Solution preparation method and application of inorganic binder for all-solid-state battery

Abstract

The invention discloses a solution preparation method and application of an inorganic binder for an all-solid-state battery. The solution type inorganic binder is composed of an inorganic solid electrolyte component and a polar organic solvent component, the inorganic solid electrolyte component accounts for 3%-20% of the total mass of the solution, and the room-temperature ionic conductivity of the inorganic solid electrolyte after the solvent is removed is 0.75 mS cm <-1 >. The solution type inorganic solid electrolyte binder is respectively mixed with positive electrode compound powder, inorganic solid electrolyte powder and negative electrode compound powder to form slurry, and an all-solid-state positive electrode membrane, an all-solid-state electrolyte membrane and an all-solid-state negative electrode membrane are respectively obtained in a wet blade coating mode. The soluble solid electrolyte can be used for bonding solid powder materials to form a compact all-inorganic solid membrane, and can also provide fast ion transport channels among particles. The preparation method is simple and easy to operate, can form a film in a large area, is suitable for large-scale batch production, and has an industrialization prospect.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical power sources, and in particular to a method for preparing a solution of an inorganic binder with high ion conductivity for an all-solid-state lithium secondary battery, and its application in various components of the all-solid-state battery. Background Art

[0002] Current commercial lithium-ion batteries use flammable and volatile organic liquid electrolytes as ion-conducting media, which inherently poses safety risks such as fire and explosion. Using non-flammable solid electrolytes to replace flammable organic electrolytes is expected to fundamentally improve the safety of lithium batteries. However, at present, large-area inorganic solid electrolyte membranes have difficulties in film processing, and the conductivity of the film-forming electrolyte layer is much lower than that of the bulk material. Therefore, how to develop large-area solid electrolyte ceramic membranes with high lithium ion conductivity and simple mechanical processing performance has become one of the hot topics in the current research of all-solid-state lithium batteries.

[0003] At present, there are two ways to prepare inorganic all-solid-state lithium secondary batteries: dry and wet. The dry process is to mix the solid electrolyte and PTFE binder and roll them into a film, but this electrolyte film is often thicker and has problems such as poor mechanical properties and unstable interfacial chemical properties. In the relevant literature (Hu et al., Inorganic glass electrolytes with polymer-like viscoelasticity [J]. Nature Energy, 8 (2023) 1221.), a class of high Li + and Na + Ionic conductivity (~1mS cm -1 ) is used as a solid electrolyte with a melting temperature below 160°C. It is used to prepare the ion conductive material of the positive electrode, but the dry film making technology is still used, which requires wire drawing, rolling, and high-temperature annealing. The process preparation is complicated and does not match the current lithium-ion battery preparation process equipment. The wet process mainly dissolves the organic polymer by solvent, and then mixes it with the inorganic solid electrolyte material powder to obtain an electrolyte membrane with an inorganic solid electrolyte as the main body by scraping. A sulfide composite electrolyte membrane and a preparation method thereof are disclosed in the patent document (CN202410026787.2), which mainly involves mixing different organic polymers as binders, sulfide solid electrolytes, and solvents, and drying the scraped sulfide electrolyte slurry to obtain a sulfide composite electrolyte membrane. Since this type of polymer accounts for a high proportion as a binder, it seriously affects the ion conductivity of the composite solid electrolyte and also reduces the energy density of the battery.

[0004] Here, the present invention provides a method for preparing an inorganic solid electrolyte solution with high ionic conductivity, which can be used for various components such as the positive electrode layer, electrolyte layer and negative electrode layer of an all-solid-state lithium battery, and is of great significance to promoting the development of all-solid-state lithium batteries. Summary of the invention

[0005] The purpose of the present invention is to overcome the problems of low ionic conductivity and difficult film processing technology in the existing all-solid-state battery film making technology, especially the electrolyte film making technology with inorganic solid electrolyte as the main body, and to provide a solution preparation method of an inorganic binder for all-solid-state batteries with reasonable formula, relatively low preparation difficulty and cost; another purpose of the present invention is to apply the solution-type inorganic binder of the present invention to the components of the positive electrode layer, electrolyte layer and negative electrode layer of an all-solid-state lithium battery and its all-solid-state lithium battery.

