Warranty vs Mileage vs Battery

bobs2293

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I test drove an MG5 LR today and was very impressed.

I have the opportunity to get one through salary sacrifice as a company car for £383 a month for 4 years with a mileage limited of 35k per annum. This would include all servicing and repairs.

I drive a lot for work.

My big question that’s bugging me is this:

I have noted in the small print of the MG warranty that they don’t class a fault with the battery until it’s drops below 70% on a capacity check. Which translates as a 30% loss of range.

Now clearly after 3 or so years into my agreement I’d have over 100k on the clock and i can imagine the battery would start having issues…..and with the loss of range make the car a pain! I’m assuming they’d refuse to fix it until it got really bad.

Whats your thoughts?

Anyone hit high mileage?

Anyone dealt the a warranty claim?

Thanks!
 
Can't speak specifically for MG, or even be scientific with an answer, but I've been around EV forums quite a bit in the past 3 or so years and as far as I recall the number of serious battery issues, especially at that age and mileage, has been negligible. I can only recall one in fact, but my memory says even that wasn't age or mileage related, and it was replaced under 7 year warranty.
 
I test drove an MG5 LR today and was very impressed.

I have the opportunity to get one through salary sacrifice as a company car for £383 a month for 4 years with a mileage limited of 35k per annum. This would include all servicing and repairs.

I drive a lot for work.

My big question that’s bugging me is this:

I have noted in the small print of the MG warranty that they don’t class a fault with the battery until it’s drops below 70% on a capacity check. Which translates as a 30% loss of range.

Now clearly after 3 or so years into my agreement I’d have over 100k on the clock and i can imagine the battery would start having issues…..and with the loss of range make the car a pain! I’m assuming they’d refuse to fix it until it got really bad.

Whats your thoughts?

Anyone hit high mileage?

Anyone dealt the a warranty claim?

Thanks!
I hate to break this to you but the warranty is 7 years or 80k miles so it won't be covered at a 100k. With repairs being included in your deal you need to find out what metric they are going to use to define a battery "fault" it may be completely different to the warranty metric of 70%.
 
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You might find this article interesting. They tested a SAIC produced EV battery that was 8 years old with 575,000km on it and it still had 85% of it's capacity!


It's my understanding that SAIC produce CATL batteries under license. CATL batteries are used in BMW, Tesla, VW and Volvo cars.

 
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I test drove an MG5 LR today and was very impressed.

I have the opportunity to get one through salary sacrifice as a company car for £383 a month for 4 years with a mileage limited of 35k per annum. This would include all servicing and repairs.

I drive a lot for work.

My big question that’s bugging me is this:

I have noted in the small print of the MG warranty that they don’t class a fault with the battery until it’s drops below 70% on a capacity check. Which translates as a 30% loss of range.

Now clearly after 3 or so years into my agreement I’d have over 100k on the clock and i can imagine the battery would start having issues…..and with the loss of range make the car a pain! I’m assuming they’d refuse to fix it until it got really bad.

Whats your thoughts?

Anyone hit high mileage?

Anyone dealt the a warranty claim?

Thanks!
Under the warranty dealers have a deterioration curve from 100% down to say 70% at 80k miles, I have seen the Nissan one.

The reality though is that a single cell will fail and a fix by say Cleevely EV wouldn't be that expensive anyway. On the LEAF it's a one day job.

Follow this thread: -

It talks about maintaining your battery in good health.

Basically try to keep your battery in the 20-80% range, charge when needed and not by habit, avoid going over 80% on rapids.

Follow James & Kate and Cleevely, they use an MG5 just like you intend, with probably higher mileages than you too!
 
The complication with that high mileage is that you'll likely be rapid charging a lot, which will accelerate the degradation to a degree.

In practice, most EV batteries (especially those with active thermal management - like the MGs) don't seem to drop off a cliff, it's more a slow and steady decline. And much of the degradation is related to time rather than use, so the 'calendar degradation' won't be as great as for an older EV.

My suggestion would be to take it on a shorter lease so that you limit the period of ownership where you'll be outside the battery warranty.
 
I test drove an MG5 LR today and was very impressed.

I have the opportunity to get one through salary sacrifice as a company car for £383 a month for 4 years with a mileage limited of 35k per annum. This would include all servicing and repairs.

I drive a lot for work.

My big question that’s bugging me is this:

I have noted in the small print of the MG warranty that they don’t class a fault with the battery until it’s drops below 70% on a capacity check. Which translates as a 30% loss of range.

Now clearly after 3 or so years into my agreement I’d have over 100k on the clock and i can imagine the battery would start having issues…..and with the loss of range make the car a pain! I’m assuming they’d refuse to fix it until it got really bad.

Whats your thoughts?

Anyone hit high mileage?

Anyone dealt the a warranty claim?

Thanks!
35k/year means 134 miles/working day on average, real life range is 180 miles (I own same car and half my miles are on motorway) which means if battery capacity drops to 74% you will have to stop and recharge it during the day (sooner when you do more than 134 miles a day).

Look at 3 year contract, with this kink of mileage you have to go electric.
 
35k/year means 134 miles/working day on average, real life range is 180 miles (I own same car and half my miles are on motorway) which means if battery capacity drops to 74% you will have to stop and recharge it during the day (sooner when you do more than 134 miles a day).

Look at 3 year contract, with this kink of mileage you have to go electric.
Do you have the LR or the SR?
 
