Harvard scientists and engineers have demonstrated a new type of battery that could make power from renewable energy sources such as wind and solar far more economical and reliable. The battery technology was reported in a paper published in Nature.
Under the OPEN 2012 program, the Harvard team received funding from the U.S. Department of Energy’s Advanced Research Projects Agency—Energy (ARPA-E) to develop the innovative grid-scale battery.
The paper reports a metal-free flow battery that relies on the electrochemistry of naturally abundant, inexpensive, small organic (carbon-based) molecules called quinones, which are similar to molecules that store energy in plants and animals.
Intermittent wind or solar resources are inhibited by the lack of affordable storage technologies that can release power on demand. Flow batteries store energy in chemical fluids contained in external tanks instead of within the battery container itself. The electrochemical conversion hardware through which the fluids are stored and the chemical storage tanks may be independently sized. Thus the amount of energy that can be stored is limited only by the size of the tanks. The design permits larger amounts of energy to be stored at lower cost than with traditional batteries.
By contrast, in solid-electrode batteries, such as those commonly found in cars and mobile devices, the power conversion hardware and energy capacity are packaged together in one unit and cannot be decoupled. Consequently they can maintain peak discharge power for less than an hour before being drained, and are therefore ill suited to store intermittent renewables.