Sulfur-containing polydimethylsiloxane polymer enables stable lithium metal anodes for lithium sulfur batteries at room and low temperature

Lithium-sulfur (Li-S) battery has garnered worldwide attention as the promising energy storage devices, owing to its significant energy density. Nevertheless, safety apprehensions and deficient cycling constancy of lithium (Li) anode, arising from unbridled Li dendrite growth, have conspicuously impeded its commercialization. Herein, we propose a sulfur-containing polydimethylsiloxane (PDMS-ALA) polymer, consisting of PDMS moieties and -S-S- moieties to enhance the stability of Li metal anodes. The PDMS-ALA polymer facilitates to form a stable hybrid solid electrolyte interphase (SEI) layer, which functions as a robust protective layer and ionic conductor, guaranteeing uniform Li-ion flux and deposition while further restraining Li dendrite growth. Consequently, both the PDMS-ALA-modified symmetric Li-Li cells and asymmetric Li-Cu cells demonstrated a more stable and prolonged Li stripping/plating process with lower overpotential compared to the pristine cells. More importantly, the PDMS-ALA-modified Li-S cells manifest superior electrochemical performance at both room temperature and low temperatures in comparison to the pristine system. Therefore, utilizing PDMS-ALA to stabilize the Li anode represents an effective solution to the challenges associated with anodes, facilitating the practical application and commercial viability of lithium metal batteries.