Scheduled Departure Times ... What does it really do?

[SteveInKirkland]

There were some questions about what really happens when you set a planned departure time for the Macan EV and you have it plugged in for charging. This post is my experience from yesterday and today.

Yesterday at about 7 pm I plugged the Macan EV into a Level 2 AC charger in the USA (9.6kW). No departure times were set. The SoC at start was 63% the car was set to charge to a max of 80%. The car started to charge. There were no special considerations to attempt to charge the car between special hours. The car was sitting in a 66 F temperature controlled garage that maintained the temperature until the garage opened for the car to leave for the day.

A bit later, I set a departure time for 9:15 am and sent the changes to the car. The car's scheduled departure was set *not* to precondition the car's climate system. The SoC was 76%. The My Porsche app reported the car's charging status as Paused and the Level 2 charger reported 0 amps being delivered until much later in the morning.

At about 7:15 am, the car switched from Paused charging to charging at a non-peak rate (8 kW) The car finished charging prior to the planned departure and the battery temperature had been elevated to 71 F when I entered the car at 8:58 am and I left 17 minutes before the scheduled departure time.

On the 7th of February, I ran a similar test but, rather than adding a planned departure, I just let the car charge to 80%. It took max power (9.3 kW) from the wall throughout the charging session until it was finished and actually reported 81% SoC. When I left in the morning, no planned departure time set, the car's battery temperature was 64.

So ... observations:

(1) Planned departures do precondition the battery.
(2) The amps delivered to the car were not the peak possible. The car sipped power from the wall on its own schedule aligned with the departure time. It seemed to intentionally do this to raise the temperature of the battery.

I have screen shots and photos of the raw observations. If people are really interested in seeing the raw data, I can upload them. It just takes a bit of time. If you can think of another experiment to learn more, you're welcome to suggest it.

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[SergeyIndy]

Excellent experiment and analysis.

This works exactly as designed and similar to the Taycan with a few notes.

Preconditioning of the battery using Departure timer is a strong word since it goes up to 70F due to the charging process which is different from active preconditioning when you are navigating to a charger when the car heating the battery to 95F to accept fastest charging speed.

Departure target charging is basically gently charging the battery in sipping cycles as you mention to get it to the intended target if there is more time than necessary to reach that target. This is to say that it will be running at peak if the time to target is short.

 

[SteveInKirkland]

Preconditioning of the battery using Departure timer is a strong word since it goes up to 70F due to the charging process which is different from active preconditioning when you are navigating to a charger when the car heating the battery to 95F to accept fastest charging speed.

In case there was a question, I took a photo of the battery temperature on the dash immediately upon entry to the car. The battery temperature is pretty darn close to the point that the car typically targets with preconditioning to get a 280 kW peak charging session at a 350 kW EA station (for me).

I really wish that I could buy a testing device to read the data directly from the car's computers and data log it to an NVME drive for constant analysis.

 

[SergeyIndy]

The car tells you if the temp is ideal or not for fast charging. This is what this bracket on the right is for and 71F is short of being inside the bracket.

This is from the 2025 Taycan launch docs. The part that somehow Macan EV is missing (may be added later) is on the left side, which is "Max charging power prediction".

 

[SteveInKirkland]

The car tells you if the temp is ideal or not for fast charging. This is what this bracket on the right is for and 71F is short of being inside the bracket.

Yes, I'm aware.

"Scheduled Departures" is clearly raising the battery temperature for operational effectiveness of some sort and data from past experiments indicates the battery temperature (71F) is correlated with "best observed" charging performance. Hopefully, it is also correlated with other good driving performance and longevity outcomes.

Another good experiment will be to schedule departure charge to a maximum of 30'% or 40% or 50% capacity and then take the car immediately to a 350 kW charger. My bet is the charge curve looks pretty close to the max effective rates that I ever see in practice.

 

[SteveInKirkland]

The car tells you if the temp is ideal or not for fast charging. This is what this bracket on the right is for and 71F is short of being inside the bracket.

I saw that you edited your reply.

While I think of what is happening as preconditioning, it's more accurate to say that Scheduled Departures is bringing the battery temperature to align with best conditions for operational readiness. A by-product of that is that the battery is closer than a cold start to being at peak conditions to accept a charge.

 

[W1NGE]

There were some questions about what really happens when you set a planned departure time for the Macan EV and you have it plugged in for charging. This post is my experience from yesterday and today.

Yesterday at about 7 pm I plugged the Macan EV into a Level 2 AC charger in the USA (9.6kW). No departure times were set. The SoC at start was 63% the car was set to charge to a max of 80%. The car started to charge. There were no special considerations to attempt to charge the car between special hours. The car was sitting in a 66 F temperature controlled garage that maintained the temperature until the garage opened for the car to leave for the day.

A bit later, I set a departure time for 9:15 am and sent the changes to the car. The car's scheduled departure was set *not* to precondition the car's climate system. The SoC was 76%. The My Porsche app reported the car's charging status as Paused and the Level 2 charger reported 0 amps being delivered until much later in the morning.

At about 7:15 am, the car switched from Paused charging to charging at a non-peak rate (8 kW) The car finished charging prior to the planned departure and the battery temperature had been elevated to 71 F when I entered the car at 8:58 am and I left 17 minutes before the scheduled departure time.

On the 7th of February, I ran a similar test but, rather than adding a planned departure, I just let the car charge to 80%. It took max power (9.3 kW) from the wall throughout the charging session until it was finished and actually reported 81% SoC. When I left in the morning, no planned departure time set, the car's battery temperature was 64.

