Battery device and electric device

Abstract

The utility model provides a battery device and a power utilization device. The battery device comprises a box body, a constant pressure mechanism, a plurality of solid-state batteries and a plurality of expansion pieces, the plurality of solid-state batteries are arranged along a first direction and are accommodated in the box body; the multiple expansion parts are arranged in the first direction, at least one solid-state battery is arranged between every two adjacent expansion parts, expansion cavities are formed in the expansion parts, and the expansion cavities are used for containing fluid media. The constant pressure mechanism is connected with the expansion part, and the constant pressure mechanism is configured to discharge the fluid medium in the expansion cavity when the internal pressure value of the expansion cavity reaches a threshold value and stop discharging the fluid medium in the expansion cavity when the internal pressure value of the expansion cavity is lower than the threshold value. The battery device reduces the risk that the solid-state battery is damaged due to the fact that the extrusion force of the expansion piece for extruding the solid-state battery is too large, and the reliability of the battery device is improved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of batteries, in particular to a battery device and a power utilization device. BACKGROUND

[0002] Energy saving and emission reduction is the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their energy saving and environmental protection advantages. For electric vehicles, battery technology is an important factor for their development.

[0003] Battery devices are widely used in portable electronic devices, electric vehicles, electric tools, unmanned aerial vehicles, energy storage devices and other fields. As the demand for batteries increases, higher reliability requirements are placed on battery devices. Therefore, how to improve the reliability of battery devices is a problem to be solved in battery technology. UTILITY MODEL CONTENT

[0004] The application provides a battery device and a power utilization device, which can improve the reliability of the battery device.

[0005] In a first aspect, the application provides a battery device, comprising a box body, a constant pressure mechanism, a plurality of solid-state batteries and a plurality of expansion pieces; the plurality of solid-state batteries are arranged along a first direction, and the plurality of solid-state batteries are accommodated in the box body; the plurality of expansion pieces are arranged along the first direction, at least one solid-state battery is arranged between two adjacent expansion pieces, the expansion piece has an expansion cavity, and the expansion cavity is used to accommodate a fluid medium; the constant pressure mechanism is connected with the expansion piece, and the constant pressure mechanism is configured to release the fluid medium in the expansion cavity when the internal pressure value of the expansion cavity reaches a threshold value, and stop releasing the fluid medium in the expansion cavity when the internal pressure value of the expansion cavity is lower than the threshold value.

[0006] In the above technical solution, at least one solid-state battery is arranged between two adjacent expansion pieces. On the one hand, the expansion piece can limit the position of the solid-state battery, so that the position of the solid-state battery is more stable. On the other hand, the expansion of the solid-state battery will increase the volume of the solid-state battery. The expansion of the solid-state battery causes the internal pressure of the solid-state battery to increase. The constant pressure mechanism is connected with the expansion piece. The constant pressure mechanism can release the fluid medium in the expansion cavity when the internal pressure of the expansion cavity reaches a threshold value, and stop releasing the fluid medium in the expansion cavity when the internal pressure of the expansion cavity is lower than the threshold value. In this way, the expansion piece can provide a relatively stable extrusion force to the solid-state battery, so as to reduce the risk of damage to the solid-state battery caused by excessive extrusion force of the expansion piece on the solid-state battery, and improve the reliability of the battery device.

[0007] In some embodiments, the constant pressure mechanism comprises a switch unit connected to the expansion member, the switch unit being configured to open when the internal pressure value of the expansion cavity reaches the threshold value and to close when the internal pressure value of the expansion cavity is below the threshold value. By setting the switch unit to open when the internal pressure value of the expansion cavity reaches the threshold value and to close when the internal pressure value of the expansion cavity is below the threshold value, the control of the amount of fluid medium in the expansion member can be achieved through the switch unit, reducing the difficulty of controlling the internal pressure value of the expansion cavity.

[0008] In some embodiments, the constant pressure mechanism further comprises a detection unit for detecting the internal pressure value of the expansion member, the switch unit being responsive to the detection unit to open when the internal pressure value of the expansion member reaches the threshold value and to close when the internal pressure value of the expansion member is below the threshold value. In this way, the detection unit can drive the switch unit to open when the internal pressure value of the expansion member reaches the threshold value and to close when the internal pressure value of the expansion member is below the threshold value, thereby maintaining the internal pressure value of the expansion member in a relatively stable range, reducing the risk of damage to the solid-state battery due to excessive internal pressure. The switch unit is convenient to operate by responding to the detection unit to release the internal pressure of the expansion cavity, reducing the difficulty of regulating the internal pressure of the expansion cavity.

[0009] In some embodiments, the constant pressure mechanism further comprises a flow supply assembly connected to the plurality of expansion members, the flow supply assembly being configured to supply fluid medium into the expansion cavity. By supplying fluid medium into the expansion cavity through the flow supply assembly, the internal pressure of the expansion cavity can be increased, thereby improving the fixing effect of the expansion member on the solid-state battery, making the position of the solid-state battery more stable.

[0010] In some embodiments, the flow supply assembly comprises a storage unit and a pumping unit; the storage unit is used to store fluid medium; the pumping unit is connected to the storage unit and the expansion member, and the pumping unit is configured to pump the fluid medium in the storage unit into the expansion cavity. By pumping the fluid medium stored in the storage unit into the expansion cavity through the pumping unit, the difficulty of supplying fluid medium into the expansion cavity by the flow supply assembly is reduced.

[0011] In some embodiments, the storage unit is used to store the fluid medium released from the expansion cavity through the switch unit. In this way, the fluid medium in the expansion cavity can flow into the storage unit, and the fluid medium in the storage unit can also flow into the expansion cavity. On the one hand, the fluid medium can be recycled, reducing the cost of fluid use; on the other hand, the fluid circulation in the expansion cavity can be achieved, and in the process of fluid circulation, the heat of the solid-state battery can be carried away by the fluid, thereby reducing the risk of thermal runaway of the solid-state battery and improving the reliability of the battery device.

[0012] In some embodiments, the constant pressure mechanism further comprises an outflow pipeline and an inflow pipeline; the outflow pipeline is connected to the storage unit and the plurality of expansion members, and the switch unit is arranged on the outflow pipeline; the inflow pipeline is connected to the pumping unit and the plurality of expansion members. By arranging the outflow pipeline and the inflow pipeline, a closed loop can be formed between the constant pressure mechanism and the expansion members, so that the fluid medium can be exchanged between the expansion members and the constant pressure mechanism, which is conducive to temperature control of the solid-state battery.

[0013] In some embodiments, in a projection plane perpendicular to the first direction, the orthographic projection of the solid-state battery is located within the orthographic projection of the expansion member. On the one hand, the risk of the solid-state battery contacting the two sides of the expansion member along the first direction can be reduced, and the reliability of the battery device can be improved; on the other hand, the contact area of the expansion member and the solid-state battery can be increased, so that the stress on the surface of the solid-state battery in contact with the expansion member is more uniform, and the risk of damage to the solid-state battery is reduced.

[0014] In some embodiments, in a projection plane perpendicular to the first direction, the orthographic projection of the expansion member is greater than the orthographic projection of the solid-state battery. In this way, the risk of the solid-state battery contacting the two sides of the expansion member along the first direction can be further reduced, and the support of the expansion member to the solid-state battery can be more stable.

[0015] In some embodiments, the solid-state battery comprises a shell and an electrode assembly, the electrode assembly is contained in the shell, the electrode assembly comprises a solid-state electrolyte layer and a plurality of electrode sheets, along the first direction, at least part of the solid-state electrolyte layer is arranged between two adjacent electrode sheets, the electrode sheet comprises an active material layer, and in the two adjacent electrode sheets, the polarities of the two active material layers facing the solid-state electrolyte layer between the two adjacent electrode sheets are opposite. In this way, when the electrode assembly expands along the first direction, the solid-state battery extrudes the expansion member along the first direction, and the expansion member discharging the fluid medium can reduce the extrusion force of the solid-state battery along the first direction, thereby reducing the risk of damage to the electrode assembly due to expansion along the first direction and improving the reliability of the battery device.

