• 文献标题:   Graphene/PVDF Composites for Ni-rich Oxide Cathodes toward High-Energy Density Li-ion Batteries
  • 文献类型:   Article
  • 作  者:   PARK CW, LEE JH, SEO JK, RAN WTA, WHANG D, HWANG SM, KIM YJ
  • 作者关键词:   lithiumion batterie, nirich cathode, graphene, pvdf, electrode density, scanning probe microscopy
  • 出版物名称:   MATERIALS
  • ISSN:  
  • 通讯作者地址:  
  • 被引频次:   4
  • DOI:   10.3390/ma14092271
  • 出版年:   2021

▎ 摘  要

Li-ion batteries (LIBs) employ porous, composite-type electrodes, where few weight percentages of carbonaceous conducting agents and polymeric binders are required to bestow electrodes with electrical conductivity and mechanical robustness. However, the use of such inactive materials has limited enhancements of battery performance in terms of energy density and safety. In this study, we introduced graphene/polyvinylidene fluoride (Gr/PVdF) composites in Ni-rich oxide cathodes for LIBs, replacing conventional conducting agents, carbon black (CB) nanoparticles. By using Gr/PVdF suspensions, we fabricated highly dense LiNi0.85Co0.15Al0.05O2 (NCA) cathodes having a uniform distribution of conductive Gr sheets without CB nanoparticles, which was confirmed by scanning spreading resistance microscopy mode using atomic force microscopy. At a high content of 99 wt.% NCA, good cycling stability was shown with significantly improved areal capacity (Q(areal)) and volumetric capacity (Q(vol)), relative to the CB/PVdF-containing NCA electrode with a commercial-level of electrode parameters. The NCA electrodes using 1 wt.% Gr/PVdF (0.9:0.1) delivered a high Q(areal) of similar to 3.7 mAh cm(-2) (similar to 19% increment) and a high Q(vol) of similar to 774 mAh cm(-3) (similar to 18% increment) at a current rate of 0.2 C, as compared to the conventional NCA electrode. Our results suggest a viable strategy for superseding conventional conducting agents (CB) and improving the electrochemical performance of Ni-rich cathodes for advanced LIBs.