Wiki Sudden Loss Of Range With 2019.16.x Software

[Droschke]

Tesla's internal metric is 30% below fleet average, not 30% below new.

Yes, a dead battery has a much better chance of getting replaced than a severely degraded battery.

If you ever get your battery replaced because its capacity has fallen by 30% of the fleet average of the similar models, you are not driving a Tesla but riding on an e-bike

 

[Ferrycraigs]

From my understanding and what I see the Energy Graph is only the usable. This is where some of the confusion comes in with people who use TM-Spy because it shows the 4kWh buffer and it messes up the graph. So when the car reads zero TM-Spy will show about 5% depending on the pack size.

I have TMSpy and it tells me my Capacity is 59kWh. My calculations from the Energy graph comes out at around 58-59 kWhs so I had always assumed it excluded the buffer. If TMSpy includes the buffer I am even further up [email protected]#t creek than I thought.

 

[ran349]

Yes, a dead battery has a much better chance of getting replaced than a severely degraded battery.

If you ever get your battery replaced because its capacity has fallen by 30% of the fleet average of the similar models, you are not driving a Tesla but riding on an e-bike

Since degradation is not covered, by Tesla’s definition the fleet average could be a dead battery.

 

[DJRas]

I have TMSpy and it tells me my Capacity is 59kWh. My calculations from the Energy graph comes out at around 58-59 kWhs so I had always assumed it excluded the buffer. If TMSpy includes the buffer I am even further up [email protected]#t creek than I thought.

Then you certainly are deeply up the creek.
TM-Spy indeed does include the buffer in it's display.
I contacted the author about that several weeks ago and he felt it was the most accurate information even though you cannot access the buffer while driving.

 

[FooFenix]

Then you certainly are deeply up the creek.
TM-Spy indeed does include the buffer in it's display.
I contacted the author about that several weeks ago and he felt it was the most accurate information even though you cannot access the buffer while driving.

This is rather difficult to wrap one's head around. Putting aside TM Spy, just with regard to the info displayed by the car itself. Are we actually saying that the "projected" range assumes ALL energy stored in the battery will be used, INCLUDING the buffer?

In that case the car is projecting you can and will travel that distance and consume that energy, hence including the buffer. While setting a buffer aside should be meant to avoid drivers actually use that energy and hence brick their battery.

Something doesn't make sense here. I mean "By design", irrespective of the ongoing discussing about capping.

 

[Droschke]

Since degradation is not covered, by Tesla’s definition the fleet average could be a dead battery.

You mean your battery must be 30% deader than dead?

 

[N..8]

So, you agree with @Ferrycraigs's recommended formula to be a good approximation of the pack's capacity?

The math works to about +- .2 of the total pack. The problem with the Energy Meter in the car (my belief) is that it's doing a calulation at that moment and making the numbers work. What I mean is that from a basic point, if it says projected is 100 miles and you've averaged 275 Wh/mile you would think that as long as you go 275 Wh/mile you can go 100 miles. I don't think this to be the case though because that projected is using total pack rather than usable. So I think Tesla makes the numbers to always update, maybe on a per mile bases. Then as it gets closer and closer to the 4kWh remaining buffer it starts to manipulate the numbers. In another thread on here I was talking about it a few months back we were saying that the 295 Wh/mile isn't achievable. The math for Rated Range only works at 100% full using Total Pack kWh.

 

[Droschke]

I have TMSpy and it tells me my Capacity is 59kWh. My calculations from the Energy graph comes out at around 58-59 kWhs so I had always assumed it excluded the buffer. If TMSpy includes the buffer I am even further up [email protected]#t creek than I thought.

That hurts ... Your capped battery might be 55kWh now?

 

[DJRas]

This is rather difficult to wrap one's head around. Putting aside TM Spy, just with regard to the info displayed by the car itself. Are we actually saying that the "projected" range assumes ALL energy stored in the battery will be used, INCLUDING the buffer?

In that case the car is projecting you can and will travel that distance and consume that energy, hence including the buffer. While setting a buffer aside should be meant to avoid drivers actually use that energy and hence brick their battery.

Something doesn't make sense here. I mean "By design", irrespective of the ongoing discussing about capping.

