All-solid-state rechargeable lithium batteries using SnX-P2X5 (X = S and O) amorphous negative electrodes

SnS-P₂S₅ and SnO-P₂O₅ amorphous materials were prepared by a mechanical milling technique. The SnO-P₂O₅ milled materials worked as a reversible electrode with higher capacity than SnO crystal in rechargeable lithium cells with conventional liquid electrolytes. All-solid-state cells with a SnX-P₂X₅ (X = S and O) amorphous electrode and the Li₂S-P₂S₅ glass-ceramic electrolyte were charged and discharged at room temperature. The sulfide electrodes exhibited better charge-discharge performance than the oxide electrodes, suggesting that SnS-P₂S₅ electrodes are more compatible with Li₂S-P₂S₅ sulfide solid electrolytes. All-solid state batteries 80SnS·20P₂S₅/LiCoO₂ showed a charge-discharge plateau of about 3.4 V and high reversible capacity of over 400 mAh/g, even after 50 cycles. The SnX (X = S and O)-based amorphous materials are promising negative electrode materials with high capacity for rechargeable lithium batteries using not only liquid electrolytes but solid electrolytes.