All-solid-state battery and preparation method thereof

Abstract

The embodiment of the invention provides an all-solid-state battery and a preparation method thereof. The all-solid-state battery comprises a plurality of stacked battery cell units, and a structural supporting piece with deformation resistance is arranged between any two adjacent battery cell units; wherein the size of the surface, in contact with the battery cell unit, of each structure supporting piece is the same as the size of the corresponding contact surface on the battery cell unit, and the all-solid-state battery is prepared and obtained through an isostatic pressing process. According to the all-solid-state battery, the structural supporting pieces are arranged between the battery cell units, so that a good anti-deformation effect is achieved in the process of preparing the battery through isostatic pressing, densification treatment can be achieved without additionally arranging binding pieces, and the effect of improving the preparation efficiency of the all-solid-state battery is achieved; and by arranging the structural supporting piece in the all-solid-state battery, the effect of improving the structural strength of the all-solid-state battery can also be achieved.

Description

Technical Field

[0001] This invention relates to the field of batteries, and more particularly to an all-solid-state battery and its preparation method. Background Technology

[0002] Solid-state batteries, as a next-generation energy storage technology solution, have become a strategic high ground in the global competition for power batteries and energy storage due to their outstanding advantages such as high energy density, safety, and long cycle life. However, in practical production applications, the problem of poor solid-solid interface contact in solid-state batteries has hindered their industrialization process.

[0003] Currently, isostatic pressing (OSP) is a mature material densification method that can effectively solve this technical problem. To prevent battery deformation during the OSP process, a restraint clamp is usually installed in the battery before pressurization and removed after pressurization.

[0004] However, in the mass production of batteries, the tightening and loosening of clamps is required for each battery, making the pressurized fabrication process cumbersome and severely impacting the fabrication efficiency of all-solid-state batteries, thus limiting their mass production. Therefore, there is an urgent need for a technology that can improve the efficiency of the isostatic pressing fabrication process for batteries. Summary of the Invention

[0005] This invention provides an all-solid-state battery and its preparation method, which aims to improve the efficiency of isostatically charged batteries.

[0006] In a first aspect, the present invention provides an all-solid-state battery, the all-solid-state battery comprising a plurality of stacked cell units, and a structural support member with anti-deformation capability is provided between any two adjacent cell units.

[0007] The dimensions of the surface of each structural support that contacts the cell unit are the same as the dimensions of the corresponding contact surface on the cell unit; the all-solid-state battery is prepared by isostatic pressing.

[0008] In one possible implementation, the structural support includes a rigid support layer;

[0009] The rigid support layer is made of at least one of steel, aluminum alloy, titanium alloy, carbon fiber composite material, ceramic, glass fiber composite board, aramid fiber composite material, polycarbonate, nylon board, and polyetheretherketone; the flexural modulus of the rigid support layer is 5 to 500 GPa.

[0010] In one possible implementation, the structural support further includes an insulating buffer layer disposed on at least one side surface of the rigid support layer;

[0011] The insulating buffer layer is made of at least one of silicone, polyurethane, fluororubber, polyimide, polypropylene, and polyethylene.

[0012] In one possible implementation, the thickness of the structural support member is 0.05 to 50 mm.

[0013] A second aspect of the present invention provides a method for preparing an all-solid-state battery according to the first aspect above, the method comprising:

[0014] The positive electrode, electrolyte sheet, and negative electrode are stacked to form multiple battery cell units;

[0015] The multiple battery cells are stacked, and a structural support with anti-deformation capability is provided between any two adjacent battery cells during the stacking process to obtain a battery intermediate; wherein, the size of the surface of each structural support that contacts the battery cell is the same as the size of the corresponding contact surface on the battery cell.

[0016] The battery intermediate is densified using an isostatic pressing process to obtain the all-solid-state battery.

[0017] In one possible implementation, the structural support includes a rigid support layer;

[0018] The rigid support layer is made of at least one of steel, aluminum alloy, titanium alloy, carbon fiber composite material, ceramic, glass fiber composite board, aramid fiber composite material, polycarbonate, nylon board, and polyetheretherketone; the flexural modulus of the rigid support layer is 5 to 500 GPa.

