Fluorinated graphite nanosheets for ultrahigh-capacity lithium primary batteries

• 作者: Xiao-Xia Yang Guan-Jun Zhang Bao-Sheng Bai Yu Li Yi-Xiao Li Yong Yang Xian Jian Xi-Wen Wang
• 来源期刊: 稀有金属（英文版）
• 年，卷（期）: 2021,（7）
• 所属期刊栏目: ORIGINAL ARTICLES
• 页码范围: 1708-1718
• 页数: 11页
• 语种: 英文

摘要

Traditional fluorinated carbon(CFx)batteries are greatly limited in their applications mostly because of inferior rate performances,initial voltage delay and low fluorine-to-carbon ratio below one.This work innovatively applies graphite nanosheets(NSs)as carbon source and optimizes the fluorination process at temperature range of 250-400℃ to prepare CFx NSs.Specifically,the edge defects and-CF2,-CF3 perfluorinated functional group active sites are introduced into NSs in the form of covalent/semi-covalent/semi-ionic bonds by adjusting the tempera-ture which also breaks the limit of fluorocarbon ratio to achieve ultra-thin microstructure with high performances.In the battery assembly process,a series of discharge electrolytes are introduced to improve the quality and realize the ultrahigh specific capacity.The optimized CFx-400℃ NSs deliver an excellent specific capacity of 921 mAh·g-1 at a current density of 10 mA·g-1 with a high energy density value of 2210 Wh·kg-1.Moreover,the new electrolytes are selected which not only serve as elec-trolytes but also can be loaded on CFx surface for various discharge reactions without affecting the actual battery function.Thus,the lightweight tabs and current collectors are selected to control the loading of active material and injection coefficient.The presented battery design strategy provides a new strategy to achieve an ultrahigh specific energy density of 1116 Wh·kg-1.