球磨方式对锂离子正极材料LiFePO_4性能的影响(英文)  

Effects of Ball-milling on the Preparation of LiFePO_4 Cathode Material for Lithium-ion Batteries

作　　者：唐致远[1] 高飞[1] 薛建军 

机构地区：[1]天津大学化工学院,天津300072 [2]广州鹏辉电池有限公司,广州511483

出　　处：《无机化学学报》2007年第8期1415-1420,共6页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金资助项目(No.2027304)。

摘　　要：采用高温固相合成法制备橄榄石型的LiFePO4正极材料,在合成过程中分别采用湿法球磨和干法球磨两种球磨方式。用X-射线衍射,扫描电镜,激光粒度测试等对合成材料进行表征,并对以LiFePO4为正极的电池进行电化学性能测试。结果表明,相对于干法球磨,湿法球磨制备的LiFePO4样品具有更好的电化学性能,0.2C放电的首次放电比容量为134.9mAh·g-1,并有优良的大电流放电性能及循环性能。这主要是因为采用湿法球磨制备的LiFePO4材料物相较纯、粒径均匀,与导电添加剂的接触更加紧密,从而提高了LiFePO4材料电化学性能。　Olivine LiFePO4/C composite powders were synthesized by solid-state reaction with wet ball-milling procedure. The powder properties and the electrochemical characteristics of the prepared samples were investigated in comparison with those samples obtained by dry ball-milling. The crystal structure and the electrochemical performance were characterized by XRD,SEM,laser particle-size distribution measurement and electrochemical performance testing. The olivine LiFePO4 obtained from wet ball-milling shows a maximum discharge capacity of 134.9 mAh·g^-1 at the C/5 rate. The composite also displays a better rate capability,a higher charge-discharge capacity and a more stable cycle-life than those samples from dry ball-milling. The improved electrode performance of samples by wet ball-milling originates mainly from very fine particles of sub-micron size and a homogeneous surface morphology. These powder characteristics increase the surface area of LiFePO4 particles and maximize the contact area with the conductor additives,resulting in enhanced electrochemical performance.

关 键 词：磷酸铁锂 球磨 粒径 正极材料 锂离子电池 

分 类 号：O614.111[理学—无机化学] TM912.9[理学—化学]