Just purchased a 2015 Tesla Model S 70D for $9k (USD). It was very worth it. It still holds about 88% of its charge after 175k miles. There are also some positive factors you didn’t mention.
There’s a lag in the market when it comes to mileage of EVs. If I bought a 175k+ petrol/gas car it would likely be on its last legs due to all of the moving parts, but with an EV it still runs about as well as it did new. But I could still use the mileage to negotiate the price down.
There is some more intrinsic value because of the battery. Degradation doesn’t matter for a lithium ion battery’s recyclability, though at the end of its life for a car it would probably be best used as some home storage capacity rather than being recycled immediately. This value is in addition to some value from being able to repurpose other parts of the car at the end of its life.
Finally, with savings on gas/petrol, I only need this car to last about 2 years give or take, depending on residual value, and it will have paid for itself in fuel savings + trade in value alone.
Depends on the make. Our family has not yet had a Toyota or Lexus that lasted much less than 250k, and a couple of other makes have been close to that.
Whilst it is true that a very rare battery defect after the warranty expires will result in a big bill, the same is true for the many thousands of people driving around in a VW group car with the great (when working) but horribly complicated DSG twin clutch gearbox. They are only warranted for 3 years and I friend was hit with a £10k replacement bill when it broke at 4 years. Manufacturers should do better with their warranties but I don’t see a great deal of difference between the two situations personally. I have just returned my Kia EV6 after 3.5 years and the range hasn’t budged (still 320miles) and it retained a further 3.5 years of warranty on the whole car.
It is, in fact, a dealbreaker. Most car buyers buy used. Replacing a suddenly failed battery is incredibly expensive once it's out of warranty.
This fact alone makes it very difficult to sell eight-year-old EVs. Few sensible people want to buy a vehicle when they could be up for more than twice its purchase price in repairs, with no way to know if and when.
And no, don't tell me about Battery Health Certificates. The certifiers aren't offering to replace your car free of charge if they got it wrong and the battery fails.
And because the battery is big, the risk of it being damaged in a minor accident is large, so repair costs are very high and very likely. Will Battery Health Certifiers replace your battery after a carpark contretemps? Didn't think so.
Yes yes, the frequency of occurrence might be low, but the cost if it happens is extreme. That makes it highly salient.
These risks drive down the price and the size of the market for older used EVs. Because the market for eight-year-old EVs is small, the market for three- to five-year-old EVs is small. Buy one, you're stuck with it.
Until manufacturers offer free no-questions-asked lifetime battery replacement, this is going to be a problem. If the frequency of battery failure is so low, they should be happy to do that.
Or they could do what they should have done in the first place: made batteries standardised and quickly swappable, so they are not included in the vehicle price.
I've had a timing belt go on a second hand car. Sudden (on the M40 in my case), low frequency of occurence incidents that are expensive compared to the cost of scrapping and replacing a car are not confined to EVs. Deterioration to the point where the car is not worth fixing is the experience of most high-mileage ICE vehicle owners sooner or later.
The damage cost in any collision would be covered by fully comp insurance. If this was a major problem then EV insurance would be substantially more expensive than ICE insurance.
Can see the argument for standardised batteries but it's not like anything much is standardised across different models of ICE vehicles.
I've had a timing belt go on a car years ago, and just this year a complete engine replacement. Wearable costs in the low $000s. Replacing a battery? No thank you.
You are correct: EV insurance is more expensive than ICE insurance. Leasing costs on EVs are also higher now, because of the much higher depreciation.
"15,000 cars — which had collectively clocked up 250 million miles" is an average of less than 17000 miles each. What is surprising is that any needed a battery change.
Good post! I do think even the fairly small degradation we’re seeing (15-20%) makes having a good initial off the lot range so important.
That there are still good brands that have cars leaving the lot with reported 180ish mile ranges is nuts. The idea they could be down to around 150 miles in a couple of years is harsh.
Really useful. Why can't the energy management system in an EV partition the batteries into those providing power from the rest to allow re-charging whilst driving?
The average age of a car on the road in the US is 12.6 years. Not the average lifespan - the average age of a car actively in use.
If you lose 2% per year, that’s up to over 25% just from chronological aging for the average age of the car, plus another 10-20% from mileage means 35-45% gone.
