# dcb's GE E10m leaf battery upgrade



## dcb (Dec 5, 2009)

Hola, so I picked up an e10 elec-trak , had really crappy batteries, like 6 ancient t105 sized 6 volts. But had a trailer and a plow, so sounded like a useful tool otherwise.

I was looking at options, i.e. costco 850284 (g2 interstate 6v) and realized I'd be changing 'em out in 3 years and $500.

So I had nissan leaf lithium cells I was *going* to convert to 15v modules, for a 225v 30ah motorcycle, but never sorted out a good way to do that at the desired power levels, so they needed a home, and this turned out to be a good fit. You can see one of the modules has been pretty much hacked up.

This is 15 modules (7.5v 60ah per module) 3 modules in parallel, 5 groups in series, so 180ah and 37.5v. The original was 36v.

I'm experimenting with the onboard charger for now, it seems to pump electrons just fine though, and has a timer. More refinement would be good of course, but it is functioning, and there's lawns that need mowing  @36v it was drawing 13A from the wall, @38v it was down to 10, a little bit of warm air coming out of the charger tunnel.

The modules get a good bit of compression from the battery box/shimming and the front box is now empty. It lost about 351 pounds in the conversion.

Need an ammeter/voltmeter for starters. And a better charge control, maybe something resembling a bms at some point.

edit, here is what I use for balance/voltage monitoring http://www.diyelectriccar.com/forum...-pack-balance-monitor-batt-bridge-165953.html


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## dcb (Dec 5, 2009)

so I was knocking down some very tall grass with the deck up and the left deck motor quit (right was replaced at some point). I have a spare parts motor, will combine them for now.

I had quit charging @ 4.08 volts on the highest battery, the whole pack still reads about 40 volts after about 1/3 acre of serious (and wet) grass, it has plenty of capacity and power.

I interrupted the initial charge to install a 100a shunt in the front box, where I just have the leads bolted together (don't know how accurate it is), which was indicating about 11.5mv, or 15.3 battery amps while the wall was at 7.5A (probably not true rms). @ 40v and 120v respectively would make the built in charger about %68 efficient.


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## electron bom (Dec 4, 2014)

I've never heard of an elec-track e10 before, but I've always thought an electric riding mower would be neat. 351lbs weight savings on that little tractor is amazing!  Nice Job!


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## onegreenev (May 18, 2012)

Excellent snag on the E10 mower. Nice use of Leaf modules.  I'm jealous, been looking for one for years.


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