摘要
以氢氧化锂、柠檬酸以及醋酸锰、醋酸镁为原料,利用低温固相法制备了LiMn2O4及其Mg元素的掺杂产物,采用XRD、FTIR和恒流充放电测试研究了合成产物的性能。XRD测试表明,所有产物均为尖晶石相结构,Mg离子能很好地溶入尖晶石相产物的晶格之中;FTIR结果显示,经过Mg元素掺杂改性后,产物中的Mn(Ⅳ)-O和Mn(Ⅲ)-O键分别存在着蓝移和红移现象;电化学测试则表明,LiMg0.2Mn1.8O4的初始电化学容量较LiMn2O4低,但经过一定的循环次数后,电化学容量超过了LiMn2O4,且在整个循环过程中LiMg0.2Mn1.8O4的容量衰减率较小,循环性能相对于未掺杂前的产物得到了较大的提高。
The positive materials LiMn2O4 and LiMg0.2Mn1.8O4 were H2O, Mn (CH3COO)2·4H2O, Mg (CH3COO)2·4H2O by solid phrase synthesized with LiOH. H20, C6I-Is07- method in low temperature. And their performance was tested by XRD, FTIR and costant-current charging/discharging methods. The test results showed that, Mg^2+ was adulterated in the spinel crystal lattice, and caused different effects on the structure and FTIR charater of spinel LiMn2O4. Initial capacity of LiMg0.2Mn1.8O4 decreased in some degree, but both cyclic performance and electrochemical capacity after cycling improved a lot.
出处
《电池工业》
CAS
2008年第1期40-43,共4页
Chinese Battery Industry