Portable Mobile Phone charger

[vick5821]

Hey there,

I plan to build one portable mobile phone charger. This is because my handphone always runs out of battery and when I need to use my handphone, the battery is empty. So I plan to build this to be used when in emergency case.

Can anyone suggest to me how to build one ?

Is it ok to just use the simple concept of Vin = 9V, Vout=5V from 7805 then use to charge my handphone ? I am using Nokia 5800 XM

Thank you

 

[BobK]

It would work, but it will require about 3 9V batteries (the small rectangular ones) to charge your phone once.

Bob

 

[CocaCola]

Yeah the 7805 should do it for many phones when charging using the USB port but many new phones want in excess of 1amp when charging without a feedback from a USB host, so you might have issues if it things it's hooked up to a 'charger' and draws excess current that it won't draw when hooked to a real USB port...

There are lipo devices designed for just this purpose and they can be had reasonable...

 

[donkey]

if I can help I have found there are already a heap of portable chargers for mobile phones. I know its not as fun as making your own. the iphone seems to have a heap of solar panel ones, there is the dynamo ones and then a simple battery pack that plugs into the phone charging part.

 

[vick5821]

I tried to build one as the existing one is very expensive..I just want to have a portable charger that is not necessary fully charged my hp.