固态金属锂电池研究进展:外部压力和内部应力的影响

The solid-state lithium metal battery has the advantages of high theoretical energy density and high safety, and is a very promising next-generation energy storage system. However, the limited solid-solid contact retards the migration of Li ions between solid electrolytes and electrodes. Consequently, applying external pressure is an effective route to enhance interfacial contacts and extend battery cycle life. At the same time, the internal stresses generated with the volume changes of electrodes during cycling will also hugely influence the interfacial contacts. In this paper, the mechanisms of external pressure and internal stresses on electrodes and electrolytes are reviewed by introducing two basic physical contact models and analyzing the physical properties of sulfide, oxide, polymer electrolytes and lithium metal anodes. Finally, the roles of external pressure and internal stresses in all-solid-state Li metal batteries are summarized and prospected.