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Howdy there!

So, as is the case with most people who only skim the edge of EV or hybrid lifestyle for the sake of saving money with abundant pondering, "research" and the inevitable dismissal of stepping into a new off the lot vehicle (because buying a new vehicle to save money kinda works against itself......), I find myself now thinking of converting an existing vehicle to a hybrid. The idea to look into this topic came to me after realizing afew automakers use a front ICE and rear electric motor set up to achieve their hybrid performance. I thought "surly guys are doing the same thing to their cars". After acouple searches and finding out how some folks are doubling up the EV part of their Prius's to get amazing mileage, I come find very sparse info on afew companies offering DIY kits to fit to your standard everyday car for about $3000! "Oh Boy!", I exclaimed to myself! "This is exactly what I'd want!" trouble is, most articles are about 10 years old and nearly every company mentioned doesn't exist, the site page is down or that company mentioned for making kits seemingly now only sells parts for full EV conversions. And to top it off, I have to wonder why this sort of accessible ability to vamp up your fuel savings isn't the hottest "weekend project" by now?

Maybe the above is alittle messy, sorry about that. The main questions I'd like to discuss are why these kits aren't around "anymore"? And if I'm missing something here, who legitimately offers DIY Hybrid kits for the slightly above average DIY car owner?

Thanks kindly!

Ti
 

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Hi
If you want to save money you are barking up the wrong tree!

Cheapest is to run an old IC car
Next cheapest is a second hand EV

Converting will cost you twice as much as the second hand EV and be half as good

That is all for EV's

Hybrids are worse! - much more difficult - much more expensive - much less benefit

Sorry!

Saving money is not where it's at - converting to an EV is more of a "Hot Rod" option
 

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. The idea to look into this topic came to me after realizing afew automakers use a front ICE and rear electric motor set up to achieve their hybrid performance.
One problem is that there is far more to creating a functional hybrid than adding an electric drive unit to the rear of a car with an engine and transaxle in the front. Toyota's hybrids use a completely different transaxle than their non-hybrids; the rear unit is just an add-on for AWD if desired, to a vehicle which is hybrid even in 2WD form. Even in other hybrid systems, which use a conventional transmission, making a hybrid means adding a motor-generator to that engine and transmission, usually placed between them; this is not a reasonable thing to do aftermarket or DIY.

There is at least one add-on parallel hybrid system - using a belt-drive motor stuck on the engine - but it's not very functional compared to a properly integrated design.

A hybrid conversion could be an interesting project, but I agree that it would not be economically viable.
 

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One problem is that there is far more to creating a functional hybrid than adding an electric drive unit to the rear of a car with an engine and transaxle in the front. Toyota's hybrids use a completely different transaxle than their non-hybrids; the rear unit is just an add-on for AWD if desired, to a vehicle which is hybrid even in 2WD form. Even in other hybrid systems, which use a conventional transmission, making a hybrid means adding a motor-generator to that engine and transmission, usually placed between them; this is not a reasonable thing to do aftermarket or DIY.

There is at least one add-on parallel hybrid system - using a belt-drive motor stuck on the engine - but it's not very functional compared to a properly integrated design.

A hybrid conversion could be an interesting project, but I agree that it would not be economically viable.
I see you posted this in 2019, do you and Duncan still feel the same? I think I could easily slip an electric motor between the tranny and rear end of a small pickup, put a half dozen car batteries in back and connect some standard control to the system, maybe even get some regen and solar. My son and grandson are willing to help, gearheads all. I'm a weldor and mechanic, both of them totally capable. To me, the biggest challenge is the interface at the gas pedal.
 

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Hi
If you want to save money you are barking up the wrong tree!

Cheapest is to run an old IC car
Next cheapest is a second hand EV

Converting will cost you twice as much as the second hand EV and be half as good

That is all for EV's

Hybrids are worse! - much more difficult - much more expensive - much less benefit

Sorry!

