Electrochemical Investigations of Sulfur-Decorated Organic Materials as Cathodes for Alkali Batteries

However, Li/Na-S batteries still face big challenges, such as limited cycle life, poor conductivity, large volume changes, and “shuttle effect” caused by the high solubility of Li/Na-polysulfides. Herein, novel organosulfur-containing materials, i.e., bis(4-hydroxy-2,2,6,6-tetramethylpiperidin-1-yl)disulfide (BiTEMPS-OH) and 2,4-thiophene/arene copolymer (TAC) are proposed as cathode materials for Li and Na batteries.

BiTEMPS-OH shows an initial discharge/charge capacity of 353/192 mAh g-1 and a capacity of 62 mAh g-1 after 200 cycles at 100 mA g-1 in ether-based Li-ion electrolyte. Meanwhile, TAC has an initial discharge/charge capacity of 270/248 mAh g-1 and better cycling performance (106 mAh g-1 after 200 cycles) than BiTEMPS-OH in the same electrolyte. However, the rate capability of TAC is limited by the slow diffusion of Li-ions.