Gloves and Heatable Mobiles

While waiting out in the open for the tram on my daily commute I like browsing the web and reading my favourite blogs on the mobile phone. Not so these days, however, it's just not a lot of fun in sub-zero temperatures. So I prefer wearing gloves and keeping my hands in my pockets. In noticed, though, that the battery gets a bit warm while surfing if I can't resist which at least helps a bit. So what about a little built in heating at the back of the mobile? Yes, the battery would drain faster but it would be usable in sub-zero temperatures. Yes, I am only half joking here, but I am not quite convinced it's just a stupid idea. I wonder why Nokia, coming from a Nordic country never had the idea. Well, maybe with the temperatures there even heatable mobiles wouldn't help in winter :-)

Comments

[Ajit Jaokar]

one more use for a mobile phone. Dont forget to carry it with you to Oslo! ha ha!

[Alexander D.]

Let's suppose the battery is 1000 mAh at 5 volts voltage. If the heating device is connected to the mobile phone over USB On-The-Go, thus drawing 500 mA of power, then there is enough energy to do the 2.5 W heating for two hours theoretically, or in practice it can mean an hour of heating and some phone usage.

But the next question is, what kind of heat can you get from 2.5 W? 2.5 watt hours is about 2150 calories, which mean that this energy can heat 2.15 liters of water by one degree Celsius, or 215 ml of water by 10 degrees (but don't forget that this heating will take a whole hour). That sounds minuscule, but then how do they sell those USB cup heaters as, well, heaters? I have never owned one, so I can't judge. Maybe they actually cheat and draw much more than the allowed 500 mA (they definitely don't enumerate on the USB bus to request more power).

At least you have a viable way to actually realize your heating idea - using USB On-The-Go. But I guess not all phones will be able to supply whole 500 mA of power to the USB port.

[Alexander D.]

Gotta buy one of these and test: http://www.dealextreme.com/details.dx/sku.30367 :)

[mobilesociety]

haha, yes, that is what I am looking for! Now I need a small power source that can drive them for 30 minutes a day :-)

[mobilesociety]

Hi Alexander,

Thanks for commenting!

When I hold the phone in my hand and use it to surf the web I can feel the heat in my hand after a couple of minutes generated I guess by using the battery. So I think at the end of the day while I wait for the tram for 10 minutes or so, I could spare the energy as I plug the phone into the charger everyday anyway :-)

Cheers,
Martin

[Alexander D.]

In the comments for those heated gloves one guy says that he is using this power source to power them:

http://www.dealextreme.com/details.dx/sku.26479

This particular power source will require you to charge AA batteries, which is a bit of a hassle in comparison with charging of a mobile phone. But I'm pretty sure that you can find a lithium-based USB mobile power source on DealExtreme or a similar shop of you want. However, be warned that cheap Chinese lithium batteries are know to explode from time to time.

Actually, that guy from the comments uses two of those power sources in combinations along with a more powerful set of gloves (that requored two seperate USB ports):

http://www.dealextreme.com/details.dx/sku.17299

But I must say that electric portable heating looks more like a geek toy in comparison with chemical heating pads:

http://en.wikipedia.org/wiki/Heating_pad#Chemical

[Alexander D.]

Look what I have found: http://usb.brando.com/2-in-1-usb-mini-hand-warmer_p01340c050d015.html

[mobilesociety]

Hi Alexander,

yes we are getting close now! And all in a mobile phone now please :-)

Cheers,
Martin

[Alexander D.]

If I were you, I would actually buy the latter device to test the viability of such heating (as it delivers the same amount of heat as a mobile phone would do).