DIY Volt Hybrid - Open ReVolt style

[bennelson]

I'm still trying to fiugre out the best location/position for mounting the propane tank.

One thing I was wondering about was maybe having the generator inside, but the tank mounted outside.

I got some work done today on a big bracket to bolt the generator down to the inside back of the Metro.

There really isn't any room for me to cut down through the spare tire wheel well for more space. It's all suspension under there. It's a small car, so there's just not a lot of space for things.

[cyclist916]

I like the concept but please just call it a series hybrid.
I dunno, the way GM has done it just seems to reinforce the need for a ICE engine.
But also sticking to them by opening it up is nice.

[bennelson]

Got some more work done on the project yesterday.

Using some scrap metal, I measured, cut, and welded a frame for the generator. This frame spans the spare tire well. The generator then sits on/in the frame, with part of the generator hanging down further into the spare tire well.



The material I used was old bed frame. Part of this rack was what I originally used for mounting my batteries when I originally had the batteries in the trunk area of the car. That material cuts OK with a cut-off blade on an angle grinder, but it is THE WORST to drill a hole through!







I also noticed that the drain plug holes in the bottom of the car match up well with the size of the exhaust and muffler. It seemed like a simple matter to run the exhaust straight out the bottom.



Also, for a few months now, my BC-20 battery charger has been acting up. (Since then, I have been doing individual battery charging - which works fine, but it's a pain in the butt!) The problem with the charger is that it very quickly tapers off amperage - almost as though the charger works fine, but thinks the batteries are charged when they aren't.

Since the Milwaukee Makerspace is now more or less set up, the Electronics Club has been meeting again. So, I took my charger down there to get some help from some friends.

Here's the charger opened up.


The only obvious problem was this charred resistor.


That resistor is in-line with the VOLTAGE adjustment on the charger, so it would make sense that the resistor wasn't working, based on how the charger was acting.

We had to do some guestimating and logic to figure out what the value of the resistor would be. (Couldn't read the color codes. Ash is not a color.)

I am NOT a master solderer. It must have taken me an hour to remove the older resistor, clean out the solder, and add the new one. The trace on the one side came off with the old resistor. So, some sort of jumper would be needed to complete the circuit. I left the leg of the new resistor long, pulled it THROUGH the board, and it JUST BARELY reached the next solder pad.



I also converted the output of the charger to a 50 amp Anderson connector. This will make it easier to take the charger in and out, or use it with other projects.



While at the MakerSpace, I also picked up some 6 ga wire. I need an ignition cable to run from the accessory battery to the electric starter on the generator. I plan to use the car's "crank" position on the key to run a relay, which will ground the remote starter pin on the generator. That activates the remote start feature.

I will have an electric car with 3 key positions - off, EV system ON, and START the Generator.

I'm still not sure exactly where I want to mount the propane tank.

[MetroMPG]

So the charger works again?

I like the muffler dangling below the car. Might want to ensure it's "sacrificial" in the way you connect it, just in case.

[bennelson]

Originally Posted by MetroMPG

So the charger works again?

I don't really know if it does or not. I haven't hooked the charger up to the battery pack yet. I didn't get home from Electronics Night until about 11pm.

I will be working on the project some more this afternoon.

You really need an actual battery pack to test a charger on. I'm really hoping it works! The trouble with the charger is that the amperage would drop down really fast. However, with the changing battery pack voltage of a hybrid system, it seems like it would "reboot" or trick the charger into keeping on with the full amperage. So, even with the charger "broken" for overnight EV charging, it would still work as a power controller for the hybrid.

I just really hope it works though. Recharging with three Sears 12V chargers gets to be a big pain. I have to have the battery box cover off, it looks really messy, and I have to manually move all the charger alligator clamps half-way through the total charging cycle.

As for the muffler - it doesn't stick down very far. I'm not even sure that it sticks down any further than the original car muffler would have. Also, the back of the car still rides a bit higher than stock because of my truck springs in the rear. I'll make sure to measure it today.

[bennelson]

New Video.
Just showing the generator mounting bracket.

http://www.youtube.com/watch?v=31snuDIk28I

[NeilBlanchard]

It looks like several other components are getting pretty hot; nearby that cooked resistor? And the traces for some things are also getting warm?

[bennelson]

I couldn't say if any other components are getting warm. I don't stick my fingers in there to find out while it's running!

It's a pretty old charger - they haven't made these in some time (which means there is no such thing as tech support....)

[Dr. Jerryrigger]

Nice job with the bracket!

Tanks on the outside shouldn't be to hard, unless you want it to be...
You could just attach the tank holder off your old RV to the bumper. You should look up the DOT rules about transporting propane before making anything permanent.
Speaking of your RV, what is it? I once had a '69 Shasta it was 18' and it was a heap, but I live in it for nearly six months.

[bennelson]

Some more work done on the project today.

I painted the rack black and bolted it in.


The generator was bolted down to the rack.


The bolts and rack also act as the ground for the generator. I thought I might need to add an additional cable as a ground. I haven't done that yet, the electric start circuit worked great without it, but it might not be a bad idea to add a short ground cable to the car frame anyways.

The the electric start on the generator, I made a new power cable - 6 ga - to run from the car's 12V accessory battery back to the generator.
(I wasn't sure exactly which size cable to use for the battery cable. I found some 6 ga. When I checked later, I realized that on the generator itself, it is a 6 ga cable that goes from the solenoid to the starter.)


I stopped at the hardware store and got the right lugs for it. I even had heat shrink and color-coded electrical tape! I know, getting fancy, right?
The only thing I didn't have was a crimper for that size. The "smack it with a hammer" method seemed to make a nice solid connection though.

So now the generator with start with the car battery, but more importantly, will CHARGE the battery when the genny is running.

If only there was some way to remotely start the generator while I am already driving the car...

Oh wait, there is!
On the generator is a multi-pin connector for a remote control panel.

Before going to Electronics Night last night. I e-mailed one of my friends the description and this photo of the connector, to see if he could find me the mate to it. He did, so I can now make my own adapter. The certain pin needs to get grounded to turn on the starter.

If only a car had some way to to activate an electric starter...
Hmmm. Well, I wasn't using the "crank" position on my car's ignition (ever since I took the engine out) so I thought why not reuse that?

I took off the lower dashboard to get to the ignition wiring.

I followed the repair manual to find the wire that should run to the key start position. When I found it, I cut away just enough insulation on it to poke it with my multimeter probe. I clipped on some jumpers and tested it with my meter, by turning the key to start.

Sure enough, the meter jumped from 0 to 12V!


Unfortunately, the generator needs a GROUND connection, NOT 12V power to kick on the starter. So, I added a splice connector to the START wire, and ran that to a 12V relay. When the relay kicks on, it connects the remote start pin to the car chassis.


Now, when I put in the key, I have three choices.

1. Off (self-expanatory)
2. E.V. system on (I can drive the car as electric)
3. Start Generator (does not deactivate EV system)

It feels kinda weird to use the starter in an electric car! Also, it's odd to hear engine noise coming from the REAR of a Metro!