These are shit. Aging wheels on YouTube did a review on them.
They have lead acid batteries, so it’ll trim a full yard once or twice on a charge for about 6 months. After a year or so you have to replace the batteries. That’s like 400 bucks worth of batteries every year.
I believe this is the same model the Aging Wheels guy on youtube bought, and then the inevitable happened. You could desulfate the batteries, but he stuffed it full of custom lithium cell battery packs instead.
You are correct that using lead-acid in this application is a really bad choice. Even deep cycle batteries will have a crap energy-to-weight ratio. This was the result of the manufacturer (or more likely Home Depot themselves, who specified the product) to rush something, anything out the door to jump on the bandwagon as fast as possible. You see this shit coming out of China all the time, like the little "neighborhood electric vehicles" that in their stock trim leave the factory with like two lead-acid golf cart batteries in the back that give it a range of approximately eleven feet.
I was at Home Depot trying to get a gas powered hedge trimmer. I have almost an acre of property, and there are tons and tons of bushes around the house.
Salesman says I should buy electric. I tell him yes, but I'd have to buy another battery or two just so I can do all the work in one day. Which makes it significantly more expensive than gas.
"Ah that's the thing. You just replace everything with electric, and you get a battery with each device!"
Okay, so, what if I want to cut the grass, do the edging, and trim the hedges in one day? I understand the need to switch to electric and reduce emissions. But the number of towns banning gas powered lawn care equipment is just ignoring the obvious. Electric is simply not practical for anyone with a remotely large property.
The secret is not to buy your battery packs from Home Depot. The markup on those "genuine" Ryobi packs is insane, especially given they're just stuffed full of the same low quality 18650 cells as all the other Chinese garbage anyway.
I have a small fleet of Ryobi cordless stuff by now: A mower, a string trimmer, a blower, and one of those inflator thingies. I just buy the knockoff battery packs online for 1/3-1/4 of the cost and so far I've found the knockoffs to have just as much or more capacity and to be more reliable than the Ryobi branded ones. Home Depot wants $189 for a 40v, 4.0Ah pack. Or you can buy a "6.0Ah" knockoff which is probably actually still 4.0 online for $57. The price gulf on the 18v packs is even greater.