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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."
Recharge in less then 5 minutes?
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Solved by standardized connectors and form factors.
Instead of charging the battery in the car, exchange the empty battery for a loaded one.
Not an absolute requirement by any means. Current cars can do an 80% recharge in half an hour, more than adequate for most people. 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. If you manage to hit the 500 mile range then half an hour to recharge your own body is probably a good idea.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
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.
No, increasing the time to 30 minutes would mean insane profits from your customers being stuck there for 30 minutes with nothing to do but drink your coffee and eat your food.
Also, remember that electric motors are 3x more efficient that gas engines (80% thermal efficiency vs. 25%), so batteries don't need to get parity with gasoline in order to be comparable.
I have natural gas taps in my house. Some people have fuel oil delivered. Anyway, even if a car can be recharged in minutes at a station, it could also be charged overnight when needed.
Ah, but that's the beauty of it: You don't need to know the number of duty cycles.
You exchange your empty battery for a charged battery with the assurance of the fuel station that this battery carries the charge you just paid for.
And if that one's empty, you'll replace it again.
Furthermore, you can insert some electronics to store and display statistics - no need to sell a dumb battery.
Again, a solvable problem.
To be fair, it may represent a different business model entirely.
Gas stations mostly operate on thin margins on the gasoline itself, with the profit center being trying to get people to walk in the door to by some snacks/drink/whatever. Generally only items that can be browsed and purchase comfortably in a minute or so, since the store doesn't want a car consuming a spot more than that.
However, having vehicles that require a lot longer to charge and can be safely recharged without the operator in attendance changes the dynamics. No longer do you have businesses that are places to replenish vehicle range primarily, but you have a wider variety of businesses where they want people to sit around for a lot longer time away from their car. Some may provide metered charging as a way to augment their revenue or recover cost of the service, some even may provide it for 'free' to draw people in the door. You can already see this happening. In my area, there are shopping malls with currently free charging access. There are also restauraunts with metered chargers. A number of employers are starting to mention free charging as a perk, in part to draw people in and in part to show off how 'green' they are.
XML is like violence. If it doesn't solve the problem, use more.
Flywheel storage. Under existing service station forecourts, are massive fuel tanks. Replace them with flywheel energy storage systems (which can be trickle-charged from the grid and discharged very fast if need be), and we may yet be in business.
Flywheel storage are used to augment the National Grid in powering the Joint European Torus, and can deliver many tens of megawatts of power on demand.
http://en.wikipedia.org/wiki/Joint_European_Torus
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.
If your driving needs ar compatible with an EV, then you can get an EV. If an EV can't meet your needs, then you can get a gasoline car.
Exactly.
Your comment is common, and it implies that this is a death knell for EVs, like they're impractical and will fail. Not true, just different strokes for different folks.
I see a lot of EV proponents discounting the drawbacks, and arguing every which way that EVs with just a little bit of improvement will be good enough for nearly everybody. Let's face it, hipsters congregate in dense urban areas where any car is a luxury, and many just can't imagine that some of us actually live a long way away from anything ;-)
Funny thing is, I would need a lot more range to use an EV, but slow charging times would not bother me so much for a secondary car, because many times it would have multiple days to charge ;-)