Life and Death of Li Ion batteries
Discussion
A little study shows Tesla battery capacity typically heading for the 80% watershed around 10 years:
https://www.nimblefins.co.uk/study-real-life-tesla...
Some science about Lithium batteries:
https://iopscience.iop.org/article/10.1149/1945-71...
Summary for shed drivers:
Once a battery is getting down to ~80% of new performance, failure mechanisms are accelerating and it's rapidly downhill.
https://www.nimblefins.co.uk/study-real-life-tesla...
Some science about Lithium batteries:
https://iopscience.iop.org/article/10.1149/1945-71...
Summary for shed drivers:
Once a battery is getting down to ~80% of new performance, failure mechanisms are accelerating and it's rapidly downhill.
SWoll said:
Why do you consider 80% a watershed?
A current Model 3 LR at 80% battery life would still be capable of 250 miles between charges. Hardly at the end of its useful life and still considerably more than many other EV's when new?
Anyone who’s owned an old iPhone knows it doesn’t work like that. They have about 20% of the performance at 80% capacity. Basically they are knackered which is why they are repurposed as part of somebody’s power wall. After that they are recycled.A current Model 3 LR at 80% battery life would still be capable of 250 miles between charges. Hardly at the end of its useful life and still considerably more than many other EV's when new?
wormus said:
Anyone who’s owned an old iPhone knows it doesn’t work like that. They have about 20% of the performance at 80% capacity. Basically they are knackered which is why they are repurposed as part of somebody’s power wall. After that they are recycled.
I suspect most EV's have a more advanced battery management system than 'an old iPhone'.OutInTheShed said:
A little study shows Tesla battery capacity typically heading for the 80% watershed around 10 years:
https://www.nimblefins.co.uk/study-real-life-tesla...
Some science about Lithium batteries:
https://iopscience.iop.org/article/10.1149/1945-71...
Summary for shed drivers:
Once a battery is getting down to ~80% of new performance, failure mechanisms are accelerating and it's rapidly downhill.
It's weird that you linked an article that doesn't support what you've written. Why is that?https://www.nimblefins.co.uk/study-real-life-tesla...
Some science about Lithium batteries:
https://iopscience.iop.org/article/10.1149/1945-71...
Summary for shed drivers:
Once a battery is getting down to ~80% of new performance, failure mechanisms are accelerating and it's rapidly downhill.
The cars at 8 years old had mileage far in excess of the average car mileage. Which suggests age isn't the determining factor alone.
It also doesn't support the idea that at 80% these vehicles are no longer useable.
It also ignores the change in Battery Management Systems and chemistry over the last 10 years.
wormus said:
Anyone who’s owned an old iPhone knows it doesn’t work like that. They have about 20% of the performance at 80% capacity. Basically they are knackered which is why they are repurposed as part of somebody’s power wall. After that they are recycled.
That's right, a small passively-cooled phone battery differs in no way at all to a large, liquid-cooled actively-managed 400V EV battery. In fact, I've got a Tesla battery stuck to my ear right now, that's how similar they are. What does 20% performance even mean?
wormus said:
SWoll said:
Why do you consider 80% a watershed?
A current Model 3 LR at 80% battery life would still be capable of 250 miles between charges. Hardly at the end of its useful life and still considerably more than many other EV's when new?
Anyone who’s owned an old iPhone knows it doesn’t work like that. They have about 20% of the performance at 80% capacity. Basically they are knackered which is why they are repurposed as part of somebody’s power wall. After that they are recycled.A current Model 3 LR at 80% battery life would still be capable of 250 miles between charges. Hardly at the end of its useful life and still considerably more than many other EV's when new?
It's not a time thing anyway, it's charge cycles, local temperatures, charging speeds etc. that affect EV degradation. Essentially a lot more complex than "at 8-10 years old it'll be finished" Could easily take 15+ years to get to that point for most normal users doing <10k a year, living in a moderate climate and rapid charging rarely.
SWoll said:
Why do you consider 80% a watershed?
A current Model 3 LR at 80% battery life would still be capable of 250 miles between charges. Hardly at the end of its useful life and still considerably more than many other EV's when new?
Because........Grrr, bloody Elon, erm, panel gaps.A current Model 3 LR at 80% battery life would still be capable of 250 miles between charges. Hardly at the end of its useful life and still considerably more than many other EV's when new?
SWoll said:
Why do you consider 80% a watershed?
A current Model 3 LR at 80% battery life would still be capable of 250 miles between charges. Hardly at the end of its useful life and still considerably more than many other EV's when new?
Because the decay (for want of a better word) is not linear.A current Model 3 LR at 80% battery life would still be capable of 250 miles between charges. Hardly at the end of its useful life and still considerably more than many other EV's when new?
As described in the second paper.
