Heat degrades batteries faster. Supercharging causes the battery to heat up much more significantly than regular home charging so yes, Supercharging does degrade batteries faster. A more nuanced answer would be that if you only occasionally Supercharge on a road trip, you won't notice the battery degradation. For example, I've done maybe 5 road trips and Supercharged less than 10 times. I would probably have immeasurable degradation from Supercharging. If 25% of your charging was done on a Supercharger, I would think you'd have much more degradation than the scenario I outlined previously.
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Range Loss Over Time, What Can Be Expected, Efficiency, How to Maintain Battery Health
- Thread starter KK_RedM3
- Start date
Heat degrades batteries faster. Supercharging causes the battery to heat up much more significantly than regular home charging so yes, Supercharging does degrade batteries faster. A more nuanced answer would be that if you only occasionally Supercharge on a road trip, you won't notice the battery degradation. For example, I've done maybe 5 road trips and Supercharged less than 10 times. I would probably have immeasurable degradation from Supercharging. If 25% of your charging was done on a Supercharger, I would think you'd have much more degradation than the scenario I outlined previously.
AlanSubie4Life
Efficiency Obsessed Member
This is normal. Worse than the average given the age and mileage, but normal. Given how little you have driven it, you can do some full discharges, let the car sit at various SoCs, and see whether any of it comes back (it may well bounce back to something in the 290s). But after a year this is generally expected.
Wouldn't worry about it. There are plenty of people with vehicles of similar age at 285 rated miles (11.5% capacity loss).
Again, you can do some road trips and see what happens (maybe claw back 3-4%), but overall this is basically normal. Fundamentally, 11.5% capacity loss after a year is not unusual. Not the norm (median or average), but also not unusual.
Thanks, very helpful. I spoke with a service rep who suggested some of the rated loss is just due to algorithms, so that actual mileage would not have dropped as much. Is this accurate? Or is the physical capacity of battery indeed 11.5% lower?
weird one
my 2018 3p is losing 11-14 miles per day just sitting in my garage.
- the car has 14500miles
- rarely supercharged (maybe 2 dozen times i’ve used in 3 years)
- sentry mode off
- cabin protection on (but temps aren’t high in garage, nor extremely low - the range has been 40 to 80 degrees over that time...i’ve lost less miles in more extreme temperatures over longer durations).
- i started noticing this over the last month or so. it’s possible it’s been longer
- you can hear a little humming coming from the front beneath the car. something is continuously running nonstop. it’s faint but the garage is quiet so you can hear it.
- i’ve received at least one update since it started and it hasn’t been resolved
i took to tesla mt kisco in NY and they said it was because of sentry mode. i told them it wasn’t even on. and even if it was ~13 miles a day lost in normal temps with no activity and nothing to record (nobody goes in the garage) wouldn’t squander that much juice. and further, can’t you tell if it was on or off, what processes are using the juice, etc etc from a diagnostic?
i’m on 4.15.12
i doubt they even did anything. they told me to email them if i see it continue. i parked it with 205 miles at 6pm. i can pretty much guarantee by tomorrow evening it’ll be down below 195.
i guess i’ll track it and email them the degradation report and then see what they say. but i know this isn’t normal.
also, started at 310 miles and now my max is 279. this is expected. i’m not concerned about that. i know there’s a bit of reserve.
but i don’t think losing 1 mile every 2 hours of idle is normal. anyone have any insight on this?
my 2018 3p is losing 11-14 miles per day just sitting in my garage.
- the car has 14500miles
- rarely supercharged (maybe 2 dozen times i’ve used in 3 years)
- sentry mode off
- cabin protection on (but temps aren’t high in garage, nor extremely low - the range has been 40 to 80 degrees over that time...i’ve lost less miles in more extreme temperatures over longer durations).
- i started noticing this over the last month or so. it’s possible it’s been longer
- you can hear a little humming coming from the front beneath the car. something is continuously running nonstop. it’s faint but the garage is quiet so you can hear it.
