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Real damage from full charge?

Real damage from full charge?

It's hard for me to believe Tesla would allow you to hurt the battery by charging it full. Has there been any concrete data that shows losses or damage when comparing a semi full vs always full Tesla? For a semi newb What exactly happens. What should and shouldn't you do?

Thanks

rxlawdude | 06. August 2017

A plugged in Tesla is a happy Tesla. No worries.

eleestein | 06. August 2017

Lithium Ion Batteries will degrade faster if they are consistently charged above 80% or depleted lower than 20%. If you fully charge your Tesla every now and then to go on a trip or on a day that you know you will do an excessive amount of driving, it will do little to no harm to the battery. Set your charging to the recommended level you will see on the Tesla Monitor. Don't drive your Tesla down to near 0 of range. I wouldn't even let it get down to 20 miles of range.

Liba | 06. August 2017

I understand the theory. Just wondering if there has been any actual data for comparison. Thanks

Steam613 | 06. August 2017

It's default is to charge to only 80%. There is a special trip mode that allows it to charge to 100%. By charging mostly at home (not Superchargers) and only charging 100% on rare occasion the battery life is estimated 250K miles by Teslanomics video blog.

noleaf4me | 06. August 2017

Steam - any idea if the 310 miles is only at the 80%?

Liba | 06. August 2017

What damage or degradation would you predict if someone used a supercharger and charged full daily?

greg | 06. August 2017

If you do exactly as Tesloop does with your daily supercharging to 100%, then you'll probably have the same experience they did i.e. a good one].

Exactly how they charge:

"For your daily driver, you don’t fully charge unless you’re doing a long trip. We’re doing a long trip every day. We save, like, three minutes in charging in Barstow if we fully charge beforehand. We decided that we’re gonna suck it up, fully charge, and let it degrade. We figured that if it degraded enough, we could take it off a Vegas route and put it on a local Orange County route."

So the danger with a Tesla EV is charging it up to 100% (full) then not driving it while the battery is too full (i.e. close to 100% full) to get the charge back down below the 80-90% level before you park it up for the night.

So if you insist on daily supercharging to 100%, **do it at the start of the trip** like these guys do not at the end.
Otherwise just charge it to 80% at the SC and don't run it below 20% on the bottom end very often.

And keep it plugged in at home if you can, to maintain that 20-80% charge level as much as possible - that makes for a happy battery.

Liba | 06. August 2017

Good info. Thanks

SUN 2 DRV | 06. August 2017

The important issue seems to be the TIME SPENT in a high state of charge, not just the fact that you fully charged it. Most Full Charging is done right before leaving on a long trip, and so minimal time typically spent in the full charge state thus minimal degradation.

Charge to 100% whenever you need that range and time it to finish around your departure time.

Just don't leave it set to 100% charge and plugged permanently without driving it and you'll be fine.

Darkon | 06. August 2017

This topic seems to be pushing me towards the larger battery since it's typical range (when a longer trip isn't planned in advance) is closer to 80% of the max range...or ~250 miles (vs 180 with the smaller battery). I think 250 miles w/onhaving to plan in advance will be fine for me, but 180 would be more likely to be an issue for me based on my driving habits.

greg | 06. August 2017

@SUN2DRV
"Charge to 100% whenever you need that range and time it to finish around your departure time."

If you're charging at home can you tell the car [via the Tesla App? or via the central display] what time you expect to need the car ready by, so it can get it to your selected 100% charged point **just before** that selected departure time to minimise the time spent sitting at 100%?

Shock | 06. August 2017

I hope you realize what 6% range in 200k means. After reading in great detail about the unmitigated debacle that has been the Leaf's "missing bars", 6% in 200k is a monumental achievement.

Steam613 | 06. August 2017

310 miles is full charge

JayInJapan | 06. August 2017

At home, I use the amp setting to time my charges.

Before a long trip, I usually charge to 90% overnight. Then about an hour and a half before I leave, I move the slider to %100. The battery is charged, at the proper temperature, and the car is ready to go.

