Originally Posted by David Lee

I spend a considerable amount of time driving up and down in the mountains and I'm trying to determine how well, or how different the Escape Hybrid will operate in that environment.

VERY WELL if you are gentle on the uphill, and do a lot of "coasting" on the downhill... ie. let gravity do most of the work and don't use a lot of gas pedal to speed up on the downgrade... let speeds flutter 5 or 10 miles per hour above and below the posted speed limit. Keep load ( or RPM ) constant, and let speed fluctuate.

Concerning the charging of the batteries.
What tells the system to charge the batteries? Just stepping on the brakes?

Several different inputs, probably 2 dozen, are used to determine when to charge/discharge the batteries.

The Escape brochure does not specify as I recall that the ICE will run to recharge the batteries if they are low though various other sources alude to this. What is the real story?

The gas engine will run to specifically charge the battery, if the chrage is very low. This almost never happens. Usually, the engine will come on to keep the catalyist at optimum temperature to reduce emissions before the battery gets that low. So while it's keeping things "hot" it is also re-charging, if needed. 5 minutes of engine off at 65'F will cool things enough to evoke engine re-start, ( for 30 seconds ) but few of us have red lights longer than 5 minutes.


Is the electric motor spinning all the time (like say a flywheel)? As dead weight unless told by its controller to act as a generator or as a motor.

In short, YES!

If an Escape was on a long downhill pass, (such as Donner Pass, Highway 80 between Sacramento and Reno) is the transmission capable of downshifting to slow the downhill speed?

Yes and No. It will spin the motors and/or engine at higher RPM to create resistance, yes, but there is no "downshifting" as this car ( ie. transmission) does not shift... EVER!

If so is the electric motor providing some of the resistance and charging the batteries?

Yes, to a point. 2-3 minutes/miles of contstant downgrade will have the batteries at maximum charge.

If so, what if the batteries are charged or become charged while on the way downhill, is the resistance now less in the downshift mode?

Again, not a simple answer. If the battery pack is fully charged, the wheels will spin the large motor to act as a generator and create drag.
The wattage from the motor/generator will be sent to the smaller starter motor/generator. The smaller starter motor will consume the wattage by spinning the gas engine at about 4,000 RPM. This combined action very cleverly re-creates the same amount of slowing that a conventional low gear would. Again, this car cannot really "change gears". Oh... even though your gas engine is spinning at 4,000 RPM, you will get upwards if 200 MPG during these downhill sections. No gas needs to be consumed ( or very little ) since the electrics are doing all the "work". Again, very clever design!

If the batteries are fully charged is there a load bank (like in a locomotive) that continues to provide some resistance such that your not slowing down by friction only?

No, but this was explained above.

Is some braking required on a long downhill to convince the system to use regenitive braking?

No, if your speed increases by gravity with your foot off the gas, mild regeneration will occur automatically.

For what it's worth, the electictric motor acting as a generator provides up to 50% of your braking effort. Thus your brake pads are used 50% less often, and/or 50% less strongly than a traditional car, and should last at least twice as long. You do however have 4 wheel disc brakes, that can provide 100% of your braking in emergency conditions.

I think that covers it and I'm being told to get to the dinner table.

Thank you for your help

David Lee