Battery apparatus and electric device

Abstract

A battery apparatus (100) and an electric device (200). The battery apparatus (100) comprises a plurality of battery packs (10); the battery packs (10) are sequentially arranged in a first direction; each battery pack (10) comprises a housing (11) and at least one pouch cell (12); the pouch cell (12) is arranged in the housing (11); and a thermal insulating member (20) is arranged between at least two adjacent battery packs (10) among the plurality of battery packs (10).

Description

Battery device and electric appliance TECHNICAL FIELD

[0001] The present application relates to the technical field of battery, in particular to a battery device and an electric appliance. BACKGROUND

[0002] In the related art, there is a problem of high difficulty in thermal protection between adjacent battery groups of a soft package battery device, which affects the further improvement of the reliability of the soft package battery device. SUMMARY

[0003] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, one object of the present application is to provide a battery device and an electric appliance, which has higher reliability.

[0004] The present application provides a battery device, comprising: a plurality of battery groups, the battery groups being arranged in sequence along a first direction, each battery group comprising a cladding shell and at least one soft package battery cell, the soft package battery cell being arranged in the cladding shell; wherein at least two adjacent battery groups among the plurality of battery groups are provided with a heat insulation member.

[0005] According to the battery device of the embodiments of the present application, by arranging the heat insulation member between at least two adjacent battery groups, the heat transfer between the plurality of battery groups can be improved, and the high-pressure gas fire flow can be buffered by the heat insulation member, so as to reduce the heat runaway spread speed between the battery groups, thereby improving the reliability of the battery device.

[0006] According to some embodiments of the present application, a heat insulation member is arranged between any two adjacent battery groups.

[0007] According to some embodiments of the present application, the heat insulation member is configured as any one of a nano heat insulation material member, a glass fiber heat insulation material member, and a ceramic fiber heat insulation material member.

[0008] According to some embodiments of the present application, the thickness dimension of the heat insulation member in the first direction is 1mm-4mm.

[0009] According to some embodiments of the present application, the soft package battery cell is configured as a lithium iron phosphate battery; and when the total electric quantity inside the two adjacent battery groups is less than 0.5KWh, no heat insulation member is arranged between the two adjacent battery groups.

[0010] According to some embodiments of the present application, the soft package battery cell is configured as a Lithium iron phosphate battery; and when the total electric quantity inside the battery group is less than or equal to 1KWh and greater than or equal to 0.5KWh, a heat insulation member is arranged between the battery group and the adjacent battery group, and the thickness of the heat insulation member is 1mm-2mm.

[0011] According to some embodiments of the present application, the soft package battery cell is configured as a lithium iron phosphate battery; and when the total electric quantity inside the battery pack is greater than 1 KWh, a heat insulation piece is arranged between the battery pack and the adjacent battery pack, and the thickness of the heat insulation piece is 2-3 mm.

[0012] According to some embodiments of the present application, the soft package battery cell is configured as a ternary lithium battery; and when the total electric quantity inside the adjacent two battery packs is less than 0.5 KWh, no heat insulation piece is arranged between the two battery packs.

[0013] According to some embodiments of the present application, the soft package battery cell is configured as a ternary lithium battery; and when the total electric quantity inside the battery pack is less than or equal to 1 KWh and greater than or equal to 0.5 KWh, a heat insulation piece is arranged between the battery pack and the adjacent battery pack, and the thickness of the heat insulation piece is 2-3 mm.

[0014] According to some embodiments of the present application, the soft package battery cell is configured as a ternary lithium battery; and when the total electric quantity inside the battery pack is greater than 1 KWh, a heat insulation piece is arranged between the battery pack and the adjacent battery pack, and the thickness of the heat insulation piece is 3-4 mm.

[0015] According to some embodiments of the present application, the cladding shell comprises: a first plate and a second plate located on both sides of the first plate in the first direction, the second plate is opposite to the soft package battery cell in the first direction, and the heat insulation piece is connected with the second plate.

[0016] According to some embodiments of the present application, an end of the second plate away from the first plate forms an opening, and the cladding shell is connected with the box body of the battery device through the opening position.

[0017] According to some embodiments of the present application, the box body has a bottom plate, and the end surface of the second plate away from the first plate is connected with the bottom plate through a glue layer.

[0018] According to some embodiments of the present application, the bottom plate comprises a cold plate, and the glue layer is located between the cold plate and the plurality of soft package battery cells.

[0019] According to some embodiments of the present application, the glue layer comprises: a glue layer body and a glue overflow part, the glue overflow part is located on the side of the glue layer body facing the plurality of soft package battery cells, and is located between the adjacent soft package battery cells, and / or between the soft package battery cell and the second plate, and / or between the second plate and the heat insulation piece.

[0020] According to some embodiments of the present application, the soft package battery cell comprises: a flexible shell and an electrode assembly arranged in the flexible shell, the flexible shell has a side surface opposite to a large surface of the electrode assembly and a circumferential surface avoiding the large surface, the side surface and / or the circumferential surface is provided with a weak part, the cladding shell has a pressure relief part at least partially opposite to the weak part, and the pressure relief part is formed in the first plate.

[0021] According to some embodiments of the present application, the soft-packing battery monomer is projected along the first direction, and the projection profile of the soft-packing battery monomer is within the projection profile of the heat insulation piece.

[0022] According to some embodiments of the present application, the heat insulation piece is configured as one or more of a mica plate, a foam plate, and an aerogel plate.

[0023] According to some embodiments of the present application, the soft-packing battery monomer is any one of a lithium iron phosphate battery monomer, a ternary lithium battery monomer, and a solid-state battery monomer.

[0024] According to some embodiments of the present application, the battery monomer is a lithium iron phosphate battery monomer, and the amount ratio of the positive electrode active material, the positive electrode binder, and the positive electrode conductive agent in the positive electrode material of the battery monomer is 96:(1-3):(1-3); the battery monomer is a ternary lithium battery monomer, and the amount ratio of the positive electrode active material, the positive electrode binder, and the positive electrode conductive agent in the positive electrode material of the battery monomer is 96:(2-3):(1-2).

[0025] The present application provides a power-consuming device, comprising the battery device in the above embodiments.

[0026] According to some embodiments of the present application, the power-consuming device is a vehicle.

[0027] According to some embodiments of the present application, the battery device is integrated into the chassis of the vehicle, and the top plate of the box body participates in defining the floor of the vehicle body.

[0028] Additional aspects and advantages of the present application will be in part apparent and in part pointed out hereinafter. BRIEF DESCRIPTION OF DRAWINGS

[0029] The above and / or additional aspects and advantages of the present application will become apparent and be readily appreciated from the following description, taken in conjunction with the following drawings in which:

[0030] FIG. 1 is a schematic diagram of a power-consuming device according to an embodiment of the present application;

[0031] FIG. 2 is a schematic diagram of a battery device according to an embodiment of the present application;

[0032] FIG. 3 is a schematic diagram of a battery pack and a heat insulation piece according to an embodiment of the present application (a heat insulation piece is arranged between adjacent battery packs);

[0033] FIG. 4 is a schematic diagram of a battery pack according to an embodiment of the present application;

[0034] FIG. 5 is a schematic diagram of the cooperation between a battery pack and a floor according to an embodiment of the present application;

[0035] FIG. 6 is a schematic diagram of a soft-packing battery monomer according to an embodiment of the present application;

[0036] FIG. 7 is a schematic view of a battery pack and a thermal insulation member (one thermal insulation member) according to an embodiment of the present application;

[0037] FIG. 8 is a schematic view of a battery pack and a thermal insulation member (one thermal insulation member is arranged between two battery packs) according to an embodiment of the present application. DETAILED DESCRIPTION

[0038] Embodiments of the present application are described in detail below with reference to the accompanying drawings. The embodiments described below are examples for explaining the present application and should not be understood as limiting the present application.

