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Discussion Starter #1
So after some deliberation it was decided to abandon the ford explorer and go for something simpler.

Rebuilt cars from the ground up and can fab anything or get it done at my brothers machine shop.
Hoping for 50 miles roughly and able to reach hwy speeds 70mph
Trying for minimal funds as we are doing this as a project for school.

Now for parts
94 geo metro manual transmission
Advanced dc motor 36/48v from a 12k# crane forklift
300a 144v motor controller
10s bms
18650 li ion cells 10s 20p packs 144v 100ah
12v accessory battery for ps pump, brake booster, and ac compressor. motor from treadmill

Charger is my biggest hangup. Was thinking use 2 1500w dc boosters and split the battery at 72v

Let me know what you think.

Thanks
 

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So after some deliberation it was decided to abandon the ford explorer and go for something simpler.

Rebuilt cars from the ground up and can fab anything or get it done at my brothers machine shop.
Hoping for 50 miles roughly and able to reach hwy speeds 70mph
Trying for minimal funds as we are doing this as a project for school.

Now for parts
94 geo metro manual transmission
Advanced dc motor 36/48v from a 12k# crane forklift
300a 144v motor controller
10s bms
18650 li ion cells 10s 20p packs 144v 100ah
12v accessory battery for ps pump, brake booster, and ac compressor. motor from treadmill

Charger is my biggest hangup. Was thinking use 2 1500w dc boosters and split the battery at 72v

Let me know what you think.

Thanks
I am probably going to pull apart my '97 Swift, and sell the parts this winter.... It is lacking only a Controller (old Curtis 1221 bit the dust after 20k miles), and half a battery pack which I already sold. I could ship you the whole thing and save you a ton of time....

check out the whole build:
http://envirokarma.org/ev/
 

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Discussion Starter #3
I am probably going to pull apart my '97 Swift, and sell the parts this winter.... It is lacking only a Controller (old Curtis 1221 bit the dust after 20k miles), and half a battery pack which I already sold. I could ship you the whole thing and save you a ton of time....

check out the whole build:
http://envirokarma.org/ev/
Thanks, what kind of money we talking and timeline? We have a timeline for construction so we can test her theory in time for the Science fair. Have to be done by December.

Further on that if you don't mind me asking why you tearing it apart?

Looked at your website and there is some awesome information there. Actually your Li-ion battery got me rethinking the size and structure we are thinking of using.

I also looked at the Nissan Leaf I think the cellular structure of that makes for swappable parts without completely tossing the battery. Thinking we might build our packs in a similar way 2p20s and then parallel sub groups to voltage then those serial to amperage.
 

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I also looked at the Nissan Leaf I think the cellular structure of that makes for swappable parts without completely tossing the battery. Thinking we might build our packs in a similar way 2p20s and then parallel sub groups to voltage then those serial to amperage.
I think there's a typo in there, since connecting cells or modules in parallel increases current capacity and connecting them in series increases voltage.

Like every other modern production EV, the Leaf has cells connected in parallel groups to reach the required current capacity (two cell groups in the traditional Leaf configuration), then two groups in series to make a module (again, in anything before the Leaf Plus/e+), then 48 of those modules in series to make the full pack. It is unusual in that it has smaller modules (only 2S) and therefore more of them (48) than typical EVs, which can have as few as four modules (Tesla Model 3) and typically 8 to 16.
 

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Thanks, what kind of money we talking and timeline?
if we can come to grips on money, we can arrange shipping and get it to you as is.... only thing you'd have to do to have a fully functional EV is replace the controller, and battery pack. Actually only half the battery pack. I noticed cells FS recently in the Classified on this forum that would be drop-in replacements, probably at decent cost since they are presumably used.


We have a timeline for construction so we can test her theory in time for the Science fair. Have to be done by December.
wow.... done by december!
you basically will HAVE to buy a mostly predone EV to meet that deadline. It will be a push even then!



Further on that if you don't mind me asking why you tearing it apart?
because nobody so far has had a need for a *nearly functional* DIY swift. Even though I would think many people consider the Swift utilitarian.... few consider it beautiful, and don't really want to drive one around no matter how cool it is as an EV.


Looked at your website and there is some awesome information there. Actually your Li-ion battery got me rethinking the size and structure we are thinking of using.

