What was your maximum charge rate at a supercharger?

[Fiver]

I know the M3 can take it, but most Gen2SC' are 120KW max, and you pretty much took it all - no? That I haven't seen. I think this is the record high for m/hr charging.

I'm not sure what you mean. I've gotten 119kW many times in my 2013 P85+. The difference is I don't hold that rate very long, only from very low state of charge to about 35% whereas the Model 3 will take that rate for much much longer up to a higher percentage before it starts to taper down as the battery fills.

/edit If you're talking about the miles per hour charge rate, that's kind of a placebo number that doesn't really matter. You'll never get the amount of miles it says you will, it just says if somehow you could take 119kW for the duration of your charge (you won't) you would get that many miles. It all depends on your average wh/mile and every car/driver is different.

 

[Marsnaut]

Interesting... I have a snapshot to prove it but I'm a little too lazy to post right now.

I was at 178 miles and charging at 481 mi/hr but at 92kw!! This was at the Binghamton Supercharger with no other car charging in any of the stalls.

 

[Fiver]

Interesting... I have a snapshot to prove it but I'm a little too lazy to post right now.

I was at 178 miles and charging at 481 mi/hr but at 92kw!! This was at the Binghamton Supercharger with no other car charging in any of the stalls.

Yea the miles per hour charging figure is essentially useless. The real focus should be on the kW delivered and for how long can it hold that rate.
If you could really get 481 miles of range per hour charging you could go from 0-100% in like 35 minutes, and we all know that's not true.

 

[Zoomit]

I guess it needs repeating that the miles of range per hours indication is an average over the charge cycle. Showing a 481mph with an instantaneous 92 kW is reasonable if it’s just starting to taper at just over 50% SoC.

 

[amitmishra4]

I know the M3 can take it, but most Gen2SC' are 120KW max, and you pretty much took it all - no? That I haven't seen. I think this is the record high for m/hr charging.

It was definitely a Gen2 (120kw) and I have charged at other superchargers before a couple times and didn’t get close to this but I think there are a flurry of factors that dictate how fast it charges - SOC, number of cars sharing the stations, outside temperature, battery pack temperature, charge limit etc. so I may have gotten lucky with the right combination. I was hoping to hit 500 but it leveled off at 490, not sure if I would have gotten a higher rate with a lower SOC. This was in Milford, CT at the Connecticut post mall charging station and there was only one other Model X charging in a spot on the other corner.

 

[Fiver]

Showing a 481mph with an instantaneous 92 kW is reasonable if it’s just starting to taper at just over 50% SoC.

Except no one is getting 481 miles per hour of actual range added. It's not possible. The way it's displayed is really disingenuous. It's like if you weighed yourself standing on a scale while descending in an elevator... You could SAY you weigh less they you really do, but it only holds true while the elevator is descending, and elevators can't descend forever.

I wish the miles per hour of range added wasn't based on the unsustainable instantaneous power delivery and could factor in the inevitable taper and give you an accurate number.

 

[North75]

Except no one is getting 481 miles per hour of actual range added. It's not possible. The way it's displayed is really disingenuous. It's like if you weighed yourself standing on a scale while descending in an elevator... You could SAY you weigh less they you really do, but it only holds true while the elevator is descending, and elevators can't descend forever.

I wish the miles per hour of range added wasn't based on the unsustainable instantaneous power delivery and could factor in the inevitable taper and give you an accurate number.

The miles per hour number is accurate up to the current point in time. If you charge from 10% to 50% at 120 kW you will have added mileage at a rate of ~500 mi/hr. Obviously as the charge tapers the average will steadily drop.
I charged from 25% to 90% and wound up averaging around 325 mi/hr which still pretty impressive. I was getting a full 120kW below the taper start.

 

[Zoomit]

Except no one is getting 481 miles per hour of actual range added.

Don’t confuse 481 miles...in one hour, with the average charge rate of 481mph. Quantities are different than rates. As noted above, these average rates seem accurate.