[0039] In the description of the present application, it should be understood that the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0040] It should be noted that the terms "first", "second" are only for the purpose of description and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features referred to. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. Further, in the description of the present application, unless otherwise stated, the meaning of "a plurality of" is two or more.

[0041] The soft-pack battery cell can be a secondary battery, which refers to a soft-pack battery cell that can be activated by charging after discharging.

[0042] The soft-pack battery cell can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel-hydrogen battery, a nickel-cadmium battery, a lead-acid battery, etc., and the embodiments of the present application are not limited thereto.

[0043] The battery device mentioned in the embodiments of the present application can include one or more battery packs for providing voltage and capacity. The battery pack can include a plurality of soft-pack battery cells connected in series, in parallel, or in a mixed connection through a busbar.

[0044] In some embodiments, the battery pack is generally formed by arranging a plurality of soft-pack battery cells.

[0045] In some embodiments, the battery device can be a battery pack, the battery pack comprising a box and one or more battery groups, the battery groups being accommodated in the box.

[0046] As an example, the battery group can be a battery module, the battery group being accommodated in the box by fixing the battery module in the box.

[0047] As an example, the box can comprise a first box and a second box. The first box and the second box are buckled so that a closed space is formed inside the box to accommodate the battery group. Here, closed means covered or closed, which can be sealed or unsealed. The first box can be a top cover or a bottom plate.

[0048] As an example, the box can comprise a top cover, a frame and a bottom plate. The top cover and the bottom plate are connected with the frame respectively, so that a closed space is formed inside the box to accommodate the battery group.

[0049] In some embodiments, the box can be part of the chassis structure of the vehicle. For example, part of the box can be at least part of the floor of the vehicle, or part of the box can be at least part of the cross beam and the longitudinal beam of the vehicle.

[0050] The technical solutions described in the embodiments of the present application are applicable to battery devices and electric equipment using battery devices.

[0051] The electric equipment can be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy and an electric tool, etc. The vehicle can be a fuel automobile, a gas automobile or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid electric automobile or a range extended automobile, etc. The spacecraft includes an airplane, a rocket, a space shuttle and a spacecraft, etc. The electric toy includes a fixed or mobile electric toy, for example, a game console, an electric automobile toy, an electric ship toy and an electric airplane toy, etc. The electric tool includes a metal cutting electric tool, a grinding electric tool, an assembling electric tool and a railway electric tool, for example, an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact electric drill, a concrete vibrator and an electric planer, etc. The embodiments of the present application do not specially limit the above electric equipment.

[0052] The following embodiments take the vehicle as an example for convenience of description.

[0053] Please refer to FIG. 1, which is a structural schematic diagram of a vehicle provided by some embodiments of the present application. The vehicle is internally provided with a battery device 100, which can be arranged at the bottom, the head or the tail of the vehicle. The battery device 100 can be used for power supply of the vehicle, for example, the battery device 100 can be used as the operating power supply of the vehicle.

[0054] The vehicle can further include a controller 400 and a motor 300, the controller 400 being configured to control the battery device 100 to supply power to the motor 300, the motor 300 being configured as a load, for example, for power requirements of the vehicle during starting, navigation, and driving.

[0055] In some embodiments of the present application, the battery device 100 can not only serve as a power source for operating the vehicle, but also serve as a driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0056] Referring to FIG. 2, an exploded view of the battery device 100 is shown. The battery device 100 includes a box 30 configured to accommodate the pouch battery cells 12.

[0057] The box 30 is a component configured to accommodate the pouch battery cells 12, and the box 30 provides a space for the battery pack 10. The box 30 can have various structures. In some embodiments, the box 30 can include a tray and a cover plate, and the tray and the cover plate are coupled to each other to define a space for accommodating the pouch battery cells 12. The tray and the cover plate can have various shapes, such as a cuboid, a cylinder, and the like. The tray can be a hollow structure with one side open, and the cover plate can also be a hollow structure with one side open. The open side of the cover plate is coupled to the open side of the tray to form the box 30 with the space. Alternatively, the tray can be a hollow structure with one side open, and the cover plate can be a plate structure. The cover plate is coupled to the open side of the tray to form the box 30 with the space.

[0058] In the battery device 100, the pouch battery cells 12 can be one or multiple. The multiple pouch battery cells 12 are loaded into one battery pack 10 by the cladding shell 11, and one or more battery packs 10 are loaded into the box 30. If the pouch battery cells 12 are multiple, the multiple pouch battery cells 12 can be connected in series, in parallel, or in a mixed connection. The mixed connection means that the multiple pouch battery cells 12 are connected in series and in parallel. The multiple pouch battery cells 12 can be connected in series, in parallel, or in a mixed connection to form the battery pack 10, and the multiple battery packs 10 can be connected in series, in parallel, or in a mixed connection to form an integral whole and be accommodated in the box 30.

[0059] Referring to FIG. 6, the pouch battery cell 12 is the smallest energy unit of the battery device 100. The pouch battery cell 12 includes a flexible shell 121 and an electrode assembly 122 disposed in the flexible shell 121.

[0060] The flexible shell 121 forms an internal environment for accommodating the electrode assembly 122, an electrolyte, and other components. One side of the flexible shell 121 can be formed with an opening for injecting the electrolyte and the electrode assembly 122 into the shell.

[0061] As shown in FIG. 6, the tab of the electrode assembly 122 penetrates the flexible outer shell 121, and the tab is electrically connected to the busbar. The electrode assembly 122 is a component in which electrochemical reactions occur in the soft-pack battery cell 12. One or more electrode assemblies 122 can be contained in the flexible outer shell 121. The electrode assembly 122 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is usually provided between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet and the negative electrode sheet each have a portion with an active material that constitutes a main body of the electrode assembly 122, and each has a portion without the active material that constitutes a tab. The positive electrode tab and the negative electrode tab can be located together at one end of the main body or can be located at opposite ends of the main body. During charging and discharging of the battery device 100, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tabs are connected to the busbar to form a current loop.

[0062] The positive electrode tab can include a positive electrode current collector and a positive electrode film layer provided on at least one surface of the positive electrode current collector. The positive electrode film layer includes a positive electrode active material.

[0063] As an example, the positive electrode current collector has two opposite surfaces in the thickness direction thereof, and the positive electrode film layer is provided on either one or both of the two opposite surfaces of the positive electrode current collector.

[0064] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as the metal foil, stainless steel, copper, aluminum, nickel, a carbon electrode, carbon, nickel, titanium, silver surface-treated aluminum, or stainless steel, etc. can be used. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0065] As an example, when the soft-pack battery cell 22 of the embodiment of the present application is a lithium ion battery, the positive electrode active material can include at least one of the following materials: phosphate, layered transition metal oxide, and a modified compound of each of them; optionally, the positive electrode active material can include layered transition metal oxide and a modified compound of each of them, which is advantageous to improve the energy density of the soft-pack battery cell 22. However, the present application is not limited to these materials, and other conventional materials that can be used as a positive electrode film layer of a battery can also be used. These positive electrode active materials can be used alone or in combination with two or more.

[0066] Examples of the phosphate can 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 manganese iron phosphate, and a composite material of lithium manganese iron phosphate and carbon.

