IKEA Koppla chargers would be perfect for this. https://www.ifixit.com/Guide/IKEA+KOPPLA+Connector+(fix)/126573 https://www.ifixit.com/Guide/IKEA+KOPPLA+Connec

IKEA Koppla chargers would be perfect for this. https://www.ifixit.com/Guide/IKEA+KOPPLA+Connector+(fix)/126573 https://www.ifixit.com/Guide/IKEA+KOPPLA+Connector+(fix)/126... I expect you could even fit a Raspberry Pi Zero inside if you replaced the charger electronics with something smaller.