Insights into the electrochemical performances of Bi anodes for Mg ion batteries using 25Mg solid state NMR spectroscopy

Abstract

Bi nanowires as anode materials for Mg ion batteries exhibit excellent electrochemical behaviour, forming Mg₃Bi₂; this is in part ascribed to the rapid Mg mobility between the two Mg sites of Mg₃Bi₂, as revealed by the ²⁵Mg NMR spectra of Mg₃Bi₂ formed electrochemically and via ball-milling. A mechanism involving hops into vacant Mg sites is proposed.