Saving money is not where it's at - converting to an EV is more of a "Hot Rod" option
Boy, you're a real pessimist, but I plan to carry on anyway. I started a thread in the 'Introduce Yourself' Colum.
Can I just abandon it and take off here, or do I need to start another thread? I'm replying to Brian's reply.
 

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I see you posted this in 2019, do you and Duncan still feel the same?
I don't think anything has changed, but it's still an interesting project if you want to try it.

I think I could easily slip an electric motor between the tranny and rear end of a small pickup, put a half dozen car batteries in back and connect some standard control to the system, maybe even get some regen and solar. My son and grandson are willing to help, gearheads all. I'm a weldor and mechanic, both of them totally capable. To me, the biggest challenge is the interface at the gas pedal.
Certainly the pickup with this motor placement is the easiest hybrid configuration to build.

One feature that makes this sort of easy-to-add hybrid system not optimal, and thus hard to justify, is that the motor is fundamentally not in the optimal place. It has recently become popular to describe parallel hybrids by the position of the motor-generator:
  • P0/P1 - At the engine
    • can replace the conventional alternator and starter motor, but can't drive the vehicle unless the engine is running
    • P0 or P1f: at the front of the engine, usually an accessory belt drive like an alternator
      • easy to add, but limited in power
      • examples: Ram eTorque, GM eAssist
    • P1 or P1r: at the rear of the engine, usually a gear drive like a starter
      • difficult to add
      • examples: early Honda systems, such as the Insight, with the Integrated Motor Assist (IMA)
  • P2 - At the transmission input
    • separated from the engine by a clutch, so it can drive the vehicle without the engine is running
    • difficult to add to an existing vehicle; required transmission modification
    • example: current Ford systems in longitudinal-engine SUVs and F-150
  • P3 - Between the transmission output and the final drive
    • relatively easy to add to traditional front engine / rear drive vehicles, but not practical with a transaxle
    • does not take advantage of transmission gearing so motor must run over wide speed range and needs additional gearbox or large motor for sufficient torque
    • example: Azure Dynamics Balance system (circa 2010)
  • P4 - after the final drive
    • can be completely separate from the engine-based powertrain
    • does not take advantage of transmission gearing so motor must run over wide speed range and needs additional gearbox or large motor for sufficient torque
Add-on hybrid systems typically fall into the P0 (or P1f) or P3 categories, because they are easy to do, but these are the least capable hybrid configurations, which is why OEMs only use P0/P1 for "mild" (low cost / low capability) systems, and don't use P3 at all.

After listing this, I searched for an online article to confirm the Px designation system and found this one for another writer's assessment of the same issues:
Mild Hybrid Electric Vehicle (MHEV) – architectures

... and connect some standard control to the system, maybe even get some regen and solar. My son and grandson are willing to help, gearheads all. I'm a weldor and mechanic, both of them totally capable. To me, the biggest challenge is the interface at the gas pedal.
With this P3 motor position (and a 2WD truck), mechanically building it is the straightforward part (although still beyond most home mechanics). Connecting to the accelerator pedal is easy, but the problem is what to do with that signal. Does the hybrid control system determine when the engine is not needed and shut it down, then restart it quickly enough when needed? Does the control system reduce engine throttle setting to compensate for power delivered by the electric motor? When does regenerative braking occur, how much is used, does it occur only when the brake pedal is used, does it respond to the force on the brake pedal? Regenerative braking only affects the rear wheels, so when it is used

It is certainly possible to do a simple add-on parallel hybrid, but if it doesn't handle these issues well it won't be as beneficial as a properly integrated system, and it is a complex problem to handle them well. Even factory hybrids are often criticized for their integration of the engine and electric system not working smoothly enough.
 

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Really great post, Brian, thanks so much for your time. Things still look possible for me. I'll be keeping it simple, control the gas motor with a switch, no microprocessor there. I remember electric trailer brakes when hauling boats, they connected simply and supplemented the truck brakes, a nice system. That little bit of travel before the master cylinder is engaged can be just right for regen control. Definitely going P3, I'm not worried. Worked many years as a fabricator in a machine shop after years of being a machinist. I have a good welding/machine shop downtown who has been very helpful with my current project, a step-climbing hand truck. Sure wish I could market those things! But that's another story.
 

