As a battery component, sulfur – low-cost, abundant and with a high theoretical specific capacity – seems tailor-made for practical, affordable solid-state batteries for EVs and other uses. But so far, that theoretical capacity has stayed theoretical. By finding the perfect particle size for solid-state electrolyte powder and changing the fabrication strategy, a team led by University of Chicago Pritzker School of Molecular Engineering Prof. Shirley Meng created a sulfur-based composite cathode that delivers a discharge specific capacity of about 1500 milliampere-hours (mAh) per gram of sulfur. This puts science closer than ever to tapping sulfur’s theoretical capacity of 1675 mAh per gram. Furthermore, the team successfully demonstrated this performance in a practical pouch cell format, proving the technology's scalability and potential for real-world EV applications.