JayInJapan | 06. August 2017

Power users will have read and understood everything at @TT'S site:

https://teslatap.com/articles/owners+manual+companion

MarylandS85 | 06. August 2017

+1 JayInJapan
That’s what I’ve always done. In the hour I need to get my family and me ready and load the S, I’m up to 99% or 100%.

Meanwhile, yes, charging to 80% routinely gets you 176 rated miles on the 220 mile battery. In cold weather, that could translate to 140 miles. For anyone hesitating, I suggest you track how much you drive. Don’t just count your daily round-trip commute. Consider side trips and random outings. What if you have to go to work and back on a Friday, then drive to a friend’s house an hour away? Ask yourself what the worst-case scenario is. Then consider whether you will have that need often enough to consider the $9,000 long range battery. Consider also whether there will be Superchargers on the common routes you would take (there probably will be). Refer to the interactive Supercharger map, including the future planned sites.

Or just charge your 220 mile Model 3 to 90% (or even higher) everyday. That’s not the end of the world. You could minimize the damage by programming the car to start charging so that it finishes right as you get in to drive to work. As others have noted, unless you leave it at a high state of charge for extended periods, the damage is minimal. This topic has been covered on numerous other threads in Model S and X forums.

Let me just say that if you have never driven an electric vehicle, 220 miles is a lot of range. For the vast majority of you, the 310 mile range will be unnecessary. Don’t let paranoia make you waste $9k.

Captain_Zap | 06. August 2017

+1 JayInJapan

That is our protocol too.

cquail | 07. August 2017

I can only offer my personal experience. I have had an S85D since April 2015. I have 83K+ miles on the car. I always charge to 90%. I charge to 100% when ever I think I need the extra miles. I have done this many times. When the car was new, rated range was 270 miles on a 100% charge. Now it is 263. The vast majority of my charging has been at Superchargers. When I charge to 100%, I always plan to drive the car within the next hour.

georgehawley.fl.us | 07. August 2017

The Model X owner's manual says nothing about charging to 100% pro or con for example.
I did see an alert on my dash display when I set the charge limit to 100% one time. I don't remember the exact wording but it was something meant to discourage charging to 100% as a regular practice.

Charging to 100% will not "damage" a Tesla battery pack. If that were a possible outcome, the software would be designed to prevent doing it.

Less understood is the slow degradation that lithium-ion batteries experience over time. The rated miles achieved for a given percentage charged shown on the car's display is only indirect evidence of possible long term degradation under normal circumstances. By all accounts, owner observation of rated miles and laboratory observations of battery cell behavior, the Panasonic/Tesla cells degrade very slowly with depth of charge, environment, rate of charge, number of discharge-charge cycles, depth of discharge, and rate of discharge all possibly playing a role in battery aging.
Bottom line: not worth worrying about. It doesn't seem to matter much how you treat your Tesla battery unless you run it dry.

SP_H | 07. August 2017

So best practice is to charge when it is close to 20% and stop at 80%. So if my day to day usage is different I can just plug it in when it's 30%, 40% or 50%?

carlk | 07. August 2017

Do like what JayInJapan said. Don't let the car to sit at 100% for a long period of time there will not be a problem. It's not going to destroy the battery even if you did but why take the risk?

SP_H the best practice is to plug it in whenever the car is at home and set the charge limit to around 80%. There is no difference in battery life between charging to 80% or 50%, which is pretty much nil. You will develop a good habit and not to have a surprise to discover that the battery is not charged enough when you are ready to go.

SP_H | 07. August 2017

@carlk
Thank you, that makes me feel better. Now I know I can plug it in whenever. I just need to make sure the car doesn't go above 80% or below 20% if possible. :)

Daryl | 07. August 2017

There is a lot of discussion about the default maximum charge being 80% of a full battery, but little discussion of the minimum. Will the car let you drive until the battery is empty, or does it stop with something left, and require you to override that safety feature? When it says you have 20 miles of range left, is that until the battery is totally depleted, or does that leave a buffer?

