Tesla sets charge limit to 90%

[ewoodrick]

This might be a routine. I put 50k/miles a year on a car. I'm debating leaving the MYP in PA and continuing to commute with the Prius Prime and just use the Tesla on the weekends for now. I would keep this MYP to 16k/yr and get another Prius if needed to keep up the crazy driving. We still have our 2007 Prius with over 500k+ miles. The 2017 Prime has almost 270k.

Why not drive the Model Y all the time? Add some EAP or FSD and it will completely change your 500k miles experience.
I'm assuming that you may have a little range anxiety, If you take the car on long trips, getting over range anxiety is pretty easy.

 

[ewoodrick]

Clue: the Bolt is cheap, charges slowly, but it's selling quickly.

LFP is going to be the base for everything battery. To be honest, I think the only reason it isn't already to us is that key patents didn't expire until 2022.

I'm trying to figure out if you are being facetious or serious.
Bolt sales...

Germany just celebrated turning out 4,000 Model Ys per WEEK. Let alone what Texas, Freemont, and China are making.

LFP tends to be heavier and doesn't have the best numbers. Hence why Tesla only uses them in short-range vehicles.

 

[Porkalletta]

I set it to charge to 90% at non-peak hours nightly. About a 40 mile round trip commute for me.

I have been doing the same home charge for my MXP since June 2022. No degradation at all so far.

 

[Physicslawyer]

Why not drive the Model Y all the time? Add some EAP or FSD and it will completely change your 500k miles experience.
I'm assuming that you may have a little range anxiety, If you take the car on long trips, getting over range anxiety is pretty easy.

I would put 50k/yr on it. I don't want to need a new battery in two or three years for 20k. It's too expensive for that kind of use case. I had one at 4k miles/month that I could exchange every two months for a new one. That opportunity ended though, so I bought this one. The Prius will get the bulk of the commuting miles since it's known for reliability and we don't have many high model M3 or MY as a reference.

 

[ewoodrick]

I would put 50k/yr on it. I don't want to need a new battery in two or three years for 20k. It's too expensive for that kind of use case. I had one at 4k miles/month that I could exchange every two months for a new one. That opportunity ended though, so I bought this one. The Prius will get the bulk of the commuting miles since it's known for reliability and we don't have many high model M3 or MY as a reference.

Still stand by my statement. AFAIK, there is absolutely nothing suggesting that you'll need a new battery at 100k or 150k. More like 300k. And batteries haven't been that expensive.

 

[Iron]

My thinking has evolved. LOL. You learn things as you experiment.

Charge limit is now set to 70% and I think this is where it will stay for a while. That gives me roughly 230 mi to start out each day. Again, daily commute is 40 mi RT and I plug into a wall connector nightly.

I do have a few noob questions....

1. I have departure set for 6:30 AM. Is there any reason to use precondition during balmy weather? I have it off. Temps have been in the high fifties to sixties here at night and 70-80 F during the day. Of course, they'll only get warmer this time of year. I understand using it during the winter to get the battery up to temp. (Note: I don't care about setting cabin temps. The car is garaged.)

2. I am not using off-peak charge feature yet (util peak charges run June thru Sept, 3-8 PM weekdays) but I've seen it mentioned that off peak should be set to end at the same time as scheduled departure (in my case, 6:30 AM). Can someone please explain why that's beneficial?

3. I've set sentry mode to exclude home and work, but it still enables at either location. Why is this? I've seen mention of adding it to favorites then excluding favorites, but what If I visit a favorite place often and want it turned on automatically?

 

[ewoodrick]

My thinking has evolved. LOL. You learn things as you experiment.

Charge limit is now set to 70% and I think this is where it will stay for a while. That gives me roughly 230 mi to start out each day. Again, daily commute is 40 mi RT and I plug into a wall connector nightly.

I do have a few noob questions....

