Interface effects on self-forming rechargeable Li/I₂-based solid state batteries

Solid state batteries are an emerging alternative to traditional liquid electrolyte cells that provide potential for safe and high-energy density power sources. This report describes a self-forming, solid state battery based on the Li/I2 couple using an LiI-rich LiI(3-hydroxypropionitrile)2 electrolyte (LiI-LiI(HPN)2). As the negative and positive active materials are generated in situ, the solid electrolyte-current collector interfaces play a critical role in determining the electrochemical response of the battery. Herein, we report the investigation of solid electrolyte-current collector interfaces with a self-forming LiI-LiI(HPN)2 solid electrolyte and the role of varying interface design in reducing resistance during cycling.