If the Voltaic battery is not charging from a wall or AC charger, please do the following:
1. If possible, try an alternative charging cable to test to see if the cable is faulty.
2. Confirm that the power is going into the Voltaic battery's Input. On the V88, this port is labeled "Input", on the V15, V50, and V75, the MicroUSB input is on the side of the battery.
3. Allow 10-15 minutes for the battery to recharge. If the battery is completely drained, it may take a few minutes before the battery builds up enough charge to start showing the LED charge indicators.