I have noted in the small print of the MG warranty that they don’t class a fault with the battery until it’s drops below 70% on a capacity check. Which translates as a 30% loss of range.

ok - lets follow that up with a question for anyone that's more battery minded. I (like most people) look at that and think (does that mean I can lose 29% of my range and have no comeback on warranty, but should we be thinking of this as more binary than linear (i.e. it's either a good battery or a duff one?) (Yeah, I realise there's lots of cells and it's not as simple as that, but bear with me)

Looking at this another way - I would expect that there's no way they would put the figure at 70% if there was a chance that normal battery wear would get anywhere near that during the lifetime of the warranty. Perhaps that's just a figure to pin it on, but the reality is that if the battery is fine it'll be nowhere near that level of degradation, but if it isn't, it'll plummet to well below the 70% mark?

I'm thinking along the lines of the balancing problem in one of the ZS BMS versions - there seems to be clear issues of range dropping well within a year that must've triggered this as a 'warranty' issue (albeit not a physical battery replacement though)
 
Surely if you do the proposed mileage any car would be on its knees by then. Having said that YTube Bjorn Nyland has a 7 year old Tesla model S with 250,000kms on it with not too bad degradation.
 
Surely if you do the proposed mileage any car would be on its knees by then. Having said that YTube Bjorn Nyland has a 7 year old Tesla model S with 250,000kms on it with not too bad degradation.
Ideal scenario for leasing if the numbers are right. Teslas hold their SOH better than anybody else with historic data to prove it.
I can only speculate what a car that first came out 2 years ago would be after 7 years.
 
Ideal scenario for leasing if the numbers are right. Teslas hold their SOH better than anybody else with historic data to prove it.
I can only speculate what a car that first came out 2 years ago would be after 7 years.
I think that covers most EVs (not Leaf) other than Tesla. :) so hopefully they will hold their SOH just as well.
 
Nissan have been running the Leaf since 2010 and have sold particularly well in the Scandinavian countries. What they have found is the longevity and reliability of their batteries has been considerably better than they envisaged and they now come as standard with an 8 year warranty to provide 80% capacity. The original model handbook specifically stated not to routinely recharge the battery if above 80% state charge unless specifically needed. Likewise avoid the use of rapid charging unless actually required. The new model has improved BMS so the 80% SOC rule is no longer mentioned.

I have no specific reference but these rules seem to be widely recognised and about the best to follow.
 
ok - lets follow that up with a question for anyone that's more battery minded. I (like most people) look at that and think (does that mean I can lose 29% of my range and have no comeback on warranty, but should we be thinking of this as more binary than linear (i.e. it's either a good battery or a duff one?) (Yeah, I realise there's lots of cells and it's not as simple as that, but bear with me)

Looking at this another way - I would expect that there's no way they would put the figure at 70% if there was a chance that normal battery wear would get anywhere near that during the lifetime of the warranty. Perhaps that's just a figure to pin it on, but the reality is that if the battery is fine it'll be nowhere near that level of degradation, but if it isn't, it'll plummet to well below the 70% mark?

I'm thinking along the lines of the balancing problem in one of the ZS BMS versions - there seems to be clear issues of range dropping well within a year that must've triggered this as a 'warranty' issue (albeit not a physical battery replacement though)
Nissan have a graph based on age / mileage for range loss. If you fall below the line, they act, if you are above the don't.


1642109954357.png


MG state 70% after 7 years, so will have a similar graph.
 
I know you don't know how it works, but I wonder if for someone only doing 6250 miles a year the final %age will be 85% or thereabouts.

I expect a cleverer person than me can work out what that equation means... :)
 
I know you don't know how it works, but I wonder if for someone only doing 6250 miles a year the final %age will be 85% or thereabouts.

I expect a cleverer person than me can work out what that equation means... :)
That graph is for the LEAF which is the worst battery in existence due to its lack of battery coolant.

All others are better!

Sounds like you need to take your MG5 on tour round Europe!
 
Interesting it seems to indicate that it levels off as time progresses. I expected it to continue to fall, as the car ages, ultimately becoming unusable. It would imply that once you get to about 8 years, if you're happy with that capacity,(which is probably good enough for a lot of uses), you can use it for as long as the car lasts ?

Is this a wildly simplistic assessment ?
 
Interesting it seems to indicate that it levels off as time progresses. I expected it to continue to fall, as the car ages, ultimately becoming unusable. It would imply that once you get to about 8 years, if you're happy with that capacity,(which is probably good enough for a lot of uses), you can use it for as long as the car lasts ?

Is this a wildly simplistic assessment ?
What has happened with early super high mileage cars is that the LEAF follows that curve then seems to have a battery cell failure c 250,000 miles and owners tend to replace the battery with a larger capacity one. Ex Norway battery packs from crashed LEAFs abound at reasonable prices.

Tesla batteries seem to have a cell failure around 450,000+ miles that requires a unit to be replaced or a new battery. That is a good guide for an MG that's been looked after, much less of course with daily 100% charging.

In all cases the minimum work required is to replace a failed cell block & rebalance the battery maintaining the capacity lost. 4-8 hours work & a second hand cell pack.
 
What has happened with early super high mileage cars is that the LEAF follows that curve then seems to have a battery cell failure c 250,000 miles and owners tend to replace the battery with a larger capacity one. Ex Norway battery packs from crashed LEAFs abound at reasonable prices.

Tesla batteries seem to have a cell failure around 450,000+ miles that requires a unit to be replaced or a new battery. That is a good guide for an MG that's been looked after, much less of course with daily 100% charging.

In all cases the minimum work required is to replace a failed cell block & rebalance the battery maintaining the capacity lost. 4-8 hours work & a second hand cell pack.
With no mechanical understanding of how the batteries are accessed in the mg5, is the process designed to be easily done? It sounds like something beyond the skills of a fitter at a dealer.
 
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