I have been considering buying 2016 Nissan Leaf with about 67K miles on it. But the more I read, the less I liked. So I’m punting. Briefly, here’s why.
Mainly, it’s that once the battery loses enough capacity, it doesn’t age gracefully. Instead, it can begin to fail sporadically, typically under under heavy load. As in, say, not being able to keep up with traffic on the interstate, for any length of time. Not being able to accelerate at full power during a highway merge. Worse, you won’t know you’ve exceeded its limit until you have exceeded its limit. The car becomes sporadically unreliable.
Separately, a weak-enough battery will cause the car to turn off regenerative braking. Which then accelerates wear and tear on the traditional hydraulic brakes.
How much battery loss is enough to do that? Tough to say.
This car had only lost three battery bars, out of twelve. Doesn’t sound too bad. Then I found the exact definition of the what the “battery bars” mean, at this website. It’s non-linear. By the time you’re down to nine bars, the battery may have lost one-third of its capacity. Lose another bar — down to eight, total — and Nissan considers the battery to have failed, and will replace it if the battery is still under warranty.
So I wasn’t just buying a used Leaf. I was buying a used leaf with a battery on the cusp of being degraded enough that Nissan considers the battery to have failed.
This is materially different, I think, from buying a used gas car. It’s just a different mode of failure, entirely, from a typical junker of a gas car.
Gas beaters, in my experience, tend to be yes/no vehicles. Yes, it’ll drive, or no, it’s not going anywhere.
The worst beater I ever drove was a 1974 Chevrolet Vega. Truly dreadful car, burned oil like there was no tomorrow. (My dad used to joke, when you take that to the gas station, you ask the attendant to check the gas and fill the oil.) But that car remained capable of extended highway driving right up to the end of its life.
But this car? I get the impression that this car will continue to be drive-able, somewhat, every day, for a considerable time yet. It’s just that, in the meantime, it gets less and less like a fully-capable auto, and more and more like a neighborhood electric vehicle. Fine for low-speed suburban roads. A gamble on the interstate.
Thrown in range loss in cold weather, and lack of a battery management system to keep it cool in warm weather, and it has all the earmarks of being a temperamental vehicle. I’ve driven gas-powered beaters like that — cars that wouldn’t start in the rain, cars that lost power at low temperatures — and I’m just too old (and no longer poor enough) to go back to that. My experience is that an unreliable car is worse than no car at all.
It’s not as if these problems are guaranteed to occur. It’s that if you buy a Leaf with this much battery loss, miles, and age, you are at risk for them. Whether or not they crop up seems to depend in large part on how uniformly the individual battery modules have aged. From what I can read, the car defends the weakest module, so to speak, so a few weak modules will limit the ability to be discharged (or charged) at high rates of power.
And, from what I read, some owners just get used to babying their cars. They learn the cars limits, and they live within them. Not a bad strategy for a car you already own, but not ideal when seeking out a used car. I don’t want to buy a car with a sword hanging over my head.
In short, some Leaf batteries age more gracefully than others. If you have the bad luck to draw a pack with uneven aging among the modules, you’re going to run into these problems sooner, rather than later. In theory, I could either buy the software and equipment (cheaply) to look for that, or take it to a shop that could test the battery. But I don’t have enough experience with these to trust my judgment, were I to do that.
If I were looking for a three-season, suburban-streets vehicle, this would be a low-risk purchase. And a lot of old Leafs get used just like that, and odds are that this particular car would function adequately in that role for years to come. But as a car that has to work as a fully-functional interstate-capable vehicle in any season, I think this car, with that much loss of battery capacity, is a risk.
I guess the last straw was when I discovered that this particular age of car is still subject to having the battery overheat. I thought Nissan wised up an put in some sort of cooling system, at some point, like every other EV manufacturer. But if so, that’s later than 2016. So, much like the clunkers of old, some people have to stop by the side of the road to let their car (battery) cool down, or limp home in “turtle mode” under reduced power.
So it’s not exactly back to square one. I know a lot more now than I did. Really, I aimed too low, hoping to buy one of these for under $10K. I’m going to have to aim higher if I want to buy some years of owning a trouble-free and fully-functional EV.
