Supercharger did not take to 100% SOC

[ℬête Noire]

First time taking battery to "full", only about 1500mi on odometer. I set the limit all the way right and let the SC try take it to the ceiling. It spent a very long time post 97%, actually dropped to 97 after reaching 98, and then "bounced" like that between 99 and 98, before several minutes later stopping at 99% (on Distance it reads 307 miles).
Is it normal for it not to reach literal 100%?

 

[Remonster]

Normal? Possibly. Acceptable? I'd say definitely.

I think people are getting a too affixed on seeing 100% or 310 miles. In the end, plug it in and drive it around. You'll likely find that your "98% charge" takes you beyond 307 miles. Maybe not if you're driving like a mad man though.

My Model 3 has never been charged to 100% in the 5 months I've owned it. There's been no reason. Supercharging, normal L2 charging, and range displaying has always been accurate.

The best advice I've gotten from a veteran Tesla owner (OG Roadster Owner) is to not worry about it. Plug it in when you need, unplug when you've got the range you need, and drive it around. Profit!

 

[ℬête Noire]

Normal? Possibly. Acceptable? I'd say definitely.

I think people are getting a too affixed on seeing 100% or 310 miles. In the end, plug it in and drive it around. You'll likely find that your "98% charge" takes you beyond 307 miles. Maybe not if you're driving like a mad man though.

My Model 3 has never been charged to 100% in the 5 months I've owned it. There's been no reason. Supercharging, normal L2 charging, and range displaying has always been accurate.

The best advice I've gotten from a veteran Tesla owner (OG Roadster Owner) is to not worry about it. Plug it in when you need, unplug when you've got the range you need, and drive it around. Profit!

My intention is to be driving out at the edges of range, in Great Plains states & provinces. Range is critical.

Trying to understand if there is something technical Im doing wrong or missing. Not looking for a lecture about it not mattering.

 

[ewoodrick]

As the charge approaches 100%, the charging current is going to drop to a low number and it may take longer to go from 90 to 100% than 0 to 90%

For all other manufacturers, that why they spec to 80% charging and often limit DC fast charging to 30 minutes, after that a level 2 charger charges just as fast

 

[ℬête Noire]

As the charge approaches 100%, the charging current is going to drop to a low number and it may take longer to go from 90 to 100% than 0 to 90%

I waited until the Supercharger turned itself off. This was the SC's point of stopping, not mine. It disengaged and announced it had completed. Is there a way the change the Set Limit by explicit number? I mean without going 3rd party with Teslifi or similar tool? Just to make sure that isn't the issue, where I was unable to slide it to "100%".

I wanted to see where it thought it would stop, my understanding is that near full it starts work on balancing the different modules in the battery which doing so periodically is a good thing. Urban legend?

Of course as expected it took much longer during the top 30%, and progressively slower as it rose. You can see the rate ramping down (though I admit I napped most of the way through the 80's and 90's ).

 

[Zoomit]

For all other manufacturers, that why they spec to 80% charging and often limit DC fast charging to 30 minutes, after that a level 2 charger charges just as fast

Naturally, if you make categorical statements on the internet, others will correct you. This is one of those cases.

Manufacturers don't "spec to 80% charging". Only Hyundai/Kia limit DCFC to 94%, other don't at all. The 30 min limits for many 50kW stations are limited by the station not the car and it is a trend that's going away. DCFC is significantly faster then AC Level 2 until 98%, then it's the same speed.

 

[SomeJoe7777]

I waited until the Supercharger turned itself off. This was the SC's point of stopping, not mine. It disengaged and announced it had completed. Is there a way the change the Set Limit by explicit number? I mean without going 3rd party with Teslifi or similar tool? Just to make sure that isn't the issue, where I was unable to slide it to "100%".

Your issue is probably one related to calibration of the battery level meter. The Tesla's periodically calibrate the battery level meter based on charges and discharges, and if you haven't done a full range charge and/or a deep discharge (down into single-digits of percent) recently, then the calibration may be off. 307 miles sounds like the true full range counting for a few miles of battery degradation, it's just that the car hasn't equated that to 100% yet.

If you do a deep discharge and then another range charge, I bet the level meter now reads 307 miles / 100%.

 

[ℬête Noire]

Your issue is probably one related to calibration of the battery level meter. The Tesla's periodically calibrate the battery level meter based on charges and discharges, and if you haven't done a full range charge and/or a deep discharge (down into single-digits of percent) recently, then the calibration may be off. 307 miles sounds like the true full range counting for a few miles of battery degradation, it's just that the car hasn't equated that to 100% yet.

