I have the same problem at the moment. I think it is either your chargers has stopped working or you will have to buy a new battery. I think my laptop battery is dead. I tried everything to revive it but it didn't work. Most likely you will need to be a new battery. If it isn't the battery just return it.
Well thats easy. To figure out if your problem is the battery or the charger think back if this problem occured over night or through a cuple of days. If over night it's the charger. Also if you haven't used your laptop for a while and let it be on a low battery, thats very bad for your battery. If you have a volt meter by any chance tell me, because then we can figure out the problem in no time. Hope this helps.
Are you using the original charger that came in the laptop? If you bought a third party charger, you might of bought one that outputs too many volts, which will kill the battery, and it can also mess around with the rest your computer as well if you use an incorrect charger long enough.