Three weeks vacation coming, should I leave my M3 plugged-in ?

[dn325ci]

I leave mine at 50%. That is basically the nominal pack voltage, which of course it loves! Set it, forget it. Me, I'm such a geek I check in on it every few days.

 

[zoomer0056]

I understand this and intentionally open the app to wake it up. Loosing some SoC is not a big deal for me.

You can use the Tessie app without without waking up the car.

 

[kimwin]

I believe the important part is to really understand what's good for the main battery when it's in storage for sometimes.
My understanding are:
1) do not let the main battery goes down to 0% as it will also stop charging the LV battery. If the LV battery is dead, you cannot even open its door, trunk, etc....
2) keep the main battery charged around 50%-60% is best for its longevity while it's in storage
3) charge it to 100% for the BMS to re calibrate for accurate assessment of battery SoC before one resumes driving the car.

With these understandings:
1) I will leave home with SoC around 50% or higher (whatever SoC is at that time).
2) Set charge limit to 50%, leave the car plugged in. Charging may NEVER happen if SoC did not go below 50% limit during vacation.
3) A day before going home, set charge limit to 100% to get full charge and BMS calibration.

 

[E90alex]

No need for 100% charge when returning unless LFP battery. Even then it’s not really needed.

 

[AAKEE]

2) keep the main battery charged around 50%-60% is best for its longevity while it's in storage

There is no support for the theory that 50-60% causes the lowest degradation from calendar aging (in storage, only calendar aging happens).

99% of all research shows that the lower the SOC, the less calendar aging.
Calendar aging is also affected by temperature so if you have a chance to choose, lower temp is better.

This is a good sum up of wht researchers often find

 

[3sr+buyer]

keep the main battery charged around 50%-60% is best for its longevity while it's in storage

Generally lower state-of-charge (but not below 0%) is better in terms of avoiding battery degradation over time. For NCA batteries, it is best to minimize time over 55%. For LFP batteries, it is best to minimize time over 70%, although it may matter less than with NCA batteries.

Since the Tesla UI does not allow setting a target charge below 50%, leaving the car plugged in with the target charge set to 50% is an easy safe thing to do for long term parking (start the long term parking below 55% for NCA battery or 70% for LFP battery).

Charging to 100% when you get back is mostly for LFP batteries in case the BMS loses the true state of charge at 50% for a long period of time.

 

[kimwin]

I left the car plugged in, at 81% SoC which is what left after a few days driving from a full charge. I set charging limit to 60%. I have been away for 5 days, the SoC is now 80%.
I think my M3 will never charge during my vacation as the SoC does not fall below 60%.

 

[Rocket_man]

I believe the important part is to really understand what's good for the main battery when it's in storage for sometimes.
My understanding are:
1) do not let the main battery goes down to 0% as it will also stop charging the LV battery. If the LV battery is dead, you cannot even open its door, trunk, etc....
2) keep the main battery charged around 50%-60% is best for its longevity while it's in storage
3) charge it to 100% for the BMS to re calibrate for accurate assessment of battery SoC before one resumes driving the car.

With these understandings:
1) I will leave home with SoC around 50% or higher (whatever SoC is at that time).
2) Set charge limit to 50%, leave the car plugged in. Charging may NEVER happen if SoC did not go below 50% limit during vacation.
3) A day before going home, set charge limit to 100% to get full charge and BMS calibration.

I also have a Model 3 RWD with the LFP battery. I've had the car a little over 1 year and its my first EV so I'm still learning. I tend to over analyze things, but I think your strategy looks good to me.

I normally charge my M3 RWD to 100% at the end of the week. I don't charge during the week unless it is in the summer and I've been using Cabin Overheat Protection which is hard on the battery and I have to charge mid-week. This time of year I get down to the 40% range by the end of the week. Lately I've been playing with 'Charge on Solar' to see if I can get to 100% on excess solar. The answer is Yes but depends on the variables. But I have no problem just charging off the grid.

I went on a 3 week trip soon after getting the car. I decided to leave the car unplugged in my garage and uber to the airport. I think the SOC was around 50-60% when I left. Charged it when I got back. I didn't leave it plugged in because I knew it wouldn't need a charge, and I didn't know what might happen if there was a nearby lightning strike (being paranoid with a new car!). Anyway, all was well when I got back and charged to 100%.

I just recently went on a 16 day trip. This time I charged to 100% and drove to the airport. I parked in a normal parking lot at 83% SOC. I got back 16 days later and it was at 81% SOC. I didn't check on the car once while gone. I did open the Tesla App to check on my Solar, but not the car. When I got back home I charged to 100%.

I think I just worried too much about it. I like the RWD/LFP battery and how it lets me charge to 100%. I drive whenever and wherever I want during the week and charge to 100% on the weekend. If I get down into the 40's I'll charge it back to 100%. My solar generates all the power the car needs over the year so I'm essentially driving for free. Now I just don't worry and enjoy driving the car.

 

[Bijli Ki Rani]

Um, I have a 2022 M3 LR. This is the first I'm hearing about needing to charge to 100% on a weekly (or other regular basis). I was told by the agent who did our sale that we should charge only to 80%. Have I been doing it wrong?

 

[AAKEE]

Um, I have a 2022 M3 LR. This is the first I'm hearing about needing to charge to 100% on a weekly (or other regular basis). I was told by the agent who did our sale that we should charge only to 80%. Have I been doing it wrong?

The Long Range (and Performance) has another battery.

-Charge to maximum* 80% for daily use.
-Charge higher if needed for longer trips.


Max 80% daily, lower than 80% is actually better but 80% will do it for you.

 

[DuncanM]

Um, I have a 2022 M3 LR. This is the first I'm hearing about needing to charge to 100% on a weekly (or other regular basis). I was told by the agent who did our sale that we should charge only to 80%. Have I been doing it wrong?

It's the M3 RWD (with LFP battery) that Tesla recommends charging to 100% at least weekly. Your car's charge screen will show the recommended daily charge level.

 

[Bijli Ki Rani]

Thanks--that's a relief!

 

[kimwin]

After 3 weeks, my car battery lost 5% (from 81% down to 76%). The car charging never occur as the limit was set to 60%
As soon as I landed at our city airport, I start its charging to 100%.
Next time I will ensure the battery is below 60% at the start of a long storage period.