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I almost bought a 19 plate egolf today but asked the dealer for a state of health report on the battery and it was only 94% at less than 6 month old and 4K mileage. I was concerned this was very high degradation and backed out.

Anyone know what is expected as annual degradation? Dealer could not offer further info like whether this just ate into the top buffer or whether the available energy was reduced.

Car is an ex-courtesy car also used by staff. Generally charged to 100% every day according to dealer.
 

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I've actually just bought an ex demo golf just under 6 months old and 3400 miles. Used every day by the sales manager for his commute.

I can't answer your question specifically about degradation, but I cannot get it to charge to it's supposed 144 mile range even though I am averaging 3.9 miles per kWh. 129 miles range has been the maximum so far with lowest full charge range 119 miles.
 

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I almost bought a 19 plate egolf today but asked the dealer for a state of health report on the battery and it was only 94% at less than 6 month old and 4K mileage. I was concerned this was very high degradation and backed out.

Anyone know what is expected as annual degradation? Dealer could not offer further info like whether this just ate into the top buffer or whether the available energy was reduced.

Car is an ex-courtesy car also used by staff. Generally charged to 100% every day according to dealer.
Despite what the EVangelists say here, if you charge to 100% every day and leave it there, you have no right not to expect this sort of degradation.

It's what li ion cells do.

Whether that represented a long term problem, or simply accelerated the first couple of year's degradation and it'd stay there for longer than an equivalent car, we just don't know enough about the life and times of Li battery packs yet.

As there is no industry standard 'recipe' and that it is always being changed these days, nor are we going to really understand that for 50 years.
 

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Is it possible the dealer has read off the state of charge at 100% charge as being 94% and passed this on as a degradation figure when in reality the soc at 100% as reported by the car is actually 95% due to the buffer, as users of obd11 have stated? This means degradation might be only 1% or possibly almost nothing if they charged the car in the current sub zero temperatures where I live, due to temperature related increased internal resistance.
 

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Can you ask him where he finds a SOH figure? I haven't found one in OBDeleven and would like to know if it VW do have one in there somewhere.

Our car was new in March 18 and has 37k miles on it. Max kWh I have seen as available was 32.2kWh iirc and in mid November it was 30.5kWh, just over 5% drop in 37k miles.
It's been charged to 100% most nights but isn't left sitting with a fully charged battery for more than an hour or three mostly.
 

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I will try and find out. They had recorded it as battery “depreciation”.

I suspect they see a very similar display to you on the obd11 app and they have misread the true SOC as SOH. I don’t think they have sold many egolfs and perhaps no one has asked them for a battery SOH before purchase before.
 

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I am averaging 3.9 miles per kWh. 129 miles range has been the maximum so far with lowest full charge range 119 miles.
With the current ambient temps and lower efficiency, you won’t see 144 miles on the GOM for a while. You’d need to be around 4.5 miles per kWh to see that.

It will go back up come the spring/summer, in the meantime at least you’re getting a reasonably accurate indication of your vehicles range each morning.
 

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You categorically cannot charge an e-Golf battery to 100%, the BMS won’t let you.

You can charge it to 89.4% though...
Yes, you can charge to 100% of what is allowed.

The point being that if you take a battery to its max every day and leave it there, it is not so good a thing to do.
Li cells always cycle longer if you cycle them closer to 50%. The electrodes physically take in li atoms, like a sponge, then let them go again. It is a physical cycle and the more extreme the SOC the more stretching and straining the electrodes have to do.

Lower SOC are actually worse still. Try not to go too low if you can help it.
 

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Yes, you can charge to 100% of what is allowed.

The point being that if you take a battery to its max every day and leave it there, it is not so good a thing to do.
Li cells always cycle longer if you cycle them closer to 50%. The electrodes physically take in li atoms, like a sponge, then let them go again. It is a physical cycle and the more extreme the SOC the more stretching and straining the electrodes have to do.

Lower SOC are actually worse still. Try not to go too low if you can help it.
Semantics.

You still cannot charge an e-Golf traction battery pack to its full capacity, 90% yes, but not 100%.

The other stuff is relevant and interesting, but the fact remains that a ‘full’ e-Golf is at 90% charged.
 

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Semantics.

You still cannot charge an e-Golf traction battery pack to its full capacity, 90% yes, but not 100%.

The other stuff is relevant and interesting, but the fact remains that a ‘full’ e-Golf is at 90% charged.
Semantics.

I never said it was/wasn't.
 

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Semantics.

I never said it was/wasn't.
You sure?

Despite what the EVangelists say here, if you charge to 100% every day and leave it there, you have no right not to expect this sort of degradation.
As this is an e-Golf thread, how are people supposed to read that then?

That’s why I felt it necessary to point out that you can’t charge an e-Golf battery to 100% anyway.

We like facts here on Speak EV. 👍
 

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You sure?



As this is an e-Golf thread, how are people supposed to read that then?

