Hi From Melbourne, Australia (looking to build EV runabout on a student budget)
 

My name is Tom, I'm on here because I purchased a host vehicle today for an EV conversion. I found a heap of inspiration on here for building an EV after coming up with the idea recently. I talked a lot with like-minded friends and have something of a team assembled to help with this one, and then hopefully convert their own vehicles. The first step was finding a host/donor vehicle (is there a preferred term for this?), and now to strip it of all the ICE parts and start sourcing parts.

The plan is:

Electric runabout car for less than $1000AUD (not sure if it's been done in Australia yet, I have read a lot about 'Forkenswift' and similar budget conversions). We're going with the tagline 'Electric car on a student budget' which is exactly what it is. I am primarily doing this because I want to have a car. After going without for several years, mostly for enviro reasons, I decided the best option was an electric runabout. We're aiming to use recycled parts where possible.

Host vehicle (1981 Daihatsu 'Handivan')
DC series wound motor from a forklift
Any batteries we can find without paying (much)
DIY controller

To be practical for regular use in my case, the car should be capable of travelling at 70km per hour, and have a range of 60km. I calculated this based on a round trip (and the highest speed limit on the way) to my girlfriend's house :cool:

The car ($200, plus $100 for a tow to get it to my house) will need a little panel beating and rust removal, which I believe I am capable of. Otherwise, it is a perfect host vehicle. It is small and light (570kg curb weight with ICE), and has a decent amount of space behind it for batteries. A friend has promised to mount the motor and machine an adapter plate for a case of beer, we're going to hold him to it.

At this early stage it looks like the most expensive part of the conversion will be registration ($700), a road-worthy certificate and engineer's certificate if necessary. These costs mean the project has already exceeded the budget, but we'll see what we can do to get around them.

I am setting up a blog to document the conversion, I'll put details on here ASAP.

Ambitious project!

"Host vehicle" works.

A 60 km range is going to be another challenge - unless of course you have a source for "cheap" lithium! The ForkenSwift gets 20-30 km on ~520 lbs of used golf cart batteries (~10kWh worth). Might get 50-60 on brand new ones. And that exceeds our far more modest design target of 12 km minimum (distance from my buddy's place to his work). No girlfriends in the next town! :D

Well we have been planning on trying to get organisations to donate in exchange for sponsorship of the vehicle. If we get good publicity for the car once it's complete a battery distributor might get some business from us recommending them or mentioning them on our blog.

Just an idea...

In any case, happy to aim higher and settle for less. Have you heard of any similar budget conversions in Australia?

Tom

Also, is the range the only ambitious aspect of the project in your eyes?

Cheers

Edit: Aaand, what was the curb weight of the forkenswift before conversion?

The car went from ~1750 lbs stock to ~2070 post-conversion, roughly.

Yeah, I would say the batteries are going to be the biggest challenge. Cheap, decent motors & other componentns are available to the patient & resourceful, and a DIY controller keeps costs down in that department.

Eventually it will be possible to find used lithium, since more and more people are putting them in conversions now. But we'll likely never upgrade the ForkenSwift, since 20-30 km on used lead is gravy. For use in a small city, it's already literally more range than is needed.

(PS - hope you don't mind I moved the thread to the Fossil Fuel Free section - probably get more feedback there.)

Thanks for the info, and yes this section makes more sense. I've revised the performance target to 'whatever we can get' in light of your information!

I have found an electric motor, picking it up this week.

I'm told it's a Nissan 48V 3.9kw 96A (does this mean amps? I'm not so good with these numbers yet...)

Does this sound suitable? It's from an old elctric forklift, already removed and I've been quoted $100... Sweet.

Any idea how much it weighs/dimensions? That's often a good indicator of how suitable it is too.

Not sure as yet, have to go see it, they seem bemused that I want to buy it at all so not bothering them with too many questions.

Regarding size, is it just whether it will fit in the engine bay or not? If it fits in the tiny engine bay then I think weight won't be too much of an issue.

As a really loosey-goosey rule of thumb, a bigger & heavier motor might be able to take more abuse and may be less prone to heating up than a smaller/lighter one of the same type & power rating.

