How should I charge the battery if I don’t drive everyday?

[Koolio46]

I’ll be purchasing one in the next couple of months and an wondering what the recommendation is if I don’t drive the car everyday. In fact, I drove about 7,000 miles per year and I’ll go for 5 days without driving the car.

What’s the best way to charge the battery but keep the longevity if the battery?

I’m assuming it’s not to keep it plugged in and charged to 80% the entire time. Perhaps, don’t plug the car in everyday and use it until I get down to 20-30% battery and then charge it up to 80%?

 

[Zoomit]

You'll get a lot of responses from us experts, but here's my list of guidance and quotes from Tesla and Elon Musk:

How to take care of your battery without stressing: advice for new owners.

This guidance is likely written to be as simple as reasonable and also ensure the battery meets it's warranty period. It is not likely what would maximize battery life, especially in your particular situation, usage pattern, or climate.

The comments below are the attempt by the community to customize this guidance, and other "knowledge", to meet your particular situation.

 

[captanzuelo]

For a seldom driven Tesla, I'd be worried about the 12V battery health as well.

 

[Koolio46]

You'll get a lot of responses from us experts, but here's my list of guidance and quotes from Tesla and Elon Musk:

How to take care of your battery without stressing: advice for new owners.

This guidance is likely written to be as simple as reasonable and also ensure the battery meets it's warranty period. It is not likely what would maximize battery life, especially in your particular situation, usage pattern, or climate.

The comments below are the attempt by the community to customize this guidance, and other "knowledge", to meet your particular situation.

Great info, thanks!

Looks like best thing is to keep it plugged in when not driving for a few days and at 80-90% SoC.

 

[jf64k]

From the MY Owner’s Manual

“About the Battery

Model Y has one of the most sophisticated battery systems in the world. The most important way to preserve the Battery is to LEAVE YOUR VEHICLE PLUGGED IN when you are not using it. This is particularly important if you are not planning to drive Model Y for several weeks. When plugged in, Model Y wakes up when needed to automatically maintain a charge level that maximizes the lifetime of the Battery.

There is no advantage to waiting until the Battery’s level is low before charging. In fact, the Battery performs best when charged regularly.”

 

[TomServo]

For a seldom driven Tesla, I'd be worried about the 12V battery health as well.

why, doesn’t the main pack keep the 12V battery topped off even when parked for days.

 

[TMThree]

Lengthy duration at high soc should be avoided.

Deep discharges should be avoided.

High temps at >50% SoC should be avoided.

You can't avoid most of the above while using the car, but you certainly can when it's parked and idle. Set it to 50% and keep it plugged in, or set it to 50% and don't plug it in (while making sure sentry and other stuff is disabled).

If you don't need to drive the car far, keep the car charged near 50%. For example, if you consume 20% of your battery a day, consider charging to 60% and ending at 40%, rather than doing 90% to 70%. Obviously add some spare range if this is your only vehicle and you need to drive somewhere in a hurry.

Looks like best thing is to keep it plugged in when not driving for a few days and at 80-90% SoC.

That would be less than ideal. See charts below for why keeping it at high SoC for days on end is not great. Battery damage is cumulative over time. It's a war, not a battle.

 

[Koolio46]

Lengthy duration at high soc should be avoided.

Deep discharges should be avoided.

High temps at >50% SoC should be avoided.

You can't avoid most of the above while using the car, but you certainly can when it's parked and idle. Set it to 50% and keep it plugged in, or set it to 50% and don't plug it in (while making sure sentry and other stuff is disabled).

If you don't need to drive the car far, keep the car charged near 50%. For example, if you consume 20% of your battery a day, consider charging to 60% and ending at 40%, rather than doing 90% to 70%. Obviously add some spare range if this is your only vehicle and you need to drive somewhere in a hurry.




That would be less than ideal. See charts below for why keeping it at high SoC for days on end is not great. Battery damage is cumulative over time. It's a war, not a battle.

View attachment 584116 View attachment 584117

Thanks very much for this. Super helpful.

Keeping it at 50% would be more than enough capacity for 95% of my weekly driving most of my drives are short distances 20-50 miles. Then, when we go for a longer trip, I can charge it to 80%.

I see you have motorcycles...nice. Same here. I’ll be using the Y to tow my bike to the track (I have a very light trailer).

 

[captanzuelo]

why, doesn’t the main pack keep the 12V battery topped off even when parked for days.

I believe the main battery only starts charging the 12V when it is 50% drained.

 

[ftmaybe]

For example, if you consume 20% of your battery a day, consider charging to 60% and ending at 40%, rather than doing 90% to 70%. Obviously add some spare range if this is your only vehicle and you need to drive somewhere in a hurry.

I did this religiously with my wife's model 3 for the first 8000 miles or so, and still the range dropped almost 10% from new.

Then you got elon saying charge to 90%, and several people here on the forum reporting that's what they do and their range has not dropped.

Sure would be less of a hot topic if people were getting consistent results..

 

[MY-Y]

The performance versions, they aren't as fast at 50% SoC compared to higher charges. I'm not sure how the AWD performance changes with SoC. I suspect it keeps full power at a much lower SoC since it draws less current. (Anybody have this info?)

