Negative electrode material, method for producing the same, and all-solid-state lithium battery

Abstract

This application provides a negative electrode material, a method for manufacturing the same, and an all-solid-state lithium battery. The negative electrode material includes a core and an amorphous lithium silicon alloy layer covering the core. The core includes a glassy solid electrolyte and amorphous lithium silicon alloy particles dispersed in the glassy solid electrolyte. The material of the amorphous lithium silicon alloy particles is Li x Si, where 0 < x ≤ 4.4, and the material of the amorphous lithium silicon alloy layer is Li y Si, where 0

Description

Technical Field

[0001] (Reference Application of Related Application) This application claims the priority of Chinese Patent Application No. 202110305372.5, titled "Negative Electrode Material and Its Manufacturing Method, and All-Solid-State Lithium Battery", filed with the China National Intellectual Property Administration on March 19, 2021, and all of its contents are incorporated herein by reference.

[0002] The present invention relates to the technical field of batteries, and specifically to a negative electrode material, its manufacturing method, and an all-solid-state lithium battery.

Background Art

[0003] In recent years, all-solid-state lithium batteries using solid electrolytes have attracted attention because of their high safety. Silicon negative electrodes with high theoretical specific capacity and high safety are considered an effective means to exceed the energy density of all-solid-state lithium batteries. However, conventional silicon negative electrode materials are prone to large volume changes during lithium desorption / insertion, which causes the capacity of all-solid-state lithium batteries to rapidly decay, the cycle performance to deteriorate, the contact between silicon negative electrode materials to be low, which is disadvantageous for reducing resistance, and the application of all-solid-state lithium batteries is limited.

Summary of the Invention

Problems to be Solved by the Invention

[0004] In view of this, the present application provides a negative electrode material, its manufacturing method, and an all-solid-state lithium battery. The contact between the negative electrode materials is high, the volume expansion effect of the negative electrode material is small during lithium desorption / insertion, the cycle stability is high, and the electrochemical performance is excellent. Therefore, the all-solid-state lithium battery manufactured using the negative electrode material has the advantages of high capacity and high cycle performance, which is advantageous for its application.

Means for Solving the Problems

[0005] According to the first aspect, the present application provides a negative electrode material, the negative electrode material includes a core and an amorphous lithium silicon alloy layer covering the core, the core includes a glassy solid electrolyte and amorphous lithium silicon alloy particles dispersed in the glassy solid electrolyte, and the material of the amorphous lithium silicon alloy particles is Li x Si, where 0 < x ≤ 4.4, and the material of the amorphous lithium silicon alloy layer is Li y Si, where 0 < y ≤ 4.4.

[0006] In some embodiments of the present application, the mass ratio of the amorphous lithium silicon alloy particles to the amorphous lithium silicon alloy layer is (1 to 100):1.

[0007] In some embodiments of the present application, in the core, the mass fraction of the amorphous lithium silicon alloy particles is 50% to 95%.

[0008] In some embodiments of the present application, the particle size of the amorphous lithium silicon alloy particles is 10 nm to 1 μm.

[0009] In some embodiments of the present application, the thickness of the amorphous lithium silicon alloy layer is 5 nm to 1 μm.

[0010] In some embodiments of the present application, the particle size of the negative electrode material is 20 nm to 20 μm.

[0011] In some embodiments of the present application, the glassy solid electrolyte includes at least one of a glassy oxide solid electrolyte and a glassy sulfide solid electrolyte.

[0012] In some embodiments of the present application, the glassy solid electrolyte includes, in mole percentage, 30 mol% to 80 mol% of Li2S, 10 mol% to 50 mol% of P2S5, 0 mol% to 30 mol% of SiS2, and 0 mol% to 30 mol% of LiA, where A is at least one of Cl, Br, and I.

[0013] In some embodiments of the present application, the glassy solid electrolyte contains, in mole percentage, 30 mol% to 80 mol% of Li2O, 10 mol% to 50 mol% of P2O5, 0 mol% to 30 mol% of SiS2, and 0 mol% to 30 mol% of LiA, where A is at least one of Cl, Br, and I.

[0014] In some embodiments of the present application, the glassy solid electrolyte contains, in mole percentage, 30 mol% to 80 mol% of Li2O, 20 mol% to 60 mol% of B2O3, and 0 mol% to 30 mol% of LiA, where A is at least one of Cl, Br, and I.

[0015] In some embodiments of the present application, the glassy solid electrolyte contains, in mole percentage, 30 mol% to 80 mol% of Li2S, 20 mol% to 60 mol% of SiS2, and 0 mol% to 30 mol% of LiA, where A is at least one of Cl, Br, and I.

[0016] In some embodiments of the present application, the glassy solid electrolyte contains, in mole percentage, 30 mol% to 85 mol% of Li2O, and 15 mol% to 70 mol% of LiA, where A is at least one of Cl, Br, and I.

[0017] In the negative electrode material according to the first aspect of the present application, since the outermost layer is an amorphous lithium silicon alloy layer, the contact performance between the negative electrode materials is improved, which is advantageous for reducing resistance. And the amorphous lithium silicon alloy particles are dispersed in the glassy solid electrolyte as a core, and the glassy solid electrolyte supports and disperses the amorphous lithium silicon alloy particles as the skeleton of the core, and buffers the volume expansion of the amorphous lithium silicon alloy particles, thereby reducing the volume expansion effect of the negative electrode material during the desorption / insertion of lithium. At the same time, the amorphous lithium silicon alloy layer fixes the core, ensures sufficient mixing and contact between the amorphous lithium silicon alloy particles and the glassy solid electrolyte, and the negative electrode materials all use an amorphous lithium silicon material and a glassy solid electrolyte having isotropy, which is advantageous for improving the transport efficiency of lithium ions and further improving the electrochemical performance of the negative electrode material.

[0018] According to a second aspect, the present application further provides a method for manufacturing a negative electrode material, the method comprising: Amorphous Li x A step of dispersing Si(0 < x ≤ 4.4) particles in a glassy solid electrolyte to obtain a core; Coating the core with amorphous Li y Si(0 < y ≤ 4.4) to obtain a negative electrode material.

[0019] In some embodiments of the present application, the step of coating the core with amorphous Li y Si includes the steps of ball-milling Li y Si to obtain the amorphous Li y Si, and mixing and ball-milling the core and the amorphous Li y Si to coat the core with the amorphous Li y Si.

[0020] The method for manufacturing a negative electrode material according to the second aspect of the present application can manufacture a negative electrode material with high contact property, small volume expansion effect during lithium desorption / insertion, high cycle stability, and excellent electrochemical performance. The process is simple, easy to operate, applicable to industrial production, and advantageous for the application of the negative electrode material.

