SOLID-STATE BATTERY

Disclosed is a solid-state battery which includes a positive electrode, a negative electrode and a solid electrolyte membrane interposed between the positive electrode and the negative electrode, wherein the solid electrolyte membrane includes a first solid electrolyte layer and a second solid electrolyte layer, the first solid electrolyte layer faces the positive electrode, the first solid electrolyte layer includes a first sulfide-based solid electrolyte, the second solid electrolyte layer includes a second sulfide-based solid electrolyte, and the second sulfide-based solid electrolyte has an average particle diameter (D50) larger than the average particle diameter (D50) of the first sulfide-based solid electrolyte. In the solid-state battery, it is possible to control the lithium-ion plating rate on a lithium metal negative electrode uniformly so that lithium-ion may be plated uniformly, and thus to reduce dendrite formation.