Hi. Unfortunately, this device does not have an indicator or lamp indicating that the battery is being charged or not. But you can only be sure that the charge is present if you open the device and put an ammeter in series with the battery. If the main electricity (AC) is present and the battery is being charged, the current measuring device will measure the current and its direction. If the main electricity (AC) is cut off and the device starts working on the battery, the direction of the current will reverse. The direction of the current that is read from the ammeter will tell you whether the battery will charge or not.
