Electrochemical Performance of a PVDF-HFP-LiClO-LiLaZrTaO Composite Solid Electrolyte at Different Temperatures.

The stability and wide temperature performance range of solid electrolytes are the keys to the development of high-energy density all-solid-state lithium-ion batteries. In this work, a PVDF-HFP-LiClO-LiLaZrTaO (LLZTO) composite solid electrolyte was prepared using the solution pouring method. The PVDF-HFP-LiClO-LLZTO composite solid electrolyte shows excellent electrochemical performance in the temperature range of 30 to 60 °C. By assembling this electrolyte into the battery, the LiFePO/PVDF-HFP-LiClO-LLZTO/Li battery shows outstanding electrochemical performance in the temperature range of 30 to 60 °C. The ionic conductivity of the composite electrolyte membrane at 30 °C and 60 °C is 5.5 × 10 S cm and 1.0 × 10 S cm, respectively. At a current density of 0.2 C, the LiFePO/PVDF-HFP-LiClO-LLZTO/Li battery shows a high initial specific discharge capacity of 133.3 and 167.2 mAh g at 30 °C and 60 °C, respectively. After 50 cycles, the reversible electrochemical capacity of the battery is 121.5 and 154.6 mAh g at 30 °C and 60 °C; the corresponding capacity retention rates are 91.2% and 92.5%, respectively. Therefore, this work provides an effective strategy for the design and preparation of solid-state lithium-ion batteries.