Bismuth chloride@mesocellular carbon foam nanocomposite cathode materials for rechargeable chloride ion batteries

Chloride ion batteries (CIB) are considered to be one of the most promising energy storage devices. As cathode materials for CIBs, metal chlorides have many advantages, such as high theoretical energy density, abundant elemental resources and ideal discharge voltage plateau. However, the dissolution and huge volume change of metal chlorides during cycling lead to considerable short lifespan, which limits their potential application for CIBs. Herein, the bismuth chloride nanocrystal is confined in mesocellular carbon foam matrix by a new vacuum impregnation approach. The mesocellular carbon foam with large interconnected pores (15.7 or 23.2 nm) may buffer the large volume variation of bismuth chloride during charge and discharge, giving rise to significantly enhanced electrochemical performance. The as-prepared bismuth chloride@mesocellular carbon foam cathode delivered an initial discharge capacity of 298 mAh/g and a reversible capacity of 91 mAh/g after 60 cycles. In contrast, the pure bismuth chloride cathode almost cannot discharge after 30 cycles. This is the first report that the metal chloride cathode can achieve a prolonged cycling in CIBs. (c) 2021 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.

Automated summary

Chloride ion batteries (CIBs) are a promising energy storage device, but the dissolution and volume change of metal chlorides as cathode materials limit their application. This study presents a new method to confine bismuth chloride nanocrystals in a mesocellular carbon foam matrix, resulting in improved electrochemical performance and prolonged cycling for the metal chloride cathode.