Solid-State Lithium-Metal Batteries Based on Antiperovskite Superionic Conductors

摘要

The present study is focused on a relatively new class of solid-state superionic electrolytes with antiperovskite crystal structure. The solid-state electrolyte layers were produced by casting/delamination and deposited on a graphite-based Cu-supported 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 23-100°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 1.0V is reproducible within at least 100 cycles. The solid-state electrolyte electrochemical stability in contact with lithium metal was confirmed by the absence of specific capacity losses during charge/discharge operations (320 cycles at 50°C and 1/5 C-rate) and the observed decrease in charge transfer resistances. Transport of lithium ions between the lithium metal and solid electrolyte in contact with a graphite working electrode provides evidence that antiperovskites can serve as effective and electrochemicalh/ stable electrolytes for a new generation of all-solid-state lithium-ion or lithium metal batteries.