Doubling the capacity of iron oxide-type cathodes for affordable Li-ion batteries

• A research group has demonstrated a high-energy lithium-ion (Li-ion) cathode, potentially paving the way for economical, risk-free as well as high-capacity Li-ion batteries.

Li-ion batteries are ubiquitous in electronic devices and also electrical vehicles, as well as will play a prominent role in charging a sustainable future. Yet Li-ion batteries count on transition metals such as cobalt and also nickel. And also supplies of these pricey materials are limited to a handful of countries. Creating transition metals from earth-abundant components is consequently an important task for researchers.

Olivine-type lithium-iron phosphates (LiFePO4) have revealed pledge in recent years as an affordable option. Yet their storage capacity is limited considering that the material counts on iron's single electron transfer, i.e., iron redox.

Due to this, the team checked out the antifluorite-type lithium-iron oxide (Li5FeO4). First reported on in 1999, Li5FeO4, has a theoretical capacity twice that of LiFePO4 since it includes an oxygen redox as well as an iron redox. But utilizing both the iron and also oxygen redox is tough to achieve.

To conquer this, the team employed a mechanochemical alloying approach to bring Li5FeO4 to a metastable phase. The fabricated metastable Li5FeO4 displayed iron and also oxygen redox, and also demonstrated double the capacity of LiFePO4.

" Our technique turned the theoretical into truth, and also sets us on a path to creating high-energy cathode materials," says Dr. Hiroaki Kobayashi, lead author of the paper and professor at Tohoku University's Institute of Multidisciplinary Research Study for Advanced Materials. "This will lead to economical, high-capacity Li-ion batteries based upon abundant materials."

The research study was carried out as a joint-research project between Tohoku University as well as the Nagoya Institute of Technology. Details were released in the journal Advanced Energy Materials on January 15, 2023.