[0019] In one possible implementation, the structural support further includes an insulating buffer layer disposed on at least one side surface of the rigid support layer;

[0020] The insulating buffer layer is made of at least one of silicone, polyurethane, fluororubber, polyimide, polypropylene, and polyethylene.

[0021] In one possible implementation, the thickness of the structural support member is 0.05 to 50 mm.

[0022] In one possible implementation, the isostatic pressure of the isostatic pressing process is 50-800 MPa.

[0023] In one possible implementation, the isostatic pressing temperature of the isostatic pressing process is 25–250°C.

[0024] A fourth aspect of the present invention provides an electrical device, comprising an electrical device body and the solid-state battery described in the third aspect.

[0025] The present invention has at least the following beneficial effects:

[0026] The all-solid-state battery provided by this invention, fabricated using an isostatic pressing process, features a structural support member with deformation resistance between any two adjacent cells. The dimensions of the surface of this structural support member that contacts the cell unit are identical to the dimensions of the corresponding contact surface on the cell unit. This ensures uniform stress distribution and excellent deformation resistance throughout the battery during isostatic pressing, eliminating the need for additional restraints to achieve densification and improving the fabrication efficiency of the all-solid-state battery. Furthermore, the inclusion of a structural support member within the all-solid-state battery also enhances its structural strength. Attached Figure Description

[0027] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0028] Figure 1 This is a schematic diagram of the battery binding structure in the traditional isostatic pressing process;

[0029] Figure 2 This is one of the cross-sectional structural schematic diagrams of the all-solid-state battery provided in Embodiment 1 of the present invention;

[0030] Figure 3 This is a second schematic cross-sectional view of the all-solid-state battery provided in Embodiment 1 of the present invention;

[0031] Figure 4 A structural diagram of a structural support member provided in Embodiment 1 of the invention;

[0032] Figure 5 This is a schematic flowchart of a method for preparing an all-solid-state battery according to Embodiment 2 of the present invention.

[0033] Figure label:

[0034] 10-Cell unit; 101-Positive current collector; 102-Positive active layer; 103-Electrolyte sheet; 104-Negative current collector; 105-Negative active layer; 20-Structural support; 201-Rigid support layer; 202-Insulating buffer layer.

[0035] The accompanying drawings have illustrated specific embodiments of the invention, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the invention in any way, but rather to illustrate the concept of the invention to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0036] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with some aspects of the invention as detailed in the appended claims.

[0037] To facilitate understanding of the technical content of this solution, the background technology is described in detail below:

[0038] Solid-state batteries, as a next-generation energy storage technology solution, have become a strategic high ground in the global power battery and energy storage field due to their outstanding advantages such as high energy density (theoretically up to 500 Wh / kg), safety (eliminating the risk of liquid electrolyte leakage and combustion), and long cycle life. Compared with traditional liquid lithium batteries, solid-state batteries use solid electrolytes as lithium-ion transport media, which not only have stronger thermal stability but also perform better in a wide temperature range, providing an ideal power solution for cutting-edge fields such as new energy vehicles, low-altitude economy, and robotics.

[0039] The research and industrialization of all-solid-state batteries are accelerating globally, with companies across the domestic industry chain actively investing in this area. However, from laboratory breakthroughs to mass production, all-solid-state batteries still face multiple technological bottlenecks. Interface issues, cost control, and manufacturing processes are considered the three core challenges. Among these, the engineering difficulties arising from the fundamental scientific problem of solid-solid interface contact are particularly prominent, severely hindering the industrialization process of all-solid-state batteries.

[0040] Specifically, during the preparation or cycling of solid-state batteries, the solid-solid interface between the electrode active material and the solid electrolyte is prone to problems such as contact degradation, residual pores, and insufficient particle contact, resulting in low interfacial ion transport efficiency and high contact resistance, which seriously affects battery performance and lifespan.

[0041] Currently, to effectively address the industry challenge of poor solid-solid interface contact in solid-state batteries, isostatic pressing (OSP) has been proposed as a battery manufacturing process. OSP, a mature material densification method, is based on Pascal's principle, using a liquid or gaseous medium to uniformly transfer pressure in all directions, achieving uniform pressurization across the entire surface of the workpiece. Specifically, its application in solid-state battery manufacturing is mainly concentrated in the densification process after battery stacking. Unlike the unidirectional pressing methods used in traditional lithium batteries, such as rolling and uniaxial surface pressing, isostatic pressing achieves three-dimensional uniform pressurization, effectively eliminating internal voids in the battery, improving interface density, and enhancing component contact performance.

