三价离子取代NASICON型固体电解质的制备及其性能

Preparation and performance of NASICON-type solid electrolyte substituted by trivalent ion

采用磷酸溶液法制备了Li1.3Y0.3Ti1.7 (PO4)3 (LYTP)、Li1.3La0.3Ti1.7 (PO4)3 (LLaTP)、Li1.3In0.3Ti1.7 (PO4)3 (LInTP)三种NASICON型固体电解质。讨论了粉末烧结温度、电解质片烧结温度对电解质电导率的影响,结果表明:当电解质粉末的烧结温度为800 ℃、电解质片的烧结温度为900 ℃时,所制备电解质的电导率最大,电导率分别为1.85×10^-4、1.82×10^-4、1.27×10^-4 S/cm。以制得的LYTP 电解质片为电解质,LiFePO4为正极,组装了固态电池,电池在60 ℃充放电时,1C 下循环100圈的容量保持率为85%。

Three kinds of NASICON-type solid electrolyte, Li1.3Y0.3Ti1.7 (PO4)3 (LYTP), Li1.3La0.3Ti1.7 (PO4)3 (LLaTP) and Li1.3In0.3Ti1.7(PO4)3 (LInTP) were prepared through phosphate solution method. This paper mainly research on the effects of sintering temperature of electrolyte powders and pellets on ionic conductivity. The results showed that the optimal sintering temperature of electrolyte powders and pellets is 800 ℃and 900 ℃, respectively, and the maximum ionic conductivity of LYTP, LLaTP and LInTP is 1.85×10^-4, 1.82×10^-4 and 1.27×10^-4 S cm^-1. The electrochemical performance of solid-state battery with as-prepared LYTP electrolyte pellet was studied. The discharge capacity retention of solid-state battery with LYTP electrolyte can reach 85% after cycling 100 times at 60 ℃ with current density of 1 C.