[0067] Layered transition metal oxides include at least one of compounds of the general formula Li a Ni b Co c M d O e A f 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, and further optionally, 0.75≤b≤0.98.

[0068] Examples of layered transition metal oxides can 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 can be referred to simply as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O2(also can be referred to simply as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O2(also can be referred to simply as NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O2(also can be referred to simply as NCM 622 ), LiNi 0.8 Co 0.1 Mn 0.1 O2(also can be referred to simply as NCM 811 ), LiNi 0.9 Co 0.05 Mn 0.05 O2(also can be referred to simply as Ni90), lithium nickel cobalt aluminum oxide (e.g., LiNi 0.80 Co 0.15 Al 0.05 O2), and modified compounds thereof, etc.

[0069] When the soft package battery cell 22 in the embodiments of the present application is a sodium ion battery, the positive electrode active material can include, but is not limited to, at least one of a sodium-containing transition metal oxide, a polyanion material (such as a phosphate, a fluorophosphate, a pyrophosphate, a sulfate, etc.), a Prussian blue type material.

[0070] As an example, the positive electrode active material for a sodium ion battery can include at least one of 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, a Prussian blue type material, a material of a general formula X p M’ q (PO4) r O x Y 3-x . In the general formula X p M’ q (PO4) r 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, which can be at least one of V, Ti, Mn, Fe, Co, Ni, Cu and Zn, and Y is a halide anion, which can be at least one of F, Cl and Br.

[0071] 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, such as carbon coating modification, fast ion conductor coating modification, etc.

[0072] The soft package battery cell 22 will be accompanied by the deintercalation and consumption of active ions such as Li during the charging and discharging process, and the molar content of Li is different when the soft package battery cell 22 is discharged to different states. In the embodiments of the present application, the enumeration of the positive electrode active material is the molar content of Li in the initial state of the material, i.e. the state before feeding, and the positive electrode active material is applied to the battery system. After charging and discharging cycles, the molar content of Li can change.

[0073] In the enumeration of the positive electrode active material in the embodiments of the present application, the molar content of oxygen O is only the theoretical state value, and the release of oxygen from the lattice will cause the molar content of oxygen O to change. In practice, the molar content of oxygen O will appear to be floating.

[0074] In the embodiments of the present application, the content of elements in the positive electrode active material is the meaning known in the art, which can be detected by using the devices and methods known in the art, for example, referring to EPA 6010D-2014, tested by inductively coupled plasma atomic emission spectrometry, and determined by plasma atomic emission (ICP-OES, instrument model: Thermo ICAP7400). First, 0.4g of the positive electrode active material is weighed, and 10ml (50% concentration) aqua regia is added thereto. Then it is placed on a 180℃ flat plate for 30min. After digestion on the flat plate, it is diluted to a volume of 100mL, and the quantitative test is performed by the standard curve method.

[0075] In some embodiments, the positive electrode can use a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. When the foamed metal is used as the positive electrode, the surface of the foamed metal can not be provided with a positive electrode film layer, of course, it can also be provided with a positive electrode film layer. As an example, the foamed metal can also be filled or / and deposited with a lithium source material, potassium metal or sodium metal, and the lithium source material is lithium metal and / or lithium-rich material.

[0076] In some embodiments, the positive electrode film layer can also optionally include a positive electrode conductive agent. The type of positive electrode conductive agent is not particularly limited in the embodiments of the present application, 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 content of the positive electrode conductive agent in the positive electrode film layer is ≤5wt%.

[0077] In some embodiments, the positive electrode film layer can also optionally include a positive electrode binder. The type of positive electrode binder is not particularly limited in the embodiments of the present application, as an example, the positive electrode binder can 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 ester resin. In some embodiments, the mass percentage content of the positive electrode binder in the positive electrode film layer is ≤5wt%.

[0078] 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, the optional conductive agent, the optional binder and any other components in a solvent and stirring uniformly. The solvent can be N-methyl pyrrolidone (NMP), but is not limited thereto.

[0079] In some embodiments, the negative electrode can be a negative electrode tab, which can include a negative electrode current collector and a negative electrode film layer disposed on at least one surface of the negative electrode current collector, the negative electrode film layer including a negative electrode active material.

[0080] As an example, the negative electrode current collector has two surfaces opposite in the thickness direction of the negative electrode current collector, and the negative electrode film layer is disposed on either one or both of the two surfaces of the negative electrode current collector.

[0081] As an example, the negative electrode current collector can be a metal foil, a foamed metal, or a composite current collector. For example, as the metal foil, silver surface-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, a carbon electrode, or the like can be used. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. The composite current collector can include a polymer material 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, and silver alloy, etc.) on a polymer material base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0082] As an example, the negative electrode active material can employ a negative electrode active material known in the art for use in the soft-pack battery cell 22. As an example, the negative electrode active material can include at least one of a carbon material (e.g., the carbon material includes at least one of artificial graphite, natural graphite, soft carbon, hard carbon), a silicon-based material, a tin-based material, and lithium titanate, etc. The silicon-based material can 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 can include at least one of elemental tin, a tin oxide compound, and a tin alloy. However, the present application is not limited to these materials, and other conventional materials that can be used as a negative electrode film layer for a battery can also be used. These negative electrode film layers can be used alone or in combination with two or more.

[0083] In some embodiments, the negative electrode active material includes a silicon element, which can be present in the form of a silicon-based material, such as at least one of elemental silicon, a silicon oxide compound, a silicon-carbon composite, a silicon-nitrogen composite, and a silicon alloy. The introduction of the silicon element can improve the energy density of the soft-pack battery cell 22.

[0084] In some embodiments, the mass content of the silicon element 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%. When the mass content of the silicon element is within the above range in the system of the soft-pack battery cell 22, the energy density of the soft-pack battery cell 22 can be improved.

[0085] In the embodiments of the present application, the mass content of silicon in the negative electrode film layer is in the meaning known in the art, which can be detected by using the devices and methods known in the art, for example, the negative electrode sheet is placed in a solvent such as water for soaking, the negative electrode active material is separated from the negative electrode current collector, the negative electrode active material is obtained by suction filtration, and the content of silicon is obtained by using the inductively coupled plasma-optical emission spectrometer of ICAP7400 model of Thermo Fisher Scientific Company, USA, and referring to the standard GB / T30902-2014.

[0086] In some embodiments, the negative electrode film layer optionally further comprises a negative electrode conductive agent. The embodiments of the present application do not have special restrictions on the type of negative electrode conductive agent. As an example, the negative electrode conductive agent can comprise at least one of super-conductive carbon, conductive graphite, acetylene black, carbon black, ketjen black, carbon dots, carbon nanotubes, graphene and carbon nanofibers. In some embodiments, the mass percentage content of the negative electrode conductive agent in the negative electrode film layer is ≤5wt%.

[0087] In some embodiments, the negative electrode film layer optionally further comprises a negative electrode binder. The embodiments of the present application do not have special restrictions on the type of negative electrode binder. As an example, the negative electrode binder can comprise at least one of styrene butadiene rubber (SBR), water-soluble unsaturated resin SR-1B, water-based acrylic resin (for example, polyacrylic acid PAA, polymethylacrylic acid PMAA, sodium polyacrylate PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA) and carboxymethyl chitosan (CMCS). In some embodiments, the mass percentage content of the negative electrode binder in the negative electrode film layer is ≤5wt%.

[0088] In some embodiments, the negative electrode film layer optionally further comprises other auxiliary agents. As an example, the other auxiliary agents can comprise thickening agents, for example, carboxymethyl cellulose sodium (CMC-Na), PTC thermistor material, etc. In some embodiments, the mass percentage content of the other auxiliary agents in the negative electrode film layer is ≤2wt%.

