A low-cost and high-performance rechargeable magnesium battery based on povidone iodine cathode

Rechargeable magnesium battery is a potential candidate for large-scale energy storage applications owing to the high natural abundance and dendrite-free features of the magnesium metal anode, but exploration of highcapacity cathode is hindering the development. In the present study, a high-performance rechargeable magnesium battery is constructed based on a low-cost cathode of povidone iodine, which is widely used as medical disinfector. The electrochemically active iodine is anchored with the polyvinylpyrrolidone host with chemical interaction, which is stronger than the physical adsorption with carbon materials. The povidone iodine cathode exhibits a high reversible magnesium storage capacity (200 mAh g-1 based on I element and 80 mAh g-1 based on PVPI), an outstanding rate capability (70 mAh g-1 at 1600 mA g-1) and a remarkable cycling durability (0.18% capacity decay per cycle). A mechanism investigation demonstrates reversible magnesium storage reaction of PVP-I3-/PVP-I-. The chemical interaction of iodine with PVP effectively eliminates the shuttle effect, enhances the coulombic efficiency and alleviates the self discharge. The present work provides a low cost cathode for rechargeable magnesium batteries, and the strategy herein delivers insights for the performance enhancement of battery systems embarrassed by shuttle effect.

Automated summary

In this study, a high-performance rechargeable magnesium battery was developed using low-cost povidone iodine as the cathode material. The povidone iodine cathode demonstrated high reversible magnesium storage capacity, outstanding rate capability, and remarkable cycling durability. The chemical interaction of iodine with the host material effectively improved battery performance and eliminated the shuttle effect.