Uniform honeycomb-like microspheres constructed with titanium nitride to confine polysulfides for extremely stable lithium-sulfur batteries

Lithium-sulfur batteries are considered the most promising next-generation electrochemical energy storage devices due to their high theoretical energy density. However, their practical application is hindered by the severe shuttle effect of polysulfides and the low conductivity of sulfur cathode. Herein, we design a titanium nitride host with a three-dimensional honeycomb-like structure via a spray drying method, which has the advantages of metallic conductivity and ultrafast anchoring to realize efficient adsorption and conversion of polysulfide. The honeycomb-like architecture can shorten the diffusion path of lithium ions, and buffer the volume change of sulfur, which can improve reaction kinetics and maintain the stability of the material structure. As a result, the sulfur cathode based on titanium nitride host exhibits an excellent cycling performance with a stable capacity of 650.4 mAh g−1 within 500 cycles at 100 mA g−1. The excellent performance shows the importance of designing cathode materials with reasonable structures in lithium sulfur batteries.