Li/Li₇La₃Zr₂O₁₂/LiFePO₄ All-Solid-State Battery with Ultrathin Nanoscale Solid Electrolyte

We introduced the nanoconcept in the oxide solid electrolyte Li7La3Zr2O12 (LLZO). All-solid-state Li/LiFePO4 (LFPO) cell using this solid electrolyte with thickness of several micrometers was assembled with appropriate solvent, dispersant, adhesives, and surfactant without cold- or hot-pressing. At room temperature, the Li/LLZO/LFPO cell showed the first discharge capacity of 160.4 mAh g–1, which was 94.4% of the theoretical capacity of LFPO, and the cell provided a discharge capacity of 136.8 mAh g–1 after 100 cycles. At 60 °C, the battery presented more stable electrochemical performance. The capacity loss during cycles 2–100 was only 0.06% (0.7 mAh g–1). The excellent performance could be attributed to the ultrathin solid electrolyte film.