Supercharger getting mostly Chademo speeds

[Booga]

Have we had two people charge their Tesla's at the same location with a similar SoC? If they are both throttled to these low rates that the OP (Mattzilla) is getting, then it's likely an output issue. If it's limited to one car, then it has to do more with that specific car. If it's the former (supercharger constraint), I wonder if the next version of superchargers will improve this with improved cooling for the AC->DC conversion hardware and/or cabling that can withstand it better.

 

[Mattzilla]

Have we had two people charge their Tesla's at the same location with a similar SoC? If they are both throttled to these low rates that the OP (Mattzilla) is getting, then it's likely an output issue. If it's limited to one car, then it has to do more with that specific car. If it's the former (supercharger constraint), I wonder if the next version of superchargers will improve this with improved cooling for the AC->DC conversion hardware and/or cabling that can withstand it better.

I actually tried this at a Supercharger in Oregon, I believe Sandy, earlier this year. A fellow owner was able to get 114kW speeds on a charger that only gave me 81kW. We both had around 10-15% SoC. He had an older Model S. I told Tesla about this and it didn't change their verdict. They are claiming my car is being throttled but have refused to acknowledge that some cars can charge faster than others due to battery chemistry. This has been discovered and posted here, but Tesla, as far as I know, has never acknowledged it.

I've decided to just accept that my car cannot achieve 120kW, and it will never achieve 80% in 40 minutes, even though Tesla never said a word about these limitations to me while selling me the car (and they've still never admitted that my car was never capable of 120kW because it is a 75D).

 

[Galve2000]

They are claiming my car is being throttled but have refused to acknowledge that some cars can charge faster than others due to battery chemistry.

I know you mentioned this upthread but how many times would you say you visited a SC in the life of your car? Have you done any ChAdeMo charging as well?

 

[Mattzilla]

I know you mentioned this upthread but how many times would you say you visited a SC in the life of your car? Have you done any ChAdeMo charging as well?

I've Chademo charged about 5 times. Definitely less than 100 DCFC sessions total. Car is barely over a year old. Most of my SCing was on long road trips, otherwise I charge exclusively at home or on an AC unit at work.

 

[Booga]

I actually tried this at a Supercharger in Oregon, I believe Sandy, earlier this year. A fellow owner was able to get 114kW speeds on a charger that only gave me 81kW. We both had around 10-15% SoC. He had an older Model S. I told Tesla about this and it didn't change their verdict. They are claiming my car is being throttled but have refused to acknowledge that some cars can charge faster than others due to battery chemistry. This has been discovered and posted here, but Tesla, as far as I know, has never acknowledged it.

I've decided to just accept that my car cannot achieve 120kW, and it will never achieve 80% in 40 minutes, even though Tesla never said a word about these limitations to me while selling me the car (and they've still never admitted that my car was never capable of 120kW because it is a 75D).

That's pretty weak on Tesla's part and disappointing. Some of the service issues and lack of openness make me think twice about my upcoming purchase. Despite that, I tell myself that the positives (autopilot, primarily) outweigh it. I hope I'm not disappointed on delivery of my future car.

 

[Mattzilla]

That's pretty weak on Tesla's part and disappointing. Some of the service issues and lack of openness make me think twice about my upcoming purchase. Despite that, I tell myself that the positives (autopilot, primarily) outweigh it. I hope I'm not disappointed on delivery of my future car.

I really don't think you will be, man. This car has completely changed my life, and I mean that. I'm not being hyperbolic. I arrive at destinations refreshed and ready to engage. I love that I get to drive to work each day. It's such an amazing car in so many ways. I think the few downsides are all the more maddening when you have such an amazing product like this, because you realize what Tesla is capable of. Anyway, looking back, I don't regret buying Tesla at all. I'm a bit annoyed on a few fronts, but none of them would put me back in any of my previous cars. Not even close.

 

[stopcrazypp]

Ok so I did some more testing over the last few days.

Today I rolled in at the Aberdeen supercharger with 1%. I wanted to see how close I could get to Tesla's claim of 80% in 40 minutes per their website.

