While charging my drone batteries I notice LED lights on only 1 battery. Do I have a bad battery or is there something wrong with my charger? This should be normal behavior.
According to the manufacturers specifications, the Phantom 4 Battery Charging Hub can charge up to three Intelligent Flight Batteries which will be charged in sequence, not simultaneously, according to their power levels, from high to low. It will take approximately 3.5 hours to fully charge three Intelligent Flight Batteries.
The DJI Battery Charging Hub is capable of charging a mix of Phantom 4 (4750 mAH) batteries together with Phantom 4 Pro (4850 mAH) high capacity batteries.