Charging Level Question

[Yellow Buddy]

Thanks for all the replies. I have the dual max battery and so I’ll follow the NMC guidance above.

FWIW, I’ve got several Teslas using NMC. They’ll all degrade and level off at about 85%. And that’s with well over a hundred thousand miles, multiple cycles to 100%, and one uses DCFc almost exclusively. So even if you don’t follow it, that’ll hopefully give you an idea of the results of that scenario.

Sponsored

 

[Nixapatfan]

If you don't plan on keeping it outside the warranty period or leasing it then don't worry about it charge it as you wish and let that be someone else's problem.

I only charge to 80% just so regen isn't limited.

 

[RMSko]

I think the fact that the opinions are all over the place in this thread alone shows that more specific guidance is needed. It would be great for car manufacturers to give a one page handout at deliver that says what it should be charged to with various driving ranges, e.g., if you drive less than 50 miles per week do this, etc. At this point it is unrealistic to expect the consumer to figure it out.

BTW - I did read the manual and I don’t see where it covers the recommended charging range at all. It simply says:

“For Model Year 2025 and 2026 Dual Standard vehicles, charge to 100% at least once every two weeks or every 500 mi (800 km) to ensure optimal range estimation, charging speed, and regenerative braking. A notification appears if it has been too long since you fully charged the battery.”

So, if you have a dual standard car, it will at least do what the poster above wanted and tell you that you need to charge to 100%. BUT, if you have a max battery or tri or quad, I don’t see any information. They should at least give you that same information for all the configurations.

 

[savethemanual]

If you don't plan on keeping it outside the warranty period or leasing it then don't worry about it charge it as you wish and let that be someone else's problem.

I only charge to 80% just so regen isn't limited.

This brings up a good point for those in the used EV market, would be nice to get a report of the charging history. I've purchased a few used TV's over the years for a second room, I can go into the service menu and see how many hours it was on....was able to call out the seller for saying it was barely used

 

[UnsungZero_OldTimeAdMan]

I think the fact that the opinions are all over the place in this thread alone shows that more specific guidance is needed. It would be great for car manufacturers to give a one page handout at deliver that says what it should be charged to with various driving ranges, e.g., if you drive less than 50 miles per week do this, etc. At this point it is unrealistic to expect the consumer to figure it out.

BTW - I did read the manual and I don’t see where it covers the recommended charging range at all. It simply says:

“For Model Year 2025 and 2026 Dual Standard vehicles, charge to 100% at least once every two weeks or every 500 mi (800 km) to ensure optimal range estimation, charging speed, and regenerative braking. A notification appears if it has been too long since you fully charged the battery.”

So, if you have a dual standard car, it will at least do what the poster above wanted and tell you that you need to charge to 100%. BUT, if you have a max battery or tri or quad, I don’t see any information. They should at least give you that same information for all the configurations.

Official guidance for NMC is in the UI. Look at your charging screen and the presets. 70% for daily. 85% for extended. That 70% recommendation is conservative. Coming for corporate, whether it's EVs or healthcare, recommendations are expected to be conservative... because no business entity would knowingly increase their legal liability. None.

And opinions in an online forum? of course it's going to be varied. That's nature of the internet, full stop.

Stanford University and others recently published long term studies on battery deg. All have concluded that with newer/current tech, it isn't as bad as popular belief. Engineering Explained's information is sound and is indeed how the chemistry behaves.

 

[iamnid]

“For Model Year 2025 and 2026 Dual Standard vehicles, charge to 100% at least once every two weeks or every 500 mi (800 km) to ensure optimal range estimation, charging speed, and regenerative braking. A notification appears if it has been too long since you fully charged the battery.”

So, if you have a dual standard car, it will at least do what the poster above wanted and tell you that you need to charge to 100%.

Not only will it tell you that on the standard pack, it will actually change the max charging amount to 100% on its own if you haven't charged to 100% in about 2 weeks.

I agree with earlier posters though, you're over-thinking it. 70% seems overly cautious. 80-85% and don't worry about it -- 100% if you're starting a road trip. Unless you're charging it to 100% every day and leaving it there for hours and hours, it's unlikely you'll notice any difference between daily charging to 85% vs. 70% other than the range available to you.