My family currently has a well maintained car, running well and without issues, that’s 22 years old. That would have 44% gone just from chronological aging if it was an EV. Add another 10-20% from mileage, that’s 54-64% gone.
This is actually an issue.
Most cars on the road are kept in service for a VERY long time, even if not by their original owner.
It doesn’t seem to stack like that. As I said, the model S I bought that’s about 10 years old seems to have only lost about 12% capacity and Hannah is saying capacity loss happens faster early in the car’s life
Maybe but what about the mecanical costs and all the CO2 produced in their long lifetimes? It will still be cheaper and less CO2 to keep buying used electric ones twice as often. Batteries and cars are recyclable, not the petrol that you burn.
For now EVs are like computers used to be: the rate of technological improvement is such that older cars (say 5 years old) are obsolescent. They don’t have the computing power that new models have. I’m thinking of Tesla.
I have a 6 year old Tesla Model 3. I'm not aware of any aspects of obsolescence. In fact my car has improved and had a number of features added through software updates, and I continue to receive these. The newest versions of the car (like most brands) have added technical improvements to many areas over the years but these don't make my own car worse! This is massively different to your example of outdated computers which become slower or unable to complete the tasks you bought them to do ... may car was bought for driving from A to B and it continues to that as effectively as ever.
I have a 2021 MY. I was referring to Hardware 4, which has better cameras, more memory, and a more powerful processor than our cars. I thought the form factor differences between 3 and 4 would not allow an upgrade, but I just read that anyone with FSD will get a free upgrade to 4 in the future (not now). Hardware 3 has apparently reached its limit.
Yes, newer cars have some newer tech but my point was just to clarify that this doesn't qualify an older car for the term obsolescence! In terms of FSD (Full Self Driving) features this is a very expensive option that very few Tesla owners buyers buy ... at least here in the uK.
I'd like to see a lot more car parks in the UK covered by solar panels but "Try to keep it out of direct heat if you can" is not very helpful advice for potential EV owners. That sounds like, as well as the issue of where and how you charge it at home, you really need a car port for it as well.
Thank you for this article, Hannah. You explain very clearly how calendar aging accelerates in hotter conditions. I wonder if climate extremes could create a third category: climate aging. As heat waves and sudden frosts become more common, batteries might not just age in time or cycles, but in climate.
Yes yes yes! As someone who works in clean transportation, myth busting and breaking through misconceptions is so important on the road to greater zero emission adoption. Thank you for this!
You may have read this already but on Aug 21, Mazda and Toyota announced a project to evaluate the use of old EV batteries to support the grid. Initially they will test it on Mazda's internal grid but then hope that they can be used to stabilize output from renewable energy providers.
"This will enable the verification of stable, high-quality, and efficient charging and discharging. In the future, the storage system will be used to regulate power supply and demand from renewable energy, which fluctuates depending on weather and time of day, contributing to carbon neutrality."
1. I initially installed a level 2 charger at my home, but realized I can get by with level 1 charging most of the time. Is there any difference on my battery degradation?
2. I recently got a TM3 with an LFP battery, they recommend charging to 100% regularly - thoughts?
Question: does battery degradation affect efficiency? E.g. if a battery degrades to 80% of original capacity, does it require 80% as many kWh to charge it (no loss of efficiency), or does it still require the same amount of energy to charge it (with energy somehow being lost in the charging or discharging process)?
These are good question to ask indeed! Can car with say 80% battery capacity have same performance as new one(sufficient)? Is degradation fairly linear of is it becoming catastrophic after some point? Large battery on EV degraded to, lets say 50% would still offer good city driving range for years to come unless it cannot be used(significant performance drop), or becomes fire hazard, or cannot support enough "umpf" when accelerating. These are details that matter.
There’s a podcast called Catalyst that did an episode on repurposing EV batteries for electrical grid storage. They talked about the high capacities of the second hand batteries they received, as well as the economics and challenges of EV battery repurposing. A very interesting extension of what you talk about in this article!
Just purchased a 2015 Tesla Model S 70D for $9k (USD). It was very worth it. It still holds about 88% of its charge after 175k miles. There are also some positive factors you didn’t mention.
