pH 对水溶液锂离子电池负极材料 LiV3O8性能的影响

摘要

采用柠檬酸溶胶-凝胶法合成了层状锂离子嵌入化合物LiV3 O8，用XRD、 SEM对其晶体结构和表面形貌进行表征，用循环伏安法对其嵌锂性能和扩散系数进行测定，用恒电流充放电法研究了电解液pH对电极可逆性及对模拟电池容量和循环性能的影响。结果显示，电解液pH ＝7时，电池的性能最优，首次放电比容量为81.0 mAh · g-1，40次后比容量保持率达89.1％。%Layered lithium ion intercalation compound LiV 3 O8 was synthesized by citric acid sol -gel method.The crystal structure and surface morphology were characterized by XRD and SEM.The lithium intercalation properties and the diffusion coefficients of as prepared materials were tested by cyclic voltammetry.The effect of pH on the reversibility of electrode , battery capacity and cycle performance were studied by galvanostatic charge -discharge.The battery showed the best electrochemical performance with electrolyte pH =7.The first specific discharge capacity was 81 mAh· g-1 with a retention of 89.1%after 40 cycles.