[0021] According to a third aspect, the present application further provides an all-solid-state lithium battery including a positive electrode, a negative electrode, and a solid electrolyte layer located between the positive electrode and the negative electrode, wherein the negative electrode includes the negative electrode material described in the first aspect or the negative electrode material manufactured by the method described in the second aspect.

[0022] In some embodiments of the present application, the negative electrode includes a negative electrode current collector and a negative electrode material layer provided on the negative electrode current collector, and the negative electrode material layer includes the negative electrode material.

[0023] In some embodiments of the present application, the negative electrode material layer does not include a conductive agent.

[0024] The all-solid-state lithium battery according to the third aspect of the present application has high cycle performance, excellent electrochemical performance, and is advantageous for its application.

[0025] Additional aspects and advantages of the present disclosure will be shown in part in the following description, become apparent in part in the following description, or be understood by the practice of the present disclosure.

Brief Description of Drawings

[0026] The drawings described herein are for deepening the understanding of the present application, constitute a part of the present application, and the exemplary embodiments and their descriptions of the present application are for explaining the present application and do not limit the present application.

[0027]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0028] It should be noted that those skilled in the art can make several improvements and modifications without departing from the principle of the present application, and these improvements and modifications are also considered to be within the protection scope of the present application.

[0029] The following disclosure provides many different embodiments or examples to realize different structures of the present application. To simplify the disclosure of the present application, the members and installations of specific examples are described below. Naturally, these are only illustrative and not intended to limit the present application. In addition, the present application provides examples of various specific processes and materials, but those skilled in the art can be aware of the application of other processes and / or the use of other materials.

[0030] FIG. 1 is a schematic diagram of the structure of a negative electrode material according to an embodiment of the present application. The negative electrode material includes a core 11 and an amorphous lithium silicon alloy layer 12 covering the core 11. The core 11 includes a glassy solid electrolyte 111 and amorphous lithium silicon alloy particles 112 dispersed in the glassy solid electrolyte 111. The material of the amorphous lithium silicon alloy particles 112 is Li x Si, where 0 < x ≦ 4.4, and the material of the amorphous lithium silicon alloy layer 12 is Li y Si, where 0 < y ≦ 4.4.

[0031] In this application, all of the negative electrode materials 10 are amorphous and use an amorphous lithium silicon material and a glassy solid electrolyte having isotropy. Therefore, in the case of lithium ion desorption, since it is not affected by the insertion direction, it can desorb quickly, which is advantageous for lithium ion transport at the interface, improves the lithium ion transport speed and transport distance, improves the ionic conductivity, and also, compared with crystalline substances, the change in the internal structure of the amorphous substance under long-term charge-discharge conditions is small, the structure stability is excellent, and the service life is long. In the negative electrode material 10, the amorphous lithium silicon alloy particles 112 are dispersed in the glassy solid electrolyte 111 as the core 11, and the glassy solid electrolyte 111 supports and disperses the amorphous lithium silicon alloy particles 112 as the skeleton of the core 11, so that it is possible to effectively cope with the volume change of the amorphous lithium silicon alloy particles 112 during the cycling process, reduce the volume expansion effect of the negative electrode material 10 during lithium desorption / insertion, and guarantee the structure stability of the negative electrode material 10. Since the outer shell of the negative electrode material 10 is the amorphous lithium silicon alloy layer 12, when the negative electrode materials 10 come into contact with each other, there is no case where the contact failure or contact resistance is large due to the difference between the crystal phase and the crystal grain boundary, and it is more advantageous for the contact between the negative electrode materials 10, guaranteeing the reduction of the interface resistance. Therefore, the negative electrode material 10 according to this application has high charge-discharge performance, high cycle performance, and excellent electrochemical performance.

[0032] In this application, the glassy solid electrolyte 111 can effectively relieve the volume expansion effect of the amorphous lithium silicon alloy particles 112 and guarantee the long-term stable use of the negative electrode material 10.

[0033] In the embodiments of the present application, the mass fraction of the amorphous lithium silicon alloy particles 112 in the core 11 is 50% to 95%. Further, the mass fraction of the amorphous lithium silicon alloy particles 112 in the core 11 is 60% to 90%. Further, the mass fraction of the amorphous lithium silicon alloy particles 112 in the core 11 is 70% to 85%. Specifically, the mass fraction of the amorphous lithium silicon alloy particles 112 in the core 11 may be, but is not limited to, 55%, 57%, 60%, 65%, 72%, 75%, 78%, 80%, 83%, 86% or 90%. By providing the amorphous lithium silicon alloy particles 112 with the above content, the specific capacity of the negative electrode material 10 is guaranteed, which is advantageous for the application to all-solid-state lithium batteries.

[0034] In the present application, the shape of the amorphous lithium silicon alloy particles 112 is not limited. Specifically, it may be, but is not limited to, spherical, substantially spherical, etc. In the embodiments of the present application, the particle size of the amorphous lithium silicon alloy particles 112 is 10 nm to 1 μm. When the material is substantially spherical, the particle size is the equivalent particle size. Further, the particle size of the amorphous lithium silicon alloy particles 112 is 150 nm to 950 nm. Still further, the particle size of the amorphous lithium silicon alloy particles 112 is 230 nm to 870 nm. Specifically, the particle size of the amorphous lithium silicon alloy particles 112 may be, but is not limited to, 10 nm, 80 nm, 150 nm, 200 nm, 300 nm, 500 nm, 650 nm, 700 nm, 820 nm, 900 nm or 970 nm. By providing the amorphous lithium silicon alloy particles 112 with the above particle size, during the desorption / insertion of lithium, the volume expansion effect of the negative electrode material 10 can be alleviated, and the electrochemical activity of the desorption of lithium ions can be improved.

[0035] In the embodiment of the present application, the mass fraction of the glassy solid electrolyte 111 in the core 11 is 5% to 50%. Further, the mass fraction of the glassy solid electrolyte 111 in the core 11 is 10% to 40%. Further, the mass fraction of the glassy solid electrolyte 111 in the core 11 is 15 to 30%. Specifically, the mass fraction of the glassy solid electrolyte 111 in the core 11 may be, but is not limited to, 10%, 14%, 17%, 20%, 22%, 25%, 28%, 35%, 40%, 43% or 45%. By providing the glassy solid electrolyte 111 in the above content, the content of the amorphous lithium silicon alloy in the core 11 is guaranteed, which is advantageous for the insertion and desorption of lithium ions and improves the electrochemical performance of the negative electrode material 10.