[0016] In some embodiments, the plurality of electrode sheets comprises a positive electrode sheet and a negative electrode sheet, and along the first direction, the solid-state electrolyte layer is arranged between the positive electrode sheet and the negative electrode sheet. In this way, the solid-state electrolyte layer, the positive electrode sheet and the negative electrode sheet are arranged in layers along the first direction, the electrode assembly is easy to expand along the first direction, and by discharging the fluid medium in the expansion cavity, the internal pressure of the solid-state battery can be reduced, thereby reducing the risk of damage to the solid-state battery.

[0017] In some embodiments, the electrode sheet further comprises a current collector, and along the first direction, the opposite surfaces of the current collector are both provided with active material layers, and the polarities of the active material layers on the opposite surfaces of the current collector are opposite. In this way, the electrode assembly is easy to expand along the first direction, and by discharging the fluid medium in the expansion cavity, the internal pressure of the solid-state battery can be reduced, thereby reducing the risk of damage to the solid-state battery.

[0018] In some embodiments, the shell has a first outer surface, the first outer surface being a surface with a largest outer surface area of the shell, and the first outer surface is perpendicular to the first direction. By arranging the first outer surface to be perpendicular to the first direction, the first outer surface can face the expansion member, thereby increasing the contact area between the expansion member and the solid-state battery, making the position of the expansion member and the solid-state battery more stable, and reducing the pressure between the solid-state battery and the expansion member, reducing the risk of damage to the solid-state battery or the expansion member.

[0019] In some embodiments, the box body includes two limiting portions oppositely arranged along the first direction, and the plurality of expansion members and the plurality of solid-state batteries are located between the two limiting portions along the first direction. By arranging the expansion members and the solid-state batteries between the two limiting portions, the position of the expansion members and the solid-state batteries in the box body can be more stable, and the assembly of the expansion members and the solid-state batteries can be more convenient.

[0020] In some embodiments, along the first direction, the two expansion members located at the two ends of the plurality of solid-state batteries respectively abut against the two limiting portions. By arranging the expansion members to contact the limiting portions, the risk of damage to the solid-state battery due to contact with the limiting portions can be reduced, and the expansion members can also buffer the solid-state battery, further reducing the risk of damage to the solid-state battery and improving the reliability of the battery device.

[0021] In some embodiments, the threshold value is 0.5 MPa-5 MPa. When the threshold value is greater than or equal to 0.5 MPa, the expansion member can provide stable support force to the solid-state battery, improving the structural stability of the solid-state battery in the box body; when the threshold value is less than or equal to 5 MPa, the expansion member releases the fluid medium when the internal pressure reaches the threshold value, so as to reduce the internal pressure of the expansion member, thereby reducing the extrusion force of the expansion member against the solid-state battery and reducing the internal pressure of the solid-state battery, reducing the risk of damage to the solid-state battery and improving the reliability of the battery device; therefore, when the threshold value is 0.5 MPa-5 MPa, the support of the expansion member to the solid-state battery and the reduction of the internal pressure of the solid-state battery can be considered, the structural stability of the solid-state battery is improved, and the reliability of the battery device is improved.

[0022] In some embodiments, the threshold value is 2 MPa. In this way, the expansion member can release the fluid medium when the internal pressure of the expansion cavity reaches 2 MPa, so as to reduce the internal pressure of the expansion cavity, thereby reducing the extrusion force of the expansion member against the solid-state battery, further reducing the hindering effect of the expansion member on the expansion of the solid-state battery, reducing the risk of damage to the solid-state battery, and improving the reliability of the battery device.

[0023] In a second aspect, the embodiments of the present application provide a power utilization device, which includes the battery device provided by any one of the embodiments of the first aspect. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced as follows. It should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be considered as a limitation to the scope. Other related drawings can also be obtained by those of ordinary skill in the art without any creative effort.

[0025] Figure 1 Structural schematic diagram of a vehicle provided for some embodiments of the present application;

[0026] Figure 2 Exploded view of a battery device provided for some embodiments of the present application;

[0027] Figure 3 Exploded view of a solid-state battery provided for some embodiments of the present application;

[0028] Figure 4 Structural schematic diagram of a battery device provided for some embodiments of the present application;

[0029] Figure 5 Assembly diagram of an expansion member and a constant pressure mechanism provided for some embodiments of the present application;

[0030] Figure 6 Assembly diagram of an expansion member and a constant pressure mechanism provided for some embodiments of the present application;

[0031] Figure 7 Assembly diagram of an expansion member and a constant pressure mechanism provided for some embodiments of the present application;

[0032] Figure 8 Structural schematic diagram of a battery device provided for some embodiments of the present application;

[0033] Figure 9 Structural schematic diagram of a solid-state battery provided for some embodiments of the present application;

[0034] Figure 10 Structural schematic diagram of an electrode assembly provided for some embodiments of the present application.

[0035] Icon: 1-solid-state battery; 11-electrode assembly; 111-solid-state electrolyte layer; 112-pole piece; 1121-positive electrode current collector; 1122-positive electrode active material layer; 1123-negative electrode current collector; 1124-negative electrode active material layer; 1125-current collector; 11251-first surface; 11252-second surface; 12-outer shell; 121-shell; 122-end cover; 123-first outer surface; 13-electrode terminal;

[0036] 2-box body; 21-first box body; 22-second box body; 23-limiting portion; 24-first compartment; 25-second compartment;

[0037] 3 - expansion; 32 - inlet port; 33 - outlet port;

[0038] 4 - constant pressure mechanism; 41 - switch unit; 42 - detection unit; 43 - supply assembly; 431 - storage unit; 432 - pumping unit; 44 - outlet line; 45 - inlet line;

[0039] 10 - battery device; 20 - controller; 30 - motor; 100 - vehicle; X - first direction; Y - second direction. DETAILED DESCRIPTION

[0040] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0041] Unless otherwise defined, all technical and scientific terms used in the present application have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the terms used in the present application are only for the purpose of describing the specific embodiments of the present application and are not intended to limit the present application; the terms "include" and "have" and any variations thereof in the specification and claims of the present application and the above description of drawings are intended to cover non-exclusive inclusion. The terms "first", "second" and the like in the specification and claims of the present application and the above description of drawings are used to distinguish different objects, and are not intended to describe a particular order or primary and secondary relationship.

[0042] In the present application, the phrase "embodiments" means that the specific features, structures or characteristics described in connection with the embodiments can be included in at least one embodiment of the present application. The appearance of this phrase at various places in the specification does not necessarily mean the same embodiment, nor is it an independent or alternative embodiment to other embodiments.

[0043] In the present application, the term "and / or" is only a description of the association relationship between the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in the present application generally represents an "or" relationship between the front and rear associated objects.

[0044] In the embodiments of the present application, the same reference signs represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are only exemplary and should not constitute any limitation on the present application.

[0045] “Multiple” appearing in the present application means two or more (including two).

[0046] In the embodiments of the present application, the solid-state battery can be a secondary battery, which refers to a solid-state battery that can be activated by charging after discharging to continue to be used.

[0047] The solid-state battery includes, but is not limited to, 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.

[0048] The solid-state battery generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of the solid-state battery, active ions (such as lithium ions) are inserted and extracted between the positive electrode and the negative electrode. The separator is arranged between the positive electrode and the negative electrode, which can reduce the risk of short circuit of the positive and negative electrodes, and at the same time allow the active ions to pass through.

[0049] In some embodiments, the positive electrode can be a positive electrode tab, which can include a positive electrode current collector and a positive electrode active material arranged on at least one surface of the positive electrode current collector.

[0050] As an example, the positive electrode current collector has two opposite surfaces in the thickness direction of itself, and the positive electrode active material is arranged on any one or both of the two opposite surfaces of the positive electrode current collector.

