Making a project that is battery operated is always a challenge because you need to overcome several obstacles as the placement and mounting of the battery, managing its voltage, and charging, as well as how the battery is electrically connected to the rest of the circuit.
In a previous project, I just simply used hot glue to mount the battery and its protection and charging circuit to the back side of the display frame and that worked, but it looks awful. Additionally, since I did not have any contacts to push on the battery terminals to make the electrical contact, I had to solder wires directly to the battery terminals which in the case of 18650 lithium cells is not recommended at all.
So motivated by this mess, I decided that I can do better and I've set to design a PCB that can solve all of these issues. The PCB has a battery holder so I don't have to solder directly to the battery and it also has positions for mounting a switch, mounting the power bank module to monitor the battery voltage, and to also handle the charging when needed.
Additionally, since these power bank modules require a certain current to stay on, the PCB has some pads where an additional load resistor can be added and it has multiple positions to solder the output wires from the 5V output of the power bank module. The PCB can be directly ordered from PCBWay and you can get 10 pieces for only $5.
You can watch the video below for all of the details of the PCB, the power bank modules, and how to assemble and use everything.
Tools and materials used in the video:
- Power bank PCB - https://www.pcbway.com/project/shareproject/Electronics_Project_Powerbank_55fa070c.html
- CB-18650-PC2 battery holder - https://s.click.aliexpress.com/e/_DdRH3cr
- Power bank module: https://s.click.aliexpress.com/e/_DBhJtvv
- 18650 battery cell - https://s.click.aliexpress.com/e/_DkKXHkP
- Soldering station - https://s.click.aliexpress.com/e/_DegRGVH
- Multimeter - https://s.click.aliexpress.com/e/_DBxGXqT
- USB Power Meter - https://s.click.aliexpress.com/e/_DDrl1Ll
- Wire snips - https://s.click.aliexpress.com/e/_DnB0wMb
- Resistors kit - https://s.click.aliexpress.com/e/_DELZuOJ
- RGB Flash LEDs - https://s.click.aliexpress.com/e/_DEtrn1h
- Soldering helping hand - https://s.click.aliexpress.com/e/_DFVA1Yn