[0042] Figure 1This is a schematic diagram of the battery restraint structure in the traditional isostatic pressing process. In current practical applications of isostatic pressing technology, considering the different deformations at various locations during the pressing process of stacked solid-state batteries, directly applying isostatic pressing to the stacked batteries would cause battery bending. Therefore, the stacked batteries are typically secured with metal sheet restraint clamps (see reference). Figure 1 Then, isostatic pressing is performed, and after the pressure is applied, the binding fixture is removed to achieve the purpose of preparing a flat solid-state battery.

[0043] However, existing methods require the tightening and loosening of clamps for each battery during mass production, making the pressurized fabrication process cumbersome and severely impacting the efficiency of all-solid-state battery fabrication, thus limiting its mass production. Therefore, there is an urgent need for a technology that can improve the efficiency of the isostatic pressing fabrication process for batteries.

[0044] Based on the above background technology, Embodiment 1 of the present invention provides an all-solid-state battery, which includes multiple stacked cell units, and a structural support member with anti-deformation capability is provided between any two adjacent cell units.

[0045] The dimensions of the surface of each structural support that contacts the cell unit are the same as the dimensions of the corresponding contact surface on the cell unit; the all-solid-state battery is prepared by isostatic pressing.

[0046] According to the inventors' research, considering that the purpose of adding binding clamps to the outside of the battery during the traditional isostatic pressing process for preparing all-solid-state batteries is to prevent bending deformation caused by isostatic pressing, the inventors considered adding appropriately sized structural supports with good resistance to deformation directly between the cell units inside the battery. This not only achieves the same effect of preventing battery deformation caused by inconsistent deformation in different areas of the battery during isostatic pressing, but also eliminates the need for tightening and removing binding clamps, thus significantly improving the preparation efficiency of the all-solid-state battery and ensuring its large-scale production.

[0047] In addition, the inventors also considered that the introduction of this deformation-resistant structural support component into the all-solid-state battery can improve the structural strength of the all-solid-state battery, making it less prone to structural deformation or damage during transportation, assembly, or extreme conditions (such as vibration, impact, and extrusion), thereby reducing safety risks such as internal short circuits and thermal runaway, and improving the safety and reliability of the battery throughout its entire life cycle.

[0048] In the all-solid-state battery provided by this invention, the number of stacked cell units is not specifically limited in this application, but can be determined according to the target performance and economic benefits of the battery actually manufactured.

[0049] Furthermore, each cell unit is formed by stacking a positive electrode, an electrolyte sheet, and a negative electrode. The positive electrode includes a positive current collector and a positive active layer; the negative electrode includes a negative current collector and a negative active layer. It should be noted that this application does not impose specific limitations on the positive electrode, electrolyte sheet, and negative electrode in the cell unit. These can be determined based on the target performance and economic benefits of the actual battery being manufactured. For example, they can be the positive electrode, electrolyte sheet, and negative electrode commonly used in the field of all-solid-state batteries.

[0050] In one possible implementation, the positive electrode current collector is made of at least one of aluminum, nickel, stainless steel, iron, titanium, and carbon, and / or the shape of the positive electrode current collector is foil or mesh. In practical applications, a positive electrode tab is usually provided at one end of the positive electrode current collector in all-solid-state batteries.

[0051] In one possible implementation, the raw materials for the positive electrode active layer include positive electrode active material, electrolyte material, conductive agent, and binder.

