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Inventing Batteries from Air

ARPA-e and others aim to fund development of a battery that relies on lithium and air
Lithium Ion Battery



Claus Ableiter via WikiMedia Commons

The last of a four part series. Click here for part one, here for part two and here for part three.

In his State of the Union address, President Obama painted a vision of the jobs of tomorrow -- then pointed to the scientists of today.

"None of us can predict with certainty what the next big industry will be, or where the new jobs will come from," Obama admitted. But historically, he said, the government has funded basic research that the private sector hesitated to fund itself. Decades later, some of these early forays in laboratories gave birth to entire industries, such as those built around the Internet and the Global Positioning System.

"Just think of all the good jobs -- from manufacturing to retail -- that have come from those breakthroughs," he said.

A new DOE agency, the Advanced Research Projects Agency-Energy, is key to the president's vision of scientific "breakthroughs" that can reshape energy, generate jobs and sharpen the United States' competitive edge.

Obama gave ARPA-E, as it's known, its first endowment in the American Recovery and Reinvestment Act. Over the past year and a half, the agency sought out "game-changing" technologies now in their infancy at research labs, startup companies and some adventurous larger firms. It tried to assess the best projects, granted them between $1 million and $5 million, and issued this challenge: over three years, to advance their technology to a point where the private sector will snap it up.

Sixteen of these projects, totaling about $62 million, are applicable to electric cars. ARPA-E's director, Arun Majumdar, said there's a range of technologies and approaches. Each has a unique mountain to climb, whether it's reliability, cost, efficiency or a combination of these. "And I don't know which one is going to succeed," he said. "But if one of them does, I think it will be game-changing."

A vision of the ultimate battery
One of the most exciting prospects is lithium-air technology, a decade-old idea that many think could be the ultimate battery. Today's electric cars max out at 100 miles on a single charge, but lithium-air could theoretically make distances of 400 and 500 miles possible. Its cells pulse with so much energy, in fact, that it rivals gasoline.

A 2011 Honda Civic, driven to its last drop, travels about 350 miles. Lithium-air is one of the only batteries that can get in that ballpark without taking up much more space than an average lead-acid auto battery. If Americans see that equation and buy the cars en masse, transportation emissions will decline, because even with a power grid that's half coal-fired, charging an electric car still causes less emissions than an all-gasoline car.

The White House argues that if lithium-air achieves a breakthrough, or any of the other battery technologies do, the payoff will be huge. Money normally spent on foreign oil could stay in the U.S. economy. One-hundred-thirty-million cars in the United States, gradually turning electric, would revitalize the auto industry as well as its suppliers in the Midwest. More manufacturing jobs would sprout up to supply the tons of minerals and materials that go into the batteries. Used-up batteries could find a second life on the grid.

There is one big drawback: Today, no one knows how to make lithium-air batteries at the cost and quality necessary for an electric car. Indeed, the scientific barriers are deemed so high that the batteries are considered to be a possibility only 10 to 20 years from now.

ARPA-E is counting on researchers like Yangchuan Xing to wrest that future closer. Xing, an associate professor of chemical and biological engineering at Missouri University of Science and Technology, received one of two ARPA-E awards for lithium-air batteries.

Xing estimates that if lithium-air progresses like lithium-ion, the battery used in electric cars today, it will take 15 to 20 years to go commercial. But high-risk research like his -- which may catapult the technology ahead or slam into a dead end -- could change that calendar. "Obviously, if a breakthrough technology is successful, that's going to shorten the time a lot," he said.

Xing isn't the mad inventor working on rocket packs, mechanized human wings or time machines in his garage. To most, he probably comes off like most engineering professors: bookish, private, inclined to discuss factual matters rather than tarry on questions of meaning.

Yet in this anonymity, Xing has advanced science that could turn the dawn of the electric car into an era. It's sprung from careful, plodding chemistry, at the intersection of fuel cells and batteries, that he and a half-dozen graduate students have worked on for six years.

Finding its way to the ultimate risk-taker
A couple years ago, he realized this work could apply to lithium-air, already known as the holy grail of the field. Yet when he floated the idea to a few business contacts, they hedged. There was no guarantee the research would succeed, they pointed out, and the professor had no prototype to prove he could turn math into machines. Xing's idea was stranded.

Then ARPA-E was born, and he sensed a rare opportunity. So he called up some of his contacts from over the years -- a government lab, a small battery company, a nanotechnology research firm -- and decided to try his chances.

Xing's group was up against 220 other battery proposals, including plans from Stanford University, the Massachusetts Institute of Technology and companies with deep roots in government labs. Yet his idea made the final cut of 10 projects.

Now he has a $1.2 million grant to use over three years. After he hires some more researchers, the entire team will have about a dozen people.

So how exactly does one search for a breakthrough? Xing is cagey. Asked to expand on the specific work he's doing, he said he can't discuss the technical details of his research. He only said he's developing a new electrode and a new catalyst for lithium-air.

