Solid-state lithium batteries-from fundamental research to industrial progress

In recent years, solid-state lithium batteries (SSLBs) using solid electrolytes (SEs) have been widely recognized as the key next-generation energy storage technology due to its high safety, high energy density, long cycle life, good rate performance and wide operating temperature range. However, SSLBs still suffer from many obstacles that hinder their practical application. This review discusses typical lithium-ion conductors and their in-depth lithium-ion conduction mechanism. The key interfacial problems of electrolytes and electrodes for SSLBs are comprehensively elaborated and several possible solution methods are proposed. Furthermore, three viable manufacturing strategies for free-standing thin SE membranes are discussed in details. Moreover, for the first time, the government policies and latest company industrialization process relative to SSLBs worldwide are systematically summarized. Finally, several potential strategies are identified for the future development of high-energy-density SSLBs.