# DIY Mild Hybrid



## brian_ (Feb 7, 2017)

What you're describing is a *parallel* hybrid - the engine and electric motor are in parallel (either one can drive without the other). Many production hybrids have been parallel designs.

A "*mild* hybrid" has an electric system of very low capacity - it can't drive at all without the engine, has very little energy storage, and usually runs on only 42 or 48 volts (nominal).


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## brian_ (Feb 7, 2017)

Do-It-Yourself projects are great learning experiences, but if all you really want is a hybrid SUV, and a Yukon or Tahoe is suitable, perhaps you can just buy a used one... the 2008-2013 Tahoe/Yukon hybrid used the most advanced hybrid transmission produced so far.


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## brian_ (Feb 7, 2017)

matt4x4 said:


> ... I see some setups have an electric motor attached to the output of the transmission on one side, the other side would connect to the drive shaft in some way. So a shorter drive shaft would be in order, securing the electric motor and figuring out a way to connect the shaft of the electric motor to the output of the transmission or transfercase, and the drive shaft.


This was the approach used in the Balance Hybrid Electric system by Azure Dynamics (for commercial vehicles and small buses) based on the Ford E-450 chassis:








(this illustration shows the traction motor, the Ford engine and transmission ahead of it and the axle behind it are not shown)

Any motor mounted inline with the driveshaft this way, without any gearing, is forced to run at relatively low speed. The suitability of this depends on the motor.


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## brian_ (Feb 7, 2017)

matt4x4 said:


> Leaving the i.c.e. intact to be able to drive on gas when I wish, and adding an additional electric motor somewhere in the drivetrain to help with MPG.


Just to be clear, what are you expecting...

To help with miles per gallon of gas by using electrical energy stored in a battery (charged at home or other charging station) instead of using gas?
To help the efficiency of the gas engine by leveling out load, by avoiding idling, and by recovering energy by regenerative braking?
How you expect this to work determines the capabilities required of the hybrid system, including energy storage capacity, regenerative braking ability, and control of the gas engine.


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## rmay635703 (Oct 23, 2008)

My 82 2wd c-code Diesel Suburban with a 5 speed shift and 2.8 rear gears would get almost 30mpg at 55mph

Perhaps something easier would get you your goal?


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## PAXtss (Dec 16, 2017)

brian_ said:


> Do-It-Yourself projects are great learning experiences, but if all you really want is a hybrid SUV, and a Yukon or Tahoe is suitable, perhaps you can just buy a used one... the 2008-2013 Tahoe/Yukon hybrid used the most advanced hybrid transmission produced so far.


Matt
Brian, once again nails it. If you want to experiment and enjoy the learning hands on experience this could be a great project. If your ultimate goal is the vehicle than looking at existing ones is very viable.


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