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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 DVD available at 300MPG.org
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 DVD available at 300MPG.org
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Signing UpStep 1Get a car.
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!
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!
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i read your article about converting Geo Metro to electric car , i was really thrilled.:) It looks very easy :)
I decide to convert some old car to electric car to get to work and back. I have few questions, which i need to answer, if you could help me:
- What car should i pick? Do i have to watch some special parts of car (transmition) I was thinking about Mitsubisti Colt 1996 or Peugeot 206 1998, what you mean?
- Why do you use exactly forklift electric engine?
- Can you tell me what power (kW) and torgue (NM) should the electric engine need to have?
My idea about the electric car is:
Day distance/range: 70-80km
Max. Speed: 80-90 km/h for 10km, and rest 50-70km/h.
Thank you for help.
Miro (mirio46x), Slovakia (Europe).
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
http://www.instructables.com/id/Homemade-100-HP-Motor-Controller-for-an-Electric-C/
for a go cart conversion? I cant afford any other controllers.
That's the controller that's in my car right now.
All the costs, help, and info are right there.
Im into RC cars. What you're saying with the Nissan leaf is that the wall charger can charge the battery faster then the motor can drain it. I charge my RC battery at 4 amps, it's a 4200 mah battery, so it takes 1.2 hours to charge. But I can run it for up to 2 hours depending on how hard I run it at. If your generator is making less then you use to run it, you're going to drain the battery much faster then you can charge it.
As for Lipos, they are much more exspencive and can exsplode if damaged, thy work in cars like the Leaf, but for home projects, it wouldn't work on a big scale
A quick question regarding the transmission, You say you bolted the motor directly to the transmission, So Im guessing you can't change gears, not that you really need to, so what gear are you running in?
The drive shaft of the motor is coupled to the driven shaft of the transmission, in place of the flywheel pressing against the clutch, which is on the driven shaft.
It can still shift fine, it's just that there is no clutch in there now.
I typically drive in second gear in town and third gear on the 45mph road.
The motor has enough torque that I can just put it in a single gear and leave it there.
If the motor is running at 50% power to move the car, then you hook a generator up to the car as well, it takes energy to move the generator. So if the energy it takes to run the generator is 10%, you are now using 60%, 50 for the car 10 for the generator. But, no generator known to man, is 100% efficient, they make noise, heat and other things on top of energy.
Lets say the generator makes 5% energy, but it takes 10% to run it.... you lose 5% for no reason.
As for the dual batteries, that's great! but the motor needs a certain voltage, and doubling the batteries add too much weight. In some other cars this would work fine, but it's just a run about, great for popping down to the local supermarket ;)
the nissan leaf takes 30 mins to charge at a refueling station itll drive twice as long as that in that time it could have charged the second battery
a lipo one that is they r alot lighter than the nicad or a regular car battery so u wouldnt add to much more weight no more than have the trunk full of suit cases
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.)
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.
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?
You need a completely different type of device to control the speed of an AC motor than that of a DC motor.
HOWEVER, I do know several people with in interest in DIRECT DRIVE washing machine motors. Some front-loading washers now have the motor directly on the tub, instead of connected by a belt. Those motors have a plenty of torque, and might be modified to be HUB MOTORS - going directly on the wheels of a vehicle.
If I remember correctly, Washing machine motors are Universal, Meaning.... well. I'm sure you already know.
I've tried to run a Vacuum motor from a 12 amp, 1 1/2 HP vacuum cleaner. It worked very well. Spun slower than usual, but hey, it's only 12 volts with over 4 amps going through it.
But I can't recall trying a washing machine motor, I may have, but still, I don't remember. Brighten me on the subject.
The motor I used in my electric car weighs about as much as an entire washing machine. (Ok, I exaggerate, but not by much....)
In this case, drive motor = washing machine motor.
Anyway.. I found a kit online at : http://www.e-volks.com/electric_car_conversions.html? and was wondering if I can use that. Or do you think it's too cheap? I find it extremely affordable. Thanks.
