Wide-temperature range and high safety electrolytes for highvoltage Li-metal batteries  

作　　者：Anran Pan Zhicheng Wang Fengrui Zhang Lei Wang Jingjing Xu Jieyun Zheng Jianchen Hu Chenglong Zhao Xiaodong Wu 

机构地区：[1]i-lab,Suzhou Institute of Nano-Tech and Nano-Bionics(SINANO),Chinese Academy of Sciences,Suzhou 215123,China [2]Nano Science and Technology Institute,University of Science and Technology of China,Hefei 230026,China [3]Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China [4]College of Textile and Clothing Engineering,Soochow University,Suzhou 215123,China [5]Phylion battery Co.,Ltd.,Suzhou 215123,China

出　　处：《Nano Research》2023年第6期8260-8268,共9页纳米研究（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.22179142 and 22075314);The XPS characterization is supported by Nano-X(Vacuum Interconnected Nanotech Workstation,Chinese Academy of Sciences,Suzhou 215123,China).

摘　　要：Along with the keeping growing demand for high-energy-density energy storage system,high-voltage Li-metal batteries(LMBs)have attracted many attentions.In view of many defects of the commercial electrolytes,such as flammability,limited operation temperature range,and severe Li dendrite growth,non-flammable phosphate-based localized highly concentrated electrolytes(LHCE)have been explored as one of the safe electrolytes for LMBs.But until now there is rare report on wide-temperature range LMBs using phosphate-based electrolytes.Here,we prepare a wide-temperature LHCE,which is composed of lithium difluoro(oxalato)borate(LiDFOB),triethyl phosphate(TEP),and 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether(HFE),and explore the applicability in wide-temperature LMBs from−40 to 70℃.In the LHCE,both TEP and HFE are non-flammable,and Li^(+) is highly coordinated with TEP and DFOB^(−),which can effectively inhibit the TEP decomposition on anode,and facilitate the preferential reduction of DFOB^(−),thus obtain a robust solid electrolyte interphase(SEI)to suppress Li dendrite growth and side reactions.Therefore,this LHCE can not only endow Li/Cu and Li/Li cells with high Coulombic efficiency(CE)and long cycling lifespan,but also be applied to LiFePO_(4)(LFP)/Li and LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)(NCM523)/Li LMBs.Most importantly,the NCM523/Li LMBs with LHCE can deliver stable cycling performance at 4.5 V high-voltage and high-temperature(70℃),as well as excellent low-temperature capacity retention even though both charging and discharging process were carried out at−40℃.

关 键 词：safe electrolytes wide-temperature NON-FLAMMABLE high-voltage batteries 

分 类 号：TM912[电气工程—电力电子与电力传动]