Early 75/75D pack degradation

[smac]

The cars display of range may have nothing to do with the actual range and the actual battery capacity. That is, your battery could be seriously degraded and still display a "normal" range. My 90D when fully charged (done only a few times) shows a "rated" range of 275 miles or so. No way. Even when consuming only at the rated consumption of 324 wh/mi (difficult to do), my actual range is about 220 miles.

@PeterLucas

It might not even be showing us an accurate Wh/mi for all we know.

If I were a devious sort of guy and knew that people were looking at range in miles at 100% and the total amount of kWh drawn in the trip computer. Do you know what I would do? I'd mess with the definition of a Watt.

The logic would be that instead of W = Watt. W = Whateverwewant,

It would be much harder to notice / monitor degradation from an end users POV, if you then changed the Whateverwewant over time to track capacity.

The WhateverwewantH/mi would remain broadly consistent, so unless you were doing a full charge 100% to empty, you'd never know.

Maybe if you did do a full 100% to 0% range test periodically and compared it to miles driven (which hardly anyone would do), variations would be put down to experimental error (traffic, speed, weather, etc. etc.

The total Whateverwewant capacity would still tally with the trip computer, the range of Whateverwewants vs the typical Whateverwewants * capacity expressed in Whateverwewants would be the same.

Note, I'm not saying this is happening (and I don't believe it is otherwise Tesla would have done this from day one with the 85kWh pack!! If the W had stood for WhateverWeWant,, the trip computer from full to empty could have actually displayed 85kWh to match the badge on the back )

 

[sorka]

What makes you think that the actual range is anywhere near the cars display of range? My cars actual range (and battery capacity) are 15% to 20% less than the displayed range. 2016 90D.

That's too bad for you but I'm not certain what that has to do with this topic.

 

[sorka]

They all are. This is normal.

Yet another reason why you can’t determine actual battery capacity and health with this number.

Even with multiple ludicrous launches I'm easily getting rated range on my P85DL or do you mean this is normal for the 75D??

 

[Buster1]

Good question. The 3 Teslas I've ever driven (my 75D, a friend's 70D, and a loaner 90D) all had less projected range (as seen on the orange graph screens) vs what the BMS displayed next to the battery icon on the lower left dash screen.

When you say "rated range" where are you seeing that number? Rated range is the Tesla engineer's number based on 65 mph, no winds, no hills, 72 deg F, etc etc.

I think we (or maybe I am) mixing up some terms. But if you're doing multiple ludicrous launches, your projected range (in the orange graphs) will be much lower than the Tesla advertised rated range. It has to be.

 

[MP3Mike]

When you say "rated range" where are you seeing that number? Rated range is the Tesla engineer's number based on 65 mph, no winds, no hills, 72 deg F, etc etc.

I thought rated range was based on the EPA driving cycle.

 

[smac]

@Buster1
Are you talking about the energy graph on the main touchscreen?

(This is from an old version but will do)

If so my experience has been when the dotted projection line meets the solid "Rated/Ideal" line (depending on which you have selected in the settings), then the miles remaining on the dash match the projection.

Not being able to meet this average figure coded into the car (which from memory is 300Wh/mi, and based on the EPA test with no A/C, optimum weather etc.) is a separate issue from degradation.


Now for EU cars the plot thickens because our "Rated" setting is based on the laughable NEDC figures (which say a 75D should get 305 miles). It would be so incredibly difficult to hit in the real world, Tesla added "Typical". For most EU cars this "Typical" setting corresponds to a 325 Wh/mi. If you hit an average 325Wh/mi then real miles travelled decreases at the same rate as the range remaining in the dash goes down.



Time for a moan:

Because the Typical value is completely under Tesla's control, and not backed up by any official guidelines, they are free to set it at whatever they want, and it changes between models.

My UK pre-ap 60 had the stupid setting of 345Wh/mi. (although when brand new it shared the 325 typical of the 85 cars, it was messed about with via an OTA, and meant if I'd used the dash number the car as shipped would do over 200 miles, but post update could only do 180.... Now that would be some serious degradation!!!!)

