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Discussion Starter · #1 · (Edited)
Hi folks,

I would like to introduce myself and my project to the people on this fantastic forum. Converting a car to electric will be quite a challenge for me. I do have some experience working on cars, but I'm not a trained mechanic or engineer. I do have a cutting disk, welder, donor car, and a lot of enthusiasm for a EV conversion, though :)

My goal for this conversion is being able to reach highway speeds (i.e, 100 km/h / 62 mph, this would take the original gas engine 5500-6000 RPM), get a range of 40-50 miles, and keeping the clutch and stock gearbox. I would prefer AC drive with regenerative braking. I am considering a 96v Lithium pack.

As a donor vehicle I wanted something cheap but decent, light weight, and easy to work on. I ended up with a 1987 Citroën Visa. An oldtimer (25 years+) was desired to get in on the road legally here in Belgium (it needs an MOT once with gas-engine, and then never again).

The car cost me 350 euro (500$), and has done 107000km/ 66.5k m. It has the same engine as a Citroën 2cv (652cc, 35 HP), a 4-speed manual gearbox, curb weight is 755kg (1664 lbs), max gross weight is 1090 kg (2400lbs). It has no power steering, power brakes, AC, etc., which should simplify the conversion.







After reading a lot about EV conversions, and EV owners' experiences, I have decided not to go with lead-acid. But, LiFePo4 cells are expensive (much like lead-acid on the long run). After countless hours of searching for somewhat affordable prices, I stumbled upon the Chevy Volt pack-thread on this forum. So I went for what I love most; recycling stuff from scrapyards. After some expensive-ish offers, I came across a battery pack that had 35000km (22k miles) on it for 1250 euro (1700$).




I cautiously disassembled it into 7 pcs. of 48v (2Kw) and 2 pcs. of 24v (1Kw), and made 4 pcs. of 96v (180Ah) out of them.



I figured that should give me some decent range on a budget (I hope I am right). The two contactors in the pack came as a nice present.

So, I have committed myself to an EV conversion, but I am left with some difficult decisions to make, and especially about the type of motor+ controller and a suitable charger. It would be very nice of some of the more experienced members of this forum could give some some thoughts about these upcoming choices.

I prefer an AC motor+controller for the extra braking power (and the joy of loading the pack while coasting).

The AC-35 comes to mind, but with controller it comes at 3500$ + shipping (350$?). And I wonder, will it be powerful enough? And if it will...

I am also considering the AC-31/AC-45 motor that is offered on some forums and on ebay. I know lots has been written about it, but nonetheless (if powerful enough) it could make a great little motor I hope.

As a third option, which has produced a lot of grinding noises from my (little) brain, a local add showed up, offering, as far as I can tell, a used forklift motor, with adapter to suit my gearbox, and two surplus gearboxes on top for 630 euro (850$)?
Here, the rated RPM would be 3100-3500 at 84v. I think this suggests I should go higher voltage, which means reconfiguring my volt pack, loosing some capacity, as there will be left-over modules.
Also, no regen braking.
Also, wearing brushes.
Also, clutchless coupling?







Here I will be ending this post for now. I really can't decide, and I hope that the experience on the forum might help me to sort things out.
What motor would you go with?
Would you go with 96v?
Are there any obvious mistakes I am making here?

Thank you for reading


 

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Nice Project.
The DC motor must be tempting as it has an adapter plate and is cheap.
You should only do the DC motor if you budget is very restricted and you can save up and build an AC35 or 45 motor in the back ground and convert to AC/regen later while driving around on the DC.
In any case keep the clutch and don't worry about any particular motor not being powerful enough as the gearbox will allow you to use a small motor. That gearbox doesn't look to strong anyway so even an AC35 will do. Carefull with Sevcons as they have very expensive config screens.
You did well on the Volt pack but you wont need the water cooling plumbing and spacer plates. See if you can extract the cells and make a lighter smaller box to save weight.
 

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Interesting car you've got there, nice and light weight, should make a good EV.

You'll get a lot of feedback on the AC vs DC thing!

Personally I have to disagree with Rippertons negative comments regarding DC motors, they still represent excellent value in the power you get for your money. You can't have regen with DC, but unless you live in a very hilly area, regen is very overrated. A few years ago on EVTV, Jack tested an AC system with regen vs no regen over several extended runs and found absolutely no benefit to it, in fact I think his range was slightly reduced with it cranked up! This was before he started flogging AC systems though... ;)

If you do go DC, 120v to 144v would be better with your motor advanced 10 degrees or so. The motor shown may be a little small, I see it only weighs 48Kg, what's the diameter?

