Solar/Battery Voltage Monitoring

I'm hoping to use a Konnected board as an all in one option in a detached garage where z-wave signal will be spotty at best, while WiFi connectivity will not be a problem. The detached garage will have a solar array with a standard (non-smart) charge controller that will maintain a 12v battery array. I plan to use the Konnected board for various sensors in the building and I'm wondering if I can also use any of the inputs to monitor the battery array's voltage.

I'm assuming if it is possible I'll need a buck converter of sorts, but I appreciate any input you have.