ALL SOLID-STATE SODIUM-SULFUR OR LITHIUM-SULFUR BATTERY PREPARED USING CAST-ANNEALING METHOD

The present invention is directed to solid-state composite cathodes that comprise NaS or LiS, NaPS, or Li3PS4, and mesoporous carbon. The present invention is also directed to methods of making the solid-state composite cathodes and methods of using the solid-state composite cathodes in batteries and other electrochemical technologies.