 

[RMSko]

Not only will it tell you that on the standard pack, it will actually change the max charging amount to 100% on its own if you haven't charged to 100% in about 2 weeks.

I have the max battery though and so this won’t apply to me, right?

 

[UnsungZero_OldTimeAdMan]

I have the max battery though and so this won’t apply to me, right?

Does not apply. NMC does not need full charge for calibration. Because voltage curve is not as flat as LFP (which is why LFP needs it, see video linked on LFP).

 

[SwampNut]

Does not apply. NMC does not need full charge for calibration. Because voltage curve is not as flat as LFP (which is why LFP needs it, see video linked on LFP).

It absolutely does, at least on Teslas. Or more specifically to fully balance the cells and possibly recalibrate. I’ve seen this on multiple teslas that were never fully charged. They will regain a lot of range if you let them sit at 100% on the charger for a few hours.

 

[zakool21]

If you have a Standard pack you have LFP chemistry cells. These need to be charged to 100% periodically to aid software’s calibration of the way it measures state of charge (a derivative of voltage readings).



If you have Large or Max, you have NMC. Charge to 100% only if you must for long distance travel, in order to reach first available charging stop. Do not charge to 100% and let it sit at that state without use. For long trips, it’s actually better to not charge to full if charging infrastructure allows you to recharge sooner. Charging slows when approaching full. So for sake of time/efficiency, best to keep SOC to within 20-80% range. And with NMC you do not need to charge to full to calibrate software.



Regardless of LFP or NMC, if long term storage or infrequent use, around 50% is ideal. Just enough for local errands and no stress on battery chemistry. That said current state of battery tech is much less prone to degradation. Most fears are carried over from outdated past.

This is the most thorough and scientifically accurate answer.

All batteries = 50% ideal

LFP = Needs occasional 100% charge to calibrate BMS

That about sums it up.

 

[Greg Chick]

I worry more about the temperature issues than the %. Also, I think it is better that I most always charge at home at night and rarely do DCFC.

 

[azbill]

It absolutely does, at least on Teslas. Or more specifically to fully balance the cells and possibly recalibrate. I’ve seen this on multiple teslas that were never fully charged. They will regain a lot of range if you let them sit at 100% on the charger for a few hours.

NMC do need recalibration occasionally. The best way to do it is to deplete the battery to 10% or less, then let it sit 3 hours. Then charge it to 100% and let it sit 3 hours. Do this a couple of times a year. You can also get an idea of battery health when doing this by seeing how many kwh went into that charge.

 

[UnsungZero_OldTimeAdMan]

NMC do need recalibration occasionally. The best way to do it is to deplete the battery to 10% or less, then let it sit 3 hours. Then charge it to 100% and let it sit 3 hours. Do this a couple of times a year. You can also get an idea of battery health when doing this by seeing how many kwh went into that charge.

I would not recommend doing this via DCFC. But to each his own.

 

[SwampNut]

NMC do need recalibration occasionally. The best way to do it is to deplete the battery to 10% or less, then let it sit 3 hours. Then charge it to 100% and let it sit 3 hours. Do this a couple of times a year. You can also get an idea of battery health when doing this by seeing how many kwh went into that charge.

Yeah, I can't remember where I got the info, I think in the service menu on the Tesla, but I ran it to 3% then gave it a LONG time to hold (balance) at 100%. I too read that twice a year is good. I do road trips many times per year so it ends up seeing 100% at least every quarter.

I would not recommend doing this via DCFC. But to each his own.

How the hell would you even do this at a DCFC charger? And...why? And it would stop, pretty sure, so it would never work. You need an EVSE that will continue pumping power past 100% as it does the long-running balancing.

 

[azbill]

I would not recommend doing this via DCFC. But to each his own.

It needs to be done on L2, NOT DCFC. There will be no cell balancing when using DCFC. And you need to let the battery voltage reach a resting state for the BMS to figure out the real state of charge, that is why you wait 3 hours before and after charging.

Sponsored