Synthesis and electrochemical properties of Al-doped LiVPO4F cathode materials for lithium-ion batte

• 作 者: ZHONG Shengkui YIN Zhoulan WANG Zhixing CHEN Qiyuan
• 机 构: College of Chemistry and Chemical Engineering Central South University, Changsha 410083, China;Depar
• 出 处: 稀有金属（英文版）
• 发表日期: 2007年5期
• 关键词: lithium-ion batteries cathode material LiVPO4F Al-doping carbothermal reduction

Al-doped LiVPO4F cathode materials LiAlxV1-xPO4F were prepared by two-step reactions based on a carbothermal reduction (CTR) process. The properties of the Al-doped LiVPO4F were investigated by X-ray diffraction (XRD),scanning electron microscopy (SEM), and electrochemical measurements. XRD studies show that the Al-doped LiVPO4F has the same triclinic structure (space group p(1)) as the undoped LiVPO4F. The SEM images exhibit that the particle size of Al-doped LiVPO4F is smaller than that of the undoped LiVPO4F and that the smallest particle size is only about 1 μm. The Al-doped LiVPO4F was evaluated as a cathode material for secondary lithium batteries, and exhibited an improved reversibility and cycleability, which may be attributed to the addition of Al3+ ion by stabilizing the triclinic structure.