An encapsulation–reduction–catalysis confined all-in-one microcapsule for lithium–sulfur batteries displaying a high capacity and stable temperature tolerance characteristics

Developing emerging host materials for constructing high energy-density lithium–sulfur (Li–S) has received extensive attention. Herein, we develop a carbon nanotube (CNT)/S-infilled all-in-one microcapsule for Li–S batteries by catalytically growing CNTs using reduced Co3O4 nanoboxes inside amicrocapsule. The encapsulation of Co3O4 nanoboxes into the microcapsule is achieved by using an oil-in-water emulsion. In the all-in-one microcapsule, the CNTs improve the conductivity, the microcapsule shell reduces the loss of polysulfides during cycling, and the void inside the microcapsuleefficiently accommodates the volumetric change of sulfur. A Li–S battery based on the all-in-one microcapsule exhibits a high capacity of 1010 mA h g1 after 250 cycles and a coulombic efficiency of E99.8%. Moreover, the battery displays stable performance when cycling at temperatures of 5 1C and45 1C, which indicates its good potential for practical applications.