Weakly-solvated electrolytes(WSEs)utilizing solvents with weak coordination ability offer advantages for low-potential graphite anode owing to their facile desolvation process and anions-derived inorganic-rich solid e...Weakly-solvated electrolytes(WSEs)utilizing solvents with weak coordination ability offer advantages for low-potential graphite anode owing to their facile desolvation process and anions-derived inorganic-rich solid electrolyte interphase(SEI)film.However,these electrolytes face challenges in achieving a balance between the weak solvation affinity and high ionic conductivity,as well as between rigid inorganic-rich SEI and flexible SEI for long-term stability.Herein,we introduce 1,3-dioxolane(DOL)and lithium bis(trifluoromethanesulfonyl)-imide(LiTFSI)as functional additives into a WSE based on nonpolar cyclic ether(1,4-dioxane).The well-formulated WSE not only preserves the weakly solvated features and anion-dominated solvation sheath,but also utilizes DOL to contribute organic species for stabilizing the SEI layer.Benefitting from these merits,the optimized electrolyte enables graphite anode with excellent fast-charging performance(210 mAh/g at 5 C)and outstanding cycling stability(600 cycles with a capacity retention of 82.0%at room temperature and 400 cycles with a capacity retention of 80.4%at high temper-ature).Furthermore,the fabricated LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)||graphite full cells demonstrate stable operation for 140 cycles with high capacity retention of 80.3%.This work highlights the potential of tailoring solvation sheath and interphase properties in WSEs for advanced electrolyte design in graphite-based lithium-ion batteries.展开更多
基金support from the National Key Research and Development Program of China(No.2022YFB2402200)National Natural Science Foundation of China(No.22109028)+1 种基金Natural Science Foundation of Shanghai(No.22ZR1404400)Chenguang Program sponsored by Shanghai Education Development Foundation and Shanghai Municipal Education Commission(No.19CG01).
文摘Weakly-solvated electrolytes(WSEs)utilizing solvents with weak coordination ability offer advantages for low-potential graphite anode owing to their facile desolvation process and anions-derived inorganic-rich solid electrolyte interphase(SEI)film.However,these electrolytes face challenges in achieving a balance between the weak solvation affinity and high ionic conductivity,as well as between rigid inorganic-rich SEI and flexible SEI for long-term stability.Herein,we introduce 1,3-dioxolane(DOL)and lithium bis(trifluoromethanesulfonyl)-imide(LiTFSI)as functional additives into a WSE based on nonpolar cyclic ether(1,4-dioxane).The well-formulated WSE not only preserves the weakly solvated features and anion-dominated solvation sheath,but also utilizes DOL to contribute organic species for stabilizing the SEI layer.Benefitting from these merits,the optimized electrolyte enables graphite anode with excellent fast-charging performance(210 mAh/g at 5 C)and outstanding cycling stability(600 cycles with a capacity retention of 82.0%at room temperature and 400 cycles with a capacity retention of 80.4%at high temper-ature).Furthermore,the fabricated LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)||graphite full cells demonstrate stable operation for 140 cycles with high capacity retention of 80.3%.This work highlights the potential of tailoring solvation sheath and interphase properties in WSEs for advanced electrolyte design in graphite-based lithium-ion batteries.
