Q: What do the four flashing lights on my ZMI battery pack mean?
A: All of our battery packs feature flashing LED lights in unison to indicate the battery level when you are charging a device. The actual number of lights participating in the flashing corresponds to the current battery level. If your battery pack is over 75.01% full, it would be normal to see four blinking lights.
The flashing of the LED lights is a designed feature for the purpose of saving battery and reduce heat. As energy-efficient as LEDs are, they do draw some power and generate some heat if left constantly on. By flashing them, the battery pack doesn't need to expend as much energy as it would if the lights stayed solid.