能源化学(英文版) ›› 2020, Vol. 49 ›› Issue (10): 233-242.DOI: 10.1016/j.jechem.2020.02.044

• • 上一篇    下一篇

Exfoliated multi-layered graphene anode with the broadened delithiation voltage plateau below 0.5 V

Xinlong Maa, Xinyu Songb, Yushu Tanga, Enzuo Liuc, Chenggen Xua, Chuanlei Qia, Yun Lia, Jinsen Gaoa, Yongfeng Lia   

  1. a State Key Laboratory of Heavy Oil Processing,China University of Petroleum,Beijing 102249,China;
    b Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province,Yancheng Institute of Technology,Yancheng 224051,Jiangsu,China;
    c School of Materials Science and Engineering and Tianjin Key Laboratory of Composites and Functional Materials,Tianjin University,Tianjin 300072,China
  • 收稿日期:2020-01-21 修回日期:2020-02-24 出版日期:2020-10-15 发布日期:2020-12-18
  • 通讯作者: Yongfeng Li
  • 基金资助:
    This work was supported by the National Natural Science Foundation of China(Nos.21706283 and 21776308),Beijing Talents Foundation(No.2017000020124G010),Science Foundation of China University of Petroleum,Beijing(No.2462017YJRC003),and the Joint Open Fund of Jiangsu Collaborative Innovation Center for Ecological Building Material and Environmental Protection Equipment and Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province(No.JH201812).

Exfoliated multi-layered graphene anode with the broadened delithiation voltage plateau below 0.5 V

Xinlong Maa, Xinyu Songb, Yushu Tanga, Enzuo Liuc, Chenggen Xua, Chuanlei Qia, Yun Lia, Jinsen Gaoa, Yongfeng Lia   

  1. a State Key Laboratory of Heavy Oil Processing,China University of Petroleum,Beijing 102249,China;
    b Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province,Yancheng Institute of Technology,Yancheng 224051,Jiangsu,China;
    c School of Materials Science and Engineering and Tianjin Key Laboratory of Composites and Functional Materials,Tianjin University,Tianjin 300072,China
  • Received:2020-01-21 Revised:2020-02-24 Online:2020-10-15 Published:2020-12-18
  • Contact: Yongfeng Li
  • Supported by:
    This work was supported by the National Natural Science Foundation of China(Nos.21706283 and 21776308),Beijing Talents Foundation(No.2017000020124G010),Science Foundation of China University of Petroleum,Beijing(No.2462017YJRC003),and the Joint Open Fund of Jiangsu Collaborative Innovation Center for Ecological Building Material and Environmental Protection Equipment and Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province(No.JH201812).

摘要: The commercial graphite (CG) is the conventional anode material for lithium ion batteries (LIBs) due to its low delithiation voltage plateau (below 0.5 V) and extraordinary durability.Nevertheless,the further promotion of energy density of LIBs is restricted by the limited capacity below 0.5 V of CG.Here,based on the supercritical CO2 exfoliation technique,the production of multi-layered graphene (MLG) is achieved from the pilot scale production line.The great merit of the exfoliated MLG anode is that the voltage plateau below 0.5 V is broadened obviously as compared to those of natural graphite and CG.Additionally,no obvious lithium dendrites are observed for MLG during the lithiation process.The large delithiation capacity under the low voltage plateau of MLG is mainly benefited from the combination of Li intercalation and boundary storage mechanism,which is further confirmed by the density functional theory calculations.The LiFePO4/MLG full cell can afford the satisfactory electrochemical property with respect to the capacity,energy density and ultralong cycling stability (90% capacity retention after 500 cycles at 2 C),significantly better than that of LiFePO4/CG.Besides,this developed technique not only dedicates to producing the high-performance anode for LIBs but also opens a door for the mass production of MLG in the industrial scale.

关键词: Multi-layered graphene, Supercritical CO2 exfoliation, Anode, Broadened delithiation voltage plateau, Intercalation and boundary storage

Abstract: The commercial graphite (CG) is the conventional anode material for lithium ion batteries (LIBs) due to its low delithiation voltage plateau (below 0.5 V) and extraordinary durability.Nevertheless,the further promotion of energy density of LIBs is restricted by the limited capacity below 0.5 V of CG.Here,based on the supercritical CO2 exfoliation technique,the production of multi-layered graphene (MLG) is achieved from the pilot scale production line.The great merit of the exfoliated MLG anode is that the voltage plateau below 0.5 V is broadened obviously as compared to those of natural graphite and CG.Additionally,no obvious lithium dendrites are observed for MLG during the lithiation process.The large delithiation capacity under the low voltage plateau of MLG is mainly benefited from the combination of Li intercalation and boundary storage mechanism,which is further confirmed by the density functional theory calculations.The LiFePO4/MLG full cell can afford the satisfactory electrochemical property with respect to the capacity,energy density and ultralong cycling stability (90% capacity retention after 500 cycles at 2 C),significantly better than that of LiFePO4/CG.Besides,this developed technique not only dedicates to producing the high-performance anode for LIBs but also opens a door for the mass production of MLG in the industrial scale.

Key words: Multi-layered graphene, Supercritical CO2 exfoliation, Anode, Broadened delithiation voltage plateau, Intercalation and boundary storage