I am currently collecting data from other Gen...uh...4? LEAFers with 40 and 62 kwh packs for a more balanced analysis of what we can expect to see long term. Before 2018, I didn't have much interest since it wasn't till then that I wanted to keep any LEAF long term. Even the bullet proof 30 kwh pack I had was only a considered cheap transportation purchase to use later to trade up. But despite the fact the 40 kwh had the range I would need, it didn't have the buffer to allow better charge management which is why I am driving the Plus now.
A New BMS
Starting with the 40 kwh packs, we started seeing large adjustments in pack numbers via LEAF Spy every 3 months. I still don't have enough data to tell you where we will be in 5 years but the early patterns are quite consistent among drivers with various needs, living in vastly different climates experiencing various driving conditions. The "climate" factor so well published including a Gen One degradation prediction chart based on one's city (quite accurate actually) simply didn't work. We have people in VERY hot areas performing very well comparatively with others in mild climates that normally favor batteries by a large margin.
Adjustments; Phase One
Although there seems to be outliers, the vast majority of us are seeing rapid drops in numbers lasting 9-15 months. 7 to 10% loss during this time is normal and covers over 90% of people who bothered to submit their battery stats. My pack was no different. Not only was I losing chunks on my adjustment, I was also seeing a decline of .01 or .02% 4-7 times a week. "That" alone can add up to over 2% annually. Hx is almost always skyrocketing here. There have been a handful of people whose Hx has remained "reasonable" lower than 110% and all of them (keep in mind my "all" is a very small list due to people not posting their stats when ASKED!) were slightly above the curve.
Adjustments; Phase Two
But the big chunks don't last. A new pattern emerges where the chunks lost in many cases, become chunks gained. Now we need to understand that realistically, this isn't possible but the circumstances of how these increases happen doesn't really allow us to blame instrumentation like the 24/30 kwh packs which bounced up and down on a near daily basis. So a huge number saw their numbers go up, others saw their adjustments get MUCH smaller or simply stop happening. My guess is the adjustments are still there but have nothing to report. I also have daily records kept; something few others do.
Adjustments; Phase Three??
Now, my Plus has only been in Phase 3 (I call it and...pretty much only I do) for just over a month. In Phase 3, the downward trickle slows considerably. Instead of seeing the .01 or .02% adjustments almost daily, they drop to almost once a week. In the chart below, to reduce the noise I only recorded ahr/SOH when the value changed. Notice the Hx is also on the slow decline? My adjustment happened during this period with a loss of .37%
Notes; I have been on a SOC control kick. Since I don't have NCTC any more, I have all but avoided DC charging for the most part and "maybe" that is contributing to the very slow numbers decline. I am running between 20-45% mostly with a few bumps to 65%. Although it doesn't show here, the longest day during the slow decline was 118 miles. Another thing to consider is I am simply not driving all that much. With the new restrictions put in this week, it will be even less. I am guessing neither the miles driven or lack of DC charging is a "significant" factor. Below is my 40 kwh @ 15 months
Notes; Full on Summer here and all the public charging is DC since I had NCTC at this time which is why I didn't break out separate columns for DC and AC. Unlike my Plus, I BAKED the 40 several times. Free charging does that to me and it was also during a time when Central WA was blowing up with new stations so trips to Ellensburg and Yakima were a must. Yakima was during Summer and it was HOT! Leaving there, I took White Pass back to Centralia Webasto; a 162 mile trip which is quite the challenge on flat ground. This meant charging on DC (it was free for the opening!) until it stopped at 98% and topping off at an L2 in town; all done at near 100º heat. Fun times!
Point of comparison; One year
2018 LEAF; 16,134.5 miles SOH 92.99%
Plus; 14,669.5 miles SOH; 93.13%
Factor in the mileage difference and its all but a dead heat. This is shocking to me. The charging/driving habits were as different as different can be. In the first year, my 2018 had a diet of 87% DC, My Plus only 55% DC with nothing since August 24th. The smaller pack charged to a higher level. I had 30 mins free so frequently charged until it stopped. So my SOC was higher, my pack a LOT hotter.
Now the Plus has not done the road trips I had planned. The real test was going to be a rafting trip in Central OR followed by a visit to Bend OR then swinging back up thru Central WA back to Olympia in the dead of Summer but COVID derailed those plans. The additional range along with the fact the pack doesn't heat up enough on the first charge made hitting 110º quite the challenge. My only experience with Rapidgate was during a run when leaving home under 10% SOC. I stopped in Castle Rock charging only 20 mins which was more than enough to get me where I was going in time (barely) then grabbed another 23 minute charge and went back to EA Lacey and charged at 55 KW when I normally would have seen about 73 KW. A slowdown? Yes... drastic? You decide.
Now we are in complete guess mode but based on the limited data submitted by other LEAFers over 2½ years on theirs, the trend is holding up. Below is two charts; the 2018 with 25,125 miles over 21 months then the Plus at just over a year. Data points taken every 1000 miles more or less (whatever the end of the day provided) and displays projected ahr/SOH @ 100,000 miles. The 2018 has a wiggle in it due to a LEAF Spy recalibration of the SOH.
To read the chart, you need to look at the drops and how they compare with the upward slopes between the drops. You can see over time, the drops become smaller and the upward slope becomes greater. This indicates the rate of degradation slowing.