Researchers at MIT have created a new rechargeable flow-battery that they think may enable cheaper energy storage in the future on a large scale. Their prototype, which is about the size of a palm right now, doesn’t rely on membranes in order to generate and store electricity, and yet is able to generate three time as much power per square centimeter as other batteries without membranes. This power density is an order of magnitude higher than many of the lithium-ion batteries currently in use, as well as other experimental energy storage systems.
The battery utilizes a phenomenon called laminar flow, in which two liquids are pumped through a channel and undergo electrochemical reactions, ideally in parallel streams with mixing prevented by the flow itself. The prototype uses a liquid bromine solution and hydrogen fuel, chosen because bromine is abundant and relatively cheap while also reacting well with hydrogen. This combination has been attempted before with mixed results due to the tendency of hydrobromic acid to eat at the battery membrane, effectively reducing the life of the battery as well as slowing the energy-storing reaction. The solution for this prototype was to remove the membrane entirely.
Cullen Buie, an assistant professor of mechanical engineering at MIT, claims that the prototype is as promising for the future of energy storage as anything else being currently attempted, as well as provides practical real world use for a concept, membraneless system, previously thought to be purely academic. Buie recently co-published the results of the prototype in Nature Communications alongside Martin Bazant, a professor of chemical engineering, and William Braff, a mechanical engineering graduate student. Buie continued, stressing the importance of energy storage, commenting that technologies such as solar and wind energy generation have a lessened impact without a storage capability to make up for their intermittency.
Read the full article here: New Flow Battery Could Enable Cheaper, More Efficient Energy Storage