Build your own Electric Car!

Step 9 Now you make one!

An electric car really is fun to drive!

My house is on a renewable power program, where I get all my electricity over the power lines, but coming from bio-gas, wind turbines, and other renewable energy sources.

Doing a calculation on energy consumption, comparing gasoline and electricity, the car gets the equivelent of about 130 miles per gallon

This has been a fun project to work on and I have learned tons doing it. Keep in mind that I have NO background in electronics or engineering. All I did was go to the library, start talking to people, and learn what I could!

If I can do this, so can you!

So how about it? Are you building an electric car or have any other DIY Green Tech? Let me know!

You can stop by 300MPG.org to see the videos that my friends and I are making to teach you, step by step, how to build your own electric car!

I found that there was a lack of instructional videos in the world of electric cars. I bought a couple, and they all were TERRIBLE! So, I made my own! Stop by 300MPG.org to check it out!

Take care, and keep it green.

Thanks,

-Ben

PS: if you enjoy the videos, please give them a high rating, this helps me to be able to keep making them!

For more photos of this project:
http://gallery.me.com/benhdvideoguy#100161
http://gallery.me.com/benhdvideoguy#100222
http://gallery.me.com/benhdvideoguy#100273
http://gallery.me.com/benhdvideoguy#100287

Comments

[msihcs]

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.

[bennelson]

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.

[BigTurd]

Seems to me you could have saved a bit of power (range) by removing the transmission altogether. This cuts some HP loss thru the gears not to mention some weight etc.

The proviso being that the traction motor can reach the rpm's necessary for your type of driving conditions. If it can't, perhaps you can pop in a different rear end ratio that better suits your needs.

Another note, there's likely a way to use the motor for regenerative braking to charge the batteries. It won't completely recharge them but adds a little extra range.

Just some thoughts.
bc

[burglebox]

I'm fairly certain you need the gear reduction to increase the torque of the motor. You can get by with a "weaker" motor by allowing it to run at higher RPMs. The same thing applies to gas engines; they spin at thousands of RPMs only to be reduced and have their torque increased by the transmission.

Also, with DC motors at least, operating them at high voltage well below their RPM rating can cause them to burn out.

[BigTurd]

My thinking is, the existing rear end gear ratio is probably 3.4 : 1.
He might throw in a small gear reduction box if not already on the motor.
A gear reduction box is much smaller & lighter than a transmission.
This might provide all the gearing to keep the motor in its torque range?

I would like to create a diesel / electric like trains use.
Who knows...Might work in a car?

[bennelson]

It's a front-wheel-drive car, so there is no "rear-end" gear ratio per-se. I typically drive the car in 3rd gear, as though it were an automatic.

You are quite correct in that a gear reduction box would work well. The Solectria Force was a factory-built Geo Metro with an AC motor and a gear reduction box. They worked quite well and did freeway speeds. The Tesla roadster also uses a dedicated gear reduction.

In this case, is it worth it to do all the work to figure out what the correct gear reduction box is, fab mounts to connect it to the car, and pay all the money for the part, when the existing transmission works fine? I spent about $1300 for the entire project. I tried looking up a for sale gearbox from a Solectria and wasn't able to find any. At least the Geo Metro is a vehicle that somebody else has already designed a dedicated gear box for.

Ever lifted a Geo Metro transmission? It's not that big or heavy. I don't think there would be a lot of weight or space advantage to switching to a dedicated gear box. I have also heard of guys locking their transmissions in a single gear and removing the unused gears to save a little weight.

[gunguru1]

Just finished reading this great project! This has given me some really good ideas... I have an old beat up VW Fox. Its like a diesel VW pick-up with a rabbit or jetta front end. I doubt the engine will ever run again and was thinking how much more room for batteries could .........maybe add a little more range to it!!! I have programmed a lot of DC motor controllers in the past and think with a little research I could write some great acceleration ramps that could make it more efficient!! Also, I was wondering how the braking works? Is the controller programmed for a coast to stop function or does it ramp down? Ramping down could actually be sucking a lot of useless power. In some of the more modern AC controllers you can change the frequency and voltage and force the motors to go faster than line frequency (60hz) will push it! I have not tackled anything quite so big but, I did finish a 48v self powered bicycle trailer..... Anyway, nice job!! Nice to see someone using their head!!

[Justdoofus]

I'm only 16, but I am about to pull the biggest project of my life soon. This.
I have already (before even driving!) started searching for alternatives, or more efficiency that I could squeeze out of an engine, or other power source.

I have tried multiple things so far, and my very latest project is a vapor carburetor. It simply pulls air into the canister, through the gasoline, and bubbles it. Bubbling causes the gas to vaporize. I even designed a heater out of copper wire as the vacuum causes the gasoline to slush up (close to freezing temperature) and reduces vaporization....

