Close up of battery in mower.Battery pack.
OwnerRyland
Owner's Other EV1979 Honda CX500
LocationMenomonie, Wisconsin United States map
Email email image
Vehicle YardMan Electric
Factory built as an electric push mower
that came with two lead gelbattery
packs that drop in to the battery well
so you can swap batteries when one gets
low, my update to this mower is adding
a lithium battery pack that has more
capacity then the two lead gel packs
put together.
MotorBriggs and Stratton Permanent Magnet DC
Stock motor that came with the mower from
the factory.
DrivetrainOperator pushing.
Controllerunknown
The controller on this mower is just a
lite duty contactor that also shorts the
motor for dynamic braking of the blade.
Batteries60, 3.30 Volt, Lithium Iron Phosphate
Battery pack is made up of the 60 cells
from 6 "36v" (really 33 volts) DeWalt
cordless tool battery packs with BMS
removed (because they burned out) each
group of 10 cells was left as a 33v
pack and all 6 of those were then wired
together to make a single large 515
watt hour battery pack that is much
better then the stock 24v 10 amp hour
lead gel batteries.
System Voltage33 Volts
ChargerDewalt DeWalt 36v cordless tool charger.
Stock DeWalt 36v cordless tool battery
charger with a charging cord coming off to
plug in to the mower.
HeaterSun shine.
InstrumentationDoc Wattson meter wired in to the
battery pack, I picked this meter
because it logs the lowest point in the
voltage sag along with peek amps, along
with telling me amps and watts that are
being drawn and the current battery
voltage.
Top Speed3 MPH ( 4 KPH)
It's a push mower.
Range2 Miles ( 3 Kilometers)
I can easily mow a standard city lot with
a blade that has not been recently
sharpened, mower set to lowest height and
still have power left over.
Watt Hours/Mile100 Wh/Mile
This is just all just a guess...
The mower draws around 250 watts while on
but not mowing and jumps up to 350 to 450
watts while mowing.
Seating CapacityNone
Curb Weight40 Pounds (18 Kilograms)
TiresHard plastic
Conversion Time2 hours to rip apart the DeWalt lithium
battery packs and build up the single
large pack.
Conversion Cost$800 for the lithium batteries, the
charger, mower, spare Anderson Connector,
wire and misc parts.
Much lighter then the stock mower with lead acid batteries,
lithium battery pack fits and plugs in to the stock plug on
the mower so the lead acid packs can still be used or the
lithium battery can be removed from the mower and installed
on any other device or vehicle that has a 50amp Anderson
Connector.
Everyone likes using this mower because it's supper easy to
use, as powerful as a gas mower and pretty quite, the only
draw back was with the lead gel packs as it took both packs
to get the whole lawn mowed, with the lithium pack I can mow
the whole lawn on a single charge.

code by jerry