My 3Gs already expired long ago...
the symptom of the issue is not jz battery deterioration...
if u hav some extensive app running (say: GPS, FB, Game)
it could suddenly goes off in sudden, n would be difficult to start again...
it will turn on...then u ll see the logo loading...then its either off again...
or it will get into home screen if u lucky enof after few tries...

if it can't start...i need to get a cable to connect it to power up...(i call it jump-start phone =.=")

should i send back to maxis for refurbish unit?
i do intend to repair it then use it for 2nd phone or my family if they want it...