Does regen change battery SoC %?

[Stu Kan]

I was driving down from Mt Hood (Oregon, USA) toward Portland on hwy26 where there is a lengthy opportunity for regen. I counted 24 miles added to the range estimate number. The state of charge % didn't increase, however (of course, it didn't decrease either...). In past trips short and long, I don't remember ever seeing the SoC % increase but I'm not sure I thought to look to even notice. I would think if that many estimated range miles increase is calculated that there should be some percentage increase going back into the battery? Has anyone else seen there SoC % increase through regen only?

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[Jasper4S]

The displayed SoC is calculated with margins. It does not flip from 84 to 83 when SoC is going from 83.51 to 83.49. This would cause a lot of flickering. And it also works the other way around when charging: if you set a target at 90% SoC, charging doesn’t stop when SoC is 89.5%. These margins make it so that if regen would change the SoC, it would almost need 1.5% battery before the SoC will show it. And that translates to 1.4 kWh with the Performance Battery Plus. And that makes it very unlikely you’ll ever notice it, maybe only if you are driving 250 km/h, braking at full power, and a lot of energy is being recovered.

Edit: my calculation was for j1.1, I see yours is j1.2. For yours it would mean you need to regen 1,65kWh given your battery is bigger. So even less chance you’ll ever see it

 

[Stu Kan]

The displayed SoC is calculated with margins. It does not flip from 84 to 83 when SoC is going from 83.51 to 83.49. This would cause a lot of flickering. And it also works the other way around when charging: if you set a target at 90% SoC, charging doesn’t stop when SoC is 89.5%. These margins make it so that if regen would change the SoC, it would almost need 1.5% battery before the SoC will show it. And that translates to 1.4 kWh with the Performance Battery Plus. And that makes it very unlikely you’ll ever notice it, maybe only if you are driving 250 km/h, braking at full power, and a lot of energy is being recovered.

Edit: my calculation was for j1.1, I see yours is j1.2. For yours it would mean you need to regen 1,65kWh given your battery is bigger. So even less chance you’ll ever see it

Makes sense--thx.

 

[Daniel]

Yes , the SOC display can change with regen.
As said @Jasper4S , the displayed SoC is calculated with margins but if the descent is step and more than 500 m, the displayed SOC will change.
For my J1 Taycan the gain was about 1% for 300 m of descent.

Here is a screen shot of the regen energy after a 550 m descent at low speed (because of corners, winter and snow) , even with low temperature.
Unfortunately, I didn't take a photo of the SOC before the descent, but the display had increased.
The calculation shows a gain of 2 kWh.

A note: my Macan no longer displays negative energy consumption, only zero consumption.
Furthermore, it doesn't take regen into account when calculating energy consumption for a trip.
I don't know if this is the case with the J2 Taycan.

 

[chun]

Yes , the SOC display can change with regen.
As said @Jasper4S , the displayed SoC is calculated with margins but if the descent is step and more than 500 m, the displayed SOC will change.
For my J1 Taycan the gain was about 1% for 300 m of descent.

Here is a screen shot of the regen energy after a 550 m descent at low speed (because of corners, winter and snow) , even with low temperature.
Unfortunately, I didn't take a photo of the SOC before the descent, but the display had increased.
The calculation shows a gain of 2 kWh.

A note: my Macan no longer displays negative energy consumption, only zero consumption.
Furthermore, it doesn't take regen into account when calculating energy consumption for a trip.
I don't know if this is the case with the J2 Taycan.

Macan EV has a different hardware and software stack, so probably handles things differently. Taycan J1.1 and j1.2 run same software and hardware stack, only j1.2 has updated software.

 

[Jasper4S]

Macan EV has a different hardware and software stack, so probably handles things differently. Taycan J1.1 and j1.2 run same software and hardware stack, only j1.2 has updated software.

The difference coupd be as simple as a single if-statement. If consumption < 0 => show 0.

@Daniel pretty could example 2kwh in 550m is nice. Quicker than AC charging

 

[Sly_North]

I was driving down from Mt Hood (Oregon, USA) toward Portland on hwy26 where there is a lengthy opportunity for regen. [...] I don't remember ever seeing the SoC % increase but I'm not sure I thought to look to even notice. [...] Has anyone else seen there SoC % increase through regen only?

Yes: going from the top of Furkapass (altitude 2400m) to a service station (alt about 500m), I get about +5% SOC on screen. -2000m over 52km.

 

[Stu Kan]

Yes , the SOC display can change with regen.
As said @Jasper4S , the displayed SoC is calculated with margins but if the descent is step and more than 500 m, the displayed SOC will change.
For my J1 Taycan the gain was about 1% for 300 m of descent.

Here is a screen shot of the regen energy after a 550 m descent at low speed (because of corners, winter and snow) , even with low temperature.
Unfortunately, I didn't take a photo of the SOC before the descent, but the display had increased.
The calculation shows a gain of 2 kWh.

A note: my Macan no longer displays negative energy consumption, only zero consumption.
Furthermore, it doesn't take regen into account when calculating energy consumption for a trip.
I don't know if this is the case with the J2 Taycan.

Terrific! I'll need to look out for the right descent to see it myself. I would guess the elevation change on the route I drove would be at least 500meters and steep/rapid enough. But I just might have missed the SoC% increase too...

 

[Stu Kan]

Terrific! I'll need to look out for the right descent to see it myself. I would guess the elevation change on the route I drove would be at least 500meters and steep/rapid enough. But I just might have missed the SoC% increase too...

an update on this while still fresh in my mind: Yesterday I drove down Hwy 74 in S. California and made sure to keep track of %SoC: it went from 35% to 39%; and miles range estimate 119 to 165. The elevation drop was over 4,000 feet in approximately 15 miles.

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