Emerging applications of atomic layer deposition for lithium-sulfur and sodium-sulfur batteries

Abstract Lithium-sulfur (Li–S) and sodium-sulfur (Na–S) batteries are the promising energy storage systems of next-generation because of their high theoretical specific energy, abundant storage of sulfur, and long cycle life. However, both of them are suffering the low conductivity, volume expansion of cathode, corrosion of Li/Na anode by the electrolyte, shuttle effect of polysulfides, and dendrites formation of Li/Na metal anode. The new technology of atomic layer deposition (ALD) has shown great potential in Li-ion and Na-ion batteries due to the outstanding conformal deposition, digitized and accurate film thickness, and the mild low-temperature growth on complex substrates, such as mesoporous materials. Inspired by these benefits, recently, more and more studies successfully employed ALD strategy to fabricate or modify cathodes, anodes, interlayers, and all-solid-state electrolytes with precisely atomic level conformal films to improve their conductivity, stability, and mechanical properties for the high electrochemical performance of Li–S and Na–S batteries. To our knowledge, this is the first review to systematically summarize the most recent advances of ALD for both Li–S and Na–S batteries applications. Especially, various functions of the ALD technique in Li–S and Na–S batteries have been presented and fully discussed with classical examples. Further, the mechanism, advantages, and future development of ALD are also proposed and discussed.