If you do a deep discharge and then another range charge, I bet the level meter now reads 307 miles / 100%.

Yeah, that's what I was trying to do here. I timed it down to 6% battery remaining (way lower than I've ever taken it.....that's even lower than I've ever taken the Bolt in nearly 25,000 miles of use) and plugged in at Rudy's on 290, on the way back from a friend's place. If I hadn't been such a chicken *sugar* I'd have driven over to North Houston SC where Nav was estimating it'd be 2% remaining.

Maybe the software just needs more time & use to gather data and sort it all out to finish calibration.

 

[jdw]

Below 93% charging is constant current. Above 93% charging transitions to constant voltage and slows considerably. This allows safer charging near the top end and also helps with more finely balancing cells.

The car only has an estimate of what 100% should be and if any cell banks are different enough from other cell banks then you may not get to what the car thought was 100% as some cells are at "100%" but others are not. To avoid overcharging the ones that are fully charged, charging stops.

Charging above 93% also triggers balancing, which takes a few days and runs regardless of the state of charge. It is likely that you will get to a full 100% on your second or third attempt after balancing has completed. No need to run the battery to a low state of charge to allow balancing at the top end of the battery - running 100% to a low range and back *may* help with calibrating range, but should have no effect on where 100% is.

The range gain from 99% to 100% in this case is tiny and likely unnoticable as the displayed range is just indicating that charging stopped a little short of what was expected - 99.9 still reads as 99 ...

 

[ℬête Noire]

Below 93% charging is constant current. Above 93% charging transitions to constant voltage and slows considerably. This allows safer charging near the top end and also helps with more finely balancing cells.

The car only has an estimate of what 100% should be and if any cell banks are different enough from other cell banks then you may not get to what the car thought was 100% as some cells are at "100%" but others are not. To avoid overcharging the ones that are fully charged, charging stops.

Charging above 93% also triggers balancing, which takes a few days and runs regardless of the state of charge. It is likely that you will get to a full 100% on your second or third attempt after balancing has completed. No need to run the battery to a low state of charge to allow balancing at the top end of the battery - running 100% to a low range and back *may* help with calibrating range, but should have no effect on where 100% is.

The range gain from 99% to 100% in this case is tiny and likely unnoticable as the displayed range is just indicating that charging stopped a little short of what was expected - 99.9 still reads as 99 ...

Ah, so the balancing process remains ongoing as long as the vehicle is charged up that high. I wasn't so much concerned about a couple miles (even if that's in the range of being a real margin of error buffer for what I'm attempting) as I was there was more an underlying issue going, with this only being a symptom of it.

So is the internal AC->DC that is used for L2 charging capable of the same fixed peak voltage control that the SC provides for those last few Wh? Basically, doing this at home would give the same effect?

 

[jdw]

The balancing process runs to completion once it is triggered, regardless of charge level or usage. Crossing the 93% threshold allows the BMS to identify higher voltage cells and to bleed them to the level of the lower cells, allowing the pack to more fully (evenly?) charge. The balancing process takes many hours or even days but there is no need to keep the car at any particular state of charge.

AC or DC charging has the same transition on the top end of the charge, so yes, the effect is the same at home. The older Visible Tesla app had a graphing section in it that showed the battery side of this very clearly - you could see the rate of charge slowing while the current dropped and the voltage remained constant.

What's non-intuitive about AC charging is that you have two systems, the AC side and the DC side and the DC battery is at a different voltage than the AC input, so as state of charge increases so does the battery voltage, which means that even at a sustained given kW input charge rate ("even draw" by the AC chargers) the current to the battery will drop as the battery voltage increases. At the very top of the charge, the battery starts to limit how much current it will accept, getting slower and slower until it hits the voltage limit of the highest cells.

These higher voltage cells are what stops charging early.

State of charge is basically the voltage of the pack. For an 85D, 100% SOC means a pack voltage of slightly above 400V and 0% SOC is somewhere around 330V.

 

[jgblair]

My intention is to be driving out at the edges of range, in Great Plains states & provinces. Range is critical.

The easiest way to extend range is to slow down and drive smoothly without rapid starts. Here is a chart for range versus speed:

Tesla Model S/X/3 range at 55/60/65/70/75/80 mph

 

[Lasttoy]

I tried 100 % a few times, it gets crazy above 95%. Mine is very happy at 95 and 225 miles.
Also, this is in our manuals .

 

[HopeToGolf]

First time taking battery to "full", only about 1500mi on odometer. I set the limit all the way right and let the SC try take it to the ceiling. It spent a very long time post 97%, actually dropped to 97 after reaching 98, and then "bounced" like that between 99 and 98, before several minutes later stopping at 99% (on Distance it reads 307 miles).
Is it normal for it not to reach literal 100%?

I am no expert but with ~6,800 miles on the odometer I’ll tell you about my experience.

Periodically, I take ~270 mile road trips. As a result, I charge to 100% before most of them. My recollection is I see 310 miles maybe 30% of the time. The charges have been driven by a household 110v, Charepoint Level 2, Clipper Creek Level 2 and Superchargers.

That said, I mostly charge to only 50% for my daily driving. In the latest situation (last night after a long drive to maybe 19% of the battery) I am at 155 miles (50% of 310).

In my first few weeks of ownership I was bothered because I was not getting an implied ~310 miles based on my % charge (whether it was 50%, 90% or 80%). Maybe I still should be but as of now, I don’t think about it much and assume the battery is doing it’s thing and there are lots of variables that impact whether I get an implied 305-310 miles.

I think your experience is normal. I have an opportunity to charge to 100% probably twice every 4-6 weeks. I see 310 miles very few times usually something like 307-310.

 

[ℬête Noire]

The easiest way to extend range is to slow down and drive smoothly without rapid starts. Here is a chart for range versus speed:

There are indeed multiple factors, I'm looking to work them all. Only so many hours in a day, too, and sometimes there are awkward stops.

In my first few weeks of ownership I was bothered because I was not getting an implied ~310 miles based on my % charge (whether it was 50%, 90% or 80%). Maybe I still should be but as of now, I don’t think about it much and assume the battery is doing it’s thing and there are lots of variables that impact whether I get an implied 305-310 miles.

Yeah, actual miles is a much different thing as there are all sorts of factors in there that have nothing directly to do with the car (weather, elevation, my driving choices, wheels). I'm not so worried about the mile readout, that was more "extra info in case it matters". I normally run in battery percent mode.

Anyway, I think the mystery is wrapped. Thank you everyone for he responses.

Fin.

 

[RedModel3]

I drove a Volt for two years. It was so much easier to immediately see the effect on range based on weather, hills, heat, AC, or how heavy my foot was.There were days I would GAIN range, and days where range just shrunk, especially in cold weather. In this one respect, any electric car is like any ICE car. How and where you drive it has an effect on range. It's simple physics. In a Tesla, we are told not to charge fully every day, like I did in the Volt, so it's more difficult to notice how the charge state of the battery can change from day to day.

So, try not to worry about it. Just drive it. If you don't drive it like you stole it, at least not all the time, you'll get better range regardless of your initial charge.

 

[SigNC]

I drove a Volt for two years. It was so much easier to immediately see the effect on range based on weather, hills, heat, AC, or how heavy my foot was.There were days I would GAIN range, and days where range just shrunk, especially in cold weather.

You can mostly see this in the new energy section of the v9 on the 3.

 

[ℬête Noire]

I drove a Volt for two years. It was so much easier to immediately see the effect on range based on weather, hills, heat, AC, or how heavy my foot was.There were days I would GAIN range, and days where range just shrunk, especially in cold weather. In this one respect, any electric car is like any ICE car. How and where you drive it has an effect on range. It's simple physics. In a Tesla, we are told not to charge fully every day, like I did in the Volt, so it's more difficult to notice how the charge state of the battery can change from day to day.

So, try not to worry about it. Just drive it. If you don't drive it like you stole it, at least not all the time, you'll get better range regardless of your initial charge.

Supercharger did not take to 100% SOC

:/

Google Maps

Net elevation change is about 360Wh worth, with no meaningful hills at the end of the route. This is a tight route.

 

[tomas]

@jdw posted the correct answer. I’ve had the last 1% take hours at home. I suspect (and hope) Tesla has programmed superchargers to stop at some point so people don’t take up stalls for hours to get last mile.

 

[RyanT]

I’ve had the last 1% take hours at home.

Yep, same here. For whatever reason the model 3 takes more time to balance than my model S did. I think it took like 3 hours the other night!