So...do we charge the LFP RWD Y to 100% everyday?

[chrisli79]

Looked at several post on this site as well as the internet. Seems like no one answered this question

"Can/Should you charge the battery to 100% each day?".

A common scenario is that: I charged to 100% on Monday, but now on Thursday my battery is at 30%, do I still charge to 100% or just charge to 90% and wait until Monday again to charge to 100%?

I know the manual says to charge full once per week, but hope someone can clarify this issue a bit more

 

[DuncanM]

Looked at several post on this site as well as the internet. Seems like no one answered this question

"Can/Should you charge the battery to 100% each day?".

A common scenario is that: I charged to 100% on Monday, but now on Thursday my battery is at 30%, do I still charge to 100% or just charge to 90% and wait until Monday again to charge to 100%?

I know the manual says to charge full once per week, but hope someone can clarify this issue a bit more

I've been L1 charging to 100% several times/week. It doesn't seem to have any additional effect on battery degradation, which so far, seems to be that expected due to the age of the HV battery pack (March 2022 build and ~3.5% loss at ~50K km).

I might be tempted to charge to 100% less often if I had access to an L2 charger for daily charging.

 

[drdumont]

I've been L1 charging to 100% several times/week. It doesn't seem to have any additional effect on battery degradation, which so far, seems to be that expected due to the age of the HV battery pack (March 2022 build and ~3.5% loss at ~50K km).

I might be tempted to charge to 100% less often if I had access to an L2 charger for daily charging.

Have you tried entering a service ticket and asking the question? I've used this ploy and had almost immediate responses, even a phone call from the local Service Center.

 

[DuncanM]

Have you tried entering a service ticket and asking the question? I've used this ploy and had almost immediate responses, even a phone call from the local Service Center.

It's an inevitable process and there's no way to really slow it down, as least based upon my experience and that of others:

Degradation

teslalogger.de

in the above link above you can display data plots from thousands of cars -select the M3 LFP models to view battery degradation vs distance driven, but be aware that distance driven tends to be similar for cars with the same time from new:

For some reason the 55 and 60.5 kw battery pack cars are mixed together but you can see where the 60.5 kw cars start (437 km). This is a rough plot of mine (red line over the data plot):

 

[bruce4000]

The chemistry of the situation is that charging to 100% and letting it sit is detrimental to Nickel based and LFP but much less so for LFP. Meanwhile, the voltage vs charge curve for LFP is much less linear than for Nickel so by charging LFP to 100% once a week the bms can recalibrate. So probably ok to charge to 100% everyday for LFP if you really have to but I would charge to 80% or so everyday (depending on your commute) and then once a week to 100% like Tesla says.

 

[E90alex]

Easiest method if you don’t want to over think it: charge to 100% every time it’s plugged in (except when supercharging on a trip)

Method that can help reduce degradation: keep daily charge level below 70% if that is enough for your daily use. Then charge to 100% once a week or every 2 weeks.

 

[zknobody]

This is a good question, I'm wondering the same thing - have a L2 at home

I've been only charging to 100% once a week (summer) but as the winter rolls in I might want to keep the car plugged in daily however I'm also not sure if I should set that daily charge to 100 or lower it.

 

[chrisli79]

This is a good question, I'm wondering the same thing - have a L2 at home

I've been only charging to 100% once a week (summer) but as the winter rolls in I might want to keep the car plugged in daily however I'm also not sure if I should set that daily charge to 100 or lower it.

This is exactly my question as well, for now I'm not charging to 100 daily and going to be using SUNDAY as the day to recharge to 100%

All other days just recharge to about 90....

 

[johnny_cakes]

Easiest method if you don’t want to over think it: charge to 100% every time it’s plugged in (except when supercharging on a trip)

Method that can help reduce degradation: keep daily charge level below 70% if that is enough for your daily use. Then charge to 100% once a week or every 2 weeks.

This is good advice. This method to reduce degradation is based on scientific data that is posted in the battery forums.

 

[cesterley]

I have another scenario I have not seen in the forums (as far as I can tell).
2023 Model 3 RWD. LFP Battery.
My commute is less than 10 miles a day. I have access to free L2 charging at my work, but I cannot leave it charging for the full day.

