Tesla's 85 kWh rating needs an asterisk (up to 81 kWh, with up to ~77 kWh usable)

[cynix]

yeah too bad the only global standard is to state the spec capacity. you could mandate all cars state the usable capacity at 65mph (since usable capacity is speed dependent for more reasons than one) but wouldnt it be simpler to simple state the range at 65mph and then customers to use that value when shopping?

Sure, I think it's fine if they advertised different models purely based on range, and never mentioned capacity. At least that'll make the different models comparable.

However they made a decision to advertise capacity, yet they chose to rate different models differently, making it impossible to make a valid comparison. That is the problem.

 

[WarpedOne]

After 4 years still NO ONE has tried to replicate EPA range.

People obsess with estimated range, talk about "lost" range in that estimated number, fight over usable kWh of their pack etc but NO ONE has even tried to come up with EPA range of a car with some miles on odometer.

Why is that so?
Is it really that hard to repeat the EPA cycle and MEASURE the actual range of the car to compare with stated EPA number?

That is one single most important metric of an EV (i.e. range represented in comparable number) and still no-one has actually measured the EPA range of a used car and compared that number with a published one?

If people would go through this with new cars and then repeat the procedure after some usage we would get some really important answers:
- are published specs of new cars correct or people really don't get what they payed for
- how good is estimated range calculation
- what does real battery degradation look like and how is effected by age, usage, etc

It is dead easy to always show same estimated range like there is no degradation. It is also dead easy to fake little degradation by only dropping estimated range by a bit over time and usage. Until people go and repeat the EPA cycle with a used car all talk about battery capacity (new, real, theoretical,..) is just hot air.

Who will be the first to repeat EPA with their own car?

 

[No2DinosaurFuel]

I think the main take away from this thread is the 60s and the 70s are underrated. The 85 is uoverrated. 90 is ? Until someone do the test and verify.

Seems to me like i might be opting for the 70 becuase it is the best deal now that i know the specs.

For those who thinks the overrating doesnt affect sales, i can guarantee it does. So tesla just have lost an 85 sale. We all know the 70s are lower margins cars. Again more people will need to confirm with more data, but if what the op say is true, i definitely will change my mind about getting the 70 or 85.

 

[schonelucht]

But as the battery pack is sold in a car you drive just as the hard drive is sold in a computer (usually) that has a file system and an OS on it with overhead yet Apple and others still advertise 1TB for example.

Interesting side note : Apple is in the early stages of being sued by the largest consumer organisation in Belgium on account of their phones not having the advertised capacity available for the user to use.

 

[CO2CLEAN]

Interesting side note : Apple is in the early stages of being sued by the largest consumer organisation in Belgium on account of their phones not having the advertised capacity available for the user to use.

Offtopic: but they are just the start, the plan is to create a precedent to be used to other companies as well.

I'm more curious about new information regarding the battery and how well it performs, rather than a discussion about the "ethics" of advertising a capacity that may not equal real life usable capacity.

 

[WarpedOne]

I think the main take away from this thread is the 60s and the 70s are underrated. The 85 is uoverrated. 90 is ? Until someone do the test and verif

One only needs to look at the front page to see which car is over/underrated.
All the info needed is and was there from day one.
Current situation:
- 70D: 240 epa miles for $76.200 : $317.50/mile
- 90D: 288 epa miles for $89.200 : $309.72/mile

90D is a better value (or under-rated) compared with 70D and vice-versa.

 

[bridaus]

They could be designated by EPA range, or they could be called Model S (formerly 60, now 70), Model S R (R=range, formerly 85 now 90) and Model S P. For example. Or they could be the Model S Azure, Comanche and Apache for all I care.

Annoyed. And under this scenario I have even less of an idea of what I am buying. This discussion is largely empty air without knowledge of what the nameplate capacity of the cells are and the specific draw.

 

[Johan]

Annoyed. And under this scenario I have even less of an idea of what I am buying. This discussion is largely empty air without knowledge of what the nameplate capacity of the cells are and the specific draw.

Meaningless names is the lesser of two evils when compared with misleading names.

 

[deonb]

You could boot it via a Live USB, for example. The point is that it's easily doable without any hardware modifications to the computer itself.

I remember in the old 20 MB MFM days there was a program we used that emulated a Hard Drive as a tape, so you can get a full 20'000'000 bytes on it without having any file system overhead. Well, of course you still had filename & length overhead, but you didn't have the cluster size overhead.



PS: This statement (which I've seen echo'd a few times), isn't quite accurate:

To use a computer analogy, Dell buys a 1 TB drive from, say, Seagate. That's actually 930 or so gigabytes since computers actually use 1024 instead of 1000 per kb.

