I'm using a 3.7V Li-ion/Li-Po battery with a TinyZero, IMU, and Bluetooth module. Everything runs perfectly when the board is connected to my computer, even if the battery is plugged in. But as soon as I unplug the USB cable, the system won't power on at all.

I've tried multiple fully charged batteries and ordered a few new ones just to be sure, but nothing changes.

Does anyone know what the actual power requirements might be or what could cause the TinyZero not to run from battery power alone? This setup should operate directly from a battery, right?