If you fast charge, Tesla will permanently throttle charging

[jerry33]

I suspect the reason Tesla isn't more forthcoming on this is because there are a lot of variables that can affect the rate of charge, battery degradation, etc. The result is that almost anything they could put in writing can be wrong under some circumstances (not that anyone here in TMC would nit-pick any statement made by Tesla). To expect people to actually read and understand all the possible scenarios and apply them in a sensible manner would be way too optimistic. Plug in when possible, charge within the daily range unless you need the extra miles, and don't hog the Superchargers is about as much as you can expect people to understand. If you're really lucky, they will even follow them most of the time.

 

[AnxietyRanger]

I suspect the reason Tesla isn't more forthcoming on this is because there are a lot of variables that can affect the rate of charge, battery degradation, etc. The result is that almost anything they could put in writing can be wrong under some circumstances (not that anyone here in TMC would nit-pick any statement made by Tesla). To expect people to actually read and understand all the possible scenarios and apply them in a sensible manner would be way too optimistic. Plug in when possible, charge within the daily range unless you need the extra miles, and don't hog the Superchargers is about as much as you can expect people to understand. If you're really lucky, they will even follow them most of the time.

To clarify, do you think not mentioning it at all in their materials is the way to go?

Not even in CHAdeMO adapter manual, for example?

The ethics get very tricky very fast if hiding this seems like a preferable option...

 

[jerry33]

Obviously you have to follow your own sense of what's important, but I'd suggest not worrying about it and using the CHAdeMO chargers anyway. Max charge rate is a very brief portion of any charge session, if it's ever reached at all, so even if max charge rate is reduced, the actual time increase is fairly small. As Jon said in his post, you might see a five minute increase in your SC session, which is relatively minor compared to the 30 minutes to an hour you'd be charging at a SC anyway. But again, do what's right for you and your peace of mind.

Thirty minutes to an hour seems very long based on my experience. (Exceptions: cold weather, or going off the SC network). Except for lunch breaks and overnight stops, you're only charging enough to get to the next SC plus a small amount of reserve.

 

[T34ME]

Tesla customer at time of purchase: "When I charge my car will supercharging harm the pack in any way?" Tesla: "No, supercharge as much as you want"

See the problem?

Maybe Tesla's knowledge base has changed since the time of your theoretical new car purchase. Maybe Tesla still doesn't know the impact of Chademo, SuperCharger, or whatever, if any, since we are all in new territory here with newer and newer battery technology. How can they say anything different than what JonMc said, if they still aren't certain about the issue? To me, preventing battery degradation is more important than saving 5 minutes.

Tesla has a tiger by the tail with 400K+ reservations for the TM3 and there IS going to be some "slip ups". Do I expect them to notify me of that inevitable potential? No, I fully expect it logically. They are a very young company and they are making some mistakes and I believe learning from their mistakes. I feel like we are similar to the pioneers trekking into the unknown in covered wagons. I am willing to be one of those pioneers. I believe in Tesla's concept and embrace it even though I may suffer some inconvenience or lack of knowledge for the benefit of future generations of EV cars and owners.

I am good with JonMc's response. It hasn't changed anything for me, I still want my TM3, possible warts and all!

 

[jerry33]

To clarify, do you think not mentioning it at all in their materials is the way to go?

Not even in CHAdeMO adapter manual, for example?

The ethics get very tricky very fast if hiding this seems like a preferable option...

I think if it was me, I'd just say charging rates can vary because battery life is at or near the top of the list.

 

[AnxietyRanger]

I am good with JonMc's response.

@JonMc's post parahprased into Tesla's website and manuals would be a good start. So far there is nothing on this, not even on the Supercharger FAQ where slowdown is specifically discussed.

I still want my TM3, possible warts and all!

It seems possible this does not affect Model 3 at all, but Model S/X only, since Model 3 is expected to have the new cells (and Model S/X not for 6+? months). So certainly waiting for Model 3 may be wise from this perspective.

Tesla battery researcher unveils new chemistry to increase lifecycle at high voltage

 

[AnxietyRanger]

I think if it was me, I'd just say charging rates can vary because battery life is at or near the top of the list.

OK, thanks for clarifying. (To me it gets tricky when you have to be frugal with the full truth. It implies a problem with being honest - and that's a problem.)

 

[MS16]

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.

5) We never discount (except when we do)

6) 85 = 85kWh

7) Safest Car in America! (unless you use IIHS test results)

 

[EV-lutioin]

Helpful battery vocabulary for this discussion:

http://web.mit.edu/evt/summary_battery_specifications.pdf

 

[AlMc]

The problem with trying to define every single situation that could affect charging rates and battery degradation is starting to look like Bill Clinton parsing the word 'is'.

*NOT* to bring politics in but to give an example of no matter what Tesla puts in writing or the verbiage that their staff uses you can not possibly satisfy everyone in every situation about every aspect of the battery.

 

[MS16]

You realize that the impact to you, IF this were to happen, would be an extra 5 min at a supercharger. Some on this thread are making it sound catastrophic. It's not.

Please continue to use and enjoy your car

Yeah, what's an extra 16% of time wasted waiting on your throttled Supercharging session anyway? You had to waste 20 minutes in line just to get on open charger anyway.

It's not like time is a precious resource or anything.

 

[T34ME]

@JonMc's post parahprased into Tesla's website and manuals would be a good start. So far there is nothing on this, not even on the Supercharger FAQ where slowdown is specifically discussed.

I dunno, maybe because he just posted that response this morning?

