My Jagdpanther has a remote charging port built in, but I never use it as it's a very, very bad idea to charge batteries in the tank. If something goes wrong you not only lose the battery but the whole tank as well. That's why you can't find them stateside, they don't sell tanks with remote charging capabilities over here.

But, if you insist on doing this, bad idea that it is, the charging port on my JP is simply wired in parallel to the battery input.

Hope that helps.