[WorldMaker]

The impression I have: The first couple generations of Leafs don't have active battery temperature management and so far most Leafs that have entered the secondary market have done so in part because of large battery capacity reductions (necessitating in some of those cases battery replacements, which so far used dealers haven't been willing to finance at scale, so instead pass the "savings" to the next buyer).

As more Leafs show up with better managed battery lifetimes and/or as more used dealers get comfortable with battery replacements (and that gets subsequently cheaper as an industry), it may be likely that the Leaf loses its reputation as a "loss" on the secondary markets and maybe regains some of its resale value. (Especially now that current generations have more active battery management.)

But the entire secondary market for EVs is overall confused, because there are fewer EVs in the secondary market than should be. (The average first lifetime of an EV is way ahead of ICE "norms" right now, with average EV first owners keeping cars 7-10 years.) It may take used EV sales a while to better readjust prices to the actual marginal utility of a used EV (in light of overall reduced maintenance costs of a secondary EV lifetime versus ICE averages that used dealers have had decades of information about).

[m463]

After comparing leaf vs tesla I've come to a different opinion. It's not really battery temperature management, I think it's the small battery.

An older tesla with 250 miles range * 2000 cycles would have 500k mile lifetime.

An older leaf, 75 miles range * 2000 cycles = 150k miles lifetime.

Also, charge percentage vs battery health. Telsa recommends keeping the battery between 20 and 80% charge, and charging defaults to 80% (adjustable)

Leafs usually charge to 100% unless you poke around and find the 80% setting.

Note that keeping the leaf between 20 and 80% will give you about 45 miles range (and you need to be a careful driver to get the EPA range).

So - The range will decrease on both cars, but for the leaf, the range will decrease and cycling will increase in an accelerating fashion.

[WorldMaker]

I definitely understand there is a snowball effect in place, but battery research (and as one example, GM's field testing) makes it pretty clear that degeneration occurs much faster when the Lithium-based batteries are used out of operating temperatures, and that appears to be reflected in Leaf used sales (areas prone to more extreme temperature ranges have worse used Leafs).

It's not entirely a fair apples-to-apples comparison, but GM's Volt has generally worse range as comparable Leafs at each early generation, and Volts are showing much less battery degradation when compared. (Certainly you may argue that the range extender of the Volt will bring down cycle counts, but even just comparing electric miles to electric miles the Volt is still outperforming the Leaf on battery degradation.)

As for the 20%/80& thing, that is something that for instance GM's tech actively manages and just bases its outputs as if the ~80% was "full" to avoid consumer confusion. The issue there is not that charge percentage matters, according to battery industry standards, but that individual cells have a "directionality" that should be respected and a discharging cell never used to charge until it has 100% discharged and vice versa. With regenerative breaking it is useful to have cells always available "in the charging direction". It is interesting that GM and Tesla took different approaches in marketing that to car users.

[m463]

I read the worst degradation was at high temperature combined with high state of charge.

But yeah, don't buy a leaf from dubai or phoenix:

http://www.electricvehiclewiki.com/wiki/battery-capacity-los...

Looking at the volt, it seems to battery thermal management plus it only uses 65% of the battery capacity (similar to the 20%..80% tesla recommendation). I guess they can manage the battery capacity conservatively when there's a gas motor available.

[vvanders]

> Leafs usually charge to 100% unless you poke around and find the 80% setting.

Uf. Unless there's internal limiting where 100%=90% that's not a happy thing to do to a pack.