Physical characteristics of nickel thin-films and nickel thin-film foams as Li-air batteries anode and cathode current collectors

Abstract

Lithium-air batteries (LABs) are in the research and development stage between 2020 and 2030 as the future of lithium-ion batteries, and knowledge about their components provides the necessary data for commercializing. Current research investigates the physical characteristics of nickel (Ni) thin-films and Ni thin-film foams as anode and cathode current collectors, respectively, for LABs using the molecular dynamics simulation method. The obtained results provide helpful theoretical guidance for researchers to understand the physical attributes of current collectors and the interfacial interaction of air and electrolyte with cathode current collectors. Results indicate that the maximum service temperature of Ni thin-films and their foams with a 2.82–5.63 nm thickness equals 1200 and 1088 K, respectively, because the physical characteristics change significantly after these temperatures. Evaluation of the mechanical properties of Ni thin-films and their foams show that the mechanical attributes of these materials are in the acceptable region of current collectors. Therefore, Ni thin-films and their foams provide the required thermal and mechanical characteristics as anode and cathode current collectors, respectively. However, interfacial interaction between Ni thin-film foams with air and (CH3)2SO/LiPF6 non-aqueous electrolyte reveals that the presence of oxygen selective membrane is necessary for LABs cells. This membrane must not only block the flow of N2 and H2O toward the battery but also must impede the leakage of electrolytes. In addition, results depict that Ni thin-film foams have suitable applications as cathode current collectors for Li-N2 batteries due to more permeation depth of N2 molecules in comparison with other air molecules.