I also looked at the Nissan Leaf I think the cellular structure of that makes for swappable parts without completely tossing the battery. Thinking we might build our packs in a similar way 2p20s and then parallel sub groups to voltage then those serial to amperage.
if you build packs from parts of Leaf packs.... you have a significant challenge in fabrication of your parallel and series strings with all those small cells as well as what to use for a BMS and charger. If you are looking for the SIMPLEST re-build, I would highly suggest not changing the basic design at all and focus on simple replacement of the controller and large format (100ah) prismatic cells.

really, the only chance you have of meeting a december completion target.

Shipping a whole car across the country cost on the order of $800 bucks, and I'll charge you LESS than retail cost of the major parts, for a pre-fabricated EV almost ready to roll.
 

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Discussion Starter #6
if we can come to grips on money, we can arrange shipping and get it to you as is.... only thing you'd have to do to have a fully functional EV is replace the controller, and battery pack. Actually only half the battery pack. I noticed cells FS recently in the Classified on this forum that would be drop-in replacements, probably at decent cost since they are presumably

if you build packs from parts of Leaf packs.... you have a significant challenge in fabrication of your parallel and series strings with all those small cells as well as what to use for a BMS and charger. If you are looking for the SIMPLEST re-build, I would highly suggest not changing the basic design at all and focus on simple replacement of the controller and large format (100ah) prismatic cells.

Shipping a whole car across the country cost on the order of $800 bucks, and I'll charge you LESS than retail cost of the major parts, for a pre-fabricated EV almost ready to roll.
Money and time are keys. Her science fair project is : can the average family build a usable ev for the average cost of fuel purchased in 3 months. So that being said we don't have a large amount of money to spend.

Now we already have a car, motor, controller, and 18650 batteries are pouring in. So if we go the mostly built route cost is a huge player.

I wasn't planning to use leaf cells per se but I liked the layout format used. Structured sub packets.

Let me know what number your thinking of and lets talk, maybe we can make something workout.
 

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Money and time are keys. Her science fair project is : can the average family build a usable ev for the average cost of fuel purchased in 3 months. So that being said we don't have a large amount of money to spend.
Sounds to me like you REALLY don't need to actually build a car to present this information at a science fair..... Unless you are really committed to design, build, document, and owning/driving the result you should think hard on whether you have the time or money to build a car, especially if you want to have it drivable by December.

I have gone thru all the numbers you are talking about comparing cost to convert and operate a DIY EV compared to the cost of pre-conversion ICE vehicle. The nutshell version is that if gasoline is over about $2.75/gallon, then the amortized cost of batteries (as a 'consumable') plus the actual cost of electricity is about a wash on pure economics.

I'd invite you to spend a hour or so reading thru my build site information for the Swift, link is below in my sig, and THEN let's talk about how you want to proceed after you get a better idea of the cost and time to convert as well as operate an EV.
 

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Discussion Starter #9
Sounds to me like you REALLY don't need to actually build a car to present this information at a science fair..... Unless you are really committed to design, build, document, and owning/driving the result you should think hard on whether you have the time or money to build a car, especially if you want to have it drivable by December.
To clarify its end of December, which isn't much better I know. She is fully dedicated to making this happen. Moreover it is a goal driven factor for her so she can grow this project by adding in further steps down the road.
Building and driving the car go directly to her core idea of the average person/family. She can do technical research for weeks certainly and in doing so validate the possibility but she dead set on doing it and proving it. She is the first kid in her school to go to nationals for science in years and she intends to do better this year.

I have gone thru all the numbers you are talking about comparing cost to convert and operate a DIY EV compared to the cost of pre-conversion ICE vehicle. The nutshell version is that if gasoline is over about $2.75/gallon, then the amortized cost of batteries (as a 'consumable') plus the actual cost of electricity is about a wash on pure economics.

I'd invite you to spend a hour or so reading thru my build site information for the Swift, link is below in my sig, and THEN let's talk about how you want to proceed after you get a better idea of the cost and time to convert as well as operate an EV.
Thanks for the perspective on costs. I have and am currently using your swift build as a sounding for what we are doing.

Understand that I accept the overbearing difficulty in play here but we are committed to completion. With my work schedule and local assistance I think it is possible. I might not sleep for the next 6 weeks but so be it. (she wont either lol)
 

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As far as that Science Project is concerned - the answer is NO!

