Hey, thanks for the responses, guys.
Today, I took the battery back to the shop for an explanation, and the technician looked at the way the thing ran the drill backwards (I also brought the other, properly done battery as an OK reference), and hopefully it can be re-booted and also hopefully my second charger at home will be OK. The technician seemed mystified by the way the battery behaved. We shall see.
Normally, I would not be concerned, because I have two 18-volt Ryobi drills, plus three large and small AC powered drills, and really do not need my Ridgid drill, although I appreciate its lighter weight and smaller size at times. However, I do have a Ridgid, low-profile impact driver that uses those batteries and THAT item IS important, because I have used it when doing interior bracing with some cabinets I have built. (Tight fits inside, at times.) Pitching that tool would be a traumatic experience for me, and I am not even sure that Ridgid makes a newer version. I have seen some other brands that do the same thing (even saw one at Walmart of all places that has a dedicated lithium battery), and if push comes to shove I will get one of those. However, down the line the same problem will eventually repeat.
It seems weird that many of those hand tools seem well made and would probably last a LONG time if the batteries could be regularly replaced. It actually seems borderline criminal, because we end up filling up landfills with items that are actually mechanically OK.
It is too bad that companies do not offer powered hand tools that can be run by battery and can ALSO be run by a plug-in converter that uses AC wall power. That way, if the batteries can no longer be found you can at least use the tool the old-fashioned way.