 

[Skipdd]

Because he saved ~ $600 by sitting at ChadDemo chargers for 150 hours, and he did it for the money. This is the same guy who is now up in arms over the ~ 3 - 5 minutes he now loses on the occasions he uses a SuperCharger.

Since no rational person who makes more than half of US minimum wage in his locale would use ChaDemo this way, his behavior is perverse.

per·verse
pərˈvərs/
adjective

1. (of a person or their actions) showing a deliberate and obstinate desire to behave in a way that is unreasonable or unacceptable, often in spite of the consequences.
   • contrary to the accepted or expected standard or practice.
     "in two general elections the outcome was quite perverse"
     synonyms: illogical, irrational, unreasonable, wrong, wrong-headed
     "a verdict that is manifestly perverse"

Nice try - your definition is not the most common one. From Merriam Webster - the first definition is "wrong or different in a way that others feel is strange or offensive". That's why when you google perverse you see lots of examples of behaviors that people find unsavory. That is not the case here at all. We all can have different opinions of the OP's choice, but don't try and brand it as something most would find offensive.

 

[smac]

7) Safest Car in America! (unless you use IIHS test results)

It was safest car in the world. Only after they started shipping did they realize AEB was a prerequisite for 5 star award and hastily rushed out AP1 with just that feature enabled.

Frankly since then I take all the PR with a pinch of salt and view it as spin.

 

[ohmman]

This was not disclosed beforehand and now the figure is 5 minutes. Could it be progressive? Could they find out later they need to make it 15 minutes or something?

They aren't 'making it' some number of minutes. It's a limit on peak charge rate. You know better and I'm sure you can represent that knowledge more clearly if you choose.

As I posted earlier, it's the current worst case scenario. There is no way to do worse than that time aside from Tesla lowering the cap or changing the taper curve dramatically. Speculation on that happening is just that - speculation.

 

[krouebi]

Hi,

thanks for your reactions - I just find it kinda funny to pay quite a lot of money for an accessory that if used will augment charging times.

At least we're lucky not to have dished out 10K for the Ludicrous upgrade - how many "shots" do you get for the 10K?

And of course you're right, it IS a relatively minor issue for me - but not for everyone, including the OT.

I can indeed live with an increase in charging time. But still, it would have been nice to be warned about this side effect of fast charging.

 

[AnxietyRanger]

I dunno, maybe because he just posted that response this morning?

According to the service center contacts reported, Tesla has known about this for weeks or months. Their silence on this seems intentional.

I do hope they change that now. Maybe next week then?

 

[anticitizen13.7]

7) Safest Car in America! (unless you use IIHS test results)

In terms of real-world data...

The 2013-2015 casualty rates reported by IIHS are highly favorable towards the Model S:

http://www.iihs.org/iihs/topics/insurance-loss-information

In the large luxury category, Model S scored 39 in personal injury payouts regardless of fault, making it 61% better than average in terms of accident injury. A MB E-class had higher payouts, scoring about 80, or only 20% better than average. The BMW 5 was slightly less safe than the Benz, scoring about 75, or 25% better than average.

The chief problem with the Model S is that it caused more harm to occupants of OTHER cars, rating 104, or 4% worse than average.

 

[Canuck]

The peak charging rate possible in a lithium-ion cell will slightly decline after a very large number of high-rate charging sessions. This is due to physical and chemical changes inside of the cells.

Then shouldn't we expect this to happen to all vehicles "after a very large number of high-rate charging sessions"? Yet that doesn't seem to be the case.

Our fast-charge control technology is designed to keep the battery safe and to preserve the maximum amount of cell capacity (range capability) in all conditions. To maintain safety and retain maximum range, we need to slow down the charge rate when the cells are too cold, when the state of charge is nearly full, and also when the conditions of the cell change gradually with age and usage.

Isn't this just a general statement that applies to all lithuim ion batteries? I don't see it as answering the question as to what exactly causes a vehicle to join the 1%'ers.

Tesla is not slowing down charge rates to discourage frequent Supercharging – quite the opposite. We encourage our customers to use the Supercharger network at their discretion

This a strange way of expressing that policy unless it changed with idle fees and new vehicles having to pay after 400 kWh/year.

And also @Canuck 's theory was incorrect.

Permanently restricting DC charging speeds sounds a lot like throttling to me.

It does appear I was wrong about the reason -- but not the result. And it still bothers me we don't know the exact reason and thus we can't avoid the trigger. I do appreciate @JonMc posting here to attempt to clear things up, but we really need to know exactly what caused the trigger to be pulled on the 1%'ers.

You realize that the impact to you, IF this were to happen, would be an extra 5 min at a supercharger. Some on this thread are making it sound catastrophic. It's not.

If it happens to my car it will be a slight annoyance. I certainly won't lose any sleep over it. I drive to my cabin most weekends, and supercharge both ways, and a few extra minutes spent isn't a big deal, but it would sure be nice to know the throttling trigger so I could try to avoid it.

I've added 6 people to my ignore list thanks to this thread. The difference in quality of users back in 2008 when I joined and now is extreme.

And in the White House.

 

[ODE90D]

I agree there is a limit to how much Tesla can communicate to the public, but I really think they should explain why the batteries with the new chemistry are experiencing reduced SuC charge peak while the "old" generation are not affected.

Had I known about this back in December 2015 I would have chosen a 85D instead as I mainly Supercharge from 10%-40% to make my daily 350 km commute and hate the idea of having to spend more and more time at the SuC ( currently my peak is down to 95 kW after 100k km)