Lithium-ion batteries get storage capacity upgrade from rust anodes

Researchers from Germany’s Saarland University and Austria’s University of Salzburg have developed a novel lithium-ion battery anode that incorporates iron oxide (rust) into microscopic, porous hollow carbon spheres. This innovative design aims to provide a more environmentally friendly alternative to conventional lithium-ion batteries, which typically rely on costly and toxic transition metals like nickel and cobalt. The carbon spheres, inspired by the layered structure of Mozartkugeln confections, are about 250 nanometers in diameter and feature a large surface area with finely dispersed iron nanoparticles embedded within their framework. A key finding of the study is that the battery’s storage capacity improves over time, reaching full capacity after approximately 300 charge-discharge cycles. This increase occurs because the metallic iron nanoparticles gradually react with oxygen to form iron oxide within the carbon spheres, a process described as progressive electrochemical activation. While the current research focuses on the anode material, further work is needed to accelerate this activation process and to pair the anode with a suitable cathode for