[0036] In an embodiment of the present invention, the glassy solid electrolyte 111 includes at least one of a glassy oxide solid electrolyte and a glassy sulfide solid electrolyte. By providing the glassy solid electrolyte 111, it is advantageous for the transport of lithium ions. In one example, the glassy solid electrolyte 111 contains, in mole percentage, 30 mol% to 80 mol% of Li2S, 10 mol% to 50 mol% of P2S5, 0 mol% to 30 mol% of SiS2, and 0 mol% to 30 mol% of LiA, where A is at least one of Cl, Br, and I. Specifically, the glassy solid electrolyte 111 may contain, in mole percentage, 65 mol% of Li2S, 20 mol% of P2S5, 5 mol% of SiS2, and 10 mol% of LiA, but is not limited thereto. In another example, the glassy solid electrolyte 111 contains, in mole percentage, 30 mol% to 80 mol% of Li2O, 10 mol% to 50 mol% of P2O5, 0 mol% to 30 mol% of SiS2, and 0 mol% to 30 mol% of LiA, where A is at least one of Cl, Br, and I. Specifically, the glassy solid electrolyte 111 may contain, in mole percentage, 50 mol% of Li2O, 35 mol% of P2O5, 10 mol% of SiS2, and 5 mol% of LiA, but is not limited thereto. In another example, the glassy solid electrolyte 111 contains, in mole percentage, 30 mol% to 80 mol% of Li2O, 20 mol% to 60 mol% of B2O3, and 0 mol% to 30 mol% of LiA, where A is at least one of Cl, Br, and I. Specifically, the glassy solid electrolyte 111 may contain, in mole percentage, 70 mol% of Li2O, 25 mol% of B2O3, and 5 mol% of LiA, but is not limited thereto. In another example, the glassy solid electrolyte 111 contains, in mole percentage, 30 mol% to 80 mol% of Li2S, 20 mol% to 60 mol% of SiS2, and 0 mol% to 30 mol% of LiA, where A is at least one of Cl, Br, and I. Specifically, the glassy solid electrolyte 111 may contain, in mole percentage, 55 mol% of Li2S, 25 mol% of SiS2, and 20 mol% of LiA, but is not limited thereto.In another embodiment, the glassy solid electrolyte 111 contains, in mol percentage, 30 mol% to 85 mol% of Li2O and 15 mol% to 70 mol% of LiA, where A is at least one of Cl, Br, and I. Specifically, the glassy solid electrolyte 111 may contain, in mol percentage, 70 mol% of Li2O and 30 mol% of LiA, but is not limited thereto.

[0037] In the present application, by providing the amorphous lithium silicon alloy layer 12, the contact performance between the negative electrode materials 10 is improved, which is advantageous for reducing the resistance of the negative electrode materials 10. The material of the amorphous lithium silicon alloy particles 112 (Li x Si) and the material of the amorphous lithium silicon alloy layer 12 (Li y Si) may have the same or different values of x and y. In one embodiment of the present application, 2 < x ≤ 4.4 and 2 < y ≤ 4.4. Specifically, x and y are independently selected from 1.71, 2.33, 3.25, 3.75, or 4.4, etc.

[0038] In the embodiment of the present application, the thickness of the amorphous lithium silicon alloy layer 12 is 5 nm to 1 μm. Further, the thickness of the amorphous lithium silicon alloy layer 12 is 60 nm to 950 nm. Still further, the thickness of the amorphous lithium silicon alloy layer 12 is 150 nm to 820 nm. Specifically, the thickness of the amorphous lithium silicon alloy layer 12 may be 10 nm, 80 nm, 150 nm, 200 nm, 300 nm, 500 nm, 650 nm, 700 nm, 820 nm, 900 nm, 970 nm, etc., but is not limited thereto. By providing the amorphous lithium silicon alloy layer 12 with the above thickness, the thickness of the amorphous lithium silicon alloy layer 12 is relatively thin, and the amorphous lithium silicon alloy layer 12 mainly functions to fix and protect the core 11, and further improves the contact performance between the negative electrode materials 10.

[0039] In the embodiments of the present application, the ratio of the radius of the core 11 to the thickness of the amorphous lithium silicon alloy layer 12 is 2 to 9. Further, the ratio of the radius of the core 11 to the thickness of the amorphous lithium silicon alloy layer 12 is 3 to 8. Still further, the ratio of the radius of the core 11 to the thickness of the amorphous lithium silicon alloy layer 12 is 4 to 7.5. Specifically, the ratio of the radius of the core 11 to the thickness of the amorphous lithium silicon alloy layer 12 may be 2, 2.5, 4, 4.5, 5, 5.8, 6, 6.5, 7, 7.2, 8.5, etc., but is not limited thereto. Thereby, it is advantageous to improve the content of the core 11, strengthen the transport of lithium ions, and improve the specific capacity of the negative electrode material 10.

[0040] In the embodiments of the present application, the mass ratio of the amorphous lithium silicon alloy particles 112 to the amorphous lithium silicon alloy layer 12 is (1 to 100):1. Further, the mass ratio of the amorphous lithium silicon alloy particles 112 to the amorphous lithium silicon alloy layer 12 is (10 to 95):1. Still further, the mass ratio of the amorphous lithium silicon alloy particles 112 to the amorphous lithium silicon alloy layer 12 is (20 to 80):1, (25 to 80):1, (30 to 70):1, (25 to 70):1, or (30 to 65):1, etc. Specifically, the mass ratio of the amorphous lithium silicon alloy particles 112 to the amorphous lithium silicon alloy layer 12 may be 15:1, 20:1, 25:1, 30:1, 40:1, 45:1, 50:1, 55:1, 60:1, 70:1, 80:1, 90:1, 95:1, etc., but is not limited thereto. Thereby, the amorphous lithium silicon alloy particles 112 mainly function to insert and desorb lithium ions, and the amorphous lithium silicon alloy layer 12 functions to protect and fix the core 11, which is advantageous for improving the lithium ion transport effect.

[0041] In the embodiments of the present application, the particle size of the negative electrode material 10 is 20 nm to 20 μm. Further, the particle size of the negative electrode material 10 is 100 nm to 19 μm. Still further, the particle size of the negative electrode material 10 is 0.5 μm to 18 μm, 1 μm to 17 μm, 2 μm to 16 μm, 3 μm to 15 μm, 5 μm to 13 μm, or 7 μm to 12 μm, etc. Specifically, the particle size of the negative electrode material 10 may be 50 nm, 1.5 μm, 2.8 μm, 4.5 μm, 8 μm, 10 μm, 12.5 μm, 14 μm, 16 μm, 18 μm, etc., but is not limited thereto.

[0042] In the embodiments of the present application, the ionic conductivity of the negative electrode material 10 at room temperature is 10 -7 S·cm -1 or more, and the room temperature is 15°C to 30°C.

[0043] In the embodiments of the present application, the electronic conductivity of the negative electrode material 10 at room temperature is 10 -2 S·cm -1 or more, and the room temperature is 15°C to 30°C.

