Lithium-air batteries

[Serge]

Having had time to read the linked article (as opposed to relying on the quotes above) I've seen there is some 'cheating' going on with the numbers. The energy density they are quoting is for the cathode only.

A novice eye, like mine, can easily miss the crucial details. I derived the numbers from the following paragraph.

The newly developed lithium-air cell with alkaline aqueous electrolyte gel has a discharging capacity of approximately 9000 mAh/g when it is discharged in the air at a discharge rate of 0.1 A/g. The charging capacity is about 9600 mAh/g. These values are considerably larger than the reported values of conventional lithium-air batteries (700 - 3000 mAh/g). Furthermore, by using an alkaline aqueous solution in place of an alkaline water-soluble gel, continuous discharging up to 20 days at the discharge rate of 0.1 A/g in the air has been realized. The discharge capacity of the cell was approximately 50,000 mAh/g (shown in Fig. 3).

What's missing from this statement is cathode-only qualifier for the latter energy density figure (50 Ah/g) as you noted. What do you make of 9 Ah/g figure stated earlier? Is this the "true" overall cell energy density? In a sense, the 50 Ah/g figure is just "eye-candy" and pretty meaningless.

[Serge]

More like "could make recharging impossible".
I have no interest in a battery that I can't charge cheaply at home. It negates one of the great benefits of an EV, low cost overnight home charging and never having to stop at a "gas" station or being tied into a single "fuel" source or provider.

If I understand the article correctly, these cells support electric and "mechanical" recharging.

[dpeilow]

Indeed, the article contains this diagram:

[vfx]

Big Blue dreams of a big green battery

SAN FRANCISCO - Spike Narayan watched a Tesla electric sports car rocket from zero to 60 mph in less than four seconds and knew batteries would be the next big thing.

“It’s hard to understand you’re not in a gas-powered Porsche,” Narayan said as he recalled the demonstration outside IBM’s Almaden Research Center in the heart of Silicon Valley. “Your head snaps back from the speed.”

The vision underscored the importance of battery power to Narayan and other IBM researchers who led a future-of-batteries conference that ended Thursday at the center.

Scientists spent two days discussing potential new ways to store electricity and chart paths for research.

IBM is focusing on Lithium-Air batteries, which the company said have the potential to pack up to 10 times the power stored in Lithium-Ion batteries commonly found in cell phones and laptops.

The U.S. technology giant and its partners expect to invest approximately $10 million in the project during the next three years.

Narayan said that the time is right to strive for battery breakthroughs.

A Chevrolet Volt car poised for release in the United States has batteries that can power it for 40 miles without help from a gas engine built into the vehicle.

Toyota will soon launch a third-generation of the Japanese auto titan’s popular hybrid gas-electric Prius, sporting even more energy efficiency.

Tesla Motors just recently received a $465 million loan from the U.S. Department of Energy to build an electric family sedan to accompany the Roadster sports car that is the young U.S. company’s sole offering.

IBM believes Lithium-Air could be the next big thing when it comes to providing batteries for those and other such innovations.

Big Blue’s big green project has skeptics, some of whom debate whether consumers will be interested in energy-efficient cars. “Consumers are not willing to pay for fuel-efficient technology if they don’t know the future of fuel prices, or even their own job,” said Daniel Sperling, who co-authored the book ‘Two Billion Cars’ about the challenges of fuel efficiency.

While some electric-car backers are encouraged by the success of a U.S. “Cash for Clunkers” programthat subsidized purchases of fuel-efficient cars by those trading in gas guzzlers, Sperling believes that more needs to be done. “Consumer behavior is a big part of this,” he said. “We need to do our best to align market forces to encourage them.”

Some conference attendees claimed that a lack of guidelines at the U.S. Environmental Protection Agency was leaving car makers free to promise mileage performance that vehicles aren’t likely to deliver on.

Nissan announced its coming Leaf car will get 367 miles per gallon of gasoline, while Chevrolet says the Volt will squeeze 230 miles from each gallon of fuel.

“I would have never announced those numbers,” Nobel Prize winner Burton Richter said of General Motors, which owns Chevrolet. “It was a stupid thing to do.”

Richter and other conference-goers suspected that the performance by the cars may not be as spectacular as the companies claim, which could sour the consumers’ tastes for alternative energy technologies.

Since hydrogen fuel cells aren’t yet practical, Richter said, battery power is the best alternative to oil.

“The stars are aligned between national-security freaks and climate-change freaks,” the Stanford University professor said of increased interest in oil independence. “The world is eager for this stuff.”

For conference speaker Ted Miller of Ford Motor Company’s research division, better batteries go far beyond cars to better-performing devices such as smaller iPods and longer-lasting laptops. “But these things take time,” Miller said.

In the mean time, Miller was just glad to see progress.

“It’s delightful to see 100 miles per gallon,” he said with a smile. “It’s a phenomenal feeling.”

(Grist )

[johnr]

IBM is focusing on Lithium-Air batteries, which the company said have the potential to pack up to 10 times the power stored in Lithium-Ion batteries commonly found in cell phones and laptops.

A minor correction, that should be "10 times the energy stored"... and I disagree that the public would not be interested. Look at how many people are installing solar panels. With a battery like that, the public would go crazy for electric cars!

[JRP3]

With a battery like that, the public would go crazy for electric cars!

If it was affordable.

[Serge]

If it was affordable.

On its surface, there is nothing exotic (and therefore expensive) about Lithium Air chemistry.

[doug]

Lithium-Air Batteries Seen as Hope for Electric Cars - NYTimes.com

[Serge]

Lithium-Air Batteries Seen as Hope for Electric Cars - NYTimes.com

The article seemed "fluffy", as far as details are concerned. On the other hand, I see that Almaden Institute website has [some] presentations posted since last I checked shortly after the conference. H. Zhou's (of AIST) presentation is not online, but Peter Bruce's (of Saint Andrews University) is. Should prove to be some interesting reading...

[vfx]

REPORT: IBM working to develop 500-mile lithium-air battery pack — Autoblog Green