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Discussion Starter · #1 ·
Hi everyone, I am new to this website and plan on converting a 2009 Chevy Malibu LT into an electric vehicle. I have done quite a bit of research on how these conversions go. I am currently looking to find a suitable motor. I would like to be able to go 100km/h, however, I have read that with a forklift motor that is unlikely. The main reason I have been looking at forklift motors is that they are cheap and relatively easy to find, I also happened to read about the ForkenSwift. I intend on creating a lithium-ion battery pack out of 21700 cells and size them out according to the motor. Could anyone help point me in the right direction as to where to search for a relatively cheap motor that is capable of my expectations, or what to look for in a motor?
Thanks in advance!
 

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Hey, this topic abounds with strong opinions, so just a heads up - you will probably get a lot of conflicting ideas of what is most suitable.

Honestly, a big part of it comes down to what you want accomplish, and what your budget, skills, and interests are. Here are a few of the ideas you might hear, not really in any logical order:

1) Use a forklift motor: they are cheap, simple, and you can feed them a lot of power. They are great for drag racing cars, they will need maintenance, are not as efficient, or capable of regen - so they are not the top choice for a commuter unless budget is key. The controllers for them are also simple, and you can even build your own from plans available online. Off-the-shelf controllers are getting more rare, but a few places still make them. They will need some custom machining work done, as coupling them to the transmission will be a one-off solution depending on what you end up salvaging.

2) Buy a crashed leaf or other suitable donor vehicle and strip it for parts. I am not an expert, but there are a lot of options these days. This is like using a forklift motor, but in 2021, not 2001. Electric cars are all over now, and there has been quite a bit of work done in repurposing the motors and other parts. You can buy an off-the-shelf control board for the Leaf, which makes it pretty much as simple as the forklift route. There are limits to how much power you can get, so maybe not ideal for drag racing, but more efficient, has regen, and no wear parts (brushes) in the motor to worry about. You still need to make a custom adapter, but again, this has been done and I believe is pretty well documented by now.

3) Buy an off-the-shelf AC electric motor from an EV conversion supplier. This gets you the benefits of the leaf motor like efficiency and regen, but it is going to cost you significantly more. Like as much as buying a whole functional used leaf. There are pre-made adapter solutions for a wide range of transmissions, so you also do not need to ever set foot in a machine shop. I will say that this appears to be the route that is the most successful, in terms of projects getting completed; but I will concede that in fact throwing money at a project might be what is really driving that correlation. :)

4) Buy an off-the-shelf DC kit. Some people still swear by this, but the numbers dont make sense anymore. The motors and controllers are becoming rare, and will likely one day soon be gone entirely. Also, the price savings, if any, do not outweigh the fact that DC is just not as good for an electric daily driver car. It might make sense for very specific project goals, like insane torque, so dont take anything I say as a complete disavowal; but this route is unlikely to pencil out well.

So that covers motors:
As for batteries, making your own modules sounds like a lot of work. People have done it. Some have even claimed that they made something that was better than what auto manufacturers spent millions designing. Unless it sounds like a really fun project, I would suggest you look into used batteries out of crashed EV.
 

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Discussion Starter · #3 ·
I was hoping in making a vehicle for daily commuting purposes, and capable of vast distances such as a little over 400km. From how you are describing the forklift motor it seems it wouldn't be a viable option, and if I did choose it upgrading the motor late would prove to be a difficult task.
Leading to the question, how strong of a motor would be required for this? I want to make sure I choose a suitable motor.
Depending on the price and availability of Leaf motors I will most likely go down that route instead.
Thank you so much for all this valuable information, I will be sure to put it to good use!
 

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Carl summed it up nicely.

...

My concern, as a big picture, is that you might be spending more money trying to save money.

First:

Converting a car to an EV isn't difficult, but it is a lot of work. At the end of it, if all goes well and you overcome obstacles, you'll end up with an EV. In your case... you're going to end up with a 2009 Chevy Malibu.

After all the work and money you're going to put into the car, all you're going to get out of it is a 2009 Chevy Malibu.

Imagine a year down the road you could pick any similarly priced car to convert, would you pick a 2009 Chevy Malibu? Is that the car you're like "Aww yes, a 2009 Chevy Malibu, that's what I want to drive!"?

I'm guessing it's not. I'm guessing you chose this vehicle because someone gave it to you, or it's dead, or you got a deal on it, or something similar? And you're thinking "Well I've already got the car, so this will be cheap and easy!"? Maybe your mom gave you this?

