Our IMR 18650 Rechargeable 3.7v Batteries will run up to 12 hours. The unit does require both batteries because our gimbals require 7 volts to power on and each battery puts out 3.7 volts. You can not charge the gimbal through the handle. The batteries do need to be removed and placed into the charger. You can purchase a wall adapter for the micro USB and charge your batteries through wall outlets.