[0052] Positive electrode active materials include LiCoO2, LiMnO2, LiNiO2, LiVO2, and LiNi x Co y Mn z O2 (x+y+z=1; 0≤x<1, 0≤y<1, 0≤z<1), LiNi x Co y Al z O2 (x+y+z=1; 0≤x<1, 0≤y<1, 0≤z<1), xLi2MnO3·(1-x)LiTMO2 (TM=Ni, Mn, Co, Al; 0<x<1), LiMn2O4, Li4Ti5O 12 Li(Ni) 0.5 Mn 1.5 )O4, LiFePO4, LiMnPO4, LiNiPO4, LiCoPO4, LiMn x Fe 1-x PO4 (0 < x < 1), high-entropy cathode LiNi x Mn y M z O2 (M includes at least three of Co, Ti, V, Cr, Fe, Zn, Mg, Ca, Ru, Sn, Sb, W, Al, Mo, Y, Nb, La, Ce, Eu or Er, x+y+z=1; 0≤x<1, 0≤y<1, 0≤z<1)

[0053] In one possible implementation, the raw materials for the electrolyte sheet include an electrolyte material and a binder, wherein the electrolyte material is at least one of an oxide solid electrolyte, a halide solid electrolyte, and a sulfide electrolyte.

[0054] Among them, oxide solid electrolytes include Li 1+x Al x Ti 2-x (PO4)3 (0.1≤x≤0.9), Li7La3Zr2O 12 Li 6.4 La3Zr 1.4 Ta 0.6 O 12 Li 0.33 La 0.557 At least one of TiO3 and LiPON; and / or, the halide solid electrolyte includes at least one of Li3InCl6, Li2ZrCl6, Li3YCl6, Li3ScCl6, and derivatives of the above compounds (Li3InCl6, Li2ZrCl6, Li3YCl6, Li3ScCl6); and / or, the sulfide solid electrolyte includes Li x MP y S z (M is one or more of Sn, Ge, and Si, 0 < x, 0 < y, 0 < z), Li 7-x-y PS 6-x-y Cl x X y At least one of the following: (X is at least one of the halogen elements F, Br and I, 0≤x, 0≤y), xLi2S·(100-x)P2S5 (70≤x≤80), yLiI·zLiBr·(100-yz)(xLi2S·(100-x)P2S5) (70≤x≤80, 0≤y≤30, 0≤z≤30).

[0055] In addition, the binder is one or more of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), nitrile rubber (NBR), styrene-butadiene latex (SBR), polyacrylic acid (PAA), polyisobutylene (PIB), carboxymethyl cellulose (CMC), and hydrogenated styrene-butadiene block copolymer (SEBS); the conductive agent is at least one of conductive carbon black, carbon nanotubes (CNT), carbon nanofibers (CNF), and vapor-grown carbon fibers (VGCF).

[0056] In one possible implementation, the negative electrode current collector is made of at least one of copper, stainless steel, nickel, and carbon; and / or the shape of the negative electrode current collector is foil or mesh. In practical applications, a negative electrode tab is usually provided at one end of the negative electrode current collector in all-solid-state batteries.

[0057] In one possible implementation, the raw materials for the negative electrode active layer include a negative electrode active material, an electrolyte material, a conductive agent, and a binder. The negative electrode active material includes at least one of the following: lithium titanate, metallic Li, In, Sn, Li alloys, In alloys, Sn alloys, graphite, hard carbon, soft carbon, mesophase carbon microspheres, highly oriented pyrolytic graphite, or Si-based active materials such as elemental Si, Si alloys, silicon oxide, or silicon-carbon.

[0058] In practical applications, the part in contact with the structural support can be either the positive or negative electrode of the battery cell. Figure 2 and Figure 3 All of these are schematic cross-sectional views of the all-solid-state battery provided in Embodiment 1 of the present invention, such as... Figure 2 and Figure 3 As shown, the all-solid-state battery includes multiple stacked cell units 10, and a structural support member 20 is provided between any two adjacent cell units. Furthermore, the dimensions of the surface of each structural support member that contacts the cell unit are the same as the dimensions of the corresponding contact surface on the cell unit. Each cell unit 10 includes a positive electrode, an electrolyte sheet 103, and a negative electrode. The positive electrode includes a positive current collector 101 and a positive active layer 102, and the negative electrode includes a negative current collector 104 and a negative active layer 105.

[0059] Specifically, such as Figure 2 As shown, the structure of a cell unit in an all-solid-state battery can be "negative electrode current collector 104 - negative electrode active layer 105 - electrolyte sheet 103 - positive electrode active layer 102 - positive electrode current collector 101 - positive electrode active layer 102 - electrolyte sheet 103 - negative electrode active layer 105 - negative electrode current collector 104". It can be seen that in... Figure 2 In the all-solid-state battery shown, the negative electrode of the cell unit is in contact with the structural support.

