So 1 year ago I got a iPod touch 6 gen and I loved it but the battery life is only lasting for about 15 minutes and I look after my I pod very well I never use it in charge I have a decent case on it.... so what more?
iPod, iOS 12
See this Apple article: Batteries - Maximizing Performance - Apple and this one About the battery usage on your iPhone, iPad, and iPod touch - Apple Support.
In particular, make sure you do not have the screen brightness higher than necessary and that the Auto-Lock feature kicks in as soon as possible. There's no point in having the display on long after you've stopped looking at the screen.
iPod 6 battery life
