Functional inorganic additives in composite solid-state electrolytes for flexible lithium metal batteries

Flexible lithium metal batteries with high capacity and power density have been regarded as the core power resources of wearable electronics. However, the main challenge lies in the limited electrochemical performance of solid-state polymer electrolytes, which hinders further practical applications. Incorporating functional inorganic additives is an effective approach to improve the performance, including increasing ionic conductivity, achieving dendrite inhibiting capability, and improving safety and stability. Herein, this review summarizes the latest developments of functional inorganic additives in composite solid-state electrolytes for flexible metal batteries with special emphasis on their mechanisms, strategies, and cutting-edge applications, in particular, the relationship between them is discussed in detail. Finally, the perspective on future research directions and the key challenges on this topic are outlooked.