An ab initio study for electrochemistry: Superconductor layer FeAs as a novel anode material for lithium ion batteries

A potential application of Fe-based layers (FeAs, FeSe) as a new promising anode material was proposed in the fields of second batteries by systematic first-principles calculations. The calculation results indicate that those conventional superconductor layers, such as FeAs, can deliver a theoretical capacity of 1 044 mAh/g, three times higher than that of the graphite-type anode. Further dynamic investigation suggests that Li/FeAs experiences a conversion reaction forming Li3As and Fe through a two-step reaction in the first cycle. In the following cycles, Li-ion reversibly intercalates into arsenic at 077 V or deintercalates from Li3As at 116 V, which is similar to the lithiation/de-lithiation mechanism of silicon anode materials. Based on their high energy density and good dynamic mechanism, these superconductor layers are thought to be a complex functional electrode candidates for future large-energy batteries systems.