• 文献标题:   Dense Graphene Monolith for High Volumetric Energy Density Li-S Batteries
  • 文献类型:   Article
  • 作  者:   LI H, TAO Y, ZHANG C, LIU DH, LUO JY, FAN WC, XU Y, LI YZ, YOU CH, PAN ZZ, YE MC, CHEN ZY, DONG Z, WANG DW, KANG FY, LU J, YANG QH
  • 作者关键词:   graphene monolith, inkbottlelike pore, lithiumpolysulfide batterie, polysulfide, volumetric performance
  • 出版物名称:   ADVANCED ENERGY MATERIALS
  • ISSN:   1614-6832 EI 1614-6840
  • 通讯作者地址:   Tianjin Univ
  • 被引频次:   29
  • DOI:   10.1002/aenm.201703438
  • 出版年:   2018

▎ 摘  要

Despite the outstanding gravimetric performance of lithium-sulfur (Li-S) batteries, their practical volumetric energy density is normally lower than that of lithium-ion batteries, mainly due to the low density of nanostructured sulfur as well as the porous carbon hosts. Here, a novel approach is developed to fabricate high-density graphene bulk materials with ink-bottle-like mesopores by phosphoric acid (H3PO4) activation. These pores can effectively confine the polysulfides due to their unique structure with a wide body and narrow neck, which shows only a 0.05% capacity fade per cycle for 500 cycles (75% capacity retention) for accommodating polysulfides. With a density of 1.16 g cm(-3), a hybrid cathode containing 54 wt% sulfur delivers a high volumetric capacity of 653 mA h cm(-3). As a result, a device-level volumetric energy density as high as 408 W h L-1 is achieved with a cathode thickness of 100 mu m. This is a periodic yet practical advance to improve the volumetric performance of Li-S batteries from a device perspective. This work suggests a design principle for the real use Li-S batteries although there is a long way ahead to bridge the gap between Li-S batteries and Li-ion batteries in volumetric performance.