How long do you expect your EV's battery to last?
Discussion
What are people's expectations regarding the longevity of battery packs in their electric vehicles?
I got to use a tesla model S (85D) for a few days last year, and was impressed by the performance and practicality on offer. Compared to my XFR, it offers an easier-to-access boot, can carry 7 people (if 2 of them are small) and provides more legroom in the rear middle: all whilst offering similar performance for a fraction of the (running) costs of my jag. The range (up to 250 miles) is also broadly comparable, and with fast charging improving rapidly I am now confident that the range offered would meet my needs. So I have no qualms with general usability.
My one remaining (potential) problem is that I would only be in the market for one once they've depreciated lots (lost 80% of new value, so probably about 8-10yrs old). I would also want to keep it for a good long time too, however from what (little) I (think I) know about battery technology I am concerned that the current Tesla batteries would reach the recharge cliff at some point from 8-20yrs old, which would leave me with a potential £££ bill. Such battery behaviour would also (I presume) affect resale values for owners of current cars, so I imagine there are current owners that will have done some research on this topic and provide some data input to the subsequent discussion.
I got to use a tesla model S (85D) for a few days last year, and was impressed by the performance and practicality on offer. Compared to my XFR, it offers an easier-to-access boot, can carry 7 people (if 2 of them are small) and provides more legroom in the rear middle: all whilst offering similar performance for a fraction of the (running) costs of my jag. The range (up to 250 miles) is also broadly comparable, and with fast charging improving rapidly I am now confident that the range offered would meet my needs. So I have no qualms with general usability.
My one remaining (potential) problem is that I would only be in the market for one once they've depreciated lots (lost 80% of new value, so probably about 8-10yrs old). I would also want to keep it for a good long time too, however from what (little) I (think I) know about battery technology I am concerned that the current Tesla batteries would reach the recharge cliff at some point from 8-20yrs old, which would leave me with a potential £££ bill. Such battery behaviour would also (I presume) affect resale values for owners of current cars, so I imagine there are current owners that will have done some research on this topic and provide some data input to the subsequent discussion.
At that age, the battery will probably be the least of the problems. Anything going wrong will make them uneconomic to repair - they will be like tablets. There maybe a point at which faulty part swapping may become quick and easy, but I don't see it - its going to be nothing like an ICE car.
mattcov said:
At that age, the battery will probably be the least of the problems. Anything going wrong will make them uneconomic to repair - they will be like tablets. There maybe a point at which faulty part swapping may become quick and easy, but I don't see it - its going to be nothing like an ICE car.
i would say the opposite, less moving parts, no oily bits, no cam belts, no crank bearings.it will be down to build quality of the bits that all cars have and suspension wear.
It will get to the point where battery backs will be fixable by easily swapping out the cells that are faulty rather than the whole thing,
I think that’s a good question and one that is really hard to answer. All the evidence so far suggests that battery life with use is far far better than the manufacturers had initially planned for, which is good news of course, we’ve not seen 8 to 10 years of time on the current technology yet, so overall, probably a good positive indicator. As far as replacement cells or batteries in the future....again, an interesting question. Main thing to my mind will be if the current battery technology is still around when you need a replacement. Be nice to think that the manufacturers would offer something, but after 10 years they have no obligation. If the cells used in your battery pack are no longer manufactured in large numbers, it won’t be cheap to replace. Then again, an alternative might be on offer?
As a contrast, consider a high end ICE car for a moment. Say an AMG Merc with the big V8 that had head bolt issues. Yes it’s fixable, but if you ask Merc they want tens of thousands for a new engine. DIY is possible but very expensive, so in practice, it tends to scrap the car.
The mechanical drive elements of an EV are simple, the electronics other than the HV battery and speed controller/charging are going to be pretty much the same as any modern car as are the suspension etc.
Overall, I think an older EV could be a good shout as long as you are able to get a good indication of the battery capacity before buying. Probably easier to get a decent idea of health than with an ICE actually.
I was looking into used Lexus hybrids a while back and at a certain age, they were tending to suffer battery pack failure. Given they used small NiMh packs, that wasn’t really a surprise. An aftermarket replacement was about £800 fitted and guaranteed so as long as you budgeted for that, no problem.
I’m just glad my C350e hybrid has a decent warranty on the ‘e’ bit!
As a contrast, consider a high end ICE car for a moment. Say an AMG Merc with the big V8 that had head bolt issues. Yes it’s fixable, but if you ask Merc they want tens of thousands for a new engine. DIY is possible but very expensive, so in practice, it tends to scrap the car.
The mechanical drive elements of an EV are simple, the electronics other than the HV battery and speed controller/charging are going to be pretty much the same as any modern car as are the suspension etc.
Overall, I think an older EV could be a good shout as long as you are able to get a good indication of the battery capacity before buying. Probably easier to get a decent idea of health than with an ICE actually.
I was looking into used Lexus hybrids a while back and at a certain age, they were tending to suffer battery pack failure. Given they used small NiMh packs, that wasn’t really a surprise. An aftermarket replacement was about £800 fitted and guaranteed so as long as you budgeted for that, no problem.
I’m just glad my C350e hybrid has a decent warranty on the ‘e’ bit!
I fail to understand why people are so concerned about "the battery" in an EV? In your ICE, after it's out of warranty (a max of 5 years, 100kmiles, but typically just 3 years, 60kmiles) you have a hugely complex, very expensive to fix mechanical device which just like your EV is designed for a nominal 150k miles and 10 year life (on average). And, just like an EV battery, every time you use it, it wears out a bit more, ie it uses up some of it's life.
This is fundamentally why an ICE car with say 130k miles on the clock is essentially worthless, because at any moment it might go bang in a ruinously expensive way.
But, because an EV has a much simpler powertrain (many, many fewer moving parts to wear out) and because the battery not only self diagnoses but also publishes that information, you could buy a 130kmile EV at a much lower level of risk! Added to which, a battery swap in an EV is actually a very simply process. A few bolts, some connectors and a large jack and it's out. Compared to removing and repairing the powertrain in a modern ICE (something that pretty much never happens due to the cost to do it) reconditioning the battery of an EV is easy to do. It won't be long, imo, before companies pop up that offer just this service!
(what could occur imo, is that second use sourcing for crash damaged and EOL EV batteries will actually make the battery more valuable than the car itself before long!)
This is fundamentally why an ICE car with say 130k miles on the clock is essentially worthless, because at any moment it might go bang in a ruinously expensive way.
But, because an EV has a much simpler powertrain (many, many fewer moving parts to wear out) and because the battery not only self diagnoses but also publishes that information, you could buy a 130kmile EV at a much lower level of risk! Added to which, a battery swap in an EV is actually a very simply process. A few bolts, some connectors and a large jack and it's out. Compared to removing and repairing the powertrain in a modern ICE (something that pretty much never happens due to the cost to do it) reconditioning the battery of an EV is easy to do. It won't be long, imo, before companies pop up that offer just this service!
(what could occur imo, is that second use sourcing for crash damaged and EOL EV batteries will actually make the battery more valuable than the car itself before long!)
Jag_luvver said:
My one remaining (potential) problem is that I would only be in the market for one once they've depreciated lots (lost 80% of new value, so probably about 8-10yrs old).
The truth is no one knows for sure. The original Tesla roadster was launched in 2008, so the early car are coming up to 10 years old. Unfortunately not many of those cars were ever made so getting a good 'fleet' average of degradation is difficult. But what is clear owner aren't reporting catastrophic loss of range, I certainly haven't seen any stories to that effect, and I can be sure if that was the case the anti-EV brigade would be pushing it every opportunity. As someone whos bought a Tesla with a plan to own it longterm, battery degradation isn't something I'm worried about. I fully expect the battery in our Model X to last long enough for my days as been daddy taxi to stop.....my daughter is currently 20 months old
......Those Falcon Wing doors are a different matter!!Ok I seem to have found some info on current (2017 year) roadster battery performance on the very early 2008 cars.
Its a bit confusion as Tesla offer lots of different ways to display range, and never really show you the available kWh (no EVs do this I don't think).
What it looks like 10 year use, and most owner reporting well over 90% capacity retained with no sharp drop offs, so surprisingly good long term life. I would expect current S/X battery packs to last even better as battery thermal management in the S/X is much more advanced than the original roadster.
https://www.reddit.com/r/teslamotors/comments/5zy9...
Its a bit confusion as Tesla offer lots of different ways to display range, and never really show you the available kWh (no EVs do this I don't think).
What it looks like 10 year use, and most owner reporting well over 90% capacity retained with no sharp drop offs, so surprisingly good long term life. I would expect current S/X battery packs to last even better as battery thermal management in the S/X is much more advanced than the original roadster.
https://www.reddit.com/r/teslamotors/comments/5zy9...
I’m sure part of the problem about the perception of batteries being a potential timebomb is our general experiences with batteries (or more often, single cells) in consumer devices, and the assumption that an EV battery will be just the same. This assumption is wrong of course, given just how much effort manufacturers have put into monitoring and conditioning, things you simply don’t get on consumer devices.
Thanks for the replies. In my mind I drew the following parallels:
ICE -> electric motors
Fuel tank -> battery
so the batteries represent an expensive item (above-and-beyond typical running expenses) that I felt would be more likely to need replacement than a fuel tank: I read one article that suggested the cost of replacement tesla batteries are 'projected' to drop to $12k for a replacement (currently double that?). Replies that liken the battery to the engine highlight their comparability when in comes to the cost of replacement, but based on my experience of batteries I'd still rate the probably longevity of an ICE above batteries. This mindset, it is becoming increasingly apparent, is wrong! I think the source of my original skepticism is entirely down to laptop/mobile phone battery use experience (as suggested above), and from reports of early hybrid cars having to have battery replacements every 5 years.
