Hypothesis on Recuperation and Charging Profile

AMERCY

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Then and when I wondered, why the "brake"-recuperation (not doing the one-pedal thing) would not set in.
Soothed myself with thoughts about the battery being to cold or so....
Now, outside temperatures are well above water freezing point (avoiding F/C here), and I went out for a longer (longer with respect to Corona) trip of 20mi.
Again, recuperation did not set in (no green pie when braking) - for a "long" while.
I started with SoC around 85% and recuperation somehow started at 80% down only. Then I remembered - my general charging profile, which was then most probably in effect; has a "minimum charge" set to 80% (having semantic issues here. or me, it behaves more as a charging cap - not a min).
So my otherwise unproven theory - especially for all that have observed recuperation setting in only after xxx mi:
Recuperation sets in only if SoC is below "maximum charge" of the active charging profile.
Any confirmation or invalidation welcome.
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Interesting theory. I assume you have sufficient KMs on your car to be past the initial brake pad bedding in phase. And if your theory holds, does the profile minimum SOC or timer maximum SOC affect this? Or both?

As a counter to your theory, I have not modified the general charging profile and thus have the default 25% SOC. I charge to 85% and have not seen what you describe. MY2020 Turbo.
 

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Then and when I wondered, why the "brake"-recuperation (not doing the one-pedal thing) would not set in.
Soothed myself with thoughts about the battery being to cold or so....
Now, outside temperatures are well above water freezing point (avoiding F/C here), and I went out for a longer (longer with respect to Corona) trip of 20mi.
Again, recuperation did not set in (no green pie when braking) - for a "long" while.
I started with SoC around 85% and recuperation somehow started at 80% down only. Then I remembered - my general charging profile, which was then most probably in effect; has a "minimum charge" set to 80% (having semantic issues here. or me, it behaves more as a charging cap - not a min).
So my otherwise unproven theory - especially for all that have observed recuperation setting in only after xxx mi:
Recuperation sets in only if SoC is below "maximum charge" of the active charging profile.
Any confirmation or invalidation welcome.
The only information I could quickly find was from the Taycan Owners Manual which seems to indicate that the charging profiles are active when using AC charging. This from the North American manual page 84.

Programming and activating the general charging
profile
The high-voltage battery is charged automatically to
the programmed charge level during the specified
charging times when the vehicle is charged using
alternating current (AC) and provided that no timer
or location-dependent charging profile is active.


Perhaps there is some other information that negates or modifies this when braking is applied? The profiles are not supposed to be active when DC charging is used and the braking is I believe, DC charging.

Check the battery temperature by what the dash displays. It can be quite different from the ambient temperature.
 
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AMERCY

AMERCY

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The only information I could quickly find was from the Taycan Owners Manual which seems to indicate that the charging profiles are active when using AC charging. This from the North American manual page 84.

Programming and activating the general charging
profile
The high-voltage battery is charged automatically to
the programmed charge level during the specified
charging times when the vehicle is charged using
alternating current (AC) and provided that no timer
or location-dependent charging profile is active.


Perhaps there is some other information that negates or modifies this when braking is applied? The profiles are not supposed to be active when DC charging is used and the braking is I believe, DC charging.

Check the battery temperature by what the dash displays. It can be quite different from the ambient temperature.
Hm. Whatever braking delivers - AC or DC, but: I would be very surprised if a restricting profile would NOT be in effect when charging thru DC Ionity or EA (... but had not yet the pleasure to see one of those in action). Hopefully those would NOT charge all the way thru to 100%, even if the general profile (or a potential specific one) being in effect.
Thank you!
 

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Hm. Whatever braking delivers - AC or DC, but: I would be very surprised if a restricting profile would NOT be in effect when charging thru DC Ionity or EA (... but had not yet the pleasure to see one of those in action). Hopefully those would NOT charge all the way thru to 100%, even if the general profile (or a potential specific one) being in effect.
Thank you!
All Settings for charging Profile and Timers are invalid when you charge at DC charging stations like Ionity. The car will be charged to 100% if you do not stop the charging. You can stop it in the car or with the connect app if you start the charge with the app.
 
