Science Daily looks closely at an affordable, efficient, non-toxic battery that runs your home smoothly from intermittent power sources:
The mismatch between the availability of intermittent wind or sunshine and the variability of demand is a great obstacle to getting a large fraction of our electricity from renewable sources. This problem could be solved by a cost-effective means of storing large amounts of electrical energy for delivery over the long periods when the wind isn’t blowing and the sun isn’t shining.
In the operation of the battery, electrons are picked up and released by compounds composed of inexpensive, earth-abundant elements (carbon, oxygen, nitrogen, hydrogen, iron and potassium) dissolved in water. The compounds are non-toxic, non-flammable, and widely available, making them safer and cheaper than other battery systems.
“This is chemistry I’d be happy to put in my basement,” says Michael J. Aziz, Gene and Tracy Sykes Professor of Materials and Energy Technologies at Harvard Paulson School of Engineering and Applied Sciences (SEAS), and project Principal Investigator. “The non-toxicity and cheap, abundant materials placed in water solution mean that it’s safe — it can’t catch on fire — and that’s huge when you’re storing large amounts of electrical energy anywhere near people.”
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“We combined a common organic dye with an inexpensive food additive to increase our battery voltage by about 50 percent over our previous materials,” says [study co-leader Roy] Gordon[, Thomas Dudley Cabot Professor of Chemistry and Professor of Materials Science at Harvard]. The findings “deliver the first high-performance, non-flammable, non-toxic, non-corrosive, and low-cost chemicals for flow batteries.”
Unlike solid-electrode batteries, flow batteries store energy in liquids contained in external tanks, similar to fuel cells.