I believe (but have no proof) that the FEH and MMH will do what ever they have to, to keep the battery at a comfortable (for lack of a better word) temperature.

Very cold and very hot batteries do not function well. That is why there is so much emphasis on thermal management for hybrid car batteries. Our cars 2005 to 2008 have deticated Air Conditioning lines that run to the battery pack. Just look under the driver side behind the rear wheel and under the vent for the battery pack. You will see two silver AC lines.

It seems that the 2008 FEH and MMH run @ 500rpm greater than the 2005-2007 FEH. I believe this is because people complained that the AC was not very effective near 100F.

Are there any 2005-2007 owners who can tell us their experience @ 100F?
Rick

Rick, thanks for the responce. My observations would tend to agree, but I really am only having huge issues (ICE running 10+ minutes before shutoff) when the temp is closer to 110+ degrees. It has been in the veyr high 90s or low 100s this whole week and my drive home has been normal. The ICE will shut off after only 2.5-3.5 minutes.

My car (for the most part):


My old car, now the new bride's car:

I want to post my stats from my current tank. I have driven about 215 miles in the last 13 days. I have driven from work to home (straight) 4 times - in the afternoon when it is hot. The stats look like this:

Temp/ICE Running Time before EV mode kicks in/Total Drive time/MPG

- 111/ 18*/ 39/ 36.9
- 107/ 10.5/ 35/ 38.7
- 107/ 13/ 33/ 41.1
- 101/ 2.5/ 33/ 41.9

As you can see with the heat - it is diretly porportinal to FE. * In fact on the 111 degree afternoon The ICE kicked into EV mode at about 12 minutes into the drive, but becuase I was hitting so many lights (see the drive time vs. a normal 34 minute drive) it actually kicked the ICE back on becuase it was getting so warm in the car.

I'm sorry I don't have more data, the past few days this week I've been running errands on the way home and stopping at my parents house to check on the cats and get the mail since they are out of town. I don't want thoes number to skew anything since they are different routes.

My car (for the most part):


My old car, now the new bride's car: