davewill
Active Member
No, they wouldn't have cared. The EPA range should just go from battery full until the car stops.
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I think my car is lying to me...
- Thread starter supratachophobia
- Start date
I agree with you that something is not adding up here. I don't think most people experience what you are in that they lose 4-6% immediately at some point in their drive. But I don't have TM-spy to check out the numbers in my car. But I do know that I never achieve rated miles at 290 Wh/mi, even though the energy graph says that.
When you recharge from 0% to 100%, how many kWh do you add back to your car?
Brando
Active Member
Have a 110v charge cable. OR Find a Motor home park (some campground even) - I even think some Tesla owners register with PlugShare.
rent a portable generator The world runs on electricity it can be found most anywhere there are people.
I have never ran out of gas (since 1966). You?
IF it is really this stressful for you buy a hybrid. really isn't worth all this stress you are showing - avoid the stress, avoid the problem.
In a few decades when ONLY BEV are available you'll be fine.
good luck, chill out, (perhaps this stress isn't good for you)
Since you are so aggressively wanting scientific accuracy, please stop saying watts per mile.
Disclaimer: Didn't read the entire thread.
Huge amounts of degradation in a short time on a 90-pack is not surprising at all. Tesla fudging things to hide that degradation...... well, also wouldn't be surprising, but I haven't seen evidence to suggest they are actually doing this. I could be wrong, as I haven't taken a lot of time to investigate this issue lately.
The 90-type batteries are horrible on the degradation side of things. By now I estimate that a huge number of "90"-packs have less usable capacity than older "85"-packs in the fleet. The degradation "curve" of a 90-type pack (if you can call it a curve... looks more like a linear plunge into oblivion) is something like 5x steeper than the 85-type, and doesn't seem to level off as readily, either. While with the 85-type cells the degradation slows eventually, I've not seen this in the 90-type cells.
As noted in a previous thread, the crossover point between where an 85 and 90 vehicle have the same available capacity is only something like 30-40k miles. After that the 90-pack will forever have less usable capacity than an 85 of the same mileage, on average.
Anyway... I have limited time I go over everything, but long story short, I would take your complaints about 90-pack capacities to Tesla and/or relevant consumer protection entities. Tesla really screwed over 90-pack owners.
Huge amounts of degradation in a short time on a 90-pack is not surprising at all. Tesla fudging things to hide that degradation...... well, also wouldn't be surprising, but I haven't seen evidence to suggest they are actually doing this. I could be wrong, as I haven't taken a lot of time to investigate this issue lately.
The 90-type batteries are horrible on the degradation side of things. By now I estimate that a huge number of "90"-packs have less usable capacity than older "85"-packs in the fleet. The degradation "curve" of a 90-type pack (if you can call it a curve... looks more like a linear plunge into oblivion) is something like 5x steeper than the 85-type, and doesn't seem to level off as readily, either. While with the 85-type cells the degradation slows eventually, I've not seen this in the 90-type cells.
As noted in a previous thread, the crossover point between where an 85 and 90 vehicle have the same available capacity is only something like 30-40k miles. After that the 90-pack will forever have less usable capacity than an 85 of the same mileage, on average.
Anyway... I have limited time I go over everything, but long story short, I would take your complaints about 90-pack capacities to Tesla and/or relevant consumer protection entities. Tesla really screwed over 90-pack owners.
Common mistake.... Should be Kwh. (Kilowatt Hours) Watts is a rate where watt hours is an amount. Kilo= 1000
I will do just that, thank you.
I've been logging data and found that somewhere between 87% charge (69.2 nominal/65.2 usable) and 69.7% (56.0 nominal/52.0 usable), the car starts to calculate remaining range on something other than the nominal remaining number (but still not usable capacity as you might think). In other words, prior to 87%, it is exactly spot on if you take nominal kwh divided by EPA watts per mile, gives you estimated range. After that, it starts to wise up and seem to say "wait, we can't use that extra 4kwh, better change the calculation". Of course, that's not accurate to how far you can go, but at least we see where they go the number.
So below 87%, the estimate corrects itself by about 2% until somewhere after 19.1% remaining (18.3 nominal/14.3 usable). Then you get the old rug pull out and 4% just goes away somewhere below that. Once that happens, the car is correctly using usable capacity to calculate remaining range based on 290 watts per mile EPA.
So .29kwh EPA?