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Hi there!

Saw this thread was interested because I have been toying with the idea of making a diy electric drive to my ford probe's rear wheels.

But to your truck:
My friend has a toyota dyna and it has an interesting handbrake. It's a single disc located around the cardinac axle. Could this be a place for a electric motor for a pickup? then you dont beed to drive electric power thru gearbox, nor rotate engine with it (and thus have power loss)
And you could also engage E-motor during normal drive, lowering engines workload.

I was thinking one would need a magnetic switch (like in ac motor) to turn belt/gear drive of motor on/off, so it wouldn't cause resistance to engine.
I also was thinking about kinetic energy reclaiming (sorry I'm not native english speaking person so I use the words I know)
What if you had 1 or 2 car accu chargers behind a magnetic switch too. whenever you wanted to drop speed or roll down hill you could engage the chargers and let them slowly draw your speed to charge batteries. This system could also be attached to cardinal axle.

Best regards.
Lionking
 

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Hi there!

Saw this thread was interested because I have been toying with the idea of making a diy electric drive to my ford probe's rear wheels.

But to your truck:
My friend has a toyota dyna and it has an interesting handbrake. It's a single disc located around the cardinac axle. Could this be a place for a electric motor for a pickup? then you dont beed to drive electric power thru gearbox, nor rotate engine with it (and thus have power loss)
And you could also engage E-motor during normal drive, lowering engines workload.

I was thinking one would need a magnetic switch (like in ac motor) to turn belt/gear drive of motor on/off, so it wouldn't cause resistance to engine.
I also was thinking about kinetic energy reclaiming (sorry I'm not native english speaking person so I use the words I know)
What if you had 1 or 2 car accu chargers behind a magnetic switch too. whenever you wanted to drop speed or roll down hill you could engage the chargers and let them slowly draw your speed to charge batteries. This system could also be attached to cardinal axle.

Best regards.
Lionking
Your replies are correct. It is easy to install a motor between the transmission and the rear end, motors with splined ends are available. You just have to adapt driveshafts. That takes experience, and a proper machine shop is helpful. It's what I used to do. Working out the controls is the challenge, but a fun one. Of course, the motor has to be strongly attached to the vehicle, more talent in fabrication and welding needed there.
 

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My friend has a toyota dyna and it has an interesting handbrake. It's a single disc located around the cardinac axle. Could this be a place for a electric motor for a pickup? then you dont beed to drive electric power thru gearbox, nor rotate engine with it (and thus have power loss)
And you could also engage E-motor during normal drive, lowering engines workload.
While I'm not sure what the term "cardinac axle" was supposed to be (perhaps "cardinal axle", intended to mean "main shaft"?) I assume that you mean the propeller shaft, which is the drive shaft from the transmission to the drive axle. Many trucks have a parking brake at the transmission output on this shaft, if they don't have parking brakes at the wheels.

This is a workable location for the motor of a parallel hybrid, and it is what I described as the "P3" position in my post (#6). It is what mike is already planning.

I also was thinking about kinetic energy reclaiming (sorry I'm not native english speaking person so I use the words I know)
What if you had 1 or 2 car accu chargers behind a magnetic switch too. whenever you wanted to drop speed or roll down hill you could engage the chargers and let them slowly draw your speed to charge batteries. This system could also be attached to cardinal axle.
This is called regenerative braking. It is a normal feature of all hybrids and modern electric vehicles, and is easy to do with any AC motor.

I don't know what you mean by "accu chargers" (perhaps battery chargers?) but regenerative braking is done with the same motor and same controller/inverter as used to drive the vehicle.
 

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While I'm not sure what the term "cardinac axle" was supposed to be (perhaps "cardinal axle", intended to mean "main shaft"?) I assume that you mean the propeller shaft, which is the drive shaft from the transmission to the drive axle. Many trucks have a parking brake at the transmission output on this shaft, if they don't have parking brakes at the wheels.

