硫正极中硝酸盐和黏结剂的种类对锂硫电池性能的影响

Effects of Different Kinds of Nitrates and Binders in Sulfur Electrodes on the Performance of Lithium-Sulfur Batteries

系统研究了正极中使用不同种类的硝酸盐和黏结剂对锂硫电池电化学性能的影响。通过对比锂硫电池的循环性能和库伦效率,发现以硝酸镁为正极添加剂的锂硫电池的库伦效率最高,且其最适合的质量分数为10%。在研究硫正极中硝酸盐和黏结剂的协同效应对锂硫电池电性能的影响时,发现使用β-环糊精聚合物(β-CDp)黏结剂的锂硫电池电化学性能最好。在此基础上,使用含硝酸锂的电解液可进一步提高了锂硫电池库伦效率(>98%),说明硫正极中的硝酸镁和黏结剂以及电解液中的硝酸锂之间有协同作用,可共同抑制穿梭效应,有助于进一步提高锂硫电池的放电比容量和库伦效率。

The effects of different kinds of nitrates and binders on the electrochemical performance of lithium sulfur batteries were systematically studied.By comparing the cycle performance and coulombic efficiency of lithium-sulfur battery,it was found that the lithium-sulfur battery using magnesium nitrate as the sulfur electrode additive has the highest coulomb efficiency.And the most suitable addition amount of magnesium nitrate is 10%.In investigating the influence of the synergistic effect of nitrates and binders in sulfur electrodes on the electrochemical performance of lithium-sulfur batteries,it was found that the lithium-sulfur battery using theβ-cyclodextrin polymer(β-CDp)binder delivered the best electrochemical performance.On this basis,by using the electrolyte containing lithium nitrate,the coulombic efficiency of lithium-sulfur batteries was further improved(>98%),indicating that there is a synergistic effect among the magnesium nitrate,theβ-CDp binder in the sulfur cathode and the lithium nitrate in the electrolyte,which could suppress the shuttle effect of polysulfides and further improve the discharge capacity and coulombic efficiency of lithium-sulfur batteries.