石墨烯导电添加剂在锂离子电池正极中的应用

Application of graphene conductive additives in cathodes of lithium ion batteries

石墨烯的高电导率、大比表面积、优异的化学稳定性和力学性能,有利于其在锂离子电池正极导电剂方面的应用。与炭黑、石墨和碳纳米管等传统导电剂相比,石墨烯“至柔至薄”的独特二维结构能与活性物质实现“面-点”接触,实现电极上的“长程”导电,保证电子的快速传输。本文回顾了近年来石墨烯基导电剂在基础研究和产业化应用方面的进展,认为将石墨烯与炭黑或/和碳纳米管复配形成复合导电剂,能构建包含“面-点”、“点-点”、“线-点”的多元导电网络,兼顾“长程”和“短程”导电,有利于提高电极的导电性,改善其电化学性能,同时兼顾相对较低的成本,应用前景广阔。本文还对当前石墨烯基导电剂面临的问题及未来的发展方向做出了展望。

The high conductivity,high specific surface area,and excellent chemical stability and mechanical properties of graphene make it attractive as a conductive additive in cathodes for lithiumion batteries(LIBs).Unlike conventional additives,such as carbon black,graphite,and carbon nanotubes(CNTs),flexible ultrathin graphene with a unique two-dimensional structure provides“plane-to-point”contact with the active materials,realizing long-range conduction while promoting fast electron transportation in the electrode.In this study,recent progress in graphene conductive additives used for cathodes in LIBs in fundamental research and industrial applications is reviewed.The combination of graphene with carbon black and/or CNTs as hybrid conductive additives can create a vast conductive network,including the“plane-to-point,”“point-to-point,”and“line-to-point”conducting modes;thus,this combination of long-range and short-range conduction increases the overall electrode conductivity.The obtained improvement in electrochemical performance not only affects the efficiency but also reduces the overall electrode production cost,realizing myriad potential applications in the industrial sector.Finally,the challenges and future prospects of graphene conductive additives are outlined.