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Researchers went through data for 30 million vehicles, and found BEVs have rapidly improved their reliability and longevity with Tesla being the top-rated brand

Technology / analysis
Researchers went through data for 30 million vehicles, and found BEVs have rapidly improved their reliability and longevity with Tesla being the top-rated brand
Tesla Model 3
Tesla Model 3

New research is out that points to battery electric vehicles now having lifespans comparable to diesel and petrol cars, even under intensive use. A group of researchers trawled through a large data set from Britain's Ministry of Transport (MoT), with numbers from 2005 to 2022. Almost 30 million vehicles are recorded in the data.

The researchers found that while early BEVs were not as reliable as internal combustion engine (ICE) cars, technological advances have seen them make rapid gains; they are now close to petrol vehicles for reliability, and have a longer lifespan of 18.4 years versus 16.8 for diesels.

Furthermore, the lifetime mileage of BEVs is higher than for petrol vehicles.

Tesla is the top-rated BEV in the research. It is the second most significant EV maker in the UK sample data, with Nissan being the largest.

Electric motors having fewer moving parts subject to wear and tear compared to ICEs, improved battery technology (Tesla claims theirs will outlast the life of the vehicle), are some factors behind BEVs' reliability. 

All in all, the data shows BEVs are improving significantly, by a rate of 12 per cent per year, in terms of reliability and longevity.

Caveats such as the data being based on British conditions, the local car market there, and MoT testing, apply. It might not be directly translatable to other markets in the world with different conditions. BEVs are also represented in smaller numbers than diesel and petrol cars.

Here are some numbers collected by the researchers, in a simplified table using the 18-month preferred buffer time for missed MoT tests.

  Median lifetime (years) Median life mileage (kilometres) Number of observations
All vehicles
Average 17.8 221,392 29,858,458
Average by powertrain
BEV 18.4 199,865 41,640
Diesel 16.8 257,132 14,685,673
Petrol 18.7 186,744 15,131,145
Average of top five makes by powertrain
Fully battery electric vehicles
TESLA 20.3 328,616 7,810
HYUNDAI 15.6 223,033 192
NISSAN 18.8 196,344 20,449
KIA 18.5 187,520 438
MERCEDES 16.1 146,311 413
Diesel
SKODA 17.7 292,626 316,592
VOLVO 18.6 290,159 371,857
LAND ROVER 20.4 283,589 653,027
VOLKSWAGEN 17.6 282,654 1,572,090
HONDA 18.2 282,231 238,388
Petrol
AUDI 20.9 230,685 493,401
VOLVO 20.5 229,022 70,294
LAND ROVER 18.7 217,052 25,756
LEXUS 18.4 214,835 33,338
SAAB 17.6 213,987 38,591

(CC-BY-4.0; Attribution:Viet Nguyen-Tien, Chengyu Zhang, Eric Strobl and Robert J. R. Elliott).

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47 Comments

 

To follow up: how many petrol/diesel were fixed after failed MOT, vs BEVs?

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Could not see repair data after failed MOT in the paper.

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They will only get better too. Would you expect your fridge or washing machine to be as reliable with a petrol engine? 

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Certainly noisier....

Not aware of many that run off a battery tho?

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Probably a bad example, whiteware in general is now rubbish you will be lucky to get 10 years out of it, fridges used to last forever. A car that's well looked after will outlast a modern fridge or washing machine. This is the only reason EV's have better stats, they don't need the engine maintenance, if you look after the engine it will outlast the EV. People will be chopping in the EV's due to changing technology, 10 year old EV's will be on the scrap heap or worthless anyway.
 

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I own a 14 year old leaf. Old battery chemistry no thermal management, its range is limited 80 km's at highway speeds. But it still charges fine despite over 100'000 km of cheap travel and pollution free commuting.

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In before the usual bores come in with outdated talking points on range and quality. Prices are actually lower now in many cases than they were before the Labour subsidies ended, and range is always increasing.

