# Outlander Rear motor with diff



## miniswift (Mar 16, 2020)

Hi, 

This is my first post so be gentle with me....
Spec says that it is 30Kw but max 70Kw and torque is 195Nm.


My question is simple...
In standard Outlander, tyre is 255/55-18 which has tyre diameter of 705mm.
If I am to fit this setup in my classic Mini with 165/70-10. It will have 485 diameter.
Weight of car will be 1/3 so I hope range will increase but due to tyre to be 68% of original, theoretically speaking... what will be 13.8Kw will do?


Nissan will soon be making a Qashqai with Outlander PHEV technology.
So I'm hoping we will have cheaper battery and rear motor setup soon.


Cheers
Atchi


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## brian_ (Feb 7, 2017)

miniswift said:


> Spec says that it is 30Kw but max 70Kw and torque is 195Nm.


Where are you getting the specs? Everything I've seen from Mitsubishi just says 60 kW for the front motor and both motors pre-2019, and 70 kW for the rear motor starting in 2019, with no distinction between continuous and maximum ratings.



miniswift said:


> My question is simple...
> In standard Outlander, tyre is 255/55-18 which has tyre diameter of 705mm.
> If I am to fit this setup in my classic Mini with 165/70-10. It will have 485 diameter.


The difference in overall tire diameter will change the motor speed for a given road speed. That doesn't by itself change the available power, but you will be operating the motor at a different point in its speed range. If the Outlander design is like other modern EVs, the motor is 

limited to a fixed current (and therefore torque) up to some set speed at which the product of torque and speed is the rated power, 
then above that it is limited to a fixed power level (not by the motor, but by controller programming) until close to the motor's maximum speed,
then the power drops off due to the limitation of available battery voltage up to the maximum speed.
195 Nm corresponds to 60 kW at about 2950 RPM and 70 kW at about 3440 RPM, so the first constant-torque range probably goes up to somewhere in that range. I don't know what the Outlander rear unit's gear ratio is, but in the similar i-MiEV it is about 7:1 (motor:axle); if the Outlander has the same ratio (I wouldn't be surprised by more reduction), then this transition from torque-limited to power-limited would start at about 420 wheel rpm... that's roughly 56 km/h for the Outlander's tires, and 38 km/h for the Mini's tires.

With the assumed 7:1 ratio and the big Outlander tires that peak torque corresponds to about 3.9 kN of drive force, so acceleration of two tons of Outlander would be leisurely (less than 2 m/s² or 0.2 g) with only the rear motor. Assuming the same peak torque and ratio, the little Mini tires would result in 5.6 kN and a much more pleasing acceleration of one ton of Mini of up to 5 m/s² or 0.5 g... at low speeds.

The other obvious result of the tire diameter is that the maximum speed of the vehicle, limited by the maximum speed of the motor (or the speed at which the motor can produce enough power) is also reduced, again roughly by the tire size ratio, so a 30% reduction. I've seen various values for the Outlander's maximum (presumably motor speed limited) top speed; using 170 km/h (published for the 2019), that would correspond to 117 km/h. That seems fast enough for a DIY converted original-style Mini to me.  On the other hand, the 170 km/h speed may only be possible with the gas engine; in EV mode the 2019 Outlander PHEV is limited to 135 km/h, which may correspond to the highest speed at which the battery voltage is sufficient to produce useful power. If the Outlander limit is 135 km/h, the Mini limit would be only 93 km/h... maybe still enough.



miniswift said:


> Weight of car will be 1/3 so I hope range will increase but due to tyre to be 68% of original, theoretically speaking... what will be 13.8Kw will do?


I suppose the question seems simple. That answer... not so much. 

You presumably meant to ask "what will be _the range which_ 13.8 *kWh* will do?"
The only dependence of the range on motor speed is due to motor and inverter efficiency, which varies with speed and load. That's usually best at a moderate speed and relatively high load; I would guess that in the Mini the motor will be operating at a lower-efficiency point than in the Outlander, but that's only a guess.

So I wouldn't worry to much about the tire diameter effect on range. The range (for any EV) is the available energy divided by the energy consumption per distance travelled. One would reasonably hope for lower consumption by the Mini due to lower rolling resistance (due to less weight), lower aero drag (due to less frontal area), and less energy used to accelerate and only partially recovered in regenerative braking (due to lower mass). Unfortunately, the Mini's random aero form will hurt that to some extent.

If you're considering the Outlander PHEV battery for this conversion, I'll note that before the 2019 model year the battery capacity is 12 kWh... and 13.8 kWh for the new version, which also has higher motor output. A DIY conversion would typically use salvaged parts from an older vehicle.



miniswift said:


> Nissan will soon be making a Qashqai with Outlander PHEV technology.
> So I'm hoping we will have cheaper battery and rear motor setup soon.


I doubt that either will get cheaper. Battery cost depends on capacity, and they are unlikely to use much less than 12 kWh of battery in a plug-in vehicle; the motor is about the same as the one in the i-MiEV, and much smaller wouldn't provide adequate performance even in the lighter Qashqai. Also, even if the Qashqai motor is cheaper, if the reduced cost is due to being smaller it won't be desirable as the only motor for even a Mini.

