BBC: Battery that 'charges in seconds'

[Qutzupalotl]

A new manufacturing method for lithium-ion batteries could lead to smaller, lighter batteries that can be charged in just seconds.

Batteries that discharge just as quickly would be useful for electric and hybrid cars, where a quick jolt of charge is needed for acceleration.

The approach only requires simple changes to the production process of a well-known material.

The new research is reported in the scientific journal Nature.
. . . . .

"If transport of the lithium ions was so fast, something else had to be the problem," Professor Ceder said.

That problem turned out to be the way ions passed through the material.

They pass through minuscule tunnels, whose entrances are present at the surface of the material.

However, the team discovered that to get into these channels, the ions had to be positioned directly in front of the tunnel entrances - if they were not, they could not get through.

The solution, Ceder discovered, was to engineer the material such that it has a so-called "beltway" that guides the ions towards the tunnel entrances.


more at link:
http://news.bbc.co.uk/2/hi/science/nature/7938001.stm

[FiveGoodMen]

1. "If everyone in China jumped off a chair at the same time..."

Wait till a whole bunch of people try to charge those at once.

Energy still has to come from somewhere, regardless of how the battery is constructed.

[OKIsItJustMe]

3. "Energy still has to come from somewhere, regardless of how the battery is constructed."

Sure, but…

One of the (perceived) "problems" with EV's is the charge time. People are used to pulling into a station and filling their gas tank in a couple of minutes. They don't really want to wait hours.

If you could pull into the charging station, in your EV, and recharge your battery in about the same amount of time it currently takes to fill a gas tank, customer acceptance would be much better.

[FiveGoodMen]

4. When too many people use their AC on a hot day, power grids are threatened

A battery that holds x amount of potential energy when charged has to draw that energy from the power grid.

Drawing it much, much, much faster puts a much, much, much greater strain on the system.

Blacking out a few states at a time won't do much for customer acceptance.

[OKIsItJustMe]

5. Did I hear you say "smart grid?"

It sure would be handy if a demand spike like that didn't "black out a few states." Perhaps if the grid "knew" that this wasn't a priority demand…

http://en.wikipedia.org/wiki/Smart_grid#Demand_response_support

[FiveGoodMen]

7. Well if we had that at least we wouldn't have the type of collapse that hit the Northeast in '03

http://en.wikipedia.org/wiki/2003_North_America_blackout

That would be good.

But if the grid held back on the non-priority demands and if everyone was trying to run on these new batteries, then the fast-charging wouldn't happen after all.

From the link:

Electrical power cannot easily be stored over extended periods of time, and is generally consumed less than a second after being produced.

How many people are filling their tanks with gas right now? What if they all had these batteries instead?

[OKIsItJustMe]

9. A few possibilities jump to mind

1. The "charging station" has a very large capacity battery of the same type on premises, which it trickle charges from the grid as necessary. This would level the load.
2. Customers learn that "rush hour" may not be the best time to charge, just as they know today that they may wait in line at "the pump" if they attempt to "fill up" during peak traffic times.
3. Electric providers know to expect increased demand at certain times, i.e. "rush hour" and engineer their generating capacity accordingly.

Having given this several seconds of careful consideration, I like #1 most. It essentially resembles the current model of a "filling station" having large tanks which are replenished as needed.

[FiveGoodMen]

11. Agreed that option 1 is the most viable.

[gristy]

13. Yes. My thought too. The "electron station" will need a reserve.

It's own rechargeable battery. It has to be pretty big, but it doesn't have to be mobile.

[wtmusic]

16. Or better: a bank of ultracaps

that could deliver a charge with far less resistance in a short period of time

[OKIsItJustMe]

21. The claim here is that these batteries take and deliver a high charge quite quickly

As far as I know, with today's technology, even "ultracapacitors" need to be much larger than batteries to store the same amount of electric charge.

[OKIsItJustMe]

22. No, you're right, capacitors would probably be better

Rechargeable batteries probably would not stand up as well.

[BobRossi]

6. It would make better use of regenerative power.

Say from regenerative braking systems.

[FiveGoodMen]

8. That would be a good thing. But it has nothing to do with the sudden power demand

that such a battery would create.

[wtmusic]

12. The "sudden power demand" would be spread out

at different times for hundreds of thousands of cars, and most would be recharging off-peak anyway. No problem.

[FiveGoodMen]

14. Here's an experiment you can do at home.

Step 1: Take an ordinary extension cord, cut it, tie the two wires together...

WARNING: In the next step be VERY CAREFUL not to touch those wires!

Step 2: Plug the other end into a wall socket.


Question: What happened to your fuse/circuit-breaker?

Answer: Too much power flowing too quickly through the circuit.


Pushing a car around for hours -- F=MA and the mass is pretty significant -- takes a lot of energy, and it's all going to go through a wire and into this battery in seconds.

No problem? We'll see.

[wtmusic]

15. It will likely take a new electric service installation

for homes that have the charger, but for the grid it's a drop in the bucket. And it's not a short circuit.

[tinrobot]

17. Solution - draw the power slowly and store it for the recharge.

Invent a charging device that includes a bank of capacitors or batteries. The device would take hours to fully charge the capacitors/batteries, but that stored power can then be transferred to the vehicle very quickly.

Charging stations would have heavier duty power lines, but they would also store power so the grid isn't sucked dry.

[wtmusic]

18. bingo. nt

[tinrobot]

19. The charging stations could also put power back into the grid.

These storage devices could also be used as load balancers on a smart grid, storing solar power for night use or balancing out the grid for peak usage as well.

