Li-O_(2) cells with high theoretical energy density are considered the next-generation electrochemical energy storage device.A complex electrochemical environment under O_(2) conditions hinders the further development...Li-O_(2) cells with high theoretical energy density are considered the next-generation electrochemical energy storage device.A complex electrochemical environment under O_(2) conditions hinders the further development of the Li-metal anode in Li-O_(2) cells.The composition of the solvent in the electrolyte has a significant impact on the electrochemical performance of Li-metal under an O_(2) atmosphere.Herein,the compatibility of typical diglyme(G2),triglyme(G3),and tetraglyme(G4) ether-based solvents with Li-metal anode in O_(2) environment is comprehensively unraveled from the perspective of both Li/Li symmetric cells in a harsh O_(2) environment and Li-O_(2) cells.Electrolyte with G2-based solvent can promote the formation of a thin and uniform solid electrolyte interphase(SEI) film,facilitating dendrite growth suppression and rechargeability of Li/Li symmetric cells under O_(2) atmosphere.However,its poor oxidative stability under high voltage impedes further long-term cycling of the Li-O_(2) cell.The evolution of SEI film with fragmentation accumulation and reconstruction during cycling leads to poor reversibility of both Li/Li symmetric cells and Li-O_(2)cells in G3-based electrolyte.In G4-based electrolyte,a relatively uniform SEI film and side reaction suppression resulting from the oxidative stability of the electrolyte together contribute to long-term stable cycle life of Li-O_(2) cells.Therefore,among three ether-based solvents(G2,G3,and G4),G2 is more effective in enhancing the reversibility of Li/Li symmetric cell under O_(2)-rich conditions,while G4 is more conducive to the rechargeability of Li-O_(2) cell.This work provides new insights for suitable solvent selection of stable Li-metal anode under O_(2) environment and has also paved a novel research avenue for other metal-based batteries in a harsh O_(2) atmosphere.展开更多
基金supported by the Open Fund of Fujian Provincial Key Laboratory of Functional Materials and Applications of Xiamen University of Technology (fma2024006)the Education Research Projects for Young and Middle-aged Teachers in Fujian Province(JZ240060)+2 种基金the Natural Science Foundation of Xiamen,China(3502Z202471071)the Talents Introduction Program of Xiamen University of Technology (YKJ23016R)the National Natural Science Foundation of China (22509171,22021001,22179111,22288102,21974117,22202082)。
文摘Li-O_(2) cells with high theoretical energy density are considered the next-generation electrochemical energy storage device.A complex electrochemical environment under O_(2) conditions hinders the further development of the Li-metal anode in Li-O_(2) cells.The composition of the solvent in the electrolyte has a significant impact on the electrochemical performance of Li-metal under an O_(2) atmosphere.Herein,the compatibility of typical diglyme(G2),triglyme(G3),and tetraglyme(G4) ether-based solvents with Li-metal anode in O_(2) environment is comprehensively unraveled from the perspective of both Li/Li symmetric cells in a harsh O_(2) environment and Li-O_(2) cells.Electrolyte with G2-based solvent can promote the formation of a thin and uniform solid electrolyte interphase(SEI) film,facilitating dendrite growth suppression and rechargeability of Li/Li symmetric cells under O_(2) atmosphere.However,its poor oxidative stability under high voltage impedes further long-term cycling of the Li-O_(2) cell.The evolution of SEI film with fragmentation accumulation and reconstruction during cycling leads to poor reversibility of both Li/Li symmetric cells and Li-O_(2)cells in G3-based electrolyte.In G4-based electrolyte,a relatively uniform SEI film and side reaction suppression resulting from the oxidative stability of the electrolyte together contribute to long-term stable cycle life of Li-O_(2) cells.Therefore,among three ether-based solvents(G2,G3,and G4),G2 is more effective in enhancing the reversibility of Li/Li symmetric cell under O_(2)-rich conditions,while G4 is more conducive to the rechargeability of Li-O_(2) cell.This work provides new insights for suitable solvent selection of stable Li-metal anode under O_(2) environment and has also paved a novel research avenue for other metal-based batteries in a harsh O_(2) atmosphere.
