electrode active material includes silicon. The silicon may be present in the form of a silicon-based material. For example, the silicon-based material may include at least one of elemental silicon, a silicon-oxygen compound, a silicon-carbon complex, a silicon-nitrogen complex, and a silicon alloy. The introduction of silicon can increase the energy density of the pouch cell 10.

[0153] In some embodiments, the mass content of silicon in the negative electrode film layer is 1 wt% to 32 wt%, optionally 2 wt% to 19 wt%, and further optionally 6 wt% to 13 wt%. In the soft-pack battery cell 10 system, when the mass content of silicon is within the above range, the energy density of the soft-pack battery cell 10 can be improved.

[0154] In the embodiments of the present invention, 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 placed in a solvent such as water for immersion, 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 from Thermo Fisher Scientific, USA, with reference to GB / T30902-2014 standard to obtain the silicon content.

[0155] In some embodiments, the negative electrode film layer may further optionally include a negative electrode conductive agent. The present invention does not particularly limit the type of negative electrode conductive agent. For 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 ≤ 5 wt%.

[0156] In some embodiments, the negative electrode film layer may also optionally include a negative electrode binder. The present invention does not specifically limit the type of negative electrode binder. For example, the negative electrode binder may include at least one of styrene-butadiene rubber (SBR), water-soluble unsaturated resin SR-1B, water-based acrylic resins (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 weight percentage of the negative electrode binder in the negative electrode film layer is ≤5%.

[0157] In some embodiments, the negative electrode film layer may optionally include other additives. For example, these additives may include thickeners, such as sodium carboxymethylcellulose (CMC-Na), PTC thermistor materials, and the like. In some embodiments, the mass percentage of these additives in the negative electrode film layer is ≤ 2 wt%.

[0158] 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.

[0159] In some embodiments, the separator includes a separator. The present invention 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.

[0160] The embodiment of the present invention has no particular limitation on the type of isolation membrane, and any known isolation membrane with a porous structure having good chemical stability and mechanical stability can be selected.

[0161] In some embodiments, the material of the separator may include one or more of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film, without particular limitation. When the separator is a multi-layer composite film, the materials of each layer may be the same or different, without particular limitation.

[0162] In some embodiments, the separator may include a porous base membrane and a coating layer disposed on at least one side of the porous base membrane, and the coating layer may include at least one of inorganic particles or organic particles.

[0163] The porous base membrane may include one or more of polyethylene and polypropylene.

[0164] The inorganic particles have good heat resistance and can improve the overall heat resistance of the separator. Within the operating voltage range of the sodium-ion battery, the inorganic particles essentially do not undergo oxidation and reduction reactions with metal dendrites. In other words, the inorganic particles are configured to not undergo oxidation and reduction reactions with alkali metals and / or alkaline earth metals at the nominal voltage of the sodium-ion battery.

[0165] In some embodiments, the inorganic particles include one or more of boehmite γ-AlOOH, aluminum oxide Al2O3, aluminum hydroxide Al(OH)3, barium sulfate BaSO4, magnesium oxide MgO, magnesium hydroxide Mg(OH)2, calcium oxide CaO, cerium oxide CeO2, zirconium titanate SrTiO3, barium titanate BaTiO3 and magnesium fluoride MgF2.

[0166] 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.

[0167] In some embodiments, the soft-pack battery cell 10 further includes an electrolyte.

[0168] During the charge and discharge process of a battery cell, active ions are embedded and released back and forth between the positive and negative electrodes, and the electrolyte conducts the active ions between the positive and negative electrodes. The present invention does not specifically limit the type of electrolyte, and the electrolyte can be selected based on actual needs.

[0169] The electrolyte solution includes an electrolyte salt and a solvent. The types of the electrolyte salt and the solvent are not particularly limited and can be selected according to actual needs.

[0170] In some embodiments, the electrolyte may optionally include additives. For example, the additives may include negative electrode film-forming additives, positive electrode film-forming additives, or 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.

[0171] 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.

[0172] It can be understood that when the soft-pack battery cell 10 is a lithium iron phosphate battery cell, in the positive electrode material of the soft-pack battery cell 10, the positive electrode active material accounts for 96 parts by weight of the total positive electrode material, the binder accounts for 1 to 3 parts by weight of the total 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 by weight of the total 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.).

[0173] For example, when the soft-pack battery cell 10 is a lithium iron phosphate battery cell, the positive electrode active material is LFP (which can be LiFePO4, i.e., lithium iron phosphate), the binder can be PVDF (polyvinylidene fluoride), and the conductive agent can be conductive carbon black. The ratio of LFP:PVDF:conductive carbon black can be 96:2:2. That is, out of 100 parts by weight of the total positive electrode active material, LFP accounts for 96 parts, PVDF accounts for 2 parts, and conductive carbon black also accounts for 2 parts. The weight of the positive electrode active material can be expressed in grams.

