Sulfide Glass‐Ceramic Electrolytes for All‐Solid‐State Lithium and Sodium Batteries

TLDR

Sulfide glass‑ceramic electrolytes that conduct Li⁺ or Na⁺ have been developed over the last decade, and because high‑temperature phases are difficult to synthesize by conventional solid‑state reaction, glass electrolytes serve as important precursors for forming these phases. High‑temperature phases of Li₇P₃S₁₁ and cubic Na₃PS₄ are precipitated from mother glasses, yielding glass‑ceramics with higher conductivity, and these glass‑ceramics are used to fabricate all‑solid‑state batteries by cold‑pressing at room temperature. The sulfide glass‑ceramic electrolytes achieve 25‑°C conductivities of 1.1 × 10⁻² S cm⁻¹ for Li₇P₃S₁₁ and 7.4 × 10⁻⁴ S cm⁻¹ for Na₃.₀₆P₀.₉₄Si₀.₀₆S₄, exhibit favorable mechanical properties enabling solid–solid contacts by cold‑pressing without heat, and enable all‑solid‑state Li‑In/S and Na‑Sn/TiS₂ cells that operate as secondary batteries with good room‑temperature cycle performance.

Abstract

Sulfide glass‐ceramic electrolytes with L i + or N a + ion conduction have been developed in last decade. High‐temperature phases of L i 7 P 3 S 11 and cubic N a 3 PS 4 are precipitated from mother glasses, and the obtained glass‐ceramics show higher conductivity than the mother glasses. It is difficult to synthesize those high‐temperature phases by conventional solid‐state reaction, and glass electrolytes are thus important as a precursor for forming high‐temperature phases. The highest conductivities at 25°C of 1.1 × 10 −2 S/cm for Li + ion conductor ( L i 7 P 3 S 11 ) and 7.4 × 10 −4 S/cm for Na + ion conductor ( N a 3.06 P 0.94 S i 0.06 S 4 ) are achieved in sulfide glass‐ceramic electrolytes. All‐solid‐state batteries with sulfide glass‐ceramic electrolytes were fabricated by cold press at room temperature. Sulfide electrolytes have favorable mechanical properties to form favorable solid–solid contacts in solid‐state batteries by pressing without heat treatment. All‐solid‐state L i‐ I n/ S and N a‐ S n/ T i S 2 cells using sulfide glass‐ceramic electrolytes operate as secondary batteries and exhibit good cycle performance at room temperature.