Once the 345Wh/mi figure had been pushed to my car, it was trivial to beat. So I am probably in the unusual camp of having a car that "over performed" on real range vs displayed range..

While this does sound great, it had some nasty side effects: the Supercharger routing stuff was all off, it would insist at staying on a Supercharger too long, and silly warnings about slowing to get to my destination were very annoying. The funniest was when i was in sight of a Supercharger and the car going crazy at me to slow down despite 20 miles of remaining range! (Well actually 25 miles if looking at my last 5 mile average prediction )

Now why did Tesla do this to my car? My guess is for the UK market the 60 was enough range for most, but they wanted to up-sell cars. By messing with the figure it showed a bigger differential in the range displayed on the dash, and so increased the perceived value propositions, and encouraged people to spend more on the 85. (A bit like why they put an 85 on the trunk lid rather than the real 80 figure!) In doing so they made my car worse via an OTA, and despite me complaining to the Shambles Centre nothing was ever done to put it right.


Moral of the story, be very wary of using any of the information in the cars displays as proof positive of anything. Tesla can and have, messed around with them for reasons not to us as consumers benefit.

 

[Buster1]

So we have 3 terms we need to nail down.

Rated Range (RR)
Projected Range (PR)
Total Estimated Driving Distance (TEDD)

Rated Range yes I believe comes from Tesla engineers and the EPA. Solid line on the graph.
Projected Range is the dotted line and is a figure based on how you are currently driving, hills, winds, etc.
And from the Owners Manual, Total Estimated Driving Distance...that is the figure by the green battery icon on the dash. This is calculated by the BMS and can vary due to many things. (see
Battery Degradation; Sailing & Touching a Shore for more details)

I agree with you smac on that when they align, Rated = Projected...but that number (in my car) differs slightly from the BMS calculated TEDD

 

[dhanson865]

@wk057 I'm torn on this.

I'd really like to see some transparency, because like you I believe misrepresentation of products is wrong.

What scares me, and it has for a while, that if something like this comes to light it risks setting back all EV's, not just Tesla.

.....

I would hate for the press to have a field day and all EVs tarred with the same brush. If even one person who would buy a BMW EV decides not buy a BMW ICE, just because Tesla chose to put a pack out into the wild that wasn't ready, it would be a crying shame.

It's a tough one that's for sure, but I respect your decision which ever way you go.

Have you not seen the coverage of Nissan Leaf battery packs degrading in the heat since 2012 to now? Nissan shipped more of those packs than Tesla made Model S of all pack capacities. That means 75 and 90 packs are small portion of Tesla's Fleet and an even smaller portion of the overall EV fleet.

If painting the whole EV fleet with one brush would stop EV market growth Nissan's bad packs would have done that years ago. I do think you worry too much about the FUD factor.

 

[smac]

@Buster1 interesting in my car the TEDD always tallied (at least I never noticed it vary by more than 1 mile, even if I switched on or off range mode).

 

[smac]

If painting the whole EV fleet with one brush would stop EV market growth Nissan's bad packs would have done that years ago. I do think you worry too much about the FUD factor.

Maybe, I am worrying too much.

Though I don't get the impression people are seriously considering Leafs as ICE competitors, so any Leaf news gets ignored by people considering an ICE replacement.

 

[dhanson865]

Maybe, I am worrying too much.

Though I don't get the impression people are seriously considering Leafs as ICE competitors, so any Leaf news gets ignored by people considering an ICE replacement.

Hundreds of thousands of ICE have been replaced by the Leaf. You might be right that some ignored it but it sold because it really did replace an ICE vehicle for those that use it.

The fact that I got out of an ICE into an EV for sub $10K is why I consider it a good used car. The fact that someone else payed way more for it than I did is why I consider it a bad new car.

But price aside it has totally replaced all the gas I would have used in the last few years.

 

[smac]

@dhanson865 Don't get me wrong I actually think the Leaf is a very underrated car, esp. here in the UK where the thermal management is less important (at least from an overheating perspective). I even had Nissan come to my office and do a full presentation to all my staff, along with offering a salary sacrifice scheme should they want to have one.

As you rightly point out , all cars on the road are used vehicles, just some still belong to the first owner When those cars move out of first ownership, financially make them far more appealing.

