Home built cell phone power bank

Simple 12 – 7v cell phone charging circuit for your home built power bank.

Connect two 3.7v Li-ion batteries in parallel, then follow the above circuit to regulate the voltage to the phone required voltage.

The led in the diagram is used to represent the phone plug.


Read: Trump says he wants a solar border wall — here's how many homes it could power

Part list

1. Lm317T voltage regulator
2. 75k resistor
3. Phone plug or USB plug

Powered by JF Green Energy Concept