No, The car's displayed data does NOT include the buffer.
HOWEVER, the car does not display kWh capacity anywhere available to the layman (only with root access/developer mode).

The display ONLY shows percent and Range values.
As @Ferrycraigs noted you can get an approximation of capacity following his math.
But, it will be off by 5% at best.

 

[Droschke]

Are we actually saying that the "projected" range assumes ALL energy stored in the battery will be used, INCLUDING the buffer?

I would say yes. How else they can justify you bought ~85kWh battery? They have to fudge the math to get as close as possible to what that badge slapped at the back of our cars says.

 

[Droschke]

As @Ferrycraigs noted you can get an approximation of capacity following his math.
But, it will be off by 5% at best.

Would you tell me where the 5% + - comes from? His TMS and own formula very closely match.

 

[DJRas]

I would say yes. How else they can justify you bought ~85kWh battery? They have to fudge the math to get as close as possible to what that badge slapped at the back of our cars says.

The Range estimates do NOT include the buffer.
The 85 kWh battery designation was wrong and readily admitted to by Tesla YEARS ago.
Jason showed the Rated Range and Usable capacity of about 78 kWh combined with the 295 Wh/mile "constant" though he measured the packs at having 81-82 kWh of actual battery capacity.

 

[DJRas]

Would you tell me where the 5% + - comes from? His TMS and own formula very closely match.

Rounding errors using rounded whole numbers for range, percentage and kWh values displayed.

 

[Droschke]

Rounding errors using rounded whole numbers for range, percentage and kWh values displayed.

Thanks. Back to do my calculations for 20th time.

 

[N..8]

No, The car's displayed data does NOT include the buffer.
HOWEVER, the car does not display kWh capacity anywhere available to the layman (only with root access/developer mode).

The display ONLY shows percent and Range values.
As @Ferrycraigs noted you can get an approximation of capacity following his math.
But, it will be off by 5% at best.

DJRas, I use TM-Spy which does include the buffer in it. I've driven my car down to Zero displayed range and TM-Spy shows 4kWh. Using the Cars display and Rated range it does include the reserved range at the start then it curves it out as it goes down in range.

 

[Droschke]

DJRas, I use TM-Spy which does include the buffer in it. I've driven my car down to Zero displayed range and TM-Spy shows 4kWh. Using the Cars display and Rated range it does include the reserved range at the start then it curves it out as it goes down in range.

So, the car projected range is off by up to + - 4kWh, or by up to + - 12 miles (assuming 1kWh gets you 3 miles on S85 on average).

Can we agree on that?

 

[DJRas]

DJRas, I use TM-Spy which does include the buffer in it. I've driven my car down to Zero displayed range and TM-Spy shows 4kWh. Using the Cars display and Rated range it does include the reserved range at the start then it curves it out as it goes down in range.

I have not redone this table since they gave back 8 miles range.
But this shows that SOC is DIRECTLY proportional to Remaining Usable kWh divided by USABLE Full pack
Further that Rated Range equals Remaining Usable kWh divided by ~276 Wh/mile.
This works all the way from 100% to 2% SOC.

 

[Droschke]

I have not redone this table since they gave back 8 miles range.
But this shows that SOC is DIRECTLY proportional to Remaining Usable kWh divided by USABLE Full pack
Further that Rated Range equals Remaining Usable kWh divided by ~276 Wh/mile.
This works all the way from 100% to 2% SOC.

@DJRas,
Using the @Ferrycraigs formula, I'm 4kWh more in capacity than using the 276wh/mi. That tells me the projected range includes the 4kWh buffer at worse.

 

[N..8]

I have not redone this table since they gave back 8 miles range.
But this shows that SOC is DIRECTLY proportional to Remaining Usable kWh divided by USABLE Full pack
Further that Rated Range equals Remaining Usable kWh divided by ~276 Wh/mile.
This works all the way from 100% to 2% SOC.

DJras, I'm not sure what the 276 Wh/mile is, but if you add the 4 kWh into the pack does that change your number to 295 Wh/mile?

Edit,

I did the math if you add in the 4 kWh you will so called use the 295 Wh/mil

 

[drummerboy7816]

This is insanely unethical and shady.. I bought a used CPO 2015 85D few months back. At the time my rated at 100% was around 265, now after this update, I'm at 236 or so.. that's almost 30 miles lost.