Review and Perspectives on Advanced Binder Designs Incorporating Multifunctionalities for Lithium–Sulfur Batteries

Lithium–sulfur (Li–S) batteries have received paramount attention as a next-generation energy storage device due to their remarkably high specific capacity (1675 mAh g–1), energy density (2600 Wh kg–1), and cost-effectiveness compared to the forefront lithium-ion batteries. However, certain issues still hamper the smooth working of Li–S batteries, which need to be addressed to fill the gap between fundamental research and commercialization. Polymer binders, as an inevitable part of the cathode structure, play a vital role in upholding the structural robustness and firmness of the electrode. However, conventional binders like PVDF are not capable of effectively accommodating the large volume changes within the electrode, facilitating electronic/ionic conductivity, entrapping the soluble polysulfide intermediates, and enhancing polysulfide redox kinetics. Therefore, novel multifunctional binder designs are adopted in Li–S batteries to tackle the above-mentioned issues. This review summarizes the recent progress in this research area employing advanced multifunctional polymer binders in Li–S batteries. The action of the binder through various mechanisms is discussed in detail. The role of binder is given immense attention in the emerging field of various energy storage devices, including Li–S batteries, and, thus, here discussed as well.