Constructing an interface compatible Li anode in organic electrolyte for solid-state lithium batteries

Abstract To obtain high energy solid-state lithium batteries (SSLB), matching solid electrolyte with lithium metal remains a challenge due to the lack of stable contact on the solid electrolyte/lithium interfaces. Herein, a lithium metal anode modified by solid state electrolyte interphase (SEI) was prepared to assemble SSLB. XPS results show the components of SEI layer contain LiCO3, LiF and ROCO2Li, which play a role in stabilizing the interface. At a current density of 0.1 mA cm−2, the Li (M)/Li10GeP2S12 (LGPS)/Li (M) symmetric cell has cycled with a small polarization for 500 h. And the Cyclic voltammetry of Li (M)/LGPS/Au also proves the interface stability. The coin cells assembled with SEI modified Li anode, LGPS, and LiNi0.8Co0.15Al0.05O2 (NCA) cathode show a large initial discharge capacity of 117.6 mAh g−1 and good cycle performance, capacity retention of 77.6% after 100th cycles. The SEI layer formed in the organic electrolyte is applied to SSLB, providing the possibility for the combined development of organic and solid state batteries.