An EV conversion will cost MORE than and be less useful than simply buying a used production EV

EV conversion should be thought of as more like "Hot Rodding" than "saving money"
 

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To be honest, you could do an EV conversion in a weekend if you were prepared and everything went perfectly. Probably not all the bits and bobs, but, engine out, motor and battery in, driveable-ish, yeah.

But a first timer wouldn't be, and it won't.

As to the cost... I'm probably the sketchiest pennypincher around, and I'm doubting you could do it for the cost you want. You may be interested in Damien's $1000 (well, 1000 euro) conversion series. Which includes the cost of the donor vehicle (that smelled like a sheep's latrine). He's extremely well connected in the EV world and can get deals unavailable to most of us. I'm doubting you could outperform him.

If you want to save costs, you generally have to wait for or find good deals.

You say you'll use a 10s 20p battery of 18650s. That's only 1.6 kwh of energy. You want 50 mile range. You'll probably use 250watt-hours per mile. You've got about 7 miles of range.

You're using a geo metro. Ugh. For all the time, money, and effort you're putting into this, why not pick a car you'd actually want to drive at the end of it all?

Wanting and needing it to be done does not mean it can be done. Positive attitude has its limits.

Regardless, keep us posted and good luck. I hope you're successful.
 

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Discussion Starter #12
To be honest, you could do an EV conversion in a weekend if you were prepared and everything went perfectly. Probably not all the bits and bobs, but, engine out, motor and battery in, driveable-ish, yeah.

But a first timer wouldn't be, and it won't.


As to the cost... I'm probably the sketchiest pennypincher around, and I'm doubting you could do it for the cost you want. You may be interested in Damien's $1000 (well, 1000 euro) conversion series. Which includes the cost of the donor vehicle (that smelled like a sheep's latrine). He's extremely well connected in the EV world and can get deals unavailable to most of us. I'm doubting you could outperform him.

If you want to save costs, you generally have to wait for or find good deals.
Your right costs are a big player. car we have, motor was free, batteries are mostly free. using those factors and patience on parts we started looking for months ago. We started collecting parts a while back when we planned to do this using a ford explorer 4wd. But for what it is worth while we do want to succeed failure is always an option.

You say you'll use a 10s 20p battery of 18650s. That's only 1.6 kwh of energy. You want 50 mile range. You'll probably use 250watt-hours per mile. You've got about 7 miles of range.
Your right but that 10s20p is a module of the whole battery im shooting for 144v so we would use 4s2p of those modules to get our entire pack. Which "I think" is sufficent.

You're using a geo metro. Ugh. For all the time, money, and effort you're putting into this, why not pick a car you'd actually want to drive at the end of it all?
lol your right it is not a glorious car. But price was right and it is for a science project. Moreover i was wrong it is a geo prrizm not metro. Girl who listed that car had it listed as geo metro and I posted this idea before I acquired and honestly glossed over that after the fact. My daughter was happier since it was a 4 door not 2. Since the deal was so good I actually made money based on selling my ford and buying this.

Wanting and needing it to be done does not mean it can be done. Positive attitude has its limits.

Regardless, keep us posted and good luck. I hope you're successful.
Thanks your right positive energy only goes so far. But failure is a result and we are willing to try.

I wanted to say thank you independent of the other portions of this. You are the first person that tempered your response as difficult but plausible without the sky is falling mentality. I think we need to encourage and be realistic not just negate ideas.
 

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I might not sleep for the next 6 weeks but so be it. (she wont either lol)
.... I will re-iterate... quickest way to meet your project goals is:
- buy my '97 Swift, en toto
- replace controller
- add whatever batteries/charger you want, and you are done.

everything in the Swift is configured for 120v DC pack (charger and dc-dc) so if you replace with 100ah LiFePO4 like CALB it would be a drop-in solution and you need to replace only the controller. If you already have a bunch other other batteries, go ahead and concentrate on building up your pack with them, add your BMS and charger to match. You would not have to sweat any of the rest of the conversion other than the batteries, charger, controller.

I will work up a cost based on 'used' prices for all the major pieces of value I would otherwise part out, and you will save about 150 hours of labor because the rest of the car it literally ready to go.

