Jeep Cherokee EV conversion

casm

NAXJA Forum User
Location
Oklahoma
Ran across this while looking for something else: Jeep Cherokee EV conversion. Biodiesel is still the way to go IMHO, but it makes for an interesting read nonetheless.
 
I wonder how it actually drives though... Quiet, yea, but how fast does it accelerate? How long can you drive it before the battery dies, etc.
 
xjj33p3r said:
I wonder how it actually drives though... Quiet, yea, but how fast does it accelerate? How long can you drive it before the battery dies, etc.
Agreed, I wouldn't think it would perform too well considering what the XJ weighs...
 
Fuel costs aside from operating costs?

A 4.0 (assuming a "new" engine @250k/$2500= $0.01/mile) is pretty cheap... typically will need little mechanical repairs throughout it's lifespan.

A KJ (or other) diesel conversion is likely real high$ initially, then at what interval will that puppy need an overhaul (and at what cost?) 300k@$5000= less than $.02 per mile. Biodiesel would help ease that, to some extent.

I wonder how often do those (twenty) 8vdc rascals will need recycling? and at what cost? Same goes for rebuilding the big DC motor.
 
woody said:
Fuel costs aside from operating costs?

What gets me about these things is that none of the people who call them 'environmentally friendly' realise that all they're doing is relocating the vehicle's emissions from the tailpipe to the power station. Interesting conversion, but kind of an odd vehicle to choose for it.

BTW, didn't realise this was a repost... Couldn't find it with a quick search, so just threw it out there.
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I want one powered by a big gyro wheel in the middle like the toy cars I had as a kid. Yank the cord, point it in a likely direction, and vamoose.
 
casm said:
BTW, didn't realise this was a repost... Couldn't find it with a quick search, so just threw it out there.
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Its an old repost....maybe not from this forum...But since I don't frequent JU and can't stand the jerks and Pirate...I would say its a safe guess I saw it here.

Besides....its always good to bring stuff like this up again anyway.
 
Hi everyone,

I'm glad to hear that you found my Jeep Cherokee Electric Vehicle conversion interesting! Although some or all of the questions you raised in this thread so far were probably rhetorical, I'd like to take a moment to respond to them anyway. I do so in the hopes that I can correct any misconceptions you may have about modern Electric Vehicles.

xjj33p3r said:
I wonder how it actually drives though... Quiet, yea, but how fast does it accelerate? How long can you drive it before the battery dies, etc.
As with a gas-powered vehicle, the acceleration times and distance per charge (range) of an EV varies depending on the electrical system installed (i.e. AC vs. DC, number of batteries, type of batteries, controller power output, motor power rating, etc...). My Jeep Cherokee uses flooded lead acid batteries and a 1000-Amp motor speed controller.

With this setup, acceleration is just as good as it was with the stock 242 6-cyl engine. The only real difference is that it feels stronger at the low end due to the excellent torque characteristics of the series-wound DC motor. Plus, it is a very neat feeling to floor it and get strong acceleration out of the vehicle while making virtually no noise! This level of performance is just fine for me. I didn't build my EV to be a race car or anything like that. But if you do want to see some extremely fast Electric Vehicles, check out the National Electric Drag Racing Association (NEDRA) at: http://www.nedra.com/

The average range of my Jeep on a single charge is about 35 miles. Note that this doesn't mean I'm limited to 35 miles per day, as I can plug in and charge in about 2 hours from a 240-volt outlet, and be ready to go. So it is possible to do much more than 35 miles if you need to do several trips (like when doing errands). Another thing to keep in mind is that lead acid batteries are the worst performers when it comes to energy density (and thus, range). Better batteries do exist, but aren't used in many conversions because the upfront cost is still pretty high. A good example is the Lithium Ion/ Lithium Polymer batteries which are able to provide as much as 300 miles per charge in EV use. These batteries are comming down in price as their applicable markets (such as hybrid vehicles) continue to grow.

beej said:
Agreed, I wouldn't think it would perform too well considering what the XJ weighs...
Yes, but it is all about sizing the electrical system appropiately for a given vehicle. For a heavier vehicle you just use a larger motor, more powerful motor speed controller, larger battery pack, etc... If you didn't, then of course the performance would suffer. It would be just like if you installed a 3-cylinder internal combustion engine into a Jeep Grand Cherokee... you'd get crappy performance because you used the wrong components for the job.

woody said:
I wonder how often do those (twenty) 8vdc rascals will need recycling? and at what cost? Same goes for rebuilding the big DC motor.
Lead Acid batteries like the ones I have typically last 3 to 4 years in EV use. However, their lifespan depends greatly on whether you take proper care of them or not, and people have reported getting as much as 6 years out of them. Even still, lead acid batteries are the cheapest you can buy for EV use, and so replacing them every 3-4 years isn't too bad. Depending on what state you live in, you pay a disposal fee up front when you purchase the batteries, so that is already figured into the price of the battery pack and you don't need to pay anything when you actually go to recycle them.