[0051] As an example, the positive electrode current collector can adopt a metal foil or a composite current collector. For example, as a metal foil, aluminum with silver plating treatment on the surface, stainless steel with silver plating treatment on the surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium, etc. can be adopted. The composite current collector can include a high 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 high polymer material base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0052] As an example, the positive active material can include at least one of a lithium-containing phosphate, a lithium transition metal oxide, and a modified compound of each thereof. However, the present application is not limited to these materials, and other conventional materials that can be used as a positive active material of a solid-state battery can also be used. These positive active materials can be used alone only one or two or more of them can be used in combination. Among them, examples of the lithium-containing phosphate can include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (which can also be referred to as LFP)), a composite of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite of lithium manganese phosphate and carbon, lithium manganese iron phosphate, and a composite of lithium manganese iron phosphate and carbon. Examples of the lithium transition metal oxide can include, but are not limited to, at least one of lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3Mn 1 / 3 O2 (which can also be referred to as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O2 (which can also be referred to as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O2 (which can also be referred to as NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O2 (which can also be referred to as NCM 622 ), LiNi 0.8 Co 0.1 Mn 0.1 O2 (which can also be referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05 O2), and modified compounds thereof.

[0053] In some embodiments, the positive electrode can employ a foam metal. The foam metal can be a foam nickel, a foam copper, a foam aluminum, a foam alloy, or the like. When the foam metal is used as the positive electrode, the surface of the foam metal can not be provided with a positive active material, or of course can be provided with a positive active material. As an example, the foam metal can also be filled or / and deposited with a lithium source material, a potassium metal, or a sodium metal, the lithium source material being a lithium metal and / or a lithium-rich material.

[0054] In some embodiments, the negative electrode can be a negative electrode sheet, and the negative electrode sheet can include a negative current collector.

[0055] As an example, the negative current collector can employ a metal foil, a foamed metal, or a composite current collector. For example, as the metal foil, aluminum plated with silver on the surface, stainless steel plated with silver on the surface, stainless steel, copper, aluminum, nickel, a carbon electrode, carbon, nickel, or titanium, or the like can be employed. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or the like. 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, or the like) on a polymer material base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, or the like).

[0056] As an example, the negative electrode tab can include a negative current collector and a negative active material disposed on at least one surface of the negative current collector.

[0057] As an example, the negative current collector has two surfaces opposite in the thickness direction thereof, and the negative active material is disposed on either one or both of the two opposite surfaces of the negative current collector.

[0058] As an example, the negative active material can employ a negative active material for a solid-state battery known in the art. As an example, the negative active material can include at least one of artificial graphite, natural graphite, soft carbon, hard carbon, a silicon-based material, a tin-based material, lithium titanate, or the like. The silicon-based material can be selected from 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 be selected from 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 active material for a solid-state battery can also be used. These negative active materials can be used alone or in combination of two or more.

[0059] In some embodiments, the material of the positive current collector can be aluminum, and the material of the negative current collector can be copper.

[0060] In some embodiments, the separator is a solid-state electrolyte. The solid-state electrolyte is disposed between the positive electrode and the negative electrode, and functions to transport ions and separate the positive electrode and the negative electrode.

[0061] The solid-state electrolyte includes a polymer solid-state electrolyte, an inorganic solid-state electrolyte, and a composite solid-state electrolyte.

[0062] As an example, the polymer solid-state electrolyte can be a polyether (polyethylene oxide), a polysiloxane, a polycarbonate, a polyacrylonitrile, a polyvinylidene fluoride, a polymethyl methacrylate, a single-ion polymer, a polyionic liquid-lithium salt, cellulose, or the like.

[0063] As an example, the inorganic solid-state electrolyte can include one or more of an oxide solid-state electrolyte (crystalline perovskite, sodium superionic conductor, garnet, amorphous LiPON thin film), a sulfide solid-state electrolyte (crystalline lithium superionic conductor (lithium germanium phosphorous sulfide, argyrodite), amorphous sulfide), and a halide solid-state electrolyte, a nitride solid-state electrolyte, and a hydride solid-state electrolyte.

[0064] As an example, the composite solid-state electrolyte is formed by adding an inorganic solid-state electrolyte filler to a polymer solid-state electrolyte.

[0065] In some embodiments, the electrode assembly is a stacked structure.

[0066] As an example, a plurality of positive electrode tabs and a plurality of negative electrode tabs can be provided, respectively, and the plurality of positive electrode tabs and the plurality of negative electrode tabs can be alternately stacked.

[0067] As an example, a plurality of separators can be provided, respectively, between any adjacent positive electrode tab or negative electrode tab.

[0068] In some embodiments, the electrode assembly is provided with a tab, and the tab can lead current out of the electrode assembly. The tab includes a positive electrode tab and a negative electrode tab.

[0069] In some embodiments, the battery pack can include a housing. The housing is used to seal components such as the electrode assembly. The housing can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite shell), or an aluminum-plastic film, etc.

[0070] In some embodiments, the solid-state battery can include a housing. The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite shell), or an aluminum-plastic film, etc.

[0071] As an example, the solid-state battery can be a cylindrical solid-state battery, a prismatic solid-state battery, a pouch solid-state battery, or a solid-state battery of other shapes, and the prismatic solid-state battery includes a square shell solid-state battery, a blade-shaped solid-state battery, a multi-prismatic solid-state battery, such as a hexagonal prismatic solid-state battery, etc.

[0072] The battery apparatus mentioned in the embodiments of the present application can include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly can include a plurality of solid-state batteries connected in series, in parallel, or in a mixed connection through a busbar component.

[0073] In some embodiments, the battery cell assembly is typically formed by arranging a plurality of solid-state batteries; as an example, the battery cell assembly can be a battery module, which is formed by arranging and fixing a plurality of solid-state batteries into an independent module.

[0074] As an example, the battery module can be formed by bundling a plurality of solid-state batteries with a cable tie.

[0075] In some embodiments, the battery device can be a battery pack, which can include a box and one or more battery cell assemblies accommodated in the box.

[0076] As an example, the battery cell assembly can be a battery module, and the solid-state battery assembly can be accommodated in the box by fixing the battery module in the box.

[0077] As an example, the battery cell assembly can also be accommodated in the box by directly fixing a plurality of solid-state batteries in the box.

[0078] As an example, the box can include 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 cell assembly. Here, closed means covered or closed, which can be sealed or unsealed. The first box can be a top cover or a bottom plate.

[0079] As an example, the box can include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected with the frame, so that a closed space is formed inside the box to accommodate the battery cell assembly.

[0080] As an example, the box can be part of the chassis structure of the vehicle. For example, the top cover of the box can be at least part of the floor of the vehicle, or the frame of the box can be at least part of the cross beam and the longitudinal beam of the vehicle.

[0081] In some embodiments, the battery device refers to an energy storage device, which includes a box, at least one side of which is provided with a door. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0082] For the battery device, the battery device can generally include a box body and a plurality of solid-state batteries. The plurality of solid-state batteries are accommodated in the box body and arranged along a first direction. In order to reduce the risk of short circuit between the solid-state batteries and make the structure of the solid-state batteries in the box body more stable, a buffer pad can be arranged on both sides of the solid-state batteries along the first direction. The buffer pad can isolate the solid-state batteries arranged adjacent along the first direction, isolate the solid-state batteries and the box wall of the box body, and make the position of the solid-state batteries in the box body relatively stable, facilitating the use and transportation of the battery device. However, as the number of charging and discharging of the solid-state battery increases, the solid-state battery is prone to expand along the first direction to press the buffer pad. As the expansion amount of the solid-state battery increases, the deformation amount of the buffer pad also increases, and the pressing force of the buffer pad on the solid-state battery also increases. The reaction force of the buffer pad acting on the solid-state battery further increases the internal pressure of the solid-state battery, increasing the risk of damage to the solid-state battery and affecting the reliability of the battery device.

[0083] In view of this, the embodiments of the present application provide a battery device, which includes a box body, a constant pressure mechanism, a plurality of solid-state batteries and a plurality of expansion pieces. The plurality of solid-state batteries are arranged along a first direction, and the plurality of solid-state batteries are accommodated in the box body. The plurality of expansion pieces are arranged along the first direction, and at least one solid-state battery is arranged between adjacent two expansion pieces. The expansion piece has an expansion cavity for accommodating a fluid medium. The constant pressure mechanism is connected with the expansion piece, and the constant pressure mechanism is configured to release the fluid medium in the expansion cavity when the internal pressure value of the expansion cavity reaches a threshold value.