1. I have departure set for 6:30 AM. Is there any reason to use precondition during balmy weather? I have it off. Temps have been in the high fifties to sixties here at night and 70-80 F during the day. Of course, they'll only get warmer this time of year. I understand using it during the winter to get the battery up to temp. (Note: I don't care about setting cabin temps. The car is garaged.)

2. I am not using off-peak charge feature yet (util peak charges run June thru Sept, 3-8 PM weekdays) but I've seen it mentioned that off peak should be set to end at the same time as scheduled departure (in my case, 6:30 AM). Can someone please explain why that's beneficial?

3. I've set sentry mode to exclude home and work, but it still enables at either location. Why is this? I've seen mention of adding it to favorites then excluding favorites, but what If I visit a favorite place often and want it turned on automatically?

1) I think that it shows that you are from Atlanta. If so, no need to set any preconditioning. If it's cold outside, just turn the heat on a minute or so before you leave. (and if you increase your charge to the more recommended 80-90% it becomes less of an issues) I'm north of Atlanta and I've NEVER preconditioned my car.

2) Are you on a time of day rate? That's not quite as common in the Atlanta area (sometimes your monthly bills may be more). But if on a TOD rate, how many miles do you use daily? How long does it take you to charge. If you are on a L2 charger and like most people, the only thing that you really care about is that you don't start charging too early. There are people in much colder climates who have to precondition their batteries because it is always well below freezing in the morning (not the case in Atlanta). They want to make sure that the car is topped off and battery warmed up.

3) Don't know, never use it.

 

[Iron]

1) I think that it shows that you are from Atlanta. If so, no need to set any preconditioning. If it's cold outside, just turn the heat on a minute or so before you leave. (and if you increase your charge to the more recommended 80-90% it becomes less of an issues) I'm north of Atlanta and I've NEVER preconditioned my car.

2) Are you on a time of day rate? That's not quite as common in the Atlanta area (sometimes your monthly bills may be more). But if on a TOD rate, how many miles do you use daily? How long does it take you to charge. If you are on a L2 charger and like most people, the only thing that you really care about is that you don't start charging too early. There are people in much colder climates who have to precondition their batteries because it is always well below freezing in the morning (not the case in Atlanta). They want to make sure that the car is topped off and battery warmed up.

3) Don't know, never use it.

Yes, I'm just outside of ATL and work in the city. Buford is just up the road.


Indeed, I'm on a "time of use" rate and until June, everything is considered off-peak. My commute is 40 miles round trip, so roughly 45 miles a day used if i'm doing a bit of running around in the neighborhood. Yes, level 2 wall connector. It only takes a few hours to charge if that, and the scheduled departure of 6:30 means it starts charging sometime after 3:30 or so.

 

[arbitrage000]

My thinking has evolved. LOL. You learn things as you experiment.

Charge limit is now set to 70% and I think this is where it will stay for a while. That gives me roughly 230 mi to start out each day. Again, daily commute is 40 mi RT and I plug into a wall connector nightly.

I do have a few noob questions....

1. I have departure set for 6:30 AM. Is there any reason to use precondition during balmy weather? I have it off. Temps have been in the high fifties to sixties here at night and 70-80 F during the day. Of course, they'll only get warmer this time of year. I understand using it during the winter to get the battery up to temp. (Note: I don't care about setting cabin temps. The car is garaged.)

2. I am not using off-peak charge feature yet (util peak charges run June thru Sept, 3-8 PM weekdays) but I've seen it mentioned that off peak should be set to end at the same time as scheduled departure (in my case, 6:30 AM). Can someone please explain why that's beneficial?

3. I've set sentry mode to exclude home and work, but it still enables at either location. Why is this? I've seen mention of adding it to favorites then excluding favorites, but what If I visit a favorite place often and want it turned on automatically?