Once a cell is down to the 80% region, all the decay processes are accelerating and it's relatively short haul to 50% and then more quickly still to 10% and time for recycling.
This isn't about Teslas specifically, it's just that Teslas and Leaves have useful amounts of data.
80% is a vague consensus or average of the 'knee point' in the graph where decay steepens.
Different studies with different conditions and methods put the knee anywhere from 95 to 70%
GT9 said:
wormus said:
Anyone who’s owned an old iPhone knows it doesn’t work like that. They have about 20% of the performance at 80% capacity. Basically they are knackered which is why they are repurposed as part of somebody’s power wall. After that they are recycled.
That's right, a small passively-cooled phone battery differs in no way at all to a large, liquid-cooled actively-managed 400V EV battery. In fact, I've got a Tesla battery stuck to my ear right now, that's how similar they are. What does 20% performance even mean?
are you saying EV battery life is infinite? Here are some randomly selected facts to help with discussion https://www.midtronics.com/blog/do-electric-car-ev...Active battery management is a factor but so is the rate of (rapid) charge and discharge. It’s commonly accepted that an EV battery needs replacing every 10 years or 100k miles.
wormus said:
SWoll said:
Why do you consider 80% a watershed?
A current Model 3 LR at 80% battery life would still be capable of 250 miles between charges. Hardly at the end of its useful life and still considerably more than many other EV's when new?
Anyone who’s owned an old iPhone knows it doesn’t work like that. They have about 20% of the performance at 80% capacity. Basically they are knackered which is why they are repurposed as part of somebody’s power wall. After that they are recycled.A current Model 3 LR at 80% battery life would still be capable of 250 miles between charges. Hardly at the end of its useful life and still considerably more than many other EV's when new?
wormus said:
GT9 said:
wormus said:
Anyone who’s owned an old iPhone knows it doesn’t work like that. They have about 20% of the performance at 80% capacity. Basically they are knackered which is why they are repurposed as part of somebody’s power wall. After that they are recycled.
That's right, a small passively-cooled phone battery differs in no way at all to a large, liquid-cooled actively-managed 400V EV battery. In fact, I've got a Tesla battery stuck to my ear right now, that's how similar they are. What does 20% performance even mean?
are you saying EV battery life is infinite? Here are some randomly selected facts to help with discussion https://www.midtronics.com/blog/do-electric-car-ev...Active battery management is a factor but so is the rate of (rapid) charge and discharge. It’s commonly accepted that an EV battery needs replacing every 10 years or 100k miles.
Commonly accepted by you, perhaps. Who else?
wormus said:
It’s commonly accepted that an EV battery needs replacing every 10 years or 100k miles.
Is it? For which chemistry? LFP is capable of many more cycles than NMC, for example. So it would hardly be a hard and fast rule. The answer on battery replacement is more like 'it depends'. Batteries do degrade, no doubt about it. We had a Mk1 Leaf so know all about that - but it strikes me as becoming less and less of a problem going forward, particularly taking into account the average miles someone in the UK would do.
As someone pointed out due to the size of some of these packs even 80% remaining capacity would still give you a pretty useful vehicle.
wormus said:
Oh good, another thread to illicit irrational hatred from the EV freaks are you saying EV battery life is infinite? Here are some randomly selected facts to help with discussion https://www.midtronics.com/blog/do-electric-car-ev...
Active battery management is a factor but so is the rate of (rapid) charge and discharge. It’s commonly accepted that an EV battery needs replacing every 10 years or 100k miles.
The only irrational hatred is for people who talk b are you saying EV battery life is infinite? Here are some randomly selected facts to help with discussion https://www.midtronics.com/blog/do-electric-car-ev...Active battery management is a factor but so is the rate of (rapid) charge and discharge. It’s commonly accepted that an EV battery needs replacing every 10 years or 100k miles.
ks, hence you are often find yourself on the receiving end funnily enough. Commonly accepted by who BTW? You speak of EV batteries like they are all manufactured and used identically, which is ridiculous.
The article you link to mentions 1500 to 2000 full charge cycles, not time. For an EV with a 75kWh battery doing 3.5 miles/kwh that's 112,500 to 150,000 kWh, or enough to cover 500,000 miles. It then mentions the batteries are nothing like that found in a phone.
Also "Because of this cycle-aided degradation, the batteries will gradually lose its capacity. However, it may take nearly a decade for you to see any noticeable dips in performance."
I do find it funny you've posted a link that contradicts all of your previous statements.
Nomme de Plum said:
I buy my iPhones outright. We do not seem to be suffering the battery life/performance problem you allege.
So do I This is my 2 year old iPhone now, it has 80% capacity and it’s performance over the last 3 months has deteriorated massively to the point it won’t last a full day, my wife’s bought at the same time is even worse and literally lasts a couple of hours
It really don’t think the above example is unique at all, it’s worth reading the first paragraph below
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