Edit: I was just going off the data that @wk057 had pulled to figure out where the EPA numbers had come from.
Last 0-100%, I put 73kw into the car. Which comes out to 13-15% battery degradation from new.
Wk057, you may have answered this elsewhere in the forum. In a perfect world that Tesla agrees that that amount of degradation warrants a battery replacement, are there any 90kwh battery revisions that you know of that do not suffer from the same accelerated degradation and would therefore "fix" the problem more long-term? Thanks.
What you're looking for is watt hours per mile. If you look at some of the other comments just after yours you'll see that: wh/mi. An efficiency rating is about the amount of energy used per distance. An energy amount would be 1 kilowatt hour, or kWh. To avoid using cumbersome decimals or fractions, like having to say it's one third of a kilowatt hour per mile, they are dividing by 1,000 and using watt hours per mile so the numbers look a little more sensible like 250 or 300. Watts is a unit of power, which is a rate of energy usage, not an amount of energy. The rate of energy transfer from a Supercharger into the car would be in watts or kilowatts.
For those of you still interested, I feel like I'm uncovering a conspiracy....
It appears as though two 90kwh cars are reporting full charge range using Nominal Capacity (which includes the unusable 4kwh brick protection). An 85kwh car is using the proper Usable Capcity to report range at 100%. I'm going to continue to collect more data, but I can't believe I'm saying this, there appears to be an attempt to intentionally hide the battery degradation of the 90kwh packs.
For those that care to check themselves, simply use your CANbus tool to find the Nominal and Usable values, divide by your cars EPA watts/mile at 100% charge and see which number is being used.
It appears as though two 90kwh cars are reporting full charge range using Nominal Capacity (which includes the unusable 4kwh brick protection). An 85kwh car is using the proper Usable Capcity to report range at 100%. I'm going to continue to collect more data, but I can't believe I'm saying this, there appears to be an attempt to intentionally hide the battery degradation of the 90kwh packs.
For those that care to check themselves, simply use your CANbus tool to find the Nominal and Usable values, divide by your cars EPA watts/mile at 100% charge and see which number is being used.
I doubt you have uncovered a conspiracy so much as there just being confusion about what the different CANbus values really are indicating. I think the 85 and 75 cars are calculating the same way as your 90.
I think you mentioned before that you were getting 272 rated miles on a full charge. So if your car adds rated miles at 290 Wh/mile (just calculated from kWh added divided by rated miles added), then you have added about 78.9 kWh to your car. That can't include the 4kWh buffer because that energy never gets used. Yet it seems to be defined as the nominal full pack. Is that correct?
It's confusing, no doubt.
Actually, I've been doing some testing with both my Model 3 (approaching 10k miles) and an S on newer firmware with an older 90 pack (not my car). There is almost certainly some subtle number fudging going on with both.
On the Model S, when calculating energy usage from various BMS messages, the SoC (and thus rated miles) display appears to tick down a hair less per unit of energy than expected. Then, below 30%, this seems to ramp up to expected, and below 20% accelerates to worse/faster than expected... getting worse as SoC drops.
Comparing resting cell voltages throughout the cycle would also seem to confirm displayed SoC being higher than expected. I also calculate and compare reported power usage with other sources, such as debug messages from the inverters, which aren't lining up as expected nor as they did in much older firmware. I'm not sure when this disparity began.
Everything is pointing to there being some fudging going on with the Model S + 90 pack. I'm not going to pounce on Tesla on this just yet, as I only have one datapoint on this so far... and I'm going to give them a chance to explain.... but it's not looking good right now.
On the Model 3 I'm still working out exact details to decode on CAN, but I'm seeing something similar but possibly even more damning there. On my trips, efficiency would always seem to follow a pattern: bad for the first dozen miles or so, epic for the next 100-150 miles, and then worsen from there.... despite driving style. I chalked the initial inefficiency up to initial climate control and such... but haven't been able to explain the latter drop off, especially with consistent driving conditions.
Again, I haven't fully deciphered everything I'm looking at on the Model 3 CAN, so I could be misinterpreting some things... but if what I've decoded is correct......... then the 3 is lying about power usage for the first ~50% of SoC usage or so, making it look more efficient than it is during this time, then compensating for the lie during the remaining SoC. Starts slowly once at < 50%, and accelerates as you get closer to 0%. It's done in a way that makes it look like efficiency is worsening, when in fact power usage per mile hasn't actually changed.