What we are seeing here in the UK, was that Leaf (and Zoe's) took a horrible battering in residual values, being pretty much the worst depreciating car you could buy.

However now at the used prices, they are starting to generate quite a bit of interest, because people can buy one for cash and save a years fuel and congestion charges. Financially it's a bit of a no-brainer, even if they keep their ICE for odd trips. So if anything prices are strengthening. (One car whose used prices that seems to be gaining strongly is the Volt.)

Ultimately the goal is to replace as many ICE MILES as possible, and it's not just new cars that do that. New cars feed a pipeline and that pipeline trickles down.

So the message needs to be strong on degradation, that second owner vehicles still have a reasonable shelf life.

 

[dhanson865]

@dhanson865 Don't get me wrong I actually think the Leaf is a very underrated car, esp. here in the UK where the thermal management is less important (at least from an overheating perspective). I even had Nissan come to my office and do a full presentation to all my staff, along with offering a salary sacrifice scheme should they want to have one.

As you rightly point out , all cars on the road are used vehicles, just some still belong to the first owner When those cars move out of first ownership, financially make them far more appealing.

What we are seeing here in the UK, was that Leaf (and Zoe's) took a horrible battering in residual values, being pretty much the worst depreciating car you could buy.

However now at the used prices, they are starting to generate quite a bit of interest, because people can buy one for cash and save a years fuel and congestion charges. Financially it's a bit of a no-brainer, even if they keep their ICE for odd trips. So if anything prices are strengthening. (One car whose used prices that seems to be gaining strongly is the Volt.)

Ultimately the goal is to replace as many ICE MILES as possible, and it's not just new cars that do that. New cars feed a pipeline and that pipeline trickles down.

So the message needs to be strong on degradation, that second owner vehicles still have a reasonable shelf life.

True for the most part.

The key to why keeping Tesla honest isn't that the car has less of a shelf life. It's that the current owner experiences the loss of range and if they want to do something about it they then get the double whammy of selling a used car at a loss and buying a better one. But that reduced range car will still find a buyer.

So long as my car can do 50 miles in a charge I can keep it as my primary car. If someone takes a loss selling as the first owner, and someone else takes a loss as a second owner, and I end up with a Tesla Model S that can only do 150 miles on a charge it doesn't matter to me that it degraded but the two first owners paid the price because it did.

Anyone that paid Tesla for a new car or a CPO should hold Tesla to the higher standard as their finances will be directly affected sooner or later if they don't. And if Tesla is kept honest and doesn't let this go the Leaf route (poor residual value) then I eventually have to cave and buy a new or CPO Tesla and join the first or second owner club. That's the best case scenario for the brand in the long run. Pull in more new car buyers and make them happy, keep the turnover rate low and keep the used market hungry for more Teslas.

So I say wk057 should publish any data he can, let Tesla fix or not fix it, but for sure every owner and potential owner should know what they will or have gotten into.

 

[CSFTN]

@wk057 Keep up the good work, ignore the people who cannot accept the fact Tesla has missold/lied to them.

I love our 75D X, its the best car I have ever owned. But am under no illusion about how the real world works.

Without people like your self big business will think they can get away with anything......Lets not all forget just badly wrong it can all go if no one is there to keep a check on coporate greed.

Volkswagen emissions scandal - Wikipedia

Rather than make the assumption Tesla was intending to mislead anyone - as VW clearly was - how about considering that Tesla was entering uncharted territory, found some quirks, and worked them out going forward? And the battery is warranted, so if the degradation gets truly excessive, you get a new battery?

