“In-N-out” design enabling high-content triethyl phosphate-based non-flammable and high-conductivity electrolytes for lithium-ion batteries  

作　　者：Mengchuang Liu Fenfen Ma Zicheng Ge Ziqi Zeng Qiang Wu Hui Yan Yuanke Wu Sheng Lei Yanli Zhu Shijie Cheng Jia Xie 

机构地区：[1]State Key Laboratory of Advanced Electromagnetic Engineering and Technology,School of Electrical and Electronic Engineering,Huazhong University of Science and Technology,Wuhan,430074,China [2]School of Chemistry and Chemical Engineering,Huazhong University of Science and Technology,Wuhan,430074,China [3]GuSu Laboratory of Materials,Suzhou,215123,China [4]Institute of Metal Research,Chinese Academy of Sciences,Shenyang,110000,China [5]State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology,Beijing,100081,China

出　　处：《Science China Chemistry》2024年第2期724-731,共8页中国科学（化学英文版）

基　　金：supported by the National Key Research and Development Program of China (2022YFB2404800);the National Natural Science Foundation of China (52022013,51974031 and U22A20438)。

摘　　要：Safety issues related to flammable electrolytes in lithium-ion batteries(LIBs) remain a major challenge for their extended applications.The use of non-flammable phosphate-based electrolytes has proved the validity in inhibiting the combustion of LIBs.However,the strong interaction between Li^(+) and phosphate leads to a dominant solid electrolyte interphase(SEI) with limited electronic shielding,resulting in the poor Li^(+) intercalation at the graphite(Gr) anode when using high-phosphate-content electrolytes.To mitigate this issue and improve Li^(+) insertion,we propose an “In-N-Out” strategy to render phosphates “noncoordinative”.By employing a combination of strongly polar solvents for a “block effect” and weakly polar solvents for a “drag effect”,we reduce the Li^(+)–phosphate interaction.As a result,phosphates remain in the electrolyte phase(“In”),minimizing their impact on the incompatibility with the Gr electrode(“Out”).We have developed a non-flammable electrolyte with high triethyl phosphate(TEP) content(>60 wt.%),demonstrating the excellent ion conductivity(5.94 mS cm^(-1) at 30 ℃) and reversible Li^(+) intercalation at a standard concentration(~1 mol L^(-1)).This approach enables the manipulation of multiple electrolyte functions and holds the promise for the development of safe electrochemical energy storage systems using non-flammable electrolytes.

关 键 词：lithium-ion batteries graphite anode high-phosphate-content electrolytes non-flammable electrolyte excellent ion conductivity standard concentration 

分 类 号：O646.1[理学—物理化学] TM912[理学—化学]