My partner's Model Y is the best car i've driven at the price point in terms of ride and performance. I can get to Taupo, so range not a concern.

I'm not a greenie so any environmental benefits are a bonus.

If the reason you own a petrol car is because you like engine noise, i get that... but it's not a real argument against BEV.

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Those numbers will also improve as the power density of packs improves and the pack weights come down. In five - ten years time we could be seeing EVs 100kg - 200kg lighter than they are now. 

That's a lot less tyre wear, suspension wear, loads on key components, less energy going through shock absorbers etc. 

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Interesting how they can have 7810 observations for 'Tesla' and claim a median lifetime of 20.3 years given the first Tesla was only released in 2008, 17 years ago? 

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"To model the longevity of a vehicle, we use survival analysis, a statistical technique that deals with the expected duration of time until an event occurs."

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Interesting, from what I understand LI batteries capacity falls off a cliff after a certain number of cycles rather than a gradual decline. Doesn't seem conducive to a 'survival analysis'.

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They do have liquid cooling in a lot of the new cars which might help mitigate some degradation, but I do agree that they haven't really been around long enough for us to have a clear idea of how they will go in 20+ years.

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New research from Stanford suggests batteries last quite a bit longer than previously thought.

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I imagine the recycling infrastructure for used batteries will improve as well as more vehicles transition to electric. It's not like the expensive materials in batteries disappear overtime there must be a lot of value even in a flogged battery.

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The initial degredation is fastest, it then slows down and flattens out at next to no further degradation. Typically around the 80-85% capacity mark. Heat is the worst factor for degrading a traction battery, so absurd ly hot environments combined with predominantly fast charging (which causes more heat stress) and deeep cycling are the things to watch out for.
Trickle charge at home off the AC opn a regular basis and you can minimise those factors.

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Couldn’t agree more, I thought about a wall charger, but even if I’m not fully charged over night from sub 20% I’ve rarely had a day where I’ve needed a top up. 

Mobile charger is fine and charge to 75% is more than enough for daily, I might use 10/20% per day.

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Same with humans. 

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I do have the same concern with the projected life of deep cycle lithium batteries. they predict a 20 year life span after a couple of years of testing. 

After working with lead acid batteries for 25 years , i see so many variables , i am cautious to give battery life estimates, 

Cisro(?) in Australia do the most exhaustive battery tests, with some surprising results . they did lithium powerwall tests , can't remeber how Tesla fared , but they wernt top.  

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*CSIRO

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  1. Thanks, and it wasn't them doing the powerwall test, it was itp It appears to have been removed from their website, I have it on pdf.
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And the mighty Leaf, flagship if the most sold BEV brand in the UK, is only 15 years old.

I thought the numbers were bunk, myself, and wondered who paid for them.

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Yep, so most of this data is coming (in the case of EVs) from the very early models, those which were essentially on the learning curves re design and manufacture... back when battery management and thermal management were afterthoughts.

The later models are yet to age significantly, at which time they will pull the stats even longer for EVs.

It seems undeniable, once batteries are considered likely to outlast the cars themselves, there's no savage heat to disperse, no thrashing moving parts to keep cool and lubricated, less noise, vibration and thermal stresses to loosen things up. EVs are great.

As for the tired argument of having to line up to get a fast charge... the only time I need a fast charge is if I've done 400km in a single day and have plans to go even further within the next day. Otherwise I just hook up to a 10 amp charge at home and trickle charge. I won't need a full charge the next day unless further large miles are planned, so the trickle charge from a wall socket will suffice in almost every occasion, so sourcing a fast charge is actually a rare necessity.

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Second question:

How many BEVs actually survive long enough to fail the MOT tests?

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What do you think might be happening to them to take them off the road permanently?
The hype about them bursting into flames is mostly just hype. All cars burn. EVs fires are just more newsworthy as they're more novel in the sense that they're harder to extinguish, can re-ingite, and can even burn when submerged in the sea. But temper that against the stats that more combustion vehicles catch fire than EVs do, and with an EV it's typically due to the battery pack suffering a significant impact. WIth a combustion vehicle it's more likely to be leaky gaskets / hoses. There's a lot of potential leak points between the filler cap and the combustion cylinders.

