Posted on 03/13/2009 7:17:40 PM PDT by Reaganesque
Powered up: An amorphous layer (light-colored band at the right) on a crystalline battery material improves its performance. Credit: Byoungwoo Kang, MIT
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A lithium-ion battery electrode described this week in the journal Nature can deliver electricity several times faster than other such batteries. It could be particularly useful where rapid power bursts are needed, such as for laser weapons or hybrid race cars.
Test batteries based on the new electrode--developed by Gerbrand Ceder, a professor of materials science at MIT--can be discharged in 10 seconds. In comparison, the best high-power lithium-ion batteries today discharge in a minute and a half, and conventional lithium-ion batteries, such as those in laptops, can take hours to discharge. The new high rate, the researchers calculate, would allow a one-liter battery based on the material to deliver 25,000 watts, or enough power for about 20 vacuum cleaners.
This level of power output would put these batteries on par with ultracapacitors, gadgets that can rapidly discharge power but can't carry much energy for their size, says John Miller, a vice president for systems and applications at Maxwell Technologies, a manufacturer of ultracapacitors, who wasn't involved in the research. The new batteries would store nearly 10 times as much energy as an ultracapacitor of the same size. The combination of small size and extreme power could make the batteries particularly useful for race cars, he says. (Starting this year, new Formula One racing rules will allow race cars to store energy from braking to deliver very brief jolts of acceleration.)
To improve the batteries, the researchers modified an electrode material called lithium iron phosphate to allow electrons and ions to move in and out of it much more quickly. The advance is based on computer models that Ceder developed in 2004. The models suggested a way to improve conductivity by directing lithium ions toward particular faces of crystals within the material.
To exploit this, Ceder included extra lithium and phosphorus. This helps form a layer of lithium diphosphate, a material known for its high lithium-ion conductivity. He says that ions encountering the material are quickly shuttled to faces that can pull them in, allowing for very fast discharging.
The fast-discharging materials may also recharge quickly, raising the possibility of cell phones that charge in seconds, Ceder says, but this would require expensive chargers. Ric Fulop, vice president of business development at A123 Systems, a battery maker based in Watertown, MA, that has licensed Ceder's new material, says that it could be useful for hybrids or for delivering the power needed for laser weapons. (Fulop notes that A123 is not developing batteries for the latter application.)
Other researchers have already modified lithium iron phosphate to achieve power levels high enough for power tools and for most hybrid vehicles. Indeed, iron phosphate batteries are already being sold by more than one battery maker for such applications. Ultimately, the energy capacity of lithium iron phosphate is lower than that of other lithium-ion battery materials, making Ceder's advance of limited value, says Jeff Dahn, a professor of physics at Dalhousie University, in Halifax, Nova Scotia. This battery is good for acceleration, but not as much for long range. "A real breakthrough . . . would be a new positive electrode material with quantum-leap performance specs" in energy storage, Dahn says.
Very interesting. Thanks!
I better get that powerful laser canon before it is criminalized.
Great! Sign me up for a phased plasma rifle in the 40 watt range. None of these dustbuster phasers for me.
” I like how they save the negative news for last.”
Yes the positive news came first, creating a jolt of interest.
Excellent, I want my zap gun. No need for silencers. No recoil. Fully automatic.
Great self defense weapon against criminals. Looking forward to getting one.
snip
The new high rate, the researchers calculate, would allow a one-liter battery based on the material to deliver 25,000 watts, or enough power for about 20 vacuum cleaners.
So it can power 25 vacuum cleaners for 10 seconds or one vacuum cleaner for 250 seconds, just over four minutes? 33HP for ten seconds in a quart sized package, as usual, no potential for vehicles.
No, there are many applications where it could be used. Particularly in laser or magnetic rail gun weapons that need high amounts of energy for short bursts and then can recharge in several seconds from a traditional power source. They could also be used in conjunction with standard LI batteries in cars for quick acceleration.
Let’s not forget Sharks with Freakin’ Lasers on their Heads!
I would rather have them controlled by a sight mounted on my sunglasses.
If they were set up in an array the short bursts could be as continuous and powerful as the hardware and power source could handle. Theoretically.
Me too. First for the next punk that cuts me off. Then for the gang-banger in the next lane booming sound louder than a Saturn V taking off.
Discharging in 10 seconds is much slower than discharging a capacitor. I guess they would discharge into a set of caps that would then discharge to power a pulse laser.
I once charged up a bank of large motor start capacitors and discharged them all at once across a 1 inch steel rod...it vaporized the rod....in just a tiny fraction of a second. The power level in amps during the discharge was enough to power a small city (for a tiny fraction of a second)...according to Ohms law... This sort of mega power release is the basis for limited area EMP weaponry. I would expect the power for a small EMP pulse to be generated by an explosion that sends highly magnetized material past a coil at tremendous speed...not capacitors.
Yes, and the inherent problem with fuel cells is that they cannot change the amount of energy they are generating very quickly. If you put one in a car with a these new batteries, you could have the power output set at a mid range and you could run off the batteries practically all the time, charging when cruising at a steady pace or stopped and discharging when accelerating. Great for around town.
Might even be nice for a Bonneville Salt Flat run.
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