摘要
为了获得颗粒均匀、细小和优异电化学性能的LiFePO4,采用不同碳热还原方法(固相反应中用乙炔黑作碳源,固相反应中用蔗糖作碳源,半固相反应中用蔗糖作碳源)合成了LiFePO4。制备样品分别用XRD和SEM进行表征,通过充放电试验测试电化学性能。结果显示:半固相碳热还原反应制得的样品颗粒粒径最小、电化学性能最佳。在2.0～4.0V(Vs.Li)范围内、15mA·g-1电流密度下放电,首次放电比容量高达到162mAh·g-1,是理论容量的95.3%;该样品也具有稳定的循环行为。半固相碳热还原法是制备锂离子电池正极材料LiFePO4一种有潜力的合成方法。
In order to obtain fine-paiticle LiFePO4 with excellent electrochemical performance, several different carbothermal reduction methods （solid state reaction using acetylene black as carbon source, solid state reaction using sucrose as carbon source,and half solid state reaction using sucrose as carbon source） were used to synthesize LiFePO4 powders.LiFePO4 powders were characterized by X- ray powder diffraction and scanning electron microscopy and its electrochemical properties were investigated by charge-discharge tests. The results showed that the sample, synthesized by half solid state carbothennal reduction reaction, had the smallest particle size and the best electrochemical performance, and delivered a high capacity of 162 mAh- g^-1 at the 15 mA- g^-1 rate between 2.0 and 4.0 V （Vs. Li）, i.e. 95.3 % of the theoretical capacity. The sample also displayed stable cycle-life. Consequently, the half solid state carbothermal reduction method is a promising synthetic process of LiFePO4 cathode materials for lithium ion batteries.
出处
《四川大学学报（工程科学版）》
EI
CAS
CSCD
北大核心
2005年第4期77-80,共4页
Journal of Sichuan University (Engineering Science Edition)
关键词
磷酸锂铁
碳热还原
锂离子电池
正极材料
lithium iron phosphate
carbothermal reduction
lithium-ion batteries
cathodic materials
