摘要
以柠檬酸为螯合剂和碳源,采用溶胶凝胶法在强弱不同条件下制备锂离子正极材料Li3V2(PO4)3/C。利用XRD、SEM和恒电流充放电等进行测试和表征。结果表明,所有样品为纯相的单斜Li3V2(PO4)3,制备条件的不同不会影响Li3V2(PO4)3正极材料的晶型结构和晶胞参数,但对材料颗粒尺寸有较大影响,加入蔗糖可以抑制颗粒的长大和团聚,从而影响电化学性能;在3.0～4.3 V电压,由于Li3V2(PO4)3结构的稳定性,在低倍率下表现出优异的循环性能;随着颗粒的变大和团聚,材料的倍率性变差,在高倍率下充放电容量衰减快。
Li3V：（PO4）dC was synthesizedby sol-gel method taking citric acid as chelate and C sources at different preparation conditions. The effects of preparation conditions and the existence of saccharose on the crystal structure and electrochemical performance were characterized by XRD, SEM and electrochemical performance testing. The results show that all the samples are pure monoclinic Li3V2 （PO4）3; different conditions can not change the crystal structure and the lattice parameters, but it has effects on the particle size. The existence of saccharose can reduce the average particle size and particle aggregation, and then affect the electrochemical performances. The cycling performances of all the samples at low rate during 3.0-4.3 V display well due to the stable structure. The rate performance becomes worse with the increase of particle size. The particle aggregation and capacity at high rate also seriously reduce.
出处
《热加工工艺》
CSCD
北大核心
2013年第14期76-79,共4页
Hot Working Technology