Myself, I put in an order for a P85D in January 2015, not intending to take delivery until May 2015, as the lease on previous car wasn't up until July. Gave me 2 months with 2 cars to work out any quirks I distinctly recall getting either a phone call or an email along the lines "we are bringing out a new battery chemistry. It will have about 3% more range but it is still experimental so we don't know how it will do in the long term. If it works out badly, we will replace it with an old-chemistry 85 Would you like to do that?" My answer was no - I will stick with the tried and true. From reading here, I knew the new chemistry had more (?) silicone in the (?) anode; that had been known for ~ 5 years to give more energy density, at the cost of earlier degradation. I distinctly recall someone posting - and I think it was either wk or FlasherZ - "I guess Tesla has worked out the silicone degradation problem. But we will see"

3 years later my car has 25,000 miles; my 100% charge went from 256 miles to 254 miles. But it almost doesn't matter. There is a supercharger about every 100 miles on every major interstate except ND, AK, NE Montana, and I-40 between Little Rock - OKC. And, as long as we are selling the car to a buyer who doesn't go out of their way to punish us for degradation, who cares? Anyone here sell their old car and get punished for degradation?

PS I base my numbers on the TEDD after re-calibrating by driving at highway speed down to <15% capacity and then recharging to >85% capacity I wish they wold give us a real measurement of capacity, with kWh or total pack voltage.

 

[gangzoom]

Rather than make the assumption Tesla was intending to mislead anyone - as VW clearly was - how about considering that Tesla was entering uncharted territory, found some quirks, and worked them out going forward?

You honestly belive Tesla aren't capable of falling into the same corporate arrogance as VW?

I persume you live on planet earth and interact with human beings......Last time i checked Tesla was also run by human beings, who as we all know never lie, always present the truth, and take full accountability of mistakes without any external pressures .

BS needs to be called BS, its as simple as that.

 

[Peter Lucas]

That's too bad for you but I'm not certain what that has to do with this topic.

The topic is battery degradation. Numerous folks here are reporting that their battery has little degradation, based on the vehicles display of range not changing much over time. Since the vehicles display of range, or remaining miles at the present state of charge, may not be anywhere close to accurate, this is very relevant to the topic. The battery may have degraded considerably, and the range display is simply failing to reveal it. Yes, that is too bad for me. But it may be too bad for many others as well. The huge database and analysis that Steinbuch did is all based on owners reports of the vehicles display of range. And since actual range is rarely reported, the data and charts are therefore meaningless. You can only know range if you compare actual miles driven to the portion of the battery that you have used. For example, if you start a trip with the battery at 80% charged, and finish the trip at 30% charged, you have used 50% of the batteries capacity. (I have checked. The SOC display is very linear.) So, if 50% of the battery takes you 110 miles, then your range for a fully charged battery is 220 miles. Even if the vehicle displayed a range of 270 miles when fully charged. Of course it is a better test if you go from 100% charged to nearly 0% charged. But I have checked. It is not much better. Extrapolating range this way requires allowances for excess speed, heavy use of heat or AC, etc. To avoid having to make those corrections or adjustments, use the cars display of energy used since last charged. That measurement should be fairly easy for the system to accurately measure. And I have found it to be at least consistent. If you take that number (energy used since last charged) and divide it by the change of state of charge (% charged when you started minus % charge when you finished), you get your battery capacity. For example, if your trip used 50% of your total capacity, and your energy used since last charge is, say 36 kwh, then 36/0.5 is 72 kwh. I have found this calculation to yield remarkably consistent values through a wide range of trip durations. Earlier tonight I finished a day that took the battery from 95% to 37%. That is 58% of a full charge. The kwh used during the day was 41.7 kwh. So: 41.7/0.58= 71.9 kwh. I get this same value, within about 1 or 2 percent, for any trip that uses more than 20% to 30% of the battery. A trip from 100% to 10% SOC yielded a similar number. During that trip, I made observations of SOC, energy used, and miles driven at several intervals. They plot out very linearly. The cars measurements of energy used and SOC appear to be very accurate throughout the full range of battery capacity (at least between 10% and 100% SOC). Allowing for a little headroom and floor room in the battery state of charge, my battery has 72/85=85% of if the capacity that it is supposed to have. And my real range is about 85% of the displayed 270 miles. If my actual range and battery capacity are 85% of rated, yours might be too.

 

[FlatSix911]

Paragraphs can be your friend here ...

The topic is battery degradation. Numerous folks here are reporting that their battery has little degradation, based on the vehicles display of range not changing much over time. Since the vehicles display of range, or remaining miles at the present state of charge, may not be anywhere close to accurate, this is very relevant to the topic. The battery may have degraded considerably, and the range display is simply failing to reveal it.