[0060] Or, such as Figure 3 As shown, the structure of a cell unit in an all-solid-state battery can be "positive electrode current collector 101 - positive electrode active layer 102 - electrolyte sheet 103 - negative electrode active layer 105 - negative electrode current collector 104 - negative electrode active layer 105 - electrolyte sheet 103 - positive electrode active layer 102 - positive electrode current collector 101". It can be seen that in... Figure 3 In the all-solid-state battery shown, the positive electrode of the cell unit is in contact with the structural support.

[0061] It should be noted that the structural support component in the all-solid-state battery provided by this invention should have deformation resistance. The purpose of deformation resistance is to ensure that the structural support component provides good rigid support when the battery is subjected to external or internal stress, thereby providing uniform and continuous support force to the battery cells. For example, it can be a deformation-resistant material made of metal, fiber-reinforced composite material, or engineering plastic.

[0062] In one possible implementation, the structural support includes a rigid support layer; wherein the material of the rigid support layer includes at least one of steel, aluminum alloy, titanium alloy, carbon fiber composite material, ceramic, glass fiber composite board, aramid fiber composite material, polycarbonate, nylon board, and polyetheretherketone (PEEK); wherein the flexural modulus of the material of the rigid support layer is 5 to 500 GPa.

[0063] Specifically, in the structural support components of this solution, the rigid support layer can be made of any one of the following materials: steel, aluminum alloy, titanium alloy, carbon fiber composite material, ceramic, glass fiber composite board, aramid fiber composite material, polycarbonate, nylon board, and PEEK. It can also be composed of any combination of the above materials. For example, it can be composed of two, three, or more materials. This embodiment of the invention does not specifically limit this.

[0064] It should be noted that, to ensure the effective rigid support function of the selected materials, this specification limits the flexural modulus of the selected materials to 5–500 GPa. For example, the flexural modulus of the rigid support layer material may be 5 GPa, 50 GPa, 100 GPa, 200 GPa, 300 GPa, 350 GPa, 400 GPa, 450 GPa, or 500 GPa, or any two of the aforementioned values ​​may be selected to form a new range, with the value taken within that new range. For example, the rigid support layer material may be steel with a 260 GPa rating, or a nylon sheet with a 88 GPa rating, etc.

[0065] It should be understood that the materials used in this implementation are all capable of resisting external pressure and maintaining minimal deformation during isostatic pressing, thus preventing the battery from bending during the process. Furthermore, they all possess heat resistance, ensuring structural stability during warm isostatic pressing. Moreover, the selected carbon fiber composite material is lightweight, maintaining sufficient resistance to deformation while ensuring a low battery weight.

[0066] Furthermore, it should be noted that in the all-solid-state battery provided by this invention, the dimensions of the surface of each structural support member that contacts the cell unit are the same as the dimensions of the corresponding contact surface on the cell unit. The surface dimensions include both the length and width of the surface. It should be understood that this design aims to ensure that the structural support member fully covers the cell unit; it also avoids the possibility of cracks in the battery cell due to uneven stress caused by excessively small dimensions, and avoids unnecessary waste of raw materials due to excessively large dimensions.

[0067] Furthermore, in one possible implementation, the structural support member further includes an insulating buffer layer disposed on at least one surface of the rigid support layer. The insulating buffer layer is made of at least one of silicone, polyurethane, fluororubber, polyimide, polypropylene, and polyethylene.

[0068] It should be understood that, according to the inventors' further research, the rigid support layer of some materials may have conductive properties, which could easily cause short circuits between battery cells. Therefore, it is considered that an insulating buffer layer can be provided on one or both sides of the rigid support layer to block the risk of conductivity. At the same time, by utilizing the flexible properties of the insulating buffer layer, the structural support can be better adapted to the microstructure of the battery cell surface, achieving a tight fit between the structural support and the battery cell, thereby uniformly distributing the applied pressure to the entire contact surface of the battery cell, further ensuring the consistency of pressure transmission and improving the densification effect. In addition, the compression and rebound properties of the insulating buffer layer provide buffer space for the volume expansion of the battery cell, further improving the safety characteristics of the battery. Therefore, it is proposed that the structural support also include an insulating buffer layer disposed on at least one surface of the rigid support layer.

