leaftryer wrote:Is driving and parking the vehicle in the sun on very hot days a big problem for battery degredation or is it just a problem to charge the battery while it's very hot?
We get very hot and sunny summer days where I live and work, but I would normally be charging the battery during early morning hours after the battery cooled for several hours.
Even on the hottest days of the year where it may be 110 degrees at 4 or 5 PM and the car would be parked in the sun at work, I think the car would normally be only charging at about 3AM when the garage probably cooled to less than 90 degrees and the car would have been parked with battery cooling down for at least 6 hours.
Is there a reason why you haven't updated your location as requested? I can only guess Vegas from a post you made years ago.
The high pack temperature is likely big the issue but high SoC coupled w/high temps is even worse. L1 and L2 charging it makes it heat up slightly. Those are crazy temps. I've posted comments about Vegas and degradation before many times (e.g. viewtopic.php?f=27&t=19180&p=412699&hilit=vegas#p412699 and viewtopic.php?f=27&t=19906&p=426070&hilit=vegas#p426070).
Table 3 http://batteryuniversity.com/learn/arti ... _batteries has an example for a li-ion variant that may/may not be like the Leaf's.
Again, see my earlier post at viewtopic.php?p=499663#p499663 contrasting crazy hot Phoenix vs. mild Pacific NW.
GerryAZ in Phoenix has commented on his '15 lizard pack vs. '11 at viewtopic.php?f=27&t=24209&p=499021&hilit=bars#p499021. I don't follow his charging habits. http://www.electricvehiclewiki.com/Batt ... y_Behavior is supposedly the table of what each bar represents.
As I mentioned, it seems like the 30 kWh packs are not holding up well at all. I don't follow closely but from my quick observations and anecdotal reports I hear, they seem to be doing much worse than '15 lizard packs and maybe even worse than 4/2013+ '13 packs.
The pack has a lot of thermal mass and it takes awhile for it to reach/adjust to ambient temp. Your pack temps will likely be crazy high from parking outside at work in the sun at 110 F. To cool to "less than 90" probably means the pack won't even get down to 90 F before the cycle starts again.
To help preserve my battery on hotter days (above 85 F or so) at work, I try to find spots in the slightly underground section of work's parking garage where it sometimes doesn't even rise to 70 F down there on hot days. If they're full, I park at a far away building's underground garage and charge there. It tends to stay below 80 F there, even if it's 95+ outside. I can go there to grab my car at 5 pm and find the pack temp is below 80 F.
When I get home, I leave my car parked outside my garage for many hours before driving it in. It's cooler outside (e.g. in summer, it could get down to say high 50s or mid-60s) than my garage. It's nowhere near enough time to get the pack to reach ambient temp though.
If I wanted it to cool down further, it'd be best to leave it out overnight but I don't wish to do that work days as it might give clues to burglars as to when I leave for work. My house was broken into a few years ago.