GOM for Range Extender should not decrease

[CanisLupus]

For those of us with Rex models we have 2 GOM readings . One for the Battery (same as BEV) and another for the Rex . Even though the Battery GOM decreases along with reduced BATT.KAPA.MAX , I think that the Rex GOM should not lose as much expected range . Let me know what you think .

 

[jadnashuanh]

I think you're wrong for the following reason. Like any combustion engine, when you stress it higher (i.e., run it at higher revs), it uses more fuel. So, just like when driving along at various speeds with the electric motor, when you're really stressing things, the REx will have to run faster/harder to keep up, so yes, it will use more fuel, and thus, you'll get less range. If the REx only ran at one speed, it might be more consistent, but it is not designed to recharge the batteries higher than when it originally activated.

The EPA ranges are based on a very specific test sequence that often doesn't match any individual's use.

 

[JohnKelly]

The REX cannot do anything but supply electricity to the battery. It is the battery that supplies the range and also slowly loses efficiency over time, so the REX should show a diminished range as the battery gets less efficient. If the REX drove the wheels you would be correct, but it does not.

 

[nickp]

Actually in my experience, the Rex while going down along with battery in range, does show a much higher range when it actually switches to Rex. For example, driving in Battery mode the Rex might show 64 miles but when I actually shift to Rex, it goes up to show me much more range available.
In short, I do not pay attention to the GOM!

 

[jadnashuanh]

Think of the estimated range in the same manner as that feature on some ICE vehicles...it makes assumptions about how you have driven, and that you'll continue to drive in the same manner. That may or may not be the case. Drive a distance at steady speeds on the interstate, then enter the city. FOr awhile, it will say you have more range until empty, but your MPG may have been nearly 30mpg on the highway, but now is less than 20 in stop and go traffic. The REx's rpm and on/off cycles change based on how you're driving and how much electricity it is trying to provide, just like any ICE used at different loads, and the efficiency (burn rate) will change.

 

[CanisLupus]

I think that I didn't make clear that what I was referring to is the long term battery capacity . For any given previous driving that the GOM uses for calculation , the older battery with a batt.kapa.max of 16.5 will show less range than a new battery with batt.kapa.max of 18.6 . But with the Rex , for any given amount of fuel in the tank , it should still be able to create very close to the same amount of energy . It would lose some efficiency over time due to it's own integral properties but that would not be dependant on the state of the traction battery .