[0044] FIG. 2 is a flowchart of a method for manufacturing a negative electrode material according to an embodiment of the present application. The method includes Step S101 of dispersing amorphous Li x Si (0 < x ≤ 4.4) particles in a glassy solid electrolyte to obtain a core, and Step S102 of coating the core with amorphous Li y Si (0 < y ≤ 4.4) to obtain a negative electrode material.

[0045] In the present application, an amorphous raw material may be directly provided and mixed, or an amorphous raw material may be obtained by ball milling. In an embodiment of the present application, the step of dispersing amorphous Li x Si particles in a glassy solid electrolyte includes the step of uniformly mixing the amorphous Li x Si particles with the glassy solid electrolyte. In another embodiment of the present application, the step of dispersing amorphous Li x Si particles in a glassy solid electrolyte is Li xMix Si particles with a solid electrolyte, and after ball milling and mixing, amorphous Li x Si particles are dispersed in a glassy solid electrolyte to obtain amorphous Li x Si particles and a glassy solid electrolyte. Further, the rotation speed of the ball milling and mixing is 150 rpm to 350 rpm, and the processing time is 1 h to 5 h. Still further, the rotation speed of the ball milling and mixing is 200 rpm to 300 rpm, and the processing time is 2 h to 4 h. Amorphous raw materials can be obtained by long-time high-rotation-speed ball milling, and the contact performance between the glassy solid electrolytes and between the glassy solid electrolyte and amorphous Li x Si is high, which is advantageous for reducing resistance and improving ion conductivity. In yet another embodiment of the present application, the step of dispersing amorphous Li x Si particles in a glassy solid electrolyte further includes a step of performing heat treatment. The heat treatment improves the interfacial compatibility between the amorphous Li x Si particles and the glassy solid electrolyte, and further improves the contact performance. In one example, the heat treatment includes heating to 250°C to 400°C at a rate exceeding 10°C / min and holding for 10 min to 60 min. Specifically, it may be heating to 300°C at a rate exceeding 10°C / min and holding for 30 min, but is not limited thereto.

[0046] In an embodiment of the present application, the step of coating the core 11 with amorphous Li y Si includes ball milling Li y Si to obtain amorphous Li y Si, and then mixing the core 11 and amorphous Li y Si and performing ball milling, and then amorphous Li yIt includes the step of coating the core 11 with Si. In one embodiment of the present application, the ball milling method may be wet ball milling or dry ball milling. Specifically, the solvent in wet ball milling includes, but is not limited to, at least one of toluene, xylene, anisole, heptane, decane, ethyl acetate, ethyl propionate, butyl butyrate, N-methylpyrrolidone, acetone, etc. In another embodiment of the present application, the rotation speed of ball milling is 50 rpm to 250 rpm, and the time is 5 min to 30 min. Further, the rotation speed of ball milling is 150 rpm to 250 rpm, and the time is 20 min to 30 min.

[0047] In an embodiment of the present application, the production of the negative electrode material 10 is carried out in an atmosphere of a protective gas. Specifically, the protective gas includes at least one of nitrogen gas, helium, hydrogen gas, etc.

[0048] The related parameters and functions of the negative electrode material 10 produced by the production method of the present application are as described above, and the description is omitted here.

[0049] The production method of the negative electrode material 10 according to the present application can produce a negative electrode material with high contact property, low volume expansion effect during lithium desorption / insertion, high cycle stability, and excellent electrochemical performance. The process is simple, easy to operate, applicable to industrial production, and advantageous for the application of the negative electrode material.

[0050] As shown in Figure 3, it is a schematic structural diagram of an all-solid-state lithium battery according to an embodiment of the present application. The all-solid-state lithium battery includes a positive electrode 200, a negative electrode 100, and a solid electrolyte layer 300 located between the positive electrode 200 and the negative electrode 100. The negative electrode 100 includes the negative electrode material 10 in any of the above embodiments.

[0051] In an embodiment of the present application, the negative electrode 100 includes a negative electrode current collector 102 and a negative electrode material layer 101 provided on the negative electrode current collector 102, and the negative electrode material layer 101 includes a negative electrode material 10. Specifically, the thickness of the negative electrode material layer 101 may be 5 μm to 50 μm, but is not limited thereto.

[0052] In an embodiment of the present application, the negative electrode material layer 101 does not contain a conductive agent. In this way, the negative electrode material layer 101 may include many negative electrode materials 10 having electrochemical activity, whereby the capacity of the negative electrode 100 increases and the energy density of the all-solid-state lithium battery increases.

[0053] In an embodiment of the present application, the negative electrode material layer 101 further includes at least one of binders. The binder contributes to firmly fixing the negative electrode material layer 101 to the negative electrode current collector 102 and gives the negative electrode material layer 101 a certain elasticity. In an example of the present application, the binder may include at least one of polythiophene, polypyrrole, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polystyrene, polyacrylamide, ethylene-propylene-diene copolymer resin, styrene-butadiene rubber, polybutadiene, fluororubber, polyvinylpyrrolidone, polyester resin, acrylic resin, phenol resin, epoxy resin, polyvinyl alcohol, carboxypropyl cellulose, ethyl cellulose, polyethylene oxide, sodium carboxymethyl cellulose, and styrene-butadiene rubber, but is not limited thereto. In another example of the present application, the mass percentage of the binder in the negative electrode material layer 101 is 0.5% to 5%. Specifically, the mass percentage of the binder in the negative electrode material layer 101 may be 1% to 5%, 1.5% to 4.5%, 2% to 4%, or 2.5% to 3.8%, etc., but is not limited thereto.

[0054] In an embodiment of the present application, the positive electrode 200 may include a positive electrode current collector 202 and a positive electrode material layer 201 provided on the positive electrode current collector 202. The positive electrode material layer 201 may include a positive electrode active material, a conductive agent, a solid electrolyte material for the positive electrode, and a binder for the positive electrode.

