Disclosed is a method of fabricating a battery or battery component having a solid state electrolyte. A scaffold is provided, the scaffold comprising: a dense central layer comprising a dense electrolyte material, the dense central layer having a first surface, and a second surface opposite the first surface; a first porous layer comprising a first porous electrolyte material, the first porous layer disposed on the first surface of the dense central layer, the porous electrolyte material having a first network of pores therein; wherein each of the dense electrolyte material and the first porous electrolyte material are independently selected from garnet materials. Carbon is infiltrated into the first porous layer. Sulfur is also infiltrated into the first porous layer. The battery component may be used in a variety of battery configurations.