Suppressing Chemical Corrosions of Lithium Metal Anodes

The lithium metal anode is essential for next-generation high-energy-density rechargeable Li-metal batteries. Although extensive studies have been performed to prolong the cycle life of Li-metal batteries, the calendar life, which associates with the chemical corrosion of Li metal in liquid electrolytes, has not been quantitatively understood. Here, by combing the titration gas chromatography method and cryogenic focused ion beam, a quantitative relationship between the chemical corrosion rate and electrochemically deposited Li morphology in various liquid electrolyte systems is established. It has been identified that the corrosion rate is dominated by the porosity of the deposited Li. The larger the porosity of deposited Li has, the faster the corrosion rate will be. Strategies to mitigate the chemical corrosion on Li thus to extend the calendar life of Li-metal batteries are further proposed. By strictly controlling the stacking pressure during Li plating, Li deposits with ultra-low porosity can be achieved, suppressing the corrosion rate to 0.08 +/- 0.16%/day compared with 1.71 +/- 0.19%/day of the high-porosity Li.

Automated summary

The research establishes a quantitative relationship between the chemical corrosion rate and the morphology of electrochemically deposited Li in various liquid electrolyte systems, finding that the corrosion rate is primarily influenced by the porosity of the deposited Li. By strictly controlling the stacking pressure during Li plating, ultra-low porosity Li deposits can be achieved, leading to a significant reduction in corrosion rate.