Aug 182013
 

20130815162848-0

Design may support widespread use of solar and wind energy.

MIT researchers have engineered a new rechargeable flow battery that doesn’t rely on expensive membranes to generate and store electricity. The device, they say, may one day enable cheaper, large-scale energy storage.

The palm-sized prototype generates three times as much power per square centimeter as other membraneless systems — a power density that is an order of magnitude higher than that of many lithium-ion batteries and other commercial and experimental energy-storage systems.

The device stores and releases energy in a device that relies on a phenomenon called laminar flow: Two liquids are pumped through a channel, undergoing electrochemical reactions between two electrodes to store or release energy. Under the right conditions, the solutions stream through in parallel, with very little mixing. The flow naturally separates the liquids, without requiring a costly membrane.

The reactants in the battery consist of a liquid bromine solution and hydrogen fuel. The group chose to work with bromine because the chemical is relatively inexpensive and available in large quantities, with more than 243,000 tons produced each year in the United States.

In addition to bromine’s low cost and abundance, the chemical reaction between hydrogen and bromine holds great potential for energy storage. But fuel-cell designs based on hydrogen and bromine have largely had mixed results: Hydrobromic acid tends to eat away at a battery’s membrane, effectively slowing the energy-storing reaction and reducing the battery’s lifetime.

To circumvent these issues, the team landed on a simple solution: Take out the membrane.

“This technology has as much promise as anything else being explored for storage, if not more,” says Cullen Buie, an assistant professor of mechanical engineering at MIT. “Contrary to previous opinions that membraneless systems are purely academic, this system could potentially have a large practical impact.”

Buie, along with Martin Bazant, a professor of chemical engineering, and William Braff, a graduate student in mechanical engineering, have published their results this week inNature Communications.

“Here, we have a system where performance is just as good as previous systems, and now we don’t have to worry about issues of the membrane,” Bazant says. “This is something that can be a quantum leap in energy-storage technology.”

Possible boost for solar and wind energy 

Low-cost energy storage has the potential to foster widespread use of renewable energy, such as solar and wind power. To date, such energy sources have been unreliable: Winds can be capricious, and cloudless days are never guaranteed. With cheap energy-storage technologies, renewable energy might be stored and then distributed via the electric grid at times of peak power demand.

“Energy storage is the key enabling technology for renewables,” Buie says. “Until you can make [energy storage] reliable and affordable, it doesn’t matter how cheap and efficient you can make wind and solar, because our grid can’t handle the intermittency of those renewable technologies.”

By designing a flow battery without a membrane, Buie says the group was able to remove two large barriers to energy storage: cost and performance. Membranes are often the most costly component of a battery, and the most unreliable, as they can corrode with repeated exposure to certain reactants.

Braff built a prototype of a flow battery with a small channel between two electrodes. Through the channel, the group pumped liquid bromine over a graphite cathode and hydrobromic acid under a porous anode. At the same time, the researchers flowed hydrogen gas across the anode. The resulting reactions between hydrogen and bromine produced energy in the form of free electrons that can be discharged or released.

The researchers were also able to reverse the chemical reaction within the channel to capture electrons and store energy — a first for any membraneless design.

In experiments, Braff and his colleagues operated the flow battery at room temperature over a range of flow rates and reactant concentrations. They found that the battery produced a maximum power density of 0.795 watts of stored energy per square centimeter.

Read more . . .

 

The Latest on: Flow battery
  • Using Crumpled Graphene Balls to Make Better Batteries
    on January 18, 2018 at 7:22 am

    “In current batteries, lithium is usually atomically distributed in ... Because miniature paper balls are conductive and allow lithium ions to flow rapidly along their surface, the scaffold creates a continuously conductive, dynamic, porous network ... […]

  • Sparton Resources Inc.: Drill Program to Begin on Quebec Gold Property Vanadium Developments and Flow Battery Marketing Initiatives Continue
    on January 18, 2018 at 6:04 am

    TORONTO, ONTARIO--(Marketwired - Jan 18, 2018) - Sparton Resources Inc. (TSX VENTURE:SRI) ("Sparton" or the "Company") announced today that it has signed a drill contract with Edcor Drilling Services for a minimum of 1,000 metres of core drilling on the ... […]

  • Unexpected phenomenon observed in Lithium-Ion batteries
    on January 18, 2018 at 1:52 am

    When a lithium-ion battery supplies electricity, lithium ions flow into empty sites in the atomic lattice. This diagram shows the spread of positively charged lithium ions across the custom-built FeF2 nanoparticle. The conversion reaction sweeps rapidly ... […]

  • Lockheed Martin eyes partners for flow battery development
    on January 17, 2018 at 2:32 am

    Lockheed Martin Energy is seeking development and manufacturing partners in the solar energy industry in advance of its plans to roll out its long-duration flow battery at the end of 2018. The company is already well established in development of lithium ... […]

  • Low-cost, battery-powered rate and total flow indicator
    on January 16, 2018 at 8:32 am

    The Pulsite Solo from Titan Enterprises is a low-cost, battery-powered rate and total flow indicator. These panel or surface mounting digital instruments, that require no external power when used with magnetic sensors or contact closures, are designed to ... […]

  • Lockheed Martin eyes solar partners for new flow battery
    on January 16, 2018 at 5:42 am

    Lockheed Martin Energy is looking for development and manufacturing partners in the solar industry as it readies its long-duration flow battery at the end of the year. The company has an established lithium-ion business but will add a flow battery to its ... […]

  • Get Ready For The Battery Revolution
    on January 13, 2018 at 4:52 pm

    Large batteries could help even out that energy flow and give people the ability to become energy self-sufficient by combining batteries with home solar panels. Elon Musk’s battery wall already offers that ability, but Toney believes we’ll see the ... […]

  • A big battery may work better than a power plant
    on January 10, 2018 at 9:15 am

    The other potentially exciting development in bulk grid energy storage is the Vanadium Redox Flow batteries (VRFB), capable of significant capacity storage, long-term use, rapid discharge and full use (lithium-ion batteries typically only use 80% of their ... […]

  • HCP Installing Primus Power Energy Storage Systems at Life Science BuildingsFlow battery system manages electrical loads to generate savings
    on January 8, 2018 at 4:00 am

    HAYWARD, Calif., Jan. 08, 2018 (GLOBE NEWSWIRE) -- Primus Power (“Primus”), a leader in stationary energy storage systems, announced today that it has received orders to install flow battery systems at multiple life science buildings owned by HCP, ... […]

via Google News and Bing News

Other Interesting Posts

Leave a Reply

%d bloggers like this: