It only takes a few exploding phones to realize that we live in a compromise - lithium-ion batteries, the most used kind of battery today, are both potentially risky and not almost long-lasting enough.
The fact that the amount of energy a flow battery is able to store is limited only by the size of the tank makes it "a promising storage solution for renewable, intermittent energy like wind and solar".
However, by modifying the solution, the Harvard researchers could make a battery that only lost one per cent of its capacity for every 1,000 cycles. Current batteries typically last fewer than 1,000 full charge-discharge cycles or going from completely flat to fully charged.
"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 lead author Roy Gordon, the Thomas Dudley Cabot Professor of Chemistry and Professor of Materials Science.
"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". As it's not corrosive or toxic, you don't have to worry about wrecking your home if the battery leaks - you might just need a mop.
Regarding cost, the Department of Energy (DOE) in the United States has set a goal of building a battery that can store energy for less than $100 per kilowatt-hour, which would make stored wind and solar energy competitive to energy produced from traditional power plants.
The newly developed power technology is used in what is called a "flow battery". The battery also needs less maintenance than the traditional.
The key to the technology is to use ferrocene, a molecule well known for its electrochemical properties, for the positive electrolyte.
By functionalizing the molecules, the researchers succeeded in making viologen more resilient and ferrocene water-soluble.
"It becomes cost effective to put batteries in so many places. This research puts us one step closer to reaching that target". Well, flow batteries aren't particularly well catered to mobile applications, but Harvard's work could apply to large energy storage efforts like those from solar and wind power, cheapening the infrastructure needed to reduce fossil fuel consumption.