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To answer: like all vehicles they become uneconomical to repair, and off to the chop shop.

The floor value of a BEV where this happens is considerably higher than an ICE (but probably lower then hybrids).

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With new battery chemistry like LFP and Sodium batteries beginning to be phased in the fire risk may go down quite a lot.

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I think most commentators on Bevs have overlooked mentioning the annual service cost (after having the usual initial 3 or so years free servicing when bought new).  These costs are not insignificant according to some website the name of which eludes me.

 

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Tesla 'service' is next to nil. They recommend toping up washer fluid, checking tyre pressures, tyre rotation, wiper blades.
2.5 years driving mine, with zero need for any interventions. Not even the washer fluid.
They do have a reputation for some suspension joints not lasting well. I'm yet to encounter that, and frankly, in the whole scheme of things, I don't give a damn about it. It's a great car.

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Yes I was wondering what the servicing issue is. Polestar is, I believe, free for the first five years, or up to 100,000 km. The intervals are every 30,000 km or two years. Hardly onerous.

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I hire cars a lot and always go for an EV if possible. Cheaper to run, quieter, smoother, more linear power and faster in most applications. The new Model Y looks awesome, that and a new Amarok/Ranger would cover 99% of my needs.

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Anecdote: friend with a four year old Model 3, done about 100k needed major suspension fix. Could happen with any new car design tho

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To be fair, that doesn't come under "annual service" or even servicing in general.

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20.4  years + 283,589 km for Land Rovers? seems dodgy as they come bottom in reliability surveys, best off road car in the world; always off the road....

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Fully battery electric vehicles

TESLA20.3328,6167,810

HYUNDAI15.6223,033192

NISSAN18.8196,34420,449

KIA18.5187,520438

MERCEDES16.1146,311413

 

I cannot help but notice none of those EVs are Chinese brand, which is the biggest EV producers. 

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If I understand it right, Chinese EV vendors are new to the UK market, and didn't really feature until 2019-2020.

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I'm Tina from Turners, we love buying cars, (just not electric ones)

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yeah not buying this.

They expect me to believe that an Audi, Land rover and Saab have a longer life than a Kia, Hyundai and Nissan. Well I'm not a spring chicken anymore so I know that's not true.

But that what happens when you use models instead of actual data, you can make the model do anything you want. That's also why the polar ice caps that should have disappeared many times over during my life time are still here, because of nutty models made by researchers.

Anyway, anyone who has used anything battery related knows that batteries work well for the life they are designed for and then loose their capacity very quickly afterwards. Many variables in that including storage, recharging methods and times, discharging etc.

One an EV the weak point in terms of major failure would be the battery, on a combustion engine car it is the tra mission, followed by the engine. A quick google check tells me that it's still cheaper overall to replace a tra mission an engine in a car than a EV battery in an EV car in most cases. I haven't done the math, but I'm going to guess that most car engines will last longer than an ev battery all things being equal. Because a combustion engine in most cases will continue to work until there is a catrofricfalire and a lot of the time fuel consumption will remain relatively consistent. Where as an EV battery will degrade over time and that is more subjective. It's an EV battery no longer worth it for you when it can only hold 75% of it capacity? 65%? How long did it take to degrade to that level? 7 years? 10 years?

Another calculation to consider is this. If a car cost you $20,000 to buy but after 10 years the motor fails and the cost to replace is $10,000. You're more likely to take it to the wreckers and buy a new one because the price to fix is 50% of the vehicle. If you have an EV and it cost you $80,000 and after 10 years the battery capacity is now at 70% and you decide to replace the battery, it costs you $20,000, but that is only 25% of the cost of the vehicle and replacement cost is still $60-70,000. So you decide to get a new battery. Do the EV really last longer? No. Just that in this case you decided to repair it rather than replace it. 

