Any of you guys who have been around the block so to speak with the Leaf want to weigh in on these number and my thought process?
Here's my most recent reading on my 2015 S with 18,400 mi. MFG 4/14.
283 Gids
21.93 Kwh
97.28% SOC
90.62 SOH
92.60 HX
60.04 AHr
77 degrees average temp
My numbers have kind of been all over the place with my 2015 and I'm trying to make sense of them. When new I had 292 Gids 97% SOH, 63 Ahr. During the first winter the numbers dropped, I was getting anywhere from 278-284 Gids, As low as 89% SOH, as low as 58.5 Ahr, Then during my second summer (at about 15K miles) with the car, numbers came back up and I was averaging about 284-289 Gids, 92.5% SOH, 94.5 HX, and 61.3 Ahr, now at the tail end of summer/early fall, I'm tracking the numbers above. I'm trying to understand what's going on, but the best I can summarize, the only thing to look at is a moving average. Numbers rise in Summer, drop in winter, etc...
Here's my best guess, perhaps you can confirm or deny.
1. There was some unused capacity above 292 Gids that was being degraded from Day 1, I've probably blown through that at this point.
2. The SOH, Ahr, HX numbers are somehow connect to how the car is used, charged, temp, etc.. because they bounce around.
3. The best way to estimate true degradation rates is to look at the pack from the time it just starting falling off 292 Gids (no more hidden capacity).
4. My Gids loss demonstrates from new demonstrates about a 3% capacity loss from when new, but my AHR shows about a 5% loss. Can I then assume that there's been about 2% of hidden battery capacity loss?
5. If I look at a moving average, it may tell me a better story of capacity loss in the coming years/miles. My guess is that I've experienced about 5.5% real loss at this point, (3% realized in Gids), but I can expect roughly 5% or so for every 18K miles from this point forward. Meaning that I'll be at about 36K miles, I'll be lucky to get 270 max Gids, and at 54K miles, I'll be at about 255 Gids.
6. If I lose Bar #1 at the same point as earlier cars, this will mean that I'll drop it somewhere around 60K miles give or take?
I suppose I shouldn't be too upset about this. A loss of 5% capacity per year is better than most early Leaf's but I'm just trying to get a jump on when to sell the car and move on with another EV. So much at play here including waiting for the Tesla 3, expiring tax waivers, etc... I'd like to be able to transition to a two car EV/Plug In household while there's still federal tax credits. This will means selling my Leaf and our two ICE cars within 2 years time for a Volt/Tesla 3
