All-solid-state lithium-ion secondary battery and production method thereof

1. An all-solid-state lithium-ion secondary battery comprising:

an anode;

a cathode;

a solid electrolyte layer disposed between the anode and the cathode; and

at least one of a first intermediate layer disposed between the anode and the solid electrolyte layer, and a second intermediate layer disposed between the cathode and the solid electrolyte layer,

wherein:

at least one of a particle size of the first intermediate layer and a particle size of the second intermediate layer is smaller than those of the anode, the cathode, and the solid electrolyte layer,

the anode contains a composite material,

the composite material comprises a porous carbon material and at least one material selected from the group consisting of a metal, an alloy of a metal, and an oxide of a metal,

the at least one material is supported in a pore of the porous carbon material, and

the first and second intermediate layers have a thickness of 0.01 to 10 μm.

2. The all-solid-state lithium-ion secondary battery according to claim 1 , wherein

the first intermediate layer contains a constituent material of the anode and/or a constituent material of the solid electrolyte layer, and

the second intermediate layer contains a constituent material of the cathode and/or a constituent material of the solid electrolyte layer.

3. The all-solid-state lithium-ion secondary battery according to claim 1 , wherein the first intermediate layer and/or the second intermediate layer contains a constituent material of the solid electrolyte layer.

4. The all-solid-state lithium-ion secondary battery according to claim 1 , which is obtained by a production method of an all-solid-state lithium-ion secondary battery comprising:

a primary sintered body forming step of forming a primary sintered body of anode, a primary sintered body of cathode, and a primary sintered body of solid electrolyte layer;

a laminate forming step of disposing the primary sintered body of solid electrolyte layer between the primary sintered body of anode and the primary sintered body of cathode, and disposing at least one of an undried first precursor layer formed by application of a first sol intermediate layer precursor on a surface of the primary sintered body of anode nearer to the primary sintered body of solid electrolyte layer or on a surface of the primary sintered body of solid electrolyte layer nearer to the primary sintered body of anode, and an undried second precursor layer formed by application of a second sol intermediate layer precursor on a surface of the primary sintered body of cathode nearer to the primary sintered body of solid electrolyte layer or on a surface of the primary sintered body of solid electrolyte layer nearer to the primary sintered body of cathode, thereby forming a laminate; and

a firing step of firing the laminate to obtain a sintered body comprising an anode resulting from refiring of the primary sintered body of anode, a cathode resulting from refiring of the primary sintered body of cathode, and a solid electrolyte layer disposed between the anode and the cathode and resulting from refiring of the primary sintered body of solid electrolyte layer, and comprising at least one of a first intermediate layer disposed between the anode and the solid electrolyte layer and resulting from firing of the first precursor layer, and a second intermediate layer disposed between the cathode and the solid electrolyte layer and resulting from firing of the second precursor layer.

5. The all-solid-state lithium-ion secondary battery according to claim 1 , wherein the metal is at least one metal selected from the group consisting of Sn, Si, Al, Ge, Sb, Ag, Ga, In, Fe, Co, Ni, Ti, Mn, Ca, Ba, La, Zr, Ce, Cu, Mg, Sr, Cr, Mo, Nb, V, and Zn.

6. The all-solid-state lithium-ion secondary battery according to claim 1 , wherein the composite material comprises the porous carbon material and an alloy of FeSn supported in the pore of the porous material.

7. The all-solid-state lithium-ion secondary battery according to claim 1 , wherein an average pore size of the porous carbon material is not more than 5 nm.

8. The all-solid-state lithium-ion secondary battery according to claim 1 , wherein an average primary particle size of the at least one material is not less than 10 nm nor more than 500 nm.

9. The all-solid-state lithium-ion secondary battery according to claim 1 , wherein the battery has a high-rate discharge characteristic of at least 65%.

10. The all-solid-state lithium-ion secondary battery according to claim 1 , wherein the battery has a capacity retention rate after 500 cycles of at least 79%.