Battery Voltage Monitoring

Hello,

I have my project running on a Arduino Pro Mini 5v/16Mhz. I have a Lithium Battery connected to a TP4056 charge module and then the output of this is going through an MT3608 DC-DC step up converter to get the 5V to power the project. The project works and runs perfectly from the battery.

What I would like to do is ready the battery voltage so I know when it is ready to be charged. As the Arduino Pro mini is 5v will it be feasible to connect the outputs of the battery (nominal full charge of 4.2V) to the analogue pins to read the voltage without using any other components e.g. voltage divider?

Any help would be appreciated.

Kindest Regards,

Brett Rogers

BrettRogersUK:
As the Arduino Pro mini is 5v will it be feasible to connect the outputs of the battery (nominal full charge of 4.2V) to the analogue pins to read the voltage without using any other components e.g. voltage divider?

As long as the battery GND is connected through to the Arduino GND that will work fine. On my MT3608 modules the input and output GNDs are connected.

...R

Robin2:
As long as the battery GND is connected through to the Arduino GND that will work fine. On my MT3608 modules the input and output GNDs are connected.

...R

Very important: "As long as...."

OP should check up the charge-/step up- converter properly. I don't know whether galvanicaly separated devices exist. As Ronin2 says, it sounds okey.

It's a fully understandable and good project soo, good luck.