Rebuilding of the DC motor is not frequent nor complex. Typically the only thing that needs to be replaced routinely on a DC motor is the brushes, which last about 80,000 miles, cost around $50.00 to replace, and can be swapped out in about 10 minutes. That's it... quality electric motors will last a long time (20+ years) before needing any other repair/maintenance work done to them.

casm said:
What gets me about these things is that none of the people who call them 'environmentally friendly' realise that all they're doing is relocating the vehicle's emissions from the tailpipe to the power station.
This is true but only to a point. Studies (including one done by Austin Energy -- Austin, Texas's electric co.) have indicated that it is still much cleaner to drive an EV charged using grid electricity than buring fuel directly in an internal combustion engine. The only pollutant that isn't decreased is Sulfur-Dioxide. Luckily, this pollution and all pollution from power plants is slowly being reduced as more utility companies bring clean wind and solar power online. A last point to make is that if you have to make pollution somewhere, making it at the power plant is better than at everyone's car. Why? Because it is easier to control the emissions of a (relatively) few number of power plants than it is to control the emissions of hundreds of millions of privately-owned tail pipes. As an added bonus, you're moving the pollution source out of the center of cities where people are breathing it in everywhere they go.

bjoehandley said:
If he chose the right motor and wired it right, it'll be incredibly torquey, especially in 4lo!
Yes it is! With my current setup, my Jeep's motor produces about 225-250 ft-lbs. of torque max. The difference is that it can produce this instantly on demand, and from 0 rpm. If I had a more powerful motor controller to drive it, this 9" diameter motor would max out in the area of 450-500 ft-lbs. of torque. There is also 11" or 13" diameter motors I could've chose to use if I had wanted more torque. Though the 13" motor is a bit extreme as it can produce upwards of 1100 ft-lbs. of torque!

Okay, I think I addressed everything. So this is the end of my long-winded, first post. If you've made it this far, I hope it wasn't too boring. If anyone has more questions, just ask... :D

-Nick
http://Go.DriveEV.com/
1988 Jeep Cherokee 4x4 EV
 
Welcome to NAXJA, Nick. Although I applaud your ingenuity in tackling such a project, isn't it also true that the limiting factor in EV development is battery range? This is where the hybrid concept comes into play as an interim measure until fuel cells become viable. Unfortunately, hybrids involve more complexity and cost than is really practical for the average car buyer, and most of these systems only achieve fuel savings in stop and go driving when regenerative braking and idle shutdown come into play. Which is why I am a champion of biodiesel and ethanol... domestic renewable clean burning fuels that fit into our existing infrastructure and keep American dollars in our own economy.
 
MMMMmmmmmm.....1100ft/lbs................

Are brushless motors available for such applications as these yet and affordably priced too?

I'd almost consider the higher torque motor to help overcome battery weight (I've seen what Lithiums can do in RC's and frankly, I'm too chicken to try them in mine yet) The acceleration should be stronger than the original ReNix setup, especially with an electric motors torque band, and be quite a mobil tire smoke generator too (sorry typing what I was daydreaming again.)
 
Hi,

Lawn Cher' said:
Welcome to NAXJA, Nick. Although I applaud your ingenuity in tackling such a project, isn't it also true that the limiting factor in EV development is battery range?
Thanks! Yes, currently the batteries are still the biggest limitng factor in an EV. and thanks to modern electronics, especially Switch Mode Power Supply (SMPS) technology, all the other things that used to be big limiting factors of EVs 15+ years ago (real slow charging, poor acceleration, etc..) have been solved through the ability to make more powerful chargers and controllers, for example.

But fortunately battery technology has and is improving slowly but surely... despite the sad fact that there is little money being put into battery research (at least compare to fuel cells).

Lawn Cher' said:
This is where the hybrid concept comes into play as an interim measure until fuel cells become viable.
I'm not holding my breath for that (fuel cells, that is). Now, It's not that I don't like fuel cells per se, I simply don't like the way that fuel cells and "the hydrogen economy" are being sold to the general public as this "cure-all" that will suddenly solve everything (assuming we keep dumping millions of dollars of research money into it). On the other hand, Battery Electric Vehicles, which have been around for well over 100 years and could be made by the automakers today with a fraction of the money we're throwing into fuel cells, continue to be largely ignored.

It just doesn't make sense to me. We're continuning to drive polluting vehicles saying that it's okay to do so because fuel cells will be here soon to solve everything and then we'll switch technologies. and thus we go on polluting for who knows how long 20? 30? 50? years before fuel cells are ready. Yet, Battery Electric Vehicles work today, and we could start driving them and stop (or at least greatly reduce our level of) polluting *now*.

