I did not know you could get a charger that would charge multiple batteries simultaneously. Did a fair bit of research when I learned it would be safer to use a charger that monitors/balances the cells while charging (as opposed to just using the charger that comes with the toy). I use term toy purposely, because his drone is inexpensive and is sold as a toy (UTO Quad-Copter, which was gifted to him by someone who really did not know anything about RC - and neither did I). However, after doing some research I do not regard these batteries as toys, so taking charging seriously. Anyway, we ended up getting a SKYRC iMAX B6AC V2 charger, which seemed like overkill because it cost more than half as much as the drone itself. Have been happy with it, but can only charge one battery at a time. Can you recommend a charger that can safely charge multiple batteries at the same time?