[0055] In an embodiment of the present invention, the positive electrode active material includes any one or more of an oxide-based material, a sulfide-based material, a polyanion-based material, and a composite of each of the above materials. In one example of the present invention, the oxide-based positive electrode active material includes TiO2, Cr3O8, V2O5, MnO2, NiO, WO3, LiMn2O4, Li2CuO2, LiCo m Ni 1-m O2 (0 ≦ m ≦ 1), LiCo a Ni 1-a-b Al b O2 (0 ≦ a ≦ 1, 0 ≦ b ≦ 1), LiFe c Mn d G e O4 (G is at least one selected from the group consisting of Al, Mg, Ga, Cr, Co, Ni, Cu, Zn, and Mo, 0 ≦ c ≦ 1, 0 ≦ d ≦ 1, 0 ≦ e ≦ 1, c + d + e = 1), Li 1+f L 1-g-h H g R h O2 (L, H, and R are each independently at least one selected from the group consisting of Li, Co, Mn, Ni, Fe, Al, Mg, Ga, Ti, Cr, Cu, Zn, Mo, F, I, S, and B, and L, H, and R are different elements from each other, and -0.1 ≦ f ≦ 0.2, 0 ≦ g ≦ 1, 0 ≦ h ≦ 1, 0 ≦ g + h ≦ 1), and includes at least one of them, but is not limited thereto. Specifically, the oxide-based positive electrode active material may include one or more of LiCoO2, LiNiO2, and LiMn2O4, but is not limited thereto. In another example of the present application, the sulfide-based positive electrode active material includes TiS2, V2S3, FeS, FeS2, WS2, LiJS i (J is at least one selected from the group consisting of Ti, Fe, Ni, Cu, and Mo, 1 ≦ i ≦ 2.5), etc., and may include at least one of them, but is not limited thereto. In still another example of the present application, the polyanion-based positive electrode active material may include at least one of LiFePO4, Li3V2(PO4)3, Li3V3(PO4)3, and LiVPO4F, but is not limited thereto.

[0056] In the embodiments of the present application, the particle size of the positive electrode active material is 100 nm to 500 μm. Specifically, the particle size of the positive electrode active material may be, but is not limited to, 100 nm to 100 μm, 100 nm to 50 μm, 500 nm to 50 μm, etc.

[0057] In the embodiments of the present application, in order to optimize the interface between the positive electrode material layer 201 and the solid electrolyte, reduce the interface resistance, and improve the cycle stability, the surface of the positive electrode active material may have a coating layer. Specifically, the coating layer on the surface of the positive electrode active material may include, but is not limited to, LiNbO3, LiTaO3, Li3PO4, Li4Ti5O 12 etc., but is not limited thereto.

[0058] In the present application, the binder for the positive electrode in the positive electrode material layer 201 is not particularly limited. For example, it may include at least one of a fluorine-containing resin, polyvinylidene fluoride, polytetrafluoroethylene, polyvinyl alcohol, polyolefin, styrene-butadiene rubber, etc., but is not limited thereto. The conductive agent in the positive electrode material layer 201 is not particularly limited, and conventional materials in this field may be used. For example, the conductive agent may include at least one of conductive carbon black (e.g., acetylene black, ketjen black), carbon nanotubes, carbon fibers, and graphite, but is not limited thereto. In one embodiment of the present application, the mass percentage content of the binder for the positive electrode in the positive electrode material layer 201 is 0.01% to 10%. Specifically, the mass percentage content of the binder for the positive electrode in the positive electrode material layer 201 may be, but is not limited to, 0.015% to 8%, 0.02% to 7%, 0.02% to 5%, or 0.05% to 4.5%, etc. In another embodiment of the present application, the mass percentage content of the conductive agent in the positive electrode material layer 201 is 0.1% to 20%. Specifically, the mass percentage content of the conductive agent in the positive electrode material layer 201 may be, but is not limited to, 0.5% to 18%, 1 to 15%, 1 to 10%, or 3 to 8.5%, etc.

[0059] In an embodiment of the present application, the negative electrode current collector 102 and the positive electrode current collector 202 are independently selected from a metal foil material or an alloy foil material. The metal foil material includes, but is not limited to, copper, titanium, aluminum, platinum, iridium, ruthenium, nickel, tungsten, tantalum, gold, or silver foil materials. The alloy foil material includes, but is not limited to, stainless steel or an alloy containing at least one element among copper, titanium, aluminum, platinum, iridium, ruthenium, nickel, tungsten, tantalum, gold, and silver. For example, specifically, the negative electrode current collector 102 may be an aluminum foil, and the positive electrode current collector 202 may be a copper foil. In the present application, the thickness and surface roughness of the negative electrode current collector 102 and the positive electrode current collector 202 can be adjusted according to actual needs.

[0060] In an embodiment of the present application, the solid electrolyte layer 300 is formed by applying and drying a slurry containing a solid electrolyte material and a solvent, and the components of the solid electrolyte layer 300 include the solid electrolyte material. In another embodiment of the present application, the solid electrolyte layer 300 may include a binder, and the material thereof may be selected from the binders in the positive electrode material layer 201, and the description thereof is omitted here. In an example of the present application, the solid electrolyte layer 300 may be combined with the negative electrode material layer 101 by coating, and further, the solid electrolyte layer 300 may be combined with the positive electrode 200 having the positive electrode material layer 201 by pressing.

[0061] In the embodiments of the present application, the solid electrolyte material for the positive electrode and the solid electrolyte material in the solid electrolyte layer 300 are each independently one or more selected from the group consisting of NASICON-type solid electrolytes, garnet-type solid electrolytes, perovskite-type solid electrolytes, and sulfur-based solid electrolytes. The material of the solid electrolyte layer 300 may be the same as or different from the solid electrolyte material for the positive electrode. For example, by selecting a solid electrolyte material with reduction resistance as the component of the solid electrolyte layer, the negative electrode material 10 of the negative electrode 100 is protected, and the cycle stability of the negative electrode material 10 is further improved. Further, when manufacturing the solid electrolyte layer 300 and the positive electrode material layer 201, the particle size of the solid electrolyte material used may be 1 nm to 5 μm. In one embodiment of the present application, the NASICON-type solid electrolyte may include one or more of LiM2(PO4)3 and its dopants, but is not limited thereto, M is Ti, Zr, Ge, Sn, or Pb, and the dopant elements used for the dopant are one or more selected from the group consisting of Mg, Ca, Sr, Ba, Sc, Al, Ga, In, Nb, Ta, and V. In another embodiment of the present invention, the chemical formula of the garnet-type solid electrolyte is Li 7+p-q-3u Al u La 3-p X p Zr 2-q Y q O 12 where 0 < p ≤ 1, 0 < q ≤ 1, 0 < u ≤ 1, X is at least one selected from the group consisting of La, Ca, Sr, Ba, and K, and Y is at least one selected from the group consisting of Ta, Nb, W, and Hf. In another embodiment of the present invention, the chemical formula of the perovskite-type solid electrolyte is A 1 x1 B 1 y1 TiO3, A 1 x2 B 2 y2 Ta2O6, A 3 x3 B 3 y3 Nb2O6 or A c E d D e Ti fIt is O3, x1 + 3y1 = 2, 0 < x1 < 2, 0 < y1 < 2 / 3, x2 + 3y2 = 2, 0 < x2 < 2, 0 < y2 < 2 / 3, x3 + 3y3 = 2, 0 < x3 < 2, 0 < y3 < 2 / 3, c + 2d + 5e + 4f = 6, and c, d, e, f are all greater than 0, A 1 , A 2 , and A 3 is independently at least one selected from the group consisting of Li and Na, B 1 , B 2 , and B 3 is independently at least one selected from the group consisting of La, Ce, Pr, Y, Sc, Nd, Sm, Eu, and Gd, E is at least one selected from the group consisting of Sr, Ca, Ba, Ir, and Pt, and D is at least one selected from the group consisting of Nb and Ta. In another embodiment of the present application, the sulfur-based solid electrolyte includes, but is not limited to, one or more of crystalline Li r Q s P t1 S z , glassy Li2S-P2S5, glass-ceramic Li2S-P2S5, and one or more of its dopants. In crystalline Li r Q s P t1 S z , Q is one or more selected from the group consisting of Si, Ge, and Sn, and r + 4s + 5t1 = 2z, 0 ≤ s ≤ 1.5. Glassy Li2S-P2S5 contains different products composed of Li2S and P2S5, for example, Li7P3S 11 or 70Li2S-30P2S5, etc.

