摘要
以甘氨酸为络合剂,蔗糖为碳源,采用溶胶-凝胶法制备了LiFePO4、LiFePO4/C正极材料。利用TG、XRD、SEM测试技术对材料的热稳定性、物相结构、形貌进行表征。结果表明:LiFePO4和LiFePO4/C都具有单一的橄榄石型晶体结构,与纯相LiFePO4相比,LiFePO4/C具有更小的颗粒粒径和更好的电化学性能,以0.1 C、0.5 C倍率放电,首次放电比容量分别为157.5、140.7 mAh/g,循环20次后容量保持为152.4、130.2 mAh/g。
LiFePO4and LiFePO4/C composite cathodes were prepared by a sol-gel method using glycine as chelating agent and sucrose as carbon source.The thermostability,phase structure,surface morphology and electrochemical performance of LiFePO4and LiFePO4∕C composite were characterized by TG-DTG,XRD,SEM and galvanostatic charge-discharge respectively.The results show that LiFePO4 and LiFePO4/C are both simple pure phase olivine-type.Compared with pure phase LiFePO4,LiFePO4/C has smaller particle size and better electrochemical performance and the initial discharge capacity of LiFePO4/C are 157.5 mAh/g at 0.1 C,and 140.7 mAh/g at 0.2 C,which maintain discharge capacity of 152.4 mAh/g and 130.2 mAh/g after 20 cycles.
出处
《电源技术》
CAS
CSCD
北大核心
2010年第8期818-821,共4页
Chinese Journal of Power Sources
基金
湖南省教育厅优秀青年项目(07B076)
湖南省科技厅科技计划项目(2008FJ3097)