So ... observations:

(1) Planned departures do precondition the battery.
(2) The amps delivered to the car were not the peak possible. The car sipped power from the wall on its own schedule aligned with the departure time. It seemed to intentionally do this to raise the temperature of the battery.

I have screen shots and photos of the raw observations. If people are really interested in seeing the raw data, I can upload them. It just takes a bit of time. If you can think of another experiment to learn more, you're welcome to suggest it.

The preconditioning experienced here is nothing more than what naturally occurs when applying power to a battery (any) to charge it - it will naturally increase in temperature due to the chemical reaction that takes place. Analogous to charging your phone - it warms up but we don't refer to this as 'pre-conditioning'.

A 4C shift in temp is marginal at best and doesn't factor in the ambient temperature in general.

I took a 126 mile drive on Monday in a 4S Macan EV with the battery at 10C on start and reached 14C at then end (ambient 5.5C) - so 'cold' throughout. I then went to DC charge - set the stopover and the now preconditioned battery was 32C (which enabled 235kW charging), this is a pre-conditioned battery.

Nice observations but we need to be clear on what battery preconditioning is (or more importantly, what it isn't).

 

[SergeyIndy]

^ I agree 100% and very helpful to understand the difference.

The point of the experiment is to say that when departure time charging the battery gets warmer, which is more optimal for driving say 70F, vs. starting from colder ambient 50F.

Full preconditioning of the battery to 95F may be optimal for charging but may be too hot for driving.

 

[tonyadduci]

Assume no Level 1/2 charging at the home garage:
If I want to take it to a Level 2 charger and have the battery at 73 degrees F (optimal for faster charging), then I can simply activate the preconditioning the night before, and it will raise the temp of the battery to the ideal setpoint, correct? It doesn't have to be trickle charging on level 1/2 at home to precondition the battery, correct?

 

[tonyadduci]

Assume no Level 1/2 charging at the home garage:
If I want to take it to a Level 2 charger and have the battery at 73 degrees F (optimal for faster charging), then I can simply activate the preconditioning the night before, and it will raise the temp of the battery to the ideal setpoint, correct? It doesn't have to be trickle charging on level 1/2 at home to precondition the battery, correct?

 

[SteveInKirkland]

Assume no Level 1/2 charging at the home garage:
If I want to take it to a Level 2 charger and have the battery at 73 degrees F (optimal for faster charging), then I can simply activate the preconditioning the night before, and it will raise the temp of the battery to the ideal setpoint, correct? It doesn't have to be trickle charging on level 1/2 at home to precondition the battery, correct?

I don't know yet. It's on my list of experiments to run. I really wish there was an online resource, like a manual, to tell us.

 

[SteveInKirkland]

The preconditioning experienced here is nothing more than what naturally occurs when applying power to a battery (any) to charge it - it will naturally increase in temperature due to the chemical reaction that takes place. Analogous to charging your phone - it warms up but we don't refer to this as 'pre-conditioning'.

Let's be clear about what's happening here: we're socially constructing the language to tell new owners what is happening. In my case, I'm trying to answer my wife's questions. New owners, like me, don't have a document to tell us what the socially acceptable language is, so we're making it up given the lack of readily available information. Of course there are going to be negotiated changes to the social constructions.

A 4C shift in temp is marginal at best and doesn't factor in the ambient temperature in general.

In my experiment, where the outdoor temperature was in the mid 60's F and the indoor temperature was also controlled to in the mid-60's F with humidity reduced, the scheduled departure process added 4C to the temperature. The experiment wasn't done with the Macan in a hot environment or a cold environment. BUT we know from the observations that the charging procedure implemented by the software intentionally raised the temperature of the battery pack at least 4C under these conditions. If the battery temperature was 100 F, it might have cooled the pack. If the battery temperature was 0 C, it might have raised the temperature more. This is sort of the point -- we (new owners) don't know how the process works.

 

[Daniel]

@SergeyIndy , you wrote:
" Departure target charging is basically gently charging the battery in sipping cycles as you mention to get it to the intended target if there is more time than necessary to reach that target. This is to say that it will be running at peak if the time to target is short"

That was true with my Taycan, but not with my Macan.
Although the departure timer setting is acivated, approximatively 30 mn after the start of "preferred hours" charging begins at maximun available power , not respecting the scheduled departure time.

If this time is respected, it will only be by pure chance.
Maybe I am the only one in this case?

PS I am charging with the PMCC of my previous Taycan

 

[tonyadduci]

I think the logic in this preheating of the battery is flawed. There should be a button that says pre-heat battery and it just gets it up to temp at whatever cost and does that until it's at temp and if not driven after 15min, then turns off.

also, it could be preheat battery so that at xx:xx time it's at 73 degrees. I never know exactly what time I am going to leave I just know that I want the battery temp optimized by a specific time.

I also think if it's trickle charging at home that it should just keep the battery temp at an optimal temp or slightly below if it's the winter months? At least give us that option to do it.

 

[SergeyIndy]

@SergeyIndy , you wrote:
" Departure target charging is basically gently charging the battery in sipping cycles as you mention to get it to the intended target if there is more time than necessary to reach that target. This is to say that it will be running at peak if the time to target is short"

That was true with my Taycan, but not with my Macan.
Although the departure timer setting is acivated, approximatively 30 mn after the start of "preferred hours" charging begins at maximun available power , not respecting the scheduled departure time.

If this time is respected, it will only be by pure chance.
Maybe I am the only one in this case?

PS I am charging with the PMCC of my previous Taycan

Good correction as I was just speaking from Taycan experience assuming Macan EV will be doing the same.

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