[0062] In an embodiment of the present invention, a method for manufacturing an all-solid-state lithium battery is further provided, including the following steps S201 to S204.

[0063] In step S201, the negative electrode 100 is manufactured, that is, the negative electrode material 10 and the first solvent are mixed to obtain a negative electrode mixed slurry, and the negative electrode mixed slurry is applied to the negative electrode current collector 102, dried, and press-treated to obtain the negative electrode 100.

[0064] In step S202, the solid electrolyte layer 300 is manufactured, that is, in an atmosphere of a protective gas, a solid electrolyte material and a second solvent are uniformly mixed to obtain a solid electrolyte mixed slurry, the solid electrolyte mixed slurry is continuously applied to the negative electrode, and after drying, the solid electrolyte layer 300 is formed on the negative electrode 100.

[0065] In step S203, the positive electrode 200 is manufactured, that is, a positive electrode active material, a solid electrolyte for positive electrode, a conductive agent, a binder for positive electrode and a third solvent are uniformly mixed to obtain a positive electrode mixed slurry, the positive electrode mixed slurry is applied to the positive electrode current collector 202, dried, and subjected to a pressing process to obtain the positive electrode 200.

[0066] In step S204, in an atmosphere of a protective gas, the negative electrode 100 having the solid electrolyte layer 300 and the manufactured positive electrode 200 are aligned, tabs are bonded, and after hot pressing treatment, vacuum sealing and hydrostatic pressure pressing treatment, a all-solid-state lithium battery is obtained.

[0067] In the embodiment of the present application, the first solvent, the second solvent and the third solvent are each independently at least one selected from the group consisting of water, ethanol, toluene, xylene, anisole, acetonitrile, heptane, decane, ethyl acetate, ethyl propionate, butyl butyrate, N-methylpyrrolidone, acetone and the like. The usage amount of each solvent may generally be 50 wt% to 400 wt% of the mass of the dry material for preparing the corresponding mixed slurry.

[0068] In the embodiment of the present application, the pressing may be a roll pressing treatment at 0 to 5 MPa, but is not limited thereto.

[0069] In the embodiment of the present application, the temperature of the hot pressing treatment may be about 100°C, but is not limited thereto, the time of the hot pressing treatment may be 0.5 h to 3 h, but is not limited thereto, the pressure of the hydrostatic pressure pressing may be 100 MPa or more, but is not limited thereto. For example, the pressure is 100 MPa to 300 MPa, and the time of the hydrostatic pressure pressing treatment may be 3 min to 10 min, but is not limited thereto.

[0070] Since the all-solid-state lithium battery according to the present application contains the above negative electrode material 10, the battery capacity of the all-solid-state lithium battery is high, the cycle performance is high, which is advantageous for its application.

[0071] Hereinafter, the embodiments of the present application will be further described by dividing them into a plurality of embodiments.

Embodiment

[0072] The manufacturing method of the all-solid-state lithium battery includes the following steps (1) to (4).

[0073] Step (1), manufacturing of the negative electrode sheet Under an argon gas atmosphere, 31 g of Li2S, 60 g of P2S5, 7 g of SiS2, 2 g of P2O5, and 1000 g of Li 2.3 Si were put into a ball mill pot, an appropriate amount of ZrO2 beads were added, and after high-energy ball milling at a rotation speed of 200 rpm for 2 h, it was transferred to an electric heating furnace (under a protective atmosphere), heated to 300 °C at a heating rate of 10 °C / min or more, and held for 30 min to obtain a glassy solid electrolyte composed of Li2S, P2S5, SiS2, and P2O5, and an amorphous Li 2.3 core containing Si particles dispersed therein.

[0074] 1000 g of Li 1.71 Si were put into a ball mill pot, an appropriate amount of ZrO2 beads were added, and high-energy ball milling was performed at a rotation speed of 250 rpm for 0.5 h to obtain an amorphous Li 1.71 Si alloy, and 1000 g of the core, 50 g of amorphous Li 1.71 Si alloy, and 1000 g of toluene solvent were put into a ball mill pot, an appropriate amount of ZrO2 beads were added, and ball milling was performed at a rotation speed of 50 rpm for 30 min to obtain a negative electrode material which is a core coated with an amorphous Li 1.71 Si alloy layer. When the particle sample was cut by a focused ion beam (FIB) and observed with a scanning electron microscope (SEM), the average particle size of the amorphous Li 2.3 Si particles was about 50 nm, and the amorphous Li1.71 It was found that the average thickness of the Si alloy layer was about 250 nm and the average particle size of the entire negative electrode particles was about 1 μm.

[0075] 1000 g of the negative electrode material, 30 g of the SBR rubber-based binder, and 1500 mL of the toluene solution were put into a disperser and dispersed for 30 min to form a stable and uniform negative electrode slurry. After the negative electrode slurry was intermittently and uniformly coated on a copper foil (width 160 mm, thickness 16 μm), it was dried at 373 K and pressed by a roll press to obtain a negative electrode.

[0076] Step (2), manufacturing of the solid electrolyte layer Under an argon gas atmosphere, 600 g of the 70Li2S·30P2S5 glassy solid electrolyte material was put into 1200 g of the toluene solution containing 30 g of the butadiene rubber-based binder, and heated and stirred until a stable and uniform slurry was obtained. After the slurry was continuously coated on the negative electrode obtained in step (1), it was dried at 373 K to form a solid electrolyte layer with a thickness of 50 μm on the negative electrode.

[0077] Step (3), manufacturing of the positive electrode 1000 g of LiCoO2, 51 mL of niobium ethoxide, 12 g of lithium ethoxide, 1000 mL of deionized water, and 1000 mL of ethanol were sufficiently mixed. While continuously stirring, aqueous ammonia was dropped to adjust the pH to 10, the solution was evaporated to dryness, and the obtained powder was heated at 400 °C for 8 h to obtain a LiCoO2 positive electrode active material coated with LiNbO3 on the surface.