There’s a lag in the market when it comes to mileage of EVs. If I bought a 175k+ petrol/gas car it would likely be on its last legs due to all of the moving parts, but with an EV it still runs about as well as it did new. But I could still use the mileage to negotiate the price down.
There is some more intrinsic value because of the battery. Degradation doesn’t matter for a lithium ion battery’s recyclability, though at the end of its life for a car it would probably be best used as some home storage capacity rather than being recycled immediately. This value is in addition to some value from being able to repurpose other parts of the car at the end of its life.
Finally, with savings on gas/petrol, I only need this car to last about 2 years give or take, depending on residual value, and it will have paid for itself in fuel savings + trade in value alone.
Depends on the make. Our family has not yet had a Toyota or Lexus that lasted much less than 250k, and a couple of other makes have been close to that.
Whilst it is true that a very rare battery defect after the warranty expires will result in a big bill, the same is true for the many thousands of people driving around in a VW group car with the great (when working) but horribly complicated DSG twin clutch gearbox. They are only warranted for 3 years and I friend was hit with a £10k replacement bill when it broke at 4 years. Manufacturers should do better with their warranties but I don’t see a great deal of difference between the two situations personally. I have just returned my Kia EV6 after 3.5 years and the range hasn’t budged (still 320miles) and it retained a further 3.5 years of warranty on the whole car.
It is, in fact, a dealbreaker. Most car buyers buy used. Replacing a suddenly failed battery is incredibly expensive once it's out of warranty.
This fact alone makes it very difficult to sell eight-year-old EVs. Few sensible people want to buy a vehicle when they could be up for more than twice its purchase price in repairs, with no way to know if and when.
And no, don't tell me about Battery Health Certificates. The certifiers aren't offering to replace your car free of charge if they got it wrong and the battery fails.
And because the battery is big, the risk of it being damaged in a minor accident is large, so repair costs are very high and very likely. Will Battery Health Certifiers replace your battery after a carpark contretemps? Didn't think so.
Yes yes, the frequency of occurrence might be low, but the cost if it happens is extreme. That makes it highly salient.
These risks drive down the price and the size of the market for older used EVs. Because the market for eight-year-old EVs is small, the market for three- to five-year-old EVs is small. Buy one, you're stuck with it.
Until manufacturers offer free no-questions-asked lifetime battery replacement, this is going to be a problem. If the frequency of battery failure is so low, they should be happy to do that.
Or they could do what they should have done in the first place: made batteries standardised and quickly swappable, so they are not included in the vehicle price.
I've had a timing belt go on a second hand car. Sudden (on the M40 in my case), low frequency of occurence incidents that are expensive compared to the cost of scrapping and replacing a car are not confined to EVs. Deterioration to the point where the car is not worth fixing is the experience of most high-mileage ICE vehicle owners sooner or later.
The damage cost in any collision would be covered by fully comp insurance. If this was a major problem then EV insurance would be substantially more expensive than ICE insurance.
Can see the argument for standardised batteries but it's not like anything much is standardised across different models of ICE vehicles.
I've had a timing belt go on a car years ago, and just this year a complete engine replacement. Wearable costs in the low $000s. Replacing a battery? No thank you.
You are correct: EV insurance is more expensive than ICE insurance. Leasing costs on EVs are also higher now, because of the much higher depreciation.
"15,000 cars — which had collectively clocked up 250 million miles" is an average of less than 17000 miles each. What is surprising is that any needed a battery change.
Good post! I do think even the fairly small degradation we’re seeing (15-20%) makes having a good initial off the lot range so important.
That there are still good brands that have cars leaving the lot with reported 180ish mile ranges is nuts. The idea they could be down to around 150 miles in a couple of years is harsh.
Really useful. Why can't the energy management system in an EV partition the batteries into those providing power from the rest to allow re-charging whilst driving?
The average age of a car on the road in the US is 12.6 years. Not the average lifespan - the average age of a car actively in use.
If you lose 2% per year, that’s up to over 25% just from chronological aging for the average age of the car, plus another 10-20% from mileage means 35-45% gone.
My family currently has a well maintained car, running well and without issues, that’s 22 years old. That would have 44% gone just from chronological aging if it was an EV. Add another 10-20% from mileage, that’s 54-64% gone.
This is actually an issue.
Most cars on the road are kept in service for a VERY long time, even if not by their original owner.
