EV Batteries Are Defying Expectations After Miles

https://www.wsj.com/business/autos/ev-batteries-are-defying-expectations-after-hundreds-of-thousands-of-miles-8579de13

by apparent • 18 days ago

76 93 18 days ago

Isn't this old news? I remember reading about 7yo teslas used exclusively in cold climates (Norway, Finland, etc) and they found the same thing: batteries held on much better than even the manufacturer expected. And those were often 1st gen cars, which you could expect to have teething issues.

It was at the time one of the main reasons the 2nd hand markets in those countries were pretty healthy and saw a lot of movement of used cars.

radicalbyte• 18 days ago

Some of the early models - either the Chevvy or Nissan Leaf - had battery packs which would degrade very quickly. This was causes by the charging system which seemed designed to destroy them.

The expectation in the EV fan world was that modern (> 2019) battery packs were very likely to retain 80% of their charge for well over the time anyone expected with the drop to 80% itself taking most of the car's expected lifetime. This was because the standard extrapolations ignored improvements in charging algorithms and that real-world usages were expected to be better for the battery than the models.

Another prediction we made is that range under cold (or very hot) weather would be significantly reduced and that seems to be the case too.

cgyvbunji4• 18 days ago

They still die by calendar age based degradation. High miles low years isn't interesting. We know that works well. They don't like talking about the calendar age degradation. Every article like this leaves that part out. It's annoying. Many articles have been written like this. Many more will be written yet. I guess there are still people out there who don't know that EVs are ideal for drivers who accumulate high miles per year. Personally I don't think batteries are going to get interesting until solid state batteries. The problem is the electrolyte.

JumpCrisscross3• 18 days ago

They still die by calendar age based degradation

Source?

y1n0• 18 days ago

Not OP, but this talks about it: https://www.sciencedirect.com/science/article/pii/S2352152X2...

stavros5• 18 days ago

Lithium batteries age even just sitting on the shelf. I fly RC planes and we store our batteries at 3.8V to lengthen their life, but they still deteriorate even when not used. Like anything else, I guess.

small_model3• 18 days ago

False

"A 2015 Model S with over 265,000 miles on the original battery (85% capacity remaining)"

foxglacier3• 18 days ago

That's 25000 miles per year, which is high. So the opposite of false.

InsideOutSanta• 18 days ago

My EV is also over ten years old and has no noticeable battery degradation. I'm sure there is some degradation that could be measured, but in daily driving, I have the same range I did the day I bought the car.

bulbar• 18 days ago

Do you have more information regarding age based degradation? I haven't looked too deeply into the topic and I am not sure if the argument had been about pure age based degradation or about "after X years because a person will have driven Y kilometers since then".

borski• 18 days ago

This is just untrue.

XRG• 18 days ago

It is not necessarily untrue (source: am currently involved in battery R&D). However, the degree to which it is true will vary strongly based on the particular choice of chemistry, what sort of additives/agents are used (e.g. scavengers/getters), cell/pack engineering choices (protection against ingress of outside atmosphere and such), and so on and so forth.

zipy124• 18 days ago

If this is true it's interesting, as ICE cars typically prefer to be driven continuously at operating temperatures, rather than cold. This is why a high-mileage low-year car can actually have an engine in much better condition than low-mileage high year cars.

PaulKeeble• 18 days ago

No manufacturer is testing the batteries life by just charging and discharging them daily for a decade before releasing them. Instead they are using artificial acceleration techniques like getting the battery hot while charging/discharging continuously to simulate a longer lifetime. They can't realistically do anything else to estimate it. But it turns out heat is the big enemy for li-ion batteries and if you can keep them on the cooler side of their range they will last a lot longer.

memoriyato33• 18 days ago

we have EVs for almost 15 years now, one would imagine some real world data on battery life was collected already, even if not widely shared

decimalenough• 18 days ago

Battery chemistries have changed and technology has improved a lot in that time frame. Those 15 year old Nissan Leafs have terrible battery degradation, because they're not liquid cooled (hot = bad) and used batteries that degrade fast (LMO, which autocorrect thinks should be spelled LMAO). Manufacturers learned their lesson and every EV built in the last 5 years is far better on both counts.

ralferoo3• 18 days ago

There was and publicly available, although the mainstream press mostly chose to ignore it.

