I have written an article in the past, but I am likely to write new articles in the coming days, anyway this one might been interesting for you, take a look to read about these energizers that would meet your requirement. https://dripworld.com/120-top-8-solar-power-generators/
I think you already got solution for your farm if not I am giving some solution. In India almost energizer chips comes from China and fixed them in metal bodies by Indians.
Try to get a best battery from a reputable company that will lasts longer.
Get best solar panels, wire, and their fittings from Indians since this also boost your fencing with good quality.