EV-1 Conversion

[JCG]

I'd posted on this project (conceptually) a few times in the past, and recent conversations (and PMs) have convinced me that it's time to start a thread outlining what's been going on with a project I'm dividing my time into: conversion of a General Motors EV-1 into a serial hybrid with an ultracapacitor-only electrical storage buffer. Primary energy is to be from a small (25-35 kW) genset which will charge the caps, and the standard EV-1 drivetrain (with a repaired controller) and its 103 kW motor. The car has been here since before I arrived (since 2002), but only recently we've been granted a place to work on it. Here are some photos to get started explaining the project.

The car is in a small fenced-off area in our University's service center (basically a parking garage with some shop equipment that I'm not allowed to use):

These are the immediate tools of the trade. The cardboard box contains the repaired and refurbished motor controller/inverter, which is the biggest key to the whole project. It will accept a DC input voltage range of 200-400 V and is controlled with throttle and braking pots (5 kohm). I'll open the box up once I'm ready to start turning the wheels. For now, I need to work on the 12 V system and getting the caps installed.

Here are the cap modules. Eight total, each 48.6 V and 165 F which will provide a 389 V, 20.6 F series pack. The generator will charge these to about 375 V, leaving head space for regen braking when they are fully generator-charged. Two of the packs I've assembled myself, the other six were purchased as you see them.

Here's the trunk space, in which I hope to fit some kind of ICE and generator pair. It's a deep trunk, but not a tall trunk. That will be an interesting design.

Here's a look under the hood, and a close-up of the motor. The motor is usually concealed underneath the inverter, which is mounted above it when installed.

Here's the small 12 V auxiliary battery, which is kept charged with the DC-DC converter mounted alongside the inverter. The battery had sat around for several years, and was a lost cause.

I replaced that battery and charged it in place.

Supplying the charging voltage to the 12 V bus allowed me to test the vehicle's auxiliary systems. I cracked the startup code and got the radio, lights, and dash working.

One interesting item is the high-voltage service disconnect which was in the cabin. It's basically a pin that was used to connect the series of VRLA batteries that the car used before you'd take out the battery tray. Here's a photo of it sitting on the roof.

The disconnect is supposed to be placed behind the driver's seat. Here's the flap. When I opened it, there was just an empty space behind it rather than an electrical fixture.

Inside: rat manure and chicken bones, which they had dragged up inside the car to eat at their leisure. Cleaning the battery tray out is going to be a pleasure.

Here's a view inside the T-shaped tray. All the VRLA batteries have been removed. This is now the space that I'll use to house the ultracaps. There should be plenty of room.

The battery tray, which I mentioned is T-shaped, drops out from underneath the car. I needed to get the car on jack stands (no lift available) and will drop the tray out after removing all the bolts. Getting any vehicle up on four jack stands is a scary job to do by one's self, especially with only one floor jack to use.

Luckily, I found a method that worked and should be in good shape to drop out the tray soon.

I'm now float charging the auxiliary battery and the next step will be to drop out the tray, clean it, and see what electrical connectors still exist down there. Once I know that, I can re-install the controller and DC-DC converter, then charge the caps up from a rectified 220 VAC source (300 +VDC with capacitor storage) to light up the car and hopefully spin the wheels. It's baby steps for now, but exciting stuff.

 

[sabongi]

awesome buddy!
I thought they were leased, and that GM had took all of them back.

 

[TylerDurden]

Wow.

Looking forward to it.

 

[JCG]

awesome buddy!
I thought they were leased, and that GM had took all of them back.

They say that about 40 were saved from the crushers and donated to universities or museums (the Smithsonian here in DC has one... somewhere). GM did indeed take them all back after the California leases expired. A real sore spot for a lot of people, and it's become a bad PR thing for GM as well.

 

[lutach]

Wow. You have a precious car there. I'll be following this thread.

 

[swbluto]

Sweet! EV1's have an excellent drag coefficient, so it's definitely a good platform for lower power and less capacity demands. (Hills still require so much power from a heavy car, however.)

I wish there existed an available used car with a similar effective drag area. It sounds like the 1988 Honda CRX may come close considering its 55+ mpg ability, though I think that gas rating may have mainly come from its 55 hp engine. :lol:

 

[vanilla ice]

Tiiight car!

IIRC from the brochure the 88-91 crx was .29 and the 88-91 civic hatch was .31.. probably a little on the optimistic side.

 

[Gavin53]

My understanding about the EV1s (A friend of my in LA had one, and there is now one at UMR (MS&T) in Rolla MO where my son in in school) is that GM gave one to the Smithsonian, complete, there is one at a museum in California, and 38 (+/-) were given to universities. The charge controllers and other "critical parts" were removed, and the schools had to promise not to try to reverse engineer the car or put it back the way it was, but have to develop their own technology to run it. So I am very interested in how you got a controller, and whether GM knows. Did the exclusive deal have a time limit? Maybe once they had the Chevy volt going they relaxed a bit on EV1 technology.
The film "Who Killed the Electric Car?" http://en.wikipedia.org/wiki/Who_Killed_the_Electric_Carwith Ed Begley Jr http://www.edbegley.com/environment/ (and my friend http://www.alexandrapaul.com/) tells the story pretty well.

