Electric vehicle (EV) naysayers frequently point to the unholy trinity of infrastructure, range, and price. Even if you’re an affluent city dweller with access to endless outlets, charge times still require anywhere from 15 minutes to 12 hours. That factor turns away many would-be EV adopters, but researchers at MIT may have found a solution to that charging conundrum.
In a paper published by MIT’s (Massachusetts Institute of Technology) Donald Sadoway (along with 15 other authors from Peking University, Yunnan University, Wuhan University of Technology, University of Louisville, University of Waterloo, and Argonne National Laboratory), the Materials Chemistry Professor claims to have found a cheap solution to expensive lithium-ion batteries.
“I wanted to invent something that was better, much better, than lithium-ion batteries for small-scale stationary storage, and ultimately for automotive [uses],” Sadoway admitted.
To find a suitable substitute for volatile lithium, Sadoway turned to the second-most commercially available and most Earth-abundant metal: aluminum. Next, the MIT professor pegged the cheapest non-metal available, sulfur, as the battery’s other electrode. To relay ions between the two points, Sadoway adopted a molten salt electrolyte. While the battery’s composition prioritizes cost-efficiency and easily-obtainable resources, Sadoway cites several additional advantages.
“The ingredients are cheap, and the thing is safe—it cannot burn,” proclaimed Sadoway.
The aluminum-sulfur battery still prizes heat, however. Studies showed that the unit actually charged 25 times faster at 110 degrees Celsius (230 degrees Fahrenheit) compared to 25 C (77 F). What’s more, the battery generates heat during both charging and discharging periods. This allows it to maintain an optimal operating temperature while keeping the salt solution from freezing.
The molten salt electrolyte also dissolves accumulative metal dendrites, which can span the two electrodes over time and cause shortages. This cheap and stable battery may not make its way into vehicles immediately, but Sadoway believes it can help speed charge times in the near future. Installed at charging stations, the battery system could store power before quickly releasing it to customers, minimizing wait times.
Sadoway already licensed the system’s patents to his newly co-founded company, Avanti.
“The first order of business for the company is to demonstrate that it works at scale,” Sadoway confessed.