With my Volt, it always keeps the charge between about 20% and 80%, but with a Volt the motor just comes on at 20%. You don't have the option or need to further discharge the battery. I think that's why Volt batteries seem to last so long, that and a very efficient liquid battery cooling system. In 5 years and 40,000 miles in the Arizona heat, I haven't seen any decrease in range.

CraigW | 07. August 2017

+1 JayInJapan

This is like the range anxiety issue. There is practically no way to make a non-Tesla owner stop worrying about these things. The only cure is to buy the darn car and try to drive it into the ground.

Two Tesla, 100,000 miles and very little battery loss. The Tesloop link says it all. I have gotten down to 0RM twice and below 10RM on numerous occasions.

Again, don't leave your car at a low battery level. If you car is below 50RM don't leave it that way overnight. Don't leave your Tesla fully charged for long. Other than those two rules, these batteries are real soldiers.

CraigW | 07. August 2017

Daryl,
There is a reserve below 0RM, but none of us knows what it is. Just know that car won't stop when you reach 0RM.

Rocky_H | 07. August 2017

@CraigW, NO! Stop spreading that myth. Sometimes a car may accidentally be able to drive below 0 just because of the measurement being inaccurate, but there IS NOT an intentional driving reserve below 0. Stop telling people that. There have been plenty of people who have had their cars shut down right at 0 and even with a few miles still remaining on the display.

https://teslamotorsclub.com/tmc/threads/has-your-car-shut-down-before-it...

Frank99 | 07. August 2017

No damage will come of discharging the battery down to what Tesla calls 0. This probably corresponds with a battery voltage of 3.0-3.3 Volts, which is considered fully discharged. If Tesla allowed it, you could discharge all the way down to 0 V, but there's only a tiny fraction of battery capacity left at 3.0V, and irreversible chemical reactions start to occur as you get down to 0V.
That said, I wouldn't leave the battery at 0RM for weeks at a time. The normal operations of the car when parked, as well as self-discharge in the cells, could start dropping the voltage down towards zero and start causing issues. I'm sure Tesla shuts everything down with the voltage gets too low - but they can't do anything about self-discharge.
So, IMHO, feel free to get home with 0RM left (if you're a gambler), but plug it in when you get there.

Redmiata98 | 07. August 2017

The max daily charge to is 90% not 80%, look at your touchoad and you can see it!

rxlawdude | 07. August 2017

Bottom line: Plug your Tesla in at night (if you have the infrastructure), keep the charge slider routinely at or less than 90%, and don't routinely drive below 5%. Road trips needing 100%, not a problem, but charge immediately prior to departing rather than having it sit at 100% for prolonged periods.

No one can definitively say what "prolonged periods" means, but the consensus is a matter of hours.

jordanrichard | 07. August 2017

Redmiata98 +1. I think the only people who should be answering any questions about charging techniques/tips/concerns should be owners.

No one ever said 80% is the "default" daily charging limit. It is 90%. If Tesla thought it was 80%, they would have adjusted it. They did that for the default full open % for the sunroof. It used to be something like 80% (can't remember), but I do know that with one of the software updates, they changed it to 75%. So clearly there was something that made them change that as they surely would have done with the Daily Charging limit on the charging screen.

100% is fine, as long as you don't let it sit at 100%. Also as ahead up to any future owners, when you charge to 100%, you will have no regen at all because there is no place for the charge to go. So you will be relaying on your brakes. If you charge to 90%, you will have full regen.

COrich | 07. August 2017

The default setting on a new Tesla is 90% from the factory. This is the upper end of the "daily" charging profile. Above that is labeled "trip". Daily charging at anywhere from 50-90% is considered daily by Tesla and should cause no problems with the battery. Note that this all assumes regular charging using either the UMC or the Tesla wall connector.

