A research team at the University of Central Florida has developed technology that could prevent electric vehicle fires, like those caused by saltwater flooding from Hurricane Ian.
The technology, an aqueous battery, replaces the volatile and highly flammable organic solvents found in electric vehicle Li-ion batteries with saltwater to create a battery that is safer, faster charging, just as powerful and won’t short circuit during flooding. The work is detailed in a new study in Nature Communications.
“During Hurricane Ian, a lot of electric cars caught fire after they were soaked in floodwater,” said Yang Yang, an Associate Professor in UCF’s NanoScience Technology Center who led the research. “That is because the saltwater corrodes the battery and causes a short circuit, which ignites the flammable solvents and other components. Our battery uses saltwater as an electrolyte, eliminating the highly volatile solvents.”
Also key to the battery’s design is its novel, nano-engineering that allows the battery to overcome limitations of previous aqueous batteries, such as slow charging times and poor stability.
Yang is an expert in developing materials for renewable energy devices such as batteries with improved safety. The UCF-designed battery is fast charging, reaching full charge in three minutes, compared to the hours it takes Li-ion batteries.
Previous aqueous battery designs have suffered from low energy output, instability, the growth of harmful metallic structures called dendrites on the negative electrode and corrosion.
By using saltwater as the battery’s liquid electrolyte, the UCF researchers were able to use naturally occurring metal ions found in the saltwater, such as sodium, potassium, calcium, and magnesium, to create a dual-cation battery that stores more energy. This implementation allowed them to overcome the sluggishness of previous single-cation aqueous battery designs.
To solve problems with instability, dendrite growth and corrosion, the researchers engineered a forest-like 3D zinc-copper anode containing a thin zinc-oxide protective layer on top.
The novel, nano-engineered surface, which looks like a birds-eye-view of a forest, allows the researchers to precisely control electrochemical reactions, thereby increasing the battery’s stability and quick charging ability. Furthermore, the zinc-oxide layer prevented dendritic growth of zinc, which was confirmed using optical microscopy.
“These batteries using the novel materials developed in my lab will remain safe even if they are used improperly or are flooded in saltwater,” Yang said. “Our work can help improve electric vehicle technology and continue to advance it as reliable and safe form of travel.”