Hard drive & tape manufacturers have never stated numbers in KiB / MiB / GiB (the "2^10" measure) - they've always stated in KB / MB / GB since the beginning of time. RAM manufacturers have always used KiB/MiB/GiB because that's just how their addressing technology works.

I think it was mostly Microsoft (and only since Windows - I don't recall DOS ever doing this) that started dividing hard drive storage space by 1024 as well. It's not an industry standard. Apple doesn't do this - they divide by 1000 for storage and 1024 for memory - and display both as MB... go figure. Linux distros are generally explicit about MB vs. MiB, which is probably the best thing to do. Older Unix flavors on 'ls --block-size' allowed you to specify "MB" (divide by 1000) or "M" (divide by 1024).

Hard drive manufacturer can't know which operating system you're going to use, so they just stick with the precedent in their industry.

 

[scaesare]

Tesla is (most likely) technically in compliance with laws/regulations/standards, it's just that these laws/regulations/standards are not what the consumers expect.

We accept the ratings for battery packs for things like laptops or portable tools. Yet in those instances almost assuredly the product vendor are using the nameplate ratings from the manufacturer of the batteries.

So why are some folks expecting differently with Tesla?

I suspect it's because of instrumentation. Your laptop or drill doesn't provide any way to correlate energy used with Wh ratings. You just want a long enough run time or sufficient power delivery. The Model S, being a rolling computer, provides some data, and that has spurred more individual cell testing.

The result: the same for the car as for the laptop and the tools. The nameplate rating is not something that you will see with typical product usage.

But, until the industry as a whole opts to rate batteries differently, I don't see reason to deride Tesla, provided their pack rating is reasonably in line with the manufacturer's cell rating.

 

[supratachophobia]

What I find interesting is that while, yes, the car achieves its EPA rated range when you first get it, you slowly have decreasing range as you own the car. It sure would be nice to have that extra 4kw as a buffer to keep the EPA rated range for longer. Basically how the Mercedes B class does with the Tesla power train. It slowly dips into the hidden capacity so the driver always has the advertised range available.

In addition to that, the additional 4kw would allow for fewer cycles on the pack and make the degradation less gradual from that end as well.


But I'll counter my own argument and say that if we are really going to accept the argument "well ICE cars do xxx, so it's OK for Tesla to" then ICE lose MPG over their operational life as well so that after a few years, they won't achieve their EPA rated range either under any circumstances. Unfortunately, I was under the impression Tesla was a different kind of company, do it doesn't sit right with me to use that argument as well.


Thankfully even if that answer becomes accepted, they still are a different kind of car company in many other good ways. Still a customer to be found here, no worries.

 

[JRP3]

You are still not getting it.... 81kwh ESTIMATE reported by the BMS is based on driving the car. if you simply parked the car and left the stereo on (or turned the car off because it is really always on) the battery pack would deliver more than 81kwh

No it wouldn't because the car will never allow the pack to be drawn to 0 SOC.

the amount of Wh a cell delivers is dependent on the current, temp, and a few other factors

This is true, and it's why the name plate rated capacity of a cell probably never reflects it's actual real world capacity. I think what some people need to realize is that this is a new industry, (EV's), and some of the standard practices such as pack ratings probably need to be adjusted for the market. Tesla took the nameplate cell capacity from the manufacturer and rated it's pack accordingly, as is standard in the battery industry. No deception intended, IMO.

 

[pupik]

Has anyone thought about the cause of never ending discussion about range and capacity?
I think the reason of never ending discussion about the size of range is that it’s just still small.
If the range of Tesla was doubled, no one would care.
Moreover advertised range of Tesla is extremely exaggerated. Well, at least 30 % more than really is.
It’s theoretically range in unreal conditions like: cold in a car / flat landscape / speed < 50 mil. Who’s driving like that? Elon? :wink:
Tesla marketing wants to make the number on a dashboard interesting like for example 300 mil. But every owner of Tesla tells you that 200 mil. can be barely achieved when you don’t waste by the energy. It is like driving a gas car with 30kW
So why is a number 280mil on a dashboard so high, when the trip planner shows on average distance 280mil -30 % bat. of range?
That’s what I really don’t like on my display of Model S. I have to convert it over and over again or better I have to choose a final destination in my navigation and after that the trip planner shows correctly the remaining range.
Well, but everyone who joins me in my car wants to immediately know what the number on the display is! “Is it range? “Is it range?” And I would suppose to say: “No, it’s not accurate number, the range is 30 % lower”, but instead of I always say: “Yes, this is a range.” …and I obviously lie to them!
This is what Tesla should really change!
- the first marketing crap is 692hp -> 463hp
- the second is 85kW -> 78kW
- the third is 280miles -> 220miles
...what is gonna be next?
I don’t want to lie to my friends anymore….
Modesty is virtue, Elon ! :smile:

 

[JRP3]

I'm pretty sure a number of people have achieved rated range without extreme hypermiling. Range, like MPG, is rated under a set of conditions. Real life will rarely equal that exact set of conditions, no matter what conditions you pick. Everyone knows your mileage may vary, as will your range in an ICE. Yes once range is greater, and charging faster and more widespread, the issue will go away.