[0006] To achieve the above purpose, the present invention provides the following technical solutions: a method for preparing a solution of an inorganic binder for an all-solid-state battery and its application, wherein the solution-type inorganic binder is composed of an inorganic solid electrolyte component and a polar organic solvent component. The inorganic solid electrolyte component is an inorganic solid electrolyte with high ion conductivity, accounting for 3% to 20% of the total mass percentage of the solution; the polar organic solvent is one or more solvents.

[0007] A method for preparing a solution of an inorganic binder for an all-solid-state battery, characterized in that:

[0008] The process includes the following steps and process conditions:

[0009] Step 1: Preparation of polar organic solvent

[0010] Ultra-dry nitrogen methyl pyrrolidone (NMP) solvent is used as a single component and a main component, a certain amount (0% to 50%) of ultra-dry solvent is added according to a mass ratio, and a polar organic solvent is obtained after being stirred evenly for standby use.

[0011] Step 2: Preparation of inorganic solid electrolyte binder solution

[0012] The inorganic solid electrolyte is added into the polar organic solvent according to 3-20% of the total weight percentage of the solution to obtain the inorganic solid electrolyte binder solution.

[0013] Preferably, the ultra-dry solvent is one or more of N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO) and acetonitrile (AN).

[0014] Preferably, the solid electrolyte is lithium aluminum chloride (LiAlCl 2.5 O 0.75), lithium zirconium chloride (Li2ZrCl6), lithium yttrium chloride (Li3YCl6) and sodium aluminum chloride (NaAlCl 2.5 O 0.75 );

[0015] The present invention protects a solution-type inorganic solid electrolyte binder prepared by the above-mentioned preparation method, and application thereof in an all-solid-state lithium battery.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. The solution-type inorganic solid electrolyte binder of the present invention has multi-purpose functions. After removing the solvent, it can be used to bond solid powder materials to form a dense ceramic film, and can also provide a fast ion transport channel.

[0018] 2. The solution-type inorganic solid electrolyte binder of the present invention has a wide range of applications and can be mixed with positive electrode composite powder, inorganic solid electrolyte powder, and negative electrode composite powder to form corresponding slurries, and positive electrode ceramic membranes, electrolyte ceramic membranes, and negative electrode ceramic membranes can be obtained by wet scraping.

[0019] 3. The various ceramic membranes prepared by the present invention can reduce the interface impedance between the particles in the ceramic membrane and improve the room temperature ionic conductivity of the ceramic membrane because the solid electrolyte material can fill the pores between the crystal particles during the solvent removal process.

[0020] 4. The preparation method of the present invention is simple and easy to operate, and can form a large-area film, especially a ceramic film with a certain mechanical strength and adjustable thickness, which is suitable for large-scale batch production and has industrial prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 For the original LiAlCl 2.5 O 0.75 And LiAlCl after removing polar organic solvent 2.5 O 0.75 XRD comparison chart of materials;

[0022] Figure 2 LiAlCl after removal of polar organic solvent 2.5 O 0.75 Room temperature impedance test graph of the material and the room temperature ionic conductivity graph obtained by calculation;

[0023] Figure 3 LiAlCl 2.5 O 0.75 Dissolve and before and after photos comparison;

[0024] Figure 4 Composition: LiAlCl 2.5 O0.75 : NCM811: Super P = 20%: 75%: 5% solid positive electrode diagram;

[0025] Figure 5 Composition: LiAlCl 2.5 O 0.75 : Electron microscope image of solid electrolyte membrane of Li6PS5Cl=5%:95%;

[0026] Figure 6 All-solid-state lithium battery (Li-B|SSE|LiCoO2) at 60℃, 10mA g -1 Voltage-capacity diagram for charge and discharge under current density. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Example 1

[0029] The steps and process conditions of a method for preparing a solution of an inorganic binder for an all-solid-state battery are as follows:

[0030] Step 1: Preparation of polar organic solvent

[0031] Ultra-dry nitrogen methyl pyrrolidone (NMP) solvent is used as the main component, 1 wt.% of N,N-dimethylformamide (DMF) is added according to the mass ratio, and the polar organic solvent is obtained after stirring evenly, and is set aside.

