If I say rechargeable batteries, most people think immediately about Li-ion batteries as the most successful achievement in this field. However, some issues related to safety, energy density and price are now forcing Li-ion battery research through big challenges, highlighting Mg batteries as a promising alternative technology for energy storage and conversion.
In their recent PCCP Perspective, Doron Aurbach and co-authors provide a closer look at Mg rechargeable batteries and guide the reader through 23 years of research since the first breakthrough in 1990 by Gregory et al. Gregory’s group demonstrated that Mg organo-borate moieties in solution, such as Mg(BBu2Ph2)2 in THF, allow magnesium to be deposited/dissolved successfully in a reversible process, despite the absence of highly reducing Grignard reagents.
This work led to a 2nd breakthrough in 2000 by Aurbach et al. who developed new electrolyte solutions comprised of ethereal solvents and complexes of the Mg(AlCl4-nRn)2 type (R = alkyl or aryl groups), with 100% reversibility of Mg deposition and anodic stability of 2.1 V vs. Mg.
Some companies, including Sony, LG and Toyota, already have prototypes of high energy density Mg rechargeable batteries with 2-3 V anodic stability. Compatibility needs to be enhanced in order to allow further developments of efficient rechargeable batteries.
by Martina Congiu
Interested in a better understanding about this field? Read more from the Perspective article: