Edit 2/11/2023: I grossly underestimate the replacement cost for a Prius Prime lithium-ion battery. Per this thread on Priuschat, the cost of new Prius Prime battery, from the dealer, is $12,595. Others suggested the dealer took some markup, as the list price from Toyota is just under $10,000. I say, potato, potahto.
In round numbers, the cost of a new replacement battery is 43% of the cost of a brand-new Prius Prime, base model, current MSRP $28,770. As a footnote, literally none were available in North America, and the battery has to be shipped directly from Japan.
I should put in the usual EV-weasel-wording: By the time the battery dies, there will be plenty of good-used batteries in junkyards, from wrecks. That did, in fact, happen with the original Prius NiMH hybrid battery. Plus, there may be much cheaper aftermarket replacements at some point. And so on. But right here, right now, what I cited are the hard numbers for battery replacement cost.
Original post follows.
Only Volvo offers any warranty on your plug-in hybrid electric range, near as I can tell.
And I think I have finally nailed down why that is.
A typical battery guarantee for a fully electric vehicle (EV) is that a car will lose no more than 25% of range in 8 years/100,000 miles.
Based on research shown below, using actual driving behavior, for a Prius-Prime-like plug-in hybrid electric vehicle (PHEV), you would expect about 5% of batteries to fail, under that 8-year, no-more-than-25% loss definition. Just from normal wear-and-tear, as-typically-driven.
So, my guess is that PHEVs don’t get those guarantees because manufacturers would end up replacing too many batteries.
All the more reason to treat your battery gently.
Background
Last week, I found out that my wife’s Prius Prime had no warranty on its electrical range. Currently, as we drive it, we get mid-30-miles on a charge. But if that drops to zero, tough. As long as the car will still run as a hybrid, they battery has not “failed” under Toyota’s 10-year/150,000 mile warranty.
So I got curious. I already have a list of all 2022 plug-in hybrid electric vehicles (PHEVs), from a just-prior post. I decided to look up the warranty information for as many manufacturers as I could find.
Here’s the results.
Volvo offers a 30% loss-of-range warranty. If you lose more than that, during the eight-year warranty period, they’ll fix it.
Near as I can tell, none of these other manufacturers offer any warranty whatsoever, on the electrical range of their PHEVs.
Toyota
Kia
Porsche
MINI
Ford
Chrysler
Mitsubishi
Jeep
Hyundai (I think)
BMW (but maybe they decide case-by-case?)
The Hyundai warranty covers EVs, PHEVs, and hybrids, and in separate places says that it definitely covers loss of range, and that it definitely does not cover loss of range. Your guess is as good as mine, but I’m guessing they cover range for EVs (as required by law) but not for PHEVs.
Originally, I could not understand why Toyota offered no PHEV range warranty. That situation has now improved. I’m now baffled why almost nobody offers a PHEV range warranty.
Unfortunately, I think that “no PHEV range warranty” is the industry norm for precisely the reason stated in the Toyota warranty documents:
I’m an economist by training, and I find it this interesting, I guess. When there’s a de-facto industry standard, there’s usually a reason for that.
And I think I understand why no-PHEV-range-warranty is the industry standard.
How many would “fail” under normal driving conditions?
I’ve been searching for an answer for this for the better part of a week. I posted my thoughts on preserving battery capacity on a chat side dedicted to the Prius (PriusChat), and with a few exceptions, got met with derision. For sure, nobody there had ever heard of a Prime or the prior version (Plug-in Prius) showing any signs of premature loss of range. Almost nobody thought that any sort of battery-protecting behavior was necessary.
I finally came across what I believe is a realistic projection of the fraction of Prius-Prime-like vehicles that would fail under the typical EV warranty of no more than 25% range loss in eight years/100,000 miles.
That’s: Comparison of Plug-In Hybrid Electric Vehicle Battery Life Across Geographies and Drive Cycles, 2012-01-0666, Published 04/16/2012, Kandler Smith, Matthew Earleywine, Eric Wood, Jeremy Neubauer and Ahmad Pesaran
National Renewable Energy Laboratory, doi:10.4271/2012-01-0666
They used actual driving data from about 800 trips taken by Texans in PHEVs. The then extrapolated that to eight years of driving behavior. Their model is not quite perfect, as the modeled vehicle only provides a 10% “buffer” at maximum allowable charge, while the Prius Prime provides 15%. On the other hand, for the key chart, they did not include (e.g.) the effects of high temperatures on battery life. (So, no parking your car in the sun in this model, so to speak).
Here’s the key graph, where the most Prius-Prime-like vehicles is the PHEV40.
Source: Cited above.
In a nutshell, only counting the wear-and-tear from normal driving and charging, they expect the average user to lose 20% of range by the end of the eighth year. And about 5% of users would experience in-the-neighborhood-of 25% range loss.
If they were to throw in the effects of variation in climate (hot climates kill batteries quicker), and variation in practices regarding storing the car fully charged (which also kills batteries quicker), I might guess that around 10% of drivers might exceed that 25% loss threshold within an eight-year warranty window.
To put that in perspective, car manufacturers as a whole spend about 2.5% of their total revenues on warranty repairs (reference). A ten percent failure rate of this part, replaced at new-battery cost shown above, would by itself account for (roughly) 4 percent of Toyota revenues from Prius Prime sales.
As far as I’m concerned, this solves the mystery of the missing warranty. (Almost) nobody offers anything like the standard EV warranty, because if they did, they’d have to replace an unacceptably large fraction of batteries under warranty. And that would lead to an unacceptably high warranty cost.
All the more reason to avoid unnecessary wear-and-tear on a PHEV battery.
