I have Sony Vaio laptop and the problem with battery which is not charging. I can leve it to charge for hours and it will say 100 full when I start Windows, but after few minutes it will fall to 5 and laptop will turn it off. I hope you will be able to tell me what to do.
Your battery is obviously malfunctioning. You should replace it as soon as possible especially if we take in account problems that Sony had with batteries lately. I think that you are lucky if this is the only problem that battery caused. If you have warranty then everything is fine, just return them battery to receive new one.