The motor in the ForkenSwift was rated for 36/48v (no power specs though) and weighs ~110 lbs. A motor expert told us it would easily handle 120 volts.

A little cold calling, a trip out to the 'burbs and $100 later, I got a motor!
http://farm9.staticflickr.com/8287/7...5488bfcfe5.jpg
photo by thmnstrtexl, on Flickr
http://farm9.staticflickr.com/8435/7...34f03e3481.jpg
photo (1) by thmnstrtexl, on Flickr
6.5 in diameter, 12 in length.

My friend and I were looking at it yesterday wondering whether it was too small? But as a 48V motor it should be fine, right? Remembering it only has to move 500-700kg of weight (I think this is something like 1100-1500lb?)

Anyway, a big step forward for us. I'm told it needs some reconditioning so if anyone has any good resources on how to do this then send them my way!

I'll start a build thread soon with all the details, as well as the blog.

Cheers Metrompg for your help so far!

Tom

Also, there's an identical motor at the forklift place, so if I have success with this one I'll go pick it up. Its small size makes me think it could work for an electric motorcycle as well...

Edit: If the photos don't work: the specs written on the side are:

TTL160C
48V S2 60min
98 A
1920 min-1 max: 1000 min-1
(the 'max' figure might have another 0 after the 1000, hard to tell as there's a scraped off part of the label)
Class H

Code: 2319713

Sounds like it should work quite well.

Yup, should be fine for your modest needs. Congrats!

Service ... usually means new brushes and possibly commutator resurfacing. Maybe bearings. Take it apart, clean it up and have a look. :)

Yet to take apart the motor but we had a successful day removing the fuel tank and the rest of the ICE. Two cylinder motors make it easier because you can lift them out with a couple of people.

Here's the link to our blog and first vid. Mentioned ecomodder at the end

Electric Car on a Student Budget

http://www.youtube.com/watch?v=ACQw9Mp3vGs

Too funny! (PS - if you want, you can embed your YouTube video in the forum just by posting the link in the text of your post.)

If you guys scrounge and are as resourceful as it appears you're trying to be, you'll be able to do this for your budget goal. Don't think you'll get that 50km range though, unless you buy new batts. (Repeating myself... getting old, apparently.)

We ended up spending about $1k total (Canadian dollars) after selling all the bits & pieces we could. Though, yes, it was registered and being driven at the ~$700 mark (net).

Batteries: I don't know if there's an EV club in Melbourne, but we have been running used 6v golf cart batteries - "hand-me-downs" - from other EV owners. At first we tried using returns from commercial floor cleaners from a local company that services them, but then we ended up getting used batteries from EV owners and that worked out much better (similar capacity/condition).

The good thing about other people who build cars that NEED, say, 40-60 km range is that once their batteries can no longer deliver that range, they are deemed worn out and they have to replace the pack. Meaning: we're lucky to have been able to buy batteries at not much more than scrap rates that are effectively only ~40-60% worn out, and still good for 20-40 km range in the ForkenSwift)

Another bit of semi-related advice:

Make a dedicated web site for your project that you can put Google ads (and ads from other companies) on. (Not sure if you can do that on blogspot.) If you see this through to completion, document it well, and get the word out online about your project, you can make a bit of money each month from your site. In fact, over ~4 years, Electric car conversion on a beer budget - ForkenSwift.com has made back in ad revenue the entire out-of-pocket cost of the project. So it's effectively a free car. You heard it here first. :)

Tom,

Interesting project! I remember struggling a bit to find suppliers in Melbourne a few years back (I'm in the UK now and there's a bit of a bigger scene here for it). I'll see what I can dig up though if you still need info. Spent many hours trawling the forums!

Ed

Hi Guys

We've been super slack with the project since the engine came out. We're trying to sort out the adapter plate and mountings at the moment, as well as still searching for batteries. We think if nothing else we can buy four new 12v batts and won't go over budget too much, but i'd really like to keep as much of the parts reused/recycled as possible. We were offered an old prius battery as a donation but it looked a bit too much trouble with the controller and charging, as well as keeping under budget. Tell me if I'm wrong...

