How long does it take to charge a battery up notsure.gif . I have one for my Vectra but it was flat so I put a battery charger on it. It's been on for hours now dunno.. . The battery charger has a green light on it for when it's charged but it's not on green yet. I even went outside just now to try it on the car and it's working, my car has life again. Should I just let it charge up?