Whichever route you decide, I'll look forward to following your build :)
 

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Discussion Starter · #4 ·
Thanks a lot for the input. I appreciate it a lot.
It's nice to hear that the AC-35 would be suitable. I'll consider that as a viable option.
The cheaper DC alternative is certainly tempting.
But it is not really what I want to achieve on the long run I guess. Expense-wise, it would be an option to do the conversion with the cheaper second-hand motor/adapter. If this runs fine, I can upgrade. BUT, buying a 'testing only' DC controller might be a waste of money maybe...

My expense situation is to keep it as cheapish as possible, but since I got some good batteries cheap, there is some money left to spend on a more durable motor/controller combination. hard to decide...
 

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Discussion Starter · #6 · (Edited)
The motor shown may be a little small, I see it only weighs 48Kg, what's the diameter?
To be honest, I don't know. I haven't bought it (yet). It's only an hour drive to get it, so it is tempting. I can only guess from the pictures (knowing the size of the clutch) the diameter is about 8''. I do fear it wouldn't meet my end goal though.
 

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EVisa,

You mentioned this:
"An oldtimer (25 years+) was desired to get in on the road legally here in Belgium (it needs an MOT once with gas-engine, and then never again)."

I don't know the law in Belgium, but I can imagine it will be the same in most of the EU. Once you do this modification on an oldtimer, it's no longer an oldtimer (you will loose the status) and therefore it needs to be properly registered as a modification. I recommend you to check the regulations to be safe. Otherwise you might be in big trouble when accident happens.
 

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Discussion Starter · #9 ·
EVisa,

You mentioned this:
"An oldtimer (25 years+) was desired to get in on the road legally here in Belgium (it needs an MOT once with gas-engine, and then never again)."

I don't know the law in Belgium, but I can imagine it will be the same in most of the EU. Once you do this modification on an oldtimer, it's no longer an oldtimer (you will loose the status) and therefore it needs to be properly registered as a modification. I recommend you to check the regulations to be safe. Otherwise you might be in big trouble when accident happens.
I'm pretty sure it will still be an oldtimer. But you are correct that I should inform myself a bit better just to be absolutely sure.

I guess the issue is, can you swap engines on an oldtimer without renewing the MOT (required technical check-up), and especially if the new motor would turn-out to be more powerful than the stock engine.

I'll go after it!
 

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just want to say
my car has almost the same weight and original engine specs and i have a 6.7inch motor

i think u would be perfectly fine with that motor

with standard gearbox ur top speed is gonna be about 80kph with 96v though in a dc setup
 

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Discussion Starter · #11 · (Edited)
First of all, many thanks to everyone for the advice on my project so far. It has been a little quiet from my end for some time, but now it is time for a next step.

My Chevy Volt pack has been sitting here now for a while, and I’m looking for a charger to top it up. My pack is configured as 4x 96v. That is, 4 packs of 24s3p in parallel.

I am assuming my pack totals 180 Ah (12x15Ah), and minimum voltage per cell is 3V, maximum voltage per cell is 4.2V. So I guess I need a charger that give a 100V output. I came across the following 500$ charger.
http://www.batteryspace.com/Smart-C...t-off-for-72V-84V-SLA-70.3V-92.5V-Li-Ion.aspx
At 16A, it should charge my pack in 16.8 hours. (1.5x 180Ah)/ 16A.

To me as a novice this charger appears to meet my needs just fine at a reasonable price. Is there something obvious I am overlooking here? Or any other suggestions for a nice and affordable charger?


 

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Hi Evisa,

I too like your crazy, cool steering wheel! :D

Now let me save you some grief, do not buy that charger!

Firstly, despite what is says at the top of that website, it is not made in USA at all, it's Chinese, not that it matters, but it can be had for $320 here:

http://www.evassemble.com/index.php?main_page=product_info&cPath=3&products_id=11

Also, the import tax will be the same for you in Belgium weather you import from US or China.

But... much more importantly, you don't want it anywhere near your nice lithium battery!!!

I researched this type of charger a lot when looking for one for my car, I don't think it's power factor corrected to start with (which makes me dubious of the CE listed claim!) so isn't allowed to be used on a European electricity grid. They're also under engineered and don't have adequate vibration or waterproofing for in car use. Just look at the two fans blowing air (and dust!) through the open, ended case!

The guys over on endless sphere have a thread on them, they are OK for charging bikes off board but still fail often!

