Supercharger charging at half the speed it was the previous day

[TANGO SUKKA]

I was at a supercharger the other night getting about 350mph worth of charging. I went back to the exact same stall today (with nobody there) and was only getting 150mph. I tried a different stall and got the exact same thing.

What would cause the charge rate to get cut in half? There were no other cars charging at the place.

 

[P85_DA]

Depends on current state of charge in car if high than charge tapers ..also not sure if u are at urban charger or regular super charger but that will also have variation

 

[TANGO SUKKA]

Depends on current state of charge in car if high than charge tapers ..also not sure if u are at urban charger or regular super charger but that will also have variation

It was the exact same supercharger I used the night before and both times I had about 230 miles available out of 310.

 

[P85_DA]

It was the exact same supercharger I used the night before and both times I had about 230 miles available out of 310.

At high SOC charge rate tapers ..based on ur numbers u were at 75% SOC ..so that is correct behavior from what u seen in car

 

[SSedan]

I doubt you saw 350mph with 230 in the battery. Maybe at the start of that session but not once at that high a level.

Superchargers charge slower the more energy is in the battery, a constantly slowing curve.

 

[ewoodrick]

It was the exact same supercharger I used the night before and both times I had about 230 miles available out of 310.

A charge doesn't stay at full current from empty to full. It's highest around 20-50% and then starts tapering off after that. You are definitely at the taper.

For most other EVs, many DC Fast chargers only allow 30-45 minutes charging. After that, the Level 2 (Destination equivalent chargers) provide just as fast of a charge as the DC Fast charger. That's why you often see charging specified as " to 80% in 30 minutes"

 

[TexasEV]

It's best to compare by reporting kW, not mph, as kW is an instantaneous reading but mph is an average over the session. When you report the kW you are getting, also give the percent state of charge of the battery at that time.

 

[Mike_F]

Same thing happened to me today at Petaluma. I have a P3D+ that has free supercharging and today was the first time I used it. I was expecting 110 - 120 kW (SOC was about 30%) at least at the get go. I noticed the charging rate started as usual but then abruptly stopped at exactly 60 kW, went to another stall, same thing. Petaluma is a 20 stall set up and only 2 other cars there (not sharing on either). Has anyone with Performance free supercharging been able to charge above 60 kW? Is TM limiting free supercharging for P3 to tier 1?

 

[TexasEV]

Has anyone with Performance free supercharging been able to charge above 60 kW? Is TM limiting free supercharging for P3 to tier 1?

Over the years there have been various conspiracy theories about Tesla intentionally “throttling” supercharger speeds for one reason or another, such as proximity to where you live, etc. None have been borne out, all were related to problems with the supercharger itself. It wouldn’t make any sense to do that as slowing charging would just make superchargers more crowded. Anyway “tier 1” rates are only for states where Tesla isn’t allowed to charge by the kWh delivered.

 

[Mike_F]

Over the years there have been various conspiracy theories about Tesla intentionally “throttling” supercharger speeds for one reason or another, such as proximity to where you live, etc. None have been borne out, all were related to problems with the supercharger itself. It wouldn’t make any sense to do that as slowing charging would just make superchargers more crowded. Anyway “tier 1” rates are only for states where Tesla isn’t allowed to charge by the kWh delivered.

The reason I bring up tier 1 is that the cutoff for tier 1 is 60 kw and the charging rate initial increase ended abruptly at 60 kw each time. Coincidence? I am going to charge at another SC in a few days. Be interesting if it repeats. Agree it makes no sense to throttle.

 

[eprosenx]

It was the exact same supercharger I used the night before and both times I had about 230 miles available out of 310.

What were temperatures outside both days and how warm/cold might your battery have been?

Starting from a different battery temp may have impact as well.

I can’t speak to the conspiracy theories, etc, though I do wonder if Tesla might throttle the superchargers at times based on grid load or power costs. Like they don’t want to pay big demand fees and they know they are in their peak demand window.

 

[R1Fast]

Seeing different amperage/charge rates each visit is normal.

SCs also distribute (and will throttle) based on the # of paired connections. A 10 charger station will likely charge a single EV at a higher amperage vs the same station with 18 EVs connected at 9 stalls.

