A completely new sort of EV

[ShadeTreeMech]

I may need a reality check for my aspirations after writing this, but I hope there are those among ya'll that are a bit more versed in EV and the limitations and costs thereof than I am.

I have a straight 91 Explorer my wife and I love to death. It got horrid fuel economy, but in our rural neck of the world has proven itself very useful and a lot of fun. When the engine quit I at first intended to refit it with a diesel engine for better economy, but that is a bit pricey and complicated. I then thought why not make it electric? So now I have my set of goals and a few questions for ya'll to help me realign.

I want the final project to be able to burn off the tires if need be while being capable of decent economy. I don't want it to go faster than 60mph, but it needs at least to reach 50 due to local considerations. I'd like to keep it under $3000 and am capable of doing the majority of the labor. Considering the large vacancy that will emerge under the hood, I am considering installing a small generator to supplement the range if needed, or maybe additional batteries. And as it is a 4x4, which I want to keep, I was considering going for a pair of smaller motors which I can engage seperately for additional power/traction instead of using the transmission and transfer case. It currently has a burned out auto tranny, which I understand is not a great idea with the electric motor anyway.

Is it possible to attach a electric motor directly to the drivelines? Would it be more cost effective to keep the transfer case and use just one larger motor? Do I need a transmission or would an industrial gearbox do the trick? Would putting a 5 speed help with range and power compared to a static gear ratio? I read the 72 volts is as high as you want to go for the controller boxes before it gets pricey, so could I use 2 in tandem to run 2 seperate motors?

In my area there is only 1 electric car in use to my knowledge, and it is rather puny. There is a local folk gathering during the summer and there is a burnout competition in a parking lot, which is just for fun. I think it would be cool to enter it in an efficient EV that used to be one of the icons of the gas guzzling SUVs, a first year Ford Explorer. Imagine their faces if I were to brun the tires off with and electric motor. Most folks out here think electric cars are gutless oversized golf carts and I'd like to help change a few minds. And I'd like to still be able to go off roading in it, especially considering the abundance of opprotunity to do so in the Ozark Mountains.

How should I best go about this? What budget should I plan on? What is it likely to cost? Help me out with my dream.

[Ryland]

Is your $3,000 budget for the motor, the controller, or the battery?
My 1,400 pound "golf cart" based EV uses $900 worth of golf cart batteries to get 48 volts and it uses them to their limits at times.

In my mind, if you have to ask if it's possible to do for that amount, then it's not, care to prove me wrong? I'm trying to build a $1,500 electric motorcycle and am going to cut it close.
I'm not sure why you need 4 wheel drive, I've taken my civic off road, with a trailer and never had an issue, it will go places that my parents Ford Ranger gets stuck.

[vpoppv]

I applaud your efforts to want to make an EV. There should be more of you around, as the world would be a better place. With research and time, you will be able to answer all your questions. At first glance, you are faced with a couple challenges. In my humble opinion, your biggest obstacle is your vehicle choice. One method that can be helpful in deciding on what vehicle to convert is that if it is a big, bulky, fuel inefficient vehicle to begin with, it will be a big, bulky, hard to power vehicle as an electric. While an electric motor is way more efficient than an internal combustion engine, you still need to consider basic physics: the bigger and heavier, the more energy it will take to move it. Batteries can only hold so much energy......

[jamminjimmy]

I'm definitely not an expert with EV's.... But is there any EV that can turn tires???? Or even one that has enough energy to turn tires, and still have some left to drive home with? I don't know, but i haven't heard of any.....

[Ryland]

You might be better off selling your SUV for parts or scrap and buying smaller vehicle to do this with.
Did I miss where you said how far you need to go? if it's just 3 miles like Vpoppv then you might be able to pull it off if you can get alot of free parts, or parts at scrap price, but you are going to need a big motor for a vehicle of that size.

[bennelson]

Originally Posted by jamminjimmy

I But is there any EV that can turn tires???? Or even one that has enough energy to turn tires,

Yes, here's two:
Tesla Roadster. - More than your budget.
White Zombie - A 1972 Datsun

One of the biggest things I always see with people interested in electric conversions is that they have unrealistic expectations. They think it will cost less, go farther, go faster, and have better acceleration than it actually will.

Also, electric motors really do kick gasoline engine's butts! It is far superior technology, hands down.
The issue is how much energy can be stored in your fuel. (At what weight and size = "energy density". As well as what price?)

Gasoline has an AMAZING AMOUNT OF ENERGY IN IT!

