Practical high-voltage lithium metal batteries hold promise for high energy density applications,but face stability challenges in electrolytes for both 4 V-class cathodes and lithium anode.To address this,we delve int...Practical high-voltage lithium metal batteries hold promise for high energy density applications,but face stability challenges in electrolytes for both 4 V-class cathodes and lithium anode.To address this,we delve into the positive impacts of two crucial moieties in electrolyte chemistry:fluorine atom(-F)and cyano group(-CN)on the electrochemical performance of polyether electrolytes and lithium metal batteries.Cyano-bearing polyether electrolytes possess strong solvation,accelerating Li^(+)desolvation with minimal SEI impact.Fluorinated polyether electrolytes possess weak solvation,and stabilize the lithium anode via preferential decomposition of F-segment,exhibiting nearly 6000-h stable cycling of lithium symmetric cell.Furthermore,the electron-withdrawing prop-erties of-F and-CN groups significantly bolster the high-voltage tolerance of copolymer electrolyte,extending its operational range up to 5 V.This advance-ment enables the development of 4 V-class lithium metal batteries compatible with various cathodes,including 4.45 V LiCoO_(2),4.5 V LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2),and 4.2 V LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2).These findings provide insights into design prin-ciples centered around polymer components for high-performance polymer electrolytes.展开更多
基金National Key Research and Development Program,Grant/Award Number:2019YFA0705701National Natural Science Foundation of China,Grant/Award Numbers:22179149,22075329,22008267,51573215,21978332+1 种基金Guangdong Basic and Applied Basic Research Foundation,Grant/Award Number:2021A0505030022Research and Development Project of Henan Academy of Sciences China,Grant/Award Number:232018002。
文摘Practical high-voltage lithium metal batteries hold promise for high energy density applications,but face stability challenges in electrolytes for both 4 V-class cathodes and lithium anode.To address this,we delve into the positive impacts of two crucial moieties in electrolyte chemistry:fluorine atom(-F)and cyano group(-CN)on the electrochemical performance of polyether electrolytes and lithium metal batteries.Cyano-bearing polyether electrolytes possess strong solvation,accelerating Li^(+)desolvation with minimal SEI impact.Fluorinated polyether electrolytes possess weak solvation,and stabilize the lithium anode via preferential decomposition of F-segment,exhibiting nearly 6000-h stable cycling of lithium symmetric cell.Furthermore,the electron-withdrawing prop-erties of-F and-CN groups significantly bolster the high-voltage tolerance of copolymer electrolyte,extending its operational range up to 5 V.This advance-ment enables the development of 4 V-class lithium metal batteries compatible with various cathodes,including 4.45 V LiCoO_(2),4.5 V LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2),and 4.2 V LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2).These findings provide insights into design prin-ciples centered around polymer components for high-performance polymer electrolytes.
