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IBM Creates 'Breathing' High-Density Lithium-Air Battery
MrSeb writes "As part of IBM's Battery 500 project — an initiative started in 2009 to produce a battery capable of powering a car for 500 miles — Big Blue has successfully demonstrated a light-weight, ultra-high-density, lithium-air battery. In it, oxygen is reacted with lithium to create lithium peroxide and electrical energy. When the battery is recharged, the process is reversed and oxygen is released — in the words of IBM, this is an 'air-breathing' battery. While conventional batteries are completely self-contained, the oxygen used in a lithium-air battery comes from the atmosphere, so the battery itself can be much lighter. The main thing, though, is that lithium-air energy density is a lot higher than conventional lithium-ion batteries: the max energy density of lithium-air batteries is theorized to be around 12 kWh/kg, some 15 times greater than li-ion — and more importantly, comparable to gasoline."
Your move, range anxiety crowd.
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The summary makes it sound like they've never used air in batteries before. Most small batteries, including hearing aid batteries, are zinc-air. This is why they come with a small sticker on one side - you remove the sticker and give the battery a minute or so to take in air. That said, I don't believe the zinc-air batteries "breathe" like how the article describes, and they're certainly not rechargeable so kudos to IBM.
the oxygen used in a lithium-air battery comes from the atmosphere, so the battery itself can be much lighter.
When the battery is recharged, the process is reversed and oxygen is released
The article was a bit brief, but from this read it seems that as the battery is discharged, it gains mass, but I'm just not seeing how much mass it would gain.
Also, if that thing releases pure oxygen when you charge it, I'm not charging that thing in my garage.
How long does it take to recharge? Current li-ion cars can get to 80% charge in half an hour.
const int one = 65536; (Silvermoon, Texture.cs)
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I have been touting electric cars for years now as the next big thing....this makes me look like less of an eco-asshole :-P
I've been with the "range anxiety" crowd for a while now... the current capacity of electric vehicles has meant you pretty much MUST own a second car, or you'll be renting a "real" car pretty often.
If my car can go 500 miles on a charge? The last time I was riding in a car that went that long without an overnight stop (which could be used for charging) was college. Now that I have actual money? If I'm going 500 miles, I fly. (And even if I was driving, I'd get a hotel room for overnight... straight-through shift driving is something I just don't do any more.)
The thermal energy in gasoline has to be converted to a more useful form of energy (i.e. turning the wheels), the efficiency of this is going to be ~20% for a automobile. The battery is supplying much more useful energy, the efficiency of converting electricity to useful energy is going to be something like 90% (or more). So a battery with the same energy density of gasoline actually has at least 4 times the useful energy of the same size (weight actually) gas tank.
According to Wikipedia: http://en.wikipedia.org/wiki/Energy_density#Common_energy_densities The energy density for gasoline 47.2 MJ/kg and Lithium air battery 9 MJ/kg. If five times less is "comparable" I wouldn't mind the li-air car cost of $4000 which is comparable to a regular gas car.
If this was coming from somewhere else, I would be more swayed by your battery histrionics point. But, IBM does not frequently dish out bullshit results for publicity.
the investors in Big Oil make money, not oil When other energy sources become available, they will invest in those. they know we're coming off of peak oil production and they want their money flow. they just want their big piece of the action.
According to the video we won't see these batteries in cars until "2020 or 2030". That seems like a long way off considering the summary says "demonstrated a light-weight, ultra-high-density, lithium-air battery" As far as I can glean from the vague articles is that all IBM has done is demonstrate the fundamental chemistry on a supercomputer. As far as I can tell they have not actually built a working battery of significant size and definitely not one of a size that would power a vehicle. There have been may technologies that work well in pristine laboratory environments but fail when they attempt to scale and/or have to deal with the dirty environment. Sure the battery may even work on a small scale when exposed to pure oxygen but how does it deal with the other elements in the atmosphere? Take a look at this. I do not see where IBM shows how that deal with any of these issues.
You don't want too much oxygen, especially since it's flammable.
"When information is power, privacy is freedom" - Jah-Wren Ryel
Remember that in the future the idea will be to charge your car in the car park or at home, not just on the road.
Actually, in the future, it is likely that you will be able to recharge while you are driving. Here is how it will works: automatic lane control and braking systems will enable cars to travel in "platoons", with just a few inches between cars. This will greatly extend the range of your car by reducing air resistance, but the cars can also be magnetically coupled, so they can push and pull each other. So if you are on a long trip, and your battery is low, the computer in your car can automatically negotiate with other cars in the platoon and purchase power. You can use this to coast without draining your battery, or even run your engine in reverse and recharge your batteries as you drive.
There is one issue with these 500mi batteries I can think of, how do you charge them quickly? if you assume it takes about 30KW do push a prius sized vehicle at 50mi/hr then a 500 mile battery would mean about 300Kw/hr storage. I'm not sure if that is what is here or not, but let's assume yes. To charge a 300kW/hr battery in ten mites would require a 1.8MegaWatts connection for every car at the "pump". Sounds kinda dicey. do you really trust that every car pulling up is maintained so well that a bad connection would not explode if you put a megawatt into it?
Even swapping out batteries and charging them off line would not actually decrease the demand. If a "busy" interstate gas station typically had 5 people/ ten minutes filling up all day long then whether you change batteries or not, it is still a 9mega watt station. If you could charge them overnight when they were closed, then it is still a 4.5Mwatt station to maintain a ten minute pit-stop time.
So simply building a large battery does not entirely solve the range problem with electric cars.
What about charging them at home? same problem if everyone is your apartment building wants to go 500 miles every day.
But that's just it. most people in your condo are not going to go 500 miles every day. Electric cars still make sense for commuters rather than long range travelers. Commuters drive a tenth of that, so the power demand is a tenth. this makes charging them at home sensible.
so this is a big advance but it is still does not solve the 500 mile recharge problem.
Some drink at the fountain of knowledge. Others just gargle.
If this really is the 'next big thing', does this mean that Lithium will soon replace Oil as the 'natural resource to have'? At least the lithium could be easily recycled...
From the linked video it states that a car sized batter will probably not be available until 2020 or 2030. I think the subtext to that is really "We don' think this technology is actually viable and hope that some new technology will be found within the next 8 to 18 years that will make our research moot but give us money now anyway".
where do you get this 200Wh/mile? Wind resistance and storage conversion (in and out) inefficiecincy are the dominant factors for highway travel. wind resistance is pretty much set by the size of the car's crossectional area. So irrespective of how light or efficient you can make the engine you are not going to beat that. I estimate it take 30KW to push a honda accord size car at highway speed.
Some drink at the fountain of knowledge. Others just gargle.
You are assuming that EV will simply replace the current engine and fuel tank with an electric engine and battery... This is not what has to happen.
Currently engines are big and heavy so you only have one. You then have to transfer the rotational energy of the engine to the wheels. But Electric motors are very light and tiny. So why not have 4?
Put a small electric engine in each wheel and you eliminate the entire drive train... no more drive train losses and EV's are back up to 90%.
Your 72% efficiency only applies to ICE cars that have been converted to EV's.
Direct current flows through the entire cross section, so area counts. Alternating current induces forces which push the current towards the outside. The dimensions where this skin effect is strong enough to consider depend on frequency. For 60Hz, you can ignore skin effect for currents less than about 100A.
Not big on chemistry, are you? Oxygen is not flammable. It is the opposite of flammable. Flammability is the property of being combinable with oxygen in such a way as to produce flame. O2 does not combine with O2.