It doesn’t seem to stack like that. As I said, the model S I bought that’s about 10 years old seems to have only lost about 12% capacity and Hannah is saying capacity loss happens faster early in the car’s life
Maybe but what about the mecanical costs and all the CO2 produced in their long lifetimes? It will still be cheaper and less CO2 to keep buying used electric ones twice as often. Batteries and cars are recyclable, not the petrol that you burn.
You read the article?
For now EVs are like computers used to be: the rate of technological improvement is such that older cars (say 5 years old) are obsolescent. They don’t have the computing power that new models have. I’m thinking of Tesla.
I have a 6 year old Tesla Model 3. I'm not aware of any aspects of obsolescence. In fact my car has improved and had a number of features added through software updates, and I continue to receive these. The newest versions of the car (like most brands) have added technical improvements to many areas over the years but these don't make my own car worse! This is massively different to your example of outdated computers which become slower or unable to complete the tasks you bought them to do ... may car was bought for driving from A to B and it continues to that as effectively as ever.
I have a 2021 MY. I was referring to Hardware 4, which has better cameras, more memory, and a more powerful processor than our cars. I thought the form factor differences between 3 and 4 would not allow an upgrade, but I just read that anyone with FSD will get a free upgrade to 4 in the future (not now). Hardware 3 has apparently reached its limit.
Yes, newer cars have some newer tech but my point was just to clarify that this doesn't qualify an older car for the term obsolescence! In terms of FSD (Full Self Driving) features this is a very expensive option that very few Tesla owners buyers buy ... at least here in the uK.
I'd like to see a lot more car parks in the UK covered by solar panels but "Try to keep it out of direct heat if you can" is not very helpful advice for potential EV owners. That sounds like, as well as the issue of where and how you charge it at home, you really need a car port for it as well.
The keeping out of direct heat advice may be worth thinking about in Texas but not the UK!! It is simply not an issue here.
Thank you for this article, Hannah. You explain very clearly how calendar aging accelerates in hotter conditions. I wonder if climate extremes could create a third category: climate aging. As heat waves and sudden frosts become more common, batteries might not just age in time or cycles, but in climate.
Yes yes yes! As someone who works in clean transportation, myth busting and breaking through misconceptions is so important on the road to greater zero emission adoption. Thank you for this!
Hi Hannah,
You may have read this already but on Aug 21, Mazda and Toyota announced a project to evaluate the use of old EV batteries to support the grid. Initially they will test it on Mazda's internal grid but then hope that they can be used to stabilize output from renewable energy providers.
"This will enable the verification of stable, high-quality, and efficient charging and discharging. In the future, the storage system will be used to regulate power supply and demand from renewable energy, which fluctuates depending on weather and time of day, contributing to carbon neutrality."
https://newsroom.mazda.com/en/publicity/release/2025/202508/250821a.html
Sounds like good news for the future of both EVs and renewable energy.
Old EV batteries could potentially be either recycled or become part of a renewable grid, depending on which made more sense.
Cheers,
James.
PS: I'm enjoying Not the End of the World & looking forward to your new book, this month!
Great article! A couple questions come to mind:
1. I initially installed a level 2 charger at my home, but realized I can get by with level 1 charging most of the time. Is there any difference on my battery degradation?
2. I recently got a TM3 with an LFP battery, they recommend charging to 100% regularly - thoughts?
Question: does battery degradation affect efficiency? E.g. if a battery degrades to 80% of original capacity, does it require 80% as many kWh to charge it (no loss of efficiency), or does it still require the same amount of energy to charge it (with energy somehow being lost in the charging or discharging process)?
These are good question to ask indeed! Can car with say 80% battery capacity have same performance as new one(sufficient)? Is degradation fairly linear of is it becoming catastrophic after some point? Large battery on EV degraded to, lets say 50% would still offer good city driving range for years to come unless it cannot be used(significant performance drop), or becomes fire hazard, or cannot support enough "umpf" when accelerating. These are details that matter.
There’s a podcast called Catalyst that did an episode on repurposing EV batteries for electrical grid storage. They talked about the high capacities of the second hand batteries they received, as well as the economics and challenges of EV battery repurposing. A very interesting extension of what you talk about in this article!
Do you have a similar study for ‘home’ batteries ?