[0089] In some embodiments, the material of the positive electrode current collector can be aluminum, and the material of the negative electrode current collector can be copper.

[0090] In some embodiments, the separator comprises a separator film. The embodiments of the present application do not have special restrictions on the type of separator film, and any known porous structure separator film with good chemical stability and mechanical stability can be selected.

[0091] The embodiments of the present application do not have special restrictions on the type of separator film, and any known porous structure separator film with good chemical stability and mechanical stability can be selected.

[0092] In some embodiments, the material of the separator may include one or more of glass fiber, nonwoven 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.

[0093] In some embodiments, the separator may include a porous base membrane and a coating disposed on at least one side of the porous base membrane, the coating including at least one of inorganic particles or organic particles.

[0094] Porous base membranes may include one or more of polyethylene and polypropylene.

[0095] Inorganic particles possess good heat resistance, which can improve the overall heat resistance of the separator. Within the operating voltage range of sodium-ion batteries, inorganic particles essentially do not undergo oxidation and reduction reactions with metal dendrites. In other words, inorganic particles are configured to prevent oxidation and reduction reactions with alkali metals and / or alkaline earth metals at the nominal voltage of sodium-ion batteries.

[0096] 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.

[0097] 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, polyarylamide, polyamide-imide, polyimide, copolymers of butyl acrylate and ethyl methacrylate, and mixtures thereof.

[0098] In some embodiments, the pouch cell 22 further includes an electrolyte.

[0099] During the charging and discharging process of a single battery cell, active ions repeatedly insert and extract between the positive and negative electrode plates, while the electrolyte acts as a conductor for these active ions. This application does not impose any particular restrictions on the type of electrolyte; it can be selected according to actual needs.

[0100] Electrolytes consist of electrolyte salts and solvents. The types of electrolyte salts and solvents are not specifically limited and can be selected according to actual needs.

[0101] 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, and additives that can improve certain battery performance, such as additives that improve battery overcharge performance, additives that improve battery high-temperature performance, and additives that improve battery low-temperature power performance.

[0102] For example, the additives include at least one of the following: cyclic carbonate compounds containing unsaturated bonds, sulfate compounds, sulfite compounds, sulfonyl lactone compounds, disulfonic acid compounds, nitrile compounds, aromatic compounds, isocyanate compounds, phosphonitrile compounds, acid anhydrides, cyclic acid anhydride compounds, phosphite compounds, phosphate compounds, borate esters, and carboxylic acid esters.

[0103] In related technologies, the casing 11 is disposed outside multiple pouch battery cells 12 and is used to support the pouch battery cells 12. Multiple battery packs 10 are arranged sequentially in the length direction and / or width direction of the battery device 100. The small spacing between adjacent battery packs 10 results in a faster heat diffusion rate between adjacent battery packs 10, which poses a safety hazard.

[0104] Based on this, this application proposes a battery device 100, which provides a heat insulation component 20 between adjacent battery packs 10 to achieve isolation and protection between adjacent battery packs 10, thereby reducing the thermal runaway propagation rate between adjacent battery packs 10 and improving the reliability of the battery device 100.

[0105] The battery device 100 and the electrical appliance 200 according to embodiments of this application are described below with reference to Figures 1-8.

[0106] As shown in Figures 2 and 3, this application proposes a battery device 100, including: a plurality of battery packs 10, the battery packs 10 being arranged sequentially along a first direction, the battery pack 10 including a casing 11 and at least one soft-pack battery cell 12, the soft-pack battery cell 12 being disposed within the casing 11, and in the plurality of battery packs 10, at least two adjacent battery packs 10 are provided with a heat insulation member 20.

[0107] Multiple battery packs 10 can be sequentially arranged in the housing 30 along a first direction, which can be the length direction of the battery device 100 or the width direction of the battery device 100. At least two adjacent battery packs 10 are provided with heat insulation components 20 so that heat transfer between the two adjacent battery cells can be blocked by the heat insulation components 20. At the same time, the heat insulation components 20 can also buffer the high-pressure gas flow (the high-pressure gas flow generated by the thermal runaway soft-pack battery cell 12 and carrying solid particles or liquid substances, which is defined as high-pressure gas flow) to reduce the thermal runaway propagation speed between adjacent battery packs 10.

[0108] The provision of a heat insulation element 20 between at least two adjacent battery packs 10 means that if there are three battery packs 10 in the first direction, which are respectively defined as the first group, the second group and the third group, then at least one of the first group and the second group, or the second group and the third group, is provided with a heat insulation element 20, or both are provided with a heat insulation element 20.

[0109] As shown in Figure 7, in some embodiments, a heat insulation element 20 may be provided inside the battery device 100. The heat insulation element 20 may be provided between any two adjacent battery packs 10 in the arrangement direction of the multiple battery packs 10 arranged sequentially, as shown in Figures 3 and 8. In other embodiments, multiple heat insulation elements 20 may be provided inside the battery device 100, and one battery pack 10 (see Figure 3) or two battery packs 10 (see Figure 8) may be provided between adjacent heat insulation elements 20. Of course, more than one battery pack 10 may also be provided, which will not be described in detail in this application.

[0110] According to the embodiments of this application, the battery device 100 can improve the heat transfer between multiple battery packs 10 by providing a heat insulation member 20 between at least two adjacent battery packs 10, and can buffer the high-pressure gas flow through the heat insulation member 20, thereby reducing the thermal runaway propagation rate between battery packs 10 and improving the reliability of the battery device 100.

[0111] In a further embodiment of this application, as shown in FIG3, a heat insulation component 20 is provided between any two adjacent battery packs 10. Compared with the provision of a heat insulation component 20 between at least two adjacent battery packs 10, the number of heat insulation components 20 is greater, and heat insulation can be achieved between each pair of adjacent battery packs 10. The heat insulation and buffer protection effects are better, which can further improve the reliability of the battery device 100.

[0112] According to some embodiments of this application, the thermal insulation element 20 is constructed as any one of a nano-insulating material, a glass fiber insulating material, and a ceramic fiber insulating material.

[0113] In other words, in some embodiments, the heat insulation component 20 is constructed as a nano-insulation material (a heat insulation material containing nano-sized pores), such as nano-alumina, nano-silica, nano-titanium oxide, etc., which can be obtained through processes such as sol-gel, vapor deposition, and combustion; in other embodiments, the heat insulation component 20 is constructed as a glass fiber heat insulation material, which is made from ores such as pyrophyllite, quartz sand, limestone, dolomite, borocalcite, and boromagnesia through processes such as high-temperature melting, drawing, winding, and weaving; in still other embodiments, the heat insulation component is constructed as a ceramic fiber heat insulation material, which is made by melting high-purity clay clinker, alumina powder, silica powder, and other raw materials at high temperature in an industrial electric furnace.

[0114] Therefore, by constructing the heat insulation component 20 as any of the aforementioned heat insulation materials, a stable and reliable thermal insulation effect can be obtained by using a heat insulation component 20 with a lower thickness, while taking into account the energy density of the battery device 100, under the premise that the heat insulation component 20 has a stable and reliable thermal insulation effect.

[0115] According to some embodiments of this application, the soft-pack battery cell 12 is configured as a lithium iron phosphate battery;

[0116] Furthermore, when the total internal capacity of two adjacent battery packs 10 is less than 0.5 kWh, there is no heat insulation component 20 between the two adjacent battery packs 10.

