Probing pressure-Induced Structural and Conductivity Changes in Li6.5La3Nb0.5Zr1.5O12 (c-LLZO) Garnet Electrolytes

The garnet-type solid electrolyte Li6.5La3Nb0.5Zr1.5O12 (c-LLZO) is widely regarded as one of the most promising candidate SICs due to its high ionic conductivity (~10^-3 S/cm) and low electronic conductivity (σe < 10-8 S/cm) at room temperature, good mechanical strength and electrochemical stability. While temperature effects on c-LLZO’s ionic transport have been extensively studied, the role of pressure as a thermodynamic parameter has been explored less. This study aims to elucidate the effect of pressure on Li-ion transport mechanisms using high-pressure neutron diffraction. In combination with existing studies of electrochemical impedance spectroscopy (EIS) and Raman spectroscopy, our investigation will probe correlations between pressure-induced structural changes and ionic conductivity, providing insights crucial to optimizing c-LLZO-based solid electrolytes for enhanced battery performance.

石榴石型固体电解质Li₆.₅La₃Nb₀.₅Zr₁.₅O₁₂（c-LLZO）因室温下具备约10^-3 S/cm的高离子电导率、σe < 10^-8 S/cm的极低电子电导率，以及优异的机械强度与电化学稳定性，被广泛认为是最具潜力的固体离子导体（SICs）候选材料之一。尽管学界已针对c-LLZO的离子输运过程开展了大量温度效应相关研究，但作为热力学参数的压力所发挥的作用却鲜有探讨。本研究拟借助高压中子衍射技术，阐明压力对锂离子输运机制的调控作用。结合现有电化学阻抗谱（EIS）与拉曼光谱（Raman spectroscopy）的研究成果，本研究将探究压力诱导的结构变化与离子电导率之间的内在关联，为优化基于c-LLZO的固体电解质以提升电池性能提供关键理论支撑。