Not provide a dissertation on y 12 volt adapter battery charging is useful. My first attempt was charging the battery using 150 watt inverter that one didn't work. Next attempt was using a 300 watt inverter that also failed. Suspect the sine wave Distortion in the output is too great to support the bat rad battery charger I have a 300 watt pure sine wave inverter on order and let you know how it works. By the way this can be useful for people that have simple RVs and want to charge their battery and are too lazy to rewire their camper for some other kind of inverter if somebody already found an inverter that works with a 12-volt adapter already let me know what you ordered