[0117] Furthermore, when the total capacity inside the battery pack 10 is less than or equal to 1 kWh and greater than or equal to 0.5 kWh, a heat insulation component 20 is provided between the battery pack 10 and the adjacent battery pack 10, and the thickness of the heat insulation component 20 is 1 mm to 2 mm.

[0118] Furthermore, when the total charge inside the battery pack 10 is greater than 1 kWh, a heat insulation component 20 is provided between the battery pack 10 and the adjacent battery pack 10, and the thickness of the heat insulation component 20 is 2 mm-3 mm.

[0119] Specifically, in embodiments where the pouch battery cell 12 is constructed as a lithium iron phosphate battery and the total internal capacity of the battery pack 10 is less than 0.5 kWh, no heat insulation component 20 is required between adjacent battery packs 10. This reduces the number of heat insulation components 20 while ensuring the reliability of the battery device 100, thereby lowering material costs and increasing energy density. In embodiments where the pouch battery cell 12 is constructed as a lithium iron phosphate battery and the total internal capacity of the battery pack 10 is less than or equal to 1 kWh and greater than or equal to 0.5 kWh, a heat insulation component 20 with a thickness of 1 mm to 2 mm is required between adjacent battery packs 10. This balances the reliability and energy density of the battery device 100. Similarly, in embodiments where the pouch battery cell 12 is constructed as a lithium iron phosphate battery and the total internal capacity of the battery pack 10 is greater than 1 kWh, a heat insulation component 20 with a thickness of 2 mm to 3 mm is required between adjacent battery packs 10. This makes the thickness of the heat insulation component 20 more reasonable, thus balancing the energy density of the battery device 100.

[0120] According to other embodiments of this application, the pouch cell 12 is configured as a ternary lithium battery;

[0121] Furthermore, when the total internal capacity of two adjacent battery packs 10 is less than 0.5 kWh, there is no heat insulation component 20 between the two adjacent battery packs 10.

[0122] Furthermore, when the total capacity inside the battery pack 10 is less than or equal to 1 kWh and greater than or equal to 0.5 kWh, a heat insulation component 20 is provided between the battery pack 10 and the adjacent battery pack 10, and the thickness of the heat insulation component 20 is 2 mm-3 mm.

[0123] When the total charge inside the battery pack 10 is greater than 1 kWh, a heat insulation component 20 is provided between the battery pack 10 and the adjacent battery pack 10, and the thickness of the heat insulation component 20 is 3 mm-4 mm.

[0124] Specifically, in embodiments where the pouch battery cell 12 is constructed as a ternary lithium battery and the total internal capacity of the battery pack 10 is less than 0.5 kWh, no heat insulation component 20 is required between adjacent battery packs 10. This reduces the number of heat insulation components 20 while ensuring the reliability of the battery device 100, thereby lowering material costs and increasing energy density. In embodiments where the pouch battery cell 12 is constructed as a ternary lithium battery and the total internal capacity of the battery pack 10 is less than or equal to 1 kWh and greater than or equal to 0.5 kWh, a heat insulation component 20 with a thickness of 2 mm to 3 mm is required between adjacent battery packs 10. This balances the reliability and energy density of the battery device 100. Similarly, in embodiments where the pouch battery cell 12 is constructed as a ternary lithium battery and the total internal capacity of the battery pack 10 is greater than 1 kWh, a heat insulation component 20 with a thickness of 3 mm to 4 mm is required between adjacent battery packs 10. This makes the thickness of the heat insulation component 20 more reasonable, thus balancing the energy density of the battery device 100.

[0125] In other words, compared to traditional prismatic battery cells, pouch cell 12 has higher packing efficiency and higher energy density within a single battery pack 10. However, as the number of pouch cells 12 inside the battery pack 10 increases, it is difficult to achieve thermal isolation between adjacent battery packs 10 using only the casing 11. Therefore, a heat insulation component 20 is further installed between adjacent battery packs 10. However, the heat generated when a pouch cell 12 experiences thermal runaway differs between different battery systems. For example, in the lithium iron phosphate battery system, the heat generated when a pouch cell 12 experiences thermal runaway is lower, while in the ternary lithium battery system, the heat generated when a pouch cell 12 experiences thermal runaway is higher. Therefore, for the same capacity, the thickness of the heat insulation component 20 between battery packs 10 is thicker in the ternary lithium battery system and relatively thinner in the lithium iron phosphate battery system. Under the same battery system, as the capacity increases, the thickness of the heat insulation component 20 is reasonably increased, but does not exceed an upper limit, such as 3mm for lithium iron phosphate batteries and 4mm for ternary lithium batteries.

[0126] It should be noted that two battery packs 10 can be installed in the sealed space of a simulated battery device. The two battery packs 10 have the same internal charge, and one of the battery packs 10 is subjected to thermal runaway (e.g., triggered by a short circuit), while the other battery pack 10 remains in a normal state. No heat insulation component 20 is installed between adjacent battery packs 10, or heat insulation components 20 of different thicknesses are installed sequentially. Based on national standards, a threshold for the allowable duration of thermal runaway in one battery pack 10 leading to thermal runaway in the other battery pack 10 is set (e.g., GB). The national standard 38031 requires that the battery device 100 should not catch fire within five minutes after the thermal runaway of a single battery cell. Based on this, an allowable time threshold of 5 minutes can be set. Then, it can be determined whether the time taken for thermal runaway to occur in a normal state between adjacent battery packs 10 reaches or exceeds the allowable time threshold, so as to determine the thermal protection effect between adjacent battery packs 10. This will determine whether a heat insulation component 20 needs to be set for battery packs 10 with different capacities. If a heat insulation component 20 needs to be set, the thickness of the heat insulation component 20 can be further determined by testing.

[0127] See the table below. The table shows the heat insulation effect of battery cells of the same size but different energy systems, different total capacities within a single battery pack 10, and heat insulation components 20 of different thicknesses between adjacent battery packs 10.

[0128] It should be noted that the test conditions are as follows: a heat insulation component 20 is installed between two adjacent battery packs 10; two battery packs 10 with the same capacity are selected (e.g., 0.5 kWh, 1 kWh, etc.); one battery pack 10 is made to experience thermal runaway while the other battery pack 10 does not; and the heat insulation component 20 is installed or not installed between the two battery packs 10 (e.g., measuring the thermal runaway time under a total capacity of 1.4 kWh, a single lithium iron phosphate battery cell, and a 1.2 mm thick heat insulation component); and the duration of thermal runaway in the other battery pack 10 is measured. The protection effect is defined based on the allowable duration threshold. For example, exceeding the allowable duration threshold by 1 minute is defined as excellent protection effect, equal to the allowable duration threshold is defined as good protection effect, less than the allowable duration threshold by 1 minute is defined as poor, and less than the allowable duration threshold by 2 minutes is defined as extremely poor. Both poor and extremely poor indicate that the protection effect is unqualified.

[0129] As shown in the table, in the embodiment where the soft-pack battery cell 12 is constructed as a lithium iron phosphate battery cell, when the total capacity is below 0.5 kWh, no heat insulation component 20 is required. When the total capacity is in the range of 0.5 kWh to 1 kWh, a heat insulation component 20 of 1 mm to 2 mm is sufficient to provide good protection. When the total capacity is greater than 1 kWh, a heat insulation component 20 of greater than 2 mm is required. In the embodiment where the soft-pack battery cell 12 is constructed as a ternary lithium battery cell, when the total capacity is below 0.5 kWh, no heat insulation component 20 is required. When the total capacity is in the range of 0.5 kWh to 1 kWh, a heat insulation component 20 of 1 mm to 3 mm is sufficient to provide good protection. When the total capacity is greater than 1 kWh, a heat insulation component 20 of greater than 3 mm is required.