I had not heard of this plan from Nissan so I did some searching. Apparently the Qashqai is built on Renault-Nissan-Mitsubishi Alliance's CMF-C/D platform for mid-sized and large vehicles; the current (third-generation) Outlander is not, but the next one is expected to be. Since the point of a platform is to use common bits, the PHEV bits for CMF-C/D will presumably be about Outlander-sized, and any cost saving will come only from larger-scale production.

For an additional complication, the published speculation about the Qashqai hybrid includes both Nissan's ePower design and Mitsubishi's design (as used in the Outlander PHEV), with speculation that it will be one, or the other, or both available. If both, the ePower would be a non-plug-in, while the Outlander's system would be used for a plug-in. ePower is a series hybrid like the Outlander PHEV, but without the Outlander's direct mechanical drive at highway speed (relevant only to the front drive which wouldn't be used in this conversion) and so far only as a 2WD (so, no rear motor unit at all).


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## miniswift (Mar 16, 2020)

Outlander can travel at 83mph with electric motor only.
So that will 132.8km/h


Thank you for your explanations. Very helpful.


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## miniswift (Mar 16, 2020)

brian_ said:


> 195 Nm corresponds to 60 kW at about 2950 RPM and 70 kW at about 3440 RPM, so the first constant-torque range probably goes up to somewhere in that range. I don't know what the Outlander rear unit's gear ratio is, but in the similar i-MiEV it is about 7:1 (motor:axle); if the Outlander has the same ratio (I wouldn't be surprised by more reduction), then this transition from torque-limited to power-limited would start at about 420 wheel rpm... that's roughly 56 km/h for the Outlander's tires, and 38 km/h for the Mini's tires.



I checked 83mph max with motor only.
With 225/55-18, (83x1.6)/60=2.2133km/m
2.2133x1000=2213.3m/m
2213.3x1000=2213300mm/m
2213300/(705xpie)=999rpm


So if you are saying 3440rpm for the motor, diff ratio could be 3.44:1


Did I calculate right?


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## brian_ (Feb 7, 2017)

miniswift said:


> I checked 83mph max with motor only.
> With 225/55-18, (83x1.6)/60=2.2133km/m
> 2.2133x1000=2213.3m/m
> 2213.3x1000=2213300mm/m
> ...


The calculations are correct (although using "m" for minute is really confusing ), so a wheel speed of about 1000 RPM at the electric-mode maximum speed looks right. But that should correspond to a motor speed of several thousand RPM, not 3440 RPM (the highest speed for torque-limited operation) but two to three times higher than that. One source lists 9300 RPM as the maximum speed of the Outlander motor, but electric-mode operation is probably limited to significantly lower than that. 

If, for instance, 9300 motor RPM corresponds to the 170 km/h vehicle speed limit (at which the wheel speed would be about 1280 RPM), the overall ratio would be 9300/1280 = 7.3:1. If 170 km/h does correspond to 9300 RPM, the the motor speed at 135 km/h (83 mph) would be 7385 RPM.

At this high speed, the motor would be producing much less than its peak torque, but at much higher speed so the available power would still be 70 kW.


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## miniswift (Mar 16, 2020)

Thanks Brian.


So in theory, I can do 70mph in my mini assuming 106mph is max speed with Outlander.


Mini is only 650kg as standard with a heavy cast iron engine approx 130Kg.
I think motor will be about 50Kg and batteries 100kg... I hope.


So without too much heavier, I can have EV Mini!?


NICE!


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## seanyt (Dec 14, 2015)

Hi All 
Just to add some information, 2019 model has 10kw more power because its battery is larger and can draw a greater current. rear motor is the same it seems. 

rear motor max rpm in an outlander is 9500rpm gearbox ratio is 7.065/1
im fitting one into the rear of a car as a hybrid 4wd system also still using the petrol engine up front.

I plan to use the stock inverter and keep it canbus controlled. So torque and power levels can be altered from what a stock mitsubishi phev ecu commands. 

Motor weight is also around 65kg. I put your top speed at 120km/h
Outlander also seems to limit top speed to 170km/h so it doesnt even reach max rpm. 

They also rate the EV losses at 15% for both its motors from battery power to axle power. 

But 200nm in a mini with such a small wheel size will certainly not be slow.


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## brian_ (Feb 7, 2017)

seanyt said:


> Just to add some information, 2019 model has 10kw more power because its battery is larger and can draw a greater current. rear motor is the same it seems.
> 
> rear motor max rpm in an outlander is 9500rpm gearbox ratio is 7.065/1
> im fitting one into the rear of a car as a hybrid 4wd system also still using the petrol engine up front.
> ...


Thanks 

Is that weight (about 65 kg) for just the motor, or the motor plus transaxle?

The limitation of power due to battery capability is probably common - the 80 kW and 110 kW Leaf configurations appear to have the same motor and change rating only due to battery, and even the 150 kW Leaf may be the same.


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## seanyt (Dec 14, 2015)

65kg for motor and gearbox. It's literally the lightest motor and final drive I have found. I think motor is about 40kg.

Exactly, same phase current just at a higher rpm. So the 200nm last a little longer before tapering off. 

Im running mine at 96s instead of 80s and plan to set torque demand at 250nm. 

I've seen the stock front inverter accept much higher torque demand than stock without issues. So rear should so the same. 

Also the miev motor used in the miev evolution has run 300nm and 100kw power with stock inverter.


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