There is no difference between "although" and "albeit". Not the merest shade. "Albeit" is an outmoded word which always marks the user out as a pretentious clown. The decline of "albeit" was a natural process (which appears to have gone into reverse, lamentably, thanks to the efforts of the meretriciously-trendy chattering classes), hardly surprising when you consider that its presumed origin, "although it be", is not only somewhat awkward and ungrammatical in itself but also has the words giving rise to its bastard offspring in the wrong order. On top of that, it sounds awkward and it certainly looks awkward in print, almost demanding an unnecessary split-second's mental processing. "Although" is a lovely, elegant word, correctly used. Innit.