Pardon the judgment of its drabness and unremarkableness, if it really would be the car you'd choose then go for it, but otherwise this is kind of like getting a boob job for your mom. Yay, bigger boobs, but... it's your mom. Not much to be thrilled about.

You're going to spend some time tracking down components, perhaps also spend some time tracking down a car.

Heck, even if the car is free, the conversion won't be, and it's probably not even the biggest part of the expense if you're already considering a 13 year old car.

Second:

Forklift motors are fine. There's people that've been driving DC motors for a decade. Regen is nice, but unless you live on a mountain you're not going to see much of an improvement in range, like, 5-10%. So it's not a big deal to give that up.

In terms of long-distance range, not commuting range, regen isn't going to give you anything, because you're not regenerating at stops (only hills, which is minor, most of your energy is still going to moving the vehicle down the hill at highway speeds). So, that's not a big loss.

There's no issue with top speed, not sure where you got that. All motors will have a top speed based on the voltage you give them. The concern might be "Can I chain together enough batteries to reach a high enough voltage". This is a concern for people who are using for example, large Tesla packs where it's not a capacity issue, it's that they can't make their building blocks smaller. You can't make 1/3 of a baby in 3 months. You can't make a battery 1/3 the size with 3x the voltage. This is not an issue for you, you can pick whatever voltage you want.

Since you're aiming for a cheap and crappy car, don't spend money on an expensive motor.

Third:

Batteries.

You're not getting 400km range in a Chevy Malibu. There's nowhere to put that many batteries. This might, barely, be technically possible if you went to absurd lengths like hiding pockets of cells inside the bodywork and such, but otherwise no. Half that would be reasonable.

Also, where are you getting 21700 batteries, and why did you choose them?

The great thing about small form factor batteries is that you can create packs any size and shape you want. The bad thing is that I've only heard of maybe 2-3 people who've done it successfully in a vehicle. I can't see that it would be cost effective either unless you have a magic source for them.

As someone who does have a magic source for free 18650s, and a tiny car that needs a perfect form factor, and trying to build an EV almost as cheap as possible, even I'm borderline on whether to use them or just buy proper cells.

...

The only thing I'd add to Carl's list is, since a Malibu is FWD, look at just swapping out a Prius transaxle/front assembly and going with a Prius inverter. It's pre-engineered to OEM vehicle standards (Toyota standards at htat, far more bulletproof than, say, Tesla engineering), you can pick them up for a hundred bucks apiece, and the replacement controller is cheap too.

Lay out your budget and your reasons for doing this and your interests and skills. You want to make sure you're choosing the best bundle of DIY decisions with those in mind.
 

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Discussion Starter · #5 ·
As you guessed the Chevy Malibu is dead, and I can get a hold of it for $500. The reason I chose it is because I figured it would be easiest/cheapest to get a hold of and the body is in good shape with no rust. However, it seems that looking into an alternative vehicle with a dead motor and body in good shape, and is more appealing might be a better idea. The reason I am worried about forklift motors is that I don't want them to fail on me from either the brushes wearing out or overvoltage. I understand that 400km is a high request I just also know that charging at a charging station takes a while. I was thinking of storing batteries underneath where the gas tank was. Also, I read that tesla used 21700 cells so I figured they would be appropriate. I have been debating about buying lots of dead laptop batteries and harvesting the good 18650s off of them. As I saw jehugarcia do this on youtube. My net budget will probably be about $2000, selling parts would be ideal for making this happen. I want to do this because I am interested in the making of an electric vehicle and it seems like fun, I am a University student in Electrical Engineering after all. Originally I wanted to make an E-bike, but Ontario has laws limiting the max speed, so I figured a vehicle would be a more reasonable mode of conduct. The reason for choosing an electric vehicle is that it is cheaper than paying for gas and eco-friendly.
Thank you for the willingness to help me along with this project. I look forward to your response!
 

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While I admire the "can do" attitude here, the project's range goal is wildly unreasonable, and all of the technical factors need to be reconsidered, starting with realistic goals and factual information.

One small detail: a 2009 Malibu only comes with an automatic transmission, which is unsuitable for an EV conversion, so instead of just mounting a motor to the transaxle you would be mounting the motor to a different transaxle which you would then need to adapt to the Malibu.

I understand that 400km is a high request I just also know that charging at a charging station takes a while. I was thinking of storing batteries underneath where the gas tank was.
The battery pack in a Tesla fills the entire space between the front and rear wheels, across the whole width of the car, one layer of cells (on end) thick. That's several times the size of a Malibu fuel tank, and the battery is several times the weight of a full Malibu fuel tank. It is not possible to fit enough battery in a car to get long range unless either the car is designed for it, or something like the entire back seat is sacrificed for it.
 

