Discharging a Li-S battery with ultra-high sulphur content cathode using a redox mediator.

Lithium-sulphur batteries are under intense research due to the high specific capacity and low cost. However, several problems limit their commercialization. One of them is the insulating nature of sulphur, which necessitates a large amount of conductive agent and binder in the cathode, reducing the effective sulphur load as well as the energy density.

Enhancement of cycle performance of Li-S batteries by redistribution of sulfur.

A practically available strategy is employed to improve the cycle life of lithium-sulfur batteries. The simple process of activation cycling at the polysulfide dissolution region leads to the partial dissolution of polysulfides and the redistribution of sulfur on the electrode. After 50 cycles, the modified activation-cycled sulfur cathode exhibits a capacity that is roughly double that of a cathode without activation cycling.

Inverse Vulcanization of Elemental Sulfur to Prepare Polymeric Electrode Materials for Li-S Batteries.

Sulfur-rich copolymers based on poly(sulfur-1,3-diisopropenylbenzene) (poly(S--DIB)) were synthesized via inverse vulcanization to create cathode materials for lithium-sulfur battery applications. These materials exhibit enhanced capacity retention (1005 mAh/g at 100 cycles) and battery lifetimes over 500 cycles at a C/10 rate. These poly(S--DIB) copolymers represent a new class of polymeric electrode materials that exhibit one of the highest charge capacities reported, particularly after extended charge-discharge cycling in Li-S batteries.