不同合成工艺对LiMn_2O_4电化学性能的影响  

Effect of different synthesis processes on properties of LiMn_2O_4

作　　者：夏继平[1] 叶学海[1] 张晓波[1] 付春明[1] 于晓微[1] 

机构地区：[1]中海油天津化工研究设计院,天津300131

出　　处：《电源技术》2013年第11期1929-1931,共3页Chinese Journal of Power Sources

摘　　要：以乙酸锂(CH3COOLi)和乙酸锰[Mn(CH3COO)2]为原料,通过高温固相法和喷雾干燥法分别合成了LiMn2O4。用XRD、SEM、恒流充放电测试和交流阻抗谱(EIS)方法,研究了不同合成工艺对正极材料LiMn2O4的结构、形貌及电化学性能的影响。研究结果表明:用喷雾干燥法合成的正极材料,在0.1 C(1 C=148 mAh/g)的充放电倍率下,首次放电比容量高达118.1 mAh/g,经50循环次后,容量保持率为96.7%;在1 C的充放电倍率下,在常温和55℃下的首次放电比容量分别为115.9和117.9 mAh/g,经过50次充放电循环后,容量保持率分别为95.9%和97.8%;电化学交流阻抗表明,用喷雾干燥法合成的正极材料的阻抗Rct小于用高温固相法合成的材料。LiMn204 cathode materials were synthesized by high temperature solid and spray drying method, using CH3COOLi and Mn （CH3COO）2. The structure, morphology and electrochemical properties of LiMn204 cathode materials were analyzed by XRD, SEM, galvanostatic charge-discharge test and AC impedance methods. The results show that the LiMn204 cathode materials synthesized by spray drying method exhibits an initial discharge capacity of 118.1 mAh/g at 0.1 C （1 C=148 mAh/g） rate, 96.7% of initial capacity is preserved after 50 cycles. An initial discharge capacity are 115.9mAh/g and 117.9mAh/g at 1 C （1 C=148 mAh/g） rate at both RT and 55 C respectively, and 95.9% and 97.8% of initial capacity are preserved after 50 cycles. Electrochemical impedance spectroscopy shows that impedance R of LiMn204 cathode materials synthesized by spray drying method is less than by high temperature solid method.

关 键 词：锂离子电池 LIMN2O4 高温固相法 喷雾干燥法 

分 类 号：TM912.9[电气工程—电力电子与电力传动]