Heavy Air Conditioning Use and Battery Life

Heavy Air Conditioning Use and Battery Life

Let me start out by saying that I know this is an unfair question to those who are in the depth of winter, but it has been almost 80 degrees here in Phoenix.

It has been my experience that car batteries in Phoenix never last and I have been told that it is primarily due to the heavy use of the charging systems powering the AC. I know that there have been issues with cold weather mileage and I was wondering if there is any information about how 115 degree weather and constant AC use will affect mileage as well as the life time of the batteries.

I typically commute a total of 70 miles per day which means that the 40 should be enough to go to work and back but I am concerned that with real world driving conditions (80 mph driving, AC running) coupled with decrease in battery capacity will result in less than 70 mile range in a few years.

Ive tried to look through past threads for info, how come there is no search capability?


petero | January 24, 2013

Most of us use the following as our 'official' search engine.

jat | January 24, 2013

The AC seems to draw about 1.5kW while it is on, so unless you are just sitting stopped with the AC on for hours, it shouldn't have a large impact on your range. The unknown about battery degradation would seem more problematic for your use-case. Even though Tesla uses more active control of the battery temperature, the LEAFs that have had excessive battery degradation were all in hot climates like Phoenix.

Brian H | January 24, 2013

What the volkerize page does, you can do with any search engine by including a site: specification in the search box. In this case, restricts the results to this forum. But of course it works with any target site. would include the entire TM site, e.g.

fluxemag | January 24, 2013

The Leaf doesn't have active cooling, that's one reason I didn't buy it for my wife. It's really not made for this climate, although it will work. I have seen Leaf forums where they have battery temp warnings due to the climate in Phoenix. I also live in Phoenix. My concern is how will the battery cooling work when parked at the office? If the car sits baking in the desert sun for 8 hours, the batteries are either cooking too, or the batteries are draining to cool themselves. I would hate to come out with not enough range to get home. We are working on getting a charging station put in. That combined with the proposed smartphone app would allow me to pre-cool the car before I head downstairs.

gregv64 | January 24, 2013

My understanding is that battery temperature really only matters when the battery is being charged or drained, not just sitting there. Somebody who knows more can correct me if I'm wrong.

Brian H | January 24, 2013

even a 120V would enable the battery to cover its cooling "costs", I think.

rapnjoe | June 16, 2013

Lithium Batteries are best to be maintained at a state of charge between 20% and 80% and if you live in a place like Arizona that gets extremely Hot, you should not charge the batteries to 100% if your EV will be parked in the extreme heat all day, the best state of charge when in extreme heat is 50% and this seems to work out well for me since when I drive to work my Batteries are usually between 45% and 60% state of charge. With Tesla' active thermal cooling this may not be an issue but just for added peace of mind I will still try to plan on having a 45% to 75% state of charge if my EV must be parked outside in a hot parking lot all day.