 

[amitmishra4]

Seems to be confusion around the concept of instantaneous rate of change vs an average rate of charge - I believe the display in the Tesla shows you a rate-based measurement for that point in time so it is the former. I equate it to be just like your speedometer reading mi/hr. You could be on a highway driving 80 mi/hr for 30 mins and then on local roads for 40 mi/hr for 30 mins and your average for the one hour trip will be 60 mi/hr, but that does not change the fact that for the point in time you were on a highway your rate of speed was 80 mi/hr. You are likely charging at 480-490 mi/hr although for a shorter duration than an hour perhaps because the instantaneous rate of charge tapers with SOC and time. The average depends on how long I leave it plugged in and what unit of time I measure against. If I am charging at 480 mi/hr and leave it plugged in for 1 min, my average rate of charge for 1 min is 480 mi/hr. I think it is useful to measure the rate of my charging at any instant to ensure I am getting the expected performance, just like it is important to measure my speed at every instant to predict how long it will take to get to my destination.

 

[Fiver]

I guess you're right. That said, it just doesn't feel right to me to express the charge rate in that manner. "I'm doing 75mph on the highway..." people get what you mean, it's your speed at that moment, even if it doesn't reflect your real speed averaged for the trip. For traveling that works, but saying I'm charging at 450 miles an hour to me implies you are gaining range way faster then you really are. For charging your miles gained per hour shouldn't really be gauged by the rate "at that moment".

"I'm gaining range at 400mph from this charger!"

"Great, we can leave in 5 minutes then?"

"Well, no, that won't be enough..."

"But you just said you're charging at 400mph... 5 minutes should provide the 30 miles of range for us to get to where we are going...."

 

[swaltner]

Usain Bolt can run the 100 yard dash at 27.8 miles per hour. That doesn’t mean he can run a marathon (26.2 miles) in less than an hour, which would be half the time of the world record.

 

[amitmishra4]

I guess you're right. That said, it just doesn't feel right to me to express the charge rate in that manner. "I'm doing 75mph on the highway..." people get what you mean, it's your speed at that moment, even if it doesn't reflect your real speed averaged for the trip. For traveling that works, but saying I'm charging at 450 miles an hour to me implies you are gaining range way faster then you really are. For charging your miles gained per hour shouldn't really be gauged by the rate "at that moment".

"I'm gaining range at 400mph from this charger!"

"Great, we can leave in 5 minutes then?"

"Well, no, that won't be enough..."

"But you just said you're charging at 400mph... 5 minutes should provide the 30 miles of range for us to get to where we are going...."

Yes - I see your point and it is valid from a consumers point of view. Theoretically, a better way is to express it in a smaller more realistic unit of time, like minutes, since the rate of charge fluctuates in minutes. So instead of 480 mi/hr, it would have been 8 mi/min. I think the reason that is not the way they decided to go is that most people that charge at home or anywhere less than a supercharger would see decimals of 0.5 or below and there is no other unit of time in between.

Maybe the Gen 3 chargers will be so quick that we wont need to worry about hours at all.

 

[Fiver]

Yes - I see your point and it is valid from a consumers point of view. Theoretically, a better way is to express it in a smaller more realistic unit of time, like minutes, since the rate of charge fluctuates in minutes. So instead of 480 mi/hr, it would have been 8 mi/min. I think the reason that is not the way they decided to go is that most people that charge at home or anywhere less than a supercharger would see decimals of 0.5 or below and there is no other unit of time in between.

Maybe the Gen 3 chargers will be so quick that we wont need to worry about hours at all.

Yea, a better analogy to supercharging is like when you are going on a trip to a place 75 miles away. The first few minutes of the trip you're on the interstate, doing 75 miles an hour. Doesn't mean you're getting to the destination in 1 hour. After a few minutes on the highway you get off onto a smaller, slower road, and then another smaller, even slower road. Towards the end of the trip you're on some one lane class IV dirt road in the middle of the woods barely driving faster then you can walk.

 

[ohmman]

Yea, a better analogy to supercharging is like when you are going on a trip to a place 75 miles away. The first few minutes of the trip you're on the interstate, doing 75 miles an hour. Doesn't mean you're getting to the destination in 1 hour. After a few minutes on the highway you get off onto a smaller, slower road, and then another smaller, even slower road. Towards the end of the trip you're on some one lane class IV dirt road in the middle of the woods barely driving faster then you can walk.

