Achieving Stable Lithium Metal Anode at 50 mA cm-2 Current Density by LiCl Enriched SEI

Lithium metal batteries are intensively studied due to the potential to bring up breakthroughs in high energy density devices. However, the inevitable growth of dendrites will cause the rapid failure of battery especially under high current density. Herein, the utilization of tetrachloroethylene (C2Cl4) is reported as the electrolyte additive to induce the formation of the LiCl-rich solid electrolyte interphase (SEI). Because of the lower Li ion diffusion barrier of LiCl, such SEI layer can supply sufficient pathway for rapid Li ion transport, alleviate the concentration polarization at the interface and inhibit the growth of Li dendrites. Meanwhile, the C2Cl4 can be continuously replenished during the cycle to ensure the stability of the SEI layer. With the aid of C2Cl4-based electrolyte, the Li metal electrodes can maintain stable for >300 h under high current density of 50 mA cm(-2) with areal capacity of 5 mAh cm(-2), broadening the compatibility of lithium metal anode toward practical application scenarios.

Automated summary

Researchers reported the use of tetrachloroethylene (C2Cl4) as an electrolyte additive in lithium metal batteries to induce the formation of a LiCl-rich solid electrolyte interphase (SEI), which inhibits the growth of lithium dendrites, improves stability, and extends the lifespan of Li metal electrodes.