[0032] Step 2: Preparation of inorganic solid electrolyte binder solution

[0033] The inorganic solid electrolyte LiAlCl 2.5 O 0.75 Add 20% of the total weight percentage of the solution into the polar organic solvent prepared in step 1 to obtain an inorganic solid electrolyte binder solution.

[0034] The solid electrolyte material obtained by removing the polar organic solvent from the inorganic solid electrolyte binder solution in this embodiment at 220°C was subjected to XRD test together with the initially synthesized solid electrolyte material. The experimental conclusions refer to the attached Figure 1 As shown. Figure 1 The XRD pattern shows that 20% LiAlCl 2.5 O 0.75The diffraction peaks after removing the solvent from the solution are similar to those of the initially synthesized LiAlCl 2.5 O 0.75 The diffraction peaks of the materials are consistent, and the broad peak near 20° is the peak of the polyimide isolation film that isolates the air. This result shows that polar organic solvents dissolve LiAlCl 2.5 O 0.75 The process has no obvious effect on LiAlCl 2.5 O 0.75 The crystal structure of the material is negatively affected.

[0035] The solid electrolyte material obtained by removing the polar organic solvent from the inorganic solid electrolyte binder solution in this embodiment at 220°C was pressed into tablets and then tested for room temperature ionic conductivity. The experimental conclusions refer to the attached Figure 2 As shown, the results show that the inorganic solid electrolyte LiAlCl 2.5 O 0.75 The room temperature ionic conductivity of the material can still reach 0.75 mS cm -1 .

[0036] Example 2

[0037] The steps and process conditions of a method for preparing a solution of an inorganic binder for an all-solid-state battery are as follows:

[0038] Step 1: Preparation of polar organic solvent

[0039] Ultra-dry nitrogen methyl pyrrolidone (NMP) solvent is used as the main component, 30% of N, N-dimethylformamide (DMF) is added according to the mass ratio, and after stirring evenly, a polar organic solvent is obtained for standby use.

[0040] Step 2: Preparation of inorganic solid electrolyte binder solution

[0041] The inorganic solid electrolyte LiAlCl 2.5 O 0.75 Add 10% of the total weight percentage of the solution into the polar organic solvent prepared in step 1 to obtain an inorganic solid electrolyte binder solution.

[0042] The experimental conclusions refer to the attached Figure 3 As shown, the bulk LiAlCl at the bottom during the dissolution of the inorganic solid electrolyte 2.5 O 0.75 The solid electrolyte gradually disappeared, accompanied by the solution color changing from white clear liquid to brown-yellow clear liquid.

[0043] Example 3

[0044] The steps and process conditions of a method for preparing a solution of an inorganic binder for an all-solid-state battery are as follows:

[0045] Step 1: Preparation of polar organic solvent

[0046] Ultra-dry nitrogen methyl pyrrolidone (NMP) solvent is used as the main component, 50% of N, N-dimethylformamide (DMF) is added according to the mass ratio, and after stirring evenly, a polar organic solvent is obtained for standby use.

[0047] Step 2: Preparation of inorganic solid electrolyte binder solution

[0048] Same as Example 2.

[0049] Step 3: Preparation of all-inorganic solid-state positive nickel-cobalt-manganese-oxide electrode film

[0050] The inorganic solid electrolyte binder solution is mixed with lithium nickel cobalt manganese oxide (NCM811) and a conductive agent (Super P) at a solid content mass ratio of 20%:75%:5%. After stirring for 5 hours, a positive electrode slurry is finally obtained. Then, the positive electrode slurry is coated on an aluminum foil current collector in an inert gas glove box. After heat treatment, an all-inorganic solid positive electrode layer is obtained.

[0051] The experimental conclusions refer to the attached Figure 4 As shown, the all-inorganic solid positive electrode layer can adhere very well to the surface of the aluminum foil current collector, and there is no phenomenon of powdering or falling off of the positive electrode layer.