I'd recommend the TCCH charger. Lots of people on here have used them, (including myself!). They've proved to be a good quality, value for money charger. I bought mine here for only $540, you can buy them elsewhere for more if you like! ;)

http://www.evassemble.com/index.php?main_page=product_info&cPath=3&products_id=23

Keep up the good work :)
 

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Discussion Starter · #13 · (Edited)
Thanks Favguy,

That is some useful info :). I knew I'd better ask the pro's before purchasing. Keeps my EV-budget alive ;)

However, the chargers you refer to use a fixed charging voltage. I believe my 96V volt pack will operate between 72V (completely empty) and 100.8V (completely charged). Thus, the battery pack's requirements are not consistent with the fixed charging voltages of typical chargers. This is something I keep bumping in to. And that's why I appreciated the variable output voltage of the charger I mentioned.


I guess I need a 100.8V charger to fully load the cells to 4.2V. A 72V (96V output) charger may do, but would load the cells only up to 4V, which means losing range (safe against overcharging though). A 88.8V (100.8V output) charger seems perfect, but they are pretty rare.

Though choice...
 

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Hi Evisa,

You misunderstand what is available with the TCCH chargers. The linked page shows an example list of voltages, but they can be ordered with any termination voltage you want, and you can specify up to 10 charge curves with them, giving you a range of end voltages :).

On your battery, I'd probably terminate at 4.15v per cell for safety, in any case there will be very little extra Ah's to be gained above this.

Regards,

Paul
 

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Discussion Starter · #15 · (Edited)
I am very happy to have misunderstood that :). This means I am no longer worrying about finding a suitable charger for my Volt pack. Your comment made me a very happy man.

Just have to decide on ordering either the 2500W or 3000W version.
 

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Discussion Starter · #16 · (Edited)
I've emailed them asking for the specifics they'd need from my end to set up a 3000W charger to meet the needs of my volt/ampera battery pack.

Thank you so much.

In the mean time, I'm off cleaning up my garage to make some space....:D

 

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Discussion Starter · #17 ·
So, my garage got cleaned up, and the Elcon 3kW has been ordered.

So I decided to start working on the rear battery box that should accommodate two of my four 96V Volt packs.

First got rid of the fuel tank and rear part of the exhaust. It’s a nice feeling knowing I won’t need them anymore


I decided to use the base of the original Volt pack to bolt the battery packs on to. This should hold them in place securely. I got rid of some of the edges to save space.


I used some pretty heavy iron L-shaped bars, and started to construct the bottom of the rear box.


This is what it looks like when things started to take shape. Pretty heavy unfortunately, but at least it should be strong…


I used filler to make the battery box waterproof,


After priming and painting, almost done riveting the sides.




I still have to drill the holes for the cables, and make a strong but not too heavy lid. .
Also I have to decide whether to keep the liquid cooling or not.


.
 

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Hello EVisa
May I ask where you bought your battery pack from please and how you found places selling them. I am struggling in the UK. Thanks
 

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First, words of encouragement- you have done the hardest part already, securing a battery for a good price. My own cost me over 4 times as much for not very much more capacity- you are very lucky!

So I encourage you to spend a little of that savings on an AC system. Buy from HPEVS- be careful with e-bay as there are plenty of warnings here of people who were sold bad stuff. Keep the gearbox and clutch. You will have perhaps a less dramatic acceleration machine when you are done, but also less maintenance and hopefully a longer lasting solution, efficient and with the small but real benefit of regenerative braking- reducing wear and tear on your brakes as well as increasing range a bit.

A 3000w charger will charge your pack very quickly. You could have made do with less as your pack is only about 16.5 kWh in real capacity, but more is definitely ok.

Don't know if you need heating or cooling for you pack and climate, but if winter driving is in your plans then heating and insulation and hence also cooling will be required.

Looking great so far- fortunately you are starting with a car in better condition than mine, which would be hard to avoid in my case because mine was so terribly rusty. I am still doing body filler and sanding and cursing my fate...
 

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Discussion Starter · #20 · (Edited)
Hello EVisa
May I ask where you bought your battery pack from please and how you found places selling them. I am struggling in the UK. Thanks
Dear Tylerwatts,

I came across my pack by looking online for scrapyards, and by calling random scrapyards. Here, they have sites where you post the part you are looking for. These sites will forward your request to dozens of scrapyards.

Two offers came in. One for 3000 euro. I looked up the scrapyard, and found a picture from the donor car. It had been in a fire. The right-rear tyre had even melted, so it would have been a gamble not worth taking.

Another offer came in at 1500 euro. I called them, but when asking for details about the car, they would call me back, which they didn't.

I came across this very pack by googling random scapyards, and one of them just happened to have a very documented site (with pictures), and had an Ampera/Volt pack. I mailed them for a price, they replied 1250, I said, I'll snap that one, I'll pick it up tomorrow morning. A six hour drive later it was sitting in my garage :)

Keep looking, call them, don't bother to ask them. For me, they all answered me very politely, even when they didn't have any in stock.
 
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