Abstract
High-voltage lithium metal batteries(LMBs)have been considered promising next-generation high-energy-density batteries.However,commercial carbonate electrolytes can scarcely be employed in LMBs owing to their poor compatibility with metallic lithium.N,N-dimethylacrylamide(DMAA)-a crosslinkable solubilizer with a high Gutmann donor number-is employed to facilitate the dissolution of insoluble lithium nitrate(LiNO3)in carbonate-based electrolytes and to form gel polymer electrolytes(GPEs)through in situ polymerization.The Li+solvation structure of the GPEs is regulated using LiNO3 and DMAA,which suppresses the decomposition of LiPF6 and facilitates the formation of an inorganic-rich solid electrolyte interface.Consequently,the Coulombic efficiency(CE)of the Li‖Cu cell assembled with a GPE increases to 98.5%at room temperature,and the high-voltage Li‖NCM622 cell achieves a capacity retention of 80.1%with a high CE of 99.5%after 400 cycles.The bifunctional polymer electrolytes are anticipated to pave the way for next-generation high-voltage LMBs.
基金项目
National Natural Science Foundation of China(51971250)
China Postdoctoral Science Foundation(2023M733933)
Natural Science Foundation of Hunan Province(2023JJ40759)
State Key Laboratory of Powder Metallurgy at Central South University()