Preparation and Performance of LiFePO_4/C Composites
TIAN Jian-hua~1,LI Xiang-jun~(1,2),WEI Chen-xian~1,SHAN Zhong-qiang~1,GAO Xue-ping~3(1.School of Chemical Engineering and Technology,Tianjin University,Tianjin 300072,China;2.Zhonghe Huayuan Titanium Co.,Ltd.,Lanzhou 732850,Gansu Province,China;3.Institute of New Energy Chemical Material,Nankai University,Tianjin 300071,China)
(1,2),WEI Chen-xian~1,SHAN Zhong-qiang~1,GAO Xue-ping~3(1.School of Chemical Engineering and Technology,Tianjin University,Tianjin 300072,China;2.Zhonghe Huayuan Titanium Co.,Ltd.,Lanzhou 732850,Gansu Province,China;3.Institute of New Energy Chemical Material,Nankai University,Tianjin 300071,China
Abstract：
LiFePO_4/C composites,as a kind of positive electrode materials in Li-ion batteries,were prepared by high temperature solid-state reactions.LiFePO_4 and LiFePO_4/C particles in the size from nanometer to sub-micrometer were obtained through pretreatment at 300 ℃ and calcination at 650 ℃.X-ray diffraction (XRD) analysis showed that the prepared LiFePO_4 and LiFePO_4/C composites had a structure of olive-type phase and with a high degree of purity.Among LiFePO_4 and LiFePO_4/C composites prepared with different carbon materials,such as the acetylene black,Vulcan XC-72 carbon black,scalelike graphite,anisotropic graphite powders and glucose,LiFePO_4/C samples prepared with glucose exhibited the best recharge-discharge cyclic performance.The cyclic performance was improved while the operation temperature was increased from room temperature to 40 ℃.This is because of the highe electronic conductivity and the more rapid diffusion rate of Li~+ in the LiFePO_4/C structure.
CHEN Zhao-hui,DAHN J R.Reducing carbon in LiFePO4/C composite electrodes to maximize specific energy,volumetric energy,and tap density[J].Journal of theElectrochemical Society,2002,149(9):1 184-1 189.
SYLVAIN F,CAROLE B.Comparison between differentLiFePO4synthesis routes and their influence on its physico-chemical properties[J].Journal of Power Sources.2003,119:252-257
2007, Vol. 24 
