Wiring Diagram for Kobalt 837886 (Robotic Mower Project)


Feb 20, 2017
wait, so they are 35 ah? because i gussed they were 12ah and you said i was right. then you said they were 35ah.
okay besides that.
but yea you should have plenty of battery life to do your yard, are your batteries powering the blades to?
and with those 2 250 watt motors, you should be able to get over ANYTHING as long as you have grip,
when i built my electric scooter, i got a 500 watt 24 volt motor, a 36v 1000 watt speed controller, 3, 12ah, 12v batts,
totalling at 36 volts, giving the motor a 12v over volt,, putting out 750 watts in the motor, add that to a 80 tooth rear sprocket, i was doing 25 mph, and a but ton of torque, imm 13 and i have a lawn business and i have about 10 yards, so i would haul around my lawn care equipment in a mower trailer with ease, imagine seeing a kid going 20 mph on a scooter pulling 300lbs of lawn equipment down the road lol
Yeah sorry, I misread your post. They are 12VDC, 35AH AGM deep cycles x2. Series connected obviously. I have a 24V Battery Tender to charge from, but I also bought a 12V 15W solar panel with the intent of building a small garage/shed for the mower that it will pull into and charge itself from the panel on the roof. I'll use an Arduino and some code to alternate charging each 12 battery until both are at capacity, then trickle them. I need to design a mechanical switch that will separate the series bus under the mower when it drives into the shed. I've got a great hobby metal shop where I do all this stuff in my retirement. That will be fun I think.

The batteries aren't powering the mower blade because that's a 40V brushless motor with a Lithium pack. Originally the unit was going to be gas, but switched to this design for a few reasons. I actually had a linear actuator on it at one time that raised and lowered the deck height remotely for different grass lengths. But (sadly) the geometry sucked. It made the wheelbase so long the unit wouldn't be able to maneuver though my trees and bushes easily, so I had to scrap that mod. But it was fun to try at least.

I have some onboard Arduino circuits I am just putting the finishing touches on too. One is a tilt sensor safety switch, and the other uses a flex sensor in a piece of vinyl tube on the front of the mower. If it bends too much because it hits something...it shuts down the blade. From the two AGM batteries I also run both 5VDC and 12VDC Buck convertors to separate buses in case I want to add more features. Video is an option here obviously and I am looking around for the right wireless camera.

There is more detail on build on the Metal Working site I belong to if you are interested:

I'd LOVE to see some pics of your scooter. I think those things are so cool, and they look like fun to build. What did you use for your controller? I used a 2x60W Sabertooth for my build.
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logert gogert

Well-Known Member
Jan 11, 2020
36 Volt 1000 watts Brushed Motor Controller. 36v 1000w 36volts 1000watts
i didn't really use anything for the controller, just bought it, and wired it up, but it wasn't as easy as it sounds when i said, "and wire it up" but if you have anymore questions about it id be happy to awnser, i love talking about stuff i built lol,
but obviously you're MUCH more inclined than me, i could never, do what you did, if it was something like my scooter, yea, i could build it.
but i don't think i could built it out of pretty much nothing like you did XD