Lithium-sulfur (Li–S) batteries are among the most promising candidates for the next-generation rechargeable batteries due to their high energy density, cost-effectiveness, environmental friendliness and being on the verge of commercialization. However, considering the cathode part, low conductivity of sulfur, large volume expansion, dissolution of polysulfides in the electrolyte and their unfavorable shuttle behavior lead to low cell capacity and poor cycle life. More importantly, the high flammability of sulfur causes safety concerns that might hinder the large-scale application of lithium-sulfur batteries in electric vehicles, especially in tropical countries. Herein, we report a covalently linked sulfur (∼83% w/w) flame retarding sustainable copolymer as a suitable and safe cathode material for the practical application of Li–S batteries in tropical region. A remarkable intrinsic flame-retardant property with appreciable specific capacity and excellent capacity retention provide an alternative strategy for designing cathode materials for safe and sustainable Li–S batteries.

锂硫（Li–S）电池由于其高能量密度，成本效益，环境友好性以及处于商业化的边缘而成为下一代可充电电池最有希望的候选者之一。然而，考虑到阴极部分，硫的低电导率，大的体积膨胀，多硫化物在电解质中的溶解及其不利的穿梭行为导致低的电池容量和较差的循环寿命。更重要的是，硫的高度可燃性引起安全隐患，这可能会阻碍锂硫电池在电动汽车中的大规模应用，尤其是在热带国家。在这里 我们报道了一种共价键连接的硫（约83％w / w）阻燃可持续共聚物，作为在热带地区锂锂电池实际应用的合适和安全的阴极材料。具有显着的固有阻燃性能，明显的比容量和出色的容量保持能力，为设计安全可持续的Li-S电池正极材料提供了另一种策略。