MIT Researchers Unveil Innovative Battery Prototype

MIT researchers have devised a membrane-free rechargeable battery prototype that could facilitate cheaper, large-scale energy storage and support widespread renewable energy use.

On August 16, 2013, researchers at the Massachusetts Institute of Technology (MIT) unveiled a membrane-free rechargeable flow battery prototype capable of overcoming the major barriers of energy storage – cost and performance – by eliminating the need for expensive membranes and delivering a power density an order of magnitude exceeding lithium-ion batteries and up to three times greater than other membrane-free systems.  According to the researchers, the palm-sized prototype can be scaled up to facilitate cheaper, utility-scale energy storage and support widespread use of intermittent renewable energy sources.

Flow Battery Process (deeyaenergy)

The device utilizes a process called laminar flow, whereby two liquids are pumped through a channel to undergo electrochemical reactions between two electrodes.  Under the right conditions, the liquids retain respective parallel courses with minimal mixing despite the absence of a separating membrane.  The battery reactants consist of hydrogen fuel and bromine, a chemical that is relatively cheap and abundant in the U.S.  Though hydrogen-bromine fuel cells have substantial potential for energy storage, the corrosive property of hydrobromic acid significantly reduces the lifespan of conventional membrane-based flow batteries, a disadvantage that the new membrane-free battery overcomes.

The researchers reported a maximum power density of 0.795 Watts of stored energy per square centimeter at room temperature.  Additionally, their predictions from a mathematical model of the system agreed with experimental results, providing positive implications for future iterations and scalability.  The performance level could put the prototype on track to produce energy at $100 per Kilowatt-Hour, the goal set by the Department of Energy for economical utility-scale energy storage.  Flow batteries are crucial to address the intermittency of renewable energy sources, such as wind and solar by facilitating their storage and distribution via the electric grid during peak load times.

August 19, 2013 via Energy Solutions Forum