Example

 

[forkee]

Has anyone with Performance free supercharging been able to charge above 60 kW? Is TM limiting free supercharging for P3 to tier 1?

Yes to your first question. No, to limiting question.

This was at the urban supercharger in Downey, CA. 8/12 stalls full.

 

[Mike_F]

Yes to your first question. No, to limiting question.

View attachment 340035

This was at the urban supercharger in Downey, CA. 8/12 stalls full.

Your display looks a bit off. Why does battery SOC at top right corner show "82%" whereas your mileage SOC shows 194 miles which is closer to 65%? 72 kW is awfully low for a SOC of 65%. You may want to have someone look at it.

 

[Big Earl]

Your display looks a bit off. Why does battery SOC at top right corner show "82%" whereas your mileage SOC shows 194 miles which is closer to 65%? 72 kW is awfully low for a SOC of 65%. You may want to have someone look at it.

I guess you don't know that urban Superchargers are limited to 72 kW per stall, as opposed to the shared configuration of non-urban Superchargers that top out at 120 kW per vehicle.

Since the image is a screen shot from his phone, the 82% is his phone's battery level.

 

[forkee]

Your display looks a bit off. Why does battery SOC at top right corner show "82%" whereas your mileage SOC shows 194 miles which is closer to 65%? 72 kW is awfully low for a SOC of 65%. You may want to have someone look at it.

I guess you don't know that urban Superchargers are limited to 72 kW per stall, as opposed to the shared configuration of non-urban Superchargers that top out at 120 kW per vehicle.

Since the image is a screen shot from his phone, the 82% is his phone's battery level.

Right, sorry. That's my phone charge.

 

[Jedi2155]

Unless people are in a serious hurry (road trip or somewhere else), a lower charge rate is probably better for your battery.....

 

[_TTT_]

I frequently supercharge my S and 3 at an urban supercharger nearby. I'm very familiar with the charge speeds at all battery charge levels. However in the past week sometime, something interesting has occurred.

It's behaving like my car thinks it's a full speed supercharger and is directing the stall to send power levels accordingly. For example, when my 3's battery is about half full (more or less), I would expect around 100kW of power from a full speed supercharger and 72kW at an urban one. Instead, I was getting 50kW. As the battery approached 60% charge, I would expect around 80kW from a full speed supercharger but I was getting 40kW instead. This trend continued where I was getting pretty much half of what I would expect from a normal supercharger.

Does anyone know how the car directs the charger to select the power level? Does the car tell it to use a percent of its available power or does it tell it a specific power value? Would be interesting if my car thought the charger was capable of 140kW and was telling it to use a percent based on that number. Would explain why everything was halved since this was an urban charger only capable of 72kW.

I tried 5 different stalls so this wasn't a cabling issue...they all behaved the same. I'll try again today and see if the behavior is any different. Maybe I'll try my S as well.

 

[Big Earl]

I frequently supercharge my S and 3 at an urban supercharger nearby. I'm very familiar with the charge speeds at all battery charge levels. However in the past week sometime, something interesting has occurred.

It's behaving like my car thinks it's a full speed supercharger and is directing the stall to send power levels accordingly. For example, when my 3's battery is about half full (more or less), I would expect around 100kW of power from a full speed supercharger and 72kW at an urban one. Instead, I was getting 50kW. As the battery approached 60% charge, I would expect around 80kW from a full speed supercharger but I was getting 40kW instead. This trend continued where I was getting pretty much half of what I would expect from a normal supercharger.

Does anyone know how the car directs the charger to select the power level? Does the car tell it to use a percent of its available power or does it tell it a specific power value? Would be interesting if my car thought the charger was capable of 140kW and was telling it to use a percent based on that number. Would explain why everything was halved since this was an urban charger only capable of 72kW.

I tried 5 different stalls so this wasn't a cabling issue...they all behaved the same. I'll try again today and see if the behavior is any different. Maybe I'll try my S as well.

Did you try rebooting the screen? I've had that solve slow Supercharging behavior in the past.

 

[_TTT_]

Yes, I unplugged, rebooted the screen, did a manual power down and power back up. Nothing helped. I'll get some more info today with both cars....