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Build your own Electric Car!

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The "Electro-Metro" Project.

Can't afford a Nissan Leaf? No Problem!

Build a cheap electric car yourself by removing the the car engine, replacing it with a forklift motor, and adding batteries.

I have plenty of videos about this project at:
http://www.youtube.com/user/BenjaminNelson
and 300MPG.org

The primary "build blog" for this project is at:
http://ecomodder.com/forum/showthread.php/ben-nelsons-electro-metro-build-thread-848.html
but watch out! That is a good read for when you have WAY too much time on your hands.

For a good intro to basic electric car construction, stick with this Instructable.

For more in-depth construction information, check out the instructional Video DVD available at 300MPG.org

 
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Step 1: Get a car.

Picture of Get a car.
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The first thing you need to do is get a car. They are not all equal.

I was looking for something lightweight, with no power anything.

Heavier cars need more energy to push down the road, thus limiting your range on batteries.

Things like power steering and power brakes run off the engine, which is going to be removed anyways, rendering them useless. Power windows and locks add weight and complexity to the vehicle.

I ended up finding a Geo Metro for sale, for $500. The engine ran fine, and the body wasn't too bad, but I couldn't drive it home because the clutch was messed up. Oh well, this conversion isn't going to use a clutch anyways!

Make sure the car doesn't have anything major wrong with it (other than maybe a blown engine!) You want to do a Conversion, not a Restoration!

Many thanks to you for this very useful blog.. But I wanted to ask something.. I have some of the old Toyota forklift parts with me so can I use it
in building an electric car?

Ken Myers24 days ago

Thanks for posting! However, I need more range, top speed. I was thinking of EV for commute to work, 40 miles each way. The commercial models (other than expensive Tesla) do not provide this, tap out at 60-70 miles, like Leaf. I also like the idea of DIY and recycling/repurposing old vehicle. I'd really love to take an older car with a nice body style (IMO) and modify it to EV. I'm not auto mechanic, would likely look to pay for the mod, assuming it can even be done, to make a vehicle that can 70mph, range 100+ miles. Some cars I thought might work for this mod include: (1) any classic car with bad or no engine, like ford mustang or Camaro, (2) the Ford Probe (93ish), Mazda MX6 (also 93ish), or Mazda RX7 (also 93ish). We'll I guess listing every car I would be willing to use would take to long. I really think with the state of the world, limited resources, and too much rubbish in landfills, that retrofitting older cars to run as EV is really an awesome idea that more mechanics should develop into a highly reliable (and reasonably priced) mod. Rather than spending $30k on a new EV, I could see buying a used "shell" car for $5k or less, and then paying a mechanic $10k to modify it to an EV, and it still is half the price and better for the planet. If anyone happens to read this and know if this sort of service is offered anywhere, let me know.

You might want to try adding the Hendershot Electrical Energy Device, You will need to turn the energy drawn into DC current tho.

what is your distance range on this? great instructable!

jjaan22 days ago

kindly explain this in breif so that i can explore ?

ajensen271 month ago
u think a ranger would make a good(not better) EV since i could load the bed with batteries(or under it) and since length of motor is not a big issue. only issue i see is the weight (and cost of all the extra batteries and the controller). also for speed control on an automatic would i use the torque converter and let it do its job?
bennelson (author)  ajensen271 month ago
Light trucks make GREAT EV conversions! Rangers and S10's are very popular. Follow this link, to see a bunch of home-built electric trucks. http://www.evalbum.com/type/TRCK

On an automatic transmission car, the torque converter does NOT control the speed of the vehicle, it takes the place of the clutch. You still need a motor speed controller.
tonyscott1 month ago

Great job, mate. is it legal, I mean can you drive on roads without been stopped by police? thanks for sharing.

bennelson (author)  tonyscott1 month ago

Yep, perfectly legal. I did get stopped once, but that was for speeding!

