‘Spillway’ for electrons could keep lithium metal batteries from catching fire

Science Daily  March 12, 2020
Researchers at UC San Diego have developed a novel separator design for lithium batteries to mitigate the effects of an internal short circuit by limiting the self‐discharge current to prevent cell temperature rise. A nano‐composite Janus separator with a fully electronically insulating side contacting the anode and a partially electronically conductive (PEC) coating with tunable conductivity contacting the cathode is implemented to intercept dendrites, control internal short circuit resistance, and slowly drain cell capacity. They demonstrated that Li‐metal batteries with the Janus separator perform normally before shorting, which then results in a gradual increase of internal self‐discharge over >25 cycles due to PEC‐mitigated shorting. This is contrasted by a sudden voltage drop and complete failure seen with a single layer separator…read more. TECHNICAL ARTICLE