A team of researchers in China has used a high lithiophilic Mg-Li-Cu alloy to stabilize a Li metal anode. Due to the delocalization of electrons on the deposited lithium enhanced by Cu self-diffusion into Mg-Li alloy, the growth of lithium dendrites can be inhibited by the Mg-Li-Cu alloy. Moreover, the parasitic reactions with electrolyte can be avoided by the Mg-Li-Cu alloy anode.

In an open-access paper in the Journal of Magnesium and Alloys, the team reported that the symmetric battery life of Mg-Li-Cu alloy electrodes exceeds 9000 h at 1 mA cm−2 and 1 mAh cm−2. The full cell (LiFePO4 || Mg-Li-Cu) exhibits a specific capacity of 148.2 mAh g−1, with a capacity retention of 96.4%, at 1 C after 500 cycles.

The adsorption configuration (a, c) and charge density difference plot (b, d) of Li on Mg-Li (110) surface (a, b) and Mg-Li-Cu (110) surface (c, d), respectively. Areas of charge accumulation are shown in yellow while depletion is shown in light blue. Schematic illustration of Li deposition behavior on (e) bare Li, (f) Mg-Li and (g) Mg-Li-Cu, respectively. Li et al.