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Well, they say "You cant have it all" but what they really mean is "You cant have it all unless you can pay for it." With a budget of 2000$, you cant really have a whole lot of anything. If you really, really want to drive an electric car, you might be able to find a used leaf for 3000$. I saw one for 2500 that still got about 30 miles of range... You might get a few years out of something like that.

As far as a conversion goes, you would basically be limited to what you can find for scrap prices. A forklift motor might make sense again. You probably wont find a whole wrecked leaf at your budget, and that control board is 500$, so you can basically forget that route. Same with buying any off-the-shelf parts. Even having an adapter made would eat a very large piece of your budget.

I think if you are serious about making this work, you are going to have to look at this as a learning experience. If the finished car can drive 30 miles on a charge, that would be a win. It will likely look like something even Mad Max would be wary of driving. Most likely your budget will bleed out in a thousand little unforseen costs, and the thing will never move - but you will no doubt learn something from that outcome, too. If you are going to scrap and scrounge, you will probably want to budget several years for this project - so make sure you have a good spot to park it while the project stalls, and you have to go look for parts.
 

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A miles zx40 and Comutacar are well within this budget and usually just require minor tidying up and batteries.

trouble with any low budget EV, is that your range will be very limited<50
 

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Discussion Starter · #9 ·
Thank you for all your insightful replies, and what limits a budget EV’s range the battery capabilities or the motor? Also how difficult is it to upgrade it later on?
 

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Discussion Starter · #10 ·
I forgot to mention I have a motor that isn’t too big and I think it’s original purpose was for industrial fans. The ratings I can remember off the top of my head are: 3.3amps and 230V. I hear people mentioning motors with ratings as low as 72v. Do you think it would be worthwhile installing this motor or finding a forklift motor?
 

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Discussion Starter · #11 ·
Not the motor I mentioned but I am able to get this for about $500 usd + $457.68 usd shipping, would this be worth it?
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The batteries are the biggest expense - figure you will be hard pressed to get them for less than maybe 130$/kwh, and you will likely get 3 or 4 miles per kwh. So, figure you will spend around 40$ of 50$ per mile of desired range. If you have 1000$ to spend, you might get 25 miles of battery.

The next biggest cost is a motor controller. You can build a DC controller for a few hundred bucks if you are handy with a soldering iron. A new DC controller will likely cost 1500 at a minimum, up to 2500$. You can sometimes find used ones on the classifieds for less, but they are sought after, and sell pretty fast.

After that, getting an adapter plate and hub made is big expense - you can do it yourself, but you might end up ruining the motor or the transmission in short order if you dont do a good enough job. If you know a machinist, you might be able to make something that will work.

The ratings I can remember off the top of my head are: 3.3amps and 230V. I hear people mentioning motors with ratings as low as 72v.
I thought you were studying to be an EE? You do realize that 3.3 amps and 230 volts is only 759 watts, right? And a horsepower is like 750ish? It would be faster to walk.

Oh, and that other motor is only 1.5hp, so still better to walk.
 

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Discussion Starter · #13 ·
Thank you, I heard from BenjaminNelson that electric HP is not the same as ice HP, which didn’t make sense to me, and I am just in my first year of EE. However I do have a soldering iron and equipment so making a controller would be very possible do you have any resources as to how it’s done? Also I would really appreciate it if you wouldn’t mind helping me understand what a good benchmark is for a motor.
 

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Check out: EcoModder Forum Wiki for some info on making a DC controller. I have not really done a lot of reading on the subject, so I am not super knowledgeable about that whole process.

As for selecting a motor, there is a giant thread about forklift motors that is worth at least skimming through. I am not nearly an expert on car power requirements, but a horsepower is indeed a horsepower. I hope someone will chime in with a succinct explanation of how ICE peak horsepower numbers are not quite the same as an electric motors continuous power rating, because I am not quite sure I would explain it right.

As a general rule of thumb, though? When looking for a forklift motor, you want a roughly 9" diameter series wound DC brushed motor that weighs around 150lbs.
 

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As you guessed the Chevy Malibu is dead, and I can get a hold of it for $500.
You're going to be showing this off to your friends. You're going to be like "Hey I built this car!" and they're going to say "Why?"

