TeslaFi battery report range increase of over 10 miles after update ?

[Alset2]

It's good enough. His new constant is 69400Wh/282mi = 246Wh/Mile. (It's nominal minus buffer - the usable capacity, that's used for the Rated Range math)

This compares to his earlier shot which was 69300Wh / 271 miles = 255 or 256 Wh/Mile.

So am i understanding correctly that the update lowered the efficiency ( or raised as the case may be) and that's what increased the range?
Instead of it using 255wh/mile to calculate , it now uses 246wh/mile , which gives me more range as far as "reports" go?

 

[Alset2]

Not quite right. You need to show full rated range.

Would it matter or give more info if I get one with all this info?

 

[serendipitous]

That's not correct. The rated range constant is equal to full pack divided by full rated miles. That is the actual constant that Tesla uses in their firmware when calculating rated miles. It is an exact number that never changes, unless Tesla changes it in the firmware, which it looks like they did in his case.

The whole point of this thread and of the software update in question is that the constant DID change, this one time. The Rated Range is the car's estimate of the Usable (Nominal - Buffer) battery power divided by that constant.

The change in this software release has nothing to do with actual range - all it does is show a bigger number since they had a better EPA rating than it shipped with.

 

[serendipitous]

Instead of it using 255wh/mile to calculate , it now uses 246wh/mile , which gives me more range as far as "reports" go?

Yep. The motors use the same energy, the battery has the same capacity - only the "MPG" changed on the display.

 

[ran349]

Would it matter or give more info if I get one with all this info?

It doesn't really matter. I was just trying to get the exact number. But I can estimate from your previous chart that it looks like your charge constant went from 270 to about 260 Wh/mi, which gives you more rated miles.

But of course it doesn't mean you have more energy in your battery, or that you can drive any farther in actual miles. It's just a different definition of how much energy is in a rated mile.

It would be interesting to know how Tesla would define degradation in that case where they changed the constant. It looks like you have about 4% degradation with the assumption that when new the nominal full pack value was about 98 kWh, and now is 94 kWh.

 

[Alset2]

Ok, thank you all for the info.

I understand what you all are saying, my car has not changed, update simply manipulated the numbers .

That does make things interesting for measuring degradation (and convenient if you have to uphold a warranty based on this #) .

So I don't base degradation from 100kw?

Another simple confirmation if you don't mind ,to get the rated range , I would have to have the energy meter (set on 30 miles) down to around 246 wh/mile ? Is this the correct line of thinking?

Before I learned all of this about buffers and such, I was always figuring I needed to get about 270 wh/m which would be 3.7 miles x 100kw =370 miles of range. However, with buffer and 6% degradation (based on full 100kw) I would have 89kw (at 100% charge) usable and I would need to use the formula 4.16 mile per wh or 240wh/mile to achieve rated range ??

I understand now that I never had 100kw of usable, so my actual degradation is only about 4%, which feels a little better than 6%....

Sorry I maybe really confusing this math .

Basically , in my mind, I need to figure that I really only have 89 usable KW at 100% charge. If I can achieve 250 wh/mile that would give me 4 miles per KW. 4 x 89 KW = 356 miles of range at 100% - I'm just using round numbers here for reference .

Another way to look at is for every 1 % of display range, its really = 1.13 kw (roughly) NOT 1KW based on usable 100KW

Sorry for the rambling stream of consciousness here, but I Do appreciate the time to make sense of this for me. ( or try...lol)

Thanks
Neil

 

[Alset2]

BTW ,I just noticed those rating ICONS, is it customary to give a rating to posts when people are answering your questions?