 

[CO2CLEAN]

This is what Tesla should really change!
- the first marketing crap is 692hp -> 463hp
- the second is 85kW -> 78kW
- the third is 280miles -> 220miles
...what is gonna be next?
I don’t want to lie to my friends anymore….
Modesty is virtue, Elon ! :smile:

First: tests show the P85D has about 415 kW of power or about 556 hp.
Second: Most (if not all) car manufacturers use the total theoretical capacity of the battery, not the usable (Volvo, Nissan, BMW, VW just to name a few).
Third: There are standardized tests (NEDC in Europe) that make it possible to compare vehicles. It is common knowledge that these tests do not represent realistic daily driving. This is the same for every car, however these tests make it possible to compare vehicles.

Tesla would be crazy not to use the outcome of the standardized test for range if all other car manufacturers do.

I do however agree that Tesla should add an option to use (for example) the average consumption of the car to calculate the range. I think this would help a lot of people better understand how far they can drive at any given moment.

 

[kennybobby]

... If batteries are kept in strictly controlled storage and not used, they will lose some capacity due to self-discharge.

That is considered an urban legend by folks who have actually tested cells for this, e.g. jack rickard over at evtv.me, and others have repeated his experiments. The websites you linked made statements of 2-3% loss without data or proof or peer-review, so you assumptions and conclusions cannot be accepted as true.

 

[dsm363]

You could boot it via a Live USB, for example. The point is that it's easily doable without any hardware modifications to the computer itself.

If we are going to ask Tesla to be 'reasonable' and advertise something practical and what a non-technical person could understand and achieve then this isn't realistic. Most people own a computer with one hard drive and have the OS on that one hard drive.

 

[bridaus]

When you remove the awesome data from this post (wk, okashira, others), this is all you hear:

One side: We want Tesla to be different in every way and this includes reporting brutally honest real world (instead of nameplate ) battery capacity numbers despite what ALL other companies do (laptops, phones, other BEV manufacturers). Even if it is at the expense of their bottom line and (like all companies) survival. It will make us feel better about the one company we want to love (or hate or short). We want the world to be about us and our ideals, and not about the reality of marketing, profit (the life blood of any company) and engineered specifications.

The other side: We realize it's a marketing number based on a perfect world rating (like most numbers called "specifications"), and it's really interesting to see and learn from the data how the car is engineered and marketed.

Overall, if you buy the car based on the kwh rating instead of how the range (and other features) fit your needs, you are foolish. Just as if I bought a car based on the size of it's gas tank or engine. They are all marketing numbers with little relevance to the actual intended purpose.


BTW, I have no data myself (other than my own purchase experiences of three different BEV's) so I'm open to being shut-up by some good numbers and technical discussion. Popcorn being consumed.

 

[MuppetOwl]

First: tests show the P85D has about 415 kW of power or about 556 hp.
Second: Most (if not all) car manufacturers use the total theoretical capacity of the battery, not the usable (Volvo, Nissan, BMW, VW just to name a few).
Third: There are standardized tests (NEDC in Europe) that make it possible to compare vehicles. It is common knowledge that these tests do not represent realistic daily driving. This is the same for every car, however these tests make it possible to compare vehicles.

Tesla would be crazy not to use the outcome of the standardized test for range if all other car manufacturers do.

I do however agree that Tesla should add an option to use (for example) the average consumption of the car to calculate the range. I think this would help a lot of people better understand how far they can drive at any given moment.

No the P85D has 469 hp as stated on the Tesla website now. And max disharge power that wk057 has read from the "code" is 350.22 kW 470hp

Also I did dyno the P85D in a dynomite dyno and got 435 on the hubs.

So where do you get the 415 kW (556 hp) number from?

 

[tomas]

I do however agree that Tesla should add an option to use (for example) the average consumption of the car to calculate the range. I think this would help a lot of people better understand how far they can drive at any given moment.

they do. Trip graph in the energy app. Very accurate, and it re-forecasts based on how you are driving.