Well, it is electric....

[Drunkskunk]

I got mad at my broken lawnmower for the last time this year. I spent all last summer repairing it over and over again, for diffrent problems. it started falling apart 1 month out of warenty, and it was a top of the line Troybuilt with a Briggs motor. The last briggs mower I owned had been in thwe family half my life, and it had replaced one made in the 70s. This last mower wasn't a lemon, it was junk by design.

I wanted something I could rely on. Something that would start every time, mow my lawn, and not give me any trouble for the next 10 to 20 years. After 3 weeks of research online, I came to 2 conclusions. No gas mower made today will do that. Gas mowers are Eco nightmares. Depending on which sorce you find, a mower is chucking out anywhere from 2 to 40 times more polution than a car.
the most creditable sources seem to indicate that I'll dump more polution from my mower than from my car this year, and I drive a gas hog of an SUV.

So I decided to give up on gas and go electric. Cords suck, so I went rechargable, and now have a 5 horsepower black &decker electric mower for all my lawn needs (and future Ebike parts)

Its 24V, 5 horsepower motor, with an unknown sized SLA battery, and after just a week, i'm already woundering what it would be like to mow at 36V?

I've had to resist taking a wrench to this thing to get a look at the motor. That much power is just begging to get bolted to a bike frame.

 

[Toorbough ULL-Zeveigh]

Joe average consumer who bought the B&D battery mowers naturally bled them until dry b4 recharging & parked it unplugged over the winter.
By next season, two at the most the AGM's would be sulfated beyond hope.
The batteries also seemed to me kinda undersize for the task & not the greatest quality.
Retrofit with A123 as soon as these go ded which probably won't be long.

 

[TylerDurden]

I own the CMM1000 24V. It's more mower than I need these days. It's also the second or third cordless I've owned. (I've given some away when I got a tractor )

They are great for small yards and grass that is not too dense. I would not expect to cut more than 1/4 acre with a cordless.

 

[Link]

Well, as an ex-owner of one of those things, I can attest that the 5hp thing is bullcrap. It's got a 40A breaker in it (I ripped it apart when I was getting rid of it). The breaker MAY have a delay to keep it from tripping when you first turn it on, though. I didn't take that apart.

Although, I don't doubt for a second that motor couldn't handle 5hp. It's a monster. Weighs like 30lbs. It spins pretty fast (I haven't checked the exact speed with my tach yet), so it would be a good idea to rewind it if you ever use it for anything else :wink:.

And yeah, the batteries in mine (I got it for used for free) were junk. The people I got it from got rid of it because "the batteries wouldn't hold a charge" anymore. However, after dissecting it, I could easily see that something had shorted the batteries across the traces on the charger's PCB. After I soldered a bit of wire to close the circuit, it worked okay. The batteries were severely damaged after this very, VERY deep discharge, so I got new ones. Worked much better.

Retrofit with A123 as soon as these go ded which probably won't be long.

:lol:

Awesome. You're going to need at least four packs to approximately match what's in there now. The 2 SLAs are 18Ah.

 

[Dr. Shock]

I have one of these with dead batteries. I liked it pretty well in its salad days. I might try it on a set of DeWalts. You'd think they'd be doing this themselves since DeWalt and B&D are the same company.

 

[Link]

You'd think they'd be doing this themselves since DeWalt and B&D are the same company.

Simple: Price. The mower is $300 to start with (I'm subtracting $100 for the batts). Adding $400 worth of lithium (which basically does nothing) doesn't really make sense. No one is going to want to buy a $700 mower that will only cut a quarter acre of grass just because it has high-tech batteries, even if they do last a long time.

 

[Dr. Shock]

Yes, when you put it that way... In fact the price on these things is high to start with compared to tried-and-true gas mowers. But they are much more pleasant to mow with when they are in good charge. Very quiet, no need to fool with gas and oil, and no cord.

 

[Link]

Yes, when you put it that way... In fact the price on these things is high to start with compared to tried-and-true gas mowers. But they are much more pleasant to mow with when they are in good charge. Very quiet, no need to fool with gas and oil, and no cord.

+1 on all points. Especially the price. If you take one apart, you'll see exactly how simple it is. A motor, batteries, switch, and charger are all that's in there. Oh, yeah, and a block of styrofoam.

 

[Ypedal]

Yeah.. i got me a Toro brand 4 stroke tecumeh self-propelled variable pace .. starts in 2 pulls or less every time.. or i take it back to HomeDepot.. 5 years !( 2 down.. 3 years to go )

I considered electric, but i have a fair sized lot.. takes 45 minutes if i walk fast.. I considered a home built e-mower that would use my lithium packs at 36v.. but no time for that now.. plus i got a free ride-on last year ! so the pusher will last even longer now ! hehe

 

[TylerDurden]

Yes, when you put it that way... In fact the price on these things is high to start with compared to tried-and-true gas mowers. But they are much more pleasant to mow with when they are in good charge. Very quiet, no need to fool with gas and oil, and no cord.

