Battery pack from Old Laptop battery.

This week I made this power bank to charge my mobile on the go. It has Li-ion batteries and packs 4200milliamps of power. It charges are types of mobile and provides a constant 5V power. The maximum current output is about 600mA.

The case is 3D printed to be compact and sleek in your hand.
https://www.youtube.com/watch?v=ZZrsI1alguo
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PARTS REQUIRED:
- 2 Li-ion batteries: http://goo.gl/OBrGIE
- TP4056: http://goo.gl/yF0i3F
- 5V step up booster: http