Solid-State Lithium Sulfur Batteries Operated at 37 degrees C with Composites of Nanostructured Li7La3Zr2O12/Carbon Foam and Polymer

An all solid-state lithium-ion battery with high energy density and high safety is a promising solution for a next-generation energy storage system. High interface resistance of the electrodes and poor ion conductivity of solid-state electrolytes are two main challenges for solid-state batteries, which require operation at elevated temperatures of 60–90 ??C. Herein, we report the facile synthesis of Al3+/Nb5+ codoped cubic Li7La3Zr2O12 (LLZO) nanoparticles and LLZO nanoparticle-decorated porous carbon foam (LLZO@C) by the one-step Pechini sol–gel method. The LLZO nanoparticle-filled poly(ethylene oxide) electrolyte shows improved conductivity compared with filler-free samples. The sulfur composite cathode based on LLZO@C can deliver an attractive specific capacity of >900 mAh g–1 at the human body temperature 37 ??C and a high capacity of 1210 and 1556 mAh g–1 at 50 and 70 ??C, respectively. In addition, the solid-state Li–S batteries exhibit high Coulombic efficiency and show remarkably stable cycling performance