They do look like those, but that's not it.

These are Lithium Ion chemistry and are 6000mah square cells.

I've cycled it twice so far, neither time was completely charged either.

Each time, runtime was over an hour, cutting some fair sized stuff too.

I'm on my sixth year with a sears cordless. It used 2 12v lead acids in series for 24v but they only lasted 2 yrs. I then started using a zippy 6s pack which gives it close to original rpms plus a lot lighter. For normal yard edging it's great but if the grass is a little taller and dense it does get bogged down. Would be nice if they gave output rpms for these cordless trimmers.