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Recharge Batteries in 30 Secs
An anonymous reader writes "NEC has developed organic radical batteries
which are recharged in 30 seconds. Good news, they won't (probably) cost more than the current NIMH batteries." Why is it that I'm not holding my breath to have this technology in a laptop?
April 2, 2004 (TOKYO) -- NEC Corp has developed a battery that can be recharged only in 30 seconds, company sources said. Called an organic radical battery, it can be recharged to the same level of power as that stored in nickel-hydrogen cells, which are widely used in digital cameras, portable MD players and other electronic devices.
It takes only about 30 seconds to recharge the battery enough to allow 80 hours of continuous operation of an MD player, compared with around an hour needed by conventional rechargeables, the company claims.
Because of its ability to recharge faster, the new battery, which stores power in a special resin, is expected to make radio-controlled toy cars, shavers and other products much more convenient to use.
The battery can also discharge power in a short time, making it useful in applications requiring a large amount of power.
NEC believes the battery can be used as an emergency power source for computers in case of blackouts as well as in hybrid cars driven by a gasoline engine and electric motor.
The company plans to convert existing production facilities into ones able to manufacture the new product. The company expects the price of the new battery to be about the same as nickel-hydrogen cells when mass production starts, since it does not contain any expensive materials.
NEC is also developing a recharger for the battery that can be used at home as well as working on a way to prevent excessive discharge of power from the cell.
The company will initially try to commercialize the technology for using the battery as an emergency power source for computers, according to sources at NEC.
You can see a picture of it here:
r o/
http://www.nni.nikkei.co.jp/FR/TNKS/TNKSHM/newp
my laptop battery is a 4400 mAh at 14.8 V
/T
4.4 Ah * 3600 sek *14.8 -> 234432 Ws
(Whow a palindrome number... coool)
divide this at the recharge time
30 sek
~ 7.8 kW
I live in an appartment.
My outlets cant handle that much..
+ Needs heck of an transformer to handle that effect.
Warning: This sig contains a small bug. ==> *
Found an old press release from '01 on NEC's web site documenting the discovery of this battery technology.
With this latest (today's) press release it sounds like they're finally ready for product.
Now, take the square of the charging current and multiply by the internal resistance. This gives the heat dissipation in watts.
The article gives no real numbers, but let's assume the battery can supply about 5 amp-hours. To get a full charge in 30 seconds, you would need a charging current of 600 amps (!!) Heat dissipation would be 360000 times the internal resistance of the battery -- in order to dissipate fewer than 10 watts the internal resistance would have to be less than 0.000028 ohms.
At 0.000028 ohms, and a made-up terminal voltage of 7 volts, you could draw 250000 amps out of such a battery when shorted. Jesus Christ. But those numbers came out of my ass. We need real values...
http://www2.electrochem.org/cgi-bin/abs?mtg=012&ab s=0186&type=pdf
Abs. 186, IMLB 12 Meeting, (C) 2004 The Electrochemical Society, Inc.
Organic Radical Battery:
Transition-metal free Lithium-ion Battery
Kentaro Nakahara, Jiro Iriyama, Shigeyuki Iwasa, Masahiro Suguro and Masaharu Satoh
Fundamental & Environmental Research Laboratories
NEC Corporation
Hmm, they may have some competition on the speedy recharge front, Moore improvements yet?
350 F, 2.5 V UltraCapacitors in D cell size from Maxwell Technologies.
I saw no mention of the level of heat generated when charging a battery this fast. I haven't worked out any equations, but I was under the impression that there was a certain amount of heat generated per unit of time when charging / discharging batteries.
That depends on the efficiency of the charging process in the battery.
The heat generated is the main limit on charging rate, so I suspect that these puppies have VERY little internal loss when being charged.
The result will be that even when packaged you won't have a lot of problems with charging heat. If they don't get hot enough to damage the "organic resin" in their own guts, your nearby circuitry should be safe.
This also implies low losses for the total cycle. That will be very good for the automotive application. As will the lack of anything rarer than Nickel in their construction.
Nickel-cadmium would have been much better than lead-acid for automotive starter batteries - but that never took over for that service. That's because, if you wanted to put a NiCad starter battery into every car in service even back in the '60s there just wasn't enough readily-minable cadmium reserves known to do the job. It only appears in nature as an impurity in zinc. (So don't even think of making enough NiCad batteries to replace the engines).
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Not necessarily; there are some practical problems with this kind of charger. Consider that a typical AA NiMH battery has a charging capacity of about 2 Ah at a voltage of 1.2 V. That's 2 Ah * 3600 s/h * 1.2 V = 8640 J. To charge that in 30 seconds, you need 8640 J / 30 s = 288 W, and that's assuming no losses anywhere. If you want to recharge 4 batteries at a time, you'll need a charger that draws 10+ amps of 120 VAC. A single D battery can have a capacity of up to 11 Ah, so you'd need about 1600 W to recharge one in 30 s. That means that a dual battery charger would draw over 25 amps at 120 VAC. Since most wall sockets are only rated at 15 amps, you'd need a dedicated circut for your charger! It's not an insurmountable problem, but it would make this style of battery a bit less practical.
There's no point in questioning authority if you aren't going to listen to the answers.