I bought a camera in China in 2009, even waterproof! After some time stored unused discovered, When I went to turn it on, the battery went into space.
Chinese Li-ion batteries generally swell and don't carry more. You should never leave a battery inside the device for a long time! It was really hard to pull out the battery after it swelled!
To replace the battery I bought this bloated below on Ebay:
It was hard to find the right battery, because many have the name NP-40 and are different.
On the left we have a bad battery and on the right the good. You can hardly see that is swollen, but it's enough to hold it inside the camera.
One more PIC!
I bought on Ebay, so I leave a link to a search for NP-40 in this shopping site. Watch to make sure the drums purchased is equal to that you have in your camera. I leave also link to search the Allchinese system that searches for products in several Chinese websites at the same time: