At present,developing a simple strategy to effectively solve the shackles of volume expansion,poor conductivity and interface compatibility faced by Si-C anode in lithium batteries(LIBs)is the key to its commercializa...At present,developing a simple strategy to effectively solve the shackles of volume expansion,poor conductivity and interface compatibility faced by Si-C anode in lithium batteries(LIBs)is the key to its commercialization.Here,low-cost nano-Si powders were prepared from Si-waste of solar-cells by sanding treatment,which can effectively reduce the commercialization cost for Si-C anode.Furthermore,micro-nano structured Gr@Si/C/TiO_(2) anode materials with graphite(Gr)as the inner core,TiO_(2)-doped and carbon-coated Si as the outer coating-layer,were synthesized at kilogram-scale per milling batch.Comprehensive characterization results indicate that TiO_(2)-doped carbon layer can improve the interface compatibility with the electrolyte,further promote the reduction of electrode polarization,and finally enhance the battery performance for the Gr@Si/C/TiO_(2) anodes.Accordingly,Gr@Si/C/TiO_(2) composites can output excellent LIB performance,especially with high initial coulombic efficiency(ICE)of 82.51%and large average reversible capacity of~810 mA h g^(-1) at 0.8 A g^(-1) after 1000 cycles.Moreover,Gr@Si/C/TiO_(2)‖NCM811 pouch full cells deliver impressive performance especially with high energy density of~489.3 W h kg^(-1) based on the total weight of active materials,suggesting its promising application in the high performance LIBs.展开更多
Developing an effective method to synthesize high-performance high-voltage LiCoO_(2) is essential for its industrialization in lithium batteries(LIBs).This work proposes a simple mass-produced strategy for the first t...Developing an effective method to synthesize high-performance high-voltage LiCoO_(2) is essential for its industrialization in lithium batteries(LIBs).This work proposes a simple mass-produced strategy for the first time,that is,negative temperature coefficient thermosensitive Pr_(6)O_(11) nanoparticles are uniformly modified on LiCoO_(2) to prepare LiCoO_(2)@Pr_(6)O_(11)(LCO@PrO)via a liquid-phase mixing combined with annealing method.Tested at 274 mA g−1,the modified LCO@PrO electrodes deliver excellent 4.5 V high-voltage cycling performance with capacity retention ratios of 90.8%and 80.5%at 25 and 60℃,being much larger than those of 22.8%and 63.2%for bare LCO electrodes.Several effective strategies were used to clearly unveil the performance enhancement mechanism induced by Pr_(6)O_(11) modification.It is discovered that Pr_(6)O_(11) can improve interface compatibility,exhibit improved conductivity at elevated temperature,thus enhance the Li^(+)diffusion kinetics,and suppress the phase transformation of LCO and its resulting mechanical stresses.The 450 mAh LCO@PrO‖graphite pouch cells show excellent LIB performance and improved thermal safety characteristics.Importantly,the energy density of such pouch cell was increased even by~42%at 5 C.This extremely convenient technology is feasible for producing high-energy density LIBs with negligible cost increase,undoubtedly providing important academic inspiration for industrialization.展开更多
基金jointly supported by the Natural Science Foundations of China(22179020,12174057)the Fujian Natural Science Foundation for Distinguished Young Scholars(2020J06042)+1 种基金the Foreign Science and Technology Cooperation Project of Fuzhou Science and Technology Bureau(2021-Y-086)the Cultivation plan of outstanding young scientific research talents of Fujian Education Department(J1-1323)。
文摘At present,developing a simple strategy to effectively solve the shackles of volume expansion,poor conductivity and interface compatibility faced by Si-C anode in lithium batteries(LIBs)is the key to its commercialization.Here,low-cost nano-Si powders were prepared from Si-waste of solar-cells by sanding treatment,which can effectively reduce the commercialization cost for Si-C anode.Furthermore,micro-nano structured Gr@Si/C/TiO_(2) anode materials with graphite(Gr)as the inner core,TiO_(2)-doped and carbon-coated Si as the outer coating-layer,were synthesized at kilogram-scale per milling batch.Comprehensive characterization results indicate that TiO_(2)-doped carbon layer can improve the interface compatibility with the electrolyte,further promote the reduction of electrode polarization,and finally enhance the battery performance for the Gr@Si/C/TiO_(2) anodes.Accordingly,Gr@Si/C/TiO_(2) composites can output excellent LIB performance,especially with high initial coulombic efficiency(ICE)of 82.51%and large average reversible capacity of~810 mA h g^(-1) at 0.8 A g^(-1) after 1000 cycles.Moreover,Gr@Si/C/TiO_(2)‖NCM811 pouch full cells deliver impressive performance especially with high energy density of~489.3 W h kg^(-1) based on the total weight of active materials,suggesting its promising application in the high performance LIBs.
基金jointly supported by the Natural Science Foundations of China(Nos.22179020,12174057)Fujian Natural Science Foundation for Distinguished Young Scholars(Grant No.2020J06042)+2 种基金Foreign science and technology cooperation project of Fuzhou Science and Technology Bureau(No.2021-Y-086)Natural Science Foundation of Fujian Province(Grant No.2018J01660)Cultivation plan of outstanding young scientific research talents of Fujian Education Department(Grant No.J1-1323).
文摘Developing an effective method to synthesize high-performance high-voltage LiCoO_(2) is essential for its industrialization in lithium batteries(LIBs).This work proposes a simple mass-produced strategy for the first time,that is,negative temperature coefficient thermosensitive Pr_(6)O_(11) nanoparticles are uniformly modified on LiCoO_(2) to prepare LiCoO_(2)@Pr_(6)O_(11)(LCO@PrO)via a liquid-phase mixing combined with annealing method.Tested at 274 mA g−1,the modified LCO@PrO electrodes deliver excellent 4.5 V high-voltage cycling performance with capacity retention ratios of 90.8%and 80.5%at 25 and 60℃,being much larger than those of 22.8%and 63.2%for bare LCO electrodes.Several effective strategies were used to clearly unveil the performance enhancement mechanism induced by Pr_(6)O_(11) modification.It is discovered that Pr_(6)O_(11) can improve interface compatibility,exhibit improved conductivity at elevated temperature,thus enhance the Li^(+)diffusion kinetics,and suppress the phase transformation of LCO and its resulting mechanical stresses.The 450 mAh LCO@PrO‖graphite pouch cells show excellent LIB performance and improved thermal safety characteristics.Importantly,the energy density of such pouch cell was increased even by~42%at 5 C.This extremely convenient technology is feasible for producing high-energy density LIBs with negligible cost increase,undoubtedly providing important academic inspiration for industrialization.