[0052] Example 4

[0053] The steps and process conditions of a method for preparing a solution of an inorganic binder for an all-solid-state battery are as follows:

[0054] Step 1: Preparation of polar organic solvent

[0055] Same as Example 3

[0056] Step 2: Preparation of inorganic solid electrolyte binder solution

[0057] Same as Example 2

[0058] Step 3: Preparation of all-inorganic solid-state positive lithium manganese oxide electrode film

[0059] The inorganic solid electrolyte binder solution is mixed with lithium manganese oxide (Li2MnO4) and a conductive agent (VGCF) in a solid content mass ratio of 15%:80%:5%. After stirring for 5 hours, a positive electrode slurry is finally obtained. Then, the positive electrode slurry is coated on an aluminum foil current collector in an inert gas glove box. After heat treatment, an all-inorganic solid positive electrode layer is obtained.

[0060] The experimental results show that the all-inorganic solid positive electrode layer prepared in this embodiment can adhere to the surface of the aluminum foil current collector very well, and there is no phenomenon of powder loss and falling off of the positive electrode layer.

[0061] Example 5

[0062] The steps and process conditions of a method for preparing a solution of an inorganic binder for an all-solid-state battery are as follows:

[0063] Step 1: Preparation of polar organic solvent

[0064] Same as Example 3

[0065] Step 2: Preparation of inorganic solid electrolyte binder solution

[0066] Same as Example 2

[0067] Step 3: Preparation of all-inorganic solid-state positive electrode Li2S electrode film

[0068] The inorganic solid electrolyte binder solution is mixed with the sulfur-based positive electrode material (Li2S) and the conductive agent (VGCF) in a solid content mass ratio of 30%:65%:5%. After stirring for 5 hours, the positive electrode slurry is finally obtained. Then, the positive electrode slurry is coated on an aluminum foil current collector in an inert gas glove box. After heat treatment, an all-inorganic solid positive electrode layer is obtained.

[0069] The experimental results show that the all-inorganic solid positive electrode layer prepared in this embodiment can adhere to the surface of the aluminum foil current collector very well, and there is no phenomenon of powder loss and falling off of the positive electrode layer.

[0070] Example 6

[0071] The steps and process conditions of a method for preparing a solution of an inorganic binder for an all-solid-state battery are as follows:

[0072] Step 1: Preparation of polar organic solvent

[0073] Same as Example 3

[0074] Step 2: Preparation of inorganic solid electrolyte binder solution

[0075] Same as Example 2

[0076] Step 3: Preparation of sulfide-based all-inorganic solid electrolyte membrane

[0077] The inorganic solid electrolyte binder solution and the sulfide (Li6PS5Cl) solid electrolyte powder were mixed at a solid content mass ratio of 5%:95%, and the electrolyte slurry was finally obtained after stirring for 5 hours. Then, the electrolyte slurry was coated on the surface of carbon-coated aluminum foil in an inert gas glove box, and the sulfide-based all-inorganic solid electrolyte membrane was obtained after heat treatment.

[0078] The experimental conclusions refer to the attached Figure 5As shown in the figure, the electron scanning electron microscopy results show that the surface of the electrolyte layer is still relatively dense in microscopic morphology. The room temperature ionic conductivity of this all-inorganic solid electrolyte membrane is tested to be ~1mS cm -1 , indicating that a dense sulfide-based all-inorganic solid electrolyte membrane can be obtained by a simple scraping method.

[0079] Example 7

[0080] The steps and process conditions of a method for preparing a solution of an inorganic binder for an all-solid-state battery are as follows:

[0081] Step 1: Preparation of polar organic solvent

[0082] Same as Example 3

[0083] Step 2: Preparation of inorganic solid electrolyte binder solution

[0084] Same as Example 2

[0085] Step 3: Preparation of halide-based all-inorganic solid electrolyte membrane

[0086] The inorganic solid electrolyte binder solution and the halide (Li3InCl6) solid electrolyte powder are mixed at a solid content mass ratio of 5%:95%. After 5 hours of stirring, the electrolyte slurry is finally obtained. Then, the electrolyte slurry is coated on the surface of the polytetrafluoroethylene film in an inert gas glove box. After heat treatment to remove the solvent, the halide-based all-inorganic solid electrolyte membrane can still be obtained.