One thing that I have considered was an air powered engine. It's all in my head, you see. I already have an idea for a pneumatic lawn mower engine. I even wrote schematics and crap for designing. Just a matter of time until I can get myself into this garage soon..

Anyway, back to the subject (As you can see, I am very excited. Haha.)
Basically you have;
1. Electric Motor (48, 72v) Preferably fork lift 'drive' motor.
2. Adapter plate to fit motor and going to transmission drive gears.
3. Two piece coupler to connect motor to transmission..

My question(s) are:
You know how the engine and the transmission (Or clutch, rather) is connected to the transmission? I saw that in one of your pics, that the side was opened up, allowing for a clear view into the transmission where the drive-shaft goes into the transmission.

Is that not supposed to be sealed up and oiled properly in order to prevent overheating and preventing dust from going in? (Or is it because it's not a gasoline engine, and barely any heat is being created.)

And also, can't I just take a regular non-hollow tube and weld it straight to the transmission shaft?

Thank you for your time. Oh, and beautiful car for this project too. It's perfect. though I'd still prefer a small Mazda car. (Might beable to get that car... broken alternator, place I live at doesnt want to get it fixed because of many other electrical problems.)

[bennelson]

A Mazda Miata would make a great little electric car. The only issue with that one is it's rather limiting in where you put the batteries.

On my project, the shaft of the motor is connected directly to the driven shaft of the transmission by a coupler that that fits between both shafts.

I don't see any reason to do any welding onto a transmission shaft - much easier to simply connect to it in the same way that the clutch disc did.

The bell housing of the transmission really isn't sealed up all that well, even when stock on a gas car. That's the space for the clutch and flywheel. There should be a bearing on the transmission driven shaft back IN the transmission a bit. No matter what, you need to make sure that the outside end of the transmission shaft gets supported. Typically, it goes into a bearing in the middle of the flywheel. On a clutchless conversion like mine, it is supported directly by the coupler and motor shaft.

[Justdoofus]

That's exactly the car I was thinking. The only place that I can see to place the battery pack(s) would be under the seat, or in place of the seat. I'm probably going to be the only person in the car all the time. So it doesn't matter about the seats in the back.

Anyway: I still don't see how I can connect it to the transmission. Does the clutch bolt to the transmission?..
Also if I wanted a clutch, can I just go the simpler (I wouldnt say that) route and just place the electric motor shaft directly onto the clutch as if it were an engine?

[WhiteTech]

You wouldn't need a clutch, the thing about electric motors is they have nearly 100% torque even when they aren't moving, so changing gears isn't really needed

[dpater]

Ben,
Put these words in You-Tube search

WORLDS FASTEST street legal ELECTRIC CAR

you will love it!

[bennelson]

Yeah, I am familiar with the White Zombie. It's a very cool car. A while back, I got to see one of the other cars designed by Plasma Boy. Very nice car.....

[riddler357]

Great Idea!!!


was wondering ..and is a probably a stupid question but the motor you used is it a DC motor? I can't image it being a AC with getting a converter. I know they have DC motor but they are really small HP, but i guess you wouldn't need it for a small car. I was thinking of converting my truck into a eletric truck, with a few mods on it. I was also thinking that i could use some solar cells to keep a charge, but not sure if that would work. Anyway great project!!!

[jason the redneck guy]

Fords are easy to work with, as they have electric power steering and electric power brakes. Electric ford focus too expensive? make your own!

[Squ33]

can you shift gears as you would for a gasoline engine while moving? If so, do any problems arise?

[bennelson]

It shifts fine. You just need to wait a second or two when going from one gear to the next for the speed to roughly match. First gear is completely unneeded. I can pull away from a dead stop in fifth gear. Shifting gears mostly saves power more than anything.

[bennelson]

The more I drive the car, the less I shift. 2nd gear handles everything from 0 to 35 mph. In town, all the roads are 25 mph, and even on the 45 mph roads I drive on, as long as there isn't too much traffic, going 35 is fine. 2nd pulls less amps than 3rd, making the batteries last longer. I've gotten this car up to 70 mph (experimentally running 144V) so for that you have to use a higher gear, but for lower speeds, I don't even bother shifting.

[dpater]

So is the clutch system removed?, I am very interested in what you have done here, well done!

[bennelson]

Yep, no clutch.

[alysssalyn]

I just sat for 2 hours and read this whole blog. I have a 93 Pontiac Sunbird... its a heavy and busted up load of dirt... I live in Wisconsin and was trying to figure out WHERE you live cuz all of it looks so familiar. Piggly Wiggly... haha. I'm so against gasoline cars but I can't go anywhere unless I want to take four days to walk to the grocery store... haha. I love that you did this. It makes me want to SOOOO BAD. but I know nothing about cars and because of that my Ponti has little to no liquid in it... (windsheild wiper fluid, coolant, no oilchange in months... run outta gas constantly) its goin downhill fast but everytime I do put something in it its usually wrong or i have a busted line.. i hate cars. i'm rambling... this was awesome to read! just lettn you kno haha

[bennelson]

I'm in Oconomowoc, WI. Come see me sometime.