+1 on all points. Especially the price. If you take one apart, you'll see exactly how simple it is. A motor, batteries, switch, and charger are all that's in there. Oh, yeah, and a block of styrofoam.

Keeping the blades very sharp makes a big difference with the cordless... drag, & all that jazz.

:?

 

[knightmb]

I had a 6.5 self propelled Toro mower, which worked fine. I bought a Homelite electric mower and used a simple 1500W inverter to convert 12 volts to the 110 volts AC that the mower needed and basically had a cordless electric. It takes about 1 hour to cut my yard, so the electric mower can do it in one charge. The picture is a bit old now because I don't use (2) 12V 12AH batteries now, I use a single 12V 33AH battery (AGM). The irony is, the electric mower, even with that big AGM battery is still half as heavy as my Toro Gas mower was. So even though the electric wasn't self-propelled, it was light enough to push around with one hand, so the weight was really no longer a problem. In fact, it's so light that when I use the mulching bag, it can get so full of grass clippings as to cause the mower to tip over backwards, LOL. I know when to empty it at least.

The electric mower always starts at the flip of the switch, makes about as much noise as a dust buster and I can easily tip the mower on it's side to clean the blades. Unlike my gas mower, it would spill gas and crap everywhere if it wasn't sitting straight up. The gas mower (as with all of them) always has the problem of hitting grass that is too tall or thick and killing the motor. On the electric mower (which is only 1200 watts, barely 1.5HP), I have yet to encounter grass high enough or thick enough to stall the motor out. Actually, when it gets THAT much grass, it starts to jerk the mower around because the motor seems as though it's invincible from stopping. So I know then to cut the 1 M high grass a little slower and scrap out the tons of wet grass clogging up the blades.

I sold the 6.5 HP Toro mower long ago. It was cheaper to put the electric mower together than it was to buy the gas mower. So I recovered about $100 from the sale of the gas mower and kept the electric mower. The electric mower is still going strong and I always get the usual stares from the neighbors when I'm pushing around my electric mower with one hand while talking on the phone because it's quiet enough to talk to them. 8)

It's also fun to stop the mower, pick up a stick or something, pull the switch and be off again cutting grass without missing a beat.

[googlevid]-1609440962051898515[/googlevid]

 

[pwbset]

Expanding my garden into my back yard this summer and want to go electric mower so I'm not spitting gas all over my veggie boxes. Thinking of this mower from Home Depot (which I think is the same as the video above): http://is.gd/tIsD

So what's to keep me from powering it with a 24v LiMn pack made of spare konions? Figure like a 7s and maybe 20p aught to be a nice amount of cutting for only ~15lbs of weight eh? Thoughts?

 

[TylerDurden]

Check CL for used mowers with dead batts... I got one pretty cheap. (Maybe Shock still has his to sell ya.)

 

[gogo]

I used an elecric mower back in the middle 70's and I ran over the cord a few times (I had swimming to do). :wink:

I used a reel mower for two years until the stub axle came loose. I liked the quality of the cut, but you couldn't mow stuff that was double height.

Last year I saw my neighbor using this "flip-handle" electric:

It alleviates much of the cord hassle by allowing the cord to stay on mowed lawn between you and the starting point. You just flip the handle at the end of each pass.

After I got one my neighbor's started running poorly so he bought a different brand and said he missed the flip-handle. He gave me his old one and I fixed it by freeing up a brush wire and then gave it back to him. I got some Christmas cookies from them this year.

I've cut 12" overgrowth without bogging the 13A motor excessively. I also put a dethatching blade on it last fall and it worked great. People write reviews saying its underpowered but they probably didn't have a large gauge cord. I wouldn't use any other mower now just because of the ease of use the flip handle provides.

Id like to try using a 1500W 24V inverter with Milwaukee V28 batteries.

 

[PaulM]

Here's my cordless electric lawnmower. It is a prototype that a former employer was working to develop several years ago. I managed to get my hands on two of the old prototypes. I have just added the pieces of wood to try using some old NiMH batteries that I got from Rick K. It is meant to hold 18 or 20 AH AGMs by the rear wheels. The motor is a brushless outrunner (obviously enclosed) with built in controller, runs on 24V, draws about 30 to 40 amps for average grass. The deck is entirely aluminum: lightweight, corrosion resistant, and helps sink heat away from the motor.

