By using highly Li-ion conductive 78Li2S-22P2S5 glass-ceramic (7822gc) as both the electrolyte and active material in the composite cathode obtained via ball-milling the 7822gc with multiple carbons, a kind of monolithic all-solid-state batteries were prepared with a lithium-indium foil as the anode. Such 7822gc-based monolithic batteries present stable discharge capacity of 480.3 mA h g-1 at 0.176 mA cm-2 after 60 cycles, which is three times larger than that of the previous work, with the highest capacity obtained so far among all attempts of using sulfide electrolytes as the active materials. High capacity retention of 90.6% and Coulombic efficiency of higher than 99% with high active material loading of 7 mg cm-2 were also obtained. X-ray photoelectron spectroscopy was used to reveal the electrochemical reaction mechanisms in the 7822gc cathode.
Keywords: 78Li2S−22P2S5; all-solid-state battery; glass−ceramic; lithium ion battery; solid electrolyte.