[0130] In other words, as the total power consumption increases, the thickness of the insulation component 20 should be increased accordingly.

[0131] In this way, on the one hand, different thicknesses of the heat insulation component 20 can be set for battery cells with different energy systems, so that the reliability of the battery device 100 with different energy systems is higher. On the other hand, for battery cells with the same energy system, as the charge in the battery pack 10 increases, the thickness of the heat insulation component 20 also increases, which can improve the stability of the heat insulation component 20, ensure the reliability of the battery device 100, and allow for reasonable setting of the thickness of the heat insulation component 20 to take into account the energy density of the battery device 100.

[0132] As shown in FIG2, this application provides a battery device 100, including: a housing 30 and a battery pack 10. The battery pack 10 is at least one, and the battery pack 10 includes: at least one soft-pack battery cell 12 as described in the above embodiments and a cover shell 11. At least one side surface of the cover shell 11 has a pressure relief portion 1111.

[0133] The housing 30 has an accommodating space, and one or more battery packs 10 are disposed in the accommodating space. Each battery pack 10 has one or more pouch battery cells 12 disposed inside the casing 11, and the pouch battery cells 12 are constructed as described above using a flexible casing 121.

[0134] The casing 11 is used to cover at least one of the plurality of circumferential surfaces 1212 and two side surfaces 1211 of the pouch battery cell 12. A weak portion 1213 is provided on at least one circumferential surface 1212 of the pouch battery cell 12. At least one side of the casing 11 is formed with a pressure relief portion 1111, such as the pressure relief portion 1111 being opposite to the weak portion 1213, or the pressure relief portion 1111 being located on a first surface of the casing 11, while the weak portion 1213 is opposite to a second surface of the casing 11, and the first surface and the second surface are adjacent.

[0135] According to the battery device 100 of this application embodiment, by providing a pressure relief part 1111 on the casing 11 that cooperates with the weak part 1213, when the soft-pack battery cell 12 experiences thermal runaway, the high-temperature gas flow discharged through the weak part 1213 can be further released outward through the pressure relief part 1111. In order to improve the reliability of the battery device 100, the cooperation between the weak part 1213 and the pressure relief part 1111 enables the directional discharge of the high-temperature gas flow.

[0136] According to some embodiments of this application, the cover shell 11 includes a first plate 111 and a second plate 112 located on both sides of the first plate 111. A pressure relief portion 1111 is formed on the first plate 111, and a weak portion 1213 is at least partially opposite to the pressure relief portion 1111.

[0137] The first plate 111 and the second plates 112 located on both sides of the first plate 111 define a generally U-shaped cover shell 11, such that the first plate 111 of the cover shell 11 can be opposite to one circumferential surface 1212 of the soft-pack battery cell 12, while the two second plates 112 can be opposite to the two side surfaces 1211 of the soft-pack battery cell 12 respectively, and the weak portion 1213 formed on the circumferential surface 1212 can be at least partially opposite to the pressure relief portion 1111 formed on the first plate 111.

[0138] The weak portion 1213 and the pressure relief portion 1111 are at least partially opposite each other, meaning that the weak portion 1213 formed on the circumferential surface 1212 projects toward the first plate 111 and the projected outline at least partially overlaps with the outline of the pressure relief portion 1111.

[0139] In this way, on the one hand, the gas and fire generated after thermal runaway of the pouch cell 12 can be discharged in a directional manner, achieving orderly discharge to reduce damage, especially secondary damage. On the other hand, the connection path between the weak part 1213 and the pressure relief part 1111 is shorter, which can achieve rapid discharge while the gas and fire flow stays inside the casing 11 for a shorter time, thus having less impact on other pouch cells 12 around the thermally runaway pouch cell 12. It can also further reduce the spread rate of thermal runaway and improve the reliability of the battery pack 10 and the battery device 100.

[0140] According to some embodiments of this application, the second plate 112 is opposite to the side 1211, and the projected outline area of ​​the second plate 112 toward the side 1211 of the flexible shell 121 is less than or equal to the area of ​​the side 1211.

[0141] The circumferential surface 1212 is defined as including a first surface and a second surface opposite to it. The first surface is opposite to the first plate 111, and the second surface is disposed away from the first plate 111 and is used to connect to the housing 30. The two sides of the first surface and the second surface are the two side surfaces 1211 of the soft-pack battery cell 12, and the two ends of the first surface and the second surface are the other two circumferential surfaces 1212 of the soft-pack battery cell 12. The second plate 112 is opposite to the side surface 1211 to limit the soft-pack battery cell 12 in the direction of the second plate 112. The area of ​​the surface of the second plate 112 opposite to the side surface 1211 can be less than or equal to the area of ​​the side surface 1211.

[0142] In some embodiments, the size of the second plate 112 is the same as the size of the side 1211. In other embodiments, the size of the second plate 112 is smaller than the size of the side 1211. On the one hand, this can avoid the second plate 112 being too large, which would prevent the second side from being connected to the housing 30. This can improve the stability and reliability of the battery pack 10 within the housing 30. On the other hand, the second plate 112 can use less material, which can also reduce the material cost of the battery pack 10 and the battery device 100.

[0143] As shown in Figures 4 and 5, according to some embodiments of this application, the casing 11 includes: a first plate 111 and a second plate 112 located on both sides of the first plate 111 in a first direction, the second plate 112 being opposite to the soft-pack battery cell 12 in the first direction, and the heat insulation member 20 being connected to the second plate 112.

[0144] The second plate 112 is used to connect with the heat insulation component 20, so that the heat insulation component 20 can face the side 1211 of the soft-pack battery cell 12, so that the area of ​​the relative region between the heat insulation component 20 and the soft-pack battery cell 12 is larger, and the heat insulation effect of the heat insulation component 20 can be further improved.

[0145] The end face of the second plate 112 away from the first plate 111 is connected to the bottom plate 31 through the adhesive layer 32, which can also improve the connection strength between the cover shell 11 and the box 30. The heat on the cover shell 11 can also be transferred to the cold plate through the adhesive layer 32, which can improve the heat dissipation efficiency and heat dissipation effect of the battery pack 10.

[0146] As shown in Figures 3 and 4, according to some embodiments of this application, the second plate 112 forms an opening at one end opposite to the first plate 111, and the cover shell 11 is connected to the housing 30 of the battery device 100 through the opening.

[0147] The bottom plate 31 of the housing 30 is connected to the second side of the soft-pack battery cell 12 through an adhesive layer 32, while the end face of the second plate 112 away from the first plate 111 is connected to the bottom plate 31, so as to fix the battery pack 10 on the housing 30 and improve the fixation stability and reliability of the battery pack 10.

[0148] Of course, in some embodiments, the adhesive layer 32 is also used for the connection and fixation between the base plate 31 and the second plate 112.

[0149] Referring to Figure 5, according to some embodiments of this application, the base plate 31 includes a cold plate, and the adhesive layer 32 is located between the cold plate and a plurality of soft-pack battery cells 12.

[0150] In some embodiments, the bottom plate 31 of the housing 30 is formed as a cold plate, and the cold plate is connected to the soft-pack battery cell 12 through an adhesive layer 32. In other embodiments, a cold plate is provided between the bottom plate 31 and the soft-pack battery cell 12, and the cold plate is connected to the soft-pack battery cell 12 through an adhesive layer 32.