I can help with #2. The reason to do this even when you don't have off peak rates is that then when you get home in the evening and plug in the car doesn't charge immediately. Instead it will charge "just in time" to leave at you Scheduled Departure Time. The benefits of this is not sitting at a high state of charge overnight (although if just charging to 70% that probably isn't a big deal) AND that by charging just before departure it warms the pack for better regen. Doing the off peak time is more important for people who charge up to 90% as then you really don't want the car sitting every night at 90% and it is also more important in colder temps to have a warm battery. If it's middle of summer and you are only charging to 70% then it won't matter and you can switch off-peak off and just let the car charge when you get home. Then it will warm the cabin at your scheduled departure time but will have finished charging the previous evening or overnight (depending on SOC when you got home in the evening).

 

[Iron]

I can help with #2. The reason to do this even when you don't have off peak rates is that then when you get home in the evening and plug in the car doesn't charge immediately. Instead it will charge "just in time" to leave at you Scheduled Departure Time. The benefits of this is not sitting at a high state of charge overnight (although if just charging to 70% that probably isn't a big deal) AND that by charging just before departure it warms the pack for better regen. Doing the off peak time is more important for people who charge up to 90% as then you really don't want the car sitting every night at 90% and it is also more important in colder temps to have a warm battery. If it's middle of summer and you are only charging to 70% then it won't matter and you can switch off-peak off and just let the car charge when you get home. Then it will warm the cabin at your scheduled departure time but will have finished charging the previous evening or overnight (depending on SOC when you got home in the evening).

Thanks for the response. I'm already using scheduled departure alone and it's doing the same thing. As I said in my previous post, it doesn't start charging till around 3:30 AM and completes by 6:30. Off peak is charging is not enabled as yet.

 

[arbitrage000]

Thanks for the response. I'm already using scheduled departure alone and it's doing the same thing. As I said in a previous post, it doesn't start charging till around 3:30 AM and completes by 6:30. Off peak is charging is not enabled as yet.

Ah...interesting. When I tried to do it that way it would always just start charging as soon as I plugged in. Maybe I should try again and see if I can figure out why mine is doing it like that.

 

[Iron]

Ah...interesting. When I tried to do it that way it would always just start charging as soon as I plugged in. Maybe I should try again and see if I can figure out why mine is doing it like that.

Maybe something was fixed with updates. Try it again and disable off peak.

 

[jcanoe]

The earliest implementation of scheduled departure charging for the Tesla Model Y assumed that the off-peak period or window when the local electrical utility power grid was least being used always ended at 0630, your local time.

 

[Iron]

Okay. So this specific text below from the manual, is what I find confusing. Even though I do (or will staring in June) have peak/off peak rates, scheduled departure alone completes charging just before I'm ready to leave. So why would I even need to do this?

"Note
Choosing Off-Peak Charging can reduce energy costs even in market regions where off-peak utility rates are not applicable. For example, if charging starts as soon as you plug in, charging may complete much sooner. This causes the Battery to cool down to ambient temperatures and requires energy to warm it back up by your departure time. Therefore, even if off-peak utility rates are not applicable to you, it is recommended that you set Off-Peak Hours to the same time as your departure time in order to reduce energy consumption."

 

[jcanoe]

Okay. So this specific text below from the manual, is what I find confusing. Even though I do (or will staring in June) have peak/off peak rates, scheduled departure alone completes charging just before I'm ready to leave. So why would I even need to do this?

"Note
Choosing Off-Peak Charging can reduce energy costs even in market regions where off-peak utility rates are not applicable. For example, if charging starts as soon as you plug in, charging may complete much sooner. This causes the Battery to cool down to ambient temperatures and requires energy to warm it back up by your departure time. Therefore, even if off-peak utility rates are not applicable to you, it is recommended that you set Off-Peak Hours to the same time as your departure time in order to reduce energy consumption."

Not all Off-Peak rate periods start and end at the same time. 0630 is common time for the end of an off-peak window but some off-peak windows end at 0600 or 0700. In some areas there are multiple off-peak rate windows over 24 hours. That scenario is challenging as the Tesla Model Y does not support Scheduled Charging and Scheduled Departure Charging at the same time (you can choose one or the other.) Some third party apps for the Tesla Model Y can support multiple charging windows and different schedules for the days of the week.

