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Discussion Starter #1
Actually joined a while back but this EV thing got me thinking again.. my new idea is since these can be plugged in to 110v, 20a power to charge, what about also mounting a Honda eu2000 to always be charging the batteries like the hybrid cars?sounds too simple to work. What am I missing?
 

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That's called a series gas-electric hybrid, because all of the power output of the engine becomes electricity, before going to the motor to become shaft power.

This is a very commonly proposed idea, because it sort of makes sense.

The problems:
  • the small engine is not efficient enough
  • a reasonable size of engine to carry is not sufficient to keep up with average power demand, so range is still battery-limited (although extended)
  • the inefficiency of the generator and the electric motor combine to make the hybrid system a relatively inefficient transmission
  • as with any hybrid, you have all the complexity of both a gas-engine powertrain and a battery-electric powertrain
A minor complication is that EVs are generally designed to prevent external charging and running at the same time, so if you try to do this with a production EV some modification is required... you can't just put the generator set on a hitch or trailer and plug the car in to charge while driving.

Remarkably few DIY EV people seem to care about pollution, but I'll also point out that a portable generator set does not run nearly cleanly enough to meet modern automotive emissions standards.
 

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Discussion Starter #3
I understand the environmental thing and the pollution of the generator. My idea wasn't really to use it to get unlimited miles, but to extend the range maybe just a little to make this cheap project feasible. I'm seeing these guys on these videos getting like a 25 mile range with Fla or agm batteries, which is what I'll be using because lithium cost more than I want to spend on the project. But those does have me thinking even deeper. I don't know my way around here yet, which topic heading would i post a proposed project on?
 

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Discussion Starter #4
Now that you have me thinking of this, here is what is going through my head.
I have a 62 CJ5 that only has the frame, body, axles and 3 speed transmission with a transfer case that has an overdrive unit. I am thinking ofbuilding a JEEP that gets rediculous mpg, especially since it has the aerodynamics of a brick. Oh, it has factory 5.38 gears and the Warn O/D is .25.
So get a small efficient gas engine and attach it to the bell housing and an electric motor attached to the front output of the t-case to push/help the gasses not have to run so hard. With this set up, I can disengage the electric motor at speeds it's not helping, (in reality, it won't be at highway speeds much so that really could be just a bragging point) or when the batteries die to reduce whatever drag it might have. I'm hoping with this type of setup I can take the original 10 mpg to40-50 or more! Optimistic? Doable?
 

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Also with this kind of set up, my intention would really be to give it outrageous fuel economy, would really only drive it when the batteries could help.
Since my head just floods with ideas when I get on a roll, I could set the electric motor with regeneration capabilities and with this transfer case I have (D-18), I could disengage the rear output and generate power in a pinch driving only the front output
 

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Also with this kind of set up, my intention would really be to give it outrageous fuel economy, would really only drive it when the batteries could help.
The only thing outrageous about fuel economy in a low-tech series hybrid is how bad it is. The BMW i3 with "range extender" is this type of hybrid, and despite advanced technology and a carbon-fibre body it still gets worse fuel economy than a typical cheap compact car with a gas engine.

Since my head just floods with ideas when I get on a roll, I could set the electric motor with regeneration capabilities and with this transfer case I have (D-18), I could disengage the rear output and generate power in a pinch driving only the front output
I'm not sure what component you are thinking of putting where, but
  1. never run a generator from one set of wheels while driving the other set with an engine (that's called a through-the-road hybrid, and it's really inefficient), and
  2. if you can get power from an engine to wheels mechanically, do that rather than going through a generator and a motor.
 

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I have a 62 CJ5 that only has the frame, body, axles and 3 speed transmission with a transfer case that has an overdrive unit. I am thinking of building a JEEP that gets rediculous mpg, especially since it has the aerodynamics of a brick.
...
So get a small efficient gas engine and attach it to the bell housing and an electric motor attached to the front output of the t-case to push/help the gasses not have to run so hard. With this set up, I can disengage the electric motor at speeds it's not helping, (in reality, it won't be at highway speeds much so that really could be just a bragging point) or when the batteries die to reduce whatever drag it might have.
Okay, that's a parallel hybrid... and apparently now a 2WD since the electric motor is taking the place of the shaft to the front axle. A well-designed hybrid system does help fuel economy... moderately, and not in steady-speed conditions.