[0084] In such a battery device, by arranging at least one solid-state battery between adjacent two expansion pieces, on the one hand, the expansion piece can limit the position of the solid-state battery, making the position of the solid-state battery more stable. On the other hand, since the expansion of the solid-state battery will increase the volume of the solid-state battery, the expansion of the solid-state battery pressing the expansion piece will increase the internal pressure of the solid-state battery. By releasing the fluid medium when the internal pressure of the expansion cavity reaches the threshold value, the pressing force between the solid-state battery and the expansion piece is reduced, thereby relieving the internal pressure of the solid-state battery, and further reducing the risk of damage to the solid-state battery and improving the reliability of the battery device.

[0085] The following embodiments are described by taking a vehicle as an example for convenience of description.

[0086] Please refer to Figure 1 , Figure 1 The structure schematic diagram of the vehicle 100 provided by some embodiments of the present application is shown. The vehicle 100 is internally provided with a battery device 10, which can be arranged at the bottom, head or tail of the vehicle 100. The battery device 10 can be used for power supply of the vehicle 100, for example, the battery device 10 can be used as the operating power supply of the vehicle 100.

[0087] The vehicle 100 can further include a controller 20 and a motor 30, the controller 20 being configured to control the battery device 10 to supply power to the motor 30, for example, for power requirements of the vehicle 100 during startup, navigation, and travel.

[0088] In some embodiments of the present application, the battery device 10 can not only serve as a power source for the operation of the vehicle 100, but also serve as a driving power source for the vehicle 100, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 100.

[0089] Please refer to Figure 2 , Figure 2 An exploded view of the battery device 10 provided in some embodiments of the present application is shown. The battery device 10 can include a box 2 and a solid-state battery 1, the box 2 being configured to accommodate the solid-state battery 1.

[0090] The box 2 has an enclosed space formed inside for accommodating the solid-state battery 1. The box 2 can have various structures. In some embodiments, the box 2 can include a first box 21 and a second box 22, the first box 21 and the second box 22 being coupled to each other. The first box 21 and the second box 22 can have various shapes, such as a cuboid, a cylinder, etc. The first box 21 can be a hollow structure with one side open, and the second box 22 can also be a hollow structure with one side open. The open side of the second box 22 is coupled to the open side of the first box 21, thereby forming the box 2 with the enclosed space. Alternatively, the first box 21 can be a hollow structure with one side open, and the second box 22 can be a plate-shaped structure, the second box 22 being coupled to the open side of the first box 21, thereby forming the box 2 with the enclosed space.

[0091] In the battery device 10, the solid-state battery 1 can be one or a plurality of solid-state batteries 1. If the solid-state battery 1 is a plurality of solid-state batteries 1, the plurality of solid-state batteries 1 can be connected in series, in parallel, or in a mixed connection. The mixed connection means that the plurality of solid-state batteries 1 are connected in series and in parallel. The plurality of solid-state batteries 1 can be connected in series, in parallel, or in a mixed connection to form a battery module, and the plurality of battery modules can be connected in series, in parallel, or in a mixed connection to form a whole, which is accommodated in the box 2. Alternatively, all the solid-state batteries 1 can be directly connected in series, in parallel, or in a mixed connection, and the whole formed by the solid-state batteries 1 is accommodated in the box 2.

[0092] Please refer to Figure 3 , Figure 3 An exploded view of the solid-state battery 1 provided in some embodiments of the present application is shown. The solid-state battery 1 can include an electrode assembly 11 and a housing 12, the electrode assembly 11 being accommodated in the housing 12.

[0093] In some embodiments, the outer shell 12 can include a shell body 121 having an opening and an end cap 122 closing the opening of the shell body 121. Here, closing means covering or closing, which can be sealing or non-sealing.

[0094] The shell body 121 is a hollow structure having an opening at one end or openings at opposite ends for accommodating the electrode assembly 11. The shell body 121 can be in various shapes, such as a cylindrical shape, a cuboid shape, etc. The shell body 121 can be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, etc. The electrode assembly 11 can be partially or entirely located in the shell body 121.

[0095] The end cap 122 cooperates with the shell body 121 to define a receiving space for accommodating the electrode assembly 11 and other components. The end cap 122 can be connected to the shell body 121 by welding, crimping, etc. to close the opening of the shell body 121. The end cap 122 can be in a shape matching that of the shell body 121, such as a rectangular plate shape matching a cuboid structure of the shell body 121, or a circular plate shape matching a cylindrical structure of the shell body 121. The end cap 122 can be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, etc. The end cap 122 and the shell body 121 can be made of the same material or different materials.

[0096] In embodiments where the shell body 121 has an opening at one end, one end cap 122 can be provided. In embodiments where the shell body 121 has openings at opposite ends, two end caps 122 can be provided, each closing an opening of the shell body 121, and the two end caps 122 cooperates with the shell body 121 to define the receiving space.

[0097] In some embodiments, the solid-state battery 1 can further include an electrode terminal 13 provided on the outer shell 12, the electrode terminal 13 being electrically connected to the tab of the electrode assembly 11 to input or output electric energy of the solid-state battery 1. The electrode terminal 13 can be provided on the shell body 121 of the outer shell 12 or on the end cap 122 of the outer shell 12. The electrode terminal 13 can be directly connected to the tab, such as by welding. The electrode terminal 13 can be indirectly connected to the tab, such as by a current collecting member. The current collecting member can be a metal conductor, such as copper, iron, aluminum, steel, aluminum alloy, etc.

[0098] Please refer to Figure 4 , Figure 4A structural schematic diagram of a battery device 10 is provided for some embodiments of the present application. The embodiments of the present application provide a battery device 10, which includes a box 2, a constant pressure mechanism 4, a plurality of solid-state batteries 1 and a plurality of expansion members 3. The plurality of solid-state batteries 1 are arranged along a first direction X, and the plurality of solid-state batteries 1 are accommodated in the box 2. The plurality of expansion members 3 are arranged along the first direction X, and at least one solid-state battery 1 is arranged between two adjacent expansion members 3. The expansion member 3 has an expansion cavity (not shown in the figure) for accommodating a fluid medium (not shown in the figure). The constant pressure mechanism 4 is connected to the expansion member 3, and the constant pressure mechanism 4 is configured to release the fluid medium in the expansion cavity when the internal pressure value of the expansion cavity reaches a threshold value, and stop releasing the fluid medium in the expansion cavity when the internal pressure value of the expansion cavity is lower than the threshold value.

[0099] The plurality of solid-state batteries 1 are accommodated in the box 2. The box 2 has a carrier for arranging the solid-state batteries 1. The carrier can support the solid-state batteries 1, and the solid-state batteries 1 can move relative to the carrier. Alternatively, the carrier can be connected to the solid-state batteries 1, and the solid-state batteries 1 can be relatively static with the carrier. For example, the carrier can be bonded to the solid-state batteries 1. The carrier can be a wall of the box 2, or a water-cooled plate for adjusting the temperature of the solid-state batteries 1, and the like.

[0100] The plurality of expansion members 3 and the plurality of solid-state batteries 1 are arranged along the first direction X. For example, only one solid-state battery 1 can be arranged between two adjacent expansion members 3. For example, the two sides of each solid-state battery 1 can be provided with an expansion member 3. Alternatively, only a part of the solid-state batteries 1 can be provided with an expansion member 3 on both sides. Alternatively, a plurality of solid-state batteries 1 can be arranged between two adjacent expansion members 3. For example, an insulating member, such as a buffer pad, can be arranged between two adjacent solid-state batteries 1 among the plurality of solid-state batteries 1 arranged between the two adjacent expansion members 3.

