MIT has designed an ultra-low cost "flow" battery that it claims will store 10-times as much energy as lithium-ion while consuming 10,000 times less power, making it a candidate to meet the Department of Energy's target of less than $100 per kilowatt-hour for grid-scale deployment: R. Colin Johnson @NextGenLog
MIT's flow battery simplifies rechargeable technology by eliminating the ion-exchange membranes. The lower solid graphite electrode reduces liquid bromine to hydrobromic acid, while hydrogen is oxidized at the upper porous electrode. Further Reading