Valet Charging

[Breddie]

Hello,

I have a 2021 M3 SR

I am currently on vacation and the hotel I’m staying in charges your vehicle for you

since I traveled with the car, I set the charging at 100% before I left and never decreased it when I got to hotel. The car is now 100% charged and still at valet..

will this be an issue with battery degradation or anything like that?

ty!

 

[ATPMSD]

Yes, leaving the car at 100% when not needed is bad for the battery. Use your app to lower the percentage to 80% or less.

 

[Sophias_dad]

Hello,

I have a 2021 M3 SR

I am currently on vacation and the hotel I’m staying in charges your vehicle for you

since I traveled with the car, I set the charging at 100% before I left and never decreased it when I got to hotel. The car is now 100% charged and still at valet..

will this be an issue with battery degradation or anything like that?

ty!

It would be good of you to claim the car and drive it down to 95% or less.

I happened to accidentally do this a while back and didn't want to go for a drive.. If the car is unplugged, you can use the climate control to drain the battery a bit. Seat heaters on low while the AC is set to 68, or whatever works given your local weather conditions.

 

[ATPMSD]

After lowering the percentage you can also just turn on Sentry mode, this will consume about 5-6 kW / day.

 

[AZAV8R]

I get it that regularly keeping a lithium battery at 100% is not a good idea, but to intentionally bleed it down to 95% due to unintentional charging seems a bit of an over-reaction.

Anyone? Anyone?

 

[Sophias_dad]

I get it that regularly keeping a lithium battery at 100% is not a good idea, but to intentionally bleed it down to 95% due to unintentional charging seems a bit of an over-reaction.

Anyone? Anyone?

What are the pros/cons of each approach....

Do nothing. It sits at 100% for a week or at least until it bleeds down to 95%. OP comes back here in a few weeks and says "Waaaah... my 325 mile 100% is only 315 miles now.... this car sucks.... should I call Tesla?" (That's a bit sarcastic, I realize).. the numbers may be a bit off, but even so, we can probably assume at least SOME of that lost range is due to the 100%. I don't have hard numbers for the losses, and it probably depends on the car but such losses are probably permanent, like for-the-life-of-the-car.


Bleed off some excess as soon as reasonably possible. Assuming OP is paying for the charging(which is not at all clear), 5% of an 80kwh battery is 4kwh. So, if it were at my home, that's ONE whole dollar of electricity being flushed. If it were in AZ, thats HALF a dollar of electricity or less. Is it not worth the peace of mind to not permanently decrease the capacity of OP's new 3 ? OP also has a SR 3, so that 80 is probably more like 55kwh, so the real numbers are more like $0.75 and $0.37.


Side note... I'm not sure of the battery chemistry these days on an SR, but I understand some of the newest packs are of a new variety that doesn't mind getting full-charged repeatedly.

 

[cwerdna]

After lowering the percentage you can also just turn on Sentry mode, this will consume about 5-6 kW / day.

You mean 5 to 6 kWh per day?

 

[ATPMSD]

You mean 5 to 6 kWh per day?

Yeah, always messing this up. kW is the rate of consumption and kWh is capacity, so kWh is correct.

 

[Trekker_]

I get it that regularly keeping a lithium battery at 100% is not a good idea, but to intentionally bleed it down to 95% due to unintentional charging seems a bit of an over-reaction.

Anyone? Anyone?

I'm with you. If lithium batteries were that sensitive to 100% charge, all of our phones wouldn't even turn on anymore with 100% charges every night. People are too scared about this

 

[Sophias_dad]

I'm with you. If lithium batteries were that sensitive to 100% charge, all of our phones wouldn't even turn on anymore with 100% charges every night. People are too scared about this

Are you sure the same people who brought you the deliberately slowing down iPhones didn't also build in 10-20% headroom on their reported battery capacity, so the '100%' reported charge is really only 90% of its capacity?

This, so they don't get users who say "Waaah, my battery only lasts 95% as long after three months, should I call Apple/Samsung/LG right away?" Does any phone user even notice a 5-10% capacity loss, or do they notice and just accept that after two or three years they'll get a new phone anyway?

 

[Rocky_H]

I'm with you. If lithium batteries were that sensitive to 100% charge, all of our phones wouldn't even turn on anymore with 100% charges every night. People are too scared about this

This is the very thing that is the main driver of the 2 year phone upgrade cycle. People do that, treating their batteries like $&^@ and then they are severely degraded with short battery life in about two years.

 

[Trekker_]

This is the very thing that is the main driver of the 2 year phone upgrade cycle. People do that, treating their batteries like $&^@ and then they are severely degraded with short battery life in about two years.

My phone is 2 years old, gets treated like crap, and my battery still lasts more than 24 hours of me running a business off of it. If your phone is low all the time its probably because you never let it die. There is no way for a BMS to calibrate if you don't use the full range. I don't plug my phone in until its at 1% or dead about 60% of the time. Also don't get me wrong, I'm not saying charge your car to 100% every day, but man, letting your car go to 100% for a few days on vacation isn't gonna hurt it. If you think that is a big deal, you really should not own an electric car my guy.

EDIT:
Didn't know this forum censored casual swear words. My B

 

[Trekker_]

Are you sure the same people who brought you the deliberately slowing down iPhones didn't also build in 10-20% headroom on their reported battery capacity, so the '100%' reported charge is really only 90% of its capacity?

This, so they don't get users who say "Waaah, my battery only lasts 95% as long after three months, should I call Apple/Samsung/LG right away?" Does any phone user even notice a 5-10% capacity loss, or do they notice and just accept that after two or three years they'll get a new phone anyway?

