A23 batteries are similar but smaller than AAA batteries but they release 12 volts.
I'm now talking with the seller to know more about how to power the module. He suggests using a 12V 7Amps but this is too heavy to lift it up 15 meters on a telescopic pole. Weight is important here since the telescopic pole bends and moves a lot if the spraying device is too heavy.
Need to keep thinking...