Lithium-sulfur (selenium) batteries are appealing choices for realizing the next-generation electrochemical storage systems with high energy. However, traditional liquid-electrolyte-based batteries suffer irreversible loss of soluble intermediates from the cathode, and hazardous dendrite formation and buildup of insulative species at the anode. Here we propose to construct solidified electrode/electrolyte interfaces that effectively suppress the intermediate crossover from the cathode and the dendrite evolution at the anode. Our strategy is realized through a facile in situ interfacial polymerization process, during which a liquid/polymer-gel hybrid electrolyte is formed between two electrodes. The electrolyte consists of a thin gradient solidification layer extended from the surface to the bulk of the cathode, so that liquid electrolyte is preserved inside the cathode to ensure rapid Li+ transport and high utilization of active materials. The solidified electrolyte also shows improved mechanical strength and favorable chemical compatibility with Li metal, which helps to effectively inhibits the dendrite growth and unfavorable side reactions at the anode/electrolyte interface. With the new electrolyte configuration, the Li-S (Se) cells have simultaneously demonstrated high capacity, stable cycling (over 500 discharge-charge cycles without LiNO3) and favorable rate capability. Further, with the electrolyte, we are able to build a high-performance laminated Li-S pouch cell to demonstrate the practical deployment of the strategy at an industrial level.

Stabilizing the electrochemistry of lithium-sulfur (Selenium) battery via solidified electrode/electrolyte interface

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.