Lithium cells the size of rice

A video on Treehugger shows how scientists have produced lithium-ion batteries from a nozzle the width of a human hair. Although only ever likely to be used for small, low power gadgets, these minute batteries actually deliver enough current to be of real use, unlike previous attempts using thin-film printing.

The team that produced this marvel of miniaturisation works at the Wyss Institute for Biologically Inspired Engineering at Harvard University.

Battery key to solar-powered plane

Across America – Golden Gate Flight © Solar Impulse / J. Revillard

Photo: Across America – Golden Gate Flight, © Solar Impulse / J. Revillard

Press reports of the Solar Impulse sun-powered aircraft’s nighttime touchdown at Washington DC underscored the key role batteries play in putting solar power to work. According to the Solar Impulse web site, though, the plane, which is currently crossing America, does not rely on bog-standard battery technology. Instead, Korean manufacturer Kokam is said to have cooked up a lithium polymer battery pack which is “two years ahead of the industry.”

While the project team may be understandably reluctant to reveal details of the technology, it is good at least to see this example of energy storage innovation flying high.

Lithium-sulphur makes a splash

Oak Ridge National Laboratory develop lithium-sulphur battery

New lithium-sulphur battery. Photo courtesy of Oak Ridge National Laboratory.

Lithium-sulphur technology batteries made headlines this week with the announcement that a consortium of leading energy companies is planning to develop what it describes as “safe, lightweight and robust solar energy storage systems for the military around the world.”

The group consists of battery developer OXIS; battery, charger and power management company Lincad; PureWafer, from the photovoltaic sector; and inverter manufacturer Solutronic. The consortium cites lithium-sulphur cell technology as being extremely lightweight and able to withstand extreme abuse, making it ideal for military applications.

Another factor in lithium-sulphur’s favour is its potential to outclass traditional lithium-ion in the capacity stakes. According to Megan Treacy, reporting for Tree Hugger, researchers at Oak Ridge National Laboratory in Tennessee, USA, have developed units that store four times as much energy as a lithium-ion battery. It is claimed to be cheaper to make and safer, too.

A previous hitch with the technology was overcome by switching to a solid electrolyte, says the research team.

Long-life lithium still going strong

One of the many controversies surrounding electric vehicles is the longevity, as well as the cost, of the lithium-ion batteries used to power them. Various schemes have been suggested and implemented to replace power units which regularly lose a crucial percentage of their charge capacity long before the owner is considering buying a new vehicle.

Now comes news that battery exchanges, redeployment to the grid, recycling and all the rest of it may be a thing of the past due to a battery developed by the Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg (Baden-Württemberg Centre for Solar Energy and Hydrogen Research, aka ZSW) in Germany. Its 18650-format lithium-ion battery still retains 85% of its charge after 10,000 cycles.

That works out at more than 27 years of completely charging and recharging the unit once a day, every day. The battery’s power density is 1,100W per kg and ZSW researchers believe they would also have applications in grid-scale storage.

A catalyst for lithium-air batteries?

Lithium-air cells have massive potential, say scientists. With 10 times the energy storage potential of the batteries currently in widespread use, they represent one of the Holy Grails of energy storage for electric vehicles, and much more besides. The one major drawback in their development has been the catalyst. Until now, manufacture has been slow, complex and used very expensive metals, such as platinum.

Researchers at Los Alamos National Laboratory say they’ve potentially changed all that, reports Science Daily, with a new catalyst based on nitrogen-containing carbon nanotubes. What’s more, the lab has developed an ingenious method for synthesising the new catalyst, using readily available chemicals that allow preparation of the material in a single step.

Three ways to increase adoption

1Energy Systems

Pic courtesy of 1Energy Systems

Positive indicators for the forward march of energy storage continue to abound, such as the inclusion of the sector in McKinsey Global Institute’s list of 12 Disruptive Technologies That Are Changing The World. Meanwhile, ASD Reports forecasts the grid-scale battery market will top USD$1 billion for the first time by the end of the year and Lux Research projects more than 10 times that figure in 2017.

But as we’re always asking at Energy Storage Report, where is all this lovely money going to come from? The first answer is software. 1Energy, a startup from Seattle, USA, is looking for a way to improve the interoperability of large-scale batteries and thus allow the seamless use of different battery types in one energy storage project.

“We envision a future when there are various storage sockets, if you will… and battery manufacturers can sell energy storage in the same way a transformer manufacturer would sell catalogue products to the utility today,” David Kaplan, the company’s chief executive, told the Electricity Storage Association annual conference this month.

By overcoming the lack of scalability and modularity through software, Kaplan thinks utilities will be far happier to commit to battery energy storage as they would not be tied to one supplier. Another option for adoption, and probably the most newsworthy, is the possibility of tax credits for energy storage in the US.

The Storage Technology for Renewable and Green Energy Act was introduced in the 112th Congress with bipartisan support and now has been re-introduced. If passed, it would allow credits for almost all types of energy storage.

And a third adoption driver could be from improving relations between technology suppliers and large corporations, financiers, government, educational and other bodies to form what Lux Research describes as “megaclusters”, with complex, interlocking relationships (as reported in Renewable Energy World). If you aware of any other initiatives, tell us.

Eos Energy Storage raises $15 million

Eos Energy Storage grid-scale energy storage

Pic courtesy of Eos Energy Storage

Eos Energy Storage has announced the completion of its USD$15 million Series B financing round with participation from a syndicate of 21 strategic and financial investors. The round supports Eos’s commercialisation of its safe, low-cost and long-lasting grid-scale battery technology.

Eos’s Aurora grid-scale energy storage product has been specifically engineered to help utilities operate more efficiently and create savings for consumers by time-shifting peak energy demand while providing greater resilience to the electricity grid. Eos will begin deploying the Aurora in 2014. The company is in advanced discussions with several US states regarding the location of its pilot manufacturing facilities.

Two high-profile investors in this round are Princeton, New Jersey-based NRG Energy and Fisher Brothers. Eos is NRG’s first investment in the energy storage industry. Fisher Brothers is a privately owned New York City-based real estate firm which owns Plaza Construction, a contractor with experience building urban power plants and renewable energy projects.

Fisher Brothers is also a co-sponsor, with Morgan Stanley, of the City Investment Fund, a founding member of Perella Weinberg Partners and a founding partner of Convergent Energy + Power, an energy storage asset development company.

New routes to compressed air storage

Enough Northwest US wind energy to power about 85,000 homes each month could be stored in porous rocks deep underground for later use, according to a new study. Researchers at the Department of Energy’s Pacific Northwest National Laboratory and Bonneville Power Administration have identified two unique methods for this energy storage approach, and two eastern Washington locations to put them into practice.

The world’s two existing compressed air energy storage plants (one in Alabama, the other in Germany) use man-made salt caverns to store excess electricity. The study examined a different approach: using natural, porous rock reservoirs that are deep underground to store renewable energy. Analysis identified two particularly promising locations in eastern Washington.

One could access a nearby natural gas pipeline, making it a good fit for a conventional compressed air energy facility. The other, however, doesn’t have easy access to natural gas. So the research team devised a hybrid facility would extract geothermal heat from deep underground to power a chiller that would cool the facility’s air compressors, making them more efficient. Geothermal energy would re-heat the air as it returns to the surface.