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

1. An all-solid secondary battery comprising:

a cathode layer comprising a cathode active material layer;

an anode layer; and

a solid electrolyte layer comprising a solid electrolyte, wherein the solid electrolyte layer is disposed between the cathode layer and the anode layer,

wherein the anode layer comprises:

an anode current collector, a first anode active material layer in contact with the solid electrolyte layer, and

a second anode active material layer disposed between the anode current collector and the first anode active material layer,

a third anode active material layer disposed between the anode current collector and the second anode active material layer or between the first anode active material layer and the second anode active material layer,

wherein the third anode active material layer is a metal layer comprising lithium or a lithium alloy,

wherein the first anode active material layer comprises a first carbonaceous anode active material, and the second anode active material layer comprises a second carbonaceous anode active material, and

a first intensity ratio of an intensity of a D band peak to an intensity of a G band peak in a Raman spectrum of the first carbonaceous anode active material is less than a second intensity ratio of an intensity of a D band peak to an intensity of a G band peak in a Raman spectrum of the second carbonaceous anode active material.

2. The all-solid secondary battery of claim 1 , wherein the first ratio is about 0.1 to about 0.95, and

the second ratio is about 1.0 to about 10.

3. The all-solid secondary battery of claim 1 , wherein a position of a D band peak center in the Raman spectrum of the first carbonaceous anode active material exhibits a blue shift of about 2 cm −1 to about 4 cm −1 with respect to a position of a D band peak center in the Raman spectrum of the second carbonaceous anode active material,

wherein a position of a G band peak center in the Raman spectrum of the first carbonaceous anode active material exhibits a blue shift of about 1 cm −1 to about 3 cm −1 with respect to a position of a G band peak center in the Raman spectrum of the second carbonaceous anode active material, and

wherein a full width at half maximum of the D band peak of the first carbonaceous anode active material is about 50% to about 80% less than a full width at half maximum of the D band peak of the second carbonaceous anode active material.

4. The all-solid secondary battery of claim 1 , wherein at least one of the first carbonaceous anode active material or the second carbonaceous anode active material is in a form of particles, and

wherein the particles have an average particle diameter of about 10 nm to about 4 micrometers or less.

5. The all-solid secondary battery of claim 1 , wherein at least one of the first carbonaceous anode active material or the second carbonaceous anode active material comprises amorphous carbon.

6. The all-solid secondary battery of claim 1 , wherein at least one of the first anode active material layer or the second anode active material layer consists of the first carbonaceous anode active material or the second carbonaceous anode active material, respectively.

7. The all-solid secondary battery of claim 1 , wherein at least one of the first anode active material layer or the second anode active material layer further comprises a metal or metalloid anode active material comprising a metal, a metalloid, or a combination thereof.

8. The all-solid secondary battery of claim 7 , wherein the metal or metalloid anode active material comprises at least one of indium, silicon, gallium, tin, aluminum, titanium, zirconium, niobium, germanium, antimony, bismuth, gold, platinum, palladium, magnesium, silver, or zinc.

9. The all-solid secondary battery of claim 7 , wherein each of the first anode active material layer and the second anode active material layer further comprises the metal or metalloid anode active material, and

wherein an amount of the metal or metalloid anode active material in the second anode active material layer is greater than an amount of the metal or metalloid anode active material in the first anode active material layer.

10. The all-solid secondary battery of claim 7 , wherein the first anode active material layer comprises a composite of first particles and second particles, wherein the first particles consist of the first carbonaceous material and the second particles consist of the metal or metalloid anode active material,

wherein the first carbonaceous material is amorphous carbon, and

wherein an amount of the second particles is about 1 weight percent to about 60 weight percent, based on a total weight of the composite.

11. The all-solid secondary battery of claim 10 , wherein the second anode active material layer comprises a mixture of first particles and second particles,

wherein the first particles consist of the second carbonaceous material and the second particles consist of the metal or metalloid anode active material,

wherein the second carbonaceous material is amorphous carbon, and

wherein an amount of the second particles is about 1 weight percent to about 60 weight percent based on a total weight of the mixture.

12. The all-solid secondary battery of claim 11 , wherein an average particle diameter of the first particles in the second anode active material layer is about 50% or less of an average particle diameter of the first particles in the first anode active material layer, and

wherein an average particle diameter of the second particles included in the second anode active material layer is about 50% or less of an average particle diameter of the second particles included in the first anode active material layer.

13. The all-solid secondary battery of claim 1 , wherein the first carbonaceous anode active material is bound to the solid electrolyte layer by at least one of a covalent bond or an ionic bond.

14. The all-solid secondary battery of claim 1 , wherein the first anode active material layer does not comprise an organic material.

15. The all-solid secondary battery of claim 1 , wherein the first carbonaceous anode active material is a sintered product of a carbonaceous precursor, and the carbonaceous precursor is the second carbonaceous anode active material.

16. The all-solid secondary battery of claim 1 , wherein a thickness of the first anode active material layer is about 5% to about 50% of a total thickness of the cathode active material layer, and

wherein the first anode active material layer has a thickness of about 10 nanometers to about 10 micrometers.

17. The all-solid secondary battery of claim 1 , wherein a thickness of the second anode active material layer is about 5% to about 50% of a total thickness of the cathode active material layer, and

wherein the second anode active material layer has a thickness of about 1 micrometer to about 50 micrometers.

18. The all-solid secondary battery of claim 1 , wherein a thickness of the first anode active material layer is less than a thickness of the second anode active material layer.

19. The all-solid secondary battery of claim 1 , wherein at least one of the first anode active material layer or the second anode active material layer further comprises a binder.