How does this car compare to an average every day car?
bennelson (author)  stuff and things1 month ago

It depends on what you mean by "average everyday car". The best I can do is compare it to the gasoline version of the same car, which had a 3-cylinder, 1-liter engine. It is MUCH quieter than the gas version. It doesn't go as FAR per fueling as the gas version. With gas, you fuel up about once per week, with electric, you just plug it in after you use it. It can go the same speed and have about the same acceleration as the gas version. Top speed on this car as electric so far has been 73 MGH. I have gotten a speeding ticket in this car. It uses about 1/4 as much energy as the gasoline version of the car. I run it on renewably sourced electricity. I shift less in this car than the gas version. I generally just leave it in third and use that like "DRIVE" on an automatic transmission. The electric motor has enough torque to use less gears and less shifting. The electric motor can't stall the way a gas engine dies. At a traffic light, instead of having to push in a clutch or take it out of gear, I simply let the motor stop spinning by taking my foot off the accelerator.

edenton13 months ago
Couldn't you hook up a alternator to help recharge the batteries
bennelson (author)  edenton13 months ago
What would you hook the alternator to?
the wheels. thr drive shaft. anything that spins. it may not be alot of power back into the batteries, but could help extend the life
Lukasas752 months ago

I also built my own electric car with my hands :) I was cheaper almost twice and I can even say- it succeeded even better :) I bought all of the parts online here- <a
href="https://www.pigiausiosdalys.lt/">Pigios
automobiliu dalys</a> and I havent even expected to get so high quality for such a low price :)

radeq3 months ago
Hello, super inspiration and my big dream for many years! BUT, what about technical licence? I don't know US laws, but all european police patrols strictly check the "papers" of a car and "conersion" like this is direct order of very big fine :-(.
If it's easy or free in the US, I'm quietly envying, but I'm afraid, nor there is it possible...
bennelson (author)  radeq3 months ago
No matter where you live, make sure to check your insurance, title, registration, and any other legalities you need to take care of before doing an unusual car project.

You want to make sure ahead of time that you can legally drive your vehicle when it is all finished. The only issue that I had on my car was that it was difficult to pass pollution controls! Yes, even without an engine, I still had to do a smog test!
radeq bennelson3 months ago
If I understand well, your car is really completely legal? May I ask what all did you need to do (and what to pay for it) for registration ability? We in Europe need for this action an army of lawyers connected to bribed officers and policemen.

Sumary: It's quite easy (and relative cheep) to physically convert, but quite impossible (and/or expensive) to legalize. So, finally nobody try it there (although there is gasoline more expensive than in the US!), because of legalization problems and/or fees :-(
bennelson (author)  radeq3 months ago
Yes, this car is completely legal.

It still has all the original safety features. This car has "daytime running lights", which have not been modified.

It has driver and passenger-side airbags, which have NOT been changed or modified.

The original seatbelts are all intact. Although I cut around the back seat, I make sure not to alter where the seatbelts mounted.

Before starting the project, I called my insurance company and told them exactly what I wanted to do. They had no problem continuing my insurance. Their thoughts were that the car had a lower top speed and would only be used closer to home would actually make it a BETTER insurance risk.

I already had a clean title for the car.

Registration in my area requires a pollution test. I wasn't able to pass it (even though the car doesn't make pollution at point of use) because without an engine, the ODBII system used at the emissions testing was not able to communicate with my car. It took me a while to find the correct government official for me to get an exemption, which required a mechanic to inspect the vehicle. That man looked under the hood, said "Yes, there is no engine in there", and signed a form.

The United States has a long tradition of people working on and modifying their own cars, so it tends to be pretty liberal on making changes, as long as they are still safe. That said, exact laws can vary quite a bit from State to State and even which County you are in.

For NEW cars, it is EXTREMELY difficult to begin a new car brand, and it is one of the most highly regulated industries in the U.S. (Thank you Tesla Motors for all the hard work you have done! shaking things up!)

