Putting the old guy next door "on steroids".

LockH

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Ummm.. Started out in Victoria BC Canada, then sta
OK. NOT the theologian (I refer to him as "Padre"... hehe) but his LAWNMOWER.

... Watt is a Yardwerks bettery-electric "24V, 20Ah, 240 W"... instruction manual here:
https://www.manualslib.com/manual/820725/Yardworks-060-1753-8.html

... so a sealed Lead acid battery [cough cough]

My mission. To STUFF his battery compartment with lithium. (Meaning the mower...)

From their manual "USE ONLY A YARDWORKS REPLACEMENT BATTERY (060-2110-2)" [More coughing here.]

Ya can still buy these... things from a local Crappy Tire:
http://www.canadiantire.ca/en/pdp/lawn-mower-battery-for-60-1753-24v-0602110p.html

MY thought... given that "weight not a concern" is to just go with LiFePO4 cells.

Currently (Ebiker joke) can shop local:
https://www.goldenmotor.ca/products/12AH-LiFePO4-Cell.html

... for "just" 12Ah cells ("Buy in bulk and save!") watt I suspect is STILL "better" than a "20Ah"-rated lead battery. (Found on Wiki: "the gravimetric energy density of LiFePO4 battery is 130Wh/kg, four times higher than that of Lead-acid battery, 35Wh/kg".)

Think so, maybe? Suspect the Li will be slightly less "ambient temps" sensitive also. Lessee... One LiFePO4 cell "3.2V as its nominal voltage during discharge". So. Say 8 cells wired up in series. Right now "CAD 54.00"... at eight cells $432 Cdn. Round to say $500 (including Canada and Ontario "HST").

Sound like a plan? LiFePO4 cells with a cycle life of >2,000 (assuming full discharges each time...)

Watt am I missing? (Remember you LiPO fans, object here is for pack to be "bullet-proof". ;) )
 
This might be a good app for some 10 amp hour Headway cells.
I use a 5 amp hour 18s li co pack and at most use 2.5 amp hours mowing the yard.
The yard is 60 foot by 100 foot. About half of the yard is grass or weeds that get mowed.
 
Just build a pack from these. You will only need 32 from the box of 80. :p I have bought 6 boxes and of the ones checked so far, they all seem to be around 3.33 volts. Use the best offer and offer $80, they will reply with their $100 minimum. :wink: You may need to have them shipped to a US address and retrieve them somehow. :roll:
 
Whatever you use may need to be able to handle a significant startup current spike, especially if it's started while on top of some grass.

To find out how much of a spike, and for how long, you'd need to measure the current during a startup--a wattmeter would be the best way.

SLA can handle quite an initial spike, even if it doesn't do well sustaining that over time.


(I suspect the "240w" is the power it takes to just sit there spinning the blade in the air, not what it takes while mowing).


The manual linked in the OP says:

24 V, 10 Ah Lead acid
Run time......................................................................................................approx. 50 - 60 minutes
Since it's only really going to get about 5-6Ah out of that SLA, then that's about 5-6A (if it lasts for an hour). At 24v nominal that's only about 120w, which sounds too low.
 
Electroddy said:
Just build a pack from these. You will only need 32 from the box of 80. :p I have bought 6 boxes and of the ones checked so far, they all seem to be around 3.33 volts. Use the best offer and offer $80, they will reply with their $100 minimum. :wink: You may need to have them shipped to a US address and retrieve them somehow. :roll:

Interesting... but we're in the Great White North (Canada, eh?)

Item location: Leander, Texas, United States
Shipping to: United States


This item does not ship to Canada

:wink:
 
LockH said:
Electroddy said:
Just build a pack from these. You will only need 32 from the box of 80. :p I have bought 6 boxes and of the ones checked so far, they all seem to be around 3.33 volts. Use the best offer and offer $80, they will reply with their $100 minimum. :wink: You may need to have them shipped to a US address and retrieve them somehow. :roll:

Interesting... but we're in the Great White North (Canada, eh?)

Item location: Leander, Texas, United States
Shipping to: United States


This item does not ship to Canada

:wink:
I did include the caveat in bold, :D Surely there is someone near the Border where you are, that would cross ship to you.
 
Hehe... ES user Troy in Buffalo... I know he likes to travel by this way sometimes. :) Yah caught his Maxwell EPO bike?:
https://endless-sphere.com/forums/viewtopic.php?f=3&t=70440

(When I remember, always apologize for pooping in his drinking water...)

... but re watt flavour of Li cells to get... much prefer to source locally... support local biz. (`Course, anywhere in North America is "local" these days. :wink: )
 
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