Abstract: The electrochemical behavior of lithium incorporation into aluminum electrode in LiTFSI/NaTf molten salt electrolyte was studied with electrochemical techniques，including cyclic voltammetry，chronopotentiometry and chronoamperometry.The reduction reaction was found to involve a nucleation process at the aluminum electrode，and only one LiAl alloy phase was reversible.The galvanostatic cycle experiments showed that the coulombic efficiency was very low in the first cycle and decreased with increasing current density，and increased with increasing operating temperature.The results of chronoamperometry indicated that the incorporation of lithium into aluminum for the formation of α-phase Li-Al alloy was limited by its rate of diffusion，with a measured diffusion coefficient of 1.7×10^-10 cm²·s^-1.

Key words: high temperature, molten salt, aluminum electrode, electrochemical behavior, nucleation process

摘要： 采用循环伏安、计时电流和恒电流充放电等电化学测试技术考察了LiTFSI/NaTf熔盐电解质中锂在铝电极上的电化学行为。研究结果表明：在该熔盐中，锂在铝电极上的电化学还原过程伴随着锂铝合金的成核过程，且反应生成的LiAl合金只有一种合金相是可逆的；恒电流循环充放电实验发现，首次循环的库仑效率较低，库仑效率随电流密度的增大而有所减小，但随温度的升高而增大。计时电流实验发现，锂原子嵌入铝电极中形成α-LiAl合金的过程受锂在铝基体内扩散步骤控制，且该扩散系数为1.7×10^-10 cm²·s^-1。

关键词: 高温, 熔盐, 铝电极, 电化学行为, 成核过程