BEFORE starting a project, make sure to check over what things will be required for you to legally drive your vehicle and that you meet all your requirements.
radeq bennelson3 months ago
Yes, it sounds very logical, safety should be only required for successful conversion legalization, but european laws aren't logical. As I said, I'm envying liberal laws (needed a pollution test is only a dry fly). In EU, mission impossible ;-).

P.S. In fact, no wonder, that EU make individual GAS-EL conversions so unpleasant. The hole EU stands on gasoline excise taxes. Better labor mobility is not interesting topic (to ban cheep traveling is much easier way to fill a budget). So, there'll may be a chance until it runs out of oil, ..., but then EU will certainly make double (or quadruple) electricity tax :-D
joe bloe3 months ago
hello, I've read about your experience with standard tranies, but not automatics. with the standard, your didn't include the pressure plate. as it relates to the auto, would the same apply concerning the torque converter? or, to ask to same question differently, would there still be torque in need of conversion? (regardless of motor type)
acunliffe14 months ago
Have you ever thought of adding a hydroelectric generator to charge the batteries on the go (and stationary). You could siphon the water back to the top so you get a unlimited amount of energy and it would run 24/7. I was thinking you could either use lots of smaller motors or one big one. Then maybe you could use a transformer to get it to the right voltage and charge them in series?
wrigd20095 months ago
Fast question! What is the size of your garage as it seems very crowded?

I have to build my garage next spring and would like to base my garage size to yours and add a few feet here and there.

Thanks,
Donald.
bennelson (author)  wrigd20095 months ago
It's a pretty stock two-car, detached garage. Nothing fancy. If I had bigger I would love it. I have no basement or other storage, so EVERYTHING goes in the garage.

The exterior dimensions are 22' wide by 20' deep on a concrete slab. typical 2x4 stud construction but only exterior siding on top of that - no sheathing, and no insulation. I can see daylight through some parts of the wall. Not the best place to work on cars in the winter!

The garage is more likely to look crowded because of all of what's inside of it, rather than its size. A single car garage looks spacious when there's nothing in it!
Thanks!
Donald
j416976 months ago
Do amps from the battery have to equal amps in the engine?
wrigd2009 j416975 months ago
Refer to the C-rate of your battery.

The C-Rate is the capacity rating of the current flow in the battery. Example, a battery with a 40A-h and a C rate of 3-C will give you 3 time 40A, which is120A however, be advice that you will not be able to run an electric motor for an hour as you are "sucking" a lot of juice from the battery.

Also, make sure that your inverter, motor controller, wire and electric motor can handle that much current.
Johnt0078716 months ago
Nice conversion! I have heard of just connecting a hair dryer to the A/C ducts to act as a heater for small cars. Might be smaller/easier than your radiator. Still running strong?
bennelson (author)  Johnt0078716 months ago
The only real issues I've ever had with the car was picking through my pile of used lead batteries.

The more in series, the more the chance of one of them not being as good as the rest and dragging them down.

That's really it though. Everything else has always really worked great. I'm taking a look at the possibility of upgrading to lithium next summer, depending on my budget. Lithium prices are always continuing to come down.
cool austin7 months ago
love this. lots of useful information. what im doing for my car build for the ac and heating, im going to use PVC tubing and thermoelectric coolers and solenoid valves. and add a bunch of computer fans. with this can have two tubes that go into the vehicle, from different sides of the thermoelectric cooler. (one side hot other side cold.) when i ask for cold a valve allows the cold side to blow cold air into the vehicle. and the hot side will have a fan blowing it away from the car. and vice versa if i wanted heat. of if you justr want heat you could use a 12v heater: http://img3.banggood.com/thumb/view/upload/2012/liangping/SKU0605641%20(2).jpg i hope to add a tutorial or something giving more detail to how i would do this. keep up the good work.
pmayo18 months ago
I have a suggestion for you heat issue if you haven't already figured it out. I came up with this idea when I read the coolant removal step. It's possible you coil imitate that function with oil like the heater you use to heat your car up. Possibly try to have the oil pumped passed a heated area or heat source and then through a coil of some sort and then blown by a fan. It's similar to how the coolant transfers lost energy into usable energy in the winter time.
Ben19828 months ago
Ah, of course. I didn't even think about it being front wheel drive. Love it.
Ben19828 months ago
I like what you've done with this conversion. To reduce weight and save power, couldn't the transmission be eliminated if a driveshaft ran from the motor to the rear differential?
bennelson (author)  Ben19828 months ago
This is a front-wheel-drive car, so there is no rear differential. The differential is built into the transmission in the front, which is as good of a reason as any to keep the transmission.

