I tested the battery in another TELLO and it works. But my TELLO does´nt detect the battery charge. I guess the central card is damaged, or someone knows some solution?
have you tried with a 2 Ampere charger and a good quality cable? remember that cables are not all the same.
if the problem persists with multiple batteries, it is likely that something is wrong with the card or simply broken the mico usb connector.