New insights into “dead lithium” during stripping in lithium metal batteries

Lithium (Li) metal attributes to the promising anode but endures the low Columbic efficiency (CE) and safety issues from the inactive Li accumulation. The metallic Li which is isolated from the lithium anode (named dead Li⁰) consists the major component of the inactive Li. We systematically and meticulously investigated the formation and evaluation of dead Li⁰ during stripping process from electron transfer, the oxidation of Li⁰ to Li⁺ and the diffusion of Li⁺ through solid electrolyte interphase (SEI). The above-mentioned processes were regulated by adjusting the contact sites of electron channels, the dynamic rate of conversion from Li⁰ to Li⁺, and the structure as well as components of SEI. The design principles for achieving less dead Li⁰ and higher CE are proposed as a proof of concept in lithium metal batteries. This new insight sheds a comprehensive light on dead Li⁰ formation and guides the next-generation safe batteries for future application.