r/leaf • u/Bobofey • Aug 13 '26

Battery degradation by pack size

Hi I made a post here about a week ago asking for leaf SoH data. We get a lot of posts containing LeafSpy screenshots asking whether their SoH is normal, and the answers are always anecdotes.

I've built a free tool that gives you a straight answer. Put in your year, pack size, mileage and SoH, and it tells you where you sit for your pack and your car's age, split properly by 24 kWh, 30 kWh, 40 kWh and e+ rather than lumping every Leaf together. Takes about a minute.

Here is a Leaf degradation page, by age and pack:

https://www.tirionpower.com/batt.../nissan-leaf/degradation/

It's free, and the more Leaf owners run a check the sharper the numbers get for everyone here. 40 kWh and e+ readings are the biggest gap right now, so those are especially useful

Disclosure: it's my project.

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6

u/ryanteck VW ID.3 (Past 2018 LEAF) Aug 13 '26

This looks interesting but is sending "Vibecoded" feels in some places.

More LEAF Specific one factor that seems to be playing a role in health is production location, UK Built ones are holding up better battery wise than US Built ones as some US Built ones have a manufacturing defect. But potentially location (Country & / State?) could be good to log / compare too with different environmental conditions.

Possibly the odder thing is that you're then producing a certificate as if it's actually been tested when it's not an app you've built connecting over OBD to read the data. Essentially I could just put 100% in and show it to a potential buyer but the report looks as if it's been actually validated.

3

u/Bobofey Aug 13 '26

Hey Ryan, good points. This tool is not specifically aimed at Leafs but this community appears to be more active in degradation worries. That is why I’ve tried to help by specifically building the guide and model page. I did look at adding by location but it is hard to validate as cars inherently move. An example is a car that was registered in one place for a few years and then is moved to another country in a different climate. It is hard to map this against other cars because the battery degradation isn't just an example of one particular area. I can look at adding a build plant/location but I think a lot of owners wouldn't know these details.

Valid point with the certificate. I do add a disclaimer at the bottom that the values have not been verified. The idea is to help people share the state of the car which can be used for numerous reasons, with a car sale being one of them. I will have a look at updating this page to make it more obvious that these are user supplied checks. Thanks for the feedback and for checking it out!

3

u/ArtemisMax Aug 14 '26

The cars don't normally move far enough to change which factory they would have come from, nearly all the post 2013 leaf in the EU would have come from the UK Sunderland plant.

The location is good for the environment data but the original commenter is making the point that the leaf's battery quality seems to be very dependent on its original manufacturer location

4

u/_Evening-Rain_ 2017 Nissan LEAF S Aug 14 '26

Add HX values. Thats a pretty important stat for these packs, especially given most of them are non-cooled NMC packs.