@MetroMPG: Thanks for the tip on the EV club... We've started searching websites and phone numbers, I'm almost certain we'll be able to find some that way, if not just finding a supplier. Everyone we found so far has been interstate, and freighting is an issue with batteries apparently - the cost and finding someone to actually do it.

Also thanks for the tip on the site! I know you can put ads on blogspot as it's a google product, we are looking at linking the site to a specific domain name so it seems a bit more pro but if we can't then we'll definitely build a new site. Blogspot is just so easy! Won't get ahead of ourselves too much but making back a bit of the money would be nice!

@Ed:Yeah any help with batteries is appreciated! Were you affiliated with any clubs when you were in Melbourne? I can imagine the scene would be bigger in the UK where distances are so much shorter. How did you go registering your car and getting an engineering cert? Seems to us to be the most expensive thing we'll have to deal with!

Cheers again for the help and we'll get the next vid up soon...

Tom

What about checking with a large truck service center? Big rigs have large format 12v batteries, especially the long haul trucks with sleeping quarters, often mulitple batteries per truck. I was going to take that route before landing the used batteries from another EV owner.

FYI, this "runabout" EV used four 12v batteries: EV Weblog: Yugo Greg! . It's a similar project.

You're not wrong. Also, Prius battery only has about ~1 kWh capacity (when new). Good for about 3 km range! :)

Good idea on the truck service centre, there's actually one right around the corner from my house.

Yeah that's a similar project except that bloke seemed to have more tools and machining experience. I'm handy with tools but I've never worked with metal.

Every time I think this project is going to fail I come across something that makes it seem entirely possible, if not easy. Which is great, and I can't wait to have it finished.

Can anyone tell based on the specs of my motor, remembering that it's from a forklift, whether it's dc wound series or not? I've had an offer for an Alltrax AXE 4845 24-48v controller that I think will be great for at least the first phase of the build - getting it on the road. I think this will only work with a series wound motor but I could be wrong. The motor is still sitting in the shed untouched, I'm going to take it apart and have a look, and hopefully test it after a cleanup. I will post photos on here if what I'm seeing doesn't make any sense...

Hi all, just a quick update:

Found out the motor is series wound, and is worth $1300 refurbished (we got ours for $100)

RE: batteries and budget

We found free batteries. Maybe. A guy (legend) in Perth has several hundred nicd 1.2V 40ah cells to give away - from an old aviation company, barely used. This is great because they have an incredibly long service life and are quite difficult to ruin. Apparently. But they're free which is great. We just have to pay a couple hundred in shipping, bringing our total spend to $600 and leaving $400 for the rest of the build.

We're looking at running a higher voltage now, a 72V or 96V should get us the range we need, or two 72v packs in parallel. my best estimates for a 72V 40aho pack are between 20-30km range.

But I shouldn't count my chickens before they hatch.

Anyway, progress being made and coming in under budget is far more likely with this development. Sweet. :)

That's great news all around.

I knew the same guy (surplus airplane NiCd cells)! But my guy was for real and lives in Ottawa. :D I declined taking those cells off his hands only because I had a line on "known condition" used golf cart batteries.

Keep us posted!

OK so a new development, the same guy that offered the free nicd cells has a contact with free nimh cells here in Melbourne, so I wouldn't even have to pay shipping.

As they are sealed and come in plastic cases rated to hold the mass of the batteries, we only need to bolt them in. This also means they can fit neatly in the back seat area with no vented box needed.

There are some which will have to be thrown out, and I'll have to test ALL of them for capacity before using them, which will be a real mission, but again they're free. So I'm happy to put in the work to keep to our budget.

Usable capacity is around 20ah, maybe more, which I've estimated will get us around 15 miles/25km range and get me to work and back. If not, there are enough cells to add another set in parallel later on (I haven't yet worked out if this is a good idea or not).

Also, I got an offer for 7 sealed lead acids with around 90% capacity left that may or may not be good enough. Ideally this would be a back up option to run a 72v pack if the nickel offers fall through. They are only $20 each. Had I got this offer a month or two ago I would have taken it straight away but I'm willing to see through the nimh's for the extra speed and range we could get.

