Dead Lithium in Lithium Metal Batteries: Formation, Characterization and Strategies

Lithium (Li) metal anode (LMA) replacing graphite anode for developing Li metal batteries (LMB) with the higher energy density has attracted much attention. However, LMA faces many issues, e. g., Li dendrites, dead Li and the side reactions, which causes the safety hazards and low coulomb efficiency (CE) of battery, therefore, LMB still cannot replace the current Li ion battery for practical use. Among those issues, dead Li is one of the decisive factors affecting the CE of LMB. To better understand dead Li, we summarize the recent work about the generation of dead Li, its impact on batteries performance, and the strategies to reuse and eliminate dead Li. Finally, the prospect of the future LMA and resultant LMB is also put forward.