Introduction: How to Make a Very Cheap 4500 MAh Power Bank
When I searched the stores for a power banks, the cheapest I could find was not always reliable so in this instructable I am going to show you how to make a very cheap power bank.
Supplies
1 x 18650 Li-ion battery.
(If you can find a laptop battery pack you can take a working battery from inside.)
1 x USB battery charger.
1x 5V USB booster
(If you can find a dead powerbank ,you can take the regulator circuit instead of the usb charger and the 5v booster. )
1x 18650 battery base
1x toggle switch.
Step 1: Assembly
I glued two circuits together at the back of the base of the battery. If you are using a power bank circuitry then you will have to figure out for yourself a way to glue them.
Step 2: The Wiring
I first wired the batteries to the battery charger's B+ and B- pins. Then I wired the Out - of the charger to the In- of the booster. I put the switch between Out + of the charger and In + of the booster.
I am using a USB booster because the voltage of the battery is 3.7 v and phone's charge at 5v. So I boost the voltage to 5v using the booster.
That's all you need to do to make the power bank. This is the video for this instructable
Step 3: Going Further
I could only add 1 battery as my charger can only handle 1. But if you can buy a battery charger that can handle more than one you can have more than 1 battery wired as parallel.
If you want you can add another USB booster to have two power outlets.
Thank you!