摘要
以正磷酸铁为铁源,以葡萄糖、乙炔黑为碳源,采用碳热还原法合成橄榄石型磷酸铁锂。采用X射线衍射光谱法(XRD)、扫描电子显微镜法(SEM)及恒流充放电测试仪分别对合成样品的物相、晶胞参数、表面形貌及电性能进行测试与表征。对比分析了单一碳源掺杂与双碳源复合掺杂对材料结构及性能的影响。研究发现,合成的三组样品均为正交晶系的橄榄石型磷酸铁锂。其中双碳复合掺杂样品电性能最高为148.5mAh/g,倍率放电性能仍具有优势,10C时容量保持率为88.1%。
Olivine-type lithium iron phosphate was synthesized by carbothermal reduction method with ferric orthophosphate as the source of iron, glucose and acetylene black as the source of carbon. The crystal structure and electrochemical performance was characterized by XRD, SEM and electrochemical performance test. Different carbon-doped source and single or dual carbon-doped source in lithium iron phosphate were contrasted and analyzed in the structure and performance. The result demonstrate that the three samples are all olivine-type lithium iron phosphate. The dual carbon-doped sample has the most excellent electrochemical performance. The initial discharge capacity was achieved to 148.5 mAh/g at 0.1 C rate. It also has the best discharge capacity, and its discharge capacity at 10 C rate is up to 88.1% at 0.1 C rate.
出处
《电源技术》
CAS
CSCD
北大核心
2009年第8期658-661,共4页
Chinese Journal of Power Sources
关键词
锂离子电池
正极材料
磷酸铁锂
碳热还原法
lithium-ion battery
cathode material
LiFePO4
carbothermal reduction method
