I can't tell you about the Leaf packs, but when I built my electric lawn
tractor, I wound up with a used Volt pack from HybridAutoCenter
Specifically the 48v/47ah Volt pack -
It was $430 plus freight, which brought the price to around $500.
I also bought a low end BMS from them for $150, and $165 for a 10amp charger.
The BMS does balancing and prevents overcharge, but the operator (me) is
on the hook to not over-discharge the batteries. I just watch the
12s pack of Volt modules.
Mine has no coolant, but was still bolted together.
The charger shuts off at 50V. I stop cutting operations at 42V. When
mowing and it drops below 42V, shut the mower deck off and the battery
voltage recovers to ~44V and there's plenty left to drive around and
(I also use it to plow snow in the winter - the electric tractor has never
failed to start, even at -20F)
I'm use the Motoenergy motor. I estimate a 100amp draw average while
mowing - my 2kwh pack gets me 20 minutes of grass cutting, give or take.
That's enough to cut the front yard or the back yard at a decent pace, or
both if I do it all in 5th gear. :D
Charger takes several hours - I think 8 or so - to restore the battery.
It is short enough that I can mow first thing in the morning and do it
again in the late afternoon - but also long enough that I can cut the
front yard one evening and not feel guilty about letting it charge
overnight and resuming the next day.
The motor is a permanent magnet, rated at "48v" and does just fine.
I keep toying with getting a second 2kwh pack and paralleling them. The
current pack sits up front, between the grille and motor. I have room for
a second pack between the motor and steering column, still under the hood
- and also, I think, room under the seat where the starter battery used to
be, above the pulley and main drivebelt for the transaxle.
My biggest issue with the 12S Volt pack - I had hoped to run lead, with
multiple taps at 12, 18, and 24V available so I could use the tractor as a
power supply for my DC spool-gun welder. Drive to the location. Hook the
welder to the supply, weld, drive back. Unfortunately, 48V is not only
"too much" but beyond the spool-gun's limits as well. (18V is probably
the right voltage for general field welding).
Perhaps I could tap off the series-connecting "foil" connections on the
top of the battery back, but I haven't been that ambitious.
I used a 48-->12Vdc converter to run the head lights, and provide a power
port for field-operation of the amateur radios - but haven't found an
inexpensive 48->18 solution that supplies enough current for the welder.
I'll live with it. :)
Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)