A labyrinth-like network electrode design for lithium-sulfur batteries

The volume expansion of sulfur and the dissolution of polysulfides into the electrolyte are the key issues to be solved in the development of lithium-sulfur batteries. In this work, a labyrinth electrode material design is presented to overcome these difficulties in lithium-sulfur batteries. The shell of NiO-Co3O4 hollow spheres as the wall to prevent the polysulfide dissolution cross-links into a labyrinth network as a sulfur host. The 3D labyrinth network not only provides enough inner space to load sulfur but also adapts to its large volume expansion during lithiation and delithiation. In addition, the polar NiO-Co3O4 shells can promote the chemical adsorption of polysulfides, while NiO-Co3O4 shells can promote the conversion of polysulfides into Li2S. With this unique design, the 3D labyrinth-like NiO-Co3O4@S electrode presents a good electrochemical performance, delivering high capacity with a stable cycling life of up to 200 cycles at 1C and the attenuation rate of each cycle is only 0.1%.