No other Teslas at the station, car well warmed up, and outside temps in the 70s. Relatively new Supercharger. Cables were not warm. I moved to three different stalls during charging and deducted the time it took to move and hook up/ramp up again from my measurements.

It took me about 60 minutes to hit 80%.

Last I spoke to Tesla staff about this issue, the engineer informed me "this should only add about 5 minutes maximum to your Supercharging sessions." I guess that's the PR line they've been instructed to repeat, regardless of its validity.

15-20 shortfall is significant. I was just happy this time I was able to charge around 80kW for a good chunk of the session, which I haven't been able to experience for any length of time since early last fall.

Isn't the spec from 10 to 80% in 40 minutes? How long did that take?

 

[Galve2000]

I've Chademo charged about 5 times. Definitely less than 100 total DCFC sessions total. Car is barely over a year old. Most of my SCing was on long road trips, otherwise I charge exclusively at home or on an AC unit at work.

I am dismayed that there would be such a laughably low upper limit for supercharging. I am lucky enough to rarely have to SC these days but I had hoped to keep my 85D until the wheels fell off. Now I am rethinking this.

I am also worried that excessive Level 2 charging too might be detrimental in some way.

 

[Mattzilla]

Isn't the spec from 10 to 80% in 40 minutes? How long did that take?

Tesla has removed the information from their website, but some of the information is saved on the Wiki page, which states "80% charge in 40 minutes." I see no stipulation about starting at 10%. That would mean actually charging 70% in 40 minutes.

Tesla Supercharger - Wikipedia

 

[nwdiver]

There's a good change some, most or possibly all of these issues are due to local grid constraints. Electricity isn't magic... there are physical laws it must obey too. We know that the SC cabinets use the same modules as our cars so we know they're current limited not power limited. If you plug into 208v at 40A you get 8.3kW. If you're lucky enough to find a HPWC wired to 277v you get 11kW. But those are nominal voltages. I've seen 240 get pulled down to ~200v by high demand in a residential area on a hot day.

A lot of these issues may not be resolved until the local grid is upgraded or Tesla adds a battery pack to the station AND that pack is keeping up with demand....

 

[Mattzilla]

There's a good change some, most or possibly all of these issues are due to local grid constraints. Electricity isn't magic... there are physical laws it must obey too. We know that the SC cabinets use the same modules as our cars so we know they're current limited not power limited. If you plug into 208v at 40A you get 8.3kW. If you're lucky enough to find a HPWC wired to 277v you get 11kW. But those are nominal voltages. I've seen 240 get pulled down to ~200v by high demand in a residential area on a hot day.

A lot of these issues may not be resolved until the local grid is upgraded or Tesla adds a battery pack to the station AND that pack is keeping up with demand....

What about charging, seeing my max rate, then moving so another Tesla can charge, and seeing their max rate much higher than mine? I'm doubtful it's the chargers in at least some of these cases. There is something going on with some cars.

 

[stopcrazypp]

Tesla has removed the information from their website, but some of the information is saved on the Wiki page, which states "80% charge in 40 minutes." I see no stipulation about starting at 10%. That would mean actually charging 70% in 40 minutes.

Tesla Supercharger - Wikipedia

Hmm, that wikipedia page says the reference was retrieved from the supercharger site on 10/23/2014. I look at the wayback machine and see no reference to 80% in 40 minutes.
I only see "up to 50% battery capacity in about 20 minutes".
Supercharger | Tesla Motors

 

[stopcrazypp]

I am dismayed that there would be such a laughably low upper limit for supercharging. I am lucky enough to rarely have to SC these days but I had hoped to keep my 85D until the wheels fell off. Now I am rethinking this.

I am also worried that excessive Level 2 charging too might be detrimental in some way.

The algorithm is likely predictive. Meaning it is based on kWh DC charged per unit time, not on a hard cut off of DC charges.

I give an example how this might work in a different thread:

If it is a predictive/dynamic algorithm, it would presume this is the standard use case, and that for the rest of the miles/life the usage will be similar. So it'll limit max speed so that under the predicted usage, it'll be able to keep degradation similar.

