I got the tools. I got the new batteries. Now wish me luck for replacing the batteries of my 20+ year old iPods. A classic gen 6 and a 3rd gen Nano.
The iPod nano 3G is open. And as expected, it has a bloated battery. But that can be fixed. It is still working, so a new battery should bring it back.
@jwildeboer Wow. Please tell us your experience how easy or hard it was. I have also a nano and a classic. Both need a battery replacement.
Where have you bought the needed stuff? And is there a good how to? Do you need soldering?
@thorsten The best how to is the iPod Repair clinic, a guy with 20 years of experience, sharing his wisdom. https://www.youtube.com/watch?v=5V-ZqzuxN8Q
How to replace the battery on an iPod Classic 6th & 7th Generation

YouTube
@thorsten Yes, you need to understand how these clips work that hold everything together. Because you need force to get them to open. The nano need soldering, the 6/7th gen doesn't.