If you fast charge, Tesla will permanently throttle charging

[JRP3]

Here is some news for you. There are a number of variables that permanently degrade your battery.

Battery cycling (aka number of miles), calendar (aka age). And here is another shocking news for you - some battery packs degrade more than others. So if you have two packs that have cycled 1000 times in 3 years, they both may or may not have exactly the same range and the same charging rate.

Amusing that you seem to feel you have more information about lithium ion behavior than I do.

Were you told about any of those things when you bought the car? Did someone give you the degradation curve and charts and probability analysis ? All you were told - which you knew already - and the range and the charging times are good to go when new, and batteries degrade over time and miles.

This is no different from that.

The difference which you seem to be ignoring is that some people specifically asked Tesla if Supercharging would cause problems and were told it would not. I believe that is an error on Tesla's part which should be corrected.

 

[jdw]

Inflammatory or not, it's definitely not accurate. Something more like "Frequent DC charging may reduce future maximum fast charge rates" would be more accurate.

Agree - "throttling" is the wrong word. You wouldn't use that word to describe the difference in initial charge rate between a 60kWh and 90kWh battery. Initial charging rate is determined by pack size and version, temperature and now by a calculated battery condition based on the number of DC fast charges.

The net result is using a different charging taper for different packs, temperatures and battery conditions. In many cases the total charging time is similar as the peak charging rate is reduced but the average charging rate is the same or not much lower.

 

[AnxietyRanger]

Here is a practical suggestion that perhaps we as a community and even Tesla as a company could adopt as a recommendation to owners.

Similar to battery charging level being recommended at 90% (or 80% or 50%) and 100% recommended only for when absolutely needed... since it is better for the battery...

Perhaps this could be the recommendation for DC charging as well. Recommend AC charging for all times when Supercharging or CHAdeMO charging is not absolutely mandatory... since AC charging is better for the battery.

These are very practical, simple tools to communicate to people. It does not have to be broken down any further than that. The guy installing CHADEMO at home would know to use it for emergencies only.

I would have had absolutely no complaints had this been taught like the 90% rule was...

 

[TexasEV]

Amusing that you seem to feel you have more information about lithium ion behavior than I do.
The difference which you seem to be ignoring is that some people specifically asked Tesla if Supercharging would cause problems and were told it would not. I believe that is an error on Tesla's part which should be corrected.

I believe that trying to explain the possibility of a trivial increase in supercharging time that affects less than 1% of owners will cause more confusion than it corrects.

 

[AnxietyRanger]

I believe that trying to explain the possibility of a trivial increase in supercharging time that affects less than 1% of owners will cause more confusion than it corrects.

How about my "best practice" suggestion above?

 

[Az_Rael]

I may have missed this, since this thread blew up over night, but Electrek did release an article. Looks like they didn't get additional info, just what JonMC posted

Tesla explains why it limits Supercharging speed after high numbers of DC charges

 

[TexasEV]

Here is a practical suggestion that perhaps we as a community and even Tesla as a company could adopt as a recommendation to owners.

Similar to battery charging level being recommended at 90% (or 80% or 50%) and 100% recommended only for when absolutely needed... since it is better for the battery...

Perhaps this could be the recommendation for DC charging as well. Recommend AC charging for all times when Supercharging or CHAdeMO charging is not absolutely mandatory... since AC charging is better for the battery.

These are very practical, simple tools to communicate to people. It does not have to be broken down any further than that. The guy installing CHADEMO at home would know to use it for emergencies only.

I would have had absolutely no complaints had this been taught like the 90% rule was...

What an overreaction! That's worse than the problem you're trying to solve. That would cause everyone to change behavior unnecessarily, and kill use of EVs. You want to change how everyone is told to charge in order to avoid a trivial increase in supercharging time that less than 1% of owners experience? I think you've lost all sense of proportion.

 

[Electroman]

I believe that trying to explain the possibility of a trivial increase in supercharging time that affects less than 1% of owners will cause more confusion than it corrects.

Exactly.

How about my "best practice" suggestion above?

Sometimes the issue is so trivial, it is not worth adding it to set of best practices, as it confuses and dilutes some of the more critical messages that we need to take home.

One of the best practices that was hammered over and over - charge at home, and use SCs for trips. i think that adequately covers this specific use case.

If you love to count pennies, you will be counting pennies throughout your life

 

[Electricfan]

Inflammatory or not, it's definitely not accurate. Something more like "Frequent DC charging may reduce future maximum fast charge rates" would be more accurate.

What is the difference between "permanently throttle charging" and "reduce future maximum fast charge rates"? LOL! To me the only difference is one is plain-spoken truth, the other sounds like marketing material Tesla would write.

But, if Tesla would put your statement verbatim on their website I'd be satisfied by that. Its not as good as "permanently throttle charging" but its close enough.

 

[jdw]

I may have missed this, since this thread blew up over night, but Electrek did release an article. Looks like they didn't get additional info, just what JonMC posted

Tesla explains why it limits Supercharging speed after high numbers of DC charges

And in the comments of this article we have exactly the problem of trying to communicate an issue like this to the public,

Most are ranting on about "the counter" not being visible and "resale value" and "by God, I paid for this vehicle, how dare they" and are treating this as a serious limitation rather than a relatively minor protective/preventative measure being taken after hundreds of fast charges whose only effect is (possibly) a charge taking a few extra minutes to complete in some situations.

How do you explain, especially to a non-owner, that the initial charge rate is only one of many factors that affect charging time. How do you explain the charge taper of different battery capacities and versions ...

sigh ....

 

[thefortunes]

The difference which you seem to be ignoring is that some people specifically asked Tesla if Supercharging would cause problems and were told it would not. I believe that is an error on Tesla's part which should be corrected.