[0087] The experimental results show that a dense halide-based all-inorganic solid electrolyte membrane can be obtained by a simple scraping method.

[0088] Example 8

[0089] The steps and process conditions of a method for preparing a solution of an inorganic binder for an all-solid-state battery are as follows:

[0090] Step 1: Preparation of polar organic solvent

[0091] Same as Example 3

[0092] Step 2: Preparation of inorganic solid electrolyte binder solution

[0093] Same as Example 2

[0094] Step 3: Preparation of lanthanum zirconate lithium-based all-inorganic solid electrolyte membrane

[0095] The inorganic solid electrolyte binder solution is mixed with lanthanum zirconate lithium solid electrolyte powder (Li7La3Zr2O 12) are mixed at a solid content mass ratio of 2%:98%, and the electrolyte slurry is finally obtained after stirring for 5 hours. Then, the electrolyte slurry is coated on the surface of the polytetrafluoroethylene film in an inert gas glove box. After heat treatment to remove the solvent, a lanthanum zirconate lithium-based all-inorganic solid electrolyte layer can still be obtained.

[0096] The experimental results show that a dense lithium lanthanum zirconate-based all-inorganic solid electrolyte membrane can be obtained by a simple scraping method.

[0097] Example 9

[0098] The steps and process conditions of a method for preparing a solution of an inorganic binder for an all-solid-state battery are as follows:

[0099] Step 1: Preparation of polar organic solvent

[0100] Single component ultra-dry nitrogen methyl pyrrolidone (NMP) is used as the polar organic solvent.

[0101] Step 2: Preparation of inorganic solid electrolyte binder solution

[0102] The inorganic solid electrolyte Li2ZrCl6 is added into the polar organic solvent prepared in step 1 according to 10% of the total weight percentage of the solution to obtain an inorganic solid electrolyte binder solution.

[0103] Step 3: Preparation of lanthanum titanate lithium-based all-inorganic solid electrolyte membrane

[0104] The inorganic solid electrolyte binder solution is mixed with lanthanum titanate lithium solid electrolyte powder (Li 0.5 La 0.5 TiO3) is mixed at a solid content mass ratio of 20%:80%, and the electrolyte slurry is finally obtained after 5 hours of stirring. Then, the electrolyte slurry is coated on the surface of the polytetrafluoroethylene film in an inert gas glove box. After heat treatment to remove the solvent, the lanthanum titanate lithium-based all-inorganic solid electrolyte membrane can still be obtained.

[0105] The experimental results show that a dense lanthanum titanate lithium-based all-inorganic solid electrolyte membrane can be obtained by a simple scraping method.

[0106] Example 10

[0107] The steps and process conditions of a method for preparing a solution of an inorganic binder for an all-solid-state battery are as follows:

[0108] Step 1: Preparation of polar organic solvent

[0109] Same as Example 3.

[0110] Step 2: Preparation of inorganic solid electrolyte binder solution

[0111] The inorganic solid electrolyte Li3YCl6 is added to the polar organic solvent prepared in step 1 according to 10% of the total weight percentage of the solution to obtain an inorganic solid electrolyte binder solution.

[0112] Step 3: Lithium titanium aluminum phosphate-based all-inorganic solid electrolyte membrane

[0113] The inorganic solid electrolyte binder solution is mixed with lithium aluminum titanium phosphate solid electrolyte powder (Li 1.3 Al 0.3 Ti 1.7 (PO4)3) were mixed at a solid content mass ratio of 30%:70%, and the electrolyte slurry was finally obtained after stirring for 5 hours. The electrolyte slurry was then coated on the surface of the polytetrafluoroethylene film in an inert gas glove box. After heat treatment to remove the solvent, lithium titanium aluminum phosphate-based all-inorganic solid electrolyte membrane was still obtained.

[0114] The experimental results show that a dense lithium aluminum titanium phosphate-based all-inorganic solid electrolyte membrane can be obtained by a simple scraping method.

