Losing 2% charge over night

[flixden]

Parked in garage around 5:00pm last night with 39% SOC, plugged in and set for a 10:00 departure the next morning, charge limit set to 50%. Sentry mode is off. Checked last night at 10:00pm, 38% left. Just now, at 6:30, it's down do 37%.
Seems excessive to me to lose 2% in 13 hours with Sentry off.
What could be causing this?
I searched, but could not really find an answer that applies to me.

 

[flixden]

To add: i just checked the garage temperature, it was between 18 and 21 degrees C (64 - 70 degree F) for the period of time in question.

 

[GtiMart]

2% is not significant enough to come to any clear conclusion. It could very well be BMS adjustment, or a slight change in battery temperature.

 

[flixden]

Thanks! I will keep on monitoring what happens.

 

[GtiMart]

If you monitor with the mobile app... each time you open the app it will wake the car up. Just this monitoring will consume more energy...

 

[ewoodrick]

What about Cabin overheat?

 

[jjrandorin]

This thread is the same thing, it just happens to be 2% gain.

I charge my battery to 80% last night and woke up this morning. It was at 82. Does that mean my battery is getting stronger ???

charge my battery to 80% last night and woke up this morning. It was at 82. Does that mean my battery is getting stronger ???

teslamotorsclub.com

They both mean the same thing (basically "nothing").

 

[flixden]

What about Cabin overheat?

Cabin overheat is set to 40C, but I posted my garage temp graph, it never exceeded 21C. So I am sure that overheat protection hasn't kicked in.

 

[jcanoe]

If your Tesla Model Y is new and you regularly maintain the battery state of charge between 40% and 50% the battery management system (BMS) does not have much data to work with when determining the state of the battery. Periodically charge to 95% or higher and drive (over multiple days if needed) until the battery state of charge is at or below 20%. At least some of the time park with Sentry mode set to be off so that the BMS can perform the open cell voltage measurement.

 

[flixden]

This thread is the same thing, it just happens to be 2% gain.

I charge my battery to 80% last night and woke up this morning. It was at 82. Does that mean my battery is getting stronger ???

charge my battery to 80% last night and woke up this morning. It was at 82. Does that mean my battery is getting stronger ???

teslamotorsclub.com

They both mean the same thing (basically "nothing").

Yeah, need to watch it more, I guess.

 

[flixden]

If you monitor with the mobile app... each time you open the app it will wake the car up. Just this monitoring will consume more energy...

2KWh though is a lot of energy, only monitored twice.

 

[GtiMart]

2% is closer to 1.5-1.6kWh, your battery is not 100kWh, and with rounding we don't exactly know... When the car is awake it consumes 200-250w constantly whereas it only consumes 20w or less asleep. Every time you wake the car up, it might stay awake for 30 minutes, an hour... No one knows the exact logic but it's not just on-off in an instant. The best is to leave it alone, and not fret small changes like this since we cannot even tell with certainty if it is real energy consumption or some readjustment of estimates.

 

[flixden]

2% is closer to 1.5-1.6kWh, your battery is not 100kWh, and with rounding we don't exactly know... When the car is awake it consumes 200-250w constantly whereas it only consumes 20w or less asleep. Every time you wake the car up, it might stay awake for 30 minutes, an hour... No one knows the exact logic but it's not just on-off in an instant. The best is to leave it alone, and not fret small changes like this since we cannot even tell with certainty if it is real energy consumption or some readjustment of estimates.

Yeah, good point, 2% is less than 2KWh, and then there is rounding. Not sure what I was thinking .

 

[johnnycnote]

2% is not a big deal IMHO

 

[jjrandorin]

Yeah, need to watch it more, I guess.

At the risk of being misunderstood or you thinking I am attacking you (I am not), I will say that since I have been here, I have seen this situation play out 100s of times (at least 100s). By "This situation" I mean,:

"New owner, goes down the rabbit hole of "omg the battery!?!?!?!?" reads dozens of threads on battery health, maintenance etc, usually signs up for at least 1 (but many times multiple) monitoring services, and then proceeds to get stressed out by every small thing the data reports their car does and posts questioning it."