... I'd really love to see all this stuff go to a good home, and see the eSwift live another life. The Swift is not 'pretty', but it is VERY practical. I'm perfectly willing to give you a great deal on all the components and basically give you all my labor in putting it together. All it will cost you is 'used' cost for motor, dc-dc, transmission adaptor and a few of the other major parts I would otherwise part out.

contact me directly Dan at EnviroKarma.org and I will work up a price tonite after work.....
 

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But for what it is worth while we do want to succeed failure is always an option.
I think some people also forget that a highschooler with parental help has a hell of a lot more free time than an average adult. Turn off the TV/Netflix and put all those hours into building a car, you get a car done pretty quick.

So many people say things about various hobbies like "I could never do that" or "Sure would be nice to have that much time on my hands" or "I can't believe you spend so much time on that". And if they're a little smarmy about it, the first thing I ask them - a bit disingenuously as if I'm changing the subject - is if they've seen anything interesting on reality TV recently, or what kinds of shows they like to watch. Most people blah blah blah about all their favorite outrageous programs. I'll let them babble a bit and then cut in with "Yeah, mhm, yeah, oh, mhm. Well imagine how much you could get done if you weren't wasting your life with that bullshit."

The thing I would keep in mind is, if you knew ahead of time that you'd blow your deadline, would you behave any differently? Would it still be a worthwhile pursuit? Having a goal is great, but, if there would be a large amount of frustration or a feeling of it all being for nothing if the project doesn't get done... I'd pick a different project, because while I think you're very likely to succeed if you stick with it, you're somewhat likelier to fail in terms of a 6 week build window.

Your right but that 10s20p is a module of the whole battery im shooting for 144v so we would use 4s2p of those modules to get our entire pack. Which "I think" is sufficent.
This is an antiquated method, that I think only a handful of EVers ever succeeded with (like, 2-5). 18650s are popular for E-bike builds, but at car scale, no one seems to ever finish.

I (used to) get my 18650s for free, and I have spare time to disassemble them, and even then I don't know that I'd recommend anyone else pursue it. But I'm cheap and I think I've collected enough so far, (several thousand).

I can probably give you some advice on the 18650 route. What's your strategy there? Where are the cells coming from, how are you testing them, how are you assembling them (construction-wise)?

If you need to order parts from China, it might take you 3-4 weeks to get them, which makes a hell of a crunch time even if you order now. US sources will be 2-3x the cost. So, lay it all out now and plan ahead.

lol your right it is not a glorious car.
It's a piece of shit. It's the stereotypical cheap crappy car. People will look at you and say "This person couldn't afford a bus pass" or "This person must not have legs, because I would rather walk than drive that."



If it's brown people would mistake it for someone dumping turd onto a skateboard.

There are plenty of cheap, crappy, old, but still cool cars that you can look at at the end of your project and say "I built this and I want people to see me driving it".

A Prizm has no character. It evokes no emotion. It's a plastic garden shed that rolls.

It's really only acceptable for a teenager to drive, as a "This is all I'm allowed" vehicle, so, I guess you're on track there. But, for the same price, really, almost anything else would be easier to have some pride in.

...

What's your plans for a controller, and have you bought it already?

AC Compressor/Treadmill motor - A great add-on. Leave space for it but ignore it.

Power steering pump - Skip it. Add it later.

Brake booster - What's powering the vacuum? Have you got one yet?

Charger - Sketchy, but you can just use a power cord and a correctly-sized capacitor to charge, I think. Info in one of Damien's videos. For a temp setup, a variac will work. Maybe kind of plan on that until you get it rolling.

BMS - Skip it. You're only 10S. Buy 10 tiny 3-digit voltmeters on Ebay for like $1.50 each, mount 'em on a panel, and just directly observe each module's voltage. If you notice they get out of swing, you'll know you have to manually charge them or stop driving. Under normal conditions, a balanced-built pack should stay balanced. Gradual differences accumulating over time are what results in imbalance. If you just keep an eye on it and top balance it once in a while, you'll be fine. She'll be keeping a finger on the pulse of her POS and know every bolt and wire anyway, should be fine.

Adapater plate (what joins motor to trans) - What's your plan?

Again, it's doable, but you gotta hammer out the details ASAP or you'll blow your budget or deadline.
 

