Ryobi 18v lithium 4ah

[mxer]

I have a Ryobi 18v lawnmower that came with 1x 18v 4ah battery.

I would like to make another battery as one is not enough for my garden.

I have spare 6s multistar lipos as I run a 50v ebike.

My question is will my Ryobi lawnmower handle 25v (fully charged) ?

I don't really want to go down the route of 5s and new charges etc as I already bulk charge my ebike to 50v so would be an easy transition to 6s but unsure if my lawnmower would handle the extra 5v??

Anyone running a Ryobi 18v lawnmower on lipo?.

Many thanks in advance

 

[dogman dan]

I'd be inclined to go with 5s if you can't tell. If you can open up the mower and see inside the controller, it can handle 25v if the capacitors say 30v. But it's possible they used 20v caps. If you can't, cut a cell off a 6s, or just buy a cheap 5s. Charging, how you gonna charge 6s if you couldn't charge 5s? You will need some kind of RC charger. A cheap ass 50w one will be all you need.

I rather doubt there is a high voltage cutoff. It might be very simple in there, a brushed motor and no controller. That is how the older DC mowers are. If that is the case, then it can handle 6s fine. But don't go to 7s because too much will make the blade spin too fast. No need to throw a rock so hard it punches a hole in the wall of your house.

If it works, you'll never want to run the 18v battery anymore. 4v more is nice! I like to run my 6s (24v B&D) mower on 7s. I parallel up 20 ah of dying old lipos into my mower pack. Usually cells 3-4 years old. It might only dish up 5 ah actual, but 4 ah does my yard front and back.

Back to your setup, you can get pretty cheap knock off packs that fit Ryobi on ebay or amazon. I got one, which kind of sucks compared to the Ryobi one, but it does work. Or,,Christmas sales have started, buy a Ryobi tool and get another charger and battery. I'm looking at the little pole saw, to go along with my drills and skill saw. Last spring I bought the string trimmer, so now I have three batteries and two chargers.

 

[mxer]

Many thanks Dogman appreciated.

I'm guessing it's a brushed motor as the unit itself is very basic and light, I'm also guessing no controller either as I feel there would be no need (on/off) but saying that it does have a soft start?.

I'm going to give 6s ago and test/monitor. Wish me luch, I'll report my findings

Thanks again!!..

 

[dogman dan]

I'd take the cover off and look inside first myself.

 

[mxer]

Ok Dogman will do, be interested to see what's under there, so no harm having a look.
Have a great weekend, thanks.