Battery overheating woes

Hello, Tom my Sony laptop is a 505 series I recently upgraded hard drive, memory etc... It is still smoking fast better than my centrino duo. And I didn't' have the money for a new Vaio but I want to continue using this as well. But it is as hot as the dickens and my battery is the one from when I go it and it only lasts for like 30 minutes when I have full lights and power my question is will it start and run w/out it in? I fear the heat of it will eventually burn everything out in my laptop will this work or should I even try at this point? verseofprose@gmail.com