I'm not even going there... ;)

I thought he was a making a GT6-EV, though I'd prob go for the spitfire, in fact I recently saw an EV kit for one.

You're right. GT6. Excuse my ignorance, but are they not the same chassis, one hard top, one convertible?

...and a 6 vs. a 4 cyl.

Vid
 

I just had a chance to watch the vid (sorry a bit late -- couldn't do it at work :o )

I love unsolicited reaction by the guys on the street when it's explained as electric.

Bystander: "Bull****. Really? Awesome!"

Meanwhile back at the repair car, $20 is exchanged for an "I told you so" between buddies. :D

BTW, do you cut your own vids? Good background music.

So regarding the battery pack inequalities, what can be done (cheaply and easily) to prevent this problem?

Do you need all batts to run? ...or can you run on x-number until discharged, switch to the next set, etc (or would that discharge them too quickly?) Or you could alternate among them -- guess this would let some "rest" while others were in use, but put a lot more strain on the cables. ...would probably require a series of heavy-duty solenoids or relays.

Do you (or have plans to install) a Voltage readout inside?

OK, I'm done with my 20-questions :)

Keep up the great stuff.

-Rick

OK, so what Metro parts are leftover to sell?

Not enough to pay for replacing the batteries we're sure to murder as we figure all of this out!

Been following this for a while now and thought I'd chime in. Firstly, congratulations on what is shaping up to be a fantastic conversion, and on an affordable budget too! Now about those dodgey flooded batteries. I suggest you buy a hydrometer (couple of bucks), battery load tester ($50) and build yourself a desulphator or two (about $20 worth of parts each).

I just finished my second one, which is also my first ever attempt at etching a PCB. I've been testing on a 220CCA 12V flooded battery. Over the course of a week or so the specific gravity of the electrolyte in the cells has shown improvement (moving from "Fair" into "Good") which is enough to make me think this thing actually works.

A desulphator is by no means a magic bullet, it can't recover all batteries, and the one I built is quite slow - we're talking progress measured in weeks or months, not hours and days. But, you don't seem to be in too much of a rush, you've got a great supply of cheap/free batteries at your disposal so I'd say it's worth a shot.

The plans for the desulphator I built are here: https://www.shaka.com/~kalepa/lowpower.htm

Here's an article by the inventor describing how it works:
https://homepower.com/files/desulfator.pdf

There is a low activity forum as well. I didn't post there, but by reading through the messages you can learn a lot:
https://p198.ezboard.com/Lead-Acid-Ba...erydesulfation

The Alastair Couper plans @ https://www.shaka.com/~kalepa/lowpower.htm are for 12V batteries, for 6V, simply double R2 to 44k. I strongly suggest anyone contemplating building one reads this: https://www.shaka.com/~kalepa/faq.htm There are kits available too if you just want to solder one up.

If you're considering a commercial solution, the only one I've heard of that is reported to actually do anything is from: https://www.batterylifesaver.com. I can't speak for or against it, but I can say I bought one of these https://www.batterylifeplus.com/pulse.html and it didn't do anything, while the one I built myself for much less has produced measureable results. I'm cautiously optomistic.

Anyway, good luck and I look forward to more updates!

Cheers,
Ash

Nice exposé by Jerry at evconvert.com

Ash: thanks very much for chiming in with that info & those links. I had a quick look through. Will delve in further, later. I did buy a hydrometer, but haven't tried it yet (been relying on the DMM alone to this point).

SW: Jerry's funny. For all the "Forkenlookers" out there...

No worries. I found it pretty heavy going (I'm an electronics dunce) but over the course of about a month I've progressed to the point where I'm able to make working versions with their own PCB's. If I can pick it up, anyone can :D A DMM is good for showing you the OCV of the batteries, and if you can juggle it, the voltage under load, but a hydrometer will give you a better indication of the actual condition of a flooded battery.

A brief note about electric motors (I apologise in advance if you already know this), their torque curve is very different to an ICE. As motor rpm approaches peak, torque approaches 0. So, the faster they rev, the less torque they have, though obviously there's a sweet spot between rpm and torque. While we're talking torque, current is roughly proportional to torque, and voltage is roughly proportional to rpm. So more amps = more torque and more volts = more rpm. The tradeoff is that too much current = excess heat and too many volts (above the rating in a brushed motor) = accelerated brush wear and arcing on the commutator. In extreme cases overspeed will cause the rotor to come apart which is why you must never run a series wound motor at it's rated voltage with no load. Again, there's always a sweet spot.

I generally treat the ratings as a rough guide :D If you go too far over them, some forced air cooling via a fan to cool the windings is a good idea. Electric motors are rated at their continuous power output anyway, peak output is normally at least twice the continuous. I guess what I'm trying to say is find out how much current your controller is rated to deliver, use some Ohms Law[1] to figure out how many Watts you're delivering to the motor. Voltage sag under load will effect things significantly, but it give you a starting point to play around with anyway.

You might want to consider an ammeter and shunt (I got mine from
https://www.evparts.com but maybe you can get one from another forklift or something). You could use a friend holding a DMM plus the ammeter readings to get an idea of voltage sag under load, and also how much current your batteries can actually deliver to the controller.

