Achieving high capacity of Li−rich Mn−based cathode materials in all−solid−state batteries: Issues and opportunities

High energy density all−solid−state batteries (ASSBs) have been regarded as the most promising next generation electrochemical energy storage systems. With lithium metal selected as an ideal anode, searching for suitable cathode materials remains a tough task. Recent studies reveal that Li−rich Mn−based cathode (LRM) can deliver a higher reversible capacity compared to its counterpart in ASSBs. However, corresponding research of LRM ASSBs (LRASSBs) is still in the infant stage and some critical issues remain to be solved, such as the poor kinetics, complex and serious interfacial reactions, and unsatisfactory cyclability. Herein, a focused review is proposed, bringing in−depth understandings on the mechanisms of capacity issues of LRASSBs caused by the kinetic and interfacial problems. In addition, potential modification strategies on fully releasing the capacity superiority of LRM are proposed in various scales. Furthermore, perspectives for designing high−energy−density LRASSBs are systematically analyzed.