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Raven Model S Range 360 Miles

Raven Model S Range 360 Miles

Although I love my new Model S, I was surprised the rated range is 360 not the 370 advertised. Anyone else seeing this?

gordo | 3 juni 2019

How many times have you charged it? Rated range floats around a lot, especially if you're not emptying and filling it from time to time.

richard_lawson | 3 juni 2019

@Gordo, just once all the way. I don't have a need for the full range for the daily drive.

ran349 | 3 juni 2019

Don't worry about it. It will go down from there.

carlk | 4 juni 2019

Not sure if you need to do it for a new battery but this is how battery balancing is done. You need to first let it run to close to zero and than charge to 100%. I wouldn't worry about doing it if I were you though.

https://teslamotorsclub.com/tmc/threads/battery-balancing-worked.136176/

avesraggiana | 4 juni 2019

@ran349 Hahaha!

Tropopause | 4 juni 2019

In my case (Model 3) it went up from there.

p.c.mcavoy | 4 juni 2019

@carlk - The link you posted on battery balancing is outdated with regard to how balancing actually works based upon comments posted on TMC by wk057 in April this year. His comments are buried in a fairly long thread about battery capacity. I think this link will take you to the correct page in it.

https://teslamotorsclub.com/tmc/threads/teslas-85-kwh-rating-needs-an-as...

You need to look for entry #1131 in that thread dated April 21, 2019. Just a part of his comments having extensively reverse engineered the BMS are included below. He refers to it now as a work of art. His conclusion is the car now balances whenever it needs to balance.

p.c.mcavoy | 4 juni 2019

Just a few extracts from the TMC post by wk057 ...

“Tesla has changed the balancing algorithm many many times over the years. Originally this was a very dumb setup that would only kick in once a cell group reached a threshold voltage, usually around 90-93% SoC. This is no longer the case.

The car balances all the time whenever its needed. It knows when a cell group will need balancing before it's even out of balance... which is really freaking weird when you think about it, especially if you're watching a playback of the pack balancing and voltages and see it engage a balancer on a cell group that doesn't look out of balance at all, and watch it fall completely in line still at the end of a charge or discharge cycle. It keeps track of which groups will need it, which wont, how long they'll need it, how much they've been balanced, etc.

It really is an epic setup now.

The short answer to the balancing question: It balances any time it needs to balance.

As for SoC shenanigans, yes getting closer to 100% or 0% will give it a chance to tune things better... but it's not needed anymore. Just charge like you need to, and drive.“

JChun | 4 juni 2019

I've had mine for a few weeks now, started at 360, is up a few miles at max charge getting closer to 370. I've already put almost 3k miles on it so far, driving a couple of long trips from Boston to Baltimore round trip and Boston to NYC. There are some quirks that take getting used to, but I 100% agree w Joe Rogan, driving another car makes them feel stupid. This is the most fun I've had driving since I've been driving.

TeslaTap.com | 5 juni 2019

@p.c.mcavoy - Good find at TMC. Note that Wk056 was talking mostly about cell balancing, which is different than the calibration of the visual SOC. I'm less clear if he's saying the visual SOC calibration occurs all the time or he agrees it is as we've known in the past - needs a low STC to 100% charge cycle. I'd expect the cell balancing to also slightly affect the real SOC downward, but no idea as to how much.

TeslaTap.com | 5 juni 2019

I'm introducing two terms here - visual vs real SOC. The battery has a real SOC - the amount the battery truly holds and is independent of the visual SOC. The visual SOC, is what is displayed on screen and is a calculation. Ideally you want the real and visual SOC to be the same, but for a lot reasons, this is really difficult - especially when draining the battery (i.e.driving) so the visual SOC ends up being a good estimation. It can be fairly accurate, but it can also drift over time, and Tesla purposely makes this drift go slightly downward from the real SOC over time. Consider if the drift was upward, you'd run out of power with some SOC remaining, so safer to go downward. The problem is the drift is cumulative. If Tesla does not calibrate the SOC (which happens at 100% SOC), the visual (not real) SOC will go down over time.

TeslaTap.com | 5 juni 2019

So I'm less sure the SOC is super accurate all the time. I do trust the work Wk056 does, but I either missed it or he is not claiming SOC is accurate all the time - just that cell balancing is done at any SOC now. That's cool from a technical perspective. I can see the additional cell balancing may reduce the errors in the visual SOC somewhat.

TeslaTap.com | 5 juni 2019

...needs a low SOC to 100%...

Forum made me break text up into 3 posts :(

p.c.mcavoy | 5 juni 2019

@TT - minor point, but it’s wk057. He’s actually a notch above in knowledge from 056! :-)

Maybe I should have just copied in his full post versus extracted parts. (I also was fighting forum not letting me post it all in one and had to spit it up!). While the sections I posted above do speak most to cell balancing, wk057 also makes this statement in the same post. Part of this section (at least to me) speaks directly to his view of their ability to calculate the capacity of individual bricks (groups of 96 cells) “with almost magical accuracy”. Also look at his very final comment. Going very low and to 100% helps with fine tuning SOC, but his view it’s really no longer needed.

I’ll post his full entry below, but may need to break it up into sections ...

p.c.mcavoy | 5 juni 2019

From wk057, April 21, 2019. - Part 1:

Worth an update here.

Tesla has changed the balancing algorithm many many times over the years. Originally this was a very dumb setup that would only kick in once a cell group reached a threshold voltage, usually around 90-93% SoC. This is no longer the case.

