My 1995 Volvo 850 died in stop & go traffic. All warning lights came on, radio faded. Jump started, then battery was weak. We charged the battery off and on for a couple of days, car ran OK but warning lights stayed on. Warning lights went out, but battery continued to be weak, and we continued to charge off and on for a couple more days. Then the battery exploded. We replaced the battery with a new one 2 days ago; today the battery is over-charged; registering over 16.5. Could this be an alternator problem, voltage regulator, or what?

 

Yes, yes, and possibly.

If you're not comfortable diagnosing auto charging systems then get it ckd out by someone who is. Most likely, at a minimum, you have a faulty voltage regulator, but that is just a guess based upon the info presented. The voltage regulator is a component on the alt; if you replace the alt, you'll automatically get a new voltage regulator too.