Nokia Solar Charger

[Robvix]

Hi
I am trying to build a solar charger for a Nokia 3210. Does anyone know if this is possible?

I have looked at other posts on this site today and have learned that the charging input voltage needs to be a minumum of 5.2v approx, but I would like to know what the minimum required current is?

I have built one that will charge a 3210 for 10 minutes or so, but after that the phone display reads 'not charging' - I suspect the voltage is too low (currently using a panel that delivers 4v).
Thanks
Robvix

[Robvix]

To put it another way, what is the minimum charge current required and are any special components required in a non solar charging circuit, or is it just a length of wire connecting the power to the battery?

[sergo_zmeia]

Very interesting idea...never came to my mind..so some info for U...supply voltage must be 5.7V...bout current be sure U can supply 100mA...thats enough I thing...post some results...Good luck!
Sergo_Zmeia

[Robvix]

Thanks...I've ordered an extra solar panel, that added to the one I've already got should do the trick then - I'll let you know how I get on. I know they use such chargers in remote (often 3rd world) places, but for me, it will be useful for the caravan (often no electric).

[momagic]

good idea! good luck!

[cjard]

funnily enough, the standard nokia chargers list an output that is 3.7 volts, with the battery being 3.6 volts, this would be sufficent to charge it. however, looking at the battery charge test screen (20 or 21 in net monitor) it can be seen that the standard nokia charger pulses at somewhere above five volts. i have a few nonstandard chargers (cheapo things from the local market) that put out a steady 4.8 ish kinda volts..

the phone's battery typically rises to somewhere between 4.3-4.5 volts to become fully charged, so i dont know why the batteries only list 3.6v.. they typically only get down to about 3 volts before the phone switches off

suffice to say, thata considerable amount of technological effort has gone into charging your phones battery.. pulse rates, current and temperature are all continuously controlled by the phone, so you shouldnt have to worry about feeding it some spot-on voltage.. they should be able to cope with 6 or 7 volts.. beyond that, dissipating the heat generated from sapping up the extra volts becomes something of an issue.. so boost your panel a little, maybe use 2 in series, plus a small resistor.

switching on netmonitor and looking at screen 20 (or 21) would be of bebefit too

[deadspot]

wow very interesting info 10x cjard

[THE INSAAN]

good luck robvix, and xclnt idea and i hope you manage to make a good solar charger

[Robvix]

Thank you all for your help. I can report that the extra panel was all that was needed - it charges fine from two 3 volt solar panels wired in series (so 6 volts) when placed in the sunshine.

So now I spend every sunny day possible on a sunbed with my mobile, both of us getting tanned and re-charging our batteries...does anyone know anything about facia sunblock?? :smile:

[Donutface]

woah

really neat, you should sell em on ebay :D

[momagic]

does anyone know anything about facia sunblock?? :smile:

:lol: :lol: :lol:


woah

really neat, you should sell em on ebay :D

good idea! he can make his first million (remember send off for a patent!)

[warren]

great idea man..

aside from the voltage output and current rating, is it possible that PWM charging is also involved? i supposed that is why wallchargers have some sort of circuitry not just rectifier/regulator circuit... (else we can use ordinary dc adaptors???)

just a thought, hope it helps at least...

:???: :???: :???:

[User32]

so, all that's needed are 2 solar panels? was that so easy?
will it work for Li-Ion 3.6V?

[Mardu]

funnily enough, the standard nokia chargers list an output that is 3.7 volts
I measured the voltage of my charger (3.7v written on it) and it gave about 8 volts.

[danwood76]

Inside the phone there are regulators and control circuits :)

About the solar pnnel thing what I did was to get a solar pannel and use it to charge up 4 AA batteries at 1.2v each then you connect phone to the batteries

That way you can leave charger in the sun withought your phone even connected then plug phone in to the batteries
It works 100% :)

regards,
Danny