Hypothesis on Recuperation and Charging Profile

JimBob

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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.
But he seems to be saying he is not getting any regenerative braking or maybe very little. He needs to post his battery temperature to determine if there actually is a problem. Maybe a 20 mile trip wasn't long enough to get the battery temp up if the temperature was only a little above freezing. Actually just cruising along doesn't raise the battery temperature very much when its cold outside.
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Don't mix up English "Direct Charging" and "Direct Current".
Direct Current = DC = Gleichstrom = voltage does not alternate between - and + relative to ground
Direct Charging = Direkt Laden

As stated, if you plug into a DC charger, all charging profiles, limits, timers, target states of charge, etc. are ignored. I agree with Kingske here - the assumption is probably one or both of a) you want 100% since you are on a longer trip; and/or b) you will be keeping an eye on the charging and can stop it when you want.

Also note that none of this has anything to do with regenerative braking. I agree with andrewket here on the temperature, and would also add in that above 80% even at ideal temperature the battery pack can't take the full 265 kW of regen the Taycan motors can produce.
 
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But he seems to be saying he is not getting any regenerative braking or maybe very little. He needs to post his battery temperature to determine if there actually is a problem. Maybe a 20 mile trip wasn't long enough to get the battery temp up if the temperature was only a little above freezing. Actually just cruising along doesn't raise the battery temperature very much when its cold outside.
Thank you. Battery was preheated to 12 C (writing from my phone no easy way to convert it to F for courtesy) and as you state it, it was either exactly no regain or later then well in the whatsoever expected range.
 

JimBob

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Thank you. Battery was preheated to 12 C (writing from my phone no easy way to convert it to F for courtesy) and as you state it, it was either exactly no regain or later then well in the whatsoever expected range.
I can handle C. Am ambidextrous.

The 12C is not hot enough to generate much effect from regenerative braking. You want to be closer to 25C and higher. To get full effect the battery needs to be cooking.
 

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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.
This may help. I had a Tesla Model S for many years. When I would charge to 100% or approach maximum charging I noticed that there was little or no feeling of regeneration when I applied the brakes. I spoke with Tesla and was told there is no regeneration until the battery actually needs to be regenerated.

When the level of charge began to run down I could feel regen. Because the Taycan is set up to avoid the feel of "one pedal driving" we don't feel the difference when regeneration is operative when we apply the brakes, but I suspect the same result is occurring. When the battery is close to a full charge there would be no regen. As the charge level goes down regeneration increases with braking even though we cannot feel that occurring.

Maybe this is obvious, but it may add to this discussion.
 

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Don't mix up English "Direct Charging" and "Direct Current".
Direct Current = DC = Gleichstrom = voltage does not alternate between - and + relative to ground
Direct Charging = Direkt Laden

As stated, if you plug into a DC charger, all charging profiles, limits, timers, target states of charge, etc. are ignored. I agree with Kingske here - the assumption is probably one or both of a) you want 100% since you are on a longer trip; and/or b) you will be keeping an eye on the charging and can stop it when you want.

Also note that none of this has anything to do with regenerative braking. I agree with andrewket here on the temperature, and would also add in that above 80% even at ideal temperature the battery pack can't take the full 265 kW of regen the Taycan motors can produce.
Note that the maximum regen is consistent with the max power allowed when DC charging at a ultrafast station. Obviously all the stars have to align: appropiate SOC and battery temp and an energic push of the brakes.
 

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This may help. I had a Tesla Model S for many years. When I would charge to 100% or approach maximum charging I noticed that there was little or no feeling of regeneration when I applied the brakes. I spoke with Tesla and was told there is no regeneration until the battery actually needs to be regenerated.

When the level of charge began to run down I could feel regen. Because the Taycan is set up to avoid the feel of "one pedal driving" we don't feel the difference when regeneration is operative when we apply the brakes, but I suspect the same result is occurring. When the battery is close to a full charge there would be no regen. As the charge level goes down regeneration increases with braking even though we cannot feel that occurring.

Maybe this is obvious, but it may add to this discussion.
All true, with a small correction. The battery pack doesn’t “need regeneration”. If it’s at 100% SOC there is no capacity for additional energy. As a result, the car can’t regen. On Teslas this is shown with yellow dots on the energy meter.
 

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All true, with a small correction. The battery pack doesn’t “need regeneration”. If it’s at 100% SOC there is no capacity for additional energy. As a result, the car can’t regen. On Teslas this is shown with yellow dots on the energy meter.
Which is why I mentioned state of charge... it must be probably below 25% to achieve values over 250kw...
 

NormF

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My recuperation always works, even right after an 85% charge. Temperature is not a factor as my Turbo is currently parked outside in weather that has been as low as -15C.
 

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This may help. I had a Tesla Model S for many years. When I would charge to 100% or approach maximum charging I noticed that there was little or no feeling of regeneration when I applied the brakes. I spoke with Tesla and was told there is no regeneration until the battery actually needs to be regenerated.
the tesla would not allow any regeneration when the battery is at a high SOC, there is nowhere for the kw from regeneration to be put
 

andrewket

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My recuperation always works, even right after an 85% charge. Temperature is not a factor as my Turbo is currently parked outside in weather that has been as low as -15C.
It’s not binary - regen at 10kW is still technically regen braking. Temperature absolutely will factor into it at some point. This is one of the advantages to Porsche’s strategy vs Tesla with respect to using the brake pedal for all braking. The driver tells the car how much braking force they want, and the car figures out the combination of regen and friction braking to fulfill the request. It’s seamless and the driver doesn’t have to change their driving style based on SOC or weather. The experience is consistent, which is important in a sports car.

With Tesla, you absolutely have to be aware of the SOC and how much regen is available. Many Tesla drivers have been caught off guard at very high SOCs and cold temperatures.
 
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