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Discussion Starter · #1 ·
Hello,
I am looking to abandon gas entirely and build a commuter car. I have been living fully offgrid for 6+ years and can build a wide range of lithium batteries myself.
Its time I left gas behind. I need help determining the best setup for a simple commuter as far as motor, controller, subsystems, charging. I am building the battery myself. It will be capable of 300a Continuous, at whatever voltage is needed, using LiFePO4 Chemistry Grade A cells and an appropriate BMS.

My parameters so far are as follows:
Donor car types being considered (Honda Insight lightened up, VW bug/beetle with a lot of fiberglass replacement parts, GEO metro stripped lightened, Geo Tracker lightened, etc.) Simpler onboard systems the better. (Crank windows, manual everything, as light as possible, easy to interface with signals and breaks. Retain power boosted breaking if possible)
AC not required. I'll live.
Range needed = 55-65 miles one way
Top Speed = 60-70mph
Acceleration - Not important - Turtle slow is fine, just need a decent cruising speed for my commute. Slow lane get me there, type car.
Voltage = 96V - 144v DC system if possible.
Motor = Preferably AC motor setup
Battery = Self built LiFePO4 300ah - 3x 100ah Packs at whatever config is needed for motor voltage requirements.
Terrain - Florida FLAT - No hills
Nice to have a radio, personal fan, 12v accessory plugs
Want to have ability to tie a solar array to the car for charging.

I have space at work and at home for a 2-4kW solar array to charge with.
Would also like the option to Generator charge @ 110v with a smaller inverter Generator if needed. (Emergency use only if stranded)

I need help determining a motor setup that is as LOW COST as is possible, but I am willing to spend 4-5000$ on the battery, 4-5000 on Motor and controller setup, and 2000$ ish on my donor car. Initially.

I will upgrade and extend range as I go.

As I am already spending 10,000$ a year in gas for my ford F-150 as it is, I'd prefer to park her, and use her only for trailer pulling occasionally, and commute full time in an EV of my own make/design. A 15,000$ build is what I am expecting, with 10,000$-12,000$ just to get started.

But, I am new at conversion, and need HELP to get to the finish line on this one without screwing anything up.

Particularly, I need help determining a decent motor and control setup that is both hearty, and can be had for my 5000$ budget for that part.
I need to be able to cruise for almost an hour at minimal highway speeds to get to and from work. If I need to add cooling, so be it.

Batteries and charging I can handle myself. Batrium can deal with a pack of any series width, and I know it well. I also know how to build and size solar array's/stations to handle the charging. Finding/making the right gear to get the pack charging optimally at the needed voltage will be a challenge, but I can split the pack down smaller for charging with solenoid disconnects if needed. So I would like to stay within multiples of 48vdc to use off the shelf MPPT controllers and chargers to get recharged.

Please let me know what your thoughts are. I am hoping to build the car this year, and I understand this is not an easy project.

I have the time and energy to get it done. But not the full technical understanding of the motor and drive components to guarantee i can reach my desired speeds and range.

Thank you for your time/help in advance!

Steve
 

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Buy a used (best) or wrecked Nissan Leaf. Well inside your budget.

If you must do a conversion, vs just driving the damned Leaf, pick a conversion target the Leaf motor and gearbox plays nicely with and where its batteries can get crammed in.

Charge off your solar inverter at 120V or 240V.
 

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Discussion Starter · #3 ·
Buy a used (best) or wrecked Nissan Leaf. Well inside your budget.

If you must do a conversion, vs just driving the damned Leaf, pick a conversion target the Leaf motor and gearbox plays nicely with and where its batteries can get crammed in.

Charge off your solar inverter at 120V or 240V.
Come to think of it, I have a friend with a 2014 leaf with a dead battery. He would likely sell to me cheap.

Can I simply build a LifePO4 battery and integrate it in place of the original battery?

I would assume so as long as I am taking care of recharging it myself.

Thank you.
 

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Discussion Starter · #5 ·
yupp

perfect, though "in place of the original battery" is a lot harder than you'd think
Thank you for that idea.
Leaf battery cells are very familiar to me. As I have built a large powerwall with Gen2 Leaf cells before. Several actually. So I am familiar with the cell.
IF I can simply evade/bypass the built in BMS/Charging entirely, and build my own... As long as the car will recognize that a pack of the proper voltage and available ampacity is in place and drive on it. I should be ok.

If so...

That clearly sounds like the path of least resistance in this scenario to me. :)
 

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Doesn't looks as easy as it sounds to interface.
Looking at a conversion still. Preferably at a lower voltage.
Details about why it was not as easy?

