Protected lithium anode with porous Al₂O₃layer for lithium–sulfur battery

Abstract

A lithium anode protected with a porous Al2O3layer is beneficial for improving the cycle stability and capacity retention of a lithium–sulfur battery.

Structural Design of Lithium–Sulfur Batteries: From Fundamental Research to Practical Application

“…A 0.23 mg cm −2 Al 2 O 3 coating layer was found to be insufficient and could not form a complete physical barrier to effectively restrict PS dissolution, while electrolyte penetration and Li + diffusion were blocked by the 0.73 mg cm −2 Al 2 O 3 coating layer. As a result, an optimized 0.58 mg cm −2 Al 2 O 3 coating layer was obtained and achieved the best battery performance, which enabled a capacity retention of 70% from the initial capacity of 1215 mA h g −1 at 160 mA g −1 after 50 cycles [303]. As another nanoscale coating technique, ALD is well known for enabling uniform thin-film deposition on substrates with high-aspect-ratio topography as well as controlling the thickness of thin films at atomic scale [305,306].…”

“…One of the most effective and widely used methods to protect the lithium metal is to coat a protective layer on the surface to act as a physical barrier to against lithium dendrite formation and dissolved polysulfides [202,[300][301][302][303][304]. Porous Al 2 O 3 with 0.23, 0.58 and 0.73 mg cm −2 coating layers were fabricated to suppress the side reactions between the Li anode and PS species by using a spin-coating method.…”

Recent development of metal compound applications in lithium–sulphur batteries

“…11 It was firstly applied as the additive in the sulfur cathode to improve the electrochemical performances of Li-S batteries. 100,101 Later Al 2 O 3 was applied as the coating layer on both sulfur cathodes [102][103][104] and separators, 12,73,105 which has proved to be effective in enhancing the cycle stability of Li-S batteries.…”

“…11 The Al 2 O 3 protective layer can restrict the side reactions between soluble lithium polysulphides and the lithium anode through a combination of physical separation and chemical adsorption by the Al 2 O 3 layer, which can alleviate lithium corrosion due to polysulfide attack.…”

“…3,6 Therefore multiple and combined strategies, such as developing new electrolyte and binder, 9,10 protecting the anode, 11 modifying the separator 12 and the sulfur cathode 13,14 are used to solve the above problems. Among which, using the nanostructured materials to modify the sulfur cathode are most popular.…”