Cerium-alloyed dendrite-inhibited highly stable anodes for all-solid-state lithium batteries

All-solid-state lithium (Li) batteries (ASSLBs) can inhibit the growth of Li dendrites to some extent, whereas Li dendrites are still unavoidable, which decreases the electrochemical performance of ASSLBs. Among the many methods developed for suppressing Li dendrites, the use of Li-In alloy anodes is a common strategy due to its smooth voltage plateau and stable electrochemical performance. However, Li-In dendrites still appear in Li-In anode-based ASSLBs. Herein, a rare earth (RE) element (Ce) was introduced to form Li-In-Ce alloy anodes, which contain micro-sized CeIn₃ particles in a Li-In substrate. Compared with Li-In, the Ce-containing Li-In-Ce anode had better electrochemical properties and greater cycling stability (>10 times, ∼750 cycles) in the ASSLB. The CeIn₃ particles in the Li-In-Ce alloys can limit the deformation of Li-In and promote the even plating of Li, significantly suppressing the growth of Li-In dendrites, which is observed <i>in situ via</i> special solid cells. In addition, this improvement strategy for Li-In alloys is universal for other RE elements (such as Y, La, Pr, Sm, or Yb), and the electrochemical properties can be influenced by the metal bond strength of RE-In in REIn₃. This work can guide the design of high-performance anodes in ASSLBs.