- i’ve received at least one update since it started and it hasn’t been resolved
i took to tesla mt kisco in NY and they said it was because of sentry mode. i told them it wasn’t even on. and even if it was ~13 miles a day lost in normal temps with no activity and nothing to record (nobody goes in the garage) wouldn’t squander that much juice. and further, can’t you tell if it was on or off, what processes are using the juice, etc etc from a diagnostic?
i’m on 4.15.12
i doubt they even did anything. they told me to email them if i see it continue. i parked it with 205 miles at 6pm. i can pretty much guarantee by tomorrow evening it’ll be down below 195.
i guess i’ll track it and email them the degradation report and then see what they say. but i know this isn’t normal.
also, started at 310 miles and now my max is 279. this is expected. i’m not concerned about that. i know there’s a bit of reserve.
but i don’t think losing 1 mile every 2 hours of idle is normal. anyone have any insight on this?
I can lose 1 mile every 2 hrs in Winter, with nothing on, no sentry, no overheat protection, no smart summon, etc., so it's not unheard of. However, it's not Winter in CT, so the behavior is odd. 4.15.12 Did the problem start after the 4.15.12 update? Maybe a new update will fix the issue. Most are already on 4.18, so you might get updated soon. Have you tried a total reset? Maybe the total reset where you disconnect the HV from under the rear rightside seat, before reconnecting it.
AlanSubie4Life
Efficiency Obsessed Member
It’s not sleeping (contactors not opening). (Sentry would definitely use 2.5kWh per day if it were on, BTW. but it is off.) About 10-15 miles per day is what you get for constant idle mode. (150W or whatever.)
Turn off summon standby (disable summon too) and change your Tesla password, and only provide it to the Tesla app - no other apps.
Temporarily turn off cabin overheat protection (though it likely is not the problem right now).
In any case, the problem is it isn’t sleeping. Just make sure you hear those contactors close. But only when you come to the car should you hear them. They should not be clunking on and off all the time. Just once or twice a day. They make distinctly extremely different noises when opening vs. closing. Opening is much quieter.
As you say, your range loss is completely normal. Plenty of people right around 280 miles in their 2018s.
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AlanSubie4Life
Efficiency Obsessed Member
It’s somewhere around there. I would guess physical capacity is at least 7% lower. It might be 11% lower. Just have to use it and see, though. Nothing to do with algorithms. Estimate could be a bit off but generally it will be picking up the basic trend - so that’s why it says 11.5%.
I can assure you with 99% confidence that your BMS THINKS your battery has lost ~11.5% capacity from the design capacity. This is assuming you have 18” wheels selected and your vehicle started at 322 rated miles according to the EPA. The only unknown is whether the BMS is correct, or confused. Using it in one continuous trip without stopping is the way to determine what you have and really the only relevant metric (for you I’d expect you would find you have about 65kWh available for a full discharge from 100% to 0%).
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thanks @KenC and @AlanSubie4Life
1) I turned off everything and confirmed it was off - the sound persisted.
2) I reset the password and then checked the car and the sound was gone. it was finally asleep.
3) I turned back on the cabin temp control, summon, summon standby (exclude home, work, favorites) and connected bluetooth (left sentry mode off) and the noise/process is running again.
4) I noticed my home is my old address, so I updated my home address, turned off summon beta and standby, and turned back on. the app now recognizes I'm home, and the "come to me button" is no longer present on near top of app..but my summon button beneath is still available if needed.
its only been a few minutes and the sound is still humming.
- the cabin temp is 70F, so its not cabin protection
- the phone key in app /bluetooth is disconnected (because the phone is far enough away in the house)
- sentry mode is off
- the only thing I can think of is the summon running in background despite the changes to my home address, thus the car knowing to exclude standby mode when home, which it seems to know based upon the behavior in point 4 above
ill give it some time and check back in hour or so.
worst case ill turn off summon beta and see if that solves it...but that's not a valid solution considering we spent the 8k at time of purchase to have that future feature, (we updated to Tesla processor when it came out as well)
edit: after some time the noise/process has stopped and the car seems to be sleeping like a baby
thanks again!