[0078] 1000 g of the LiCoO2 positive electrode active material coated with the above LiNbO3, 150 g of Li 10 GeP2S 12A solid electrolyte material, 30 g of a butadiene rubber binder, 20 g of acetylene black, and 20 g of carbon fiber were placed in 1500 g of a toluene solvent, and then stirred with a vacuum mixer to form a stable and uniform positive electrode mixed slurry. After the positive electrode mixed slurry was uniformly and intermittently coated on an aluminum foil (width 160 mm, thickness 16 μm), it was dried at 393 K, pressed with a roll press, and a positive electrode material layer with a thickness of 100 μm was formed on the aluminum foil to obtain a positive electrode.

[0079] Step (4), manufacturing of an all-solid-state lithium battery Under a protective atmosphere, the above positive electrode and a negative electrode having a solid electrolyte layer were aligned, placed in a press, the tabs were bonded together, hot-pressed at 100 °C for 1 h, vacuum-sealed with an aluminum plastic film, and finally pressed with a hydrostatic press at 200 MPa for 300 s to obtain an all-solid-state lithium battery.

Example

[0080] The manufacturing method of the all-solid-state lithium battery according to this example is that Li 2.3 Si is replaced with Li 4.4 Si, Li 1.71 Si is replaced with Li 3.75 Si, and the LiCoO2 positive electrode active material coated with LiNbO3 is replaced with TiS2, which is almost the same as Example 1. When the particle sample was cut by a focused ion beam (FIB) and observed with a scanning electron microscope (SEM), it was found that the average particle size of the amorphous Li 4.4 Si particles was about 75 nm, the average thickness of the amorphous Li 3.75 Si alloy layer was about 350 nm, and the average particle size of the entire negative electrode particles was about 1.3 μm.

Example

[0081] The manufacturing method of the all-solid-state lithium battery according to this example is 12.4 g of Li2S, 24 g of P2S5, 2.8 g of SiS2, 0.8 g of P2O5, and 1000 g of Li 2.3Put Si into a ball mill pot, add an appropriate amount of ZrO2 beads, and perform high-energy ball milling at a rotational speed of 150 rpm for 0.3 h. Then transfer it to an electric heating furnace (under a protective atmosphere), heat it to 300 °C at a heating rate of 10 °C / min or more, and hold for 30 min to obtain the core. Except for this, it is almost the same as Example 1, and the other steps were not changed. When the particle sample was cut by a focused ion beam (FIB) and observed with a scanning electron microscope (SEM), amorphous Li 2.3 The average particle size of Si particles was about 1.2 μm, and amorphous Li 1.71 The average thickness of the amorphous LiSi alloy layer was about 5 μm, and it was found that the average particle size of the entire negative electrode particles was about 30 μm.

[0082] To emphasize the beneficial effects of the examples of the present invention, the following comparative examples are provided. (Comparative Example 1)

[0083] The manufacturing method of the all-solid-state lithium battery according to this comparative example is the same as that of Example 1 except that a silicon negative electrode material coated with carbon is used instead of the negative electrode material. The manufacturing method of the silicon negative electrode material coated with carbon is as follows: Put 1000 g of Si and 240 g of sucrose into 1000 mL of deionized water and stir evenly. Then heat to 100 °C while stirring, evaporate the water, take out the solid matter, and heat it to 300 °C under an inert atmosphere to obtain a silicon negative electrode material coated with carbon. The silicon negative electrode material coated with carbon was used as the negative electrode as it was, and the other steps were not changed. (Comparative Example 2)

[0084] The manufacturing method of the all-solid-state lithium battery according to this comparative example is the same as that of Example 1 except for step (1). The specific operations of step (1) are as follows. 1000 g of Si and 240 g of sucrose are put into 1000 mL of deionized water and stirred uniformly. Then, while stirring, it is heated to 100 °C, and after the water is evaporated, the solid is taken out and heated to 300 °C in an inert atmosphere to obtain a silicon negative electrode material coated with carbon. 1000 g of the silicon negative electrode material coated with carbon, 150 g of the 70Li2S·30P2S5 glassy electrolyte material, 100 g of acetylene black, and 1500 mL of toluene are prepared into a mixed slurry, coated on a copper foil, dried, and pressed to obtain a negative electrode. The other steps were not changed. (Comparative Example 3)

[0085] In the manufacturing method of the all-solid-state lithium battery according to this comparative example, in step (1), 1000 g of the core and 50 g of amorphous Li 1.71 Si are directly mixed with 30 g of an SBR rubber-based binder and 1500 mL of a toluene solution to form a negative electrode slurry. Except for not coating 50 g of amorphous Li 1.71 Si on 950 g of the core, it is the same as Example 1, and the other steps were not changed. (Comparative Example 4)

[0086] In the manufacturing method of the all-solid-state lithium battery according to this comparative example, in step (1), 310 g of Li2S, 600 g of P2S5, 70 g of SiS2, and 20 g of P2O5 are put into a ball mill pot, an appropriate amount of ZrO2 beads are added, and after high-energy ball milling at a rotation speed of 200 rpm for 2 h, it is transferred to an electric heating furnace and heated to 300 °C at a heating rate of 10 °C / min or more, and held for 30 min to obtain a glassy solid electrolyte. Except for directly mixing 90 g of the glassy solid electrolyte, 910 g of Li 2.3 Si, and 50 g of Li 1.71 Si with 30 g of an SBR rubber-based binder and 1500 mL of a toluene solution to form a negative electrode slurry, it is the same as Example 1, and the other steps were not changed. (Comparative Example 5)

[0087] The manufacturing method of the all-solid-state lithium battery according to this comparative example is the same as that of Example 1 except that in step (1), after obtaining the core, it is directly coated on the negative electrode sheet, and amorphous Li 1.71 Si is not coated, and the other steps remain unchanged.

[0088] Performance test The battery cycle life test was conducted on the all-solid-state lithium batteries obtained in Examples 1 to 3 and Comparative Examples 1 to 5 above. The test method is as follows. Twenty all-solid-state lithium battery samples obtained in each example and comparative example were taken, and in a LAND CT 2001C secondary battery performance detection device, under the condition of 298 ± 1K, a charge-discharge cycle test was conducted on each battery at a rate of 0.1C.

[0089] The test steps are as follows. Leave it for 10 min, charge it at a constant voltage until it is cut off at 4.25V / 0.05C, leave it for 10 min, and discharge it at a constant current until 3V. This is one cycle, and the discharge capacity of the first cycle was recorded (using TiS2 as the positive electrode, the upper and lower limit values of the voltage are 3V / 0.05C and 1V respectively, and the other conditions are the same). Repeat the above cycle steps. When the battery capacity during the cycle is lower than 80% of the first discharge capacity, end the cycle. The number of cycles at the end of the cycle is the cycle life of the battery. Take the average value of each group, and the obtained results are shown in Table 1.