Again again.... I *could* be wrong here... but I've gathered enough data so far to be pretty suspicious and worried about the actual efficiency of the Model 3. So far I've been able to drive it about 260 real miles on a charge with reasonable driving, which isn't terrible... but is only 82% of rated range. My lifetime Wh/mi displayed is also around 255, which is 13% higher than rated.
Long story short......... I see some evidence that suggests Tesla is trying to cover up extensive degradation of the 90 packs by shifting some apparent usage towards lower SoC, making the displayed SoC (and thus rated miles) show higher than actual SoC on the upper portions of SoC. This would seem to fit what @supratachophobia has been describing here. Again, I only have one data point currently, but I will be gathering more as possible.
And then with the Model 3........ I really just hope I'm wrong there. Because if what I'm seeing and interpreting is correct and affects all cars......... then Tesla is *really* going to have some explaining to do. Like, dieselgate type explaining. Crossing my fingers that I just screwed up somewhere.
On the Model S, when calculating energy usage from various BMS messages, the SoC (and thus rated miles) display appears to tick down a hair less per unit of energy than expected. Then, below 30%, this seems to ramp up to expected, and below 20% accelerates to worse/faster than expected... getting worse as SoC drops.
Comparing resting cell voltages throughout the cycle would also seem to confirm displayed SoC being higher than expected. I also calculate and compare reported power usage with other sources, such as debug messages from the inverters, which aren't lining up as expected nor as they did in much older firmware. I'm not sure when this disparity began.
Everything is pointing to there being some fudging going on with the Model S + 90 pack. I'm not going to pounce on Tesla on this just yet, as I only have one datapoint on this so far... and I'm going to give them a chance to explain.... but it's not looking good right now.
On the Model 3 I'm still working out exact details to decode on CAN, but I'm seeing something similar but possibly even more damning there. On my trips, efficiency would always seem to follow a pattern: bad for the first dozen miles or so, epic for the next 100-150 miles, and then worsen from there.... despite driving style. I chalked the initial inefficiency up to initial climate control and such... but haven't been able to explain the latter drop off, especially with consistent driving conditions.
Again, I haven't fully deciphered everything I'm looking at on the Model 3 CAN, so I could be misinterpreting some things... but if what I've decoded is correct......... then the 3 is lying about power usage for the first ~50% of SoC usage or so, making it look more efficient than it is during this time, then compensating for the lie during the remaining SoC. Starts slowly once at < 50%, and accelerates as you get closer to 0%. It's done in a way that makes it look like efficiency is worsening, when in fact power usage per mile hasn't actually changed.
Again again.... I *could* be wrong here... but I've gathered enough data so far to be pretty suspicious and worried about the actual efficiency of the Model 3. So far I've been able to drive it about 260 real miles on a charge with reasonable driving, which isn't terrible... but is only 82% of rated range. My lifetime Wh/mi displayed is also around 255, which is 13% higher than rated.
Long story short......... I see some evidence that suggests Tesla is trying to cover up extensive degradation of the 90 packs by shifting some apparent usage towards lower SoC, making the displayed SoC (and thus rated miles) show higher than actual SoC on the upper portions of SoC. This would seem to fit what @supratachophobia has been describing here. Again, I only have one data point currently, but I will be gathering more as possible.
And then with the Model 3........ I really just hope I'm wrong there. Because if what I'm seeing and interpreting is correct and affects all cars......... then Tesla is *really* going to have some explaining to do. Like, dieselgate type explaining. Crossing my fingers that I just screwed up somewhere.
juliusa
Active Member
Is that the number that suddenly drops by 4-6%? The number the NAV system is telling you will have remaining when you get there?
Or is it the battery SOC% that suddenly drops by 4-6%?
When you say "power usage" are you referring to the actual power readout, or change in SOC vs distance?
Would a voltage based SOC calculation explain the observed behavior? It may use blended voltage + coulomb and favor one over the other at the ends of the SOC range.
Not sure why the canbus values would be misreported. I think I mentioned this above, it's not like the numbers are just a couple off. The math lines up to almost the decimal so intentionality seems at play here. I mean, the customer is never supposed to see the values anyway, so if that data is will too, then it could really mess with the service side of things.
But yes, this is confusing, agreed.
Below 20%, I've witnessed both drops "live" so to speak. Does that answer your question?
Thank you for your testing. Any good way to compare notes on the 90's to confirm or deny a conclusion?