Magneto-not The Kevin Bacon

[Garbone]

Looks like Jeep is floating a BEV.

https://www.thestreet.com/investing/jeep-has-a-big-surprise-for-ford-gm-and-rivian

Very interesting,. I wonder if Ford will be far behind.

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[Itchysquatch]

Have to admit this has definitely peaked my interest. They kept the 6 speed!! Amazing. Benefit of auto off road, and manual on. I hope they do develop this, and ford, toyota etc follows. They need to switch up the batteries to next gen (solid state etc) to get a better range though.

 

[FastAndLight]

The power numbers on that are really low compared to most electric vehicles. Everything about that sounds like the worst of both worlds. I get liking to shift on your own (both of my daily drivers are sticks)...but in an electric car its just more work for no good reason. The engine won't stall. The torque comes on from 0 RPM. The powerband is generally very very broad compared to a ICE motor and is exceptionally linear. There is no real need for a clutch, and only limited use cases for a transmission at all. The transmission has to be one of the most complex parts on a vehicle. Why would engineers seriously consider adding one to a vehicle that does not need it....I have so many more questions...

 

[HorizonHunter]

The power numbers on that are really low compared to most electric vehicles. Everything about that sounds like the worst of both worlds. I get liking to shift on your own (both of my daily drivers are sticks)...but in an electric car its just more work for no good reason. The engine won't stall. The torque comes on from 0 RPM. The powerband is generally very very broad compared to a ICE motor and is exceptionally linear. There is no real need for a clutch, and only limited use cases for a transmission at all. The transmission has to be one of the most complex parts on a vehicle. Why would engineers seriously consider adding one to a vehicle that does not need it....I have so many more questions...

Even if power delivery is linear, wouldn't the manual offer more fine control? So if you smash the throttle in first gear, the gear ratio would keep you from spinning too fast?

 

[FastAndLight]

Even if power delivery is linear, wouldn't the manual offer more fine control? So if you smash the throttle in first gear, the gear ratio would keep you from spinning too fast?

I'm not an automotive engineer, but I think the answer is no, and that starting in first would only make things worse from a slippage perspective.
Electric motors (generally) develop almost all of their max torque from 0 RPMs. Not quite the exact opposite of a ICE motor, but very different.
In your example, mashing the gas from "idle" (0 RPMs) with the maximum reduction (1st gear), means that potentially all of your electric torque, and all gear reduction, are applied. I think in most cases this would overwhelm the available grip, and you would spin your wheels. You might want to start in 6th and work yourself down until you can move the vehicle under control without wheelspin.

I think to really enjoy offroading in an electric vehicle, you would want the ultimate traction control system monitoring the wheel slip compared to vehicle speed for each wheel (or axle), and then adjusting the torque applied as necessary to limit slip. You would probably also want speed-sensitive pedal mapping to give you a lot of room to make small adjustments with the throttle. If you watch Demuro's video of off-roading the R-1T you can see how difficult this is to get right in a 4 motor setup:

Granted his situation is a hill with loose rocks and stuff, but I imagine in a lot of situations the problem is gaining traction, not having too little torque to move the vehicle.
It looks like a single electric motor can generate more torque than the traction a given wheel / tire can produce. This likely applies for axles as well in a dual motor setup.

Basically, you don't need a transmission for slow speed off-road. It would just be one more thing to mess with. With an electric vehicle, since for many designs torque falls off with increasing RPM, a transmission would really only be useful at high speed, where you also need high torque. This may be why Porsche includes a 2 speed automatic transmission on their Taycan electric sports car. I imagine being on a high speed track you may want to lower the motor RPMs for torque, heat, and other reasons.

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