B & D's quality isn't what it used to be. I bought this on 5/18/2018, and it never reaches a full charge. Used to be, when the light went off, it was fully charged. Not any more! The charge light NEVER goes off. I bought a previous battery on 8/2/2017, and it no longer reaches a full charge. This is much, much less use, compared to previous batteries I've had from B & D. Time to find another brand. B & D, if you're reading this: you killed the goose that laid the golden egg, and there is no excuse for such crappy quality. This a.m., I was using a recently-charged battery, and the power lessened noticeably. I could not believe it didn't even last for 5 or 10 minutes, so I got my other battery that was also charged for several hours, more than overnight. It didn't have the "zip" it normally had when fully charged.

This battery works perfectly in our Black & Decker Groundhog weed trimmer. It easily has twice the capacity and staying power of the previous, original batteries. I was able to do part of my yard with it just a few days out of the shipping package. It's ready to go after just an overnight charge. After spending several years dealing with a pair of weak and inefficient batteries, I was almost convinced that the whole product was poorly conceived and a waste of money. But this new battery has brought some joy back into working in my yard. At least for this task.

Worked for only a short time - several months - most aggravating issue was the 9-hour charge period with a very short runtime at full power (used to power a small leaf blower) followed by a loooong period of about half power, then sudden death for the battery after 17 minutes. 18-volt Lithium battery does not appear to be a mature technology for Black and Decker - go for the 40-volt fast charge system instead.
NOTE - Black and Decker has possibly the worse web support site ever - live chat does not work, email support page appears without text input fields, and no way to send - button hidden with bad html code. Could have been written in some basement in a weekend perhaps. Chat does not work, phone support has a hold time of over an hour - but the piano music and recorded hold voice are nice.
Bottom line - don't waste your dollars on this technology. And if one is so unfortunate to have more than one failed battery, standard protocol with B&D is to require the product be taken to a Factory Center for warranty analysis - a 50-mile round trip for us. Unacceptable IMHO.

Got this battery a few days ago, charged it fully and then tried using it in my grass trimmer. Lasted about 15 minutes before power dropped down to an ineffective level. The battery is the correct model and voltage for my trimmer but isn't worth the price since brand new it can't even run the trimmer long enough to get all the way around my lawn. Am returning and getting a corded trimmer instead. Tired of recharging batteries; I'd rather deal with the cord.

Obviously, Black & Decker is a fantastic name and brand, and I own four different battery powered garden tools that are an excellent workhorse every weekend, but only as long as the batteries are operational. Its become pretty clear that in the past couple of years, B&D has cheapened the components of these 18v batteries. I know this for fact because the original black battery that came with my devices still charges and works for a decent amount of time, while the newer black and orange batteries do not even last a year before they only recharge to about 20% of their original life. Last summer, on this site, I purchased the double set and wrote the date 7-10-16 on each of them. A couple of weeks ago, I had to give up on those two because they barely power any of my devices for more than thirty seconds after getting a full charge. But have no fear, the original black ones still get the job done. Go figure. I'll try to reach out to B&D and see if they'll replace them. If not, I'm just going to reorder again on this site and be forced to live with the changing world we live in.