There is a different issue with charging daily with a supercharger. Supercharging can stress the battery cells more due to the much higher power applied to the cells to charge at the higher rate. Eventually the charging profile will change to be a bit slower to prevent damage to the battery. Remember that the original concept of the superchargers was to provide rapid charging for trips. Daily charging was supposed to be done at home.

The use model is gradually changing so we might see some recommendation changes for supercharger usage for daily charging.

Haggy | 07. August 2017

Tesla isn't saying that charging to 100% will damage your battery. They are saying that charging to 90% regularly won't harm the battery. They know which scenarios are perfectly safe. There are others that may or may not be, but it becomes too hard to have hard and fast rules. There are people who charge to 100% fairly regularly right before trips and have had no issues. In theory, charging to 100%, leaving the car in the garage, and constantly topping off the charge to 100% would not be good for the battery. Tesla isn't going to say it's fine to charge to 100% whenever you want because it's easier to say what's known to be safe and to let drivers go beyond that on occasion, which will most likely not cause any problems. It would simply be too tough to draw a precise line.

Chances are that if you charge to 100% several times a week, and leave right after the car gets to 100%, you won't see extra degradation. But that's not an official recommendation nor would there be a reason for Tesla to try to come up with a long list of scenarios and say which ones might or might not be risky when they can list ones that are always safe and will satisfy most driving needs.

It's not as if I've ever found myself low on miles because I charged to 90% on a non-road trip day and charging to 100% every day would have prevented it.

teslamotorfaq.com | 07. August 2017

I have the software limit 60, when I email Tesla service they reply it's ok to charge to 100% but Tesla still recommend charging to % for your daily driving. So without knowing what's the actual capacity of the M3 battery it's really hard to tell.

borne.by.wind | 07. August 2017

Has anyone who charges to 100% SoC daily had a warranty issue if the battery has degraded? Tesla would have access to the SoC data for all of our vehicles.

CraigW | 07. August 2017

Rocky_H,
Sorry, but I had an early S60 and it went to 0 RM on a couple of occasions - I was within 3 miles of and owner's home in the 1st cast and within 2 miles of Harris Ranch in the other - without any problem. I DO NOT recommend this to anyone. I was trying to hypermile it in the 2nd case and a slow, continuous upgrade surprised me in the 1st case. The S60 had 207 miles max out of the factory and 60,000 miles later it had degraded to 203 miles, so I was very happy.

However, I have gotten well below 20RM on any number of occasions. The key here is that I was traveling. When at home, I never let the battery get that low unless I am trying to run it down to do a max charge and reset all the computations - recommended once/twice a year if you feel your battery is not giving you correct figures.

The point of all this is that people get really scared their battery is going to fail if they get to 10RM. This is simply not the case. That said, do not leave the battery in an extremely high or low state.

Rocky_H | 08. August 2017

@CraigW, Quote: "Sorry, but I had an early S60 and it went to 0 RM on a couple of occasions"

Right, probably very early, which is what gave you this idea. Long ago, there did USED to be some driving capacity below 0. I can't find the thread for it now, but there was a specific firmware update version that REMOVED that driving reserve. Therefore, it is very irresponsible for you to tell people using the present tense that there is a driving reserve below 0 and that the car will not shut off when it reaches 0. That is just not true, and it's terrible to convince people that it is.

Did you read that thread I linked you to? There were many people who told of how the car does shut off right there within a mile or two of 0, some even with 2 or 3 positive miles still remaining on the display. We need to let people know that 0 really does mean 0 now, and the car very likely will shut off there, so you're risking it if you get down into those single digits.

Shygar | 08. August 2017

Hopefully this isn't too much of a tangent, but what's the recommendation for charging when you need to leave the car for a month?

Mozart | 08. August 2017

Leave the car plugged-in and set charging level to 60%

Frank99 | 08. August 2017

Good, solid recommendation right there.

If you can't leave it plugged in, then leave it charged at 50-80%. You'll lose a few percent to background power usage in the car before it goes into deep sleep, leaving it in the perfect long-term storage range.

