I have 18650 batteries. My charger is a Nightcore Q2. Sometimes I put batteries in the charger for the day and forget (hey I'm 60) and they also sit overnight. The last time, they were in the charger for 24 hours. I'm sure it has some protection (reduces charging rate) but not sure it actually stops charging. It's a simple charger (no screen... just LED lights) so I can't check actual voltage. I also remember a video by Mooch saying it's better to only charge them to 80% (in fact, it also mentioned only letting them get down to 20%) Any thoughts on this?