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On an arid mountain in Eureka County, Nev., a mining company believes it’s struck the 21st century equivalent of gold.

The precious commodity is vanadium, a metal that can be extracted from shale rock and used to make powerful, long-lasting batteries for cars, homes and utilities.

If Vancouver-based American Vanadium gets federal approval for its proposed Gibellini Hill Project — a 30-day public comment period ends May 29 — it will operate the only vanadium mine in the United States.

Eureka, indeed! The battle to build a better battery is intensifying as the United States and other countries, faced with growing global demand for electricity and a need to reduce the greenhouse gas emissions that worsen climate change, look to expand carbon-free renewable energy such as wind and solar.

MORE: USA TODAY energy news

Batteries are key. They can directly power electric cars and buses and, indirectly, homes and big buildings by storing solar and wind power for times when the sun doesn’t shine and the wind doesn’t blow. They balance out renewables that produce energy intermittently so consumers can power up laptops or run refrigerators 24/7.

The race is on. Universities, start-ups and major companies are working with new materials such as vanadium or tweaking the lithium-ion battery that Sony introduced more than 20 years ago for personal electronics. Some advances, like ones that Toyota and IBM are developing to power cars for 500-plus miles on a single charge, won’t make it to market for at least five years.

Others are making their debuts this year, including a battery by Ontario, Canada-based Electrovaya that enables homes with solar panels to go entirely off grid or one by General Electric that will be paired with a Texas wind farm to provide continuous power.

“It’s the dawn of the energy-storage age,” says Bill Radvak, president of American Vanadium, which is partnering with the German CellCube battery manufacturer Gildemeister. He says storage could be the “holy grail” for renewable energy. “There was no major battery market three years ago,” he says, adding that is changing quickly.

In February, California, which mandates that 33% of its electricity come from renewable sources by 2020, required a Los Angeles-area utility to ensure some capacity comes from energy storage. On May 1, Germany, which is shuttering its nuclear power plants as it boosts renewables, began subsidizing homeowners’ purchases of batteries to store power from solar panels. China’s five-year plan calls for 5% of all electricity to be stored by 2020. In the United States, about 2% of electric capacity is pumped hydro storage, the most common form of energy storage.

The global market for storing power from solar panels is forecast to explode, from less than $200 million in 2012 to $19 billion by 2017, according to a report this month by IMS Research.

One factor driving this growth is the plummeting price of renewables, especially solar panels that have fallen at least 60% since the beginning of 2011. As a result, industry groups report historic growth as U.S. electric capacity from solar panels jumped 76% and from wind turbines, 28%, last year alone.

OBSTACLES AHEAD

Still, batteries face obstacles, including cost and safety. Lithium-ion batteries aboard two Boeing 787s jets failed in January, causing a fire on one and smoke on the other. In March, batteries from the same manufacturer caused problems in two Mitsubishi vehicles: a hybrid Outlander car overheated and an all-electric i-MiEV caught fire during testing at an assembly plant.

While the EV industry says these incidents are the exception rather than the rule, money has also been a problem. In October, Massachusetts-based A123 ,a lithium-ion battery manufacturer that spent $132 million in federal stimulus funds, filed for bankruptcy. In December, Wanxiang American, the U.S. arm of a Chinese automotive parts giant, bought A123’s technology.

Toyota’s Jaycie Chitwood said lithium-ion batteries are just too expensive to make electric cars cost competitive without subsidies. Speaking at the Advanced Energy 2013 conference last month in New York City, she said Toyota is expanding its line of electric vehicles to meet the U.S. government’s fuel-efficiency targets — not because they’re profitable. She said it gives a $14,000 discount for each new electric RAV4.

Chitwood said a major battery advance is needed. Toyota is working on several alternatives, including cheaper, longer-range batteries that use magnesium instead of lithium. Commercialization, though, is years away.

“Batteries continue to be a challenge,” especially those for electric vehicles, Esther Takeuchi,chemistry professor at SUNY Stony Brook, said at the same conference. “Things aren’t where we’d want them to be, but they’re getting closer.”

Her university and others, some with federal funding, are looking not only at new chemical mixes but also at nano-sizing the chemical elements — or making them microscopically small — to make them more efficient. Takeuchi said successful batteries often have specific applications, such as lead-acid ones for auto ignition or lithium-iodine for pacemakers. She said lithium-ion has worked well in cellphones and laptops, their initial use.

Batteries will improve “but not at the pace that we’ve seen in recent years,” writes Richard Muller, a physics professor at the University of California-Berkeley, in his 2012 book, Energy for Future Presidents: The Science Behind the Headlines. He says the growing demand for portable electronics sped the development of already-known battery technologies. He says it will take awhile to commercialize new ones such as lithium-air.

Batteries are just one of many ways to store grid-scale energy. The most common is pumped hydroelectric, in which water is sent to a reservoir and released later to run generators.

“Storage is the glue that can hold the grid together,” said Matthew Maroon of GE Energy. GE, which opened a $100 million factory in Schenectady, N.Y., to build a sodium nickel chloride battery, announced earlier this month that Invenergy will install its Brilliant wind turbine with Durathon batteries at a Texas wind farm later this year.

