I have a black &
Batteries are only good for about a year, if they are older than that, take them back to the store and see if they are guaranteed at all, (all Ryobi tools and batteries have a date code on them, and they are all guaranteed for 2 years, a little plug for Ryobi,) that is all I buy now days, they work great. So, to check your charger, you will need a volt meter set on 12 or 20 v dc, and see if the charger is putting out, if not, then, the cost of a new ryobi might be the same as the fix for the black and decker. That is if you use the thing, we use our cordless tools every day and charge them every night, hope this helps.