The youtube video was very useful - I'd seen the capacity vs milage data before, but it mentions age degradation effects on capacity (0.3% p/a) which was one area I hadn't been able to find information about. Also, the tesla roadsters having around 90% capacity after 8yrs suggests (with a very simple extrapolation) 80% would be a further 8yrs down the line, at which point, I believe, batteries tend to reach the capacity cliff.
So, looks like now I just need to wait for another 4 years for their prices to drop
ICE -> electric motors
Fuel tank -> battery
so the batteries represent an expensive item (above-and-beyond typical running expenses) that I felt would be more likely to need replacement than a fuel tank: I read one article that suggested the cost of replacement tesla batteries are 'projected' to drop to $12k for a replacement (currently double that?). Replies that liken the battery to the engine highlight their comparability when in comes to the cost of replacement, but based on my experience of batteries I'd still rate the probably longevity of an ICE above batteries. This mindset, it is becoming increasingly apparent, is wrong! I think the source of my original skepticism is entirely down to laptop/mobile phone battery use experience (as suggested above), and from reports of early hybrid cars having to have battery replacements every 5 years.
The youtube video was very useful - I'd seen the capacity vs milage data before, but it mentions age degradation effects on capacity (0.3% p/a) which was one area I hadn't been able to find information about. Also, the tesla roadsters having around 90% capacity after 8yrs suggests (with a very simple extrapolation) 80% would be a further 8yrs down the line, at which point, I believe, batteries tend to reach the capacity cliff.
So, looks like now I just need to wait for another 4 years for their prices to drop
Edited by Jag_luvver on Friday 5th January 22:53
Max_Torque said:
t won't be long, imo, before companies pop up that offer just this service!
They already are doing this in the US with Prius* batteries - probably in the UK and elsewhere too - I haven't looked.* IMO making an older Prius a very attractive proposition for low-cost, low running cost motoring, but few seem to have twigged this.
gangzoom said:
Ok I seem to have found some info on current (2017 year) roadster battery performance on the very early 2008 cars.
Its a bit confusion as Tesla offer lots of different ways to display range, and never really show you the available kWh (no EVs do this I don't think).
What it looks like 10 year use, and most owner reporting well over 90% capacity retained with no sharp drop offs, so surprisingly good long term life. I would expect current S/X battery packs to last even better as battery thermal management in the S/X is much more advanced than the original roadster.
https://www.reddit.com/r/teslamotors/comments/5zy9...
Doesn't the actual capacity start much higher though? So it's lost much more than 10% in real terms.Its a bit confusion as Tesla offer lots of different ways to display range, and never really show you the available kWh (no EVs do this I don't think).
What it looks like 10 year use, and most owner reporting well over 90% capacity retained with no sharp drop offs, so surprisingly good long term life. I would expect current S/X battery packs to last even better as battery thermal management in the S/X is much more advanced than the original roadster.
https://www.reddit.com/r/teslamotors/comments/5zy9...
jimPH said:
Doesn't the actual capacity start much higher though? So it's lost much more than 10% in real terms.
Dont quite follow. The reported range of the car is directly calculated from remaining capacity.
Any change in range has a linear relationship with battery capacity. A change in battery capacity of 10% will cause a fall of 10% in range.
jimPH said:
Doesn't the actual capacity start much higher though? So it's lost much more than 10% in real terms.
I think you're referring to the electrical capacity and the useable capacity?It depends entirely on how the manufacturer intends to manage their batteries. Is lost battery capacity taken from the useable capacity or the buffer zone?
To answer the OPs question, I drive a Vauxhall Ampera. It has a 16.5kWh battery with 10.5kWh useable capacity. If my needs remain the same, I intend to keep the car until it is scrap value and hopefully convert the battery to a home energy storage solution.
The Ampera being a PHEV has no need to stress the battery to it's limits and has an active thermal management system and no rapid charging.
EV like the Leaf suffer battery degredation because they use a larger proportion of the battery, rapid charging and don't have active thermal management.
But as battery capacity increases users will be less inclined to rapid charge, won't need to charge to 100% (like Tesla allows users to manage now) and any loss in range will be less noticeable.
Evanivitch said:
It depends entirely on how the manufacturer intends to manage their batteries. Is lost battery capacity taken from the useable capacity or the buffer zone?
As far as I know all EV batteries only reduce usable kWh as degradation set in and the buffer zone remains static.JPJPJP said:
2500 - 3000 charge / discharge cycles before is started to become a problem
If it didn’t last that long, I would be disappointed if it wasn’t dealt with under warranty
The problem is that's almost as simplistic as the "motorway miles" discussion with an ICE.If it didn’t last that long, I would be disappointed if it wasn’t dealt with under warranty
High rate charging will be a lot more detrimental to a battery performance, per charge, than slow charging. Which is something that might become more obvious as we see more EV being used for taxi/courier work and typically using rapid chargers.
Gassing Station | EV and Alternative Fuels | Top of Page | What's New | My Stuff