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Curiosity Bump.

The OP's deadline was the end of December.

Any updates? Did this build ever proceed, and if so, did it get finished on time?
 

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Curiosity Bump.

The OP's deadline was the end of December.

Any updates? Did this build ever proceed, and if so, did it get finished on time?
I volunteered shipping my entire (completed) Suzuki eSwift which only needs the controller replaced, and a fresh set of batteries..... but I think the OP wanted everything for free.

As we are all aware, you can only have 2 out of 3 goals of good, fast, and inexpensive when attempting DIY ev.....
 

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Money and time are keys. Her science fair project is : can the average family build a usable ev for the average cost of fuel purchased in 3 months.
The answer there I'm sure you've discovered is: no, you cannot convert a car for less than $1000.

The cost to convert a ICE vehicle to an EV, presumably with 'decent' performance and minimal 40-50 mile range will be somewhere between $12k for all new parts and batteries for a DC build with 120v x 100ah Lithium pack.... down to maybe $8k if you scrounge used parts but stick to new batteries... MAYBE down to $5k if you cobble together all used parts.

plus the cost of donor car, and a minimum of 100-150 hours of actual labor.

Interestly..... if you keep an eye in the classified section of this forum.... if your timing is good, there have been several COMPLETED conversions for sale in the $3k-$5k range, usually missing only one part or needing a new battery pack. (like my eSwift missing a controller and half a battery pack at this point).
 

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Discussion Starter #18
Sorry I haven't popped back on to say how it went down. We got it all done there were a couple hiccups but got the project turned in and she won first place at the science fair.

Couple things I noticed there was a couple points of comment about doing it for less than $1,000 we were going to do it for less than three months of fuel which was about $3,000. Based on national average research for our state. Our final price not including the car was right about 1300. I have a few improvements to make that will push that up a bit but not immensely.

We skipped a few things air conditioner, power steering, and brake booster I'm working on those now hope to have it done before she goes to county or at least the Regionals. All will be fed from the same aux motor. Except the the brake booster it is a separate micro vacuum.

Some specific questions asked about a plate for adapter made that it off like it was part of the original engine mounted it to the original engines motor mounts.

I welded the clutch disc to a two-part connector welded the other part to the stub shaft on the motor. Shimmed everything and then bolted down. Rock solid and seems to have no discernible deflection.

18650 cells galore came from a local e scrap shop. My daughter was very diligent in charging them. Now that the modules are built charging is the issue. I'm looking at building a variant bonn charger with a few trim pots to set the amps and volts.

Also want to improve the start sequence by adding 2 ev200 in to the mix and powering them through the key switch. Main line with pre-charge at aux then the full at on.
 

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Awesome news! Great to hear!

Take lots of pics for us, I'd love to see.

Sorry we couldn't have been more help, but, probably can't be sitting on the internet when you have a car to build. I sit on the internet and my car's taken 8 months to not build :p. 3 months is a crazy deadline. Good for her!

How many 18650s did she end up using?

What did the range end up being?

$1000/month is "average" gas use for your state? Whaaaaaaa? $250/week? That's a full tank on a small car every day. Average. ... ? That can't be. Which state drives 300 miles a day average?
 

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Discussion Starter #20 (Edited)
Awesome news! Great to hear!

Take lots of pics for us, I'd love to see.

Sorry we couldn't have been more help, but, probably can't be sitting on the internet when you have a car to build. I sit on the internet and my car's taken 8 months to not build
. 3 months is a crazy deadline. Good for her!

How many 18650s did she end up using?

What did the range end up being?

$1000/month is "average" gas use for your state? Whaaaaaaa? $250/week? That's a full tank on a small car every day. Average. ... ? That can't be. Which state drives 300 miles a day average?
So your right I asked a few questions and then ghosted no time for forums. I will get pics up soon we only have a few million it seems. We are doing an animation for regionals of the build process.

We used 1600 batteries. And are looking to add another 400

So we got right at 45 miles diving conservative and not in traffic or stop lights etc. And had a little left so we said 50 miles. We intend to do a real "road" test soon.

Honestly I didn't double check her fuel research. And while it seems excessive imo it might be accurate. At 2.40 a gallon and Alabama with a lot of big trucks. I'll double check her research.
 
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