Gerrys evconvert.com site is what brought project forkenswift to my attention. I've been hooked ever since :) I'd love to do a car, but not gonna happen in the foreseeable future (getting a modified car registered here is nothing that bulk $$ can't fix :mad: )

BTW, I just watched your video (forgot to yesterday). I loved it! There's nothing so sweet as the sound (or lack of it) of an EV cruising down the street. I especially loved the EV1 rip off at the end, classic :D

Cheers,
Ash


[1] i = v/r where i = current in amps, v = volts and r = resistance (watts)
https://en.wikipedia.org/wiki/Ohm's_law

You can shuffle things around like in any equation and I prefer to think of it this way: Watts = Volts * Amps. So if your "ESS" is 36V and it's delivering 100A to the motor; Watts = 36 * 100 = 3600W (incorrectly assuming no voltage sag under load).

Good tip, thanks. The book I've been reading "Build Your Own EV" (appropriate to crack it open, now that we're half finished, eh?) sort of pooh-poohs hydrometer use in favour of a DMM, which I took at face value. But I realize in retrospect, they're expecting you to be using a nice set of shiny new batteries.

No apology needed. Good refresher.

Got one! eBay, NOS. 50 mv shunt with a 600A scale gauge.

Yes - as much as it's useful (and fun!) to drive the car around and do DMM readings immediately afterwards, a proper load test is the way to go.

Yes, I've read that about both Australia and NZ. What's up with you folks down there? And all the trouble that the little REVA EV stirred up? Wow.

Cool - you're the first one who recognized it! :thumbup: (Or at least said so.)

Toecutter: thanks for posting that reply to the speed/performance question in the comments under the Youtube video

I tried 4 different times to reply to that person, but YouTube kept eating my response. It accepted it, said it was posted, but it never appeared on the page. Sometimes YouTube bites.

Also - good to see you get the point in about 130 mph. ;) Got to counter the myth / perception (that I'm contributing to) that EV's are slow and boring!

Guess what I bought today :)

Weld me a dream?

Had you ever thought of using motorcycle batteries?

Mcycle batteries? To power the car?

Yessir.

No, hadn't really thought of that. Probably would be difficult because their terminals aren't beefy enough to take the amps we'd be asking from them. Packaging would be easier though...

How many amps would that be?

Well, the golf cart controller is rated for 225A for 5 minutes @ 36/48v. Then it steps down in increments of 50A I think (it's all heat related).

The forklift controller will handle 400-ish continuous.

Hmm, well then. Not quite enough. I remember jared telling me the lawn mower battery he had in his civic was rated for 225~ amps and cost 20~ dollars, besides being light and small.

I'm trying to learn things, since I want to do this to the rex one day. One day...

How much are you asking for that torque monster?

I'm going to have it "remotely" evaluated by motor guru

Its the weekend! Time for some work, *whipsdarin*

I'd be especially interested in it if I could get at least 100 HP peak from it.

I'd be especially interested in it if it came installed;)

Sorry, "some assembly required". :)

What else can you tell us about it (voltage, V-max, amps, shaft type/size, etc.) ? Even the etc.? ;)

If the motor isn't marked, do you know what the original system voltage was?

he forklift was a 36/48v

ell, that wasn't too hard. Got the monster in the garage and took it apart. With 4 major chunks - 2 end caps, the body, and the rotor - shipping may not be impossible after all. Just do it with separate parcels.

Ivan's visiting his out-laws today, and he has a better camera than the antique 1 MP unit I've got. So the quality pics will have to wait until he's back.

Fun with ammeters - making a load tester
 

Played a little this evening with the ammeter.

Yikes
 

Man be careful -- don't end up MetroToast!

Darins gone mad! La la la.

I've been talking you up to people around campus, how famous you've become. If you want to visit and speak I can get you 3000 bucks for speakers budget...

I read just recently there's a Dartmouth prof who has a solar-powered EV (panels on the roof of his barn). Of course I can't find the reference now...

If you do tell me the name...might be jim merkel? I know a few have grease machines.

I don't think there was a name - just "a Dartmouth professor". Sorry.

---

Some drive motor pics:

It's our ADR (Australian Design Rules). They're very strict and rigidly enforced. Like everything, it's nothing money (and lots of it) can't fix, but it makes it a real PITA to get new kinds of vehicles on the road. When they do get on the road, they often end up costing a lot more than they probably should to cover the cost of DOTARS approval.

I'm a massive EV1 junkie. I was amazed when I found out about it, then even more amazed when I found out it was all done 10 years ago. Gets me pretty cranky when I think about the advances in EV's that could have been made in 10 years worth of development if GM hadn't killed it off. Ah well, if you want something done right, you gotta do it yourself! Looking forward to more updates as they become available :D

What's even more amazing (to me) is the EV1's were still on the road just a few short years ago. "The last private EV1 lease expired in August of 2004".

---

Mad props to you, darin. I'm serious, come speak here, we'll pay you...

Hoo ha! Someone with a Xebra beat me to it:

https://sjl-static2.sjl.youtube.com/vi/TertK0dKkjU/2.jpg

https://www.youtube.com/watch?v=iZpwnfzQKwc&NR=1

Awesome.

Great thread
 

It was fate I tell you! It was meant to be.

For a couple years I have been enthused about converting a Metro to either pure electric or hybrid (Mother Earth News like). Then last July my wife made the mistake of leaving me at home alone for a few days to go on a cluck-cluck trip with her girfriends. And an ebay auction for a '93 Geo Metro (with a bad engine) was closing while she was gone!

I mean that can't be a coincidence can it? I didn't have a choice did I?

But, sadly, it has been sitting out back ever since, cause I'm building a house. Then you come along and do exactly what I'd love to be doing, the same way I'd do it too - on the cheap, but worst of all with a Metro that looks exactly like mine! And it works!

Thanks a lot!:) Now what am I going to do? Finish the house or start piddling with the Metro?

Seriously, great work and great scrounging. Best of luck. I'll be checking the thread probably twice a day.