The reason I chose it is because I figured it would be easiest/cheapest to get a hold of and the body is in good shape with no rust.
That's important, especially with Ontario's inspections, but it's still a 2009 Chevy Malibu.

To be frank, I don't know if you can do this for your budget, even if the car was free.

That said, Damien McGuire, on a challenge, built a 1000 euro EV including the price of the car, which is close-ish to $2000 CAD. But his didn't have much range.

Even if everything but the batteries was free, I'm not sure this would be possible for you. Not for anything outside of a commuter car.

The reason I am worried about forklift motors is that I don't want them to fail on me from either the brushes wearing out or overvoltage.
Worry about it after a decade of reasonable driving. Overvoltage likewise not a concern.

I have been debating about buying lots of dead laptop batteries and harvesting the good 18650s off of them. As I saw jehugarcia do this on youtube.
When was the last time a laptop used 18650s?

There is already a market for used laptop batteries from other scrapers, so you're not going to get them cheap. And it's going to take you like, a year or two to get enough.

Even if you got them free, the time to disassemble, test, and rebuild them will take you more time than their value is worth compared to minimum wage. So unless you have a work-from-home tech support job or something similar where you have bottomless free-ish-but-have-to-be-there time, just get a job and buy better cells.

As I said, I'm currently doing this, with cells that were free, and I'm borderline on doing it.

I doubt you could buy 18650s for cheaper than you can buy OEM batteries.

selling parts would be ideal for making this happen.
I think you will be upset at the sale price of 2009 Chevy Malibu surplus parts on a dead Malibu.

If this is true, then what's stopping you at the Malibu? Buy crashed cars and pull parts out of them for sale until you can buy an EV.

I want to do this because I am interested in the making of an electric vehicle and it seems like fun
Yes, good, you find it fun to do this, not just to get to the end result. If this was not true, or stops being true, stop doing this. You're going to have to love it because you're going to have to cut ever time vs. money corner you can.

Originally I wanted to make an E-bike, but Ontario has laws limiting the max speed
1 - Almost no one checks.

2 - The rules are about how fast you can go before the motor has to stop helping you. There's no actual top speed of a bicycle other than the speed limit on the road. Also, riding a bicycle-quality vehicle at motorbike speeds is a waiting game before it kills you. Otherwise, it would be a difficult ticket to prove in court without a vehicle inspection. Also, you'd probably get away with it for a while. Also the ticket is probably small.

3 - Ontario has winter. A bike isn't a complete solution.

4 - Read this: Driving an e-bike or moped? Know the laws say OPP You have 3 sets of non-motorbikes in Ontario. 1 - E-bikes (max 32km/h), 2 - 50cc scooters (max 50km/h), 3 - 50cc "Low Speed Motorcycles" (max 70km/h). The latter two require a plate and insurance, but insurance is dirt cheap, like, $50-150/year.

5 - Bikes do not have enough space to carry much battery, you're commuting in them only unless you're going very slowly.

6 - You're not going to impress anyone zooping around on a scooter. Back to the Malibu problem.

7 - A bike is a less ambitious project, with less storage space needed to build it, more achievable, and you'll learn more. It's a good foot in the door before you convert an EV.

The reason for choosing an electric vehicle is that it is cheaper than paying for gas and eco-friendly.
Also good reasons.

Do you need a car? If you need a car, and you need to be able to go city to city, it's cheaper just to buy a gas car and drive it. If you already have a car and want to save money, see how much you'll actually save compared to having to insure a car anyway. But if you do, then perhaps consider a low speed motorbike for the 95% of your trips it would be okay for, 6 months of the year.

...

If you want to go cheap as possible, scrap forklift is probably still the way to go. Borderline between that and the Prius transaxle. Your adapter plate is able to be hand made with DIY effort, (just not on the Malibu). You're in university, spread the word and you'll probably get some free materials and machining from the shop for a case of beer.

Controller, I dunno what's still cheap. There was some promise of a DC controller from a prius inverter, one person who's really tried hit a snag that may or may not be universal. But that'd get you in for under a couple hundred.

You have all kinds of extras you're going to need too. Wiring and pedal and vacuum pump and contactors, that alone might eat up 1/4 of your budget even if you're thrifty.

...

Another option is to just buy an old Prius in ugly-but-good condition. Something dented up so the value has plummeted but the bones are still good. Then go to the junkyard and pull off nicer doors/panels so it's less embarrassing to drive. Just drive that, as a Prius (it's great on gas), and add more batteries to it as you find good deals on batteries or whatever. Add the batteries to the back seat or trunk or something, to extend the EV range of it. Then when that starts looking good, as you pick up even more batteries, plan on yoinking the engine out, sell it if you can, and filling the space with lots more batteries and such.

