Well, I have a 2013 SL that I leased at the end of March 2013, so 2 summers. I live in San Dimas, CA, so somewhat hot here in the summer, but nothing like Phoenix. I'm now just shy of 24,000 miles, and just lost my first capacity bar yesterday.
For the first 20 months or so, I pretty much charged to 80% for my commute (48 miles round trip), and to 100% probably a couple times a week when I needed additional range. The car is garaged when at home, but did have to sit outside on blacktop at my office in Anaheim on the days I was in the office (average 2-3 days/week). I have a lifetime average of 4.4 mi./Kwh.
When I first took a LeafSpy reading in June 2014 (about 15 months after leasing) with 14,350 miles, I had a SOH of 97%. Now, less than 10,000 miles and 11 months later, I have a SOH of 84%. So, it held up very well for the first year plus, then a pretty steady decline over the course of the last 11 months. That second summer really had a significant effect.
Here's my original screenshot from June of last year:
And here is a link to the new one (notice no additional QC's):
https://www.amazon.com/clouddrive/s...ageBxrsPGFbNEPMs7_tcM?ref_=cd_share_link_copy
From a 100% charge, I can still get roughly 75 miles out of the battery until VLBW if I'm very careful, so not too bad. But definitely a noticeable drop in range from new. I'm a bit concerned about what's going to happen throughout and after this coming summer. I guess I'll see.
I really do enjoy driving electric, but I'm thinking that the Leaf just went about it the wrong way with no thermal control system on the battery. I see a lot of Volt owners with 2011's still getting 50 miles/charge after four years - probably a combination of a good thermal management system, and the overall percentage of capacity that is available for driving in a Volt. At any rate, with 50 'rated' miles in the 2016 Volt (and probably closer to 60 miles actual), I'm think that the 2016 Volt might be my next car when I turn in my Leaf next March. With the quick capacity degradation and the used values of Leafs, I'm just glad I leased and didn't buy this time around.