Yup, exactly the case, except that no amount of charging revives the batteries; they're as good as dead most of the time. I just run my PB 1xxs with no battery at all except for one aftermarket one I have, just to make sure the dead battery won't leak and such.
There is nothing too special about the power adapters (the brick-shaped ones that should say "Macintosh PowerBook AC Adapter"; there are three variations, but the PB works well with all of them. Just don't get the one that says "Apple Low-Power AC Adapter" as that's for the PB 150 only.