[0069] Specifically, in the structural support component of this solution, the insulating buffer layer can be made of any one of the following substances: silicone, polyurethane, fluororubber, polyimide, polypropylene, and polyethylene. It can also be composed of any combination of the above substances. For example, it can be composed of two, three, or more substances. This embodiment of the invention does not specifically limit this.

[0070] As a specific example Figure 4 A structural diagram of a structural support member provided in Embodiment 1 of the invention is shown below. Figure 4 As shown, the structural support in this example includes a rigid support layer 201 and an insulating buffer layer 202 disposed on both sides of the rigid support layer 201.

[0071] In another possible implementation, the thickness of the structural support in the aforementioned all-solid-state battery is 0.05–50 mm.

[0072] It should be understood that in order to ensure the supporting function of the structural support while also considering the energy density of the all-solid-state battery, an appropriate thickness of the structural support needs to be selected. For example, the thickness of the structural support may be 0.05mm, 0.1mm, 1mm, 5mm, 10mm, 20mm, 30mm, 40mm, or 50mm, or any two of the aforementioned values ​​may be selected to form a new range, with the value taken within that new range.

[0073] The all-solid-state battery prepared by the isostatic pressing process provided in this embodiment has a structural support member with anti-deformation capability placed between any two adjacent cells. The dimensions of the surface of the structural support member in contact with the cell unit are the same as the dimensions of the corresponding contact surface on the cell unit. This ensures that the battery is subjected to uniform stress and has good anti-deformation effect during the isostatic pressing process. Densification can be achieved without the need for additional restraints, thereby improving the preparation efficiency of the all-solid-state battery. In addition, by placing a structural support member inside the all-solid-state battery, the structural strength of the all-solid-state battery can also be improved.

[0074] Furthermore, Figure 5 This is a schematic flowchart of a method for preparing an all-solid-state battery according to Embodiment 2 of the present invention, as shown below. Figure 5 As shown, the method includes:

[0075] S301. The positive electrode, electrolyte sheet and negative electrode are stacked to form multiple battery cell units.

[0076] In this step, the pre-prepared positive electrode, electrode sheet and negative electrode need to be stacked to form multiple battery cell units.

[0077] For specific stacking methods, please refer to the description in the previous embodiment (e.g.) Figure 2 as well as Figure 3 The cell unit 10 in this embodiment will not be described in detail here. Furthermore, the preparation of the positive electrode, electrolyte sheet, and negative electrode can employ general methods from the solid-state battery field, and this application does not impose specific limitations.

[0078] As a specific example, the positive electrode, electrolyte sheet, and negative electrode can be prepared in the following manner:

[0079] 1) Preparation of the positive electrode:

[0080] The raw material of the positive electrode active layer is dry-rolled into a film to obtain a positive electrode sheet. The positive electrode sheet is then combined with a positive electrode current collector and die-cut to obtain the positive electrode. Alternatively, the raw material of the positive electrode active layer is wet-coated onto the positive electrode current collector and then die-cut to obtain the positive electrode.

[0081] 2) Preparation of electrolyte sheets:

[0082] The electrolyte sheet is obtained by dry rolling the raw material of the electrolyte sheet; or by wet coating the raw material of the electrolyte sheet onto a polyethylene terephthalate (PET) film or foil. In practical applications, the electrolyte sheet prepared by wet coating needs to be transferred onto the negative electrode active layer or the positive electrode active layer.

[0083] 3) The raw material of the negative electrode active layer is dry-rolled into a film to obtain a negative electrode sheet. The negative electrode sheet is then combined with the negative electrode current collector and die-cut to obtain the negative electrode. Alternatively, the raw material of the negative electrode active layer is wet-coated onto the negative electrode current collector and then die-cut to obtain the negative electrode.

[0084] S302. Multiple battery cell units are stacked, and during the stacking process, a structural support with anti-deformation capability is set between any two adjacent battery cell units to obtain a battery intermediate.

[0085] The dimensions of the surface of each structural support that contacts the battery cell are the same as the dimensions of the corresponding contact surface on the battery cell.

