Rapid Preparation of Li2S-P2S5 Solid Electrolyte and Its Application for Graphite/Li2S All-Solid-State Lithium Secondary Battery

70Li 2 S · 30P 2 S 5 (mol%) solid electrolytes (SE) were prepared with much shorter time (within several hours) by applying higher mechanical stress using a pulverizer. The obtained SE (MM sample) showed rather development of the crystalline Li 7 P 3 S 11 as compared with the glass SE, resulting in the conductivity value between the crystalline and glass SE. By applying to the graphite/Li 2 S all-solid-state cells, improved energy density, as compared with that of the In/Li 2 S cells, was achieved. The rate capability of the graphite/Li 2 S cells was dependent on the conductivity of the SE. The present milling process using a pulverizer is advantageous for producing the SE being applicable for all-solid-state battery production.