Have you considered the heat that would be generated to go over 22 hp and how fast you would drain the battery? I have found ev at 40 going down a slight grade to be the best use for me of the ev mode. I usually use the ice to climb the hills and the ev to go down.

 

Like gpsman, I have been able to go into electric drive at speeds of 60-65 mph under rare circumstances, at least according to the nav screen in my 2008 MMH. This has always been in circumstances in the mountains where I have just coasted down a long hill, and the battery is "overfull." I do not have a Scanguage to know the exact SoC, but the battery icon is completely green (even above usual +/- marking), which I think corresponds to a SoC of greater than the usual maximum 60%. I have always thought that this was a way for the battery to deplete itself back to its normal upper limit, so as to allow further regen. The engine is still turning with an rpm of about 1000, but the nav screen is showing a pure electric drive. So, to my mind, this seems to be a software, rather than a hardware issue, as the electric drive components seem to be able to propel the vehicle at high speeds successfully under the right circumstances.

 

I understand it would drain the battery faster, but I was thinking of this only in a phev with higher capacity. I would like to be able to just drive in EV mode, and speed and efficiency or rapid consumption of the battery would be ok.

Let me ask you this, what would happen if you ran out of gas and the ice couldnt kick in ? would the computer intervene or would the system think the ICE is running when it wasnt and we would find the true limits of the EV mode power.

 

OK, I think some definition is in order here. I consider "EV" to be when the ICE is not spinning. This would not include those times when the RPM is at 1000; even though the engine is not using gas, it IS using electricity to keep it spinning. BTW I have seen the engine spin @ 1000 RPM up to around 65 miles per hour - it just depends on the down hill slope.

In EV mode, there is no extra energy required to spin the engine.

 

The FEH can travel up to 40 miles per hour in EV mode. I remember reading that this was to prevent damage to part of the powertrain, I believe the transmission. I can only go EV at 40 miles per hour when slowing from a faster speed or going down hill, but I have routinely gone from a dead stop to 31/32 miles per hour in EV mode. The 2008 Sourcebook does state that it "can run on electric power only up 25 miles per hour."

 

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This is one photo of what you might see on a scanguage going down a long hill. Note the State of Charge (SOC) is 68.6 and 1440 AMP-amps going into the hybrid battery to raise the SOC. I took this last January during a drive into Maryland when I was out for a ski outing.

 

To clarify, due to the 2's compliment formula and how it works with negative numbers, 1440 = about 5 amps going into the battery.

Still, 5 amps x 350 typical volts = 1750 watts of charge.