Well this is the bottle battery pack from Luna Cycles, using Panasonic 18650 cells, and I'll be charging with their "smart" charger which allows me to choose the charge rate from 1-5 amps, as well as the charge percentage from 80% to 100%. I should hope that it will be safe. I read someone say they never charge their e-bike battery unattended or while sleeping, so I'll see how it goes for a few hours while I'm at home and awake, to monitor things.