[0101] The expansion member 3 has an expansion cavity. Filling the expansion cavity with a fluid medium can increase the internal pressure of the expansion member 3, and can also increase the volume of the expansion member 3, so as to limit the solid-state battery 1. For example, the expansion member is a capsule having an expansion cavity and capable of expansion. The plurality of expansion cavities can be communicated, so that the internal pressure values of the plurality of expansion cavities are the same. For example, the expansion member 3 can abut the outer surface of the solid-state battery 1 along the first direction X. Alternatively, the expansion member 3 can be bonded to the outer surface of the solid-state battery 1 along the first direction X. The fluid medium can be in a gaseous or liquid state. For example, the fluid medium can be nitrogen. For another example, the fluid medium can be water. The fluid medium can be pre-packaged in the expansion cavity, or can be filled into the expansion cavity during use.

[0102] The constant pressure mechanism 4 is connected to the expansion member 3, so that the constant pressure mechanism 4 can release the fluid medium in the expansion cavity. The constant pressure mechanism 4 can be located in the box 2; for example, the box 2 has a first chamber 24 and a second chamber 25, the solid-state battery 1 and the expansion member 3 are accommodated in the first chamber 24, and the constant pressure mechanism 4 is accommodated in the second chamber 25. The first chamber 24 and the second chamber 25 can be independent of each other, or the first chamber 24 and the second chamber 25 can be connected. The constant pressure mechanism 4 can also be located outside the box 2; for example, the constant pressure mechanism 4 is separately placed from the box 2, and the constant pressure mechanism 4 is connected to the expansion member 3 in the box 2 through a pipeline. For another example, the constant pressure mechanism 4 is placed on the outer top wall of the box 2.

[0103] The constant pressure mechanism 4 can release the fluid medium in the expansion member 3, and by adjusting the amount of the fluid medium in the expansion cavity, the internal pressure value of the expansion cavity is not higher than the threshold value. After the solid-state battery 1 expands, the volume of the expansion member 3 is compressed, and the pressure value in the expansion cavity increases. The constant pressure mechanism can release the fluid medium when the pressure value in the expansion cavity reaches the threshold value, so as to reduce the volume of the expansion member 3, thereby relieving the extrusion force of the expansion member 3 on the solid-state battery 1. The constant pressure mechanism stops releasing the fluid medium in the expansion cavity when the internal pressure value of the expansion cavity is lower than the threshold value, so that the expansion cavity can maintain a certain volume, so that the expansion member 3 can support the solid-state battery 1 to limit the position of the solid-state battery 1.

[0104] The threshold value can be different according to different design requirements. It can be understood that, in the normal use process of the battery device 10, the internal pressure value of the expansion cavity is less than the threshold value. When the expansion member 3 is extruded by the solid-state battery 1 to make the internal pressure value rise to the threshold value, the constant pressure mechanism 4 releases the fluid medium in the expansion cavity.

[0105] In the embodiments of the present application, at least one solid-state battery 1 is arranged between two adjacent expansion members 3. On the one hand, the expansion member 3 can limit the position of the solid-state battery 1, so that the position of the solid-state battery 1 is more stable. On the other hand, since the expansion of the solid-state battery 1 increases the volume of the solid-state battery 1, the expansion of the solid-state battery 1 extrudes the expansion member 3 to increase the internal pressure of the solid-state battery 1. By arranging the constant pressure mechanism 4 connected to the expansion member 3, the constant pressure mechanism 4 can release the fluid medium in the expansion cavity when the internal pressure of the expansion cavity reaches the threshold value, and stop releasing the fluid medium in the expansion cavity when the internal pressure value of the expansion cavity is lower than the threshold value, so that the expansion member 3 can provide a relatively stable extrusion force to the solid-state battery 1, thereby reducing the risk that the extrusion force of the expansion member 3 on the solid-state battery 1 is too large to damage the solid-state battery 1, and improving the reliability of the battery device 10.

[0106] In some embodiments, please refer to Figure 5 , Figure 5An assembly view of the inflation member 3 and the constant pressure mechanism 4 is provided for some embodiments of the present application. The constant pressure mechanism 4 comprises a switch unit 41 connected to the inflation member 3, and the switch unit 41 is configured to open when the internal pressure value of the inflation chamber reaches a threshold value, and to close when the internal pressure value of the inflation chamber is below the threshold value.

[0107] One switch unit 41 can be connected to multiple inflation members 3, and the switch unit 41 can release the fluid medium in multiple inflation chambers; or one switch unit 41 can be connected to one inflation member 3, and the switch unit 41 releases the fluid medium in the inflation chamber of the single inflation member 3 when the pressure value in the single inflation member 3 reaches the threshold value.

[0108] The switch unit 41 can be a valve that opens by the fluid medium in the inflation chamber; for example, the switch unit 41 can be a relief valve, and the relief valve has a threshold value of the opening pressure, and the relief valve can automatically open when the internal pressure value of the inflation chamber reaches the threshold value, and automatically close when the internal pressure value of the inflation chamber is below the threshold value. The switch unit 41 can also be a valve that opens by external control; for example, the switch unit 41 is a solenoid valve, and the solenoid valve controls its opening or closing by receiving a signal about the internal pressure value of the inflation chamber.

[0109] In the present embodiment, the switch unit 41 opens when the internal pressure of the inflation chamber reaches the threshold value, and closes when the internal pressure value of the inflation chamber is below the threshold value, so that the control of the amount of the fluid medium in the inflation member 3 can be achieved by the switch unit 41, and the control difficulty of the internal pressure value of the inflation chamber is reduced.

[0110] In some embodiments, please refer to Figure 6 , Figure 6 An assembly view of the inflation member 3 and the constant pressure mechanism 4 is provided for some embodiments of the present application. The constant pressure mechanism 4 further comprises a detection unit 42 for detecting the internal pressure value of the inflation member 3, and the switch unit 41 responds to the detection unit 42 to open when the internal pressure value of the inflation member 3 reaches the threshold value, and to close when the internal pressure value of the inflation member 3 is below the threshold value.

[0111] The detection unit 42 can be directly connected to the inflation member 3; for example, the detection unit 42 has a detection end that extends into the inflation chamber to detect the pressure value of the inflation chamber. The detection unit 42 can also be indirectly connected to the inflation member 3; for example, the inflation member 3 is connected to a pipeline for the flow of the fluid medium, the switch unit 41 is arranged in the pipeline, the detection unit 42 has a detection end, the detection end of the detection unit 42 extends into the pipeline, and the detection unit 42 is located between the inflation member 3 and the switch unit 41 to detect the pressure value of the inflation chamber. The detection unit 42 can be a pressure detector, and the switch unit 41 can open when the pressure value detected by the pressure detector reaches the threshold value.

[0112] In the embodiment where the switch unit 41 is multiple, each switch unit 41 is responsive to the detection unit 42 to open when the pressure value measured by the detection unit 42 reaches a threshold value, and to close when the pressure value measured by the detection unit 42 is below the threshold value.

[0113] In the embodiment, the detection unit 42 can drive the switch unit 41 to open when the internal pressure value of the expansion member 3 reaches a threshold value, and to close when the internal pressure value of the expansion member 3 is below the threshold value, so as to maintain the internal pressure value of the expansion member 3 in a relatively stable range, reducing the risk of damage to the solid-state battery 1 due to excessive internal pressure. The switch unit 41 is convenient to operate by responding to the detection unit 42 to release the internal pressure of the expansion chamber, and reduces the difficulty of regulating the internal pressure of the expansion chamber.

[0114] In some embodiments, please refer to Figure 7 , Figure 7 The assembly drawing of the expansion member 3 and the constant pressure mechanism 4 provided in some embodiments of the present application is shown. The constant pressure mechanism 4 further comprises a flow supply assembly 43 connected to the plurality of expansion members 3, and the flow supply assembly 43 is configured to provide fluid medium into the expansion chamber.

[0115] The flow supply assembly 43 can be located inside the box 2 or outside the box 2. In the embodiment where the box 2 comprises the second compartment 25, the flow supply assembly 43 can be located inside the second compartment 25.

[0116] The flow supply assembly 43 is used to provide fluid medium into the expansion member 3. The flow supply assembly 43 can be connected to the switch unit 41 or not. The flow supply assembly 43 can comprise a liquid tank, a gas tank, a pump or a compressor.

