Mg-Ce-Mn Alloy Negative Electrode for Rechargeable Magnesium Batteries

Abstract The commercialization of rechargeable magnesium batteries is hindered by nonuniform Mg stripping/plating and severe side reactions of Mg negative electrode. Herein, a ternary Mg-Ce-Mn alloy with trace solid-solution elements is proposed as negative electrode. The refined grain size and Mg-philic surface increase the active sites and reduce the desolvation barrier, promoting uniform nucleation and enabling a uniform electric field distribution. Consequently, the Mg-Ce-Mn symmetric cell cycles stably for over 1590 h at 3 mA cm–2 and 3 mAh cm–2, and the Mg-Ce-Mn||Mo6S8 full cell delivers 74.37 mAh g–1 at 1 C with 92.6% capacity retention after 2200 cycles. This work not only provides insights into addressing the challenges associated with nonuniform Mg stripping/plating behavior but also contributes to improving both the electrochemical and mechanical formability of Mg negative electrodes.