Researchers at the University of Maryland have invented a new water-based zinc battery that is safer than a traditional lithium-ion battery, but which doesn’t sacrifice power or usability. The team utilized elements of older zinc battery technology with novel water-in-salt electrolytes to create a battery that is not prone to catching fire. “Water-based batteries could be crucial to preventing fires in electronics, but their energy storage and capacity have been limited – until now,” said study first author Fei Wang in a statement. “For the first time, we have a battery that could compete with the lithium-ion batteries in energy density, but without the risk of explosion or fire.” Their work was recently published in the journal Nature Materials.
One of the new battery‘s improvements over traditional batteries is its ability to overcome irreversibility, the phenomenon in which the charge delivered by the battery at its intended voltage decreases with usage, through a technique that changes the structure of the positively charged zinc ions within the battery. In addition to the battery’s application in consumer goods, it also could prove invaluable in extreme conditions such as the deep ocean or outer space.
The saline aqueous nature of the zinc battery eliminates the need to replace evaporated water within the battery, a key challenge of traditional zinc batteries. “Existing zinc batteries are safe and relatively inexpensive to produce, but they aren’t perfect due to poor cycle life and low energy density,” said study co-author Chunsheng Wang in a statement. “We overcome these challenges by using a water-in-salt electrolyte.” The researchers believe that their invention and related discoveries could be applicable to a wide variety of energy technologies. “The significant discovery made in this work has touched the core problem of aqueous zinc batteries,” said study co-author Kang Xu in a statement, “and could impact other aqueous or non-aqueous multivalence cation chemistries that face similar challenges, such as magnesium and aluminum batteries.”
Images via John T. Consoli/University of Maryland