[0117] In the embodiment, by supplying fluid into the expansion chamber through the flow supply assembly 43, the internal pressure of the expansion chamber can be increased, thereby improving the fixing effect of the expansion member 3 on the solid-state battery 1, and making the position of the solid-state battery 1 more stable.

[0118] In some embodiments, after the solid-state battery 1 is discharged, the volume of the solid-state battery 1 can be reduced to reduce the limiting effect of the expansion member 3 on the solid-state battery 1. The flow supply assembly 43 can charge fluid medium into the expansion chamber to increase the internal pressure of the expansion chamber and improve the limiting effect of the expansion member 3 on the solid-state battery 1.

[0119] In some embodiments, a minimum pressure value can be set for the expansion chamber, and when the internal pressure of the expansion chamber is below the minimum pressure value, the flow supply assembly 43 can be used to supply fluid to the expansion chamber to increase the pressure.

[0120] In some embodiments, please continue to refer to Figure 7The supply flow assembly 43 comprises a storage unit 431 and a pumping unit 432. The storage unit 431 is configured to store the fluid medium. The pumping unit 432 is connected between the storage unit 431 and the expansion member 3, and is configured to pump the fluid medium in the storage unit 431 into the expansion cavity.

[0121] The pumping unit 432 is connected between the storage unit 431 and the expansion member 3, and is configured to pump the fluid medium in the storage unit 431 into the expansion member 3. The pumping unit 432 can pump liquid medium or gas medium. The pumping unit 432 can be a centrifugal pump, a gear pump or a diaphragm pump.

[0122] In the embodiment, the fluid medium stored in the storage unit 431 is pumped into the expansion cavity by the pumping unit 432, and the difficulty of supplying the fluid medium to the expansion cavity by the supply flow assembly 43 is reduced.

[0123] In some embodiments, the storage unit 431 is configured to store the fluid medium discharged from the expansion cavity through the switching unit 41.

[0124] The fluid medium discharged from the expansion cavity is introduced into the storage unit 431, and the fluid medium in the storage unit 431 can be pumped into the expansion cavity by the pumping unit 432.

[0125] In the embodiment, the fluid medium in the expansion cavity can flow into the storage unit 431, and the fluid medium in the storage unit 431 can also flow into the expansion cavity. On the one hand, the fluid medium can be recycled, and the cost of using the fluid medium is reduced. On the other hand, the fluid medium in the expansion cavity can be circulated, and in the process of circulation, the fluid medium can carry away the heat of the solid-state battery 1, thereby reducing the risk of thermal runaway of the solid-state battery 1 and improving the reliability of the battery device 10.

[0126] In some embodiments, please refer to Figure 8 , Figure 8 A structural schematic diagram of a battery device 10 provided in some embodiments of the present application is shown. The constant pressure mechanism 4 further comprises an outflow pipeline 44 and an inflow pipeline 45. The outflow pipeline 44 is connected between the pumping unit 432 and the plurality of expansion members 3, and the switching unit 41 is arranged on the outflow pipeline 44. The inflow pipeline 45 is connected between the storage unit 431 and the plurality of expansion members 3.

[0127] The outflow pipeline 44 is connected between the storage unit 431 and the plurality of expansion members 3, and the plurality of expansion members 3 can be connected in series through the outflow pipeline 44 or connected in parallel through the outflow pipeline 44. The outflow pipeline 44 is opened or closed by the switching unit 41, so as to realize the discharge or pressure maintenance of the expansion member 3.

[0128] The inflow pipeline 45 is connected to the pumping unit 432 and the plurality of expansion members 3. The plurality of expansion members 3 can be connected in series through the inflow pipeline 45, or can be connected in parallel through the inflow pipeline 45. Exemplarily, the plurality of expansion members 3 are connected in parallel through the inflow pipeline 45 and the outflow pipeline 44.

[0129] The pumping unit 432 pumps the fluid medium in the storage unit 431 into the inflow pipeline 45, and is delivered by the inflow pipeline 45 into the plurality of expansion members 3.

[0130] In the embodiment, by arranging the outflow pipeline 44 and the inflow pipeline 45, a closed loop can be formed between the constant pressure mechanism 4 and the expansion member 3, so as to facilitate the exchange of fluid medium between the expansion member 3 and the constant pressure mechanism 4, thereby guiding the heat of the solid-state battery 1 out of the expansion cavity through the fluid medium, and facilitating the temperature control of the solid-state battery 1.

[0131] In some embodiments, the expansion member 3 has an outflow port 33 for communicating with the outflow pipeline 44 and an inflow port 32 for communicating with the inflow pipeline 45. The outflow port 33 and the inflow port 32 can be located on the same side of the solid-state battery 1 along the second direction Y, or can be located on opposite sides of the solid-state battery 1 along the second direction Y, which is perpendicular to the first direction X.

[0132] In some embodiments, in a projection plane perpendicular to the first direction X, the orthographic projection of the solid-state battery 1 is located within the orthographic projection of the expansion member 3.

[0133] In the projection plane perpendicular to the first direction X, the orthographic projection of the solid-state battery 1 can completely overlap the orthographic projection of the expansion member 3, or the orthographic projection of the solid-state battery 1 can be located within the orthographic projection of the expansion member 3 and be smaller than the orthographic projection of the expansion member 3.

[0134] In the embodiment, by arranging that, in the projection plane perpendicular to the first direction X, the orthographic projection of the solid-state battery 1 is located within the orthographic projection of the expansion member 3, on the one hand, the risk of the solid-state battery 1 contacting the expansion member 3 on both sides of the expansion member 3 along the first direction X can be reduced, and the reliability of the battery device 10 can be improved; on the other hand, the contact area of the expansion member 3 and the solid-state battery 1 can be increased, so that the stress on the surface of the solid-state battery 1 contacting the expansion member 3 is more uniform, and the risk of the solid-state battery 1 being damaged can be reduced.

[0135] In some embodiments, in the projection plane perpendicular to the first direction X, the orthographic projection of the expansion member 3 is larger than the orthographic projection of the solid-state battery 1.

[0136] In the projection plane perpendicular to the first direction X, at least a part of the orthographic projection of the expansion member 3 exceeds the orthographic projection of the solid-state battery 1, and the orthographic projection of the solid-state battery 1 is entirely located within the orthographic projection of the expansion member 3, so that the orthographic projection of the expansion member 3 is larger than the orthographic projection of the solid-state battery 1.

[0137] In the embodiment, by setting the orthographic projection of the expansion member 3 to be larger than the orthographic projection of the solid-state battery 1, the risk of the solid-state battery 1 contacting the two sides of the expansion member 3 along the first direction X can be further reduced, and the support of the solid-state battery 1 by the expansion member 3 is more stable.

[0138] In some embodiments, please refer to Figure 9 , Figure 9 A structural schematic diagram of the solid-state battery 1 provided for some embodiments of the present application is shown. The solid-state battery 1 includes a housing 12 and an electrode assembly 11, the electrode assembly 11 is accommodated in the housing 12, the electrode assembly 11 includes a solid-state electrolyte layer 111 and a plurality of electrode sheets 112, along the first direction X, at least part of the solid-state electrolyte layer 111 is arranged between two adjacent electrode sheets 112, the electrode sheet 112 includes an active material layer, and in the two adjacent electrode sheets 112, the two active material layers facing the solid-state electrolyte layer 111 between the two adjacent electrode sheets 112 have opposite polarities.

[0139] Along the first direction X, all of the solid-state electrolyte layer 111 can be arranged between two adjacent electrode sheets 112, or only part of the solid-state electrolyte layer 111 can be arranged between two adjacent electrode sheets 112. The electrode sheet 112 can be provided with an active material layer on both sides along the first direction X, and the active material layer is provided with a solid-state electrolyte layer 111 on the side away from the electrode sheet 112. The electrode assembly 11 can be a laminated structure, and the electrode sheet 112 and the solid-state electrolyte layer 111 are arranged in layers along the first direction X.

[0140] In the embodiment, when the electrode assembly 11 expands along the first direction X, the solid-state battery 1 presses the expansion member 3 along the first direction X, and the expansion member 3 discharges the fluid medium to reduce the pressing force of the solid-state battery 1 along the first direction X, thereby reducing the risk of damage to the electrode assembly 11 due to expansion along the first direction X and improving the reliability of the battery device 10.

[0141] In some embodiments, please continue to refer to Figure 9 . The plurality of electrode sheets 112 includes a positive electrode sheet 112 and a negative electrode sheet 112, and along the first direction X, the solid-state electrolyte layer 111 is arranged between the positive electrode sheet 112 and the negative electrode sheet 112.

[0142] The positive electrode sheet 112 includes a positive electrode current collector 1121 and a positive electrode active material layer 1122, and the positive electrode current collector 1121 and the positive electrode active material layer 1122 are arranged in layers along the first direction X, and the positive electrode active material layer 1122 is provided with a solid-state electrolyte layer 111 on the side away from the positive electrode current collector 1121.

[0143] The negative electrode tab 112 includes a negative current collector 1123 and a negative active material layer 1124, and the negative current collector 1123 and the negative active material layer 1124 are stacked along the first direction X. The negative active material layer 1124 is provided with a solid-state electrolyte layer 111 on a side facing away from the negative current collector 1123.

[0144] In this embodiment, the solid-state electrolyte layer 111, the positive electrode tab 112, and the negative electrode tab 112 are stacked along the first direction X. The electrode assembly 11 is prone to expansion along the first direction X. By releasing the fluid medium in the expansion cavity, the internal pressure of the solid-state battery 1 can be reduced, thereby reducing the risk of damage to the solid-state battery 1.

[0145] In some embodiments, please refer to Figure 10 , Figure 10 A structural schematic diagram of the electrode assembly 11 provided in some embodiments of the present application is shown. The electrode tab 112 further includes a current collector 1125, and the current collector 1125 is provided with an active material layer on each of the two opposite surfaces along the first direction X, and the polarities of the active material layers on the two opposite surfaces of the current collector 1125 are opposite.

[0146] Exemplarily, as shown in Figure 10 , a plurality of current collectors 1125 are arranged at intervals along the first direction X. The current collector 1125 has a first surface 11251 and a second surface 11252 arranged opposite along the first direction X. The first surface 11251 of the current collector 1125 between two current collectors 1125 in the plurality of current collectors 1125 is provided with a positive active material layer 1122, and the second surface 11252 is provided with a negative active material layer 1124. In the two current collectors 1125 at the end of the plurality of current collectors 1125, the first surface 11251 of one current collector 1125 is provided with a positive active material layer 1122, and the second surface 11252 of the other current collector 1125 is provided with a negative active material layer 1124. The two current collectors 1125 are respectively connected to two electrode terminals 13 to output or input the electrical energy of the solid-state battery 1.

[0147] In this embodiment, the electrode assembly 11 is prone to expansion along the first direction X. By releasing the fluid medium in the expansion cavity, the internal pressure of the solid-state battery 1 can be reduced, thereby reducing the risk of damage to the solid-state battery 1.

[0148] In some embodiments, please continue to refer to Figure 4 . The shell 12 has a first outer surface 123, which is the surface with the largest outer surface area of the shell 12, and the first outer surface 123 is perpendicular to the first direction X.

[0149] The first outer surface 123 is perpendicular to the first direction X, so that the first outer surface 123 can face the expansion piece 3, so that the first outer surface 123 can be in contact with the expansion piece 3. The direction of the first outer surface 123 is the stacking direction of the pole piece 112 and the solid-state electrolyte layer 111. The electrode assembly 11 is easy to collide in the first direction X to extrude the first outer surface 123 to expand outward.

[0150] In the embodiment, by arranging the first outer surface 123 perpendicular to the first direction X, the first outer surface 123 can face the expansion piece 3, so that the contact area between the expansion piece 3 and the solid-state battery 1 can be increased, the position of the expansion piece 3 and the solid-state battery 1 is more stable, and the pressure between the solid-state battery 1 and the expansion piece 3 can be reduced, and the risk of damage to the solid-state battery 1 or the expansion piece 3 can be reduced.

[0151] In some embodiments, please continue to refer to Figure 4 The box body 2 includes two limiting portions 23 arranged opposite to each other along the first direction X, and the plurality of expansion pieces 3 and the plurality of solid-state batteries 1 are located between the two limiting portions 23 along the first direction X.

[0152] The limiting portion 23 can be a box wall of the box body 2, or the limiting portion 23 can be a stopper arranged in the box body 2. The plurality of expansion pieces 3 and the plurality of solid-state batteries 1 can be alternately arranged between the two limiting portions 23. The expansion piece 3 is also arranged between the solid-state battery 1 located at the end of the plurality of solid-state batteries 1 along the first direction X and the limiting portion 23, and the solid-state battery 1 and the limiting portion 23 jointly clamp the expansion piece 3.

[0153] In the embodiment, by arranging the expansion piece 3 and the solid-state battery 1 between the two limiting portions 23, the position of the expansion piece 3 and the solid-state battery 1 in the box body 2 can be more stable, and the assembly of the expansion piece 3 and the solid-state battery 1 can be more convenient.

[0154] In some embodiments, please continue to refer to Figure 4 Along the first direction X, the two expansion pieces 3 located at the two ends of the plurality of solid-state batteries 1 abut against the two limiting portions 23 respectively.

[0155] As shown in Figure 4 Each solid-state battery 1 has an expansion piece 3 abutting against each side along the first direction X. The two expansion pieces 3 at the ends along the first direction X abut against the two limiting portions 23 respectively.

[0156] In the embodiment, by arranging the expansion piece 3 in contact with the limiting portion 23, the risk of damage to the solid-state battery 1 due to contact with the limiting portion 23 can be reduced, the expansion piece 3 can also buffer the solid-state battery 1, further reducing the risk of damage to the solid-state battery 1, and improving the reliability of the battery device 10.

[0157] In some embodiments, the threshold value is 0.5-5 MPa.

[0158] The threshold value can be a point value of any one of 0.5 MPa, 0.6 MPa, 0.7 MPa, 0.8 MPa, 0.9 MPa, 1 MPa, 1.2 MPa, 1.5 MPa, 1.8 MPa, 2 MPa, 2.2 MPa, 2.5 MPa, 2.8 MPa, 3 MPa, 3.2 MPa, 3.5 MPa, 3.8 MPa, 4 MPa, 4.2 MPa, 4.5 MPa, 4.8 MPa, 5 MPa or a point value between any two of them.

[0159] In this embodiment, when the threshold value is greater than or equal to 0.5 MPa, the expansion member 3 can provide stable support force to the solid-state battery 1, improving the structural stability of the solid-state battery 1 in the box 2; when the threshold value is less than or equal to 5 MPa, the expansion member 3 releases the fluid medium when the internal pressure reaches the threshold value, so as to reduce the internal pressure of the expansion member 3, thereby reducing the extrusion force of the expansion member 3 against the solid-state battery 1, reducing the internal pressure of the solid-state battery 1, reducing the risk of damage to the solid-state battery 1, and improving the reliability of the battery device 10; therefore, when the threshold value is 0.5-5 MPa, the support of the expansion member 3 to the solid-state battery 1 and the reduction of the internal pressure of the solid-state battery 1 can be considered, the structural stability of the solid-state battery 1 is improved, and the reliability of the battery device 10 is improved.

[0160] In some embodiments, the threshold value is 2 MPa.

[0161] The threshold value is 2 MPa, and when the internal pressure of any expansion cavity reaches 2 MPa, the constant pressure mechanism 4 can release the fluid medium in the expansion cavity.

[0162] In this embodiment, the expansion member 3 can release the fluid medium when the internal pressure of the expansion cavity reaches 2 MPa, so as to reduce the internal pressure of the expansion cavity, thereby reducing the extrusion force of the expansion member 3 to the solid-state battery 1, further reducing the internal pressure of the solid-state battery 1, reducing the risk of damage to the solid-state battery 1, and improving the reliability of the battery device 10.

