Li_3V_2(PO_4)_3/C材料合成中碳源含量优化  

The optimized content of the carbon source in synthesis of Li_3V_2(PO_4)_3/C

作　　者：徐艳辉[1] 范富强[1] 吴群[1] 韩丽娟[1] 孙丰霞[1] 孟良荣[1] 

机构地区：[1]苏州大学化学电源研究所,江苏苏州215006

出　　处：《电池工业》2013年第1期11-13,共3页Chinese Battery Industry

基　　金：江苏省六大人才高峰项目;江苏省自然科学基金项目(BK2009110)

摘　　要：通过固相法和溶胶-凝胶法合成不同碳含量的磷酸钒锂/C正极材料,研究了作为碳源的蔗糖和柠檬酸添加量对产物电化学性能的影响。实验发现,在固相合成方法中,添加量高于10.5%(质量百分数)时进一步增加蔗糖添加量后产物放电容量变化不明显。但是在溶胶-凝胶合成方法中,柠檬酸的添加量存在最佳值,高于或者低于此最佳数值都会引起产物容量的降低,这是与固相合成技术的一个明显不同之处。另一点不同之处在于对于溶胶-凝胶合成的样品,最佳添加量与产物的工作电流有关。本实验条件下,在0.2C倍率以下柠檬酸与氢氧化锂最佳比值为1∶3,但是在放电倍率高于0.5C时最佳比值为1∶2。The Li3V2 （PO4）3 with different contents of carbon positive electrode materials have been synthesized via solid-state method and sol-gel one. The effect of sucrose and citric acid as carbon sources on the electrochemical properties has been investigated. It was found that in the solid-state synthesis method when the content of the sucrose is more than 10.5wt. %, the further increase in the sucrose content can not increase the electrode properties. For the sol-gel synthesis technology, there exists an optimum content of citric acid. In addition, or the sol-gel synthesis technology, the optimum content depends on the operation mode, i. e. , working current density. The ratio of carbon source vs. Li source in the precursor has been also studied. In our experimen- tal condition, in lower rate than 0.2C, the optimum ration of citric acid vs. LiOH is 1 ~ 3, but in higher rate than 0.5C, the optimum ratio is 1 ： 2.

关 键 词：磷酸钒锂 锂离子电池 电化学性能 

分 类 号：TM912.9[电气工程—电力电子与电力传动]