3G only works when plugged in!!!

[VegaPro]

OK guys i need help. I got my brothers 3G and to be honest it has had its fair share of use. The screen is cracked and has minor scratches. I have fixed iphones before but never came across this problem before. The iphone (only when plugged into the wall) displays the apple logo and then shuts off. So i try to hold down the wake/sleep button and the home button at the same time and then the connect to itunes pic shows up. That all fine and dandy but my phone totally dies after i unplug it from the wall. It does not work when plugged into my comp. Do I need a new battery or something?

[Broomhead]

Sounds like you need a new battery

[VegaPro]

Thanks, Thats what i figured. Whats the price range for a battery. I have a friend thats willing to give me his iphone for parts but just incase i need to buy one it might help to see how much one might cost.

[Broomhead]

I think they're around $70. I'll check and report back

search the internet, I found some for under $10