I created a new thread for you. Basically, all you need to do is figure out which forum you want to post in, then create your thread there using the "New Thread" button located at the top left of the forum. I put this in the General Electric Discussions for you.
As to your question, yes you can use that battery to charge with, depending on how big your packs are (if 3 cell packs, you should be just fine). When I first started, I bought a deep cycle marine battery to take to the field with me. But now I just use my car battery.