Topic: Ultra-High-Power Lithium-Ion Batteries

[Nemesis]

Link to full article

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.)

[Dracho]

In a related article, the same battery could be recharged in 10-20 seconds.  This will also be huge for the hybrid car market.

http://www.foxnews.com/story/0,2933,508988,00.html

Scientists Build New Batteries That Recharge in Seconds

CHICAGO  —  U.S. engineers have found a way to make lithium batteries that are smaller, lighter, longer lasting and capable of recharging in seconds.

The researchers believe the quick-charging batteries could open up new applications, including better batteries for electric cars.

And because they use older materials in a new way, the batteries could be available for sale in two to three years, a team from Massachusetts Institute of Technology reported on Wednesday in the journal Nature.

Current rechargeable lithium batteries can store large amounts of energy, making them long-running. But they are stingy about releasing their power, making them discharge energy slowly and require hours to recharge.

Scientists traditionally have blamed slow-moving lithium ions — which carry charge across the battery — for this sluggishness.

However, about five years ago, Gerbrand Ceder and a team at MIT discovered that lithium ions in traditional lithium iron phosphate battery material actually move quite quickly.

"It turned out there were other limitations," Ceder said in a telephone interview.

Ceder and colleagues discovered that lithium ions travel through tunnels accessed from the surface of the material.

If a lithium ion at the surface is directly in front of a tunnel entrance, it can quickly deliver a charge. But if the ion is not at the entrance, it cannot easily move there, making it less efficient at delivering a charge.

Ceder and colleagues remedied this by revamping the battery recipe.

"We changed the composition of the base material and we changed the way it is made — the heat treatment," Ceder said.

This created many smooth tunnels in the material that allow the ions to slip in and out easily.

"The trick was knowing what to change," he said.

Using their new processing technique, the team made a small battery that could be fully charged in 10 to 20 seconds.

Ceder thinks the material could lead to smaller, lighter batteries because less material is needed for the same result.

And because they simply tinkered with a material already commonly used for batteries, it could be easily adapted for commercial use.

"If manufacturers decide they want to go down this road, they could do this in a few years," Ceder said.

One glitch, Ceder said, would be handling the extra surge of power.

"All of the wiring has to get beefed up," he said.

[Nemesis]

I imagine a laser pistol using lithium AA batteries as "cartridges" each one giving either one 10 second shot or ten 1 second shots.  How many watts per square inch can a human body take? 

[marstone]

it would make the induction charging station more feasable for full electric cars.  Being able to charge in about the same time as filling up your gas tank.

[Dracho]

It'll also be interesting to see how the downhill and braking technologies on hybrids work when the battery recharges in seconds.

For the military applications, that battery hooked to a laser and a gas generator would seem to zap your butt every few seconds.

[marstone]

It'll also be interesting to see how the downhill and braking technologies on hybrids work when the battery recharges in seconds.

For the military applications, that battery hooked to a laser and a gas generator would seem to zap your butt every few seconds.

more practical for the military would be for running the infantry gear.  The in-the-boot charging unit would probably be more efficient with that battery.  Making infantry computer equipment more reliable for longer times out.