In this tutorial i am going to show you how to make portable usb cellphone charger V2
Its very simple and it will cost you only 2$
So parts list
12v car usb charger (smaller the better)
9v battery connector
Tools you will need.
Hot glue gun
If you have any question be sure to ask them in comments ;)
You can make this even more cheap if you use rechargable 9v battery.
Hope you enjoy!