What type of battery does the Treo 600 have, and is it removable?
Treo uses a rechargeable lithium ion battery. This technology provides long talk and standby times with very fast charging times. And unlike some older technology batteries, lithium ion batteries don't need to be fully drained between charging cycles. So it's really convenient—just "top off" whenever you have a chance.
The battery is integrated into the device and therefore not removable. You can purchase an add-on battery pack to help extend your battery life.