That’s why I felt it necessary to point out that you can’t charge an e-Golf battery to 100% anyway.

We like facts here on Speak EV. 👍
I feel the meaning is in the words "if YOU charge to 100%". It implies 100% of what you can charge to. It cannot have any other meaning. YOU don't know what the true 100% charge of the cell is so how could YOU do that?

Where did I say 'if the CELLS are charged to 100% every day'?

I did not mean to imply anything about the cell's capacity, only the users capacity to charge. I don't accept that is to be misunderstood, but it is now made clear.
 

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I feel the meaning is in the words "if YOU charge to 100%". It implies 100% of what you can charge to. It cannot have any other meaning. YOU don't know what the true 100% charge of the cell is so how could YOU do that?

Where did I say 'if the CELLS are charged to 100% every day'?

I did not mean to imply anything about the cell's capacity, only the users capacity to charge. I don't accept that is to be misunderstood, but it is now made clear.
More attempts at obfuscation and diversion, some things never change eh.

Thanks for the input on things that weren’t being asked though.
 

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On the contrary.

An assumption was made about what I said, and I clarified: If 'you' charge to 100% then clearly it means what is 100% possible for 'you'.

If you say 'I gave 100% to this marathon run' does that mean 100% of what 'you' can give it, or 100% of what the best marathon runner in the world can give? The 100% is clearly, and self-evidently, in the observational frame of the 'you', not of some technical matter over which that person had no control.

But in any case, it is now fully clarified and I am left wondering why you would want to try to 'prove me wrong'. Maybe you could explain why you thought that post helped anything?

Y'know, sometimes it takes a clarification for two people to understand each other. There is not remotely enough effort put into modern life for people to seek agreement and resolve where there may be misunderstandings.

Try it sometime, people. Two people can be right about something at the same time even if their statements are contradictory. One usually just has to resolve the axioms of meaning.
 

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PS ... it was the OP, the axiomatic basis of the thread itself, which provided the definition of what 'charging to 100%' meant.
 

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On the contrary.

An assumption was made about what I said, and I clarified: If 'you' charge to 100% then clearly it means what is 100% possible for 'you'.

If you say 'I gave 100% to this marathon run' does that mean 100% of what 'you' can give it, or 100% of what the best marathon runner in the world can give? The 100% is clearly, and self-evidently, in the observational frame of the 'you', not of some technical matter over which that person had no control.

But in any case, it is now fully clarified and I am left wondering why you would want to try to 'prove me wrong'. Maybe you could explain why you thought that post helped anything?

Y'know, sometimes it takes a clarification for two people to understand each other. There is not remotely enough effort put into modern life for people to seek agreement and resolve where there may be misunderstandings.

Try it sometime, people. Two people can be right about something at the same time even if their statements are contradictory. One usually just has to resolve the axioms of meaning.
:D:D Keep going!

It seems pretty clear that you were claiming that charging an EV to 100% was going to cause degradation, after somebody had posted about potential degradation on an e-Golf.

I was merely pointing out that you can’t, of course, charge an e-Golf to a true 100%. I think that was more helpful an answer to those who might be wondering if charging their e-Golf to 100% every day might expect the same.

It’s a shame that on the Speak EV Advent Calendar, the Day 1 window has the resident forum blow-hard/know it all* behind it, acting up as usual.

* delete as applicable.
 

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:D:D Keep going!

It seems pretty clear that you were claiming that charging an EV to 100% was going to cause degradation, after somebody had posted about potential degradation on an e-Golf.

I was merely pointing out that you can’t, of course, charge an e-Golf to a true 100%. I think that was more helpful an answer to those who might be wondering if charging their e-Golf to 100% every day might expect the same.

It’s a shame that on the Speak EV Advent Calendar, the Day 1 window has the resident forum blow-hard/know it all* behind it, acting up as usual.

* delete as applicable.
You can keep going down a hole but the OP was clear and was asking what happened if a car was charged to 100% very day.

As it is BLOODY OBVIOUS that this means where the battery is charged to the maximum capacity allowed, you are contradicting the OP and are therefore off topic.

What are you trying to prove here, by being so argumentative after the matter was fully clarified a few posts ago?
 

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You can keep going down a hole but the OP was clear and was asking what happened if a car was charged to 100% very day.

As it is BLOODY OBVIOUS that this means where the battery is charged to the maximum capacity allowed, you are contradicting the OP and are therefore off topic.

What are you trying to prove here, by being so argumentative after the matter was fully clarified a few posts ago?
Whilst it might be bloody obvious what the OP meant by 100% charged, in the context of your ‘assertion’ that that’s what you should expect when you charge a battery to 100%, it’s entirely relevant and not obvious that you can’t charge an e-Golf battery to 100%.

If you can’t see why that’s relevant to a discussion about ‘charging to 100%’, degradation and the e-Golf, I suggest you don’t comment.

Some EVs do allow the battery to be charged to 100% of their actual capacity, where your comment might be more applicable.
 
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