[0174] When the soft-pack cell 10 is a ternary battery cell, the positive electrode material of the soft-pack cell 10 comprises 96 parts by weight of the positive electrode active material, 2-3 parts by weight of the binder (e.g., including but not limited to 2, 2.2, 2.5, 2.8, 3, etc.), and 1-2 parts by weight of the conductive agent (e.g., including but not limited to 1, 1.2, 1.5, 1.8, 2, etc.). The ternary battery cell may be, but is not limited to, a lithium nickel cobalt manganese oxide (LNO)-based battery, a lithium nickel cobalt aluminum oxide (LNO)-based battery, or the like.

[0175] 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, the 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.

[0176] In the above technical solution, when the soft-pack battery cell 10 is a lithium iron phosphate battery cell, a high proportion of positive electrode active material means that more substances capable of undergoing electrochemical reactions can be accommodated within a limited electrode assembly, which is beneficial to increasing the capacity and energy density of the battery device 100. This allows the lithium iron phosphate battery cell to output a higher amount of electricity while being relatively small in volume and weight, meeting application scenarios with certain requirements for energy density. The use of the binder and conductive agent within 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 10 is a ternary battery cell, due to the relatively complex structure and surface properties of the ternary material itself, the use of the positive electrode active material, binder, and conductive agent in the above ratio 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, reducing the risk of active material shedding and electrode pulverization during charging and discharging, and extending the cycle life of the battery device 100.

[0177] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and description of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in each embodiment can be combined in any way. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery device, characterized in that: The battery device comprises: A plurality of soft-pack battery cells, wherein the plurality of soft-pack battery cells are arranged along a first direction; a heat sink, the heat sink being arranged between two adjacent soft-pack battery cells; and A support member, wherein the support member is arranged at the edge of the heat sink, the support member abuts the soft-pack battery cell, the support member surrounds the heat sink, the soft-pack battery cell includes a first outer surface, the first outer surface is the largest surface of the soft-pack battery cell, the first outer surfaces of multiple soft-pack battery cells are arranged along the first direction, the heat sink is arranged between the first outer surfaces of two adjacent soft-pack battery cells, and the outer contour area of ​​the support member is smaller than the area of ​​the first outer surface of the soft-pack battery cell.

2. The battery device according to claim 1, wherein: The projection of the heat dissipation element in the first direction is located within the first outer surface of the soft-pack battery core.

3. The battery device according to claim 1 or 2, characterized in that The surface of the heat sink facing the soft-pack battery core is a plane.

4. The battery device according to any one of claims 1 to 2, characterized in that: The heat sink is spaced apart from the soft-pack battery cell.

5. The battery device according to any one of claims 1 to 2, characterized in that: The heat sink is a solid structural component.

6. The battery device according to any one of claims 1-2, characterized in that: The heat sink is a plate-shaped member with a constant thickness, and the thickness direction of the heat sink is the same as the first direction.

7. The battery device according to any one of claims 1 to 2, characterized in that: The heat sink is a metal part.

8. The battery device according to any one of claims 1 to 2, characterized in that: The thickness of the heat sink is D1, 0.2 mm ≤ D1 ≤ 2 mm.

9. The battery device according to claim 1, wherein: The support member is combined with a side surface of the heat dissipation member.

10. The battery device according to claim 1, wherein: Along the first direction, the thickness of the support member is greater than the thickness of the heat dissipation member.

11. The battery device according to claim 1, wherein: Along the first direction, a thickness ratio of the support member to the soft-pack battery cell is less than 10%.

12. The battery device according to claim 1, wherein: The support member is made of polypropylene material.

13. The battery device according to claim 1, wherein: The supporting member is a deformable elastic member.

14. The battery device according to any one of claims 1 to 2, characterized in that: The battery device includes a water cooling plate, and the soft-pack battery cell is thermally connected to the water cooling plate.

15. The battery device according to claim 14, characterized in that The soft-pack battery cell rests on the water-cooling plate along a second direction, and the first direction intersects with the second direction.

16. The battery device according to claim 15, characterized in that A heat conducting member is provided between the water cooling plate and the soft-pack battery core, and the heat conducting member connects the soft-pack battery core and the water cooling plate.

17. The battery device according to any one of claims 1-2, 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.

18. An electrical device, characterized in that: The electrical equipment comprises the battery device according to any one of claims 1 to 17.

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