All-solid secondary battery, multilayered all-solid secondary battery, and method of manufacturing all-solid secondary battery

1. An all-solid secondary battery, comprising:

a first current collector;

a pair of first active material layers respectively disposed on opposite sides of the first current collector;

a pair of solid electrolyte layers respectively disposed on surfaces of the pair of first active material layers, wherein the surfaces of the pair of first active material layers are each opposite to a surface of the first current collector;

a pair of second active material layers respectively disposed on surfaces of the pair of solid electrolyte layers, wherein the surfaces of the pair of solid electrolyte layers are each opposite to a surface of the pair of first active material layers; and

a pair of second current collectors respectively disposed on surfaces of the pair of second active material layers, wherein the surfaces of the pair of second active material layers are each opposite to a surface of the pair of solid electrolyte layers,

wherein a surface of one of the pair of second current collectors that is opposite to a surface of one of the pair of second active material layers, does not comprise protrusions having a height of greater than about 8 micrometers, and

wherein a surface of the other one of the pair of second current collectors that is opposite to a surface of the other one of the pair of second active material layers, comprises protrusions having a height of greater than about 8 micrometers at a content of greater than 0 to about 1 protrusion per square centimeter.

2. The all-solid secondary battery of claim 1 ,

wherein the surface of the one of the pair of second current collectors does not comprise protrusions having a height of greater than about 5 micrometers.

3. The all-solid secondary battery of claim 1 ,

wherein the surface of the other one of the pair second current collectors does not comprise protrusions having a height of greater than about 10 micrometers.

4. The all-solid secondary battery of claim 1 ,

wherein each one of the pair of first active material layers is a positive electrode active material layer, and each one of the pair of second active material layers is a negative electrode active material layer.

5. The all-solid secondary battery of claim 4 ,

wherein the positive electrode active material layer comprises a positive electrode active material and a solid electrolyte.

6. The all-solid secondary battery of claim 4 ,

wherein the positive electrode active material layer comprises a lithium salt of a transition metal oxide having a layered rock salt type structure.

7. The all-solid secondary battery of claim 4 ,

wherein the positive electrode active material layer comprises a compound represented by LiNi x Co y Al z O 2 or LiNi x Co y Mn z O 2 , wherein 0<x<1, 0<y<1, 0<z<1, and x+y+z=1.

8. The all-solid secondary battery of claim 1 ,

wherein each one of the pair of second active material layers comprises a negative electrode active material which forms an alloy with lithium and a negative electrode active material which forms a compound with lithium, or a combination thereof, and

lithium metal precipitates on each one of the pair of second active material layers through the negative electrode active material during charging.

9. The all-solid secondary battery of claim 1 ,

wherein a ratio of a charging capacity of one of the pair of first active material layers to a charging capacity of one of the pair of second active material layers is represented by Formula (1) below:

0.002 <b/a <0.5,  Formula (1)

wherein, a is a charging capacity of the one of the pair of first active material layers, and b is a charging capacity of the one of the pair of second active material layers.

10. The all-solid secondary battery of claim 1 ,

wherein each one of the pair of second active material layers amorphous carbon, gold, platinum, palladium, silicon, silver, aluminum, bismuth, tin, zinc, or a combination thereof.

11. The all-solid secondary battery of claim 1 ,

wherein each one of the pair of second active material layers comprises a binder.

12. The all-solid secondary battery of claim 11 ,

wherein the binder comprises styrene butadiene rubber, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene oxide, or a combination thereof.

13. The all-solid secondary battery of claim 1 ,

wherein each one of the pair of solid electrolyte layers comprises a sulfide-containing solid electrolyte material.

14. The all-solid secondary battery of claim 1 ,

wherein each one of the pair of solid electrolyte layers comprises a solid electrolyte comprising sulfur, silicon, phosphorus, boron, or a combination thereof.

15. The all-solid secondary battery of claim 1 ,

wherein each one of the pair of second current collectors comprises copper, stainless steel, titanium, nickel, an alloy thereof, or a combination thereof.

16. A multilayered all-solid secondary battery, comprising:

at least one insulating layer; and

a plurality of the all-solid secondary batteries of claim 1 ,

wherein the plurality of the all-solid secondary batteries is disposed such that the at least one insulating layer is interposed between the all-solid secondary batteries,

wherein the all-solid secondary batteries are disposed such that one of the pair of second current collectors of one of the plurality of all-solid secondary batteries faces one of the pair of the second current collectors of another one of the all-solid secondary batteries.

17. The multilayered all-solid secondary battery of claim 16 ,

wherein the at least one insulating layer comprises polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyurethane, polytetrafluoroethylene, acrylic resin, phenol resin, epoxy resin, melamine resin, urethane resin, polyamide, polycarbonate, silicon rubber, urethane rubber, paper, or a combination thereof.

18. The multilayered all-solid secondary battery of claim 16 ,

wherein the at least one insulating layer has a thickness of about 0.1 micrometers to about 100 micrometers.

19. A method of manufacturing an all-solid secondary battery, comprising a first current collector, a pair of first active material layers disposed on opposite sides of the first current collector, a pair of solid electrolyte layers disposed on opposite sides of the first current collector and on surfaces of the pair of first active material layers, wherein the surfaces of the pair of first active material layers are each opposite to a surface of the first current collector, a pair of second active material layers on opposite sides of the first current collector and on surfaces of the pair of solid electrolyte layers, wherein the surfaces of the pair of solid electrolyte layers are each opposite to a surface of one of the pair of first active material layers, and a pair of second current collectors disposed on opposite sides of the first current collector and on surfaces of the pair of second active material layers, wherein the surfaces of the pair of second active material layers are each opposite to one of the pair of solid electrolyte layers, the method comprising:

forming each one of the pair of solid electrolyte layers on one of the pair of first active material layers or on one of the pair second active material layers; and

disposing a support on a side of a laminate in which the first current collector, the pair of first active material layers, the pair of solid electrolyte layers, the pair of second active material layers, and the pair of second current collectors are stacked, and

isostatically pressing the laminate.

20. The method of claim 19 ,

wherein the isostatic pressing of the laminate comprises applying a pressure of about 10 megapascals to about 1000 megapascals for about 1 minute to about 120 minutes.