[0151] The adhesive layer 32 is constructed as a structural adhesive, and the base plate 31 with a cold plate is connected to the soft-pack battery cell 12. Under the premise of ensuring that the battery pack 10 is stably and reliably fixed in the housing 30, the temperature of the battery pack 10 can also be regulated by the cold plate, so that the battery pack 10 can work at a suitable temperature. This can improve the working stability and reliability of the battery pack 10, reduce the probability of the battery pack 10 overheating, reduce the probability of thermal runaway of the battery pack 10, and thus improve the reliability of the battery pack 10 and even the battery device 100.

[0152] As shown in FIG5, according to some embodiments of the present application, the adhesive layer 32 includes an adhesive layer body 321 and an overflow portion 322. The overflow portion 322 is located on the side of the adhesive layer body 321 facing the plurality of pouch battery cells 12, and is located between adjacent pouch battery cells 12, and / or between the pouch battery cells 12 and the second plate 112.

[0153] When structural adhesive is used to connect and fix the soft-pack battery cell 12 to the cold plate, at least a portion of the adhesive layer 32 overflows between adjacent soft-pack battery cells 12 and / or between the second plate 112 and the soft-pack battery cell 12, forming an overflow portion 322. The overflow portion 322 not only increases the area between the adhesive layer 32 and the soft-pack battery cell 12 and between the adhesive layer 32 and the second plate 112, thereby improving the fixing stability and reliability of the battery pack 10 on the housing 30, but also fills the gaps between adjacent soft-pack battery cells 12 and between the soft-pack battery cell 12 and the second plate 112, thereby limiting the movement of the soft-pack battery cell 12 and the housing 11, reducing the movement of the battery pack 10 within the housing 30, and reducing the movement of the soft-pack battery cell 12 within the housing 11.

[0154] According to some embodiments of this application, when projected along a first direction, the projected outline of the pouch cell 12 is located within the projected outline range of the heat insulation member 20.

[0155] The outline dimensions of the heat insulation component 20 are greater than or equal to the outline dimensions of the soft-pack battery cell 12, so as to improve the heat insulation effect of the heat insulation component 20.

[0156] As shown in Figures 4 and 5, according to some embodiments of this application, the first plate 111 is spaced apart from the side of the circumferential surface 1212 with a weak portion 1213 to define an exhaust passage a.

[0157] In this way, the high-temperature gas flow generated after the weak part 1213 ruptures can be released to the exhaust channel a first, and after being initially buffered by the exhaust channel a, it can be discharged through the pressure relief part 1111. This can reduce the pressure of the high-temperature gas flow after it flows out of the pressure relief part 1111, thereby reducing the impact and damage after the thermal runaway of the soft-pack battery cell 12.

[0158] According to some embodiments of this application, the first plate 111 is constructed as a flat plate or an arc plate.

[0159] In some embodiments, the first plate 111 is constructed as a flat plate, and in other embodiments, the first plate 111 is constructed as an arc-shaped plate.

[0160] According to some embodiments of this application, there are multiple pressure relief sections 1111, and the multiple pressure relief sections 1111 are spaced apart in the length direction and / or width direction of the first plate 111.

[0161] Therefore, each of the multiple weak points 1213 on each pouch cell 12 can have a corresponding pressure relief part 1111, so that the high-temperature gas flow buffered by the exhaust channel a can be directly discharged through the corresponding pressure relief part 1111, thereby increasing the discharge speed and reducing the residence time of the high-temperature gas flow in the exhaust channel a during the discharge process, thereby reducing the spread speed of thermal runaway between adjacent pouch cells 12 in the battery pack 10 and improving the reliability of the battery pack 10.

[0162] According to some embodiments of this application, the casing 11 is constructed as an aluminum casing or a stainless steel casing.

[0163] In some embodiments, the casing 11 is constructed as an aluminum casing, and in other embodiments, the casing 11 is constructed as a stainless steel casing, so that the temperature resistance and structural strength of the casing 11 are much higher than those of the flexible casing. By using the casing 11 with a certain structural strength and rigidity to support and protect the soft-pack battery cell 12 outside the soft-pack battery cell 12, the structural strength of the battery pack 10 can be improved, the thermal runaway propagation rate between adjacent battery packs 10 can be reduced, and the reliability of the battery device 100 can be improved.

[0164] Referring to the accompanying drawings, the soft-pack battery cell 12 of this embodiment is constructed as a soft-pack battery cell 12, with electrode assembly 122 disposed within a flexible outer shell 121. The flexible outer shell 121 has a weak portion 1213 formed on at least its circumferential surface 1212. The battery pack 10 includes at least one soft-pack battery cell 12 of this embodiment, and the pressure relief portion 1111 on the first plate 111 of the covering shell 11 is at least partially opposite to the weak portion 1213. The second plate 112 is opposite to the side surface 1211 of the flexible outer shell 121. The housing 30... The base plate 31 is constructed as a cold plate, or a cold plate is provided on top of the base plate 31. The cold plate is connected to the soft-pack battery cell 12 through an adhesive layer 32. The adhesive layer 32 overflows from the adhesive layer 32 to the space between adjacent soft-pack battery cells 12, and / or between the soft-pack battery cell 12 and the second plate 112. A heat insulation component 20 is provided between adjacent battery packs 10. The heat insulation component 20 is connected to at least one of the base plate 31 and the top plate of the housing 30. The heat insulation component 20 and the second plate 112 can also be fixed by structural adhesive, screw structure, snap-fit ​​structure, etc.

[0165] According to some embodiments of this application, the soft-pack battery cell 12 is any one of a lithium iron phosphate battery cell, a ternary lithium battery cell, and a solid-state battery cell.

[0166] In other words, in some embodiments, the pouch battery cell 12 is constructed as a lithium iron phosphate battery, in some embodiments, the pouch battery cell 12 is constructed as a ternary lithium battery cell, and in some embodiments, the pouch battery cell 12 is constructed as a solid-state battery cell.

[0167] Solid-state battery cells can be, but are not limited to, polymer solid-state battery cells, oxide solid-state battery cells, sulfide solid-state battery cells, halide solid-state battery cells, etc. Solid-state battery cells can also be semi-solid-state battery cells or all-solid-state battery cells.

[0168] In the above technical solutions, in the embodiments of this application that are constructed as lithium iron phosphate battery cells, the reliability of the pouch battery cells can be improved and the cycle life of the pouch battery cells can be extended. In the embodiments of this application that are constructed as ternary lithium battery cells, the energy density of the pouch battery cells can be improved and the driving range can be increased. In the embodiments of this application that are constructed as solid-state pouch battery cells, not only the energy density can be improved, but also the reliability can be improved.

[0169] According to some embodiments of this application, when the pouch battery cell 22 is a lithium iron phosphate (LiFeO4) battery cell, the ratio of positive electrode active material, positive electrode binder, and positive electrode conductive agent in the positive electrode material of the pouch battery cell 22 is 96:1-3:1-3; when the pouch battery cell 22 is a ternary lithium battery cell, the ratio of positive electrode active material, positive electrode binder, and positive electrode conductive agent in the positive electrode material of the pouch battery cell 22 is 96:2-3:1-2.

[0170] It is understandable that when the pouch cell 22 is a lithium iron phosphate battery cell, the positive electrode material of the pouch cell 22 has the following proportions: 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.).

[0171] For example, when the pouch cell 22 is a lithium iron phosphate battery cell, the positive electrode active material is LFP (which can refer to 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, meaning that the total weight of the positive electrode active material is divided into 100 parts, with LFP accounting for 96 parts, PVDF accounting for 2 parts, and conductive carbon black also accounting for 2 parts. The weight unit of the positive electrode active material can be grams.

