Experts at a leading US university believe best in class lithium-ion cells may face stiff competition from aqueous alternatives.
While the idea of using fuel cells designed around liquids seems counter-intuitive given the problematic relationship between water and electricity, aqueous batteries, which use water-based electrolytes, are considered safe, reliable and affordable.
While lithium-ion batteries are used in everything from mobile phones to electric vehicles (EVs), they come with significant drawbacks. Not least the price of production and development, including high environmental cost linked to mining prerequisite raw materials, and instability in certain conditions which can lead to cells catching fire or even exploding.
Currently, commercial aqueous batteries lack the energy density and power life to pose a serious threat to lithium-ion, so they are not ready to be considered for large applications like grid storage or transportation. Nevertheless, breakthroughs in materials science and chemistry mean new opportunities are rapidly appearing on the horizon for more advanced forms of this technology.
‘The idea is to develop advanced aqueous batteries that can combine better safety and higher voltage,’ said Yan Yao, Hugh Roy and Lillie Cranz Cullen Distinguished Professor of Electrical and Computer Engineering and principal investigator at the Texas Center for Superconductivity at the University of Houston, who has been leading research on energy storage materials and devices for around a decade.
‘Our review is extensive in scope because we wanted to paint a big picture on the landscape of aqueous batteries,’ Liang said. ‘If we don’t understand the overall picture, we can’t know where the next opportunity will be.’
If realised, there are several major benefits from switching to aqueous batteries, including widely available, low-cost raw materials, minimal requirements for controlled manufacturing environments, reduced fire risk, simple fabrication and high power potential. Liang and his cohorts believe this area of research is on the cusp of offering the next major breakthrough in batteries, although recent advancements in lithium-ion designs continue to push the technology forward — find out more about that here.
Image: Peter Olexa