[0163] The embodiments of the present application provide a power consumption device, which comprises the battery device 10 provided by any one of the above embodiments.

[0164] Please continue to refer to Figure 8The embodiment of the present application provides a battery device 10, which comprises a box 2, a constant pressure mechanism 4, a plurality of solid-state batteries 1 and a plurality of expansion pieces 3. The plurality of solid-state batteries 1 are arranged along a first direction X, and the plurality of solid-state batteries 1 are accommodated in the box 2. The plurality of expansion pieces 3 are arranged along the first direction X, one solid-state battery 1 is arranged between every two adjacent expansion pieces 3, the expansion piece 3 has an expansion cavity for accommodating a fluid medium. The constant pressure mechanism 4 is connected with the expansion piece 3, and the constant pressure mechanism 4 is configured to release the fluid medium in the expansion cavity when an internal pressure value of the expansion cavity reaches a threshold value. The constant pressure mechanism 4 comprises a switch unit 41, a detection unit 42 and a flow supply assembly 43. The switch unit 41 is connected with the expansion piece 3, and the switch unit 41 is configured to be opened when the internal pressure value of the expansion cavity reaches the threshold value, so as to release the fluid medium in the expansion cavity. The detection unit 42 is used for detecting the internal pressure value of the expansion piece 3, and the switch unit 41 is responsive to the detection unit 42, so as to be opened when the internal pressure value of the expansion piece 3 reaches the threshold value. The flow supply assembly 43 is connected with the plurality of expansion pieces 3, and the flow supply assembly 43 is configured to provide the fluid medium into the expansion cavity. The constant pressure mechanism 4 further comprises an outflow pipeline 44 and an inflow pipeline 45. The outflow pipeline 44 is connected with a storage unit 431 and the plurality of expansion pieces 3, and the switch unit 41 is arranged on the outflow pipeline 44. The inflow pipeline 45 is connected with the storage unit 431 and the plurality of expansion pieces 3.

[0165] In the embodiment, by arranging a solid-state battery 1 between each two adjacent expansion members 3, on the one hand, the expansion members 3 can limit the position of the solid-state battery 1, so that the position of the solid-state battery 1 is more stable; on the other hand, since the expansion of the solid-state battery 1 can increase the volume of the solid-state battery 1, the expansion of the solid-state battery 1 extrudes the expansion members 3, which causes the internal pressure of the solid-state battery 1 to increase, and by releasing the fluid medium when the internal pressure of the expansion cavity reaches a threshold value, the extrusion force between the solid-state battery 1 and the expansion members 3 is reduced, so that the internal pressure of the solid-state battery 1 can be relieved, thereby reducing the risk of damage to the solid-state battery 1 and improving the reliability of the battery device 10. By opening the switch unit 41 when the internal pressure of the expansion cavity reaches a threshold value, the expansion cavity can release the fluid medium more conveniently, so that the release of the fluid medium is more stable, and the difficulty of releasing the internal pressure of the expansion cavity is reduced. The detection unit 42 can drive the switch unit 41 to open when the internal pressure value of the expansion member 3 reaches a threshold value, thereby reducing the risk of damage caused by excessive internal pressure of the solid-state battery 1, and the switch unit 41 releases the internal pressure of the expansion cavity in response to the detection unit 42, which is convenient to operate and reduces the difficulty of regulating the internal pressure of the expansion cavity. By supplying fluid to the expansion cavity through the fluid supply assembly 43, the internal pressure of the expansion cavity can be increased, thereby improving the fixing effect of the expansion member 3 on the solid-state battery 1, so that the position of the solid-state battery 1 is more stable. By arranging the outflow pipeline 44 and the inflow pipeline 45, a closed loop can be formed between the constant pressure mechanism 4 and the expansion member 3, so that the fluid medium can be exchanged between the expansion member 3 and the constant pressure mechanism 4, which is conducive to temperature control of the solid-state battery 1.

[0166] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0167] The above embodiments are only used to illustrate the technical solutions of the present application and are not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A battery device, characterized by, The application relates to a battery pack, comprising: a box body; a plurality of solid-state batteries arranged along a first direction, the plurality of solid-state batteries being accommodated in the box body; a plurality of expansion members arranged along the first direction, at least one solid-state battery being arranged between two adjacent expansion members, the expansion member having an expansion cavity for accommodating a fluid medium; a constant pressure mechanism connected to the expansion member, the constant pressure mechanism being configured to release the fluid medium in the expansion cavity when an internal pressure value of the expansion cavity reaches a threshold value, and stop releasing the fluid medium in the expansion cavity when the internal pressure value of the expansion cavity is lower than the threshold value.

2. The battery device of claim 1, wherein The constant pressure mechanism comprises a switch unit connected to the expansion member, the switch unit being configured to open when the internal pressure value of the expansion cavity reaches the threshold value, and close when the internal pressure value of the expansion cavity is lower than the threshold value.

3. The battery device of claim 2, wherein The constant pressure mechanism further comprises a detection unit for detecting the internal pressure value of the expansion member, the switch unit being responsive to the detection unit to open when the internal pressure value of the expansion member reaches the threshold value, and close when the internal pressure value of the expansion member is lower than the threshold value.

4. The battery device of claim 2, wherein The constant pressure mechanism further comprises a flow supply assembly connected to the plurality of expansion members, the flow supply assembly being configured to supply the fluid medium into the expansion cavity.

5. The battery device of claim 4, wherein The flow supply assembly comprises: a storage unit for storing the fluid medium; a pumping unit connected between the storage unit and the expansion member, the pumping unit being configured to pump the fluid medium in the storage unit into the expansion cavity.

6. The battery device of claim 5, wherein The storage unit is used for storing the fluid medium released from the expansion cavity through the switch unit.

7. The battery device of claim 6, wherein The constant pressure mechanism further comprises: an outlet flow pipeline connected between the storage unit and the plurality of expansion members, the switch unit being arranged in the outlet flow pipeline; an inlet flow pipeline connected between the pumping unit and the plurality of expansion members.

8. The battery device of any one of claims 1-7, wherein, In a projection plane perpendicular to the first direction, a projection of the solid-state battery is located in a projection of the expansion member.

9. The battery device of claim 8, wherein, In the projection plane perpendicular to the first direction, the projection of the expansion member is larger than the projection of the solid-state battery.

10. The battery device of any one of claims 1-7, wherein, The solid-state battery comprises a shell and an electrode assembly accommodated in the shell, the electrode assembly comprising a solid-state electrolyte layer and a plurality of electrode sheets, at least part of the solid-state electrolyte layer being arranged between two adjacent electrode sheets along the first direction, the electrode sheet comprising an active material layer, and the two active material layers of the two adjacent electrode sheets facing the solid-state electrolyte layer therebetween having opposite polarities.

11. The battery device of claim 10, wherein, The plurality of electrode sheets comprise positive electrode sheets and negative electrode sheets, and the solid-state electrolyte layer is arranged between the positive electrode sheet and the negative electrode sheet along the first direction.

12. The battery device of claim 10, wherein, The electrode sheet further comprises a current collector, opposite surfaces of the current collector being provided with the active material layer along the first direction, and the active material layers on the opposite surfaces of the current collector having opposite polarities.

13. The battery device of claim 10, wherein, The shell has a first outer surface, which is a surface with a largest outer surface area of the shell, and the first outer surface is perpendicular to the first direction.

14. The battery device of any one of claims 1-7, wherein, The box includes two limiting portions oppositely arranged along the first direction, and along the first direction, the plurality of expansion members and the plurality of solid-state batteries are located between the two limiting portions.

15. The battery device of claim 14, wherein, Along the first direction, the two expansion members located at both ends of the plurality of solid-state batteries respectively abut against the two limiting portions.

16. The battery device of any one of claims 1-7, wherein, The threshold value is 0.5-5 MPa.

17. The battery device of claim 16, wherein, The threshold value is 2 MPa.

18. An electrical device, comprising: A battery device comprising any one of claims 1-17.

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