G

 

[John in CR]

It seems almost sacrilegious to turn a plug-in EV into a serial hybrid. I'd have gotten someone to donate a bunch of lithium batteries to the university, engineer a cooling system for the pack, and go. Still, it's an interesting and practical project, so I look forward to your progress reports.

 

[nicobie]

Yes yes yes

 

[JCG]

Wikipedia has the EV-1 listed with a drag coefficient (Cd) of 0.195, and a CdA (drag coefficient multiplied by frontal area) of 0.367 square meters, which they say are bests for "production cars." It certainly is a slick design. I think it's great that folks here like the way this car looks just from its functionality; there are some mechanical engineers around here that tell me it's ugly. To me (and I bet, to a lot of people here), its beauty is in its achievement of good function (like low drag).

Gavin, you're right about those details for donated EV-1s. That's actually part of the reason I can't turn it back into another straight-up EV with lithium batteries (although such a car would easily get 300 mi range). The controller was repaired last fall and returned around Christmas. No, E-santa did not repair it and bring it to be on his electric sleigh It's now got a full vector-control setup which is much better than what the car originally had (kind of like an advanced VFD with speed feedback info to adjust torque and excitation currents at low speed). Can't wait to try it out.

 

[John in CR]

Regarding the looks, for me it was always something about how that rear wheel was covered that seemed awkward in the looks department. I'm sure there's something that can be done without harming the aero. Just something different with the paint low in the rear could fix the issue and make the look even more sleek and aero. There's just something as is that feels like a '70's attempt at futuristic.

I played around with it for a few minutes in paints, and something other than that all one color paint job will do the trick. Go hook up with a hot artsy chick (eco geeks are really "in" now anyway) over in graphics design, and give this car a paint job it deserves. It's the most aero car ever, so make it look that way.

I always thought the looks issue was a big part of why the car never went anywhere. Someone high up just didn't like the look, and when added to all the conspiracy reasons, it got shit canned.

Oh, and send an email to Big O. With the gov't now owning a big chunk of GM, and full electrics are the future, I'm sure it would be easy to get approval to refit/improve the EV1 to become the EV1.1 or EV2.

 

[liveforphysics]

Do you have ideas on the gasoline or diesel engine choice yet?

Industrial engines, passenger car engines, generator engines, etc are always manifolded, ported, valve job angled, and CR'd to provide maximum longevity at the most minimal manufacturing costs.

In this application where at least 25-35% of the mechanical energy converts will be wasted in inefficiency from going through the generator to the caps, to the controller into the motor and out to the wheels, I think I could help you recover a portion of these losses in the form of lowered BSFC's on the engine through racing engine design techniques.

There are always low hanging fruit in production engine designs to be easily harvested and lower BSFCs.

 

[Ariane]

It seems almost sacrilegious to turn a plug-in EV into a serial hybrid. I'd have gotten someone to donate a bunch of lithium batteries to the university, engineer a cooling system for the pack, and go. Still, it's an interesting and practical project, so I look forward to your progress reports.

+1 Wow simply amazing

Black Arrow

 

[Arlo1]

Wow very cool. I think the plug in hybrid is the car for right now short daily trips are all on electricity and longer trips are with a generator. Hell I am realy concidering finding a 1000 watt generator for my bmx to make it a hybride for longer trips! I have seen they are working on a new typ of lipo that will quick charge (ie a car could be charged in a few minutes) but I have seen no proof as of yet. The charge time for a given batery is what realy holds us back from a full electric revalution!

 

[pwbset]

Niiiiice. So ahead of it's time. GM/BigOil should rot in hell for what they did to this beauty. Can't wait to see the outcome of your project! A PM of your solo jackstand process would be appreciated as I've been trying to figure out how to do it with a '72 VW Campmobile without killing myself.

 

[JCG]

Thanks all, I'll try to tackle a couple of comments before the next little update here.

Go hook up with a hot artsy chick (eco geeks are really "in" now anyway) over in graphics design, and give this car a paint job it deserves.

Oh, and send an email to Big O. With the gov't now owning a big chunk of GM, and full electrics are the future, I'm sure it would be easy to get approval to refit/improve the EV1 to become the EV1.1 or EV2.

Ha! Good news - my wife is both artsy and crafty. As for aid, I'm getting some help from key people in the DC area electric vehicle enthusiast's group (EVA/DC) and there are even still some "benefactors" for our School of Engineering from GM. They aren't giving money right now, but I think I can convince them that they owe it to everyone...

