Cheap flow batteries could pave the way for more renewables

9 January 2014 — A cost-effective method of storing energy from intermittent renewables like wind power and solar PV has been devel0ped, according to the  journal Nature.

A flow battery made from inexpensive materials has been described by Harvard researchers in A metal-free organic–inorganic aqueous flow battery, opening the possibility of cheap, large-scale energy storage.

Unlike conventional batteries, the electro-active components of flow batteries are held in fluid form external to the battery itself, enabling the systems to store large amounts of energy. Flow batteries are therefore attractive as a potential means for regulating the output of intermittent energy sources, like wind and solar.

Previously, such systems have been limited by the availability and cost of suitable materials, though study authors Michael Aziz and colleagues have developed a metal-free aqueous flow battery based on low-cost chemicals called quinones, which they said can be synthesised from inexpensive chemicals.

“The whole world of electricity storage has been using metal ions in various charge states but there is a limited number that you can put into solution and use to store energy, and none of them can economically store massive amounts of renewable energy,” researcher Roy Gordon said. “With organic molecules, we introduce a vast new set of possibilities.”

The authors said the novel battery design represented a promising direction for realising massive electrical energy storage at a greatly reduced cost.

Read more at Nature.