Lawn Cher' said:
Unfortunately, hybrids involve more complexity and cost than is really practical for the average car buyer
Hybrids are more complex, true... cost, maybe. It depends on how you look at it (upfront cost vs. operating cost, etc.). So does this imply that you think fuel cells vehicles will be simple and affordable? I'm thinking not so much. Affordable... maybe if/when they're mass produced. Simplistic... I wouldn't bet on it. :eek:

Lawn Cher' said:
Which is why I am a champion of biodiesel and ethanol... domestic renewable clean burning fuels that fit into our existing infrastructure and keep American dollars in our own economy.

These are definately a step in the right direction... I too would like to see more vehicles running alternative fuels like these today. However, in the long term, I'm not sure they are the best solution as they still aren't as renewable nor clean as electricity generated from solar/wind power, and they still depend on the inefficient Internal Combustion Engine to do work. But as I say, a step in the right direction for sure! :D

-Nick
http://Go.DriveEV.com/
1988 Jeep Cherokee 4x4 EV
 
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XJNick2 said:
These are definately a step in the right direction... I too would like to see more vehicles running alternative fuels like these today. However, in the long term, I'm not sure they are the best solution as they still aren't as renewable nor clean as electricity generated from solar/wind power, and they still depend on the inefficient Internal Combustion Engine to do work. But as I say, a step in the right direction for sure! :D

-Nick
http://Go.DriveEV.com/
1988 Jeep Cherokee 4x4 EV

Unfortunately only a small percentage of grid power comes from solar/wind sources. Most plants burn coal and/or natural gas, both of which as non-renewable fossil fuels are releasing carbon dioxide into the atmosphere that would otherwise have remained trapped in the earth. Agriculturally derived biofuels merely complete a closed CO2 cycle without adding more to the atmosphere. (Plants breathe CO2, are harvested for their oil, it gets combusted and releases the same CO2.) Not to mention the sulfur that also is released through fossil fuel combustion that is not present in biofuels. So until a majority of power comes from solar, wind and NUCLEAR sources to recharge battery powered vehicles that can match the performance of ICE powered vehicles, we will still be staying with the current paradigm. Biofuels fit right into the existing infrastructure, and are a stepping stone to fuel cells since hydrogen can be chemically stripped from them when that technology eventually matures.
 
Hi,

bjoehandley said:
MMMMmmmmmm.....1100ft/lbs................
Are brushless motors available for such applications as these yet and affordably priced too?

Yes. Brushless AC and DC motors exist for EV use.

All AC drive systems you'll find for EVs use a 3-phase AC induction motor and inverter. The main downsides to AC drive systems is that the AC motors don't have the nice torque curve DC motors have. Also, with an AC induction motor, the commutation is done electronically in the Inverter rather than mechanically in the motor. This means you need more silicon (transistors) in the Inverter for an AC drive then you would need in a comperable DC motor controller to get the same amount of power/torque out of the motor. So AC systems are typically more expensive. Back to DC, there are Brushless DC motors (BLDC) for EV use. These are similar to the AC induction motor setup where you need more silicon in the motor controller, so they are more expensive. However, BLDC motors have other advantages that make them a good compromise between AC induction and the popular series-wound brushed DC motors. The only problem with BLDC motors/controller is that they aren't that easy to get a hold of (at least, not in the sizes needed for a larger EV like a Jeep). :D

-Nick
http://Go.DriveEV.com/
1988 Jeep Cherokee 4x4 EV
 
Hi Nick, and welcome. First off, let me say that I do find your conversion rather interesting, but I still remain skeptical as to the overall benefits of fully-electric vehicles based on currently-available EV technology. Not that I'm ruling them out altogether, but particularly from a hobbyist standpoint it seems as though the available componentry really relegates them to the nifty but not completely practical category.

The average range of my Jeep on a single charge is about 35 miles. Note that this doesn't mean I'm limited to 35 miles per day, as I can plug in and charge in about 2 hours from a 240-volt outlet, and be ready to go. So it is possible to do much more than 35 miles if you need to do several trips (like when doing errands).

Thing is, though, that 35 miles is followed by two hours of downtime. If I could run all my errands in one relatively nearby location in two hours, plug it in while I'm taking care of things, and then go again it wouldn't be such a bad proposition. But I live in Los Angeles - so driving 50 or more miles one-way just to get to the place that has what I need is fairly common. Commuting might be a more realistic proposition, but between start-stop traffic and the 28-mile one-way drive that I have I'd be somewhat concerned about having enough power to make it to work.

