The direct reaction of polysulfide species with the Li metal anode causes several issues in the performance of lithium-sulfur batteries, from poor capacity utilization and fast capacity fade to poor Coulombic efficiency. Nevertheless, several reports indicate formation of favorable lithium SEI when allowing for its contact with polysulfides. With cycling tests, impedance spectroscopy measurements and morphology investigation, we have confirmed the beneficial effect of polysulfides on lithium metal stripping and deposition even without LiNO₃, which is usually added. Most importantly, highly concentrated catholytes, which are closer to the saturated solutions encountered in lean electrolyte-to-sulfur ratios, were tested. In the 1 M Li₂S₈ catholyte solution, its effect produced Li electrodes without dendritic growth, but rather a wrinkled surface. To circumvent the issue of viscosity in such solutions, pre-treatment in polysulfide solutions was also tested. The performance of such electrodes showed an increase in cycle life and lower overpotentials, although dendritic growth could not be fully avoided. In order to better understand the effect of pre-treatment on transport/reaction mechanism in Li electrode, a detailed analysis of selected impedance spectra is carried out using physics-based transmission line modelling (TLM).

多硫化物与锂金属阳极的直接反应会导致锂硫电池性能出现若干问题，从容量利用率低，容量衰减快到库仑效率差。然而，一些报道表明，当它与多硫化物接触时，会形成有利的锂SEI。通过循环测试，阻抗谱测量和形态研究，我们已经确认了多硫化物对锂金属的剥离和沉积的有益作用，即使通常不添加LiNO ₃。最重要的是，对高浓度的阴极电解液进行了测试，该电解液更接近以稀薄的电解液与硫的比率遇到的饱和溶液。在1 M Li ₂ S _8中阴极溶液，其作用产生的Li电极没有树枝状生长，而是表面起皱。为了避免这种溶液中的粘度问题，还测试了在多硫化物溶液中的预处理。尽管不能完全避免树枝状生长，但是这种电极的性能显示出循环寿命的增加和较低的过电位。为了更好地了解预处理对锂电极中传输/反应机理的影响，使用基于物理的传输线建模（TLM）对选定的阻抗谱进行了详细分析。