2 points:
1) I'm not sure we have the evidence related to the impact of SuC (yet?). OP and others with reduced charge rates use CHAdeMO. This may or may not be a factor.
2) We also don't know if this is new information that Tesla has discovered, thus the information that was provided was accurate at the time.

I guess a 3rd - I remember back in 2012-2013 when I was evaluating buying a Model S (I ended up buying a Roadster instead and have subsequently bought an S for my wife) that I was told exactly what Anxiety is requesting - that slow charging is better for the battery (of course we were also told then that SuC was only for road trips ).

 

[Electricfan]

What an overreaction! That's worse than the problem you're trying to solve. That would cause everyone to change behavior unnecessarily, and kill use of EVs. You want to change how everyone is told to charge in order to avoid a trivial increase in supercharging time that less than 1% of owners experience? I think you've lost all sense of proportion.

Let me see if I understand you - you're against Tesla even admitting on their website that DC fast charging will cause them to reduce charging rates after a time period or certain number of charges?

 

[AlMc]

My bad: I have spent more time reading through this thread than I will probably spend with a decrease in charge rate at Superchargers for the rest of my life.

Thanks Jon McNeil for some comment on the matter.

I am far from the smartest person on this thread/these forums but no matter what I was told in written or verbal comments/messages from Tesla I just thought it logical that over time fast charging would have some effect on the rate of charging and battery life.

edit: The OP has indicated that he would rather have more degradation in his battery life and faster DC charge rates. I respect his frame of reference. Mine is the opposite, especially if we are talking 3-10% more time spent at a Chademo or SC station.

 

[Electroman]

And in the comments of this article we have exactly the problem of trying to communicate an issue like this to the public,

The pattern is very similar in any thread. it is a small section - one or two - that keep repeating over and over again, flaming the flames and watching replies roll by.

 

[El Boricua]

Oh.. the free loaders?

We are not free loaders, we are Tesla supporters that live in apartments. Even when we do not have to pay for the energy used while SC, because our car price included it (it is not free), it is an inconvenience to have to charge out of our homes. However, I decided to have the inconvenience in order to support Elon and his vision, and have the best car in the world. But that decision was made also based on the information provided in my multiple visits to the Tesla center in Freemont, before making the purchase. The Tesla representatives there never mentioned that supercharging only will have a penalty. On the contrary, they mentioned the SC as the alternative for apartment dwellers. I made my purchase based on the information provided, and even when I may not change my support for Tesla if there is a penalty for supercharging, I demand to know the actual facts from the horse's mouth.

 

[Electroman]

My bad: I have spent more time reading through this thread than I will probably spend with a decrease in charge rate at Superchargers for the rest of my life.

Thanks Jon McNeil for some comment on the matter.

I am far from the smartest person on this thread/these forums but no matter what I was told in written or verbal comments/messages from Tesla I just thought it logical that over time fast charging would have some effect on the rate of charging and battery life.

Because you have common sense and you use it.

 

[Electricfan]

And in the comments of this article we have exactly the problem of trying to communicate an issue like this to the public,

Most are ranting on about "the counter" not being visible and "resale value" and "by God, I paid for this vehicle, how dare they" and are treating this as a serious limitation rather than a relatively minor protective/preventative measure being taken after hundreds of fast charges whose only effect is (possibly) a charge taking a few extra minutes to complete in some situations.

How do you explain, especially to a non-owner, that the initial charge rate is only one of many factors that affect charging time. How do you explain the charge taper of different battery capacities and versions ...

sigh ....

The OP's car only has 30k miles on it, and now it won't charge nearly as fast as it did when it was new. I'd be a lot more upset about it than he/she is. The answer to your question is simple honesty. Something on the website like "The Tesla battery pack is intended to be charged at low power rates except when travelling long trips. Exclusive use of DC Fast charging will result in a reduced charging rate enforced by Tesla superchargers to protect the life of the battery."

 

[Matias]

And that is exactly the issue here. "Some cases" turns out to be less than 1%.

It's unfortunate that this thread has such an inflammatory title (and likely is misleading a number of people). It makes it sounds as if Tesla is arbitrarily throttling people who fast charge, rather than slowing the charge rate slightly (like by 5 min) to protect the battery.

Well... you can only blame Tesla. If they'd proactively told this feature, this thread would be much smaller and with a different title. It really surprises me, that once again Tesla thought, that users would not notice.

I can list at least four cases, where Tesla told the truth only after customers had started to demand explanations;

1) Missing torque sleep in the first D models
2) Missing HPs in the P85Ds
3) Launchgate limiter
4) Charging limiter

Everyone of those caused unnecessary bad will, which would have been much smaller, IF Tesla had proactively told about these things.

 

[JRP3]

I believe that trying to explain the possibility of a trivial increase in supercharging time that affects less than 1% of owners will cause more confusion than it corrects.

Here's the problem, Tesla seems to have plans to increase the number of urban superchargers to service those who have no or limited access to AC charging. If they intend to have people charge almost exclusively from high power DC sources they need to disclose that it may have increased negative effects on the pack over time. Specifically, when asked about the effects of high power DC charging, they cannot say it will have no negative effect as they seem to have done in the past.

 

[SageBrush]

What ...
What is ...

Are you ... ?

Down the hole, Alice.

JRP3 is demonstrating the problem I was mentioning earlier regarding people who say "if only Tesla had been transparent ..." There is no limit to details that can be shared. And for a company like Tesla that is continually tweaking stuff, the demand is not even practical. So either you accept a certain amount of variance between cars as the price of continuous improvement and thank Tesla for keeping the differences minor except for the outlier, or you choose Toyota.