I made this for my next project.
How to connect phones with 4 pins, take a look into comments.
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Step 1: "Battery"
I took pins from SD card adapter and glue them with Super Attak glue on piece of wood.
I used 82kΩ resistor.
Step 2: Power Supply
After couple of months I can say this is perfect power supply. It has enough power and it does not go hot! I bought it on Ebay for some bucks
Lithium Charger Step down 5A 5V-32V to 0.8V-30V Power Supply Module LED Drive 5A