Originally Posted by David Teeghman at Discovery News

Analysis by David Teeghman
Tue Jun 22, 2010 01:40 PM ET

The most consistent complaint I ever hear (or make) about smart phones is they eat up power like a fat kid eats candy. But a new development in how to manufacture rechargeable batteries for portable electronics could allow batteries to hold ten times more power than they do now.

Researchers at MIT found that using carbon nanotubes for one of the battery's electrodes hold much more energy than the current breed of lithium-ion batteries. The experimental batteries use layered carbon nanotubes as the positive electrode and a lithium titanium oxide as the negative electrode. The batteries deliver power at the high-speed rates of capacitors while being able to store more energy than even the best lithium-ion batteries available today.

The carbon nanotube electrodes also proved their longevity. After 1,000 cycles of charging and discharging a test battery, there was no detectable change in the material's performance.

That's good news for anyone with an electric device that runs on batteries, your humble blogger included. I have to charge my Android phone each night just to get through the next day. If these batteries come to market, my little Droid Eris could last for days without a charge.

But that's still a big if. The electrode material was produced by dipping a substrate into two different solutions, a pretty time-consuming process. One of the researchers leading the project, MIT professor of chemical engineering, Paula Hammond, says her team may have a solution. Hammond suggests that the process could be modified by spraying the alternate layers onto a moving ribbon of material, a technique now being developed in her lab.

Until then, I'm stuck charging my smart phone every night.

Originally Posted by cjp (Post 898550)

Well it has indeed been so, that phone hardware keeps getting faster and faster, while battery tech has stayed the same. I would also welcome this new battery.

Got any links to any of this, btw?

Originally Posted by geneven (Post 898566)

The easiest immediate way to revolutionize the amount of available battery power would be to add some sort of capacitor to a device so batteries could be swapped without interrupting the power supply.

Originally Posted by geneven (Post 898566)

The easiest immediate way to revolutionize the amount of available battery power would be to add some sort of capacitor to a device so batteries could be swapped without interrupting the power supply.

Originally Posted by ktchiu (Post 898558)

I'm doubtful that we'll see such a huge leap in battery life in future devices. The more power available means beefier and more power-hungry components. Besides, I feel like I've seen news like this for the past few years but havent seen any major changes.

Originally Posted by gerdich (Post 898599)

On laptops you can do that with hibernate:

You go into hibernate.
You exchange the battery.
You continue working where you stopped!

Originally Posted by gerdich (Post 898599)

On laptops you can do that with hibernate:

You go into hibernate.
You exchange the battery.
You continue working where you stopped!

Originally Posted by geneven (Post 898608)

I just want something to keep me from having to reboot while swapping batteries.

It seems like such a simple concept -- why doesn't hardware to do this with the N900 already exist?

It's basically like in-air refueling.

Originally Posted by ndi (Post 898651)

It does, N900 can swap batteries without rebooting if you are near a wall charger or have an external emergency pack.

Originally Posted by geneven (Post 898672)

I took out the battery and replaced it with another one. While I was doing so, my N900 rebooted.

Originally Posted by zimon (Post 898686)

There is a thread here somewhere where is instructions how to do it. MohammadAG or some of those hardcore hackers did it. It was not very convenient way because you have to have external power through microUSB additionally with you as well as the extra battery to do this on a road. Some services has to be halted and BME tricked to this 20s lasting special mode and so on.

Originally Posted by pisthpeeps (Post 898587)

I have always maintained and will maintain that unless they add powdered viagra as one of the ingredients, batteries would not last longer.

Originally Posted by zimon (Post 898686)

Overall I am not sure we want more capacity into batteries, if it will mean more radiation sent from our mobiles.

Originally Posted by kureyon (Post 898828)

:confused: Please explain how a bigger capacity battery affects the radiation put out by the phone?

Originally Posted by kureyon (Post 898828)

:confused: Please explain how a bigger capacity battery affects the radiation put out by the phone?