[0115] Embodiment 11

[0116] The steps and process conditions of a method for preparing a solution of an inorganic binder for an all-solid-state battery are as follows:

[0117] Step 1: Preparation of polar organic solvent

[0118] Ultra-dry nitrogen methyl pyrrolidone (NMP) solvent is used as the main component, 30% dimethyl sulfoxide (DMSO) is added according to the mass ratio, and after stirring evenly, a polar organic solvent is obtained for standby use.

[0119] Step 2: Preparation of inorganic solid electrolyte binder solution

[0120] The solid electrolyte NaAlCl 2.5 O 0.75 Add 10% of the total weight percentage of the solution into the polar organic solvent prepared in step 1 to obtain an inorganic solid electrolyte binder solution.

[0121] Step 3: Sodium zirconium silicon phosphorus all-inorganic solid electrolyte membrane

[0122] The inorganic solid electrolyte binder solution was mixed with sodium zirconium silicon phosphorus oxygen solid electrolyte powder (Na3Zr2Si2PO 12 ) are mixed in a solid content mass ratio of 10%:90%, and the electrolyte slurry is finally obtained after stirring for 5 hours. Then, the electrolyte slurry is coated on the surface of the polytetrafluoroethylene film in an inert gas glove box. After heat treatment to remove the solvent, a sodium zirconium silicon phosphorus all-inorganic solid electrolyte layer can still be obtained.

[0123] The experimental results show that a dense sodium zirconium silicon phosphorus oxide all-inorganic solid electrolyte membrane can be obtained by a simple scraping method.

[0124] Example 12

[0125] The steps and process conditions of a method for preparing a solution of an inorganic binder for an all-solid-state battery are as follows:

[0126] Step 1: Preparation of polar organic solvent

[0127] Same as Example 3

[0128] Step 2: Preparation of inorganic solid electrolyte binder solution

[0129] Same as Example 2

[0130] Step 3: All-inorganic solid-state negative electrode lithium titanate electrode film

[0131] The inorganic solid electrolyte binder solution is mixed with lithium titanate anode material (Li4Ti5O 12 ) are mixed at a solid content mass ratio of 10%:90%, and the electrolyte slurry is finally obtained after stirring for 5 hours. Then, the electrolyte slurry is coated on a copper foil current collector in an inert gas glove box. After heat treatment to remove the solvent, an all-inorganic solid-state negative electrode lithium titanate electrode film can still be obtained.

[0132] The experimental results show that the all-inorganic solid negative electrode layer prepared in this embodiment can adhere to the surface of the copper foil current collector very well, and there is no phenomenon of powdering and falling off of the negative electrode layer.

[0133] Embodiment 13

[0134] The steps and process conditions of a method for preparing a solution of an inorganic binder for an all-solid-state battery are as follows:

[0135] Step 1: Preparation of polar organic solvent

[0136] Ultra-dry nitrogen methyl pyrrolidone (NMP) solvent is used as the main component, 20% of N, N-dimethylformamide (DMF) and 10% of acetonitrile (AN) are added according to the mass ratio, and the polar organic solvent is obtained after stirring evenly, and then used for standby.

[0137] Step 2: Preparation of inorganic solid electrolyte binder solution

[0138] LiAlCl 2.5 O 0.75 The solid electrolyte is added into the polar organic solvent prepared in step 1 according to 3% of the total weight percentage of the solution to obtain an inorganic solid electrolyte binder solution.

[0139] Step 3: All-inorganic solid-state negative electrode silicon-based electrode membrane

[0140] The inorganic solid electrolyte binder solution and the silicon-based negative electrode material (Si / C) are mixed at a solid content mass ratio of 15%:85%. After stirring for 5 hours, the electrolyte slurry is finally obtained. Then, the electrolyte slurry is coated on the copper foil current collector in an inert gas glove box. After heat treatment to remove the solvent, an all-inorganic solid silicon-based negative electrode can still be obtained.

[0141] The experimental results show that the all-inorganic solid negative electrode layer prepared in this embodiment can adhere to the surface of the copper foil current collector very well, and there is no phenomenon of powdering and falling off of the negative electrode layer.