The U.S. government is promoting energy storage. In November, the Department of Energy announced grants for 23 R&D projects and picked Argonne National Laboratory in Lemont, Ill., as the first national “innovation hub” for batteries and energy storage. Argonne will receive $120 million over five years for this work.

Batteries are getting particular attention, because they’re versatile. While pumped hydro facilities require lots of land and water and are meant for utility-scale projects, batteries can be used anywhere and are easily scalable so they can help power not only a car but a factory.

“Everyone’s finally realizing, ‘Hey, this works.’… It’s the key to the future,” says Brad Roberts of the Electricity Storage Association, an industry group. He says the industry’s hiccups are part of its growth and adds: “I don’t see any hesitation on the part of venture capitalists.”

ALTERNATIVES IN THE WORKS

IBM’s Allan Schurr is bullish on his company’s new lithium-air battery, which takes in oxygen from the air to form a chemical reaction that generates an electric charge. It’s lighter and denser than the lithium-ion ones in most of today’s electric vehicles, which use heavy metal oxides to drive the chemical reactions that produce power.

“The performance we’ve seen in tests so far is at or above our expectations,” he says. With 500 miles on a single charge, he says, “You’d take the ‘range anxiety’ out of the equation.” The current Nissan Leaf gets up to 75 miles on a single charge, and the Mitsubishi i-MiEV, 62 miles. Schurr expects a prototype to be developed next year, but its commercial availability will take at least five years.

Toshiba has developed a rechargeable lithium-ion battery, the SCiB, that has a new oxide-based material, lithium titanate, that allows quicker charging times. It’s used in the Honda Fit’s EV and Mitsubishi’s i-MiEV.

Huge lithium-ion batteries, filling 53-foot shipping containers, are being used for grid-scale projects. Since September 2011 on a ridge of Laurel Mountain in West Virginia, AES Storage has used them to store 64 megawatts of energy generated by windmills. That capacity, if it ran continuously, would be enough to power nearly 50,000 U.S. households for a year.

Batteries are also taking homes off the grid or providing back-up energy. SolarCity, a California-based solar installer, is piloting a back-up battery for some of its solar projects in California and may extend that option to other states this year. Minnesota-based Juhl Energy’s SolarBank system pairs solar panels with batteries. Detroit-based Nextek Power Systems offers a portable off-grid option that combines a solar panel with a battery.

Ontario-based Electrovaya plans to bring to the U.S. market this year a residential system, now being tested in Canada, that would install solar panels and a big-enough lithium-ion battery that homes could go completely off grid. Sankar Das Gupta, the company’s CEO, says it would cost less than $10,000 for an average-size home to add such a battery to a solar array.

“There’s no one battery technology that is one-size-fits-all,” says GE’s Maroon. He says each has its own advantages and disadvantages, adding: “The market is big enough for each technology to survive.”

American Vanadium says flow batteries that use vanadium last longer and are more powerful than lithium-ion ones, because they absorb and release huge amounts of energy quickly and can do so thousands of times. They can be used for grid-scale projects, and smaller lithium-vanadium batteries can power vehicles.

Radvak says if his project is approved, it could provide 5% of the world’s vanadium supply and help reduce battery costs. The Bureau of Land Management, which is examining the project and will hold a public meeting Tuesday in Eureka, says the mine could cause a loss of habitat for greater sage grouse and of acreage for livestock grazing.

“There is no mining operation that doesn’t have a consequence,” Radvak says. But he says the Eureka mine won’t involve moving lots of earth, because the vanadium is in surface deposits and can be simply leached with a sulfuric acid. “It’s a very low-risk project,” he says.

Radvak says while the U.S. has lagged behind other countries, notably Germany, on energy storage, he expects that in the long run, it will become the world’s leader.

GLOSSARY OF COMMON BATTERIES:

Batteries often work the same basic way even if they use different metals. They’re mini power plants that produce electricity by creating chemical reactions. As atoms move between two plates of different metals, via a chemical solution called an electrolyte, they produce voltage that is discharged through a metal wire on the other side.

• Lead-acid: (auto ignition). They have atoms pass from a plate of metallic lead through sulfuric acid to a plate of solid lead oxide.

• Lithium-ion (personal electronics, electric vehicles). They have carbon on one end and a metal oxide on the other, using lithium salt in an organic compound as the electrolyte in the middle.

• Lithium-air (still in development; possible uses include electric vehicles). They use lithium metal and oxygen as inputs at the two ends.

• Nickel-cadmium (portable electronics, electric vehicles). Their metal plates are nickel oxide hydroxide and cadmium.

• Sodium-sulfur (electric vehicles, grid-scale storage). A type of molten-salt battery, it’s made from liquid sodium and sulfur.

• Vanadium redox flow (grid-scale storage). They use vanadium, a metal named for Vanadis — the Scandinavian goddess of beauty and youth — in different oxidation states to store chemical energy for repeated use.