How useful is the battery warranty, really?

One manufacturer of a car model that's up to 14 years old at this stage is enough to change your mind? Maybe I should mention the Ford Focus econoboost or the Mazda skyactiv and put you off petrol and diesel cars respectively for good also?

Mention whatever you like. I not taking a gamble on it anyway. Everyone else can do whatever they want.

I'm not.

The annoying part is that this should be very easy to spot as the manufacturer. They likely have all the battery history from initial testing all the way to customer handover

In addition, it should be simple enough for the car to log the battery cell voltages. It's already monitoring them, writing to a log file which can be exported is simple enough

So a manufacturer could very easily look up all the cells in a problem car and possibly see that one of the cells was right on the control limits during assembly and then the voltage rapidly dropped in the first few months indicating a bad cell

Had a cell or some kind of battery part fail in my Nissan Leaf 62kWh only a month into my ownership.

Nissan had it for a month and paid for a Toyota RAV4 for me to run about in. Thought it was odd they didn't arrange another Leaf or other Nissan but hey.

All sorted anyways. Seems rag order not to give that lady the same treatment as her battery is still in warranty.

Obviously the marketing and warranty departments don’t talk to each other.

We're just going to ignore all the Leafs, Zoe's, Tesla's and other EVs that are older than their warranty

Completely data free discussion here. And not likely to be resolved without any.

You claimed they haven't been tested, which is obviously untrue. There's been EVs around since 2010 and it doesn't take much googling to find out about Tesla warranties or Renault battery leasing for example.

Not sure "My warranty doesn't include what I thought it did" is really something that somehow applies only to EVs and their batteries. We've been using lithium based batteries for decades and the methods of increasing longevity have been well known for at least half that time.

I appreciate that faults are in a different category from degradation, but we're now at a point where these things can be repaired without going back to the manufacturer and quite a bit cheaper. There are at least three specialists in the country who can do this.

The Nissan Leaf was the first mass market EV to be produced and unsurprisingly also the one with the most battery degradation problems. But there are always at least 100 of these on sale on DD with expired battery warranties. So it's not inevitable that the end of the warranty is the end of the car.

That depends on whether the cost of the repair exceeds the value of the car. And as I said, there are now independent specialists replacing battery modules at much lower costs than manufacturers and dealers. There was a YT video posted here a while ago of one such independent replacing a battery module and it's not as big or complex a job as replacing an engine or gearbox. At least not to my mind. The only thing stopping me from doing it (and I'm no expert) would be the lack of a vehicle lift.

The story won’t be good for trying to increase EV sales right now that’s for sure.

I’ve been the owner of many an ICE car that was 8 years and older - I reckon there’s a massive % of the population who own a car that’s 8 years or more in age.

We know reduced milage due to battery degradation is a feature of EVs - that’s something most people will accept and with range rates increasing all the time, not too much to be worried about- but with these kind of stories, it will force down second hand prices even more, leading to high depreciation of new EVs , leading to even less people buying new EVs.

There needs to be some form of national guarantee put in place on batteries over 8 years - if failure rates are as small as were led to believe then this should be a piece of cake to implement - but with reactions from car manufacturers like Nissan, I’m not at all convinced they’re as confident as they make themselves out to be

We know reduced milage due to battery degradation is a feature of EVs - that’s something most people will accept

Do we? What do you think the average degradation of batteries is after six years?

…but with these kind of stories,

These kind of stories about one model that is well known for having a particularly bad battery chemistry that pretty much baked in degradation which only increased with the amount of fast charging the car was exposed to, is really not indicative of modern EVs. Granted that it's not helping the case if people don't actually do any research beyond listening to Liveline.

For me thats not really valid comparison. You really want EV batteries to be made in a way they can be more easily repaired if faulty from a consumer right to repair point of view.

I think in this case with the Leaf the manufacturer needs to be taken to task.

Based on what? Current models of EVs are showing very little battery degradation as understanding and development of battery chemistry increases as well as methods of charging. Charging to below 100% is now the norm with modern EVs which has seen negligible degradation of batteries when implemented. Low single figure percentages after three years is becoming the norm.

I meant the "will increase as battery increases with age" bit.

Assuming you mean health of a battery is indirectly proportional to its age, that's not the case. The main factors affecting the health of an EV battery have been determined to be charging patterns and type (AC or DC) rather than age.

Theres a randomness to degradation. With a few outliers here and there.

And tell me this then - if the so called “experts” can’t agree on how a battery will age beyond 6 years and at what rate, where does that leave the secondhand car buyer- so much for them

Somehow this thread keeps drifting back to degradation which is not what it's about. It's about what happens if my battery develops a fault during its 8 year battery warranty.

And remind me what has all of this got to do with a car manufacturer not honouring a battery guarantee?

The HV would keep my hands in my pocket😎