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

 

[Serge]

Lithium Air batteries for Model T?

http://www.teslamotorsclub.com/news...otors-inc-will-take-serious-look-ontario.html

Battery technology, he added, is advancing at an unprecedented rate. "We're going to see things we'd never dreamed of."

Musk cited a new battery chemistry called lithium-air. "It's got 10 times the energy density of the battery packs we're using today, and when that technology comes to market – it still has a lot of challenges to overcome – it will have a 2,000-kilometre range."

Is there any more detail on this?

 

[stopcrazypp]

http://www.teslamotorsclub.com/news...otors-inc-will-take-serious-look-ontario.html


Is there any more detail on this?

I think Musk was just mentioning it since it was in the news. Lithium Air is still quite far from practical use. The more advanced batteries Tesla is planning to use are still laptop cells (albeit more energy dense ones).

 

[dpeilow]

Serge,

Maybe he read your multiple posts on it :wink:.

 

[Serge]

Maybe he read your multiple posts on it :wink:.

An intriguing thought, indeed However, I will speculate that JB got exposure to some interesting developments at IBM's Almaden Institute in August. I am most interested in Zhou's (from AIST) presentation, but it's the only one not posted online. Inquiring minds want to know!

 

[TEG]

Battery 500 Project Charged Up over All-Electric Cars - Technology For Change

 

[Tdave]

That article is yet another one that mentions the energy density of batteries compared with gasoline. I really wish that comparison always took into account the whole system, comparing the weight of:

1) Gas tank full of gas, transmission, engine, exhaust
2) Battery, PEM, gearbox, motor

The weight comparison would be closer. An engine+transmission is much much heavier than the motor+gearbox, for example.

 

[Serge]

That article is yet another one that mentions the energy density of batteries compared with gasoline. I really wish that comparison always took into account the whole system, comparing the weight of:

In addition, due to at least factor of 3 better energy efficiency than gasser, an EV needs to store at least 3 times less energy on board to go the same distance.

 

[Norbert]

In addition, due to at least factor of 3 better energy efficiency than gasser, an EV needs to store at least 3 times less energy on board to go the same distance.

Just to show how inadequate "direct" comparisons between gas and electric are:

One could compare miles per kg, which for electric cars would be the range devided by the difference in weigth between a fully charged battery and an empty battery.

 

[Norbert]

The article in the original post mentions that

Capacities as high as 855 mAhg-1 (based on the total mass of the cathode plus the additional mass of O2) have been achieved

However, it wasn't really clear whether that was an experimental value which would translate to actual battery performance.

This article from June 7th, 2009, however mentions a "prototype", which more directly suggests that these are real-world values:

Air-lithium battery in the works?

Bruce says a prototype (400 milliamp hours per gram) has already beaten the capacity-to-weight ratios of small conventional lithium batteries by a factor of eight, and says a 10-fold improvement is still attainable.

400 mAh/g translates to about 1000 - 1200 Wh/kg, which is in fact already a value about 8x that of current batteries.

 

[Norbert]

The new ARPA-E list of grant-supported research projects has many interesting entries:

Department of Energy - ARPA-E Home (Don't miss the table at the bottom)

In this list of research projects:

Department of Energy - ARPA-E - Research Projects

the section on "Energy Storage" contains this metal-air project:
(Not sure if that means "Lithium-Air", but promises a comparable energy density.)

Sustainable, High-Energy Density, Low-Cost Electrochemical Energy Storage - Metal-Air Ionic Liquid (MAIL) Batteries

Arizona State University (Tempe, AZ), in partnership with Fluidic Energy, Inc., will seek to develop a new class of ultra-high energy new metal-air batteries using advanced ionic liquids. With a target energy density of 6-20 times that available state-of-the-art Li-ion batteries and at < 1/3 the cost, if this project is successful it will create a gamechanginggame changing new battery technology that will enable rapid and widespread deployment of long range, low cost plug-in hybrid and all-electric vehicles, shifting U.S. transport energy to the grid and drastically reducing U.S. oil imports.