Your Tesla charging options (without using a 3rd party app):

1) Plug in and start charging: Plug in and start charging immediately as soon as you plug in. Charging will continue until the set charging limit has been reached.

2) Scheduled Charging: Plug in and start charging at a specific time each day, i.e. 10PM. Charging will continue until the set charging limit has been reached.

3) Scheduled Departure Charging: With no Off-Peak rate window set this used to default to always completing by 0630 (your local time.)

Related - Scheduled Departure Preconditioning: Automatically preconditions the Tesla Model Y passenger cabin and battery (in cold weather) for passenger comfort, optimal battery performance, maintain regenerative braking that would otherwise be unavailable due to the battery being too cold. Can be set to precondition on weekdays or every day.

4) Off-Peak Charging: You enter the end time of the Off-peak window, i.e. 0600 and the Tesla Model Y will attempt to always complete charging by this time. This works best with Level 2 (240) charging as with Level 1 (120V) charging there may not be enough time available to charge to the set charging limit before the end of the Off-peak window.

 

[arbitrage000]

Okay. So this specific text below from the manual, is what I find confusing. Even though I do (or will staring in June) have peak/off peak rates, scheduled departure alone completes charging just before I'm ready to leave. So why would I even need to do this?

"Note
Choosing Off-Peak Charging can reduce energy costs even in market regions where off-peak utility rates are not applicable. For example, if charging starts as soon as you plug in, charging may complete much sooner. This causes the Battery to cool down to ambient temperatures and requires energy to warm it back up by your departure time. Therefore, even if off-peak utility rates are not applicable to you, it is recommended that you set Off-Peak Hours to the same time as your departure time in order to reduce energy consumption."

Yeah, this is why I started using Off-Peak because my car would always charge immediately and only by turning on Off-Peak and setting it for the same time as my Scheduled Departure did the car delay charging till closer to the Scheduled Departure (it still usually finishes 30min before).

So it is interesting that you guys are getting it to delay charging without selecting Off-Peak along with the Scheduled Departure.
I will test mine this evening to see what it does if I turn off Off-Peak.

 

[jcanoe]

Before Tesla added the ability to set the end of the Off-peak rate window the Scheduled Departure Charging always assumed 0630 (local time) was the time that charging needed to be completed. It appears that 0630 is still the default time if you don't set an end of Off-peak rate window.

In my experience charging may complete 15 to 30 minutes earlier than expected. The reason may be that time needed to warm the battery prior to charging is dependent on the temperature of the battery. To ensure charging can always be completed by the expected time the algorithm may add a large buffer of time for battery warming; also cell balancing. There is no down side if charging completes a little earlier than expected.

 

[TesslaBull]

Okay guys. I've set my charge limit to 80%. Since I have a wall connector in the garage and can charge at will, it won't be a problem and might extend the battery a little bit down the line.

This charge limit will not extend the battery. If that's your goal, here is the simple answer.

1) Set your charge limit to 55%. This will minimize battery degradation over time based on the best science and research available. This is still enough charge to cover four of your daily commutes so way more than you need daily.(In case you were to ever forget to plug in or something).

2) Plug in every day when you come home and use scheduled departure. This will keep your car at a slightly lower state of charge until you are ready to drive, which helps minimize degradation slightly more. This also warms the battery a little bit right before driving "for free" i.e. you aren't using extra electricity to precondition.

If keeping your battery in the best condition possible with the least range loss over time without any effort i.e. set it and forget it, matters to you, this is how. If that doesn't matter, just do what you want. Many, as seen in this thread, do just that. I.e. "I just set mine to 90% and charge every night." (for basically no important reason), and they are happy with degrading their battery more than necessary.

