Is not charging - no red light

Yes, it can be replaced. Can be ordered from Black & Decker. Some people would say it's worth fixing others would not. Don't know cost of battery -- probably under $20.

Even if it can be replaced, I found that a dead battery sometimes damages the power plug / charger / adapter plug attached to the base. You can check this with a simple AC meter. If you don't read about 15VAC across the two metal tabs on the base, the adapter is either weak or dead. This means that even if you were to replace the battery, it's not going to be charged properly. In that case, the power plug simply needs to be replaced with a 15VAC adapter that can supply at least 130mA (original should have the voltage and amperage requirements embossed on it). Note that it just needs to be an AC (not DC) adapter in the general ballpark of 15 to 16 VAC (i.e. this is not picky digital electronics!). My various charger bases (I had 3) seem to use several slightly different adapter ratings, all for the same CHV9600. Cut off the old adapter, splice the wires to the new one (doesn't matter which wire is which, since it's AC) [preferably solder the connections, but a good inch or so of twisted wire will also work for a long time -- maybe use a small wire nut in that case] and cover with electrical tape. The power plug may get slightly warm (especially when charging a very discharged unit), but it should not get hot -- if it does, I'd just replace the dustbuster and charger.