Yes I'm sure. 2 reasons. You can open your phone and see the rated capacity on the battery. Secondly, battery size is a huge selling point on phones, they are not going to underrate phones. Battery degradation is a thing, seller of phones are not responsible. Is degradation as bad as people here make it out to be? no, not at all.

 

[jjrandorin]

Most modern phones (including iPhones) also limit charging to 100% whether the user knows that actively or not (on an iphone its Settings -- Battery --Battery Health -- Optimized battery charging (which is ON on my iPhone, and I did not actively turn it on).

The description of "optimized battery charging" on an iPhone reads this (exactly, word for word)

"To reduce battery aging, iPhone learns from your daily charging routine so it can wait to finish charging past 80% until you need to use it"

So, yes, even phones try to limit battery degradation by not sitting at 100% all the time.

Where I work, we are having an issue with HP laptops and the battery swelling. HP claims that this is because "due to covid, people are using the laptops with them being plugged in all the time, vs cycling the battery. They should not sit at 100% all the time. We have released a firmware update for these HP laptops to prevent them from sitting at 100%".

So, yes, even laptops have issues with batteries sitting at 100%.

Of course, everyone is free to use their devices how they want as long as it doesnt impact anyone else, and someone leaving their car at 100% doesnt impact anyone else so @Trekker_ , if you dont think this is a thing, feel free to leave it at 100%.

 

[Trekker_]

Most modern phones (including iPhones) also limit charging to 100% whether the user knows that actively or not (on an iphone its Settings -- Battery --Battery Health -- Optimized battery charging (which is ON on my iPhone, and I did not actively turn it on).

The description of "optimized battery charging" on an iPhone reads this (exactly, word for word)

"To reduce battery aging, iPhone learns from your daily charging routine so it can wait to finish charging past 80% until you need to use it"

So, yes, even phones try to limit battery degradation by not sitting at 100% all the time.

Where I work, we are having an issue with HP laptops and the battery swelling. HP claims that this is because "due to covid, people are using the laptops with them being plugged in all the time, vs cycling the battery. They should not sit at 100% all the time. We have released a firmware update for these HP laptops to prevent them from sitting at 100%".

So, yes, even laptops have issues with batteries sitting at 100%.

Of course, everyone is free to use their devices how they want as long as it doesnt impact anyone else, and someone leaving their car at 100% doesnt impact anyone else so @Trekker_ , if you dont think this is a thing, feel free to leave it at 100%.

Everyone seems to forget we are talking about a few days at 100%????? A few days does not make a lick of difference. Let me repeat... A FEW DAYS. I never said all the time at 100% wouldn't degrade it faster

 

[jjrandorin]

Everyone seems to forget we are talking about a few days at 100%????? A few days does not make a lick of difference. Let me repeat... A FEW DAYS. I never said all the time at 100% wouldn't degrade it faster

Im not sure why you disagreed with my post, when all I did was provide verified information that, yes, phones and laptops also advise not to charge to 100% ,and said "use your device how you want to".

 

[Trekker_]

Im not sure why you disagreed with my post, when all I did was provide verified information that, yes, phones and laptops also advise not to charge to 100% ,and said "use your device how you want to".

I disagree with pushing the idea that sitting at 100% for a few days is absolutely detrimental to a battery. Are you really whining that I disagreed on your post? Sorry I hurt your internet points I guess?

 

[jjrandorin]

I disagree with pushing the idea that sitting at 100% for a few days is absolutely detrimental to a battery. Are you really whining that I disagreed on your post? Sorry I hurt your internet points I guess?

I dont care about "internet points" but tend to forget that some people use disagrees when they dont like something, even if its factual information. I dont recall anyone saying that it would be a huge detriment to leave it at 100%, but stating that its "none" is not correct either. We know for 100% fact that it has an impact. We dont know how much impact, for how long.

shrug.. like I said, you do you.

On a side note, this is now another in a very long line of "battery degradation" threads, and in the model 3 section, that discussion is here:

Range Loss Over Time, What Can Be Expected, Efficiency, How to Maintain Battery Health

I just spent about an hour reading the entire document lol (nerd). My takeaway was there was a ton of data in there but out of the things you can control you should basically just keep it between 20 and 80% and you’ll keep 90%+ capacity over a long period of time. If you really don’t drive a lot...

teslamotorsclub.com

So, I am going to request that further discussion on the topic of battery degradation (by me or others) be moved to that thread.

 

[Trekker_]

I dont care about "internet points" but tend to forget that some people use disagrees when they dont like something, even if its factual information. I dont recall anyone saying that it would be a huge detriment to leave it at 100%, but stating that its "none" is not correct either. We know for 100% fact that it has an impact. We dont know how much impact, for how long.

shrug.. like I said, you do you.

On a side note, this is now another in a very long line of "battery degradation" threads, and in the model 3 section, that discussion is here:

Range Loss Over Time, What Can Be Expected, Efficiency, How to Maintain Battery Health

I just spent about an hour reading the entire document lol (nerd). My takeaway was there was a ton of data in there but out of the things you can control you should basically just keep it between 20 and 80% and you’ll keep 90%+ capacity over a long period of time. If you really don’t drive a lot...

teslamotorsclub.com

So, I am going to request that further discussion on the topic of battery degradation (by me or others) be moved to that thread.

I didnt use disagree because I dislike it. I disagree with you so I used disagree. And you do care if you pointed it out lol