AUTHOR=Wang Shuo , Wu Xinbin , Liang Yuhan , Xu Yushuai , Guan Shundong , Wen Kaihua , Miao Xiang , Liang Ying , He Hongcai , Lin Yuanhua , Shen Yang , Nan Ce-Wen TITLE=Facile synthesis of lithium argyrodite Li5.5PS4.5Br1.5 with high ionic conductivity for all-solid-state batteries JOURNAL=Frontiers in Chemical Engineering VOLUME=Volume 4 - 2022 YEAR=2022 URL=https://www.frontiersin.org/journals/chemical-engineering/articles/10.3389/fceng.2022.883502 DOI=10.3389/fceng.2022.883502 ISSN=2673-2718 ABSTRACT=Bromine-rich lithium argyrodite electrolytes with high ionic conductivity and low cost merit are promising for replacing the flammable liquid electrolytes and separators in lithium-ion batteries. However, the synthesis process of the argyrodite electrolytes is usually complex and time-consuming. Herein, we use a facile solid-state reaction method to obtain a highly Li-ion conductive Li5.5PS4.5Br1.5 (LPSB). The influence of annealing temperature on the phase and ionic conductivity of the LPSB is investigated for the first time. A high ionic conductivity of 5.21×10-3 S cm-1 at room temperature for the LPSB with minor LiBr impurity is achieved by directly annealing at 430C for 8 h. The In/InLi | LPSB | LiCoO2@ LiNb0.5Ta0.5O3 (LCO(coated))-LPSB cell with 8.53 mg cm-2 LCO loading shows a discharge capacity of 102 mAh g-1 with a high capacity retention of 93% after 70 cycles at 0.5 mA cm-2 at 30°C.