Ionic solid-like conductor-assisted polymer electrolytes for solid-state lithium metal batteries  

作　　者：Shuaishuai Yan Hao Liu Xiaoxia Chen Yang Lu Qingbin Cao Kai Liu 

机构地区：[1]State Key Laboratory of Chemical Engineering,Department of Chemical Engineering,Tsinghua University,Beijing 100084,China [2]Hefei Institute for Public Safety Research,Tsinghua University,Hefei 230601,China [3]Beijing Huairou Laboratory,Beijing 101400,China

出　　处：《Science China Chemistry》2024年第12期4116-4124,共9页中国科学（化学英文版）

基　　金：supported by the National Key Research and Development Program of China(2023YFB2503700,and 2023YFC3008804);the National Natural Science Foundation of China(22071133);Beijing Municipal Science&Technology Commission(Z231100006123003);the Science Foundation of China Academy of Safety Science and Technology(2023JBKY17)。

摘　　要：Solid polymer electrolytes(SPEs)have attracted extensive attention by virtue of lightweight and flexible processability for solidstate lithium metal batteries(LMBs)with high energy density and intrinsic safety.However,the SPEs suffer from the trade-off effect between ionic conductivity and mechanical strength.Herein,we report an ionic solid-like conductor with high Li+conductivity and good thermal stability as the conductive phase of polymer electrolytes for advanced LMBs.Using poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)as the polymer matrix,the ionic solid-like conductor can be regarded as a solid plasticizer due to its advantages of non-fluidity and non-leakage.It increases the amorphous region and the dissociation degree of lithium salts in SPEs,while minimizing the loss of mechanical properties.As a result,the Li+conductivity of SPEs incorporating the ionic solid-like conductor is enhanced by four orders of magnitude compared to the blank PVDF-HFPbased electrolyte.The optimized SPE membranes can be processed as thin as 50μm with a high Young's modulus of 16.8 MPa,therefore ensuring stable long-term cycling of solid-state LMBs.The Li/Li symmetric cells stably cycled for more than 750 h without short circuits,and the LiFePO_(4)/Li solid-state batteries demonstrate excellent electrochemical performance over 350cycles with a capacity retention of 82.5%.This work provides a new strategy for designing ionic solid-like conductors as solid plasticizers for high-performance polymer electrolytes.

关 键 词：ionic solid-like conductors polymer electrolytes solid plasticizers solid-state lithium metal batteries 

分 类 号：O631[理学—高分子化学] TM912[理学—化学]