摘要
分别使用两种结构不同的氟化碳材料(CF_(x)-A、CF_(x)-B),电解液LiPF6、LiBF4以及锂带制备5 Ah的18650型圆柱电池,利用XRD、SEM、EDS等测试技术对材料的形貌结构进行表征分析,并对电池进行恒功率恒流放电测试,研究了不同的电解液、氟化碳材料、环境温度和高温贮存时长对电池电化学性能的影响。试验结果表明,LiBF4与氟化碳材料的匹配协同效果较好,但LiBF4性能的发挥受温度影响较大,环境温度从50℃下降到-20℃时,比容量下降约25%~35%。相较于CF_(x)-A,CF_(x)-B的层间距和比表面积较大,Li/CF_(x)-B电池具有更高的放电电压,较好的倍率性能,但容量偏低;而Li/CF_(x)-A电池的放电平台更平稳、容量更高、高温贮存性能更好,但倍率性能较差。
In this paper,two fluorinated carbon materials with different structures(CF_(x)-A,CF_(x)-B),electrolytes(LiPF6,LiBF4)and lithium ribbons were used to prepare 5 Ah 18650 cylindrical batteries.The morphologies and structures were characterized and analyzed,and the batteries were tested with constant powers and constant currents discharges.The effects of different electrolytes,fluorinated carbon materials,ambient temperatures and high temperature storage times on the electrochemical performances of the batteries were studied.The experimental results show that the matching and synergistic effects of LiBF4 with fluorinated carbon materials are superior,but the performances of LiBF4 are greatly affected by ambient temperatures.When the ambient temperature drops from 50℃to-20℃,the specific capacity decreases by about 25%~35%.Compared with CF_(x)-A,CF_(x)-B has larger interlayer spacing and specific surface area,Li/CF_(x)-B battery has higher discharge voltages,better rate performances,but lower capacity;while Li/CF_(x)-A cell's platform discharge is more stable,the capacity is higher,and the high temperature storage performance is better,but the rate performance is poor.
作者
张红梅
徐志涛
王京亮
王庆杰
石斌
ZHANG Hongmei;XU Zhitao;WANG Jingliang;WANG Qingjie;SHI Bin(Guizhou Meiling Power Source Co.,Ltd.,of CASIC,Zunyi Guizhou 563003,China;Equipment Department of Rocket Army in Zunyi Military Representative Office,Zunyi Guizhou 563003,China)
出处
《电源技术》
CAS
北大核心
2023年第8期1082-1086,共5页
Chinese Journal of Power Sources
基金
国防基础科研计划(JCKY2019204C025)。
关键词
氟化碳材料
电解液
温度依赖性
贮存特性
fluorinated carbon materials
electrolyte
temperature dependence
storage characteristic
