Long-lasting flow battery could run for more than a decade with minimum upkeep
February 13, 2017
Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed a new flow battery that stores energy in organic molecules dissolved in neutral pH water. This new chemistry allows for a non-toxic, non-corrosive battery with an exceptionally long lifetime and offers the potential to significantly decrease the costs of production.
The research, published in ACS Energy Letters, was led by Michael Aziz, the Gene and Tracy Sykes Professor of Materials and Energy Technologies and Roy Gordon, the Thomas Dudley Cabot Professor of Chemistry and Professor of Materials Science.
Flow batteries store energy in liquid solutions in external tanks — the bigger the tanks, the more energy they store. Flow batteries are a promising storage solution for renewable, intermittent energy like wind and solar but today’s flow batteries often suffer degraded energy storage capacity after many charge-discharge cycles, requiring periodic maintenance of the electrolyte to restore the capacity.
By modifying the structures of molecules used in the positive and negative electrolyte solutions, and making them water soluble, the Harvard team was able to engineer a battery that loses only one percent of its capacity per 1000 cycles.
“Lithium ion batteries don’t even survive 1000 complete charge/discharge cycles,” said Aziz.
“Because we were able to dissolve the electrolytes in neutral water, this is a long-lasting battery that you could put in your basement,” said Gordon. “If it spilled on the floor, it wouldn’t eat the concrete and since the medium is noncorrosive, you can use cheaper materials to build the components of the batteries, like the tanks and pumps.”