[0172] When the pouch cell 22 is a ternary lithium battery cell, in the positive electrode material of the pouch cell 22, the positive electrode active material accounts for 96 parts of the total weight of the positive electrode material, the binder accounts for 2 to 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 to 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.). The ternary lithium battery cell can be, but is not limited to, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, etc.

[0173] For example, the ternary material of the ternary battery cell can be an octet LiNi. 0.8 Co 0.1 Mn 0.1 The weight ratio of O2, positive electrode active material, binder, and conductive agent is 96:2.5:1.5, meaning the total weight of the positive electrode material is divided into 100 parts. (This refers to the octet LiNi...) 0.8 Co 0.1 Mn 0.1 The composition of O2 is 96 parts, the composition of adhesive is 2.5 parts, and the composition of conductive agent is 1.5 parts.

[0174] In the above technical solutions, when the pouch battery cell 22 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 within a limited electrode assembly. This is beneficial for increasing the capacity and energy density of the battery device 100, enabling the lithium iron phosphate battery cell to output higher power while maintaining a relatively small volume and weight, meeting the application scenarios with certain energy density requirements. Using the above-mentioned range for the amount of binder and conductive agent can reduce the cost of auxiliary materials, thereby reducing the overall cost of the battery device 100. When the pouch battery cell 22 is a ternary battery cell, due to the relatively complex structure and surface properties of ternary materials, using the above-mentioned proportions of positive electrode active material, binder, and conductive agent helps to ensure good adhesion between 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. This helps to reduce the risk of active material detachment and electrode pulverization during charging and discharging, and extends the cycle life of the battery device 100.

[0175] This application proposes an electrical device 200, including: the battery device 100 in the above embodiments.

[0176] Furthermore, as shown in Figure 1, the electrical equipment 200 can be a vehicle, and the battery device 100 can be integrated into the vehicle chassis. That is, the vehicle body structure is a split body, with the upper body and the integrated intelligent chassis assembled together, and the battery device 100 forming part of the integrated intelligent chassis. In this way, the top plate of the box 30 can also participate in defining the vehicle floor, which can save the meaningless stacking of multiple layers of sheet metal, reduce material costs, and make the space occupation of the chassis more reasonable. The space inside the chassis for accommodating the battery device 100 is larger and the energy density is higher.

[0177] It should also be noted that in the aforementioned simulated thermal runaway test, both ternary lithium and lithium iron phosphate materials can be prepared according to the above formula, which will not be elaborated here.

[0178] It is understandable that the electrical equipment 200 is constructed as a vehicle, that is, the vehicle uses the aforementioned battery device 100. The battery device 100 has higher energy density and higher reliability, which can improve the vehicle's driving range and driving safety.

[0179] Other configurations and operations of the soft-pack battery cell 12, battery device 100, and electrical equipment 200 according to the embodiments of this application are known to those skilled in the art and will not be described in detail here.

[0180] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0181] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A battery device, characterized by, include: Multiple battery packs (10) are arranged sequentially along a first direction. Each battery pack (10) includes a casing (11) and at least one soft-pack battery cell (12), which is disposed inside the casing (11). Among the plurality of battery packs (10), at least two adjacent battery packs (10) are provided with a heat insulation element (20).

2. The battery device according to claim 1, characterized by The heat insulation element (20) is provided between any two adjacent battery packs (10).

3. The battery device according to claim 1 or 2, characterized by, The thickness of the heat insulation component (20) in the first direction is 1 mm to 4 mm.

4. The battery device of claim 3, wherein The soft-pack battery cell (12) is constructed as a lithium iron phosphate battery, the total charge inside the battery pack (10) is less than or equal to 1 kWh, and the thickness of the heat insulation component (20) is 1 mm to 2 mm.

5. The battery device of claim 3, wherein The soft-pack battery cell (12) is constructed as a lithium iron phosphate battery, the total capacity inside the battery pack (10) is greater than 1 kWh, and the thickness of the heat insulation component (20) is 2 mm to 3 mm.

6. The battery device of claim 3, wherein The soft-pack battery cell (12) is constructed as a ternary lithium battery, the total charge inside the battery pack (10) is less than or equal to 1 kWh, and the thickness of the heat insulation component (20) is 2 mm to 3 mm.

7. The battery device of claim 3, wherein The soft-pack battery cell (12) is constructed as a ternary lithium battery, the total charge inside the battery pack (10) is greater than 1 kWh, and the thickness of the heat insulation component (20) is 3 mm to 4 mm.

8. The battery device according to claim 1 or 2, characterized by The casing (11) includes: a first plate (111) and a second plate (112) located on both sides of the first plate (111) in the first direction, the second plate (112) being opposite to the soft-pack battery cell (12) in the first direction, and the heat insulation member (20) being connected to the second plate (112).

9. The battery device of claim 8, wherein, The second plate (112) has an opening at one end opposite to the first plate (111), and the cover shell (11) is connected to the housing (30) of the battery device through the opening.

10. The battery device of claim 9, wherein, The housing (30) has a bottom plate (31), and the end face of the second plate (112) away from the first plate (111) is connected to the bottom plate (31) by an adhesive layer (32).

11. The battery device of claim 10, wherein, The base plate (31) is constructed as a cold plate, and / or the base plate (31) is provided with a cold plate on the side facing the plurality of soft-pack battery cells (12), and the adhesive layer (32) is located between the cold plate and the plurality of soft-pack battery cells (12).

12. The battery device of claim 10, wherein, The adhesive layer (32) includes an adhesive layer body (321) and an overflow portion (322), wherein the overflow portion (322) is located on the side of the adhesive layer body (321) facing the plurality of pouch battery cells (12), and is located between adjacent pouch battery cells (12), and / or between the pouch battery cells (12) and the second plate (112), and / or between the second plate (112) and the heat insulation member (20).

13. The battery device of claim 8, wherein, The pouch cell (12) includes: a flexible shell (121) and an electrode assembly (122) disposed within the flexible shell (121). The flexible shell (121) has a side surface (1211) opposite to the large surface of the electrode assembly (122) and a circumferential surface (1212) avoiding the large surface. The side surface (1211) and / or the circumferential surface (1212) are provided with a weak portion (1213). The covering shell (11) has a pressure relief portion (1111) at least partially opposite to the weak portion (1213). The pressure relief portion (1111) is formed on the first plate (111).

14. The battery device according to claim 1 or 2, wherein Projecting along the first direction, the projected outline of the soft-pack battery cell (12) lies within the projected outline range of the heat insulation element (20).

15. The battery device of claim 1, wherein, The insulation component (20) is constructed as one or more of mica board, foam board, and aerogel board.

16. The battery device of any one of claims 1-15, wherein, The soft-pack battery cell (12) is any one of lithium iron phosphate battery cell, ternary lithium battery cell, and solid-state battery cell.

17. The battery device of claim 16, wherein, The soft-pack battery cell (12) is a lithium iron phosphate battery cell. In the positive electrode material of the soft-pack battery cell (12), the ratio of positive electrode active material, positive electrode binder and positive electrode conductive agent is 96:1-3:1-3. The soft-pack battery cell (12) is a ternary lithium battery cell. In the positive electrode material of the soft-pack battery cell (12), the ratio of positive electrode active material, positive electrode binder and positive electrode conductive agent is 96:2-3:1-2.

18. An electrical device, comprising: include: The battery device according to any one of claims 1-17.

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