In this case the OP use about 300 DCFC per year (I should note the evidence is point to it counting kWh, not sessions, but let's just use this for illustrative purposes). Over 8 years it'll predict it will see 2400 DCFC. It'll adjust the max charging speed to reach its degradation goals in 8 years.

Then another person who will do the same 300 DCFC, but take 4 years to do it (75 per year). In 8 years, it'll only see 600 DCFC. It'll take 32 years to reach 2400 DCFC. So to reach similar degradation in 8 years, it might not even have to limit the speed (or as much).

You can replace years with miles or total kWh, but the idea is similar.

People seem to be assuming something like: 300 DCFC = limited, but that actually makes less sense. A dynamic way would maximize the utility out of the battery.

 

[Mattzilla]

Hmm, that wikipedia page says the reference was retrieved from the supercharger site on 10/23/2014. I look at the wayback machine and see no reference to 80% in 40 minutes.
I only see "up to 50% battery capacity in about 20 minutes".
Supercharger | Tesla Motors

Strange. Here is an Electrek article stating 80% in 40 minutes, but I don't see a reference to the figure:

Tesla quietly upgraded its Superchargers for faster charging, now capable of 145 kW

And another article stating the same thing:

Imagine Charging Tesla Motors, Inc.'s Model S in Just 5 Minutes -- The Motley Fool

 

[TexasEV]

Hmm, that wikipedia page says the reference was retrieved from the supercharger site on 10/23/2014. I look at the wayback machine and see no reference to 80% in 40 minutes.
I only see "up to 50% battery capacity in about 20 minutes".
Supercharger | Tesla Motors

For several years the supercharger page had a graph showing up to 80% in 40 minutes. The fine print said it was for 85s. This was when there were 60s and 85s.

 

[Mattzilla]

Hmm, that wikipedia page says the reference was retrieved from the supercharger site on 10/23/2014. I look at the wayback machine and see no reference to 80% in 40 minutes.
I only see "up to 50% battery capacity in about 20 minutes".
Supercharger | Tesla Motors

Also, looking at the first case example in this thread, which is a more common representation of my Supercharging experience since last fall, a 50% charge took 40 minutes. Again, even with Tesla's statement about "only adding 5 minutes," that's still a 15-20 minute shortfall.

 

[stopcrazypp]

Strange. Here is an Electrek article stating 80% in 40 minutes, but I don't see a reference to the figure:

Tesla quietly upgraded its Superchargers for faster charging, now capable of 145 kW

And another article stating the same thing:

Imagine Charging Tesla Motors, Inc.'s Model S in Just 5 Minutes -- The Motley Fool

I did some googling. From here, in June 2016 it referenced 10-80% in 40 minutes
Supercharger 54% in 37 minutes | Tesla

From wayback machine, it references 90kWh S specifically:
"Supercharger Charging Profile
Based on 90 kWh Model S

Charging from 10% to 80% is quick and typically provides ample range to travel between most Superchargers. Charging from 80% to 100% doubles the charge time because the car must reduce current to top off cells. Actual charge times may vary."

The diagram doesn't show up correctly but the text is (note print under the diagram does say it's 10% to 80% and it has disclaimer that actual charge times may vary) :
40 minutes 80%
75 minutes 100%
Supercharger | Tesla Motors

 

[stopcrazypp]

Also, looking at the first case example in this thread, which is a more common representation of my Supercharging experience since last fall, a 50% charge took 40 minutes. Again, even with Tesla's statement about "only adding 5 minutes," that's still a 15-20 minute shortfall.

The advertised specs are always going to be for peak speeds (and from what I can find they use a specific battery type in the example). In the real world, there's a lot more factors that can lower the speeds.

 

[Booga]

The advertised specs are always going to be for peak speeds (and from what I can find they use a specific battery type in the example). In the real world, there's a lot more factors that can lower the speeds.

Sure, but in the case of this thread, it seems that he's systematically below what the car should be capable of and it deviates from the population of cars.

 

[gabeincal]

The max rate on my S75 is 94-96kW. Have never seen anything higher than that.