[IDemo]

20. With enough EV's and plug-in hybrids, the vehicles will become the primary grid power storage

http://www.udel.edu/V2G/

What is V2G?

Electric-drive vehicles, whether powered by batteries, fuel cells, or gasoline hybrids, have within them the energy source and power electronics capable of producing the 60 Hz AC electricity that powers our homes and offices. When connections are added to allow this electricity to flow from cars to power lines, we call it "vehicle to grid" power, or V2G. Cars pack a lot of power. One typical electric-drive vehicle can put out over 10kW, the average draw of 10 houses. The key to realizing economic value from V2G is precise timing of its grid power production to fit within driving requirments while meeting the time-critical power "dispatch" of the electric distribution system.

[OKIsItJustMe]

2. Nature news release

http://www.nature.com/news/2009/090311/full/news.2009.156.html

Lithium batteries charge ahead

Researchers demonstrate cells that can power up in seconds.

Geoff Brumfiel

Two researchers have developed battery cells that can charge up in less time than it takes to read the first two sentences of this article. The work could eventually produce ultra-fast power packs for everything from laptop computers to electric vehicles.

Byoungwoo Kang and Gerbrand Ceder of the Massachusetts Institute of Technology in Cambridge have found a way to get a common lithium compound to release and take up lithium ions in a matter of seconds. The compound, which is already used in the electrodes of some commercial lithium-ion batteries, might lead to laptop batteries capable of charging themselves in about a minute. The work appears in Nature this week.

Lithium-ion batteries are commonplace in everything from mobile phones to hybrid vehicles. "They're essentially devices that move lithium ions between electrodes," says Ceder. The batteries generate an electric current when lithium ions flow out from a storage electrode, float through an electrolyte, and are chemically bound inside the opposing cathode. To recharge the battery, the process is reversed: lithium ions are ripped from the cathode compound and sent back to be trapped in their anode store.

The speed at which a battery can charge is limited by how fast its electrons and ions can move - particularly through its electrodes. Researchers have boosted these rates by building electrodes from nanoparticle clumps, reshaping their surfaces, and using additives such as carbon. But for most lithium-ion batteries, powering up still takes hours: in part because the lithium ions, once generated, move sluggishly from the cathode material to the electrolyte.

…

[OKIsItJustMe]

23. MIT Press Release

http://web.mit.edu/newsoffice/2009/battery-material-0311.html

Re-engineered battery material could lead to rapid recharging of many devices

Beltway for electrical energy solves long-standing problem

Elizabeth A. Thomson, News Office
March 11, 2009

MIT engineers have created a kind of beltway that allows for the rapid transit of electrical energy through a well-known battery material, an advance that could usher in smaller, lighter batteries -- for cell phones and other devices -- that could recharge in seconds rather than hours.

The work could also allow for the quick recharging of batteries in electric cars, although that particular application would be limited by the amount of power available to a homeowner through the electric grid.

The work, led by Gerbrand Ceder, the Richard P. Simmons Professor of Materials Science and Engineering, is reported in the March 12 issue of Nature. Because the material involved is not new -- the researchers have simply changed the way they make it -- Ceder believes the work could make it into the marketplace within two to three years.

State-of-the-art lithium rechargeable batteries have very high energy densities -- they are good at storing large amounts of charge. The tradeoff is that they have relatively slow power rates -- they are sluggish at gaining and discharging that energy. Consider current batteries for electric cars. "They have a lot of energy, so you can drive at 55 mph for a long time, but the power is low. You can't accelerate quickly," Ceder said.

Why the slow power rates? Traditionally, scientists have thought that the lithium ions responsible, along with electrons, for carrying charge across the battery simply move too slowly through the material.

About five years ago, however, Ceder and colleagues made a surprising discovery. Computer calculations of a well-known battery material, lithium iron phosphate, predicted that the material's lithium ions should actually be moving extremely quickly.

"If transport of the lithium ions was so fast, something else had to be the problem," Ceder said.

Further calculations showed that lithium ions can indeed move very quickly into the material but only through tunnels accessed from the surface. If a lithium ion at the surface is directly in front of a tunnel entrance, there's no problem: it proceeds efficiently into the tunnel. But if the ion isn't directly in front, it is prevented from reaching the tunnel entrance because it cannot move to access that entrance.

Ceder and Byoungwoo Kang, a graduate student in materials science and engineering, devised a way around the problem by creating a new surface structure that does allow the lithium ions to move quickly around the outside of the material, much like a beltway around a city. When an ion traveling along this beltway reaches a tunnel, it is instantly diverted into it. Kang is a coauthor of the Nature paper.

Using their new processing technique, the two went on to make a small battery that could be fully charged or discharged in 10 to 20 seconds (it takes six minutes to fully charge or discharge a cell made from the unprocessed material).

Ceder notes that further tests showed that unlike other battery materials, the new material does not degrade as much when repeatedly charged and recharged. This could lead to smaller, lighter batteries, because less material is needed for the same result.

"The ability to charge and discharge batteries in a matter of seconds rather than hours may open up new technological applications and induce lifestyle changes," Ceder and Kang conclude in their Nature paper.

This work was supported by the National Science Foundation through the Materials Research Science and Engineering Centers program and the Batteries for Advanced Transportation Program of the U.S. Department of Energy. It has been licensed by two companies.

[GreenGreenLimaBean]

10. This has great potential

Cars could drive up to charging stations and recharge in the same amount of time it takes to fill a tank of gas....To get around the large amounts of power required, new filling stations could have a series of super-capacitors on site in place of underground storage tanks.