Another thing to keep in mind is that lead acid batteries are the worst performers when it comes to energy density (and thus, range). Better batteries do exist, but aren't used in many conversions because the upfront cost is still pretty high. A good example is the Lithium Ion/ Lithium Polymer batteries which are able to provide as much as 300 miles per charge in EV use. These batteries are comming down in price as their applicable markets (such as hybrid vehicles) continue to grow.

Point taken, but they're still largely out of the reach of most hobbyists. The support systems necessary to operate them efficiently are also considerably more complex, from what I understand (and I may be off-base on this, so please correct me if I am).

Lead Acid batteries like the ones I have typically last 3 to 4 years in EV use. However, their lifespan depends greatly on whether you take proper care of them or not, and people have reported getting as much as 6 years out of them. Even still, lead acid batteries are the cheapest you can buy for EV use, and so replacing them every 3-4 years isn't too bad.

Compared to fuel costs across the same time period for the same distance travelled, how do they compare when the up-front cost of the batteries are figured in?

This is true but only to a point. Studies (including one done by Austin Energy -- Austin, Texas's electric co.) have indicated that it is still much cleaner to drive an EV charged using grid electricity than buring fuel directly in an internal combustion engine. The only pollutant that isn't decreased is Sulfur-Dioxide. Luckily, this pollution and all pollution from power plants is slowly being reduced as more utility companies bring clean wind and solar power online. A last point to make is that if you have to make pollution somewhere, making it at the power plant is better than at everyone's car. Why? Because it is easier to control the emissions of a (relatively) few number of power plants than it is to control the emissions of hundreds of millions of privately-owned tail pipes. As an added bonus, you're moving the pollution source out of the center of cities where people are breathing it in everywhere they go.

I'm going to have to disagree with some of the points in this paragraph.

- While they may claim it's cleaner to relocate emissions to the power station, what happens when there are literally tens of thousands (or, as could hypothetically be the case in this part of the country, millions) of EVs plugged in and charging at any given time? We've already got power shortages and rolling blackouts here, plus virtually none of our power supplied by non-fossil stations. Either a) we get modern nuclear power stations to handle the extra load (which will never happen in California because the granolamunchers are scared of it), or b) we burn more fossil fuel in the plants that would've just gone into the tank anyway. At best, it's a zero-gain proposition.

- WRT the above, controlling plant emissions is a function of plant fuel type and production scale. Could we realistically scrub that much plant pollution with widescale EV adoption? Also, I don't see how it's any harder to control emissions on private vehicles - they're tested periodically, the same as the plants are; the only difference is that it's being done on a micro rather than macro scale. Further, what happens when a plant can't pass smog and has to be shut down while repairs are carried out? It'd be considerably more than just the EV drivers who are inconvenienced by this.

- By moving the pollution source out of the cities, all you're doing is pushing it out into the country. People do live there too. Nobody wants to be downwind from the problem in either case, but all this is doing is getting it out of the urban backyard and into the rural one.

Not trying to knock what you've accomplished, but like I say I'm still skeptical as to the overall benefits of EVs. Out of curiosity, have you looked into regenerative braking systems or storage battery flywheels?
 
Schwarzenneger is pushing for a new law in California that would provide strong incentives for more individual solar electricity installations. The objective is to get a million homes in Calif. with some sort of solar panels on the roofs within 5 years. The law has strong support from a wide range of business and green-type organizations.

Here's the kicker. The Democrats in the California legislature--who you would normally assume would support something like this--may kill it for no other reason than that it would be perceived as a "win" for Arnold. In other words, it's looking now like the Dems may allow partisanship to trump all. Is that friggin' STUPID, or what!?!

(In the interest of honesty, I should point out, it's not like the Republicans have never before let partisanship trump all. I firmly believe that partisanship is the largest sub-category of stupidity that exists.)
 
dmillion said:
Schwarzenneger is pushing for a new law in California that would provide strong incentives for more individual solar electricity installations. The objective is to get a million homes in Calif. with some sort of solar panels on the roofs within 5 years. The law has strong support from a wide range of business and green-type organizations.

Can you tell me if it covers only solar or other off-grid power types as well? This is something I'm actually quite interested in and would really appreciate a link to the bill / proposal.

Here's the kicker. The Democrats in the California legislature--who you would normally assume would support something like this--may kill it for no other reason than that it would be perceived as a "win" for Arnold. In other words, it's looking now like the Dems may allow partisanship to trump all. Is that friggin' STUPID, or what!?!

It's friggin' stupid, and also the nature of CA politics.

(In the interest of honesty, I should point out, it's not like the Republicans have never before let partisanship trump all. I firmly believe that partisanship is the largest sub-category of stupidity that exists.)

They both suck, just in different ways. Seriously, though, this cutting off the nose to spite the face isn't doing anyone any good. Let's fire the whole damn lot of them and replace politicians with volunteer elected appointees with a blanket 1-term limit.
 
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