摘要
以Li2SiO3、Mn(CH3COO)2.4H2O和Mg(CH3COO)2.4H2O为原料,采用高温固相反应法成功合成出Li2Mn0.95Mg0.05SiO4锂离子电池正极材料。采用XRD、扫描电镜等技术分析了合成粉末的相组成、结构和微观形貌,利用电池测试仪测试了正极材料的电化学性能。研究结果表明,固相合成的粉末主相为Li2Mn0.95Mg0.05SiO4,同时存在少量的杂质,产物表面形貌、粒度均与未掺杂样品类似,二者均为非球形颗粒,颗粒尺寸约为100～500nm。电化学测试结果表明,Mg掺杂后,正极材料的可逆容量和循环寿命都得到提高。正极材料电化学性能提高的机理在于Mg掺杂稳定了Li2MnSiO4正极材料的结构。
Li2Mn0.95 Mg0.05 SiO4 cathode material for lithium ion batteries was synthesized by traditional solid-atate reaction method used Li2SiO3, Mn（CH3COO）2·4H2O and Mg（CH3COO）2·4H2O as starting materials. XRD and FESEM were used to study the phase, structure and morphology of obtained samples. Electrochemical performance of cathode material was tested. The results show that the main phase of sample prepared via solid-state reaction was LizMn0.95 Mg0.05 SiO4, whereas a small amount of impurities were existed. The particle size of Li2Mn0.95 Mg0.05 SiO4 sample is about 100-500 nm and its particle shape is a quasi-sphere morphology. The experiment results show that the reversible capacity and cycle life of cathode sample was improved through doping Mg, and its mechanism is that doping Mg can stabilize the structure of Li2MnSiO4 cathode material.
出处
《硅酸盐通报》
CAS
CSCD
北大核心
2009年第3期464-467,共4页
Bulletin of the Chinese Ceramic Society