For me personally, I find a set it and forget it solution that always gives me far more range than I need while optimally minimizing battery degradation is the right solution. No downside, lots of upside. I paid extra to get the most range possible from an EV.....I'm not going to degrade it on purpose for no reason.

In the unlikely event that you ever need to do an unexpected long road trip and don't have time to top off at home, just stop at a nearby supercharger for ten minutes. Or drive a couple hours then stop. No reason to keep the car at 90% daily, IMO. I never filled up my car every single day when I drove a gas car. With Tesla, this is no different.

Another thing that you are doing to optimize your battery that is not optimal...charging to 75% and dropping to 30% before charging. Small, frequent charges are better than large infrequent. So again, points 1 and 2 above is the simple and science based method to optimally minimize battery degradation.

See post 18:

Minimising battery degradation

I have a 2021 Shanghai-built M3P with the 82 kWh Panasonic battery. My understanding is that the following four charging regimes all take the same amount of power: Daily charge - 60% to 80% Daily charge - 40% to 60% Every other day charge - 40% to 80% Every other day charge - 20% to 60%...

teslamotorsclub.com

 

[arbitrage000]

Okay. So this specific text below from the manual, is what I find confusing. Even though I do (or will staring in June) have peak/off peak rates, scheduled departure alone completes charging just before I'm ready to leave. So why would I even need to do this?

"Note
Choosing Off-Peak Charging can reduce energy costs even in market regions where off-peak utility rates are not applicable. For example, if charging starts as soon as you plug in, charging may complete much sooner. This causes the Battery to cool down to ambient temperatures and requires energy to warm it back up by your departure time. Therefore, even if off-peak utility rates are not applicable to you, it is recommended that you set Off-Peak Hours to the same time as your departure time in order to reduce energy consumption."

I did my test this afternoon. Arrived home at 30%SOC and set my charge limit to 50%. I turned off the Off-Peak setting and just left it for Scheduled Departure of 7:45AM.
As soon as I plugged in to the Tesla WC it started charging right away and screen showed time to finish charging.

So I went back to my usual setting of Off-Peak at 7:45AM also and then when I plug in the WC goes green for 1s and then back to blue and waits to charge till the next morning to reach 50% about 30mins before 7:45AM.

So I'm not sure why I'm getting different results. My results line up with how Tesla describes things in the manual that you quoted...ie if you don't use Off-Peak it doesn't delay charging. But not sure why your car will delay charging with Off-Peak deselected???

 

[Iron]

I did my test this afternoon. Arrived home at 30%SOC and set my charge limit to 50%. I turned off the Off-Peak setting and just left it for Scheduled Departure of 7:45AM.
As soon as I plugged in to the Tesla WC it started charging right away and screen showed time to finish charging.

So I went back to my usual setting of Off-Peak at 7:45AM also and then when I plug in the WC goes green for 1s and then back to blue and waits to charge till the next morning to reach 50% about 30mins before 7:45AM.

So I'm not sure why I'm getting different results. My results line up with how Tesla describes things in the manual that you quoted...ie if you don't use Off-Peak it doesn't delay charging. But not sure why your car will delay charging with Off-Peak deselected???

I'm not sure why it works this way for me and not for you, but I suggest you try it again on a weekday vs weekend. I've been playing around with all the settings and I had set up everything, including utility rates, off peak settings, etc. Off peak was all set for 3 PM weekdays then I turned it off. Went with only scheduled departure at 6:30 AM and it didn't start charging till the wee hours of the morning all week. However, when I plugged it in yesterday (Friday) evening, it began charging immediately and I could only assume because the next time 6:30 AM was rolling around, it would be Sat morning and not a weekday. So somehow it seems taking the days of the week into consideration even though that's an off peak setting. Question, @ what amperage are you charging? I've got the latest Level 2 Wall Charger set at 48A and was only recharging 15 to 20% back to set limit. Just trying to hash out any differences we might have.

PS: I didn't see anything in the manual saying "If you don't use Off-Peak it doesn't delay charging."