[0086] In this step, during the cell stacking process, a structural support with the same size as the corresponding surface on the cell unit and resistance to deformation is set between two adjacent cell units to obtain a battery intermediate.

[0087] The structure of the battery intermediate can also be referenced. Figure 2 or Figure 3 The stacked structure in the middle.

[0088] It should be understood that in practical production applications, continuous assembly line operations for battery intermediates can be achieved by alternating stacking of "cells and structural support components". This method eliminates the need for tightening and loosening of clamping fixtures in traditional isostatic pressing-based battery manufacturing methods, and can significantly improve the isostatic pressing preparation efficiency of all-solid-state batteries in large-scale production scenarios.

[0089] In one possible implementation, the structural support includes a rigid support layer; wherein the material of the rigid support layer includes at least one of steel, aluminum alloy, titanium alloy, carbon fiber composite material, ceramic, glass fiber composite board, aramid fiber composite material, polycarbonate, nylon board, and polyetheretherketone (PEEK); wherein the flexural modulus of the material of the rigid support layer is 5 to 500 GPa.

[0090] Specifically, in the structural support components of this solution, the rigid support layer can be made of any one of the following materials: steel, aluminum alloy, titanium alloy, carbon fiber composite material, ceramic, glass fiber composite board, aramid fiber composite material, polycarbonate, nylon board, and PEEK. It can also be composed of any combination of the above materials. For example, it can be composed of two, three, or more materials. This embodiment of the invention does not specifically limit this.

[0091] It should be understood that the materials used in this implementation are all capable of resisting external pressure and maintaining minimal deformation during isostatic pressing, thus preventing the battery from bending during the process. Furthermore, they all possess heat resistance, ensuring structural stability during warm isostatic pressing. Moreover, the selected carbon fiber composite material is lightweight, maintaining sufficient resistance to deformation while ensuring a low battery weight.

[0092] In one possible implementation, the structural support further includes an insulating buffer layer disposed on at least one surface of the rigid support layer. The insulating buffer layer is made of at least one of silicone, polyurethane, fluororubber, polyimide, polypropylene, and polyethylene.

[0093] Specifically, in the structural support component of this solution, the insulating buffer layer can be made of any one of the following substances: silicone, polyurethane, fluororubber, polyimide, polypropylene, and polyethylene. It can also be composed of any combination of the above substances. For example, it can be composed of two, three, or more substances. This embodiment of the invention does not specifically limit this.

[0094] It should be understood that this implementation, by introducing an insulating buffer layer into the structural support, serves two purposes: firstly, it ensures the insulation performance of the structural support, preventing short circuits between battery cells; secondly, it achieves a tight fit between the structural support and the battery cells, thereby evenly distributing the applied pressure across the entire contact surface of the battery cells. This further ensures consistent pressure transmission and improves the densification effect. Additionally, it provides buffer space for the volume expansion of the battery cells, further enhancing the battery's safety characteristics.

[0095] In one possible implementation, the thickness of the structural support is 0.05–50 mm.

[0096] It should be understood that in order to ensure the supporting function of the structural support while also considering the energy density of the all-solid-state battery, an appropriate thickness of the structural support needs to be selected. For example, the thickness of the structural support may be 0.05mm, 0.1mm, 1mm, 5mm, 10mm, 20mm, 30mm, 40mm, or 50mm, or any two of the aforementioned values ​​may be selected to form a new range, with the value taken within that new range.

[0097] It should be understood that the thickness of the structural support provided by this implementation method is sufficient to ensure the supporting function of the structural support while taking into account the energy density of the all-solid-state battery.

[0098] S303. The battery intermediate is densified using an isostatic pressing process to obtain an all-solid-state battery.

[0099] In this step, the aforementioned battery intermediate needs to be densified by isostatic pressing to obtain the all-solid-state battery.

[0100] As a specific example, positive and negative electrode tabs can be welded onto the battery intermediate, and after welding, the battery intermediate is vacuum-sealed with an aluminum-plastic film. The sealed battery intermediate is then densified under a preset isostatic pressure and isostatic temperature to obtain the all-solid-state battery.

[0101] In one possible implementation, the isostatic pressure of the isostatic pressing process is 50–800 MPa.

