Unfortunately I think you are probably correct. Batteries, even the rechargable ones reach a point(after enough cycling) where they simply need to be replaced. The charger and outlet are probably still in perfect shape, unfortunately this is probably just due to the age of the battery.
We actually see this a lot with car batteries, that even though they are recharged regularly through driving they simply die after a while, same thing with laptop batteries, cell phone batteries and even self powered lights. Though I can tell you 12 years is a great
amount of time to get out the DustBuster. I had one for a long time myself.
The replacement batteries are actually pretty hard to come by, and when you do, they can get expensive(sometimes 20 to 40 dollars) - they do offer a non-rechargable skeleton to put in the back I believe but regular use of the vac will make this very expensive. One of your other options is to call your local vacuum store and see if they can source anything from any of their private manufacturers or suppliers for you. They may be able to fabricate a battery if you still want to use it. This is worth a try.
I actually took a few minutes to source some choices for you from walmart. If you click here
you will find a selection of various vacuums in different price ranges, all rechargable BUT with the added benefits for some of them being WET and DRY vacuums. I know my little dust buster was dry only, so this is definitely something to consider.
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