Electrochemical stability of lithium halide electrolyte with antiperovskite crystal structure.

The present study is focused on a relatively new class of solid-state lithium halide electrolytes with antiperovskite crystal structure that are designed to alleviate safety concerns related to conventional lithium-ion batteries. The solid-state Li 3 ClO electrolyte membranes were produced by a casting/delamination method and deposited on a graphite-based working electrode. The electrolyte charge transfer resistances, electrochemical performance, and chemical stability in a half-cell configuration were evaluated over a broad temperature range from room temperature up to 100 °C. The electrochemical cells with lithium metal as a reference electrode demonstrated linear Arrhenius behavior in the temperature range of 25–100 °C confirming the absence of phase transformations. Cyclic voltammetry at 50 °C and 100 °C confirms that the electrochemical cell performance during lithiation/delithiation from 0.05 to 1.00 V is reproducible within at least 100 cycles. The solid-state electrolyte electrochemical stability in contact with lithium metal is confirmed for the first time by demonstrating the constant values of charge transfer resistances during charge/discharge operations in 575 cycles at 50 °C and 1/5 C -rate. Transport of lithium ions between the lithium metal and Li 3 ClO electrolyte in contact with a graphite working electrode provides evidence that lithium halide antiperovskites can serve as effective and electrochemically stable electrolytes for a new generation of all-solid-state lithium-ion or lithium metal batteries. Image 1031 • A solid-state electrolyte with antiperovskite structure was tested in a half-cell vs. lithium anode. • Electrolyte chemical stability in presence of Li-metal at 50 °C is confirmed by AC impedance. • Continuous cycling within 6 months at 50 and 100 °C demonstrate >80% specific capacity retention. [ABSTRACT FROM AUTHOR]