Converted a sandrail to EV, so I will help if I can. What is your vehicle? What are your charger and evcc? What is your BMS? What are your battery configuration and individual cell specs?
 

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this sounds like a contradiction

Voltage = 96V - 144v DC system if possible.
Motor = Preferably AC motor setup

AC motors usually run at higher voltages

by far the best bang for the buck is either the Toyota Prius Second Gen (2004-09) or Third Gen (2010-15) Option, as you can buy the front wheel drive motor/transaxle and Inverter (inverter/converter/charger all in one box) for $250 bucks then all you need is a controller circuit board for additional $350 see this link Toyota Prius™ Gen2 inverter controller - community edition

as we speak the man himself Johannes Hübner (the man who revere engineered the AC motor inverter technology) is converting an Audi for his friend using the Second Gen Toyota Prius, you can follow his progress on his YouTube Channel, honestly it does not get any better than this


 

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Discussion Starter · #12 ·
Details about why it was not as easy?

Converted a sandrail to EV, so I will help if I can. What is your vehicle? What are your charger and evcc? What is your BMS? What are your battery configuration and individual cell specs?
I am responding to you as a Manx Electric DIY has actually been my dream for many years.
Why not as easy?... Well here is my thinking.
The leaf is a good candidate, but. I am trying to keep this simple, and use NEW lithium in my build that is widely available.
The leaf cells are NOT widely available in good condition and totally unavailable new.
So if I want to swap to a self built LiFePO4 pack, it will take up the original location, and my backseat. The Internal BMS won't be easily adaptable. The Canbus is an issue. Etc.
Meaning my driving experience is always going to be on used lithium, driving a car on borrowed time.

I would prefer to build this with a new motor and controller, preferably a kit or parts known to produce reliable results.
Also, I would prefer that the lithium is new, and can be charged by solar. I live offgrid in a Class A with a 1000ah 58.8v LiFePo4 Pack running my home electric. Solar on the roof to charge.
There will have to be a solar charge array and charge controller specifically built for me to charge my car with.
However, I have access to an unlimited supply of SunPower 430watt 72v Panels @ 150$ ea. So these can be built cheaply.
Also, I would like a car with simple systems. (Hand crank windows, mechanical speedo, Manual door locks, etc. If it even has those things) Manx VW build, Geo Metro, Honda Insight, Etc.

I Repair and service RVs for a living and have access to every automotive machine and tool under the sun. (Lifts, Impacts, Welders, Plasma cutters, Tire machine, etc)
Plus my boss owns a race team. So I am quite certain that I can get an adapter plate and spline coupler made for any motor / trans setup. As well as build out any battery framing or boxed locations needed.

The Way-Off Grid this is my Youtube channel. You will see some of my previous builds there.

I am typically using a High Amp Daly BMS and Victron Shunt, or Batrium to watch my packs.
As I'll be using strictly solar at one end, and plugging in at the other, I'll need an EVCC onboard and charger at work, and a custom solar charge control setup at the other end or built into the car.
This is a multiyear project for me, and I will likely own this car to the end of my life. Upgrading it as I go.
Again, my parameters are:
AC not required. I'll live.
Range needed = 55-65 miles one way
Top Speed = 60-70mph
Acceleration = Not important - Turtle slow is fine, just need a decent cruising speed for my commute. Slow lane get me there, type car.
Voltage = 96v - 144v DC system if possible I'll go higher voltage if thats what it takes. But as low as possible. Safer is better.
Motor = Preferably AC motor setup, but If a good DC motor setup can do the 60 miles one way trip without overheating, that works too.
Terrain = Florida FLAT - No hills
Nice to have a radio, personal fan, 12v accessory plugs
I'll build whatever battery is needed to power the car. Preferably with LiFePO4, Grade A cells, Brand New, Under Fixture, with Solid Copper Interconnects.
But I want to use NEW lithium to build it. Not try and obtain a used pack that cannot be purchased from the manufacturer.
As much as I like the leaf cells.
I also want to use a setup that does not require the use of a motor that may become unavailable at some point. Such as those from OEM electric cars.
Prefer to use a motor setup that allows me to change over the motor to something else later on if I desire an upgrade.
Being setup as a general use mounting platform, is actually my plan for the car. The motor should be anything that fits into the given space.
Also, I have x3 3D Printers, for fabricating mounting and protective enclosures.
I can draw and print just about anything. My Thingiverse Profile shows my level of ability for prototyping and design.

This is a serious project, that I am looking for serious suggestions, recommendations, and technical information and assistance with.

As you can see, I share all my designs with the world for free, and give credit to any and all contributors to my projects.

Any and all assistance is most appreciated, especially would like to see your Sandrail Build.
The manx build in my mind is likely far more than I can afford, but something in between that and a beater bug build should serve me quite well :)

Attached are some of my other battery builds. Including the Pack I currently live on.