Yes, that is too bad for me. But it may be too bad for many others as well. The huge database and analysis that Steinbuch did is all based on owners reports of the vehicles display of range. And since actual range is rarely reported, the data and charts are therefore meaningless. You can only know range if you compare actual miles driven to the portion of the battery that you have used.

For example, if you start a trip with the battery at 80% charged, and finish the trip at 30% charged, you have used 50% of the batteries capacity. (I have checked. The SOC display is very linear.) So, if 50% of the battery takes you 110 miles, then your range for a fully charged battery is 220 miles. Even if the vehicle displayed a range of 270 miles when fully charged. Of course it is a better test if you go from 100% charged to nearly 0% charged. But I have checked. It is not much better.

Extrapolating range this way requires allowances for excess speed, heavy use of heat or AC, etc. To avoid having to make those corrections or adjustments, use the cars display of energy used since last charged. That measurement should be fairly easy for the system to accurately measure. And I have found it to be at least consistent. If you take that number (energy used since last charged) and divide it by the change of state of charge (% charged when you started minus % charge when you finished), you get your battery capacity.

For example, if your trip used 50% of your total capacity, and your energy used since last charge is, say 36 kwh, then 36/0.5 is 72 kwh. I have found this calculation to yield remarkably consistent values through a wide range of trip durations. Earlier tonight I finished a day that took the battery from 95% to 37%. That is 58% of a full charge. The kwh used during the day was 41.7 kwh. So: 41.7/0.58= 71.9 kwh. I get this same value, within about 1 or 2 percent, for any trip that uses more than 20% to 30% of the battery.

A trip from 100% to 10% SOC yielded a similar number. During that trip, I made observations of SOC, energy used, and miles driven at several intervals. They plot out very linearly. The cars measurements of energy used and SOC appear to be very accurate throughout the full range of battery capacity (at least between 10% and 100% SOC). Allowing for a little headroom and floor room in the battery state of charge, my battery has 72/85=85% of if the capacity that it is supposed to have. And my real range is about 85% of the displayed 270 miles. If my actual range and battery capacity are 85% of rated, yours might be too.

 

[Alokin]

I have an 85 that was delivered to me in Perth, Western Australia in February 2015.
I have been reading the battery life data and find it interesting.

Tesla has not yet installed ANY Superchargers in Western Australia but the RACWA has taken the initiate and installed about 8 charging units in the South-West of the state.

I have two chargers one at work and one at home.

Currently my milage is just over 112,000km (close to 70,000 miles.

For the first couple of weeks my battery would charge to about 401km 249 miles.
Lately I have been seeing 377

 

[Alokin]

I have an s 85 that is 3 years old this February and that has travelled nearly 113,000km.
Tesla has not seen fit to support Tesla drivers in Perth, Western Australia with any Tesla Superchargers so charging is somewhat more haphazard that say in California ; or anywhere in the USA come to that.
I charge at night-time off-peak rates at home and from a mains/Solar Power mixture at work.
Car has twin chargers.

I nearly always charge my car to the maximum possible as I never know what distance I may have to travel in any day and easily accessible charging points are not reliable.
When new, a full battery showed 401km.
This deteriorated over the years to a recent worst case of 377km.
Strangely, in the last couple of days I have seen 380km and 381km.
No idea why this would happen but it will be interesting to see which direction the battery capacity will move in the future.

Because we have no Tesla Superchargers, and because of the fact I need to keep my battery as close to maximum (even though I receive regular advice that I should not do so) due to the daily distances that may have to be covered, if I see an accelerating loss of battery capacity I will be expecting Tesla to be responsible for any remedial action required as they did no keep their promise of "free power" from Tesla Superchargers.

 

[JRP3]

if I see an accelerating loss of battery capacity I will be expecting Tesla to be responsible for any remedial action required as they did no keep their promise of "free power" from Tesla Superchargers.

Good luck with that one. You can get all the free charging you want from superchargers, you just have to get to one. Unless Tesla told you in writing that they would be installing SC's near you in a specified time period I don't think you have a leg to stand on.