oatnet
1 MW
I've had a 1974 VW Camper Bus (Bay Window, transporter, whatever) for years. Recently I've mostly just driven it from one side of the street to the other for street cleaning. Last week it caught fire while I was doing that. Unlike most VW fuel-line fires, it was an electrical problem - appropriate.
I wanted to convert it to electric years ago, it is a big light sturdy platform powered by a mere 66hp ICE. Didik mentioned that the only most successful conversions he had seen were on VW Bus's for those very reasons ( http://www.didik.com/criticalev.htm ). After a thorough analysis I decided lead acid's weight required too many tradeoffs, especially if it meant killing a perfectly viable ICE road vehicle that had been coast-to-coast several times.
Last year I almost bought 90ah Thundersky cells to do it, they had enough w/h to do my target commute but they were unproven and too expensive to gamble on. plus they only do 3c and 270 amps would be lame on hills. Larger cells would make the project cost too much to interest me. I focused on doing a lightweight vehicle instead, which lead me to my Comuta-Car project.
Then the Fire. At first I thought I would have to scrap the Bus, the comuta-car project was in progress in the garage, I didn't want to sink time/money into a 2nd fullblown EV project, and if I don't move the bus every week for cleaning I get parking tickets. Then I realized - that is as far as it has to go right now, across the street and back.
If I put in a motor, adaptor plate, and control system into it, then a 500wh string of a123's should be up to the task of crossing the street. Then I can resume the ComutaCar project. I can use the 48v80ah ComutaCar pack in the bus to see how much current it draws and get a better idea of just how big a pack I need. Plus I can prove out the Headway cells in the Comuta before splurging on a huge pack. In the worst case I can move the motor/adaptor plate/controller to a Vw Bug chassis and build a lightweight vehicle or just sell them.
So today I bought a Kelly KDH14500B controller on ebay, 144v500a = 72kw boost and 29kw continuous. It's a month old, I paid $798 for it, about 30% off Kelly's price.
I bought a brand-new ADC FB1-4001a 9" motor on eBay for $1274, @25% off street price. This model has a tailshaft so I could stick a generator on the tail and use it to achieve regen on a series motor.
I am buying a CanEv adaptor plate. The ADC motor's base bolts to the plate and the plate bolts to any aircooled vw tranny. The Flywheel/Pressure plate is bolted to a hub that is keyed to the ADC's motor shaft.
The rest is just building the control/safety system, which I have laid out and I'll post tomorrow.
Most Lead-Acid bus conversions add 1000-1500lbs over stock. According to my list of what mass is coming out and what is going in, the LiFePO4 bus will be merely 35 lbs over stock when equipped with a 100v100ah pack. Since I don't have to push all that extra mass around, I have no idea how any wh/m it will actually consume. That is where the little 48v ComutaCar pack will come in handy - the RPMs will be low but I should still be able to get a rough baseline.
Fun detail - the vw transporter has a special enclosed, protected chamber for the gas tank. I think that space will be big enough to hold an entire 100v100ah LiFeP04 pack, making for a very clean, safe install.
-JD