This is about as specific as a jet designer saying he's working on a new type of engine. But Xing isn't the only one treating his ARPA-E project sensitively. The other lithium-air awardee, PolyPlus Battery Company Inc., a spinoff from Lawrence Berkeley National Laboratory considered a world leader in the technology, didn't return ClimateWire's messages. Two other ARPA-E awardees, each working on other types of cutting-edge batteries, declined to talk to ClimateWire.

What is known about Xing's work is that it focuses on the major scientific challenges that keep lithium-air from practicality.

Most batteries are self-contained units. They hold materials whose chemical relationship essentially kicks electrically charged particles called ions from one side of the battery to the other. When ions get punted one way, the battery generates electricity; when they go the other direction, the battery stores energy.

Lithium-air batteries work similarly, but they aren't self-contained units. One of the "kickers" is actually a doorway to the outside world. It's a porous sheet whose only job is to let oxygen in, because that drives the chemical reactions that keep the kicking game going. This sheet takes up a lot less space than the solid material needed in other batteries, like iron, cobalt or manganese. Voilà: The battery holds just as much energy, but would take up a fifth of the space of lithium-ion batteries used in today's electric vehicles.

That sounds basic, but no one has found the right recipe yet. Indeed, scientists are still working out the basics.

What a 'breakthrough' has to be
Xing and his team are working on two aspects. The first is using nanotechnology to make a porous sheet that "breathes" oxygen more efficiently. The other challenge is finding a material that binds oxygen just as easily as it lets oxygen go; otherwise, the battery's not rechargeable, and it's useless for electric cars.

All of this work -- Xing's and the other ARPA-E projects -- occurs in the context that an interesting battery isn't always a useful one. For electric cars to succeed, ARPA-E reckoned, they need batteries that can be mass-produced. Moreover, they have to drive like gasoline cars without costing more.

So when ARPA-E offered funding, it set a few conditions. "Breakthrough" batteries should cost about a quarter of what car batteries cost today, while more than doubling the energy they can hold in the same area. This disqualified batteries with pricey ingredients like gold or platinum, for example, and other batteries that are cheap but pack no punch.

ARPA-E would give special consideration to batteries made differently than Asian competitors do and to batteries that show potential for mass-manufacturing on U.S. soil. "At the end of the day, we want the scaling in the United States of these successful technologies," said Majumdar, the ARPA-E chief.

By some indications, this is actually an area where the United States is several steps ahead of other countries. Japanese, Korean and Chinese companies are more focused on today's technology, fine-tuning the manufacturing to cement their lead in lithium-ion batteries, according to venture investor Dhiraj Malkani, a principal with RockPort Capital Partners. "There's not much disruptive innovation going on, on the technology side," he said.

That plays to a U.S. strength: the ability to discover cutting-edge ideas in universities and research labs. It also highlights a U.S. weakness: the tendency to find these ideas, then lose them to overseas developers. The missing link is often the lack of patient, private investors.

Majumdar and others say cutting-edge energy technologies are so risky and unmarketable that companies and investors won't play. So this is where ARPA-E comes in, Majumdar says. After three years of funding, an awardee should have enough science for a venture capitalist to say "yea" or "nay." The riskiness of the prospect becomes far less daunting.

Malkani, the venture investor from RockPort, agreed that many of the ARPA-E awardees, especially the ones coming from universities and labs, are too immature for him to take on right now.

"We just haven't found the right pick for us, from the standpoint of a technology that's really disruptive," he says. "We are tracking a couple things that fit that bill and look very promising."

Lithium-air fits the term "disruptive," but there's a reason he doesn't mention it. It has to do with the term "exit."

The role of the venture capitalist
Venture capitalists think of their investments as short-term relationships. When someone like Malkani sees a disruptive technology, he checks if the inventor has resolved the basic science questions and can actually do, in the lab where he controls all the conditions, what he says he can do.

If it checks out, he funds the inventor's startup company. Then he becomes one of its executives. Venture capitalists often join a company's board of directors; that lets them gauge, and guide, the company's progress. The goal is to turn an inventor's prototype into a product.

If that works, Malkani would help the company issue stock to raise more money -- "going public" -- and head on to his next project. Or he'd hand it to a larger company that thinks it has promise. This is normally where the venture capitalists "exit."

Venture capitalists generally want the process to take five years, but Malkani says seven to 10 years is typical. Lithium-air isn't near these timelines.

For the moment, venture investors are focused on lithium-ion, the lightest, most cost-effective battery for electric cars today. Matt Nordan, a vice president at Venrock, says that worldwide, companies and governments have plunged $4 billion into new lithium-ion factories in the last five years. "They're not going to abandon those facilities in short order and jump to a different kind of technology," he said.

Once these lithium-ion factories have run their course -- Nordan expects a changing of the guard as the decade closes -- technologies like lithium-air will come into view. "Electric vehicles will have gone through their stumbling in the early generations, just like the [Toyota] Prius did," and companies will build new battery plants, he said.

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500

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