Adding a Battery and charging module
I have used a 3.7V Li-Ion 700mAh Battery, a TP4056 Charging module with protection IC, a CKCS BS01 step-up module and a micro slide switch that is shown in the charging circuit image.
It has 2 resistors (A and B) on the front side. Remove both of them to set the output to 5V. You can use a soldering iron to do so.