We also have a group of guys who meet regularly in the Milwaukee area to work on electric vehicle projects.

See:
http://ecomodder.com/forum/showthread.php/milwaukee-electric-car-club-running-event-6699.html
for details

[flas1013]

Bennelson,

First of all, I found your "instructable" very informative. I am an EE (in your area) with some past experience on the Railroad which translates well into electric cars. I have been thinking about working on a project myself and checking out your meetings. I'll go to the link you provided and see if I can find out when the next meeting is from the web-site.

Thanks for the Info

[bennelson]

The Milwaukee Electric Car Club currently meets at the Milwaukee Makerspace. ( http://www.milwaukeemakerspace.org )

Come on out during a meeting to make new friends and work on electric cars.

[LetsExplodeSomething]

I'm from Milton,Wisconsin nice I'ble by the way! 5 stars in my book

[alysssalyn]

I KNEW IT! i drove thru there once and thought it was the strangest out of the way town hahaha... but i shouldnt talk my hometown is black earth. im currently living in chicago but moving back to madison when i start college in the fall FINALLY. i'll check it out!

[Lasant]

First off, this is beautiful and inspiring. Thank you so much for sharing.

I was curious as to whether it would be feasible to integrate some sort of generator with the sole purpose of charging the batteries as your drove - increasing the distance you could drive on a single charge.

[bennelson]

As a matter of fact, you could. This would be called a serial hybrid and is the concept that the Chevy Volt uses. See my further experimenting with a generator in the car at: http://www.instructables.com/id/DIY-Plug-In-Hybrid-Car/

[Lasant]

Badass! I can't wait to read it in further detail. This is so exciting. Thanks for the quick response.

[tizart7]

Inspiring ible !!!!

I am based in the Kingdom of Bahrain, Middle East. Gas is cheaper than water here but I would really like to try making an electric Car down here.

Keep up the good work. Now I will start looking for some good size Forklift motors.

[ve2ypd]

vraiment super...félicitation , très beau projet

[BH-Inspector]

Very nice project. In Germany this is not possible because the local "TÜV" (german Technical Inspection Association) would say NO to such a selfmade electric car.

[martyjr9]

nice mod how do you shift the 5 speed tranny with no clutch ease it in and let the synchros do the work?

[bennelson]

You just shift. It really is WAY easier than you think it is. The electric motor does NOT put pressure on the drive system the way a gas engine would. It's pretty easy to put in and take out of gears without any clutch at all. Also, since the electric motor has a wider range of RPM that the gas engine did, AND more torque, I shift a lot less. First gear is totally un-needed. The motor actually has enough torque to pull away from a dead stop in 5th gear (although slow and using lots of amps.) 2nd gear will do 0-35mph 3rd gear will do 0-45 mph. Most of my driving is in town in 25 mph zones, so I just put it in 2nd and use it like DRIVE in an automatic.

[ceknight]

Probably one of the best done Instructables I've seen yet! Very inspirational! Has me wanting to get right out there and do the same. Of course, might have been better suited when I lived on the pancake flat Eastern Shore of Maryland. Not too conducive to the hills and long distances up here in Vermont. Impressive.

[allenmt]

 hey im only ten but could u hook a generater up to the rim or something and recharge the batterys while driving

[Nyxius]

It is a nice thought, but generators and motors are not very efficient. When it comes to converting mechanical energy to electrical energy and and electrical to mechanical energy there is always some energy lost in the process.  Running a generator from the motor will make the motor work harder to spin the wheels.  This will make the motor draw more amps.  In the end the motor will draw more amps trying to rotate the generator than the generator can produce.  This will result in the battery draining faster with the generator, than if there was no generator.

Good effort though.

One suggestion along similar lines is that he may be able to use hub style motors as brakes, thereby recovering some of the energy lost during braking.

[gitchermotorgoin]

nice job...what's the car weigh now? i'm thinking of adding a forklift motor to the rear axle of my civic, leaving the ic engine up front, and using the motor for takeoffs, ic for hispeed. any ideas, linx? thanks and more power tou seen
'killacycle?" 

[bennelson]

 That rear motor on a Civic idea would be a "through the ground" hybrid. I think those are a great idea, but I don't know anyone who has actually done one.

Ideally, you would want some way to disconnect the motor from the rear wheels when you are driving on ICE so that you don't have any drag from the motor and wear on the brushes (if DC) - Brushless DC or an AC motor might work well.

Yes, the Killacycle is VERY cool.

[jimmerforpoy]

so how much does it weigh?