 

[frankvb]

I did this religiously with my wife's model 3 for the first 8000 miles or so, and still the range dropped almost 10% from new.

I think there are two different things going on here. Keeping the charge level as close to 50% is good by itself.

However, it will make the battery management system capacity tracking drift off, which causes it to adjust the maximum capacity even when it has not changed. Doing a few e.g. 30-90% cycles every now and then should fix that. There is another thread explaining that.

How I Recovered Half of my Battery's Lost Capacity

 

[TMThree]

I did this religiously with my wife's model 3 for the first 8000 miles or so, and still the range dropped almost 10% from new.

Then you got elon saying charge to 90%, and several people here on the forum reporting that's what they do and their range has not dropped.

Sure would be less of a hot topic if people were getting consistent results..

You still need to charge to 90% once or twice a month just to keep the BMS from getting its values skewed. You would have less capacity loss than someone who daily charges to 90% even if the estimate is off.

My car is still within 3 miles of 325 mile range after 17,000 miles.

PS: Range estimation is very slow. When Tesla rolled back the 325 mile estimate to 310 miles, and then gave us back the 325 mile range on the LR RWD, it took about 5 months for my estimated range to go back 15 miles to 325 that I had originally.

 

[tccartier]

why, doesn’t the main pack keep the 12V battery topped off even when parked for days.

It will if the 12-volt battery charge level or detected voltage drops to a certain point it will close the contactors on the traction pack and energize the dc inverter to maintain the 12 volt battery. Best thing just set your charge somewhere between 80 and 90% leave the vehicle plugged in and it will be fine it takes care of itself you don't need to do anything.

 

[Sebat4]

I don't have an option of charging at home so I charge the car at superchargers and sometimes at my parents. To be honest with you after reading so many posts and do's and don'ts it makes me feel like I'm not supposed to own the car because I don't have a place to charge and the battery will lose charge and charging capabilities. I just think do what you feel and enjoy the car, no matter what you will do there will be someone who will say that's not the way to do it or it's the way to do it. I personally enjoy the car and it's parked 4-5 days a week, yet it's amazing to drive and I have a lot of fun doing it, even if I charge it at the supercharger 90% of the time.

 

[Wennfred]

You can also learn what eats (drains) your battery overnight and turn those off, my model 3 stays at 93 - 94% charged for a few days or until I take it out for a spin, this keeps the charger from going on and off all the time. I also use TezLab to put the car to sleep immediately to prevent even more drain from wherever.

Need to also add, the 93% is a test I am currently doing right now while under deep sleep, I am slowly regaining some range, was down 13 mile now only 7 miles.

My pack is 240 mile range (SR+) and now I am seeing 233 Miles, haven’t driven it much either, every 12 hours I wake up, roll windows to Vent and check Stats, then I put her back to sleep, won’t charge again until I see 50%


Fred

 

[Sebat4]

You can also learn what eats (drains) your battery overnight and turn those off, my model 3 stays at 93 - 94% charged for a few days or until I take it out for a spin, this keeps the charger from going on and off all the time. I also use TezLab to put the car to sleep immediately to prevent even more drain from wherever.

Need to also add, the 93% is a test I am currently doing right now while under deep sleep, I am slowly regaining some range, was down 13 mile now only 7 miles.

My pack is 240 mile range (SR+) and now I am seeing 233 Miles, haven’t driven it much either, every 12 hours I wake up, roll windows to Vent and check Stats, then I put her back to sleep, won’t charge again until I see 50%


Fred

Thanks for the app. I like how much more info it gives me than any app so far that I have used for that.

 

[ftmaybe]

However, it will make the battery management system capacity tracking drift off, which causes it to adjust the maximum capacity even when it has not changed. Doing a few e.g. 30-90% cycles every now and then should fix that. There is another thread explaining that.

You still need to charge to 90% once or twice a month just to keep the BMS from getting its values skewed. You would have less capacity loss than someone who daily charges to 90% even if the estimate is off.

Yep. After we started losing range I started doing the 90% charges, and the deep charge of slowly going down to below 40% and then charging back up to 90%. none of it made an appreciable difference. The day we picked it up was the only day it showed 250 miles .. it was down to 226 or so before it was wrecked.

I'm not too worried about it. But I can see where it can be troubling for people, especially when they aren't getting even the "diminished" range that is on the "estimate" because they drive on the highway or something. A lot of people won't be prepared for the way EVs work.


My wife's model 3 was totaled in a hit and run a few weeks ago. So we're getting a new one, and I'm getting a Model Y. I figure I'll run two different charging regimes as we will have two new teslas and see what happens.

 

[tekdemon]

While 50% would be optimal it's not particularly harmful to have batteries sit around at 60-70% and it'd be a lot more convenient to have a little extra charge if you actually wanna go for a drive. If you have a performance model also remember that the horsepower will drop a lot once it's under about 70%.

I'd probably just set it to 65% or 70% and keep it on the charger. Really wouldn't be a big deal. If you're really super paranoid I guess you can do 60%. Just remember to occasionally do a larger charge and larger drawdown or the BMS will lose accuracy.

 

[MY-Y]

... If you have a performance model also remember that the horsepower will drop a lot once it's under about 70%.
...

How does the SoC power drop for the AWD compare? Full power to 60%, 40%?