20. The all-solid secondary battery of claim 1 , wherein the second anode active material layer comprises the second carbonaceous anode active material and a metal or metalloid anode active material, and the first anode active material layer consists of the first carbonaceous material.

21. The all-solid secondary battery of claim 1 , wherein the second anode active material layer consists of the second carbonaceous material, and the first anode active material layer comprises the first carbonaceous anode active material and a metal or metalloid anode active material.

22. The all-solid secondary battery of claim 1 , wherein the anode current collector, the first anode active material layer, the second anode active material layer, and regions therebetween are Li-free regions which do not comprise lithium in an initial state or a post-discharge state of the all-solid secondary battery.

23. The all-solid secondary battery of claim 1 , wherein the solid electrolyte is an oxide-containing solid electrolyte or a sulfide-containing solid electrolyte.

24. The all-solid secondary battery of claim 23 , wherein the oxide-containing solid electrolyte comprises at least one of Li 1+x+y Al x Ti 2−x Si y P 3−y O 12 wherein 0<x<2 and 0≤y<3, BaTiO 3 , Pb(Zr a Ti 1−a )O 3 wherein 0≤a≤1, Pb 1−x La x Zr 1−y Ti y O 3 wherein 0≤x<1 and 0≤y<1, Pb(Mg 1/3 Nb 2/3 )O 3 —PbTiO 3 , HfO 2 , SrTiO 3 , SnO 2 , CeO 2 , Na 2 O, MgO, NiO, CaO, BaO, ZnO, ZrO 2 , Y 2 O 3 , Al 2 O 3 , TiO 2 , SiO 2 , Li 3 PO 4 , Li x Ti y (PO 4 ) 3 wherein 0<x<2 and 0<y<3, Li x Al y Ti z (PO 4 ) 3 wherein 0<x<2, 0<y<1, and 0<z<3, Li 1+x+y (Al a Ga 1−a ) x (Ti b Ge 1−b ) 2−x Si y P 3−y O 12 wherein 0≤x≤1, 0≤y≤1, 0≤a≤1, and 0≤b≤1, Li x La y TiO 3 wherein 0<x<2 and 0<y<3, Li 2 O, LiOH, Li 2 CO 3 , LiAlO 2 , Li 2 O—Al 2 O 3 —SiO 2 —P 2 O 5 —TiO 2 —GeO 2 , or Li 3+x La 3 M 2 O 12 , wherein M is Te, Nb, or Zr, and 0≤x≤10.

25. The all-solid secondary battery of claim 23 , wherein the oxide-containing solid electrolyte comprises an garnet-type solid electrolyte, and the garnet-type solid electrolyte comprises at least one of Li 7 La 3 Zr 2 O 12 or Li 3+x La 3 Zr 2−a M a O 12 wherein M is at least one of Ga, W, Nb, Ta, or Al, 1≤x≤10, and 0≤a<2.

26. The all-solid secondary battery of claim 23 , wherein the sulfide-containing solid electrolyte comprises at least one of Li 2 S—P 2 S 5 , Li 2 S—P 2 S 5 —LiX wherein X is a halogen, Li 2 S—P 2 S 5 —Li 2 O, Li 2 S—P 2 S 5 —Li 2 O—LiI, Li 2 S—SiS 2 , Li 2 S—SiS 2 —LiI, Li 2 S—SiS 2 —LiBr, Li 2 S—SiS 2 —LiCl, Li 2 S—SiS 2 —B 2 S 3 —LiI, Li 2 S—SiS 2 —P 2 S 5 —LiI, Li 2 S—B 2 S 3 , Li 2 S—P 2 S 5 —Z m S n wherein m and n are each independently a positive number, and Z is Ge, Zn, or Ga, Li 2 S—GeS 2 , Li 2 S—SiS 2 —Li 3 PO 4 , Li 2 S—SiS 2 -Li p MO q wherein p and q are each independently a positive number, and M is P, Si, Ge, B, Al, Ga, or In, Li 7−x PS 6−x Cl x wherein 0≤x≤2, Li 7−x PS 6−x Br x wherein 0≤x≤2, or Li 7−x PS 6−x I x wherein 0≤x≤2.

27. The all-solid secondary battery of claim 23 , wherein the sulfide-containing solid electrolyte comprises an argyrodite-type solid electrolyte, and the argyrodite-type solid electrolyte comprises at least one of Li 7−x PS 6−x Cl x wherein 0≤x≤2, Li 7−x PS 6−x Br x wherein 0≤x≤2, or Li 7−x PS 6−x I x wherein 0≤x≤2.

28. A method of manufacturing an all-solid secondary battery, the method comprising:

providing a solid electrolyte layer;

disposing a first anode active material composition comprising a first carbonaceous anode active material on a first surface of the solid electrolyte layer;

thermally treating the first anode active material composition to form a first anode active material layer;

disposing a second anode active material layer comprising a second carbonaceous anode active material on a surface of the first anode active material layer; and

disposing a cathode active material layer on a second surface of the solid electrolyte layer to manufacture the all-solid secondary battery,

wherein a third anode active material layer is disposed between the anode current collector and the second anode active material layer or between the first anode active material layer and the second anode active material layer,

wherein the third anode active material layer is a metal layer comprising lithium or a lithium alloy;

wherein a first intensity ratio of an intensity of a D band peak to an intensity of a G band peak in a Raman spectrum of the first carbonaceous anode active material is less than a second intensity ratio of an intensity of a D band peak to an intensity of a G band peak in a Raman spectrum of the second carbonaceous anode active material.

29. The method of claim 28 , wherein the thermal treatment is performed at a temperature of about 300° C. to about 900° C. for about 0.1 hour to about 20 hours.

30. The method of claim 28 , further comprising washing the surface of the first anode active material layer with an acidic solution before disposing the second anode active material.