1) I turned off everything and confirmed it was off - the sound persisted.
2) I reset the password and then checked the car and the sound was gone. it was finally asleep.
3) I turned back on the cabin temp control, summon, summon standby (exclude home, work, favorites) and connected bluetooth (left sentry mode off) and the noise/process is running again.
4) I noticed my home is my old address, so I updated my home address, turned off summon beta and standby, and turned back on. the app now recognizes I'm home, and the "come to me button" is no longer present on near top of app..but my summon button beneath is still available if needed.
its only been a few minutes and the sound is still humming.
- the cabin temp is 70F, so its not cabin protection
- the phone key in app /bluetooth is disconnected (because the phone is far enough away in the house)
- sentry mode is off
- the only thing I can think of is the summon running in background despite the changes to my home address, thus the car knowing to exclude standby mode when home, which it seems to know based upon the behavior in point 4 above
ill give it some time and check back in hour or so.
worst case ill turn off summon beta and see if that solves it...but that's not a valid solution considering we spent the 8k at time of purchase to have that future feature, (we updated to Tesla processor when it came out as well)
edit: after some time the noise/process has stopped and the car seems to be sleeping like a baby
thanks again!
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AlanSubie4Life
Efficiency Obsessed Member
Great. Sleeping can take some time (as long as 30 minutes, some whirring is perfectly normal), but that’s ok, the main thing is to ensure it sleeps for a long period once it does sleep. Sounds like you found the issue - summon didn’t have your current address so it was in summon standby all the time - contactors have to be kept closed and the car uses about 100W or so (never measured it exactly).
I've averaged 262 Wh/m over 12500 miles in Finland (2 winters over 14 months with a climate here like in S Ontario). I had my climate on 20 deg C all the time whether it was mins 30 or plus 30 C (Finnish temp range winter-summer). I floor it from time to time but mostly drive at average road speeds (the fixed penalty speeding fines are very high). Very happy with that.
Summon standby used to use a fair amount of power too. I turned that off near the release of that feature. I dont use any of the "exclude home / work" settings because (for example) people have reported the car not locking at home etc. I just dont have a lot of confidence in the geofencing of those features.
Try turning off summon standby all together, and see.
AlanSubie4Life
Efficiency Obsessed Member
Great - final comment on this as vampire is only tangentially related here I suppose - as I've said elsewhere, it's perfectly normal for a perfectly sleeping car to be awake and whirring (I think this is a cooling pump for the electronics though I am not sure) for about 1-2 hours per day. This is in fact required, since during that idle time the car must top off the 12V battery from the HV battery via the DC-DC. In sleep the 12V battery runs everything, at a load of around 10W (very approximate) - so that requires about 1-2 hours of recharging each day (when the 12V battery voltage drops to below about 12.8V that triggers a wake-up event). (The 12V battery has a capacity of something like 0.6kWh.)
That perfectly sleeping car will use a couple miles a day or so. The first day is nearly always worse (due to rebalancing or whatever, and other BMS readjustments) so you should ignore that. Also ignore any days when you're near the car.
My situation may be similar to yours.
2019 M3 LR AWD
Max car will charge is 284 miles (100%). As you said, there is a reserve. I ran my car down to 0%. I drove for another 14 miles before it actaully shut down and had it towed.
However, the max miles i can ever get with my tesla m3 is 220 - 240 miles from a full charge - NEVER the 280 (stated) or expected 310 miles.
Tesla customer service is worst than a used car dealership customer service. You bring this up to them and they will brush you off.
I hate seeing people repeat this junk, because it's going to cause some people to get bitten by relying on it..
No, there isn't always a reserve. The cars aren't necessarily meant to have any reserve. Sometimes, on some people's cars, the battery calculation is off enough in a certain direction that there DOES happen to be some extra energy left after the display goes to 0. That is an accident people sometimes benefit from. But stop telling people it is supposed to be there. Plenty of people have found that the cars will shut off within that last 2 or 3 rated miles above or below 0 on the display.
