Story URL: http://news.medill.northwestern.edu/chicago/news.aspx?id=155462
Story Retrieval Date: 7/31/2014 10:32:04 AM CST
Scientists hope funding to develop an electric car battery that breathes air and could eliminate gasoline in the process will come with the $532 million allocated for Argonne National Laboratory in the proposed federal budget.
A single car can emit tons of greenhouse gases into the atmosphere each year. To curb the threat of these emissions, President Obama submitted a $28.4 billion fiscal year 2011 budget request for the Department of Energy to focus on research and development of clean and efficient energy.
Researchers in the Advanced Lithium Battery program at Argonne, operated by the DOE, are creating a pioneering lithium-air battery for electric cars. It promises to deliver at least five time more energy than lithium-ion batteries now used in hybrid cars.
“The first generation of completely electric vehicles will use lithium-air batteries,” said Jeffrey Chamberlain, of the Office of Technology Transfer at Argonne.
Known as Li-air for short, the batteries mean more mileage per charge.
“The Li-ion battery can provide a 100 mile range in electric cars now,” said Khalil Amine, a material scientist and manager of the Advanced Battery Technology Group at Argonne. “The Li-air will enable at least 400 to 500 miles.”
The Li-air initiative is part of an Argonne Laboratory-Directed Research and Development grand challenge program and will pave the way for a new generation of advanced high-energy battery technology.
And although Li-air batteries have already been around for more than 20 years as primary-use, or one-time use, batteries, Amine said the Argonne team is working to improve the model by making it rechargeable through home outlets.
Li-air batteries combine lithium ions and oxygen to create a lithium oxide, or peroxide, which produces energy through electron transfer. And while Li-ion batteries can deliver about 180 watt-hours of electricity per kilogram weight of the battery, Li-air batteries could be able to reach 11,000 watt-hours per kilogram.
“Lithium-air has approximately the same energy of a [typical car] engine,” Amine said.
Even better, the Li-air battery uses air or pure oxygen to stimulate energy production.
As Chamberlain explained it, the battery literally breathes.
Oxygen enters the battery through the porous cathode and reacts with the lithium ions released from the anode. This reaction causes electrons to break free from the lithium ions and creates energy flow.
But despite many advances in research, Amine said breakthroughs are still needed to solve some lingering problems.
“The catalyst being used right now is not stable,” he said. “Stability is important because the catalyst needs to remain highly active in order to have the chemical reaction take place reversibly.”
The metal used as the catalyst, manganese oxide, starts to change after numerous chemical reactions between oxygen and lithium ions take place. This makes the lifespan of the battery unreasonably short.
“It’s like pancakes on a frying pan,” Chamberlain said. “The frying pan’s surface changes after cooking the first pancake and the second pancake won’t be cooked the same way as the first.”
But Amine said he is confident the problems with Li-air will be solved in the future.
“Lithium-ion had a lot of problems 15 years ago,” he said. “But now there are a lot of people who have worked on it and developed it. Li-air will follow the same path.”
And in order to expedite the solution process, Amine said more teams are needed to improve Li-air research.
“We have initiated a good program and team at Argonne,” he said. “But we want to keep collaborating and eventually bring in more outside expertise to join our team at Argonne. It can be a global effort and we will lead it.”
And when can consumers expect to see the battery in cars and on store shelves?
Chamberlain said, although commercial release of Li-air is not expected in the near term, Obama’s requested budget for 2011 will hopefully speed up the process.
“In the big scheme of things, the budget really is taking seriously the funding for science and technology and what it can do for national defense and the economy,” he said.
“If the Li-air and Li-ion are the same size and the same price, you are essentially getting more for your money if you buy the Li-air.”