Is 100% really 88% full?

epirali

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More accurately you can charge without worrying, period. Batteries are designed, tested, and used with a good understanding of the degeneration curve. In fact Taycan like a lot of newer EVs have extensive thermal management as heat is one of the worst factors in battery life (besides cycles). They all set a lower level as “100%” after studying the battery life vs cycle vs maximum charge. So the margins not used both allow for optimal battery life vs capacity and allow regen even when charge is at “100” (which it really is not).
 

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More accurately you can charge without worrying, period. Batteries are designed, tested, and used with a good understanding of the degeneration curve. In fact Taycan like a lot of newer EVs have extensive thermal management as heat is one of the worst factors in battery life (besides cycles). They all set a lower level as “100%” after studying the battery life vs cycle vs maximum charge. So the margins not used both allow for optimal battery life vs capacity and allow regen even when charge is at “100” (which it really is not).
I think the confusion over this stems from the fact that Porsche said one should normally charge the battery only to 80% and when leaving the car stationary for long periods only to 50%. I hope that the manual of the car clarifies this, once I get my Taycan.
 

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More accurately you can charge without worrying, period. Batteries are designed, tested, and used with a good understanding of the degeneration curve. In fact Taycan like a lot of newer EVs have extensive thermal management as heat is one of the worst factors in battery life (besides cycles). They all set a lower level as “100%” after studying the battery life vs cycle vs maximum charge. So the margins not used both allow for optimal battery life vs capacity and allow regen even when charge is at “100” (which it really is not).
I would be curious how much juice is left when you hit zero, Read an article, that said Porsche had a buffer after zero like a ice gas reserve. And that when tesla says zero it means zero, that would be nice to know, I am sure we will find out once more are produced.
 

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I think the confusion over this stems from the fact that Porsche said one should normally charge the battery only to 80% and when leaving the car stationary for long periods only to 50%. I hope that the manual of the car clarifies this, once I get my Taycan.
I don’t know about the manual - but this is stated in my battery warranty papers.
 

epirali

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Most EVs (not including Tesla) including a small buffer at “zero” for usable power. The battery is never at zero, but even at fake zero they will give you a few miles to get to charging station (kind of like how ICE vehicles lie about distance to empty at zero). And its very hard to be very accurate about battery charge near full and empty so they don’t wan to be wrong and strand people.
 

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Ok so I just saw that on the app you can set departure time with target charge level. Seems to default to 85%. so I am guessing this is Porsches suggested battery charge level for longevity.
 

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Ok so I just saw that on the app you can set departure time with target charge level. Seems to default to 85%. so I am guessing this is Porsches suggested battery charge level for longevity.
OK, that would make sense. However, it would be nice to get some technical details about Porsche's internal testing of battery degradation depending on charging speed and level.
 

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OK, that would make sense. However, it would be nice to get some technical details about Porsche's internal testing of battery degradation depending on charging speed and level.
agreed. Given they recommend charging parameters basically like a Tesla (20-80% is ideal, not too low, not too high) I think it’s a mistake to assume the reserved capacity is simply a top buffer, or behaves in some linear way as unused capacity. We don’t know how it’s being used, and we don‘t know what charging to 100% daily will do to longevity other than Porsche doesn’t recommend it.
 

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Thanks @sneksis911, you motivated me to re-review my go-to charging video by Alex on Autos
https://youtu.be/vlrN-aS_jso

He charges from 1 to 100% against Porsche suggestions. Because he's Alex.
If you piece together the two charging sessions you get 89kw and figuring a modest 5% cable loss you get 84kw so I personally believe it hold back on charging the full pack.
 

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The usable battery is 83,7 kwh
Total is 93.4 kwh
You can not use the difference = 9.7kwh
 

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I would be curious how much juice is left when you hit zero, Read an article, that said Porsche had a buffer after zero like a ice gas reserve. And that when tesla says zero it means zero, that would be nice to know, I am sure we will find out once more are produced.
Hopefully someone will test this with the Taycan, obviously someone with AAA or a tow truck. :CWL::CWL::CWL:

German and Japanese ICE vehicles always have run at least 10-30 miles beyond "empty." Many many years ago I drove a friends Ford, and the minute it hit empty, I was stuck on the side of the interstate highway!

But I am highly skeptical that Porsche would leave another 10% reserve, and probably does not allow the use of the 9.7kwh that is in reserve, but again, hope someone will test it.
 

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The usable battery is 83,7 kwh
Total is 93.4 kwh
You can not use the difference = 9.7kwh
Seems an awful lot to have in reserve and not being used. And thinking of the cost for the 4S battery upgrade we pay for it but do not get anything for that reserve.

They must be super conservative with their estimate of battery life? Maybe they will release more of the capacity once they get real life feedback from cars being driven on the rods?
 

epirali

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Gents that is a very common amount of reserve for battery longevity. In fact it shows they are designing for long term life. Keep in mind they could release more capacity with updates as they have more data, like the ETron and I Pace did recently.
 

TriTaycan

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Do you set the charge level you want it to go to on an app or on the car or something? Or once you plug it in, does it just charge until full? (Which is really ~90% full).
 

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