I love cutting grass with it; quiet enough to listen to my MP3 player while cutting, no gas, no oil, always starts, easy to clean, etc, etc, etc. It will be a big disappointment if I ever have to go back to gas!!!View attachment DSC04121.JPG

 

[lawsonuw]

I had a 6.5 self propelled Toro mower, which worked fine. I bought a Homelite electric mower and used a simple 1500W inverter to convert 12 volts to the 110 volts AC that the mower needed and basically had a cordless electric. It takes about 1 hour to cut my yard, so the electric mower can do it in one charge. The picture is a bit old now because I don't use (2) 12V 12AH batteries now, I use a single 12V 33AH battery (AGM). The irony is, the electric mower, even with that big AGM battery is still half as heavy as my Toro Gas mower was. So even though the electric wasn't self-propelled, it was light enough to push around with one hand, so the weight was really no longer a problem. In fact, it's so light that when I use the mulching bag, it can get so full of grass clippings as to cause the mower to tip over backwards, LOL. I know when to empty it at least.

The electric mower always starts at the flip of the switch, makes about as much noise as a dust buster and I can easily tip the mower on it's side to clean the blades. Unlike my gas mower, it would spill gas and crap everywhere if it wasn't sitting straight up. The gas mower (as with all of them) always has the problem of hitting grass that is too tall or thick and killing the motor. On the electric mower (which is only 1200 watts, barely 1.5HP), I have yet to encounter grass high enough or thick enough to stall the motor out. Actually, when it gets THAT much grass, it starts to jerk the mower around because the motor seems as though it's invincible from stopping. So I know then to cut the 1 M high grass a little slower and scrap out the tons of wet grass clogging up the blades.

I sold the 6.5 HP Toro mower long ago. It was cheaper to put the electric mower together than it was to buy the gas mower. So I recovered about $100 from the sale of the gas mower and kept the electric mower. The electric mower is still going strong and I always get the usual stares from the neighbors when I'm pushing around my electric mower with one hand while talking on the phone because it's quiet enough to talk to them. 8)

It's also fun to stop the mower, pick up a stick or something, pull the switch and be off again cutting grass without missing a beat.

You know, I bet all those tools in the video have series wound universal motors. As such I'd bet they'd all run at full power on 80-100 volts DC, and darn near full power on 72 volts DC. (might have to upgrade the switches as DC is harder on switch contacts) Got a spare e-bike pack laying around?

Lawson

 

[pwbset]

Well I bought the HomeLite electric mower last night and this afternoon will do a runtime test. It came with 20ah batts so I'm thinking they upgraded that since knight's post where he said 12ah. I've got about .2 acres of lawn to cut so I'm thinking I'll be just fine with 20ah. When they die I'll run it on konion power. Now I can grow food in the yard without spraying it with gas and oil. Sweet.

 

[AndyH]

Lithium conversion in progress! The stock Panasonic 12V20Ah SLA batteries lasted five years but they're gone for good now. The mower has ben an excellent match for the .11 acre lot, but it's heavy at about 80 lbs. But we know there's a fix for that.

View attachment cmm1000V4.jpg

Moving from 30lbs of lead to 8 lbs of LiFePO4 makes this an entirely new mower in the handling department! The mower has a no-load draw of about 12A, and Texas grass isn't nearly as lush as in other parts of the world, so this 10Ah pack should provide more than the 30 minutes of needed run-time.

The stock SLA charger should provide a bit of under charge. The G/F BMS will keep things under control just in case, and provide an upgrade path for a real charger later. I'm building the active-cutoff portion of one of Gary Goodrum's LVC boards and hoping that the 4110 MOSFETs will handle the motor-start surge of about 190A until the blades are spinning.

 

[knightmb]

Lithium conversion in progress! The stock Panasonic 12V20Ah SLA batteries lasted five years but they're gone for good now. The mower has ben an excellent match for the .11 acre lot, but it's heavy at about 80 lbs. But we know there's a fix for that.



Moving from 30lbs of lead to 8 lbs of LiFePO4 makes this an entirely new mower in the handling department! The mower has a no-load draw of about 12A, and Texas grass isn't nearly as lush as in other parts of the world, so this 10Ah pack should provide more than the 30 minutes of needed run-time.

The stock SLA charger should provide a bit of under charge. The G/F BMS will keep things under control just in case, and provide an upgrade path for a real charger later. I'm building the active-cutoff portion of one of Gary Goodrum's LVC boards and hoping that the 4110 MOSFETs will handle the motor-start surge of about 190A until the blades are spinning.

