While EV batteries have generally proven to do better than the oil companies would like us all to believe, there’s still a lot of room for improvement (we’re looking at you Nissan!). On the other hand, the EV community has largely stumbled in the dark over battery life.

Until now, at least! Geotab just released data based on the observed real-world degradation of over 6,000 electric vehicles.

The good news: EV batteries are generally doing pretty good. Based on the data, Geotab tells us that the “vast majority” of electric vehicle batteries will outlast the rest of the vehicle. If this continues to hold (and it should), electric vehicles are poised to really prove themselves over the next few years.

The bad news: not all EVs are created equally. Some are doing far better than others, even when driven the same, used the same, and living in the same climates. As many LEAF owners already know, the biggest thing that’s making the difference is cooling. Vehicles without a good temperature management system for the pack don’t do as well as those that have one.

You can create your own charts here.

Speaking of temperature, vehicles that live in hotter climates don’t tend to do as well as those in more moderate environments. Even with a good cooling system, the time spent sitting in the heat when the vehicle is not on doesn’t do it any favors.

Speed and state of charge are also proving to be a big factor. For example, they show that vehicles doing more “Level 3” rapid charging tend to degrade much faster than those using slower methods more. Also, keeping the battery between 20% and 80% (like the Chevrolet Volts did) has proven to minimize degradation.

The great thing about this emerging pool of real world knowledge is that future vehicles and vehicles we refurbish will benefit. By refurbishing your Nissan LEAF’s battery system in 2020 and beyond, you’ll get the advantages of newer EVs without giving up the low price of keeping your existing 2011-2016 vehicle.