Usually, veteran owners will either say "here is how the data works" and / or " just drive it for a while, you will get a feel for how all this works" and that works for some people, and not for others.

Again, I am not attacking you, just stating that I have seen. I am in the "just drive it for a while, you will get used to how things work" camp, so thats what I suggest.

Yeah, good point, 2% is less than 2KWh, and then there is rounding. Not sure what I was thinking .

You were thinking "This car has the biggest battery I have ever owned, and I want it to last for XX years. I need to dig into exactly what this thing is doing to make sure I am not doing something wrong"

I can tell this by your previous posting in various threads, and statements like:

Parked in garage around 5:00pm last night with 39% SOC, plugged in and set for a 10:00 departure the next morning, charge limit set to 50%.

Im going to suggest again that its not necessary to "Keep an eye on" a 1-2% change in battery level, and that you should drive the car for a couple of months and spot check stuff but not worry about it... but im not sure that fits what you want.

 

[flixden]

At the risk of being misunderstood or you thinking I am attacking you (I am not), I will say that since I have been here, I have seen this situation play out 100s of times (at least 100s). By "This situation" I mean,:

"New owner, goes down the rabbit hole of "omg the battery!?!?!?!?" reads dozens of threads on battery health, maintenance etc, usually signs up for at least 1 (but many times multiple) monitoring services, and then proceeds to get stressed out by every small thing the data reports their car does and posts questioning it."

Usually, veteran owners will either say "here is how the data works" and / or " just drive it for a while, you will get a feel for how all this works" and that works for some people, and not for others.

Again, I am not attacking you, just stating that I have seen. I am in the "just drive it for a while, you will get used to how things work" camp, so thats what I suggest.



You were thinking "This car has the biggest battery I have ever owned, and I want it to last for XX years. I need to dig into exactly what this thing is doing to make sure I am not doing something wrong"

I can tell this by your previous posting in various threads, and statements like:



Im going to suggest again that its not necessary to "Keep an eye on" a 1-2% change in battery level, and that you should drive the car for a couple of months and spot check stuff but not worry about it... but im not sure that fits what you want.

I am not offended at all by your post, I see your point. Appreciate the response!
As a new owner, I am of course very inexperienced with the new Tesla. Just trying to learn as much as I can, and as an electrical engineer, I am naturally interested in finding out the details and understanding things.

 

[GtiMart]

If you DO want all the nitty gritty details you can read the fine (and long) threads in the model 3 battery subforum, they apply to your Y. You can also think of getting ScanMyTesla and look at your numbers. With that said, the most important is to follow what jjrandorin just said, don't get hung up on details.

 

[jjrandorin]

I am not offended at all by your post, I see your point. Appreciate the response!
As a new owner, I am of course very inexperienced with the new Tesla. Just trying to learn as much as I can, and as an electrical engineer, I am naturally interested in finding out the details and understanding things.

If you are an engineer in your day job, then perhaps I retract my statement about the monitoring services I said to you earlier (in another thread). I say that because its more likely you can absorb the data without stressing out too much, however its likely that because there is so much discussion around the topics of "the battery", your "engineering curiosity" may get lumped in with most other new owners "stress".

Anyway, data types (which many engineers are) tend to love all that data, so maybe re consider that advice I gave you about "dont do it".

 

[patrick40363]

Parked in garage around 5:00pm last night with 39% SOC, plugged in and set for a 10:00 departure the next morning, charge limit set to 50%. Sentry mode is off. Checked last night at 10:00pm, 38% left. Just now, at 6:30, it's down do 37%.
Seems excessive to me to lose 2% in 13 hours with Sentry off.
What could be causing this?
I searched, but could not really find an answer that applies to me.

Why are you charging to only 50% ?

 

[flixden]

Why are you charging to only 50% ?

I don't need more than 60-70 miles daily, 50% is plenty for me on a regular daily basis.
I will charge to whatever is needed when I take a longer trip, of course.
50% or below seems to be the sweet spot for battery health, so it doesn't seem to make sense to charge higher on a daily basis (for me) as it's not needed at all.