Thanks again to all of you for the replies!
 

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Converting a car to run on electric is quite a challenge; I would only suggest it to someone who has it on their "bucket list" of things that their life would not be complete without having done. It sounds like you have a good background in batteries, so I think you are already way ahead of most of the people who wander in here with wild dreams.

I think your idea of going light-weight and as aerodynamic as possible is a good one, especially if you want to drive on the freeway. My pickup uses more power than I thought, and I hardly drive it over 45mph.

Getting a broken Leaf and stripping it for parts would likely be the cheapest way to go for the motor and controller. Thunderstruck makes a control unit. VCU for UQM Motor It does mean you will need higher voltage. I thought about using a Leaf motor adapted to my transmission, but decided on a hyper 9 and a pre-made adapter plate solution to keep my project moving along.

Charging directly from solar is an interesting idea, but youd probably want a standard charger onboard anyway to charge when away from home, right? It seems like with the added cost and complexity (charge controllers and high amp contactors) you might be better off just charging through an inverter.
 

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The obvious choice here for low voltage AC is a hyper 9, it would exceed all your requirements if coupled with 5 Tesla modules. LifePo4 is fine, but used OEM batteries are generally better and cheaper. In a car conversion, you'll want a BMS with more functionality than something like a daly BMS (controlling contactors, etc). If you're using tesla modules, I'll plug the SimpBMS: SimpBMS Tesla Battery Management System For Tesla Model S/X Battery Modules | eBay

The leaf motor is a good suggestion as well, if you go that route I'd couple it with either leaf cells or 2 chevy volt packs. This route would likely be a little cheaper but also more complex. I don't think it's as easy to reuse all of the leaf stuff as remy_martian indicates, although I may be wrong. In particular I don't think anyone's cracked the Leaf BMS. The leaf motor/inverter stack is very popular and has been "figured out" for sure though.

If the goal is to save money on gas and you want to start driving it as soon as possible, I think a hyper 9-based conversion would get you on the road sooner than the Leaf route.

Your performance demand and price expectations are very reasonable though, so I'd expect that you'll be able to build something that fits your needs quite well.
 

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As you plan for long ownership of the car, and have noted wanting to ensure parts are available in the future, perhaps something like a Geo Metro would not be the best choice. It lacks curb appeal, and since it doesn't seem likely to become collectible at any point, mechanical parts availability may dry up sooner than one would want. If you pick something that is going to have a solid aftermarket following you will be at less risk for that.
Maybe not the best example, but at least flashier would be something like a first gen MR2. My favorite of the many cars I've owned. Becoming quite collectible, I just hope the parts stay available.
 

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this sounds like a contradiction

Voltage = 96V - 144v DC system if possible.
Motor = Preferably AC motor setup

AC motors usually run at higher voltages
There is no contradiction here. Production EV motors are all AC, and all run at higher voltages. Industrial and aftermarket motors are available in AC or DC at just about any voltage you might want.
 

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Hello,
I am looking to abandon gas entirely and build a commuter car. I have been living fully offgrid for 6+ years and can build a wide range of lithium batteries myself.
Its time I left gas behind. I need help determining the best setup for a simple commuter as far as motor, controller, subsystems, charging. I am building the battery myself. It will be capable of 300a Continuous, at whatever voltage is needed, using LiFePO4 Chemistry Grade A cells and an appropriate BMS.

My parameters so far are as follows:
Donor car types being considered (Honda Insight lightened up, VW bug/beetle with a lot of fiberglass replacement parts, GEO metro stripped lightened, Geo Tracker lightened, etc.) Simpler onboard systems the better. (Crank windows, manual everything, as light as possible, easy to interface with signals and breaks. Retain power boosted breaking if possible)
AC not required. I'll live.
Range needed = 55-65 miles one way
Top Speed = 60-70mph
Acceleration - Not important - Turtle slow is fine, just need a decent cruising speed for my commute. Slow lane get me there, type car.
Voltage = 96V - 144v DC system if possible.
Motor = Preferably AC motor setup
Battery = Self built LiFePO4 300ah - 3x 100ah Packs at whatever config is needed for motor voltage requirements.
Terrain - Florida FLAT - No hills
Nice to have a radio, personal fan, 12v accessory plugs
Want to have ability to tie a solar array to the car for charging.

I have space at work and at home for a 2-4kW solar array to charge with.
Would also like the option to Generator charge @ 110v with a smaller inverter Generator if needed. (Emergency use only if stranded)

I need help determining a motor setup that is as LOW COST as is possible, but I am willing to spend 4-5000$ on the battery, 4-5000 on Motor and controller setup, and 2000$ ish on my donor car. Initially.