Do you have ideas on the gasoline or diesel engine choice yet?

Hi Luke, still shooting for an ammonia-powered spark ignition engine that will run at around 20:1. I have a friend in Michigan working with me on this at Eliminator Products. I think it'll be fuel-flexible (diesel, propane, or ammonia) but that's a job for this summer. The generator head needs to be rated around 30 kWe or so. With luck and those high compression ratios, we'll be knocking on the door of 50% efficiencies (early dyno tests confirm). We really just need it to fit in the trunk.

I have seen they are working on a new typ of lipo that will quick charge (ie a car could be charged in a few minutes) but I have seen no proof as of yet.

I think I've read about this recently - the SCiB battery from Toshiba? Worth keeping an eye on, certainly.

pwbset, no reason to not post the four jack stand method here. It's not bulletproof, but worked here on a relatively flat concrete slab.

1) raise driver's side (DS) front, first jack stand under front DS axle.
2) raise DS rear, second jack stand under DS rear suspension point. (Note: this the most dangerous time. The stands must be as low as possible to keep the car from rolling where you're about to stand.)
3) raise passenger's side (PS) front, third jack stand under front PS axle. When you do this, the floor jack should be at a non-perpendicular angle to the car's sidewall, as it may try to roll towards you when the front tire comes up. Also, check jack stand #2 often as the car may "float" above the stand you put there earlier as you get the PS raised higher.
4) raise PS rear, fourth jack stand under PS rear suspension point. Let the floor jack down slowly, realigning the rear jack stands as needed. The front jack stands should stay put.

Again, be careful! I'll put EV-1 updates in the next post.

 

[JCG]

Ok, time for more photos. Last night I went about taking the battery tray out of the car. I was not looking forward to how filthy it was going to be, but it had to be done. The first step was removing the air shields from the middle and rear of the car, which covered part of the tray edges. Here they are after extraction. You can kind of see the t-shape between the three.

The battery tray is a heavy-duty plastic form reinforced with a metal framework above it. Here's a view under the car with the air shields removed.

I didn't have a lift table that would fit under the car at this height, so I estimated the centroid and put the floor jack underneath to let it down slowly after taking off the last couple of bolts.

I slightly "misunderestimated" the centroid, but the whole thing dropped out well once I got the jack out of the way.

Here's the tray. Completely empty...

Except for more rat crap, plastic bag pieces, and chicken bones. Thank you, rattus norvegicus.

Good advice from the top cover.

I took off the top cover, cleaned out the tray a bit (more yet to be done - I want a hose and bleach), and tested the fit of the ultracap module in the slots. The fit is not perfect; I'll need to do some cutting/grinding.

Now for the bad news - when I examined the underside of the car with the tray removed, it was empty. When they took the batteries, they took it all - modules, cables, fuse/fuse holder, disconnect plug, and main battery connector. Looks like I have some shopping to do.

 

[Ariane]

Hi,

I read that the EV1 project had started with the purchase of this plan (Urba electric car see below) which dates back several years and strangely we find the same T configuration for the battery tray, very nice pictures indeed and information is really cool!

http://www.rqriley.com/urba-e.html

Black Arrow

 

[vanilla ice]

If there is a legal requirement for non-pure electric, but you did want a full EV.. set it up as a serial hybrid with a 25cc Subaru Robin engine!

 

[JCG]

Black Arrow - neat! Thanks for that webpage. I love reading about the EVs that came to the forefront after the first oil shock.

Vanilla - ha, that would definitely fit in the trunk! Nice one.

 

[paultrafalgar]

Hi Luke, still shooting for an ammonia-powered spark ignition engine that will run at around 20:1. I have a friend in Michigan working with me on this at Eliminator Products. I think it'll be fuel-flexible (diesel, propane, or ammonia) but that's a job for this summer. The generator head needs to be rated around 30 kWe or so. With luck and those high compression ratios, we'll be knocking on the door of 50% efficiencies (early dyno tests confirm). We really just need it to fit in the trunk.

I have a feeling I've pointed you at this before, but here goes: your mention of ammonia reminded my of Amminex:
http://www.amminex.net/
They are storing ammonia in a salt format and then disassociating it with heat and feeding the NH3 to a fuel cell. Maybe you could just use the first stage and apply that to your "ammonia-powered spark ignition engine". I am not sure if they have purchaseable product yet.
Edit: a reference to ammonia engines here:
http://www.voxsolaris.com/nh3driver.html

 

[lutach]

Have you thought about contacting Ovonic for the batteries?

 

[lutach]

If you are set on a generator, see if Capstone can help you out.

 

[JEB]

A friend of mine has a GM electric truck, they did not crush them (he has a ford, and gm) maybe the controllers were close to being alike in EV 1. The parts, and the (private) support for the gm seem to be going away.