Table 1

[0090] As can be seen from Table 1, both the discharge capacity and cycle life of Comparative Example 1 are very poor. The discharge capacity and cycle life of Comparative Examples 2 to 4 are clearly lower than those of Examples 1 to 3. Comparative Example 1 of a silicon negative electrode material coated with ordinary carbon in a lithium battery using an electrolyte shows extremely poor battery performance, indicating that the negative electrode material is not suitable for all-solid-state lithium batteries. However, when the silicon negative electrode material coated with the carbon and a solid electrolyte are mixed (Comparative Example 2), the performance of the manufactured battery is improved compared to Comparative Example 1, but it is still far lower than that of the all-solid-state lithium batteries manufactured with the negative electrode materials of Examples 1 to 3 of the present application. The battery manufactured with the negative electrode material formed by directly mixing without manufacturing a core and without coating (Comparative Example 4) has an improved discharge capacity, but still has poor cycle performance. The cycle performance of the battery manufactured with the negative electrode material formed by directly using the core (Comparative Example 5) is slightly improved compared to Comparative Example 4, but the discharge capacity is slightly decreased. The battery manufactured with the negative electrode material formed by directly using the core and without coating (Comparative Example 3) has slightly improved discharge capacity and cycle performance compared to Comparative Example 4, but is not significantly improved and is far lower than the performance of the all-solid-state lithium batteries manufactured with the negative electrode materials of Examples 1 to 3 of the present application. Thereby, it is shown that the all-solid-state lithium battery manufactured using the negative electrode material of the present invention has a high discharge specific capacity of the negative electrode, a good cycle life of the battery, and is advantageous for wide use.

[0091] As described above, the embodiments of the present application have been described with reference to the drawings. However, the present application is not limited to the above specific embodiments. The above specific embodiments are not restrictive but merely illustrative. A person skilled in the art can, under the suggestion of the present application, make many forms without departing from the spirit of the present application and the protection scope of the claims, and all of these belong to the protection scope of the present application.

Description of Reference Signs

[0092] 11 Core 111 Glassy Solid Electrolyte 112 Amorphous Lithium Silicon Alloy Particles 12 Amorphous Lithium Silicon Alloy Layer 10 Negative electrode material 101 Negative electrode material layer 102 Negative electrode current collector 100 Negative electrode 201 Positive electrode material layer 202 Positive electrode current collector 200 Positive electrode 300 Solid electrolyte layer

Claims

1. It includes a core and an amorphous lithium silicon alloy layer covering the core. The core includes a glassy solid electrolyte and amorphous lithium silicon alloy particles dispersed in the glassy solid electrolyte. The material of the amorphous lithium silicon alloy particles is Li ｘ Si, where 0 < x ≤ 4.

4. The material of the amorphous lithium silicon alloy layer is Li ｙ Si, where 0 < y ≤ 4.

4. It is a negative electrode material.

2. The mass ratio of the amorphous lithium silicon alloy particles to the amorphous lithium silicon alloy layer is (1 to 100):

1. The negative electrode material according to Claim 1.

3. In the core, the mass fraction of the amorphous lithium silicon alloy particles is 50% to 95%. The negative electrode material according to Claim 1 or 2.

4. The particle size of the amorphous lithium silicon alloy particles is 10 nm to 1 μm, the thickness of the amorphous lithium silicon alloy layer is 5 nm to 1 μm, and the particle size of the negative electrode material is 20 nm to 20 μm. The negative electrode material according to any one of Claims 1 to 3.

5. The glassy solid electrolyte contains at least one of a glassy oxide solid electrolyte and a glassy sulfide solid electrolyte. The negative electrode material according to any one of Claims 1 to 4.

6. The glassy solid electrolyte is in mole percentage. 30 mol% to 80 mol% of Li ２ S, 10 mol% to 50 mol% of P ２ S ５ , 0 mol% to 30 mol% of SiS ２ and 0 mol% to 30 mol% of LiA, where A is at least one of Cl, Br, and I, or 30 mol% to 80 mol% of Li ２ O, 10 mol% to 50 mol% of P ２ O ５ , 0 mol% to 30 mol% of SiS ２ and 0 mol% to 30 mol% of LiA, where A is at least one of Cl, Br, and I, or 30 mol% to 80 mol% of Li ２ O, 20 mol% to 60 mol% of B ２ O ３ and contains 0 mol% to 30 mol% of LiA, where A is at least one of Cl, Br, and I, or 30 mol% to 80 mol% of Li ２ S, 20 mol% to 60 mol% of SiS ２ and contains 0 mol% to 30 mol% of LiA, where A is at least one of Cl, Br, and I, or 30 mol% to 85 mol% of Li ２ O and 15 mol% to 70 mol% of LiA, where A is at least one of Cl, Br, and I, the negative electrode material according to any one of claims 1 to 5.

7. Amorphous Li ｘ Dispersing Si (0 < x ≤ 4.4) particles in a glassy solid electrolyte to obtain a core Coating the core with amorphous Li ｙ Si (0 < y ≤ 4.4) to obtain a negative electrode material, and a method for manufacturing a negative electrode material including the step.

8. Coating the core with amorphous Li ｙ The step of coating with Si Li ｙ Ball-milling Li ｙ Si to obtain the amorphous Li Si and a step of obtaining The core and the amorphous Li ｙ Si are mixed and ball-milled to coat the core with the amorphous Li ｙ Si, the method according to claim 7, comprising the step of.

9. A all-solid-state lithium battery including a positive electrode, a negative electrode, and a solid electrolyte layer positioned between the positive electrode and the negative electrode, wherein the negative electrode contains the negative electrode material according to any one of Claims 1 to 6.

10. The negative electrode includes a negative electrode current collector and a negative electrode material layer provided on the negative electrode current collector. The negative electrode material layer contains the negative electrode material and does not contain a conductive agent. The all-solid-state lithium battery according to Claim 9.

11. A method for manufacturing an all-solid-state lithium battery, The all-solid-state lithium battery includes a positive electrode, a negative electrode, and a solid electrolyte layer positioned between the positive electrode and the negative electrode. The method for manufacturing an all-solid-state lithium battery includes the method for manufacturing the negative electrode material according to any one of Claims 7 to 8. The method for manufacturing an all-solid-state lithium battery.

12. The negative electrode includes a negative electrode current collector and a negative electrode material layer provided on the negative electrode current collector. The negative electrode material layer contains the negative electrode material and does not contain a conductive agent. The method for manufacturing an all-solid-state lithium battery according to Claim 11.

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