Substituting copolymeric poly(alkylenetetrasulfide) for elemental sulfur to diminish the shuttling effect of modified intermediate polysulfides for high-performance lithium–sulfur batteries

Poly(alkylenetetrasulfide) can be synthesized to replace sulfur in a chitosan-derived porous carbon (CPC) based composite cathode of lithium-sulfur batteries. Introducing a -CH2- or -CH2CH2- unit in-between the S-S bond of a polysulfide (e.g., Li2S4 → Li-S2-CH2-S-Li or Li-S-CH2CH2-S-Li) diminishes the adverse shuttling effect, proved by experimental tests and first-principle calculations.