Overview: The battery replacement process for the iPhone 3G easier than the 2G. It involves removing the touch screen glass, then system board at which time you will have access to the battery bay. It's really difficult to damage your iPhone during the process because of Apple's better hardware build on this model. Don't damage, crush or puncture the existing battery to limit the risk of fire. Follow the video and you'll be successful in the battery replacement process.
For additional battery replacement details, check out our battery replacement BLOG!