[0142] Embodiment 14

[0143] The steps and process conditions of a method for preparing a solution of an inorganic binder for an all-solid-state battery are as follows:

[0144] Step 1: Preparation of polar organic solvent

[0145] Same as Example 3

[0146] Step 2: Preparation of inorganic solid electrolyte binder solution

[0147] Same as Example 2

[0148] Step 3: Preparation of all-inorganic solid-state batteries

[0149] LiAlCl 2.5 O 0.75 , LiCoO2, and VGCF were prepared according to the solid content mass ratio of 20%:75%:5% to prepare the all-inorganic solid positive electrode LiCoO2 electrode layer; then, LiAlCl 2.5 O 0.75 、Li7La3Zr2O 12 A slurry with a solid content mass ratio of 5%:95% is coated on the LiCoO2 electrode layer; after removing the solvent, the iodide-treated lithium-boron (Li-B) alloy negative electrode is attached to the surface of the electrolyte layer to form an interface layer; finally, an all-inorganic solid-state lithium battery cell is obtained and assembled into button batteries for electrochemical performance testing.

[0150] Experimental conclusion reference Figure 6 As shown, the all-inorganic solid-state lithium battery prepared in this embodiment can be reversibly charged and discharged at 60°C.

[0151] Embodiment 15

[0152] The steps and process conditions of a method for preparing a solution of an inorganic binder for an all-solid-state battery are as follows:

[0153] Step 1: Preparation of polar organic solvent

[0154] Same as Example 3

[0155] Step 2: Preparation of inorganic solid electrolyte binder solution

[0156] Same as Example 2

[0157] Step 3: Preparation of all-inorganic solid-state batteries

[0158] LiAlCl 2.5 O 0.75 :NCM:Li3ZrCl6:VGCF prepared an all-inorganic solid positive electrode NCM electrode layer according to the solid content mass ratio of 5%:75%:15%:5%; then, LiAlCl 2.5 O 0.75 , Li6PS5Cl slurry is coated on the NCM electrode layer at a solid content mass ratio of 5%:95%; after removing the solvent, the metal lithium negative electrode containing the PEO interface layer is attached to the surface of the electrolyte layer, and a pressure of 2MPa is applied to make it fit tightly; finally, an all-inorganic solid-state lithium battery cell is obtained and assembled into button batteries for electrochemical performance testing.

[0159] The experimental results show that the all-inorganic solid-state lithium battery prepared in this embodiment can be reversibly charged and discharged at 60°C.

[0160] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0161] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A solution of an inorganic binder for an all-solid-state battery, Features: The solution-type inorganic binder is composed of an inorganic solid electrolyte component and a polar organic solvent component. The inorganic solid electrolyte component is an inorganic solid electrolyte with high ion conductivity, accounting for 3% to 20% of the total mass percentage of the solution; and the polar organic solvent is one or more solvents.

2. A method for preparing a solution of an inorganic binder for an all-solid-state battery, Features: The process includes the following steps and process conditions: Step 1: Preparation of polar organic solvent Ultra-dry nitrogen methyl pyrrolidone (NMP) solvent is used as a single component and a main component, a certain amount (0% to 50%) of ultra-dry solvent is added according to a mass ratio, and a polar organic solvent is obtained after being stirred evenly for standby use. Step 2: Preparation of inorganic solid electrolyte binder solution The inorganic solid electrolyte is added into the polar organic solvent according to 3-20% of the total weight percentage of the solution to obtain the inorganic solid electrolyte binder solution.

3. A method for preparing a solution of an inorganic binder for an all-solid-state battery according to claim 2, Features: The ultra-dry solvent is one or more of N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO) and acetonitrile (AN).

4. The method for preparing a solution of an inorganic binder for an all-solid-state battery according to claim 2, Features: The solid electrolyte is lithium aluminum chloride (LiAlCl 2.5 O 0.75 ), lithium zirconium chloride (Li 2 ZrCl 6 ), lithium yttrium chloride (Li 3 YC 6 ) and sodium aluminum chloride (NaAlCl 2.5 O 0.75 ).

5. A method for preparing a solution of an inorganic binder for an all-solid-state battery according to claims 2-4, Features: The prepared solution-type inorganic binder is used in the preparation of components of the positive electrode layer, electrolyte layer and negative electrode layer of an all-solid-state lithium battery and in the application of the all-solid-state lithium battery.

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