Researchers at Tohoku University have made a advancement in battery technology by developing a novel cathode material for rechargeable magnesium batteries (RMBs) that enables efficient charging and discharging even at low temperatures. This innovative material, leveraging an enhanced rock-salt structure, promises to usher in a new era of energy storage solutions that are more affordable, safer, and higher in capacity.
The study showcases a considerable improvement in magnesium (Mg) diffusion within a rock-salt structure, a critical advancement since the denseness of atoms in this configuration had previously impeded Mg migration. By introducing a strategic mixture of seven different metallic elements, the research team created a crystal structure abundant in stable cation vacancies, facilitating easier Mg insertion and extraction.
This represents the first utilization of rocksalt oxide as a cathode material for RMBs. The high-entropy strategy employed by the researchers allowed the cation defects to activate the rocksalt oxide cathode.
The development also addresses a key limitation of RMBs—the difficulty of Mg transport within solid materials. Until now, high temperatures were necessary to enhance Mg mobility in conventional cathode materials, such as those with a spinel structure. However, the material unveiled by Tohoku University researchers operates efficiently at just 90°C, demonstrating a significant reduction in the required operating temperature.