The max voltage of the controller will limit speed, but not a problem if you are just in the city anyways.
"Can't you just put an alternator on it so it runs forever without recharging?" or some variation on that is a question I get almost all the time!
It's usually well-meaning people who just aren't thinking about where the energy comes from.
also the downside to that is it isn't geared down. Connecting a 100+ HP motor to the transmission is going to work better than connecting them directly to the tires.
First, when you say the peak horsepower in 96.5 hp, this peak horsepower occurs when the gas peddle is fully compressed and not the constant horsepower correct?
Second, how can you be pulling 500 amps from the batteries when the capacity of the batteries is only 100 AH? Does the controller amplify the amps?
Third, how did you figure that your cars uses about 300 WH per mile? what calculations did you do? I am trying to understand all the calculations involved in this type of project.
Thank you
How many watts or horsepower a motor uses depends on which gear you are in, the weight of the car, if you are accelerating or not, etc. When you are at a stop, you use 0 watts.
For the batteries, AMPS is a rate of energy flow. AH or Amp-Hours is a CAPACITY. It's a bit like comparing miles-per-gallon to how many gallons a gas tank is - they are two different things.
To figure how many watt-hours per mile, a simple way is to reset the car's trip odometer, go for a drive, and return home. Plug in the car's charger through a device that tracks energy usage. I use one called a "Kill-A-Watt". When the charge cycle is complete, divide the watt-hours used to charge the car by the number of miles on the trip odometer to get watt-hours per mile.
HP = torque x RPM / 5252.
The acceleration of the car then depends on the horsepower or watts produced by the engine, and the other forces on the car (drag and friction and gravity if going up or down a hill) which depend on the speed, the weight etc. Is this not correct?
For the batteries, I guess I worded in a bad way. 100 AH tells us that we can pull 100 amps for one hour or 1 amp for 100 hours correct? So pulling 500 amps would only allow the batteries to run for 12 min or 1/5 and hour if they were fully discharged, right? (500 amps X 1/5 hour = 100 AH)
Since I am doing a feasibility project, checking the possibility of turning a truck into an electric truck, I do not have any equipment to check the watt-hours per mile and need to do an estimate based off numbers and calculations. Do you happen to know how to do this?
You are correct in that gears do NOT create power (horsepower) they only swap torque and speed. A typical gas car uses the transmission to match the engine to the road in terms of speed (usually upshifting) and torque requirements (usually downshifting) Many electric cars use fewer gears because they have a larger range of torque than a gas engine car. For batteries, you have that about right, exept that it is a tad more complicated than that once you figure in the Peukert effect
You can do a rough estimate of of how many horsepower/amps/volts you will need with an online EV Calculator. You can find one HERE.
MPH = RPM *Circumference / gear ratio * 0.000947 for converting from inches per minute to miles per hour.
Using a motor performance graph you can then find the torque and amp at any rpm and thus any speed. Using the torque you are able to figure out acceleration and using the amps helps you determine the range. When engineering a car you determine the gear ratios based off what gives you the best performance. Since I already have a transmission the process I described allows you to estimate your performance. Is this correct?
I never did any of that though.
In my case, I had never built an electric car, and was really looking for just an "around town vehicle". I have another (internal combustion) vehicle that would be dedicated to long trips.
I simply found an electric motor that looked plenty big, and went with it. I'm sort of an "off-the-cuff" tinkerer/designer. My thoughts tend to be more of "will this work or not?", "can I afford this?", "Is it good enough, or not?".
I know many engineers that are good on paper, but micro-manage a project so much, that they never start it in the real world. It's death by overdesign. I am a strong proponent of just throwing yourself into something.
Learn all you can, do your reading and research, talk to everyone you can, but at some point, just start actually working on the project. Get the truck, yank the engine, and go from there. The small successes of removing the gas tank, pulling the engine, etc. are very motivating and keep a person excited and on task with the project.
Good luck on your project!
-Ben