On rear-wheel drive cars, there are setups where builders will put a high-power, high-torque motor onto a short driveshaft and straight to the rear differential. Makes for sun little dragsters!
Wired_12369 months ago
Just a quick question. Would a AMC Pacer work or would that be to heavy?
bennelson (author)  Wired_12369 months ago
I would imagine it would work fine. With any older car, make sure the frame or unibody is in good shape, and also check to make sure parts are still available so you can keep the car fixed up and rolling!
msihcs2 years ago
First let me say I am extremely impressed that you would take the initiative to actually do this type of project I have dreamed of it but never actually took the leap.

My background is mechanical engineering (operating steam plants in the Navy) I do have a question though. My relatively average knowledge of electronics would lead me to think that as long as the motors are identical and the current to them is regulated properly that you could use 4 smaller motors (one at each wheel) instead of one big one to propel the vehicle. If run in parallel the motors should all turn at the same speed (I am sure a computer could further regulate the current to keep the wheels within a certain range of each other)

I ask this because the price of motors that are 25+ hp are a little high for the average person to purchase for their first EV project this (as BigTurd suggested) would also cut the need for a full sized transmission.
phase90 msihcs1 year ago
As Bennelson says, only two would be needed (not 4). There are additional issues with unsprung weight unless there are coupling shafts and the motors mounted on the frame. That would put a lot of stress on the suspension.
Second issue is synchronizing the two motors so they spin exactly the same speed (unless turning). If one spins faster (or slower) than the other, the car will pull to one side. Not fun. Dealing with tracking issues when turning due to a different turning radius on the wheels would be even harder. Better to drive a differential and let it do the work.
bennelson (author)  msihcs2 years ago
Yes, in theory, each of 4 motors would only have to do 1/4 the amount of work. I used the existing transmission in the car because the vehicle is already designed to run as front-wheel-drive. The transmission not only has the gearing, but it is also the differential and connects the "half-shafts" (sideways-traveling short drive-shafts) to the front wheels. The trouble with using four motors, one on each wheel, is that you will have to figure out where to mount each of those motors and how to connect it to each wheel.



In a brand-new, custom-built vehicle, it would be easy to design for. In fact, with the motors out of the way, and no traditional transmission, it would give you great design flexibility. Modern car manufacturers talk about that sort of thing all the time. But for a simple conversion of an existing car, just replacing the engine with an electric motor and adding batteries is far more straight-forward than designing/manufacturing/fabricating everything for multiple motors and driven wheels.



I think that a four-wheel-drive hub-motor vehicle would be a great project to see. It might start off best as an "off-road-only" vehicle, something like a dune-buggy, ATV or something similar.



The "Tropica" electric car, designed by Bob Beaumont, also the inventor of the Citicar, was rear-wheel drive with TWO electric motors. Each motor was mounted on the swing-arm of the wheel, along with a belt and pulley to get the gear ratio right from the motor to the wheel. Also, each of the two motors had its own controller.

As for the cost of motors. There are plenty of good ones that can be bought brand new, specifically for EV use for $1000-$3000. That was a little expensive for my project, which only cost about $1300 total. My motor was from an electric forklift. I bought it for $50, cleaned it up, and installed it in my car. It works great.



For more information on repurposing forklift motors to power electric cars, please visit this link.
Maker17211 year ago
how fast does it go?
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