In built charging rules! :smiley:
Imagine taking out your cell phone battery and having to have the charger with you every time to charge it :weary:
This is also why we carry multiple lights, one on charge, one in use :wink:

Very rarely seen the smaller cells maintain 4.2v after a little rest out the charger except some HQ 18650’s, a little undercharging is good for the cells too.