AlanSubie4Life
Efficiency Obsessed Member
I will not quibble with your main point: don't attempt to drive below 0 miles! I would never try to do that (unless I'm prepared to tow my car), and unless in a real bind, I would attempt to arrive at a charger above 4-5% SoC.
However, my understanding is the buffer and how it is indicated may have changed over time? (Not sure the history.) Anyway, that could explain some of the shutdowns near 0 rated miles that have occurred in the past - I have no details on those, so no idea.
As a counterpoint - as you know, Tesla themselves claim that you need to be able to use the buffer, and not counting it isn't fair. Testing Tesla's Range Anxiety: Tesla Model Y, Model 3, VW ID.4, Ford Mach-E | Edmunds
"Tesla argued that even when the indicated range hits zero, there's still a safety buffer. The engineers reckoned that if you add this buffer, the distance measured to when the battery is spent, their cars would match the EPA results."
They got 10 miles after zero in a Model Y (that was the minimum of the Tesla vehicles they tested - they got 22 miles out of the LR but this value is going to vary a huge amount from vehicle to vehicle). And using that extra range is part of the EPA test result.
Your other point: the estimation could be off; yes, it's going to be unpredictable and if you don't drive with an egg between your foot and the accelerator, you could easily sag the voltage enough to cause an automatic shutdown. And it might shut down regardless of what you do. Battery gets a little chilly, steep hill, etc. YMMV. The EPA test where they extract this energy is in most cases done at room temperature, benign conditions, under a constant very low load (one which gets ~350 (!!!) road miles or so out of the battery). (SS cycle is used to deplete the battery - they get about 210Wh/mi or so, depending on the vehicle.)
So I'd say the (recent) cars [Model 3, Model Y] are designed to have a reserve (it's not an accident), but you shouldn't ever attempt to use it. If you're in a bind and you're using it...don't expect much...or anything at all...
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Ah yeah, I realize I am talking about what is now some very outdated stuff with the Model S. They originally had them built with a buffer built in, and it was an update around the time in the 4.X versions that they very specifically and intentionally re-allocated the energy into the usable part and DELETED that buffer completely. People who absolutely knew (eyeroll) that their cars had this below 0 buffer and knew (eyeroll) exactly how much it was started getting burned over and over and over as the cars shut down right at 0. (pretty impressive accuracy, actually)
"the cars" Which cars? I do recall now Tesla saying some of those other things you are talking about, that since they Model 3 and Y, they seemed to have changed this yet again to go back to the old method of trying to have a below 0 buffer again, so I guess my long time history is working against me here, as it used to have it and then didn't for quite a while and now probably does again.
AlanSubie4Life
Efficiency Obsessed Member
Model 3 and Model Y, for sure. No idea on the others. You can probably tell how it works on any given vehicle by both looking at the EPA data and closely examining how the energy screen behaves (could also look at what trip meter rate do miles tick off relative to the constant, specifically). If it's consistent with the Model 3/Y then the energy screen & buffer should work the same way. (I believe that the % allocated to the buffer is DIFFERENT for Model S, though - I think it's a larger % (larger than 4.5%) - but this info is over a year old.)
But you shouldn't use the buffer even if it's there.
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ahh...the 280 isn't guaranteed. its the way you drive it, just like with ICE.
1) never drive it to 0, I don't think that's a good idea. (why would anyone do this unless it happened by mistake?) - keep it between 20-80 is the general rule for daily driving, at least what I've been told by most. but at minimum, try to charge it by the time you get to 10-15%
2) if I'm in sport mode and I drive like I stole it, sure I'm not getting the 300 miles.
3) in regular or chill mode if I drive 60-70mph then ill get close to what the car estimates
just like if I drive my ICE vehicle at 90mph down the highway the mpg drops from estimated 18-21 to 12-14mpg...
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Thanks! I did read through that one already
What's the consensus on max % charge for optimal battery life? The manual is surprising lacking in that department.Similar threads