Other things, looking at running an accessory battery under the bonnet to even out the weight of the batteries in the back (the individual cells are too tall to fit in the engine bay), and rather than using a dc-dc converter.

Also purchased a second hand inertia switch ($13) for emergency cutoff in case of a crash - My first purchase since I got the motor.

I suggest that instead of two parallel packs, go with parallel pairs of batteries with the pairs in series. Much easier to keep track of voltages and much easier to keep balanced. See my build or blog in my signature and check out my wiring diagram.

Thanks for the tip mechman. That's a great blog you have there!

I have just updated our blog with some info and a (6 month old) video of us pulling the ICE components out. See my signature for the blog link.

FYI I looked at buying the raider charger on ebay after looking at your blog and the postage to Australia makes it $60!!! Oh to be building this EV in North America!

For what it's worth, I think the Raider is easily worth $60+. It works ridiculously well - better than some $100+ chargers I've used.

And thanks for the kind words!

We got the (free) batteries!

Two 125V packs of nimh cells, 20ah. We are planning on removing the dead cells and consolidating the best ones into one good pack.

Should get us our range of 25km IF we keep our host vehicle.

I was looking the other day at the panel work that will need to be done (some rust, dents on both sides, some in tricky places) and wondering if we will blow our budget on body work alone! The car has been against a fence for a while - the bad side not really visible. Also, the key that came with the car doesn't open anything... ****! Why didn't I check all of this?

So I'm in limbo, get a new vehicle? Or fix this one? As we've planned on our range goal of 25km being achieved in this car (600kg, 1250lb) if we get anything else it will be heavier and won't go as far!

Any advice at this point is welcome.

But the good news is, like I mentioned, we have plenty of batteries, possible lines for more if we do end up with a heavier car.

Bitter sweet stuff!

Congrats on the batteries!

Is the car body really that bad? I've only seen one side of it in the video, and it looked fine to me. Dents & surface rust (assuming it's surface rust) ... is it really an issue?

Yeah I'm still deciding whether it is or not. It has made me kind of more motivated to get it done, save scrapping the car and adhere to the environmental principles that made me want to do the project in the first place!

I had a look and I can't find a single car with as low a curb weight as our current vehicle.

There is some proper rust in the fuel inlet area, but I have to remove this anyway. Also, on the inside of the rear hatch - not a structural area, and I think I can get rid of most of it and putty it up.

Other than that just dents one one side, I have been looking for a replacement door, which would save a load of trouble!

Nice boat tail by the way! I need to spend more time on the forum!

Subscribed, I'm keen to see how you travel through and get it through to registered and on the road.

What is the typical characteristics of NiMH batteries as far as charging VPC, low and high VPC cutoffs, etc? I guess they do not require fancy BMS like lithiums and are much harder to murder, which makes it great for a starter pack.

Hi guys,

Sorry but notifications from ecomodder ended up in my spam folder somehow!

NiMh like being discharged, so having them sit for a long time isn't an issue (individual cells at 0.5V). They don't like high temperatures which might be an issue in summer for me, temperatures above 40 Celsius, so need fan cooling when driving. I have a set of fans I can pick up from one of the guys that gave me the cells, but might need to make up some more to be sure.

I'm a bit of an electronics noob, what is VPC?

I ordered a hobby charger so I can charge small strings and work out the usable capacity of the cells. Unfortunately the plug that came with it was broken so that will set me back a while. Basically I have to charge, discharge, charge, discharge again to get an amp hour count and work out which cells won't be suitable. Some are obviously dead as they physically bulge, so they're easy to spot and remove.

After the initial test I imagine I'll have to check cells every few months or so.

The pack voltage should indicate when enough cells are failing.

VPC = Volts Per Cell.

From what a Google search tells me, NiMH batteries are nominal 1.2VPC.
To contrast, a typical lead acid battery is around 2.1VPC (X 6 = 12.6V).

Gotcha, Yes you are spot on, they're 1.2 volts per cell. I have about 200 of them to test...