[0102] Specifically, the isostatic pressure for static pressure treatment is, for example, 50MPa, 100MPa, 200MPa, 300MPa, 400MPa, 500MPa, 600MPa, 700MPa, or 800MPa, or any two of the aforementioned values ​​can be selected to form a new range, and the values ​​taken within the new range can be used.

[0103] In one possible implementation, the isostatic pressing temperature is 25–250°C.

[0104] Specifically, the isostatic pressure temperature for static pressure treatment is, for example, 25℃, 50℃, 80℃, 100℃, 120℃, 160℃, 180℃, 200℃, 225℃, 250℃, or any two of the aforementioned values ​​can be selected to form a new range, and the values ​​taken within the new range can be used.

[0105] It should be understood that the temperature conditions provided by this implementation can both improve the interface density and avoid side reactions caused by high temperature.

[0106] The method for preparing an all-solid-state battery provided in this embodiment involves stacking a positive electrode, an electrolyte sheet, and a negative electrode to form multiple battery cells. These battery cells are then stacked, and during the stacking process, a structural support with deformation resistance is placed between any two adjacent battery cells to obtain a battery intermediate. The dimensions of the surface of each structural support that contacts the battery cell are the same as the dimensions of the corresponding contact surface on the battery cell. Finally, an isostatic pressing process is used to densify the battery intermediate, resulting in an all-solid-state battery. This method eliminates the need for clamping and removing the binding fixtures during the isostatic pressing process, effectively improving the battery preparation efficiency while ensuring that the battery does not deform during isostatic pressing.

[0107] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. An all-solid-state battery, characterized in that, The all-solid-state battery includes multiple stacked cell units, and a structural support with anti-deformation capability is provided between any two adjacent cell units. The dimensions of the surface of each structural support that contacts the cell unit are the same as the dimensions of the corresponding contact surface on the cell unit; the all-solid-state battery is prepared by isostatic pressing.

2. The all-solid-state battery according to claim 1, characterized in that, The structural support component includes a rigid support layer; The rigid support layer is made of at least one of steel, aluminum alloy, titanium alloy, carbon fiber composite material, ceramic, glass fiber composite board, aramid fiber composite material, polycarbonate, nylon board, and polyetheretherketone; the flexural modulus of the rigid support layer is 5 to 500 GPa.

3. The all-solid-state battery according to claim 2, characterized in that, The structural support also includes an insulating buffer layer disposed on at least one surface of the rigid support layer; The insulating buffer layer is made of at least one of silicone, polyurethane, fluororubber, polyimide, polypropylene, and polyethylene.

4. The all-solid-state battery according to any one of claims 1 to 3, characterized in that, The thickness of the structural support component is 0.05 to 50 mm.

5. A method for preparing an all-solid-state battery as described in any one of claims 1 to 4, characterized in that, The preparation method includes: The positive electrode, electrolyte sheet, and negative electrode are stacked to form multiple battery cell units; The multiple battery cells are stacked, and a structural support with anti-deformation capability is provided between any two adjacent battery cells during the stacking process to obtain a battery intermediate; wherein, the size of the surface of each structural support that contacts the battery cell is the same as the size of the corresponding contact surface on the battery cell. The battery intermediate is densified using an isostatic pressing process to obtain the all-solid-state battery.

6. The preparation method according to claim 5, characterized in that, The structural support component includes a rigid support layer; The rigid support layer is made of at least one of steel, aluminum alloy, titanium alloy, carbon fiber composite material, ceramic, glass fiber composite board, aramid fiber composite material, polycarbonate, nylon board, and polyetheretherketone; the flexural modulus of the rigid support layer is 5 to 500 GPa.

7. The preparation method according to claim 6, characterized in that, The structural support also includes an insulating buffer layer disposed on at least one surface of the rigid support layer; The insulating buffer layer is made of at least one of silicone, polyurethane, fluororubber, polyimide, polypropylene, and polyethylene.

8. The preparation method according to any one of claims 5 to 7, characterized in that, The thickness of the structural support component is 0.05 to 50 mm.

9. The preparation method according to any one of claims 5 to 7, characterized in that, The isostatic pressure of the isostatic pressing process is 50-800 MPa.

10. The preparation method according to any one of claims 5 to 7, characterized in that, The isostatic pressing temperature of the isostatic pressing process is 25-250℃.

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