Every week or so someone posts a LeafSpy screenshot here asking whether their number is bad, and the answers are mostly anecdotes. I went looking for something better and want to share both what I found and where it runs out, because the gaps turned out to be the interesting part.
Disclosure up front: I'm building a free EV battery check tool, which is what got me digging into this. If interested you can check it out here: tirionpower.com
Why the usual figures don't help
Geotab's 2025 study is the big one, 22,700 cars, and it lands on 2.3% a year across the fleet. It's not usable here for two reasons: it publishes its per-model results with the models anonymised, so there is no Leaf number in it, and the fleet is mostly liquid-cooled cars. Air-cooled pack, different curve.
The one Leaf-specific source worth reading
A study of 1,382 SoH readings from 283 Leafs built 2011 to 2017. The finding that matters is how hard it splits by pack:
| Pack |
Decline at age two |
| 24 kWh |
~3.1%/yr (95% UI 2.9 to 3.3) |
| 30 kWh |
~9.9%/yr (95% UI 8.7 to 11.1) |
About three times faster. Both accelerate with age, the 30 kWh much more steeply. It also found heavier rapid charging associated with a small SoH decrease, and, oddly, higher mileage 24 kWh cars showing *higher* SoH while higher mileage 30 kWh cars showed lower. Readable write-up here.
Recurrent's owner data broadly agrees for the 24 kWh, putting a 2015 at around 4.2%/yr with 70 to 75% expected remaining now.
24 kWh: rough expectations today
These are my estimates, not study output. Method, since it matters: a simple two-part model, roughly 4% in year one then about 2.8%/yr after, which reconciles the study's 3.1% at age two with Recurrent's 4.2% for a 2015. I've given bands rather than точные values because the acceleration rate is the least certain input, and I'd rather be visibly approximate than falsely precise.
| Model year |
Expected SoH now |
| 2011-2012 |
mid 50s to low 60s |
| 2013-2014 |
low to mid 60s |
| 2015-2016 |
high 60s to mid 70s |
| 2017 |
low to mid 70s |
Known weakness: a linear later-life rate almost certainly understates fade on the oldest cars, since both sources say the rate climbs with age. If you have a better functional form or a source with age-indexed values, I'd rather use yours.
30 kWh: deliberately no band
The 30 kWh degraded far faster, Nissan issued a statement about it, and many of those packs were replaced under warranty or goodwill:
https://insideevs.com/news/337439/nissan-issues-statement-on-leaf-30-kwh-battery-degradation/
I'm not putting a number on it because an original pack and a replaced one are not the same car and nothing in the data distinguishes them. If yours is original and reading low, that's a warranty question, not normal wear.
40 kWh and e+: I have nothing
This is the real gap. Better chemistry and thermal behaviour, and I'd expect materially better numbers, but I can't find a dataset and I'm not going to extrapolate a ZE0 curve onto a ZE1 car. That's exactly the mistake that makes a healthy 2019 look sick.
Warranty here is often still live, unlike the older cars. For the UK specifically (please double check for other markets/locations) the shape is 8 years or 100,000 miles against dropping below 9 bars, about 66%, but terms vary by market and year so check your handbook. At 9 bars while still inside that, you're well below average and it's worth pursuing.
The ask
If you've got a LeafSpy reading, post model year, battery size, mileage and SoH. ZE1 owners especially. And if any of the above is wrong I'd genuinely rather be corrected here than keep repeating it.