First, let me point out that Tesla's BMS software has come a LONG way... I'd consider it a work of art now. Lots of genius in there. It's absolutely amazing and full kudos where kudos are due here.

One thing they're now able to do is to calculate out the capacity of individual bricks of cells (96 in the 85/90/100, 84 in the rest) based on a ton of factors and compute this in near real time, in a full range of conditions, with almost magical accuracy. They're basically running physics simulations (similar to how they calculate out unmeasurable metrics in the inverter firmware, like rotor temperature) of the entire pack based on measured power usage/charge, balancer usage, temperature, temperature delta based on coolant flow and coolant temp, predicting temperature gradients, and probably 100 more variables. This is the holy grail of proper balancing for safety and longevity for a battery pack. This is not a dumb system anymore by any means. Knowing the actual capacity of the individual bricks allows them to know exactly which ones need cell bleeders enabled, and for exactly how long. With this data, they can balance on the fly at any SoC, and just use top and bottom SoC windows for fine tuning, validation, and calibration.

p.c.mcavoy | 5 juni 2019

wk057, April 21, 2019 - Part 2:

The car balances all the time whenever its needed. It knows when a cell group will need balancing before it's even out of balance... which is really freaking weird when you think about it, especially if you're watching a playback of the pack balancing and voltages and see it engage a balancer on a cell group that doesn't look out of balance at all, and watch it fall completely in line still at the end of a charge or discharge cycle. It keeps track of which groups will need it, which wont, how long they'll need it, how much they've been balanced, etc.

It really is an epic setup now.

The short answer to the balancing question: It balances any time it needs to balance.

As for SoC shenanigans, yes getting closer to 100% or 0% will give it a chance to tune things better... but it's not needed anymore. Just charge like you need to, and drive.

Munka | 5 juni 2019

Can I just add that the trick to getting the maximum enjoyment out if your Tesla is to learn as much as you can about your battery and then set it to % and most importantly do whatever you can to forget it all!

At 370 mile range this statement is truer then ever! Just enjoy the car. If you want to learn for acadmic purposes be my guest, but please don't give it a second thought while driving.

ALSET | 8 juni 2019

I have 455 miles on my 2 week old Raven S...and I'd like to just clarify kWh, Wh/mile, range, etc. I just did my first semi-long drive and on the trip window it says since my last charge I have:

141.4 miles
37.5 kWh
265Wh/mi

Doing some easy calculations on the calculator I'm getting 377 mile range if I were to drive like this for a 100% charge? The battery though is locked out to something like 95% right? And you never want to get to 0% so that leaves me in the 370 range? Am I looking at this right? Thanks!

Tropopause | 8 juni 2019

265 Wh/mi is so awesome for a big Model S. Tesla keeps distancing themselves from the competition.

p.c.mcavoy | 9 juni 2019

It's hard to judge how awesome 265 Wh/mi without any indication of the average vehicle speed and terrain. I did one stretch in my mid-2016 MS90D where I traveled 306 miles continuous in one stretch with the trip meters indicating 72.9 kWh total energy consumption with an average 238 Wh/mi. This were perfect conditions, able to run most of it without any AC or heat, no wind, and I was clearly in conservation mode for about 60 miles of that trip.

I'm not contending that my old MS is more efficient that a new one, or that the efficiency improvements of the new MS is not a good step. It's just that you need to take everything in context and there's not enough here to tell me what the equivalent Wh/mi rate constant is for the new models.

Tropopause | 9 juni 2019

Agree but 265 Wh/mi jives with the results Motor Trend achieved on their Fremont to Hawthorne drive so I was happy to see a real person get the same. Hope to hear more owner reports to confirm.

ran349 | 9 juni 2019

ALSET,
To figure out what you are looking for you need to know at what rate you consumed rated miles. So you would need to know how many rated miles you consumed from your battery during your trip, which you didn’t provide in your data.
As an example, let’s say you used 150 rated miles from your battery during your trip. Your consumption rate would be 37.5 kWh/150 miles = 250 Wh/mi. Take that number and divide by your actual Wh/mi of 265 = 250/265 = .9434. Then multiply this by your 100% rated miles on your battery. So, if your 100% charge is 370 miles, your actual obtainable mileage would be .9434 x 370 = 349 miles.
The key is knowing what rate your car consumes rated miles and then doing the ratio to your actual performance.

ALSET | 9 juni 2019

@ran349 - thank you for explaining that. Where do I find my rated miles? Is that when I can choose between seeing my "battery %" or "miles"? Since I bought the car it didnt line up with the claimed 370 miles. As an example, if I set the display to miles instead of percentage at 70% I get 253 miles even though 70% of 370 should be 259 miles. I'm always off a few miles if I assume 370 is the max. I'm not sure if this is what you meant by rated miles.

p.c.mcavoy | 10 juni 2019

@ALSET - Yes, when folks say rated miles, it's the number that will be by the battery icon if you set the display to "miles".

ran349 | 10 juni 2019

@ALSET- Yes, as has been stated, you are correct in what is considered rated miles. And even though 370 is the spec for your car, it is not uncommon to start out at a slightly smaller number like you have.
So for the example I used, if you had charged to 70% prior to your drive, you would get approximately 239 actual miles by driving at 265 Wh/mi. Of course, like others have said, your driving Wh/mi is highly variable, depending on driving conditions like weather, wind, speed, and terrain. You will quickly learn this with experience driving your car.