Sunday, May 19, 2013

Checking EV project off the list

It has been a long time coming but here it is. If you have been following along it was Jan 7, 2013 that I began the process of dismantling my 1980 Dodge Omni EV that I built in 2002 for transplant into this 2001 Dodge Caravan. It would prove to be a formidable task as the axles would need to be cut and grafted together. Shift linkage would need to be mounted as well as drive for the power steering pump and vacuum for the Caravan's  power brakes. Along the way there were several interruptions but the job was done. Can report that I have the first 10 miles in and all is well so far.

Added a nice little red indicator light to let me know when the shift linkage is in reverse. Very helpful.

Solved the speedometer and odometer problem with my GPS. Nice to know.

With the battery pack being 7 years old (3 years of use in the Omni and 4 years of sitting) I anticipate a replacement will be in the works soon. For now I will put some miles on and collect some data. A full report will be coming this summer.

Until then I think a nice 20 by 24 deck for the Hodan Center in Mineral Point will make a nice new project to work on next.

Monday, May 13, 2013


There was a flash and a little set back in the EV project this week. My attempt to go cheep on the DC to DC converter was soundly rewarded. Things were working just fine with the vacuum pump as the load (9.5 amps) but then when I add the headlights and tail lights (10 amps) to the load, Zzzzzap! Out went the fuse in the converter circuit. Hoping that it was just a load issue I turned off the headlights and tried another fuse. Zzzzzap again. Oh oh this could be trouble and after removing the converter from the circuit and testing it my worst fears were confirmed. The converter was fried. You can see the diode in the lower right corner and there was more damage in other areas.

I had read about the "short" comings of low cost DC to DC converters in the builders manual and now received a lesson. The cost of this education $100.  New $350 converter on order from the EV building experts at Electro Automotive. Live and learn.

Friday, May 3, 2013

Batteries not included

Buying these battery cable ends for the EV conversion project reminded me of the old days when you would buy an electronic product and after taking it out of the package to try it only to find out that the batteries were not included!

I thought those days were long gone and over but to my surprise when I went to my local implement dealer and asked him for a straight, 00,  positive and negative crimp on battery cable ends I was surprised to see they came without bolts. When I asked him if they came with bolts he said, "no they're separate." I said I needed them so he went back into the stockroom and got two. That was only part of the surprise. Then I saw the price! Gees, imagine doing a new conversion and getting these for 16 batteries. I had the 00 wire and shrink tube. Yeks!

So now it is on to the wiring. First the low amperage wiring. Tricky.
 This will be all the components that will be run off the 12 volt DC supply. Because the Caravan has power brakes I will need a vacuum pump and as an up grade to this conversion I will be adding a DC to DC converter from the 96 volt pack to reduce the load on the 12 battery.

Pictured above is just a test run using jumper wires for the circuit that will run the vacuum pump. Boy this is going to be a puzzler for sure.

Next will be the high amperage circuit wiring.
This will hook up the 96 volt traction battery pack to the drive motor and controls. Where's that darn EASY button when you need it?

 Since the vacuum pump and reservoir had to be mounted in the Caravans original battery box I had to build another battery holder and mount it. For now I am using a smaller 12 volt gel cell to see how it works.

Following good safety practices I have installed a fan and vent pipe in the battery box to remove any hydrogen gases given off during charging of the pack.

And so it goes. Slow but steady progress.