I'm hoping with this type of setup I can take the original 10 mpg to40-50 or more! Optimistic? Doable?
Massively optimistic, and not doable, unfortunately.
 

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Discussion Starter #9
Brian, I'm just spitballing here now, but I am starting to think of the parallel hybrid. My t-case has 4 input/outputs I'll be working with. One has the overdrive unit, the main input where the gas motor would me attached. The 2 outputs can be run front or rear, both front and rear or neither. The front output would not be connected to an axle. Rather to the electric motor. At those steady speeds you said it doesn't help, it coud be turned off to save the batteries. But its for to and from work or school, depending on who is driving. After it is determined what the actual range is, would determine if the gas is used at all.
It could work to assist only is acceleration like those hub motors I've read about. The Glaser wouldn't be used much, so any of the miles used only electric would greatly increase the mpg.
 

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... I am starting to think of the parallel hybrid. My t-case has 4 input/outputs I'll be working with. One has the overdrive unit, the main input where the gas motor would me attached. The 2 outputs can be run front or rear, both front and rear or neither. The front output would not be connected to an axle. Rather to the electric motor.
The more obvious configuration for the basic Dana 18 transfer case would be to put the motor on the PTO/overdrive port, but of course you can't both have the motor there and have the overdrive. The result is that you give up 4WD to have the motor connected this way.

Can you really connect just the front output? That would be abnormal for a transfer case: normally the rear is always connected and you can just connect or disconnect the front (as well as selecting between direct and reduction gearing, called "Hi" and "Lo" range). It also doesn't matter, as you don't need to connect the front/motor shaft without connecting the rear output.

At those steady speeds you said it doesn't help, it coud be turned off to save the batteries. But its for to and from work or school, depending on who is driving. After it is determined what the actual range is, would determine if the gas is used at all.
It could work to assist only is acceleration like those hub motors I've read about. The [gas engine] wouldn't be used much, so any of the miles used only electric would greatly increase the mpg.
It doesn't really hurt to leave the motor mechanically connected and spinning when not powered, although with a brushed motor there is some drag.

Generally in a parallel hybrid the electric motor isn't used much except when accelerating (as a motor) and when braking (as a generator), and for some periods as a generator to restore energy used during acceleration.

"Those hub motors" don't exist in any production vehicle, because they're not useful.

As a plug-in hybrid, any energy that you put in the battery while parked and use up while driving replaces burning gasoline. I wouldn't call this increasing miles per gallon, because it isn't using the gasoline any more efficiently.
 

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Discussion Starter #11
Brian, the D-18 has 2 lever, and in my case 3. One for the O/D, PTO port, and one for each axle. Each of those have 3 positions, H-N-L. If I put the motor on the PTO, losing the OD would keep me off of the freeway for safety. It has 5.38 gears, and top speed when produced was about 50 MPH.
I also realise the trade off where I still need electrity. My intent for right now is to not buy gas directly, and as I build my system, get the electric from solar. There is of course the bragging rights of saying I'm driving an old CJ5 and getting 75 miles for a gallon of gas! Lol
Also trying to build cheap. As much as possible will come from the "junk" yard. Already have the stripped down JEEP that's been suiting in yard for 20 years, and it's old enough to be smog exempt. DMV never needs to see it.
 

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Brian, the D-18 has 2 lever, and in my case 3. One for the O/D, PTO port, and one for each axle. Each of those have 3 positions, H-N-L.
Maybe it's just the description which isn't clear, but what this describes - with a High/Neutral/Low for each axle - is unlike any transfer case I've heard of, and wouldn't make any sense. It would allow one output to be in high while another was in low, which would be useless, would destroy parts, and would require excessive mechanical complexity.

Classic transfer cases like the Dana Spicer 18 are reasonably straightforward.
  1. The front axle drive lever connects and disconnects the front output flange to the output shaft; the rear output always stays connected to the output shaft. This is the 2WD/4WD shifter.
  2. One lever shifts between the gear set for direct drive (1:1 ratio, called high range) and the gear set for reduction (usually 2.46:1, called low range). This range shift lever is usually labelled H/N/L. In the D-18, this engages the helical high range driven gear or the spur low range driven gear to the output shaft.
  3. With a PTO or the D-18's overdrive, there's another lever to engage that extra set of gearing; when not engaged, the input shaft directly (1:1) runs the drive gear on the main shaft, and when engaged the input shaft speed is stepped up to run that drive gear faster (25% faster in the common Warn unit).
So it isn't one lever for each axle; it's one lever for each function. Only one lever is H/N/L, and it is for both axles. This is a typical driver's information plate for the Model 18, showing the function of the two transfer case levers and the transmission shift lever; with a PTO or overdrive there's one more lever, not shown in this case:


