Clean Technica article referencing the NASA research and info from NASA itself. The more technical information is probably available if I dug enough, but this does sound like a positive development.

NASA has revealed a powerful new battery that could change the future of flight. Their solid-state sulfur selenium battery is designed to replace gas-powered engines with electric ones. This leap in ...

PITTSBURGH, April 28, 2021 (GLOBE NEWSWIRE) -- II‐VI Incorporated (Nasdaq: IIVI), a leader in engineered materials, today announced that it will introduce its lithium-sulfur/selenium cathode ...