I’ve read a bunch of opinions about the batteries, but what I’ve gathered is;
Mini batteries are not LiPos as in previous Mavic batteries, and all of the LiPos I own for my model airplanes. LiPos are sensitive to storage voltage, and should be stored around 50% State of Charge.
Mini batteries are LiOn, similar to the batteries in your cordless tools. This battery chemistry is much less volatile, and more tolerant of staying fully charged for extended periods.
I charge the batteries after flying and leave them in the charger bank until I fly again.
That’s the way I understand it, but if I’m wrong I’m sure someone will chime in.