Originally Posted by zimon (Post 898686)

I already use 2400 mAh daily on N900 and I do not know how much of it is absorbed by my body via radiation and what will the long term effects be.

Originally Posted by TiagoTiago (Post 898917)

I think he imagines that having more energy to spare you will use the device more often and more intensivelly, and consequently use the functionalities that emit EM radiation more.

Originally Posted by zimon (Post 898993)

and later decide what to keep and what not.

Originally Posted by Joseph.skb (Post 900512)

Anyone working on solar panel rechargeable batteries? Like the handheld calculators have? Solar panels are everywhere nowadays, so why not on our mobilephones since we double it as a GPS on our dashboards.

Originally Posted by Joseph.skb (Post 900512)

Anyone working on solar panel rechargeable batteries? Like the handheld calculators have? Solar panels are everywhere nowadays, so why not on our mobilephones since we double it as a GPS on our dashboards.

Originally Posted by Joseph.skb (Post 900544)

With solar panels now finding a more common spot on residential roofs and other places never before, I'm sure the technology for simple mobilephone battery could be improved. If I'm not mistaken it was also mounted on the Mars rover.

Originally Posted by ndi (Post 900449)

All around you there's EM radiation in the order of watts. There is enough to power a radio from the antenna alone if it's big enough. No effects have been observed this far, aferage lifesoan continues to grow in spite of EM, chemical, biological, superbug and whatnot pollution.

While high EM has been noted as a possible cancer factor, we're talking people living under power lines, which took in equivalents of hundred of watts hour. The phone doesn't exceed 4 W under the worst conditions and not for 24 hours for decades.

Even so, the emissions of you phone is a drop in the bucket, considering that in that area you have several APs, GSM, (several networks), a few tens of radio stations, a few TV stations, walkie-talkies from taxis, satellite coverage, power line hum, EM from electronics and PCs, lighting, space humming, and all kinds of other stuff all over the spectrum.

Not to mention hight energy stuff from the sun and ionizing stuff from space.

Don't let EM spoil your N900.

Originally Posted by ossipena (Post 900462)

it would require so much time to filter what is good to keep and what not that it will be completely useless....

Originally Posted by zimon (Post 900717)

But cellular phone radiating EM @ 2W one inch from your testicles or ovaries (or brains) several hours a day may cause damage.

Originally Posted by zimon (Post 900717)

Made by evolution, we are capable to some extend to tolerate sun light and other "normal" natural EM radiation

Originally Posted by ndi (Post 900609)

Wrong problem. Sun delivers about 900Wh per sq meter in a sunny day. That's 100x100 cm, or 10,000 sq cm. That gives about 90 mWh per sq cm. A phone that's 10 by 7 makes for 70 sq cm, or 6300 mWh, or 6 Wh.

N900 battery is 1300 mAh by 4V approx, so 5200 mWh, about 5 Wh roughly.

Math is nice but in real life you need: charge disspation that's around 20 percent, solar cell efficiency that's about 20 percent, 29 for the really cool stuff (remember, it works only with a limited spectrum).

So that's a 6-7 Wh battery from a panel that gives 6 W by 30%, or about 2Wh.

Originally Posted by Joseph.skb (Post 900923)

That's considering charging up a totally empty phone battery. Also in handheld calculators, it's an ongoing process and you could use artificial light, instead of the sun only, right?

Originally Posted by ndi (Post 900609)

It's not a matter of perfecting it. Solar cells have a theoretical eficiency of 29 percent. Sun delivers 1366 Wh per sq meter, but likely not on your latitude. So, basically, you need bigger sails.

And I haven't even tackled clouds, pollution, angle, heat disspation of electronics, variations of light flux, all of which kill figures and destroy batteries.

Originally Posted by Joseph.skb (Post 900923)

That's considering charging up a totally empty phone battery. Also in handheld calculators, it's an ongoing process and you could use artificial light, instead of the sun only, right?