The front axle drive (2WD/4WD) and gear range (H/N/L) shifters are normally interlocked, so you can't select 2WD while in low range, leaving only the typical 2H, 4H, N, and 4L combinations. This interlock can be removed in the D-18, so you can have 2L as well. In the proposed configuration, instead of 2WD and 4WD, you would be shifting between gas-only and gas+electric (and always only RWD). Removing the interlock would let you use low range with the electric motor disconnected.

While there's little point using both overdrive and low range at the same time, it's presumably possible.

If I put the motor on the PTO, losing the OD would keep me off of the freeway for safety. It has 5.38 gears, and top speed when produced was about 50 MPH.
Yes, that's why I understand wanting to keep the overdrive. There are apparently overdrives which also have PTO, so you could have both, but only if you had that style of overdrive, only the PTO is live while the overdrive is in both ratios, and only if the PTO is strong enough for this purpose (it usually just drives something like a winch).
 

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Discussion Starter #13
Brian, that may be for the D18. I never had it running and the last time I even looked at it was over 10 yrs ago. I have an Atlas ll in my 99 and it shifts the way I described the D18.They way you described would still work. To move it, the rear always would need to be connected. To run the electric, engage 4wd and either put the transmission or the t-case in N. I'm hoping with the low gears, electric can be run in direct drive
I think it would still work if the miles driven are close to what the charge can deliver.
 

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I have an Atlas ll in my 99 and it shifts the way I described the D18.
I found an image of the Atlas 2 opened up, and I can see how they did that... but it's an inline transfer case, while the Dana 18 is an offset design, and that changes what system is mechanically simplest.

For the mechanically curious, it appears [and is confirmed by the service manual] that the Atlas has
  1. a sliding shifter on the rear output shaft (which is inline with the input) to either
    • connect the rear output directly to the input (H), or
    • connect the rear output to the gear at the rear to create a power path from input shaft to intermediate to rear output, with both gear transfers being reductions (L), and
  2. a similar sliding shifter on the front output shaft, which can either
    • connect the front output to the input via the gears at the front, so the power path is a 1:1 transfer (through the intermediate gear cluster as an idler), for High, or
    • connect the front output to the gear at the rear to create a power path from input shaft to intermediate to rear output, with both gear transfers being reductions (L)
I think this might actually be a common design for gear-drive inline transfer cases, but they normally wouldn't have separate shift levers, at least in recent decades.

Still...
It would allow one output to be in high while another was in low, which would be useless, would destroy parts...
Never put one of those levers in High while the other is in Low in a vehicle with the both outputs going to axles. :eek:
[Edit note: according to Atlas documentation, internal interlocks prevent these combinations, as well as high range front-drive-only]​

Being able to connect only one output - and either one - is occasionally a bit useful, although not for the current project.

On the other hand, if you used this design of transfer case for your hybrid project, you could run the front connection to the electric motor in "low" (so it would turn faster) while the rear connection was in "high".

They way you described would still work. To move it, the rear always would need to be connected. To run the electric, engage 4wd and either put the transmission or the t-case in N.
I agree. :)
 

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Discussion Starter #16
Since I'm only dreaming, crunching ideas, having the front (electric motor) turn faster than the gas motor with gear reducer between the case and electric motor. This would start making everything heavy and expensive, but if that type of setup would get mpg rate to an acceptable range, some custom components could be created. Make a custom t-case which really only combines the motors with either one is operating or both, however the most efficient result is had.
What if I redefine the goal to build a vehicle that has a range of 50 miles per day while using a half of a gallon of gas per day. A take specific car to take a person to work or school, using recycled and modified recycled parts.
I'm sure with all my daydreaming I will come up with a viable concept!
I don't mind being told I'm wrong or it can't be done that way, but I want to know why. Only way to learn. I've enjoyed this back and forth discussion
 

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Discussion Starter #17
Or, what about skipping the T-case all together, drive each axle separately. Save a lot of weight and could gear each axle to maximize both the gas and electric.
 
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