I will upgrade and extend range as I go.

As I am already spending 10,000$ a year in gas for my ford F-150 as it is, I'd prefer to park her, and use her only for trailer pulling occasionally, and commute full time in an EV of my own make/design. A 15,000$ build is what I am expecting, with 10,000$-12,000$ just to get started.

But, I am new at conversion, and need HELP to get to the finish line on this one without screwing anything up.

Particularly, I need help determining a decent motor and control setup that is both hearty, and can be had for my 5000$ budget for that part.
I need to be able to cruise for almost an hour at minimal highway speeds to get to and from work. If I need to add cooling, so be it.

Batteries and charging I can handle myself. Batrium can deal with a pack of any series width, and I know it well. I also know how to build and size solar array's/stations to handle the charging. Finding/making the right gear to get the pack charging optimally at the needed voltage will be a challenge, but I can split the pack down smaller for charging with solenoid disconnects if needed. So I would like to stay within multiples of 48vdc to use off the shelf MPPT controllers and chargers to get recharged.

Please let me know what your thoughts are. I am hoping to build the car this year, and I understand this is not an easy project.

I have the time and energy to get it done. But not the full technical understanding of the motor and drive components to guarantee i can reach my desired speeds and range.

Thank you for your time/help in advance!

Steve
I just posted a thread in your personal conversations and posted some EV links to have a look. EVAlbum.com is a great place to search what others have done. Converting a VW Manx would be an easy conversion. DC or AC. AC is best and an AC-35 or 50 with a 96 volt 650 amp controller would be fine or the same motor but using the 144v 500amp controller for a higher rpm range but less hp but would still make a very nice conversion that is freeway drivable. The open buggy is not the best in cold weather or wet weather. For overall commuting you should consider a closed vehicle for foul weather comfort.
 

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I just posted a thread in your personal conversations and posted some EV links to have a look. EVAlbum.com is a great place to search what others have done. Converting a VW Manx would be an easy conversion. DC or AC. AC is best and an AC-35 or 50 with a 96 volt 650 amp controller would be fine or the same motor but using the 144v 500amp controller for a higher rpm range but less hp but would still make a very nice conversion that is freeway drivable. The open buggy is not the best in cold weather or wet weather. For overall commuting you should consider a closed vehicle for foul weather comfort.
We used to have a great garage here on DIY but that went away a few years ago. Bummer. Had lots of conversions here. Lost a lot of good people here because of the changes. A few of use still check in from time to time.
 

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Hi
I would suggest using the Leaf - but replacing the motor "Brain" with one of the aftermarket units "thunderstruck??"
This would mean that you had control over the motor
The rest would be up to you - but you don't really need all of the fancy stuff inside the Leaf

The next stage would be to throw away the shell and put the mechanics inside something like my "Device" - but as Onegreenev says that is not the best for all year round driving!
 

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Just fyi, 144v DC will kill/injure you just as efficiently as 400v DC will.

The pros and cons I see with the different voltages (This is just my opinion)

Higher voltage = lower current to do the same work. Lower current means less copper needed for conductors, wires etc. Less heat, less 'load' on inverters etc.
Higher voltage would allow usage of OEM parts, they've had millions in R&D spent on them by the manufacturer, long expected working lifetime etc.
Lower voltage generally means a smaller physical battery, but with the caveat that a smaller battery has less energy to put into driving = Potentially shorter range. That shouldn't be an issue for you though based on what your looking for. A Con of higher voltage is a physically larger battery but the range is usually better overall.
The Warp series motors look flash, but they are essentially just a pretty looking forklift motor. They haven't had millions in R&D spent on them, they don't necessarily have 'proven' long working lifespans, however, that can be somewhat countered by using the forklift motors they are based off as a great working life example.

OEM motors often have the transaxle and gear reduction built in, they are typically very compact and efficient in the space used. A Warp series motor needs to be connected to a gearbox that will probably only use 2, maybe 3 of the 5 gears inside. Changing gears while driving probably needs to retain the clutch and all its complexity (a weak point under the torque of a motor) or unloading the power from the motor, then shift without a clutch. Can be done, but may trash the gearbox over its life. Depending on your choice of conversion vehicle (Rwd in this example), if you could use a transaxle motor in place of the rear drive axle, that would then leave the whole engine bay/tunnel open for batteries, contactors, components etc. Otherwise it'd be a Warp motor sitting where the old engine was, the gearbox, driveshaft, rear axle etc would all still be in place, so finding room for the battery may be more difficult. Point to note that if you had a Warp motor, your likely running a smaller physical battery.
 
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