Silicon(Si)is a promising anode candidate for next-generation lithium-ion batteries(LIBs),but it suffers from poor electronic conductivity and dramatic volume variation during cycling,which poses a critical challenge ...Silicon(Si)is a promising anode candidate for next-generation lithium-ion batteries(LIBs),but it suffers from poor electronic conductivity and dramatic volume variation during cycling,which poses a critical challenge for stable battery operation.To mitigate these issues simultaneously,we propose a"double carbon synergistic encapsulation"strategy,namely thin carbon shell and nitrogen/phosphorus co-doped two-dimensional(2D)carbon sheet dual encapsulate Si nanoparticles(denoted as 2D NPC/C@Si).This double carbon structure can serve as a conductive medium and buffer matrix to accommodate the volume expansion of Si nanoparticles and enable fast electron/ion transport,which promotes the formation of a stable solid electrolyte interphase film during cycling.Through structural advantages,the resulting 2 D NPC/C@Si electrode demonstrates a high reversible capacity of592 mAh·g^(-1) at 0.2 A·g^(-1) with 90.5%excellent capacity retention after 100 cycles,outstanding rate capability(148 mAh·g^(-1) at 8 A·g^(-1)),and superior long-term cycling stability(326 mAh·g^(-1) at 1 A·g^(-1) for 500 cycles,86%capacity retention).Our findings elucidate the development of high-performance Si@C composite anodes for advanced LTBs.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant Nos.52072323,21805278 and 51872098)the Leading Project Foundation of Science Department of Fujian Province(No.2018H0034)+2 种基金the“Double-First Class”Foundation of Materials and Intelligent Manufacturing Discipline of Xiamen Universitythe Opening Project of National Joint Engineering Research Center for Abrasion Control and Molding of Metal MaterialsHenan Key Laboratory of High-temperature Structural and Functional Materials,Henan University of Science and Technology(No.HKDNM2019013)。
文摘Silicon(Si)is a promising anode candidate for next-generation lithium-ion batteries(LIBs),but it suffers from poor electronic conductivity and dramatic volume variation during cycling,which poses a critical challenge for stable battery operation.To mitigate these issues simultaneously,we propose a"double carbon synergistic encapsulation"strategy,namely thin carbon shell and nitrogen/phosphorus co-doped two-dimensional(2D)carbon sheet dual encapsulate Si nanoparticles(denoted as 2D NPC/C@Si).This double carbon structure can serve as a conductive medium and buffer matrix to accommodate the volume expansion of Si nanoparticles and enable fast electron/ion transport,which promotes the formation of a stable solid electrolyte interphase film during cycling.Through structural advantages,the resulting 2 D NPC/C@Si electrode demonstrates a high reversible capacity of592 mAh·g^(-1) at 0.2 A·g^(-1) with 90.5%excellent capacity retention after 100 cycles,outstanding rate capability(148 mAh·g^(-1) at 8 A·g^(-1)),and superior long-term cycling stability(326 mAh·g^(-1) at 1 A·g^(-1) for 500 cycles,86%capacity retention).Our findings elucidate the development of high-performance Si@C composite anodes for advanced LTBs.