This is a workable location for the motor of a parallel hybrid, and it is what I described as the "P3" position in my post (#6). It is what mike is already planning.


This is called regenerative braking. It is a normal feature of all hybrids and modern electric vehicles, and is easy to do with any AC motor.

I don't know what you mean by "accu chargers" (perhaps battery chargers?) but regenerative braking is done with the same motor and same controller/inverter as used to drive the vehicle.
Thanks for the reply, Brian, you're a great help. I'm new to EV, so help me out. EVs use AC motors, so inverters are used to convert DC from the batteries to AC? How is regenerative braking done with the AC motor? What phase is used for EVs?
 

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I'm new to EV, so help me out. EVs use AC motors, so inverters are used to convert DC from the batteries to AC? How is regenerative braking done with the AC motor? What phase is used for EVs?
Yes, they're all AC. Yes, that means an inverter converts the DC supply to AC... and controls the voltage and current. Regenerative braking is a matter of changing the timing of the pulsing of the inverter transistors (currently insulated gate bipolar transistors or IGBTs are normally used), which is handled by the controller logic. They're normally 3-phase, but some large motors used in heavy trucks and buses run more phases.

All of this is true whether the motor is asynchronous (induction), or synchronous (permanent magnet, now typically with a reluctance component as well). Decades ago they were almost all induction, but now they're generally permanent magnet other than some which the manufacturer wants to be able to spin freely when not powered (e.g. one axle of an AWD vehicle). This suggests that induction might still be a good choice for a hybrid in which the motor is often doing nothing, and indeed the Azure Dynamics Balance hybrid that I mentioned earlier - which uses the P3 configuration with the motor inline with the propeller shaft in a medium-duty truck chassis - used a big induction motor.
 

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Yes, they're all AC. Yes, that means an inverter converts the DC supply to AC... and controls the voltage and current. Regenerative braking is a matter of changing the timing of the pulsing of the inverter transistors (currently insulated gate bipolar transistors or IGBTs are normally used), which is handled by the controller logic. They're normally 3-phase, but some large motors used in heavy trucks and buses run more phases.

All of this is true whether the motor is asynchronous (induction), or synchronous (permanent magnet, now typically with a reluctance component as well). Decades ago they were almost all induction, but now they're generally permanent magnet other than some which the manufacturer wants to be able to spin freely when not powered (e.g. one axle of an AWD vehicle). This suggests that induction might still be a good choice for a hybrid in which the motor is often doing nothing, and indeed the Azure Dynamics Balance hybrid that I mentioned earlier - which uses the P3 configuration with the motor inline with the propeller shaft in a medium-duty truck chassis - used a big induction motor.
Thanks so very much, Brian. I will save this thread. You're really good at explaining this stuff, Tesla would be proud of you. I didn't know any AC motors had any magnets in them.
 

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I don't think anything has changed, but it's still an interesting project if you want to try it.


Certainly the pickup with this motor placement is the easiest hybrid configuration to build.

One feature that makes this sort of easy-to-add hybrid system not optimal, and thus hard to justify, is that the motor is fundamentally not in the optimal place. It has recently become popular to describe parallel hybrids by the position of the motor-generator:
  • P0/P1 - At the engine
    • can replace the conventional alternator and starter motor, but can't drive the vehicle unless the engine is running
    • P0 or P1f: at the front of the engine, usually an accessory belt drive like an alternator
      • easy to add, but limited in power
      • examples: Ram eTorque, GM eAssist
    • P1 or P1r: at the rear of the engine, usually a gear drive like a starter
      • difficult to add
      • examples: early Honda systems, such as the Insight, with the Integrated Motor Assist (IMA)
  • P2 - At the transmission input
    • separated from the engine by a clutch, so it can drive the vehicle without the engine is running
    • difficult to add to an existing vehicle; required transmission modification
    • example: current Ford systems in longitudinal-engine SUVs and F-150
  • P3 - Between the transmission output and the final drive
    • relatively easy to add to traditional front engine / rear drive vehicles, but not practical with a transaxle
    • does not take advantage of transmission gearing so motor must run over wide speed range and needs additional gearbox or large motor for sufficient torque
    • example: Azure Dynamics Balance system (circa 2010)
  • P4 - after the final drive
    • can be completely separate from the engine-based powertrain
    • does not take advantage of transmission gearing so motor must run over wide speed range and needs additional gearbox or large motor for sufficient torque
Add-on hybrid systems typically fall into the P0 (or P1f) or P3 categories, because they are easy to do, but these are the least capable hybrid configurations, which is why OEMs only use P0/P1 for "mild" (low cost / low capability) systems, and don't use P3 at all.