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AMERCY

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All Settings for charging Profile and Timers are invalid when you charge at DC charging stations like Ionity. The car will be charged to 100% if you do not stop the charging. You can stop it in the car or with the connect app if you start the charge with the app.
That's something. Seems not logic to me - why are we advised to charge, if not on a road trip, only up to 80% SoC? Is only AC toxic in this sendse? Just thinking loud - I'm new to the EV stuff, and it seems then and when a little bit alchemic to a newcomer.
Thank you for clarifying.
 

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That's something. Seems not logic to me - why are we advised to charge, if not on a road trip, only up to 80% SoC? Is only AC toxic in this sendse? Just thinking loud - I'm new to the EV stuff, and it seems then and when a little bit alchemic to a newcomer.
Thank you for clarifying.
I guess the logic behind charging up to 100% at a roadside DC charger is based on the assumption that you continue your journey shortly thereafter and therefore do not leave it at 90-100% SoC for very long?
 
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AMERCY

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I guess the logic behind charging up to 100% at a roadside DC charger is based on the assumption that you continue your journey shortly thereafter and therefore do not leave it at 90-100% SoC for very long?
That's truely an interesting form of patronage.
 
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AMERCY

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Ah, and one more thing: When charging at a DC Charger (EA, Ionity or so), the the "direct charge" button on the middle "charging" display should be gone - or at least being grayed out, following the above described logic. Or the other way around: "Direct Charging" is available only when being plugged into an AC charger.
Wonder of wonder. For the elder among us: This is somehow like playing with a Tamagotchi :)
 

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Ah, and one more thing: When charging at a DC Charger (EA, Ionity or so), the the "direct charge" button on the middle "charging" display should be gone - or at least being grayed out, following the above described logic. Or the other way around: "Direct Charging" is available only when being plugged into an AC charger.
Wonder of wonder. For the elder among us: This is somehow like playing with a Tamagotchi :)
The DC button doesn't mean DC charging. It means Direct Charging. Overrides the profiles. The Germans wrote it. Ask them!
 

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That's something. Seems not logic to me - why are we advised to charge, if not on a road trip, only up to 80% SoC? Is only AC toxic in this sendse? Just thinking loud - I'm new to the EV stuff, and it seems then and when a little bit alchemic to a newcomer.
Thank you for clarifying.
I agree it is not logic at all. But there is quite a lot of SW in the PCM that defuse logic. Just look at Profile for charging. Setting a minimum level is actually a maximum level. Makes sense?
 

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I agree it is not logic at all. But there is quite a lot of SW in the PCM that defuse logic. Just look at Profile for charging. Setting a minimum level is actually a maximum level. Makes sense?
A bit like a salary negotiation: the minimum you demand is the maximum you get.
 
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AMERCY

AMERCY

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The DC button doesn't mean DC charging. It means Direct Charging. Overrides the profiles. The Germans wrote it. Ask them!
Understood it just as you say.
In German it's indeed
1613580808995.png
, which is "Direct Charging, where as "DC" would be "Gleichstrom" (forgive my smart-assing).
So the logic that would be expected "Direct Charging" Button is not active/available if charging on "DC" - only if charging on "AC".
Well, not so important, finally, but it's fun to find out the logic (assuming there exists one) behind that.
 

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Understood it just as you say.
In German it's indeed
1613580808995.png
, which is "Direct Charging, where as "DC" would be "Gleichstrom" (forgive my smart-assing).
So the logic that would be expected "Direct Charging" Button is not active/available if charging on "DC" - only if charging on "AC".
Well, not so important, finally, but it's fun to find out the logic (assuming there exists one) behind that.
Ok. Now I have a new button in German on my screen, which doesn't seem to do anything.
 

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Regenerative braking can generate 200kW+ of power. If the battery pack is cold, it can’t handle that - just like charging. So until the pack is warmed up, regenerative breaking will be reduced.
 
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