Unraveling the Operation Mechanisms of Lithium Sulfur Batteries with Ultramicroporous Carbons
Résumé
Quasi-solid-state lithium sulfur batteries (QSS-LSBs) constitute a new type of lithium sulfur batteries having a cathode usually based on ultramicroporous carbon and presenting only one voltage plateau in their discharge profile. As the discharge of QSS-LSBs does not involve polysulfide dissolution, shuttle effects can be suppressed in this system. Here, we report a kinetic model to simulate the discharge process of QSS-LSB based on a two-step reaction mechanism. The simulation results well reproduce the one-plateau discharge profile and reveal that the high Li+ transport resistivity of Li2S and Li2S2 is the key capacity-limiting factor.