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

We introduced the nanoconcept in the oxide solid electrolyte Li 7 La 3 Zr 2 O 12 (LLZO). All-solid-state Li/LiFePO 4 (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.