That way if you give up on the project or get sidetracked or it's too expensive or whatever, you still have a cheap car that's cheap on gas, that you haven't started chopping apart or sunk too much money into.

Back to problem #1... you're not going to get laid driving a Prius.

How soon do you want this done?
 

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Discussion Starter · #17 ·
How soon do you want this done?
It would be ideal to have this finished by July.
To be frank, I don't know if you can do this for your budget, even if the car was free.
If the Malibu isn't possible because of the transmission, and a lot of energy is lost in the transmission, why not just take it out and connect the motor(s) directly to the front wheels?
That's important, especially with Ontario's inspections
I am concerned about the availability of getting it safetied. I have been informed that it is difficult to get a car without OEM parts safetied, how would I go about that?
If you need a car, and you need to be able to go city to city, it's cheaper just to buy a gas car and drive it.
I was thinking of just getting a gas car for this reason, and may just save up for a more reasonable conversion, however, I like the idea of being able to take a forklift motor and putting it in a car, as you stated I need to increase my budget.
That being said I would like to put forklift motors directly into the wheels, which I think would be more efficient than wasting a ton of energy on the gears in the transmission, and just switching directions by hot-swapping polarity. Is this a feasible idea with the current budget, or do you recommend buying a gas car and saving up for an EV conversion?
Thanks again for all the helpful advice!
 

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It would be ideal to have this finished by July.

If the Malibu isn't possible because of the transmission, and a lot of energy is lost in the transmission, why not just take it out and connect the motor(s) directly to the front wheels?

I am concerned about the availability of getting it safetied. I have been informed that it is difficult to get a car without OEM parts safetied, how would I go about that?

I was thinking of just getting a gas car for this reason, and may just save up for a more reasonable conversion, however, I like the idea of being able to take a forklift motor and putting it in a car, as you stated I need to increase my budget.
That being said I would like to put forklift motors directly into the wheels, which I think would be more efficient than wasting a ton of energy on the gears in the transmission, and just switching directions by hot-swapping polarity. Is this a feasible idea with the current budget, or do you recommend buying a gas car and saving up for an EV conversion?
Thanks again for all the helpful advice!
You need gears to get enough torque to start moving up a hill.
Most motors are happiest somewhere north of 2000rpm, the one in a leaf is better around 10,000rpm

An antique manual transmission is best
 

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If the Malibu isn't possible because of the transmission, and a lot of energy is lost in the transmission, why not just take it out and connect the motor(s) directly to the front wheels?
Very little energy is lost in a manual transmission, or even in a modern automatic.

But this starts to get at the reason:
Most motors are happiest somewhere north of 2000rpm, the one in a leaf is better around 10,000rpm
The speed that the wheels turn is determined by only the road speed and the tire size. The Malibu wheels turn at 791 RPM @60 MPH, or 819 RPM @100 km/h. That means that you can use a substantial amount of reduction gearing (the Nissan Leaf uses about 7:1, for instance), and the greater the ratio of the gearing the more torque you get to the wheels to accelerate at low speed.

That being said I would like to put forklift motors directly into the wheels, which I think would be more efficient than wasting a ton of energy on the gears in the transmission, and just switching directions by hot-swapping polarity. Is this a feasible idea with the current budget...
That won't work, on any budget. Aside from the lack of the needed gearing, huge mass bouncing up and down with the wheels is very bad for ride and handling, and sufficiently powerful motors of the type you can salvage from something like a forklift won't fit anyway.

Yes, direction can be changed by switching the polarity of the field winding in a series-wound brushed motor, or by the controller of an AC motor.

An antique manual transmission is best
Well, a manual transmission or a single-ratio transmission is ideal, depending on the motor. That generation of Malibu was not available with a manual transmission. The car is front wheel drive so the transmission and final drive are combined in one unit, which is called a transaxle; the usual way to get a single-ratio transaxle is to the use the one the motor is already attached to in the EV that you salvage the motor from.
 

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Discussion Starter · #20 ·
That won't work, on any budget. Aside from the lack of the needed gearing, huge mass bouncing up and down with the wheels is very bad for ride and handling, and sufficiently powerful motors of the type you can salvage from something like a forklift won't fit anyway.
What if I were to mount two motors under the hood, but use belts to connect to the wheels so I can harness the power of two motors? Would this overcome the torque issue?
 
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