After listing this, I searched for an online article to confirm the Px designation system and found this one for another writer's assessment of the same issues:
Mild Hybrid Electric Vehicle (MHEV) – architectures


With this P3 motor position (and a 2WD truck), mechanically building it is the straightforward part (although still beyond most home mechanics). Connecting to the accelerator pedal is easy, but the problem is what to do with that signal. Does the hybrid control system determine when the engine is not needed and shut it down, then restart it quickly enough when needed? Does the control system reduce engine throttle setting to compensate for power delivered by the electric motor? When does regenerative braking occur, how much is used, does it occur only when the brake pedal is used, does it respond to the force on the brake pedal? Regenerative braking only affects the rear wheels, so when it is used

It is certainly possible to do a simple add-on parallel hybrid, but if it doesn't handle these issues well it won't be as beneficial as a properly integrated system, and it is a complex problem to handle them well. Even factory hybrids are often criticized for their integration of the engine and electric system not working smoothly enough.
P1 = Gear Drive like first gen Honda Insight...needs editing for accuracy!
 

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P1 = Gear Drive like first gen Honda Insight...needs editing for accuracy!
I didn't say that "P1 = Gear Drive". P1 defines a location in the power flow (at the engine output), and gear drive is only typical ("usually", not "always"). The original version of Honda's IMA is integrated with the flywheel, and thus P1; it does not use a gear drive.

Insight.Commuter, if you have a correction be constructive and provide it, don't just say something is wrong (especially with an incorrect paraphrasing of what you think is wrong). Not a great start to your participation in this forum.
 

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Hi People, I've been thinking along similar lines, except I've been looking at how electric motors can be built into the wheel assembly. These are known as hub motors. See for example: https://www.printedmotorworks.com/in-wheel-motors/
Ideally it requires little change to the car, but gives an electric assistance, improved economy and lower emissions. May also add performance if used as additional source if power. Like you hooking up to the controls to produce safe operation is a big challenge.
 

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But to your truck:
My friend has a toyota dyna and it has an interesting handbrake. It's a single disc located around the cardinac axle. Could this be a place for a electric motor for a pickup? then you dont beed to drive electric power thru gearbox, nor rotate engine with it (and thus have power loss)
And you could also engage E-motor during normal drive, lowering engines workload.
Yeah that is a common location, my old 40 series Landcruiser had that too. Great location for an electric motor, although matching the RPMs to something usable will be hard.

I was thinking one would need a magnetic switch (like in ac motor) to turn belt/gear drive of motor on/off, so it wouldn't cause resistance to engine.
I also was thinking about kinetic energy reclaiming (sorry I'm not native english speaking person so I use the words I know)
What if you had 1 or 2 car accu chargers behind a magnetic switch too. whenever you wanted to drop speed or roll down hill you could engage the chargers and let them slowly draw your speed to charge batteries. This system could also be attached to cardinal axle.
A brushless (BLDC/AC) motor doesn't give much resistance when it is not working (no power or regen) so you don't need an extra magnetic switch. Just don't use the motor and it is fine.
I would just check throttle position, no throttle == apply regen if system enabled. This may also work as "hill hold".
 
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