Texas Ranger

Thanks for all of your information. I decided to purchase a 2013 Fusion Hybrid, not the Energi. I don't see documents indicating that there is any liquid cooling. I believe that the pack is air cooled and will use ambient air from the cabin. I do not know how much heat energy is dissipated this way. My 2013 will cruise at freeway speeds (<63 MPH) for a while, so I believe that the energy consumption would warm up the High Voltage battery pack at this condition. I'm just guessing that most of us will not drive a car un-air conditioned at very high temps, so this may not be an issue (the cabin air temp at the human comfort level is low enough to provide heat transfer away from the HV battery.) I'm hoping that's correct - or that the Blue Oval engineers have a high-temp shutdown feature to save the battery if it encounters extreme temperatures. That being said, it's really cool to coast in EV mode at freeway speeds! :)

I'm a member of the Houston Electric Automobile Association and Ford did a presentation of the C-Max and Focus Electric at last night's meeting. (I got to drive the C-Max.) Ford is apparently well aware of this issue. The presenters said that the battery pack has "active temperature control" for the pack. For hot climates, the pack has fluid cooling - and in cold climates the fluid is heated. This uses a little power, but preserves the life of the battery better. Like all devices, the battery will not last forever - but my Fusion Hybrid shows no real degradation after 3 years and 70K miles. I trust them. One 'feature' that they mentioned is Ford's recommendation to have 20% battery if the car is stored for 1 month - and 50% if it is stored for 6 months (plus disconnect the 12VDC battery.) I think I have the numbers right. This doesn't seem much different than filling the tank when storing a car - to prevent moisture accumulating in the tank. They didn't seem to have any concern about storage in hot climates, as long as proper precautions are taken.

I understand that the Volt does not this problem. By source says the problem comes from not having liquid cooling. In hot climates the vehicles with only air battery cooling have more degradation. I assume that Ford has liquid battery pack cooling but don't know this for sure.

The following site is something that appears to plague the Leaf (and Volt) in hot climates like Phoenix, AZ or Conroe, TX (my town.) http://www.mynissanl...y_Capacity_Loss I know that Ford has improved the battery manufacturing, but I don't know if the chemistry for the Energi is LiFePO4. If so, does anyone have information about Ford's hot weather testing of the Energi or new Hybrid battery pack? I understand that the previous Ford battery chemistry was NiCad which is more tolerant to 100+ degree days. I'm sold on the idea of the Energi, just need some tech data on hot climates.