Ben Nelson's Electro-Metro Build thread

[bennelson]

I did a little more work on the Metro this weekend.

I've stil had that LP generator mounted in the back, even though I haven't been using it. The Propane/Plug-In Hybrid setup worked well as a proof-of-concept, but in execution, it left a few things to be desired.

The main thing is that it is an engine and MAKES NOISE! Beyond, that, I got the generator in non-running condition, but never really got it to run quite how it was supposed to. I had also returned a few batteries to the Milwaukee Makerspace for this summer's Power Wheels Racing in Detroit.

Those things, combined with the fact that I was mostly working on the motorcycle this summer, meant that the Geo didn't get much use.

But as winter approaches, the cycle will go into storage, and I need some four-wheeled fossil-fuel-free transportation.

By removing the generator, it free's up some space for more batteries, so yesterday, I pulled it out.



Previously, I had used some bed frame to build the rack that the batteries went on, back when I originally had them in the cargo area. That bed-frame later became the suspension frame for the generator, so I needed some new material to mount batteries in the back.

I pulled out some angle iron, and spent some time cutting it to length, and bolting it into the car to span the spare tire well in the cargo area of the car. Once done, I loaded 5 batteries into the back, and threw chargers on them. I did NOT have additional battery cables (I'll still need to make some) nor do I yet have a top tie-down, but just putting the batteries in there lets me test location, suspension, and spacing.

Here's a side view of the car with 5 batteries in the back seat battery box, and an additional 5 in the cargo area. Ride height looks about right.



The main reason I want higher voltage isn't for speed (although that's not a bad side-effect...) but rather for range, and not discharging the batteries as deeply. The other thing is that there are some electronics that only operate at certain voltages. For example, this:


This is a salvaged 12V power supply that will run off either AC OR DC power, as long as that DC power is at least 110V. The 12V supply can then provide power to my 12V accessory battery. That battery was used when I got it, and never in great condition. Add the fact that it's a starting battery, NOT a deep-cycle and I should count myself lucky that it has performed as well as it has. (The car features daytime running lights. Good for safety, bad for the poor battery!)
A 15 amp 12V power supply should be more than enough to power the headlights and other 12v electrical loads.

While over at the Milwaukee Makerspace today, I rigged the power supply up to house AC power to test the output.



While the initial output of the power supply was 12.5V, a quick adjustment of a potentiometer, just below the green power indicator light, showed that the device could output anywhere from 9.5 up to 14.5V!

I'll most likely rig it up to my accessory battery somewhere in the range of 13+V to act as a charger.



The power supply is whatever the opposite of weather-proof is. I was afraid to even have a beverage near it, as the entire thing is nothing but air-holes! I'll need to make sure it's protected from weather, but not completely sealed up so it doesn't overheat. The easiest way to do that may just be to mount it in the back of the car somewhere.

[bennelson]

Fairly recently, I threw another 5 batteries in the back of the car.

I more or less rebuilt the "bedframe" battery rack. With some other material this time though, as the actual bedframe became the rack for the LP generator.

I just around in my pile of battery cables and had just enough to connect all the batteries, although not all the cables are the same length. They are all matching 2/0 thickness.

I talked with Paul Holmes a while back, and he was working on a 1000 Amp version of the Open Revolt. He sent it to me, and I got it in the mail a few days ago. Today, I connected it up to the car. Physically, it's the same 8" width as the original 500 Amp controller, but it's a bit longer and heavier, which you might expect of something capable of double the power.

Speaking of power.....
I now have 11 x 12V batteries in the Metro. That's 132V nominal. (Take THAT Forkenswift! ) Now if I have the ability to take 1000 amps from that, that's 1000A x 132V = 132KW = about 177 Horsepower.
According to Wikipedia, the 3-cylinder Geo engine was 55HP/41KW
So, in theory, with the new controller and 11 batteries, I have a car with TRIPLE the power of a stock vehicle!

And no engine noise. So burning rubber instead of gasoline is quickly becoming, more of a reality, instead of just an expression!

So far, the new controller is just installed in sort of a test mode. I still need to finish the case, and build a real solid mount for it in the car. I also need to tweak the settings. As it is right now, barely touching the accelerator shoots the car down the road pretty quick.

"Hot-Rod mode" could be fun, but I don't think the motor mounts are going to like it. And it's not like I haven't gotten a speeding ticket in this car before..

Well, at least this time I could really earn it.

I had to dig around to find my old salvaged tablet PC running Windows XP and RTD Explorer. Once I found it, it connected up to the controller no problem. I had to remember how to do a couple of commands, but I was able to get the car and the computer to talk to each other. I even set battery amperage limiting to 300 amps. I only have a 300 amp fuse in the car right now, and don't want to get stuck on the side of the road just from pressing the accelerator too hard!

[mechman600]

Eagerly anticipating an electric smoke show!!
(from the tires, of course)

[MPaulHolmes]

It's actually more like 132volts * 1175amps, since I did a booboo with calibrating the current sensor. So, about 208 HP, but who's counting. haha. We'll get that stupid throttle worked out!

[MetroMPG]

You, sir, are a crazy person.

"Black Zombie"? Don't twist off too many axles, now!

Awaiting the updates.

[bennelson]

The instructional DVD that I made, based on the construction of this car - BUILD YOUR OWN ELECTRIC CAR: CHEAP - is now available at Amazon.com

If you have bought the DVD, or just love what I have done on this project and been entertained or inspired, please visit Amazon and leave a POSITIVE REVIEW of the DVD!

Click HERE to leave a review at Amazon.com!

.

[bennelson]

Another article somebody wrote on my projects -

Read it HERE.

[MPaulHolmes]

Good article!

[bennelson]

Dear Friends,

I've been giving it some thought and I've decided it's time to SELL THE ELECTRO-METRO!

Yes, you heard me right. Lot's of blood, sweat, and tears went into that project.

However, I'm seeing that it's not being put to the best of use anymore. Even with my broken ankle last summer, I was finding myself riding the electric motorcycle in good weather, and if it was bad, I had the option of borrowing my wife's Hymotion Prius and running it in EV mode.

I also have a project Mitsubishi i-MiEV in my garage and I'm finally really getting rolling on my SUPERTRUCK DIY Plug-In Hybrid Pickup truck project.

So, it's time to say goodbye to the Metro, to make a little more time and space in my life for more ambitious projects!

I'd like $2000 for the car. What exactly comes with it is negotiable. At this point, I think I want to use the Open Revolt controller for the pickup truck and would swap it out for my original 72V Curtis controller. Running at only 72V, the car looks stock with all the batteries in the under-the-back-seat battery box and under the hood.

Daytime running lights, seat belts, driver and passenger air-bags are all stock. None of the safety systems have been altered. (I've driven my baby around in this car, I want it to be safe.) Standard insurance, regular clean title.

The car comes with a tow bar and is designed to be able to get flat towed. It's in the greater Milwaukee, Wisconsin, U.S.A. area and tows fine with any pickup truck.

The entire project is well documented in this thread, in the BUILD YOUR OWN ELECTRIC CAR instructional DVD (free copy with purchase of car!) and at Instructables.com

I also have a few spare parts, such as the original transmission and a good-condition spare windshield.

This car should go to somebody who is "hands-on" and has some experience with the basics of electricity, and knows how to use a multimeter.
I'd love to see it go to somebody on this forum, as I know it would go to the best use!

The car is really designed for city use. About a 20-mile range. 45mph top speed on 72V system. 73mph top speed on 144V.

For any more general info, ask right here in this thread. If you are interested and want to contact me directly, please use the private message system of this forum.

Rest assured that I will continue my work in DIY grass-roots hard-core clean transportation! You can see me this summer at the MREA, and two different Mother Earth Fairs, along with other smaller events and you can also keep up with my at my blog at 300MPG.org

[mechman600]

It will be a sad day when you sell the Electro-Metro!
That car was one of the main inspirations for my project.

At least the car will get a lot more use than it does now, and hopefully someone here buys it so it "stays in the family", so to speak.