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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?
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.
30 sec to charge--but how long do they last?
Not only at the laptop but that would be really usefull at cellphones and nobreaks (!?).
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 mean so I can even get first posts when the power is out?
Though I'm curious with something...
Will this be plagued by the Mysterious Memory Effect of Rechargeable Batteries?
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I don't know much about batteries but there is a certain number of charging cycles the rechargable batteries can handle and after which they die(or performance becomes poor). I wonder how they address this issue.
It sounds like a slow discharging capacitor.
One of the nice things about current batteries is that you can't get them to discharge very quickly. Shorting these out might cause excessive heat issues.
NEC is ... working on a way to prevent excessive discharge of power from the cell.
So, it can be used to discharge a great amount of power, but the trick is keeping it from doing so when you don't want it to!
I wonder what the polerisation and memory effects will be though. Most rechargable devices are pretty good (have acceptabl life times) when new, 6 months in the battery usage level has falled to almost unacceptable levels. As an example Sony only waranties batteries for 1 month! If they offer 80 times more storage but die off to 1 times storage in 6 months, this would infact be worse, because devices would be made to "use" the extra power.
James
The article states it is good for Hibrid cars what about electrical ones. I thought a Major problem with electric cars is the time it takes to recharge thus making them impractical in long drives.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
And also how long will the batter life last? I don't wanna change batteries on my cellphone/laptop more than I havta change my underwear.
Also, if this thing catches on, could this be used in electric cars, maybe as the 'oil for the new millenium'? All we could have to do is charge every once in a while, and change batteries every weekend.
If we assume that these batteries have a capacity of 1000 mah, which seems like a reasonable figure since they say they can power an MP3 player for 80 hours, then charging it in 30 seconds implies that during the charging process it is accepting 120 watts.
a) That's not going to be any tiny little wall transformer doing the charging.
b)I sure hope they have the safety and quality assurance issues worked out, because if it doesn't shut off at the exact instant when the battery is fully charged, that 120 watts is going to go somewhere.
It might not be much more dangerous than a firecracker but I suspect it could be pretty dramatic.
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If you've ever had the misfortune of keeping a server up and running while there is major construction going on nearby, you know you can get multiple blackouts of varying duration.
I like to use a UPS to support a server to the last safe second with enough time for an orderly shutdown... but I can't, because I need to know the UPS will last through at least two consecutive blackouts without time to recharge.
Now, with a 30 second recharge, servers under my care could survive twice the blackout duration without increasing the risk of a sudden shutdown.
Consider this quote:
NEC is also developing a recharger for the battery that can be used at home
if it was electricity, wouldn't the creation of a recharger be trivial?
Somebody mentioned heat generation. What about other issues regarding the current? If that much energy were to be drawn from a single power socket in my house in 30 seconds, something would break. Even if it had wires thick enough and some cooling unit for the battery, a fuse would break. How do they deal with this?
Pretty much anyone using rechargeables has at least one extra set so that there's always a fresh pair to swap to when the ones you're using runs out. In that scenario even halfing the recharge time doesn't matter a bit.
Actually it's vs 1 HOUR so it's a factor of 120 reduction (as others have pointed out).
The real point, though, is that they've got the charging time down to less than the time it takes to swap in a fresh set of batteries. So no need to swap any more. Just do a "pit stop" with the fat electric cord in place of the fat pump hose. B-)
(Unfortunately that won't work for a REAL car, which will take a bit longer to charge even if the batteries are capable of better. You're looking at something like a thousand megawatts to charge one of those in a minute. Even if you included a small nuke plant at each filling station, the mag fields around the charging cables might bend the sheet metal. B-) )
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liquid helium isn't a good coolant, becuase it's heat capacity is very low. Liquid nitrogen is a much better coolant, and it's also much cheaper. Besides, that battery might not even work at 77k, much less at 4k.
what sig?
I'll point out that home circuit breakers blow around 10 to 15 amps, so it would be physically impossible to run such a charger off a normal house circuit (and illegal and dangerous if you modified the fuses to allow it).
i remember readng an article once that said if battery technology had advanced over the last 50 years as fast as electronics has (smaller/more power) that by today, a battery the size of a watch battery would be able to power your house.
its nice to see any kind of advancement in the powercell area
180W can be over 100C [hint: an 80W Athlon can hit over 100C].
That may be bad for a battery to be running that hot.
Someday, I'll have a real sig.
Thus the battery holds about 1.2 * 3600 * 1.2 = about 5KJoules.
90% charge efficient means 500Joules as heat.
E = c * m * delta_T
where c = specific heat capacity, m = mass, delta_T = temperature change.
According to Sony, a AA battery is 30g. I don't know what the specific heat capacity of a battery is, but metals are between 0.1 and 0.9, and water is 4. Lets assume it's 1.0 J/gK.
delta_T = E/c*m = 500/(1.0 * 30) = 16 celcius.
That's about 30F for those of you who like odd units. Not such a big deal.
Of course the 90% number is drawn out of the air.
The concept is great, but this is a potential problem with widespread use. They say their first market is Uninterruptible Power Supplies. The short recharge time is great, except the load during that short time will be tremendous.
Your servers draw 100 amps max? When the power comes back on and all your batteries need to recharge at once, expect a serious spike. I'm not an EE, but if it takes 30 seconds compared to 8 hours, that's 960 times faster, which means 960 times the load per unit of time.
Accountants as hosting companies will cry every time the power flickers, as the demand charges shoot up 800%
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All these assumptions are made presuming that the battery will be recharged by a convential current flow recharger. There is nothing that suggests that the charging isn't done with some electric/magnetic field mechanism instead (read: alignment of magnetic domain, redistribution of charge in a lattice, etc...)
ok, a couple of things.
Standard household breakers are rated at 20 amps, but they would configure these to use less than that. Also, your ovens, old microwaves and driers (some washers as well) have their own ciruit from the amount of current they draw. In a company that has servers that draw a lot of current, they are running special thick wire that supports extra current.
Accountants crying:
As long as the power isn't off for too long, the demand won't shoot up much. If the power is off for a second, it will take a milisecond or less to recharge. So it will NOT drive up the electricity bills any more than they were. Where this might be a problem is in tripping the local area power grid from too much load. We need a Power EE to answere that one.
Where this also might be a problem is what happens when you have these things in a UPS and a generator for extended power and a few aren't fully charged. The generator will crap out pretty quickly.
As to heat created, The amount of heat created will be equal to Volts*current-(Amount absorbed into the battery). Efficiency will be (Amount Abosorbed)/(Volts*Current). So if it has a high efficiency, there will be very little heat released.
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Hmm. Imagine these become popular as UPS devices (computers, buildings, etc). Then, there is a huge blackout that drains them down. At that point, the power comes back on.
Suddenly, there is a massive surge far greater than the power usage before the power outage as all these UPS devices suck down power trying to recharge in 30 secs.
Wham! There goes the power again. Rinse. Repeat.
Synergies are basically awesome, and they're even better when you leverage them. -PA