While it’s very likely to simply be a matter of the company looking to protect itself from potential lawsuits down the road, the Chevy Bolt EV owner’s manual section on battery degradation and range loss raises some interesting questions.
The owner’s manual (page 322) states that the battery pack capacity could degrade by as much as 40% over the 8-year warranty period. Or by as little as 10% over that same time period. It certainly sounds like this is just a matter of the company protecting itself from being sued, but also seems worth highlighting.
Here’s the full section from the owner’s manual: “Like all batteries, the amount of energy that the high voltage ‘propulsion’ battery can store will decrease with time and miles driven. Depending on use, the battery may degrade as little as 10% to as much as 40% of capacity over the warranty period. If there are questions pertaining to battery capacity, a dealer service technician could determine if the vehicle is within parameters.”
While that figure isn’t likely to relate to many (or probably even more than a few) owners, a 40% decrease would result in quite a dent to the model’s range — from 238 miles per full charge down to ~143 miles. Obviously, battery packs can always be replaced, but that would still be quite a drop, and something to think about if eventual resale is a consideration.
Autoblog notes in its coverage that “since the Bolt EV is the one that GM wants to promote to a much wider audience than the typical EV buyer — we have to wonder if this sort of range decrease will be acceptable to the masses.”
A good point. While I understand the need to cover oneself from lawsuits, the phrasing in the owner’s manual is likely to lead to some people interpreting this as a sign that the Bolt EV battery will degrade rapidly. Going by the way that Chevy Volt plug-in hybrid battery packs have held up to date, though, this is unlikely to be true.