1. Should I charge it from 85-90% to 100% each day (Monday-Friday)? And not plug it in any other time?
2. I'd rather not leave it plugged in all the time at home (Tesla recommendation from manual) and have it charge on my dime. I guess I could reduce the charge limit to 70% or so when at home so as not to use home service to charge battery, but meet the "always plugged in" recommendation.
3. Simply charge once or twice a week for free at work, and not have it plugged in any other time?
4. Stop worrying about it and just charge when convenient, and enjoy the ride?

thanks!

 

[E90alex]

I would probably do “3” and try to time it so you can charge to 100% before the weekend.

How long can you leave it plugged in at work for?

 

[cesterley]

I'm only allowed to stay on the charger until it is full. Honor system, but we all know whose cars are whose.

 

[zknobody]

#4 but we all know none of us can do that

My plan:

Summer: I charge to 100 once per week and top off to max 70 if I need the mileage mid week
Winter: Plug in on all cold days max 70, charge to 100 once per week

I see your challenge wanting to use the free L2 but it wouldn't work for me in the winter.

 

[Black306]

I have another scenario I have not seen in the forums (as far as I can tell).
2023 Model 3 RWD. LFP Battery.
My commute is less than 10 miles a day. I have access to free L2 charging at my work, but I cannot leave it charging for the full day.

1. Should I charge it from 85-90% to 100% each day (Monday-Friday)? And not plug it in any other time?
2. I'd rather not leave it plugged in all the time at home (Tesla recommendation from manual) and have it charge on my dime. I guess I could reduce the charge limit to 70% or so when at home so as not to use home service to charge battery, but meet the "always plugged in" recommendation.
3. Simply charge once or twice a week for free at work, and not have it plugged in any other time?
4. Stop worrying about it and just charge when convenient, and enjoy the ride?

thanks!

Ditto; have access to L2 charging at work. Got into the habit of driving my wife's car to work about once a week. Rarely charge her car, or mine, at home lately.

 

[cesterley]

#4 but we all know none of us can do that

My plan:

Summer: I charge to 100 once per week and top off to max 70 if I need the mileage mid week
Winter: Plug in on all cold days max 70, charge to 100 once per week

I see your challenge wanting to use the free L2 but it wouldn't work for me in the winter.

I'm in North Carolina - so I'll have to see what I need to do in our mild winters... thanks for the insights!

 

[archanfel]

I wouldn't be able to even if I tried unless I kept it plugged in all weekend. I am actually a little worried about warranty implication given Tesla knows everything about our cars. I kept mine at around 50% most of the time, charged to 100% three times so far. Lost over 2% capacity after less than 2 months already.

 

[johnny_cakes]

I wouldn't be able to even if I tried unless I kept it plugged in all weekend. I am actually a little worried about warranty implication given Tesla knows everything about our cars. I kept mine at around 50% most of the time, charged to 100% three times so far. Lost over 2% capacity after less than 2 months already.

The concern about not charging to 100% every week with LFP is that the BMS will lose track of the SoC, given LFP's flat voltage curve around the middle. The concern from a practical perspective is that you can be left stranded with a depleted battery even when the display shows SoC above 0%. If it's been a while since your last charge to 100%, I would avoid letting the battery level get too close to 0%. This "charge to 100% weekly" is not for battery health. In fact, the lower the SoC the better (especially preferrable is to stay below 70% where you can half the battery degradation, see this for the research behind it).

Charging habits have no impact on warranty. That said, unless your battery fails, it's very unlikely that your capacity will drop below the 70% warranty threshold during the warranty period.

 

[archanfel]

The concern about not charging to 100% every week with LFP is that the BMS will lose track of the SoC, given LFP's flat voltage curve around the middle. The concern from a practical perspective is that you can be left stranded with a depleted battery even when the display shows SoC above 0%. If it's been a while since your last charge to 100%, I would avoid letting the battery level get too close to 0%. This "charge to 100% weekly" is not for battery health. In fact, the lower the SoC the better (especially preferrable is to stay below 70% where you can half the battery degradation, see this for the research behind it).

Charging habits have no impact on warranty. That said, unless your battery fails, it's very unlikely that your capacity will drop below the 70% warranty threshold during the warranty period.

Interesting, so I should keep it at 20%? I guess my previous setting of 80% was probably bad for the battery, assuming the car keep the battery cooled to 25C at all time.

 

[E90alex]

Idk where you got 20% from

 

[archanfel]

Idk where you got 20% from

Based on the chart, 10% or less have the lowest calendar loss at 25C, significantly less than at 40-60%. Not sure I am comfortable going that low though.