
Magnesium batteries vie as lithium alternative
Hosted by the Helmholtz Institute Ulm (HIU) and Ulm Electrochemical Talks (UECT), the symposium looked at the latest state of research and to identify future scenarios. The presentations and posters at the symposium dealt with the topics electrolytes and additives, electrode interfaces, cathodes, anodes, modeling and systems.
Compared to lithium, magnesium may release and absorb two electrons, making it a very interesting material for battery research into stationary energy storage, for example in wind turbines or solar panels. Magnesium batteries are currently the most often researched candidates for lithium-free alternatives in the field of “high-voltage batteries” – not least because some automobile manufacturers invest in the research of magnesium batteries.
Magnesium is less reactive and so less dangerous for high density batteries, and during charging no dendrites grow with magnesium, which represents the main challenge to security in the use of lithium metal anodes. It is also cheaper to produce because it reacts less rapidly with air as lithium metal. Magnesium is available in large quantities, for instance in the form of rock dolomite, which results in lower prices.
Engineers at Toyota’s Research Institute of North America (TRINA) back in May announced a new electrolyte for magnesium batteries from research into hydrogen fuel cells. “We were able to take a material that was only used in hydrogen storage and we made it practical and very competitive for magnesium battery chemistry,” said researcher Rana Mohtadi.
Instead of using a chloride-based elctrolyte that can be corrosive, the new design concept uses boron cluster anions for the first halogen-free, simple-type magnesium salt that is compatible with the magnesium metal and is more stable that other electrolytes. This allows high-voltage cathodes to be used for a typical coin cell, marking a turning point in the research and development of practical rechargeable magnesium batteries, say the researchers.
HUI was founded in January of 2011 by the Karlsruhe Institute of Technology (KIT) and is a member of the Helmholtz Association, Germany’s largest scientific organization. It works closely with organizations such as the University of Ulm, the German Aerospace Center (DLR), and the Centre for Solar Energy and Hydrogen Research Baden-Württemberg (ZSW).