I think a truck like this could have some really neat potential as a hybrid. A four-wheel drive system could be setup with an electric motor on one set of wheels and the gasoline engine going to the other.
Otherwise, an electric motor powers the wheels, with energy from the batteries, and topped off on the fly from a generator. (Plug-in serial-hybrid - Chevy Volt style.)

If you need to go 60 mph, you will need higher than 72V. Check out the Open Revolt controllers. They really work well.

[Ryland]

Even if your batteries are free (they have a scrap value of $7-12 each) you still need cables and lugs to make your own cables to connect batteries together tend to be $4 each or more and you need two per battery, 6 volt batteries tend to hold up better then 12 volt batteries but for a high voltage system you would need alot of 6 volt batteries.
Then you need the copper cables at a few bucks per foot, someone with a $2,000 crimper to crimp the lugs to the cables, battery boxes, a controller (more lugs and cable to connect to the controller and motor) you need a motor, but lets say you can get a motor for scrap price, scrap price for motors is around 25 cents per pound and for a vehicle that size you might end up with a 100+ pound motor, but who is going to sell you a motor for the price of scrap?
Then you need controller, you can make your own, or buy one, ones that work for a high end golf cart tend to be in the $400-600 range and for a full size electric car $600-$2,000? you could spend more if you want to burn tires.
of course all of this is assuming that you are the kind of person that can live with a very low income, who grows and finds food and can make a $100 car last many years.

[TomEV]

While this kit is probably not under $3,000, here is an idea for you - motor as part of the rear drive shaft.

S10 EMIS Project

The right hand picture in the URL above shows how they installed the motor.

[ShadeTreeMech]

Tom EV, thank you for the link. That is kinda what i was envisioning, a motor attached to the frame via steel trusses.

To help me determine the feasibilty, I'm playing with some math now. The truck originally came with a 155 hp (116 kW) engine. That being the standard, I just need to know what the equivalent electric motor would run. It may be made easier if I halved the requirements and split it between 2 electric motors that need not run at the same time.

Something else to consider is with that amount of horsepower I was capable of well over 75 mph, which is much faster than I intend to go with the EV incarnation. However, I'll be adding weight in the form of batteries, so the 116kW figure may need to stand.

Just for giggles, Im curious to know the weight of battery packs and HP figures for a few of these EVs on here. It seems I saw a figure for a 90 HP motor mentioned here somewhere, and that alone would likely do it. But other than that, i haven't anything to go on. I did read 23 pages of the DIY motor controller thread before my eyes started to bug out, but I learned a bit. What would prevent me from viewing this as 2 seperate EVs sharing the same frame?

I realize the potential for weighing a lot is great, hence why I'm considering having a generator for helping with the range. There's one with a 2800 watt rating on ebay for $400, and yes I realize that is far short of the 116kW I would need at max. But if I were to depend on it as simply a way to extend range, and be able to recharge whenever I stop, it could do it while burning much less fuel than the 15 mpg I was getting.

Why the Ford Explorer? For one, I already own it. I know that the body is solid and the rear diff especially is lusted after for its strength among 4x4 enthusiasts. And why do I need 4wd? I wish you could have been with me after we had a heavy rain. My dirt road was impassible by a car, but the higher stance and extra traction got me home. 90% of the time I don't need it, but the 10% of the time I do need it, it's indespensible. While it may be very bricklike, it also has a ton of room for batteries, generators, kids, dogs, camping gear, etc.

But I suppose the biggest thing is that it hasn't been done by a DIY sort that I know of yet. And while a smaller car being made to an EV is more practical, an SUV made to an EV would turn more heads in this neck of the woods. I may have to do this in stages. If I can get it to putt putt it's way to town for the time being until I can get a stronger (or second) motor, so be it. I'm confident it's possible, but there are too many unanswered questions in my head right now to know where to begin. From what I'm told about electric motors, torque is not a problem. So it may be more feasible than we think. I know in the UK they have electric milk trucks, and I'm sure they are quite heavy. But they manage to use them somehow.

I know it's a crazy idea. But so was putting vehicles to be assembled on a conveyor belt instead of on the floor, and it seemed to serve Henry Ford alright.

[ShadeTreeMech]

bennelson, you've also thought of something I considered, which was adding a electric motor to one of the axles. The front axles can be easily disengaged from the drivetrain, so I thought replacing the transfer case with an electric motor woudn't be a bad idea.

I'm still not sure how I want to go about this yet, but as it stands, the engine and transmission are both in need of replacement, so to make it a hybrid could be more expensive than making it more electric with a generator assist.