My VW hybrid is just over 10 years. The advertising claimed 28 miles on a charge, but the reality was about 18 maximum, with stop-start somewhat less. After a couple of months when it had calibrated, it settled displaying 21 miles for a full charge. 10 years on, and it still reads 21 miles on a full charge, but the reading is less useful in use. It's common for it to drop from 21 to 15 miles after a mile, but to stay on 1 mile remaining for around 4 miles travelled. But essentially, I don't consider the range to have deteriorated too significantly, it still feels around the same ballpark.

A lot of the original thinking about batteries comes from the Nissan Leaf, introduced in 2009, when they guessed that batteries would probably need replacing after 10 years. However, from the cars that were written off from accidents, they discovered much less battery wear than predicted, and around the time I bought my car, they were suggesting batteries would be around 80% after 10 years and most manufacturers started using that figure. I'm not sure what current estimates are, but I wouldn't be surprised if it was closer to 90% after 10 years.

It's common knowledge amongst owners that range is significantly reduced in cold weather - I'd guess from my use, maybe 20% less range on a cold winter day compared to summer.

And as to why car batteries last so much longer than e.g. phone batteries, I think it's mostly because their charging limits are much more pessimistic. Typically a car charger won't ever charge beyond 90% capacity or discharge below 10%, and this is built into its estimated range (so 0 miles remaining is 10% charge).

rsync2• 17 days ago

“They can't realistically do anything else to estimate it …”

Of course they can.

How do you think they get the MTBF for hard drives?

What they do is deploy thousands of them and wait for the first one to fail. Then they wait for the second and third ones to fail… And then they can construct a statistical abstraction for the entire population based on the very first degradations … and that doesn’t take long at all.

Tadpole91812• 17 days ago

If they want to avoid confounding variables to real world use, this could take years. Nobody wants to wait years after an innovation to sell their product, so they develop ways to speed up the testing and get a number.

A machine that presses a keyboard switch 500 times a second for several days straight is obviously not indicative of someone actually using the keyboard. But it'll get the "absolutely beat the snot out of it" number, which is usually good enough for marketing.

whatever1• 18 days ago

Wasn’t the same concern with the Toyota Prius when it was first released? Only for all the doubters to be proven wrong by the taxi drivers who kept beating Priuses for decades.

In any case battery failure seems rare but it still is catastrophic and nobody can afford replacement. Hence companies should just provide some sort of warranty / insurance product for the few unlucky folks. Seems like an ideal candidate.

foreigner• 18 days ago

They do.

ZeroGravitas• 18 days ago

Generally enforced by regulation, particularly tied to any government grant program to encourage EV adoption.

Exoristos• 18 days ago

Those old taxi Priuses have had their batteries replaced.

duskwuff• 18 days ago

They were also using NiMH batteries - a completely different chemistry from modern lithium batteries.

Taniwha2• 18 days ago

The original Prius batteries can easily have individual cells replaced (mine is 20 years old, we've replaced 2 cells) - of course Toyota want to sell you an entire battery, the wrecker will sell you a whole bunch of spares

(do this with care, an entire pack is hundreds of volts)

raychis• 18 days ago

EV batteries may be lasting far longer than most buyers expected but are consumers really going to trust the data over the headlines? There has been such a propaganda attack on EVs that it will take a long time to overcome that.

inglor_cz• 18 days ago

In late 2022, I moved into a new semi-detached house in a small project of 33 such houses total. Back then, there was precisely 1 EV here, parked openly.

This has grown to 6 in the meantime. It seems that the segment was growing even before Hormuz, propaganda or no.

beloch2• 18 days ago

If batteries are actually lasting, then it's easy to counter the propaganda. Manufacturers simply need to make sure batteries are replaceable and offer guarantees that they'll be replaced on the manufacturer's dime if they degrade.

VBprogrammer2• 18 days ago

That's easy to say when you aren't the one considering adding a huge liability to the companies bottom line.

There are also some elements of EV ownership where they require some TLC, like not overcharging them when doing mostly local journeys, not using rapid charging more than necessary etc. If manufacturers were carrying the can it would be easy to let these things go out of the window.

jwr• 18 days ago

The black PR has been very effective. I own an EV and the first question I always get from non-EV people when they find out is "…but what about the range, isn't that a problem?", while the second one is invariably "but what about the battery, I heard it only lasts a year or two and it's so expensive to replace!".

The myths are now strong and it will indeed take a long time to dispel them.

memoriyato33• 18 days ago

the propaganda works because we are all familiar with the smartphone battery degradation after 2 years, so it seems logical that same thing will happen with car batteries

oliwarner2• 18 days ago

I mean, we have an EV and you do have to think about range if you're going over 100mi away and time is tight (eg you have young children, appointments, etc)

When I can throw 100mi into my car in 5 minutes without having to do backflips to get the charger to start, or drive out of my way to specific chargers, and not pay 20 times the market electricity rate... Then people will stop worrying about it.