I see you had the cover off, was it an AC electric mower or DC electric mower? I've often wondered if mine is using a brushless AC motor or not, just haven't taken it apart to find out yet.

 

[dnmun]

it is a brushed 24V motor. i got one free off CL and was able to make it work, but gave it to bill bates last year. there is no controller, just a big switch and a coil of wire from the spin down when the switch opens.

i saw andy had panasonics in his, mine had yuesa 18Ah. they were lame, and bill took 2 of the 18Ah packs which he had left after converting the velo to lifepo4, and he swapped out the old packs for his and it runs fine now. i think the battery powered mowers get real neglect because people don't recharge the mower immediately, instead wait until the next time they mow and then charge. or push it to mow when the pack is discharged and overdischarge the pack easily.

 

[Link]

I see you had the cover off, was it an AC electric mower or DC electric mower? I've often wondered if mine is using a brushless AC motor or not, just haven't taken it apart to find out yet.

It's a DC. I had the same mower in a different color. Still have the motor lying around, but there's something wrong with the bearings.

And that thing weighed 80lbs? Must have been stronger than I thought I was...

 

[Instant Karma]

I converted a corded AC B&D mower to battery power 4 years ago because I didn't like messing with the cord and was afraid I get electrocuted by the AC. It runs just fine with 72V of batteries, I use 3 24V 7AH Ni Cads and just put them in a bag and bungee rope them to the mower and can get 2 mowings on just one charge. This is the 7th season with the electric mower and except for replacing the mowing blade twice it's still going strong. The motors on the AC corded mowers are universal like somebody mentioned above but the motor runs better on direct DC from batteries rather than the dirty AC power that comes out of the rectifier.

 

[Reid Welch]

About .2 acre to mow. No more gas mowers for us. Got a corded B&D (not the flip handle version) with the "12A" motor.
Getting a 100 foot 12ga. two conductor power wire in bright yellow was a trick to find. There is an automatic (hand cranked) cord reel,
I forget its brand name. Have two of them. The yard in back and the courtyard in front are suitable for corded mowing or blowing.

I like the light weight and freedom from batteries, the simplicity and low weight, so, corded works well for me.
I know how to splice the cord if I cut it (which is rare and stupid). It cuts thick Florida grass and weed without bogging at all,
provided the blade is kept sharp.

Batteries? Someday? But Ernie likes this mower; at 78 he can cut the entire back yard as fast as I could do, were I up to even that simple task anymore.

Five years from now the yard will belong to someone else. Let them pass gas or buy batteries. I rewind the hundred feet of cord in less than two minutes, and it never tangles. Love that cord reel jobbie. And 120AC delivers much more power indefinitely than any ready-to-buy battery mower, so far as I know. It's like going from a Dustbuster to a corded vac: you trade convenience for real power.

But maybe, someday...The Final Solution

:wink:

 

[knightmb]

I converted a corded AC B&D mower to battery power 4 years ago because I didn't like messing with the cord and was afraid I get electrocuted by the AC. It runs just fine with 72V of batteries, I use 3 24V 7AH Ni Cads and just put them in a bag and bungee rope them to the mower and can get 2 mowings on just one charge. This is the 7th season with the electric mower and except for replacing the mowing blade twice it's still going strong. The motors on the AC corded mowers are universal like somebody mentioned above but the motor runs better on direct DC from batteries rather than the dirty AC power that comes out of the rectifier.

Yeah, I've been meaning to try that on mine. I figured it must have brushes or otherwise it would just rotate to one position and sit there.

If it's that easy, then I might be able to lighten mine even more with the inverter removed from the picture. Portable 110 outlet is handy though sometimes I might miss it.

 

[AndyH]

Lithium conversion in progress! ...

She's done!

The pack is 8S PSI 40138 cells in assembly blocks. It has a full bottom and short sides made from .030" G10 fibreglass sheet. The G10 is attached to the assembly blocks with 1/2" long sheet metal screws. The battery is the same width as the dead VRLA, so it fits into the styrofoam 'frame' the same way.

View attachment pack_side.jpg

I cut the active cut-off portion from one of Gary Goodrum's break-away LVC boards and put that in the negative cable from the pack. The cut-off board is activated by the LVC signal from the BMS board. The pair of 4110 MOSFETs seem to be fine with the 190A+ start-up current. I did add a diode across the motor to give the MOSFETs a bit of extra protection.

The BMS is standard Goodrum/Fechter with a temporary switch to activate the charge-control portion. (That will go away with a charger upgrade later).

View attachment bms_bottom.jpg
View attachment bms_window.jpg

It's a bit ghetto around the edges, but 22 lbs lighter, more power, and a low-voltage cut are nice additions!