This may be because your battery is old. Before replacing it, try this trick. It may help! forum

Unfortunately, this could be a result of several issues. It could be a software conflict, a bad capacitor, or even a motherboard malfunction. Try this forum, hopefully you can find your answer there!

Your heatsink's radiator, also known as the fan, is probably dirty and is capable of cooling your computer. This forum may be able to give you additional information about hwy your device is over heating and how to fix it.