That said, leaving it at just about any state of charge (except, perhaps, 0%) won't cause any issues. Tesla is very good about protecting the battery. However, if you leave it very low, you may come back to a car that won't do anything until you charge it.

LA-Fohlen | 08. August 2017

@CraigW - Harris Ranch? Wow, that stinks.

Shygar | 08. August 2017

Awesome, thanks!

SUN 2 DRV | 08. August 2017

"Harris Ranch? Wow, that stinks."

True, (depending on the time of year and wind direction) ... until you get inside the restaurant and smell the delicious steaks.

ReD eXiLe ms us | 08. August 2017

Haggy is correct.

Quoted for TRUTH:

Haggy | August 7, 2017
Tesla isn't saying that charging to 100% will damage your battery. They are saying that charging to 90% regularly won't harm the battery. They know which scenarios are perfectly safe. There are others that may or may not be, but it becomes too hard to have hard and fast rules. There are people who charge to 100% fairly regularly right before trips and have had no issues. In theory, charging to 100%, leaving the car in the garage, and constantly topping off the charge to 100% would not be good for the battery. Tesla isn't going to say it's fine to charge to 100% whenever you want because it's easier to say what's known to be safe and to let drivers go beyond that on occasion, which will most likely not cause any problems. It would simply be too tough to draw a precise line.

Chances are that if you charge to 100% several times a week, and leave right after the car gets to 100%, you won't see extra degradation. But that's not an official recommendation nor would there be a reason for Tesla to try to come up with a long list of scenarios and say which ones might or might not be risky when they can list ones that are always safe and will satisfy most driving needs.

It's not as if I've ever found myself low on miles because I charged to 90% on a non-road trip day and charging to 100% every day would have prevented it.

georgehawley.fl.us | 08. August 2017

Where does Tesla "say" you should charge to 90%? Are you referring to the dashed line across the battery icon on the charging window? The owner's manual says nothing about this that I have found. Maybe I missed something.

Most of the above "best practice" is unsupported by any Tesla publication that I know of. Aside from discharging the battery to the point of turning it into a brick or operate it outside the specified temperature
I kits, there is nothing you can do to the battery pack that demonstrably causes any more or less degradation. If it makes you feel good to operate mainly between 20% and 90% as I do, then do it. YMMV.

Supercharger myth: Supercharging puts more stress on the battery cells and increases degradation. Actually, in terms of peak current/cell, launching the car discharges the cells at currents up to 5 times the maximum SC charging current, albeit for only a few seconds, but that is stress. Actually, according to Dr. Jeff Dahn who works as a battery consultant to Tesla, the high charge rate when Supercharging may diminish degradation by not allowing enough time for unwanted reactions to occur that produce degrading deposits on the anode. Go figure.

georgehawley.fl.us | 08. August 2017

Temperature limits...

CraigW | 09. August 2017

georgehawley.fl.us +1

I have talked to Tesla service people who say the battery works best between 20% - 80%.

I just set my battery to 80%, because that is easy and it serves all but my most extreme needs. When I leave home on a trip I normally don't charge to 100%, but save that for a stop at a supercharger where range might be a factor. Since it takes so much longer to charge that last 20% at superchargers, this means I rarely try to charge my car to 100% any more.

The real time to charge to 100% is if you are leaving Gallup, NM and heading into central Colorado or south into central New Mexico, where there are no superchargers.

ken | 09. August 2017

i have the real live data for you, my MX charge to 100% daily, I deplete to zero and definitely below 10% all the time. currently 65k miles and lost 7% of charge.

jordanrichard | 09. August 2017

ken, I would suggest you change your charging practices, if possible.

Mar. 2014 MS85, 87,000 miles, daily charge 90%, very rarely get below 10%, a few times below 20% and I only have a 2.5% loss. A 90% charge has been getting me a consistent 232 miles for the past year or so.

CraigW | 09. August 2017

ken,
IMO, you could reduce your battery loss a little bit - and I would modify your practice - but you point is well taken. These batteries are pretty sturdy things and you can do a lot to abuse them and they still come back for more.

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