24v panel with 12v battery

Welcome to the forum Tordfish,

Assuming this is your controller,

https://www.wattuneed.com/en/mppt-regulator/1525-epever-mppt-tracer-1210a-10a-0712971129153.html

As long as your Vmp-array is greater than ~24 volts and is less than ~66 Volts (Vmp-array-std for most climates), you should have no problem.

An MPPT type charge controller takes the high voltage / low current from the array and efficiently down converts it to the low voltage / high current for the battery bank. They are designed for this--Take any (within specification) solar panel input voltage and match it to your battery bank's charging voltage/current.

You have to be a bit careful, there are a lot of very cheap charge controllers that say "MPPT" on the label, but are actually PWM controllers (Maximum Power Point Tracking vs Pulse Width Modulation)  MPPT controllers are more expensive to construct because they have a good size "inductor" (copper winding around a core) which is not cheap.

-Bill