Rechargeable Li–S batteries using Li metal as the anode and S as the cathode-active material are attractive energy storage candidates because the couple offers high specific capacities and possesses marketing advantages such as the light weight of Li and low cost of S. However, the commercialization of Li–S batteries remains hindered by several technical hurdles of both the S cathode and Li anode. The multistep electrochemical reactions of the S cathode involve various Li polysulfide intermediates (Li₂S_n, 3 ≤ n ≤ 8), some of which are highly soluble in aprotic organic electrolytes. The diffusion of these soluble polysulfides to the Li anode, also known as the polysulfide-shuttling effect, causes a series of problems including self-discharge, loss of active material, and corrosion of the Li anode. Meanwhile, metallic Li anodes are susceptible to the accumulation of dendritic Li deposits on their surfaces because of uneven Li-ion transport on the electrode surface during repeated charge–discharge cycles. This detrimental accumulation can cause low Columbic efficiency and even a short circuit, triggering thermal runaway and even battery explosions.

 Although the use of artificial coatings or membranes on Li anode surface has been suggested as a promising approach for suppressing Li dendrite formation, no previous study has simultaneously addressed Li dendrite formation and polysulfide-shuttling. In Li–S batteries, lithium nitrite (LiNO₃) has been widely used as an electrolyte additive for maintaining stable anode performance by inhibiting the reactions between polysulfides and the Li surface. However, the long-term feasibility of LiNO₃ is limited by its continuous consumption during battery operation. In this presentation, we report the successful development of a cation-selective and dimension-stable coating that can simultaneously suppress Li dendrite and polysulfide shuttling on the Li anode surface