dh@. wrote:

Someone told me it's possible to charge an inverter
system's batteries using a battery charger plugged
into the inverter that's being run by the batteries
you want to charge. Is there any truth to that, and
if so, how does it work?

It works very well, but how to do it is a secret. Don't listen to those
who say differently, they are ignorant of new scientific breakthroughs.

Send me five hundred dollars in cash and I'll send you the instructions.

You won't be sorry you sent me that money, I promise!