A simple way to check

There is a simple way to check if it is electricity leak.

After driving, park the car, remove both terminals connecting to the battery. Thus your battery is isolated from the rest of the circuit, measure battery volts. Then leave the battery as is for over 16 hours, measure the volts again. If the battery volts does not change too much, that means your battery is good. There must be leak in the normal circuit. If the battery volts drops too much with the terminal removed, then your battery is bad.