Hey, I've taken this trip before!

 

[tga]

I believe the display in the Tesla shows you a rate-based measurement for that point in time so it is the former

To be clear, the kW displayed is an instantaneous measurement of current charge power. Mi/hr is average over the entire charging session, which is why it's pretty useless.

 

[PaulusdB]

To be clear, the kW displayed is an instantaneous measurement of current charge power. Mi/hr is average over the entire charging session, which is why it's pretty useless.

Probably the message above needs repeating every other page of this thread.

Whatever reason the software people had for displaying that time averaged charging speed (bigger numbers are better?), it works out that users get under the impression of charging at a much higher rate than they in fact are. This leads to longer charge sessions on Supercharger stations.

 

[ohmman]

This leads to longer charge sessions on Supercharger stations.

I'm guessing you mean "longer than expected" charge sessions. Because clearly it doesn't slow things down.

However, I don't necessarily agree with that conclusion either. The car gives you a reasonable estimate of time remaining. "30 minutes to continue on your trip" or "40 minutes remaining." There's an instantaneous power readout. There is rated range and/or SOC reflected in percentage. Each of these items are tools to choose from, and while the miles per hour of charge is clearly not everyone's favorite, I don't see how one could look at all of the metrics and still conclude that they're going to be done sooner than the estimate.

 

[PaulusdB]

I'm guessing you mean "longer than expected" charge sessions. Because clearly it doesn't slow things down.

However, I don't necessarily agree with that conclusion either. The car gives you a reasonable estimate of time remaining. "30 minutes to continue on your trip" or "40 minutes remaining." There's an instantaneous power readout. There is rated range and/or SOC reflected in percentage. Each of these items are tools to choose from, and while the miles per hour of charge is clearly not everyone's favorite, I don't see how one could look at all of the metrics and still conclude that they're going to be done sooner than the estimate.

Of course the informed user doesn’t get confused. I should’ve explained more, about why I guess users overstay during their SuperCharger sessions.
I think there is a common misconception of the usefulness of the remaining time spent at the SuperCharger. Although the correct, low kW is displayed, it feels like worthwhile for them to get those last 15 minutes of charging upto more than 90% as the speed still seems hundreds of miles/km per hour. Where in reality only a few more miles/km get added and the stall could just as well be vacated.

 

[ohmman]

Of course the informed user doesn’t get confused. I should’ve explained more, about why I guess users overstay during their SuperCharger sessions.
I think there is a common misconception of the usefulness of the remaining time spent at the SuperCharger. Although the correct, low kW is displayed, it feels like worthwhile for them to get those last 15 minutes of charging upto more than 90% as the speed still seems hundreds of miles/km per hour. Where in reality only a few more miles/km get added and the stall could just as well be vacated.

I hadn't thought about that aspect. I wonder how often this really happens. I'm not others, so it's hard for me to imagine, but I agree that at the end of the session some people might be misled by this particular statistic. Not for long, though, as they should see very few rated miles appearing as they wait.

There is value, in my opinion, to having the miles of range per hour of charging statistic be session-based. When you're about to unplug, it's nice to know your average rate of charge for the entire session. I'd probably settle for something more like kWh/h (aka, average kW) for the session, as it may be less misleading to certain owners.

 

[Fiver]

I hadn't thought about that aspect. I wonder how often this really happens. I'm not others, so it's hard for me to imagine, but I agree that at the end of the session some people might be misled by this particular statistic. Not for long, though, as they should see very few rated miles appearing as they wait.

There is value, in my opinion, to having the miles of range per hour of charging statistic be session-based. When you're about to unplug, it's nice to know your average rate of charge for the entire session. I'd probably settle for something more like kWh/h (aka, average kW) for the session, as it may be less misleading to certain owners.

Really the display should just list: Miles added, current kW charge rate, & estimated time remaining to either continue on trip or reach desired charge percentage. The miles per hour as others have stated just causes confusion as it's wildly inaccurate over the duration of a charging session.