摘要
采用KOH活化石墨烯,通过固相法制备了磷酸铁锂/碱活化石墨烯(LFP/CA-G)复合材料,通过SEM、Raman、XRD和电化学测试对复合材料的结构和性能进行表征,结果表明:通过固相法制备的LFP/CA-G复合材料稳定性较好,在1C倍率下循环50次的容量保持率为100%;LFP/CA-G复合材料的0.2C首次放电比容量为158.8m Ah/g,较磷酸铁锂/石墨烯(LFP/G)提高了3.1 m Ah/g;其3C倍率的放电比容量为139 m Ah/g,较LFP/G提高了7 m Ah/g。LFP/CA-G复合材料具有更好的可逆性,其阻抗更小。这是因为碱活化的石墨烯具有丰富的微孔,有利于缩短锂离子的迁移路径,减小了极化。
Chemically activated graphene(CA-G) was prepared by KOH etching. The LiFePOa/CA-G(LFP/CA-G) composite marterial was successfully prepared by solid-state method, characterized by SEM, Raman, XRD and electrochemical analysis. The results reveal that the obtained LFP/CA-G has excellent cycling stability and the capacity retention is near 100% after 50 cycles at 1C. The initial discharge capacity is 158.8 mAh/g at 0.2C, increased by 3.1 mAh/g than that of LiFePO4/graphene(LFP/G). The discharge capacity rate of 3C is 139 mAh/g, increased by 7 mAh/g than that of LFP/Ca The LFP/CA-G electrode has smaller resistance and better reversibility. That is because the LFP/CA-G electrode provides abundant porous channels for the diffusion of lithium ions.
作者
何湘柱
邓忠德
胡燚
孔令涌
尚伟丽
HE Xiangzhu DENG Zhongde HU Yi KONG Lingyong SHANG Weili(School of Chemical Engineering and Light Industry, Gnangdong University of Technology, Guangzhou 510006, China Shcnzhcn Dynanonic Co., Ltd, Shenzhen 518055, Guangdong Province, China)
出处
《电子元件与材料》
CAS
CSCD
2017年第2期45-49,共5页
Electronic Components And Materials
基金
广东省战略性新兴产业发展专项基金资助(No.2012BZ100104)
深圳市第四批战略性新兴产业发展专项资金资助(No.ZD201111070091A)
关键词
磷酸铁锂
固相法
碱活化石墨烯
复合材料
倍率性能
电化学性能
LiFePO4
solid state method
chemically activated graphene
composite
rate performance
electrochemical performance