And yes while servicing costs are cheaper because there is no oil, you go through brakes and tyres faster as the ev vehicles weights significantly more. I just paid $1300 for new tyres and wheel alignment, and that was saving about 30% because of Black Friday. I've seen figures from 20% to as high as 50% depending on the source. So you can see how the difference in maintenance seems to me to be about equal with how expensive tyres are now.

It's a simplistic study that could be completely wrong based on modelling. 

I guess a few decades will tell us the answer, but I suspect by then no one will be allowed to drive anyway.

I heard more than one CEO of car giants and technocrats at the World Economic forum say that the concept of car ownership in the future is dead and too reach net zero we have to give up all cars and instead rely on self driving ride share taxis. 

But hey, I'm sure they'll still be Gran Turismo on the Playstation to play. 

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Ooh, you hit on a maintenance point that I had overlooked, but it's not what you think it is...

EV's, thanks to their regenerative braking (using the motor to put energy back into the battery and creating a braking force at the same time... like a generator) don't need to use the brakes as much, to the degree where the brake rotors lacking a regular scrubbing from brake pad pressure begin to rust up. This can eventually create the need to have the rotors machined to shine them up again to a nice smooth gripping surface.

I drive pretty gently. My car stays in 'Chill' mode. It is very rare that I have to touch the brakes to come to a standstill. Usually I merely apply the brakes as a saftey measure once already stationary, so the rotors get zero scrubbing. So the brake pads will likely last the life of the car (unless driven with a hard braking style). The rotors however might be a bigger job.

I thought I could somewhat counter this by briefly applying brake pedal pressure while still holding the accelerator down to maitain speed, but the car interprets this as a foot misplaced over both pedals and alerted me that it had reduced motor power due to both pedals being in use simultaneously, allowing the car to slow. I might just have to drive it harder into intersections in order to force the use of the brakes.

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thanks for your detailed feedback on the EV brakes.

Really appreciate it :)

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Yeah, we will have to give up cars. They’ll stick with private jets thanks.

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They need them to get to Davos don't cha know!!!!

 

 

 

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Until i see a battery vehicle that can last 50years, tow a boat, be fixed in any town for a reasonable price and the skills to fix them is more ubiquitous, and you can charge your EV in 5min, id have to disagree with the title. Not hating, just saying diesel has history on its side currently

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Classic comment, ignore the statistics presented in the article which state the median lifespan of a diesel powertrain is less than petrol or electric (which is still a relatively new technology) and make up your own mind. Although admittedly a diesel does more kms in the data.

I also suspect finding parts to fix your loud, clunky and very slow 50 year old 1975 diesel land rover (with history on its side), in any small town might, not be as simple as you allude to.

And if you a buying a new car with the intention of running it for 50 years, I expect you might find that a challenge to, as the closing of petrol stations start to accelerate.

History was also on the side of the horse and cart for a long time, until it was not.

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Classic comment, ignore the statistics presented in the article which state the median lifespan of a diesel powertrain is less than petrol or electric (which is still a relatively new technology) and make up your own mind. Although admittedly a diesel does more kms in the data

Just because one has a preference doesn't make them averse to statistics. We all know fruit and veg are good for us but do we eat nothin but them 65 days per year and seem adverse to the information if choosing otherwise?

History shows that horse and cart was prevalent until a more mass manufactured automobile came to be with vast greater efficiencies given the source of energy was easily accessed oil when there was plenty that was land-based. I've not yet got faith in the electricity sector to be able to supply mass adoption of vehicles putting additional demand on it, but likely you'd pay back a hybrid in savings before the cost got too excessive to say otherwise in comparison to oil.

 

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Not light motor vehicles (yet), but in 10 years? https://amogy.co/

The technology is evolving so fast that buying a vehicle is becoming like buying a PC, back in the day: the latest and greatest comes with a pamphlet in the box that tells you next month's model is going to be better in every way.

The consumer's question becomes when to step on to the technology merry go round and buy your own piece of obsolescence.

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