EcoRider - riding lawn mower electric conversion

[Daox]

I got a chance to do some mowing with the mower finally! I still haven't resized the pulleys, but it does work great as is. The deck is spinning a bit fast yet and it really shoots the grass out pretty far. It had no problem cutting through ~6 inches of grass!

I had to do all the cutting in 1st gear as 2nd is still too fast. I did notice that when the deck is engaged and you're actually cutting grass, the mower does slow down. So, 1st gear is no longer as fast as I'd like to do actual mowing. So, I will still be resizing the pulleys, but I have a much better feel for how much to resize them now.

Oh yes, I got video this time too.

YouTube - EcoRider In Action

Finally happy Darin?

[MetroMPG]

Nice video!

It doesn't seem that slow. No slower than a push mower anyway. Was that first gear?

You can really see the force of the air coming out the discharge chute.

[Daox]

Yup, the cutting was done in 1st gear. I did try 2nd and it was pretty fast for mowing.

[bennelson]

I love the fact that the mower has full moon hubcaps on the back tires. Very AERO!

I would complain that I would like my Elec-Trak to go a little faster.

Guess that's the difference in gearing between a stock manufactured mower and trying to build one yourself.

Those batteries look like they hold up OK?

[Daox]

The batteries really don't last too long. Once I load them up off of a fresh charge the voltage plummets down to around 35.5V. However, they did last longer last night then they did the other time I had it out. I don't know how long these have been sitting. Perhaps a little exercise will be good for them.

[Christ]

It's alive!

Are those actually moonies on the wheels, or are they weights?

[Daox]

I think they're just moonies. I haven't tried to take them off though.

[Christ]

Originally Posted by Daox

I think they're just moonies. I haven't tried to take them off though.

If you can pick up the assend of the tractor, they're not weights. The smallest weights I know of are 35# per wheel, and most are 55# and higher. I can pick up the rear end of most tractors to about hip height, but if they've got weights, I can only get one tire off the ground.

[beem0]

Good story. I'm new here but like what I see so far!

How do you know when you reach 50% depth of discharge? If you got a hour run time while only taking the batteries down 50% that would be great!

-Ryan

[Daox]

Hello and welcome to ER beem0!

You can monitor battery pack voltage to know when you've gotten down to 50% dod (depth of discharge). Right now, I've just been using a voltmeter across all the batteries. I plan on using an individual LED battery monitor (3 bar graphs basically) very similar to this. A guy from the local electric car club has designed a similar unit and will be making a batch of them.

I've been going over my battery choices and I think I am going to settle on three group 31 12V batteries. These won't give me the run time I really want, but the more I think about it, the less I want to lug around six 6v batteries. The mower is already heavy enough with Ben's three gel cells on it. I don't even want to think about three more batteries of that size. Plus, I have to mount them all too. The group 31 will be rated a tiny bit over 100Ah and give me about a half hour of run time to 50% dod. This is acceptable. I also looked at the numbers, and assuming I used the mower once a week and ran the batteries down to 100% dod, I would still get roughly 11 years out of them. If I went down to 50% dod, I would get 22 y ears. I'd have to double check that though. So, going to 100% dod, and my 1 hour of run time is possible for a hit to the life of the batteries.