Synergistic coupling among Mg_(2)B_(2)O_(5),polycarbonate and N,Ndimethylformamide enhances the electrochemical performance of PVDF-HFP-based solid electrolyte  

作　　者：Yutong Jing Qiang Lv Yujia Chen Bo Wang Bochen Wu Cheng Li Shengbo Yang Zhipeng He Dianlong Wang Huakun Liu Shixue Dou 

机构地区：[1]MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage,State Key Laboratory of Urban Water Resource and Environment,School of Chemistry and Chemical Engineering,Harbin Institute of Technology,Harbin 150001,Heilongjiang,China [2]Institute of Energy Material Science,University of Shanghai for Science and Technology,Shanghai 200093,China [3]Institute for Superconducting&Electronic Materials,Australian Institute of Innovative Materials,University of Wollongong,Wollongong,NSW 2500,Australia

出　　处：《Journal of Energy Chemistry》2024年第7期158-168,共11页能源化学（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.51604089,51874110,22173066,and 21903058);Natural Science Foundation of Heilongjiang Province(Grant No.YQ2021B004).

摘　　要：Polymer solid electrolytes(SPEs)based on the[solvate-Li+]complex structure have promising prospects in lithium metal batteries(LMBs)due to their unique ion transport mechanism.However,the solvation structure may compromise the mechanical performance and safety,hindering practical application of SPEs.In this work,a composite solid electrolyte(CSE)is designed through the organic-inorganic syner-gistic interaction among N,N-dimethylformamide(DMF),polycarbonate(PC),and Mg_(2)B_(2)O_(5) in poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP).Flame-retardant Mg_(2)B_(2)O_(5) nanowires provide non-flammability to the prepared CSEs,and the addition of PC improves the dispersion of Mg_(2)B_(2)O_(5) nanowires.Simultaneously,the organic-inorganic synergistic action of PC plasticizer and Mg_(2)B_(2)O_(5) nanowires pro-motes the dissociation degree of LiTFSI and reduces the crystallinity of PVDF-HFP,enabling rapid Li ion transport.Additionally,Raman spectroscopy and DFT calculations confirm the coordination between Mg atoms in Mg_(2)B_(2)O_(5) and N atoms in DMF,which exhibits Lewis base-like behavior attacking adjacent C-F and C-H bonds in PVDF-HFP while inducing dehydrofluorination of PVDF-HFP.Based on the syner-gistic coupling of Mg_(2)B_(2)O_(5),PC,and DMF in the PVDF-HFP matrix,the prepared CSE exhibits superior ion conductivity(9.78×10^(-4) s cm^(-1)).The assembled Li symmetric cells cycle stably for 3900 h at a current density of 0.1 mA cm^(-2) without short circuit.The LFP||Li cells assembled with PDL-Mg_(2)B_(2)O_(5)/PC CSEs show excellent rate capability and cycling performance,with a capacity retention of 83.3%after 1000 cycles at 0.5 C.This work provides a novel approach for the practical application of organic-inorganic Synergistic CSEs in LMBs.

关 键 词：Composite solid electrolytes Safe Li metal batteries Synergistic coupling effect Poly(vinylidene fluoride-co-hexafluoropro pylene) 

分 类 号：O646[理学—物理化学] TM912[理学—化学]