I do think we'll get there with new EVs (800V platforms look amazing), but it's not going to be retroactive. There are lots of EVs in used circulation where range will be a conscious consideration for another decade or two.

The early generation Nissan Leafs (no battery cooling) did most of the work to tar EVs longevity. It's not propaganda. They were shit.

rolfus2• 18 days ago

We had much of the same skepticism and anti-EV propaganda here in Norway a decade ago, when EV's started becoming popular. The usual claims was that the batteries would have to be replaced every five years, the cars would stop working in the winters, the batteries are fire hazards, the power grid won't support everyone buying EV's, etc.. All of which turned out to not be true.

Today the market share for EV's is 98% and they account for the majority of the total number of cars on the road! The people who bough 1st. generation EV's as a number two car a decade ago chose EV's as their main car before long. My own vehicles are 7 and 12 years old and holding up well, despite the 12 year old having inferior battery chemistry compared to modern cars.

Change isn't always easy or smooth, but this one is inevitable.

brikym2• 18 days ago

98% of NEW EVs. But the total market share of the fleet is about 1/3. Impressive. If EV share is 90% in a decade I wonder if Norway will see fuel stations being torn down.

Slothrop99• 18 days ago

I'll just caution that new things are often over-built to some degree. Then "engineering" is often how much margin they can squeeze-out while still hitting their warrantee targets.

General Motors built an ignition switch for decades which worked mostly just fine. Then they built one so crappy that they killed a bunch of people. Only to save 25 cents or whatever.

EVs depend heavily on 'early adopter evangelism'. I wouldn't read too much into this.

Theodores• 18 days ago

Although I have had rechargeable batteries in gadgets for decades, I would not like to have an EV parked in a garage beneath my bedroom, juicing up with many kilowatts, every night.

No amount of fire exits would help, I mean, what about my stuff?!?

No amount of insurance would cover personal belongings that could get lost, so that means stress from the stupid EV.

The technology might be generally proven (the EV could be a Toyota Prius variant) but the current iteration could be another Note 7, there is no knowing for sure.

I assure you it is not propaganda or TikTok that makes me wary of EV batteries, or any grudge, it is just that I have a different set of circumstances to the guy with a separate garage for housing an EV a safe distance away.

It took an extra decade for hospitals to allow mobile phones on their premises, they just had a different risk assessment. It wasn't propaganda that made them enforce such a ban.

Hence, although it is tempting to blame 'enemy propaganda', there is a whole spectrum of risk assessment, based on different people and different circumstances, so it will take a while, with battery chemistry essentially static for a decade before some get won over.

d12bb• 17 days ago

I hope you do not have an ice vehicle parked in your house currently, as these tend to burn much more often…

thebruce87m• 17 days ago

You are aware that there are multiple different chemistries, right? Go look at people drilling into LFP batteries on YouTube.

ICE cars are not immune to fires either - there are lots of recalls due to faults in the 12V systems causing fires even when parked.

Lio2• 17 days ago

No one throws Duracell during riots for a reason. Where as a small bottle, half filled with petrol, and a lit rag makes a pretty good anti-tank weapon.

A car with a tank full of gas is basically a big bomb.

I'd rather sleep over the electric car.

apparent5• 17 days ago

When early EVs hit the market, buyers’ concerns were well-founded. Roughly one in 12 EVs built from 2011 to 2016 have had to have battery replacements. But new data shows that more modern EVs are doing better so far. Among EVs built from 2022 on, 0.3% have had battery replacements, according to a 2025 study from Recurrent.

This is kind of a dumb comparison. It would be more useful to know how many vehicles had to have replacements within X years of being put in service. Obviously newer vehicles are much less likely to have needed a replacement at this point in time.

apparent5• 17 days ago

EV batteries aren’t without their challenges, though. A battery that is frequently fast-charged with high power loses its range, on average, at twice the rate of a battery charged at a lower power, according to telematics company Geotab.

I wish my car could charge at different rates depending on whether I'm going to need to use it again soon. If not, it could trickle charge and be full enough by the next morning.

beAbU• 17 days ago

Does you EV not have a charge rate setting for AC charging?

Or do you want such a feature when DC charging?

apparent5• 17 days ago

I charge over AC at home but just wish that I could specify the rate by telling the car/charger when I'm next going to need the car.

EV Batteries Are Defying Expectations After Miles

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