Facile synthesis of porous Co3O4 nanoflakes as an interlayer for high performance lithium-sulfur batteries

Dalton Trans. 2020 May 7;49(17):5677-5683. doi: 10.1039/d0dt00429d. Epub 2020 Apr 15.

Abstract

The "shuttle effect" of long-chain polysulfides and the low conductivity of elemental sulfur lead to the inferior cycling stability of lithium-sulfur batteries and imped their practical applications. Herein, Co3O4 nanoflakes with uniform macro pores distribution were synthesized via facile oil bath and calcination methods. Coupled with super P and coated on common polypropylene separators, they were expected to hinder the migration of lithium polysulfides (LiPSs) and accelerate the redox kinetics of polysulfides. Coin cells assembled with the Co3O4-super P interlayer exhibited a capacity of 760 mA h g-1 at 1 C, maintained 598 mA h g-1 after 350 cycles, and the decay rate of discharge capacity was only about 0.062% per cycle. Such high performance can be attributed to the synergistic effects between polar Co3O4 and conductive super P. The facile fabrication method and high performance make the Co3O4-super P interlayer a feasible material to apply in lithium-sulfur batteries.