Charging strategy for battery longevity

[TexasEV]

I'll go with the owner's manual over a random delivery 'specialist' who may or may not have completed high school just yet. They're doing the best they can but some humans want to give an answer even when they should just say "I'm not sure. Let me get back to you."
The manual says 70%. Read it just today while waiting for my wife to come out of a store. So have taken my LEAF habit of 80% which I had extended to my Model 3, down to 70%. If the manual changes at some point, I will also.

No it doesn’t. I don’t know what you were reading, but the Model 3 owners manual does not say that.

I do agree the Tesla employees need to learn how to say “I don’t know” though.

 

[gavine]

Picked up my Model 3 last Friday in Dedham, Mass.
When I specifically asked the Delivery Specialist about charging he said that Tesla definitely recommends charging to 90%.
He made a point that the improved battery chemistry and battery management in the Model 3 was driving this recommendation.
Wondering what other people have been told?

I stopped at the new Cherry Hill, NJ location today to see the Model 3 on display. The charge on the car in the showroom was 97% (300 miles). Apparently they think over 90% is good for the battery at this location, SMH.

 

[drawfour]

I stopped at the new Cherry Hill, NJ location today to see the Model 3 on display. The charge on the car in the showroom was 97% (300 miles). Apparently they think over 90% is good for the battery at this location, SMH.

Possible that the "demo mode" doesn't lock the charging menu, and someone was playing around with the sliders and set it to a higher amount?

 

[gavine]

Possible that the "demo mode" doesn't lock the charging menu, and someone was playing around with the sliders and set it to a higher amount?

The slider was set to 90% and it was not plugged-in. It seems they "forced" it to charge to 100% for some reason and then slid it back to 90%.

 

[Redwood]

Picked up my Model 3 last Friday in Dedham, Mass.
When I specifically asked the Delivery Specialist about charging he said that Tesla definitely recommends charging to 90%.
He made a point that the improved battery chemistry and battery management in the Model 3 was driving this recommendation.
Wondering what other people have been told?

My delivery specialist at the Fremont, CA location also recommended a 90% charge.

 

[gavine]

My delivery specialist at the Fremont, CA location also recommended a 90% charge.

My vote is that they say this for user convenience and not for battery longevity.

 

[Big Dog]

My delivery specialist at the Fremont, CA location also recommended a 90% charge.

My guy in Costa Mesa said 85-90%, unless going on a trip.

But that begs the question, how does one see the percentages? I can slide the bar back and forth, but it doesn't have any label on where it stops (miles or %).

 

[goto10]

The last line is 90% and each line to the left is 10% less. The only way I've found to check the exact percentage is to change the display settings to show percentage instead of miles and then I check that number at the end of the charge.

You can also use third-party API/logging tools like TeslaFi to get/set the exact percentage.

 

[Big Dog]

^^thanks. I was just playing with that after I figured out how to access the "Gear". Strange that it doesn't show both at the same time: 90% / 280 miles (or equivalent KM).

 

[MaryAnning3]

i just picked up mine this week and he said the same thing to me. keep it 90% and plugged in all the time. I've been only using ~20% on my daily commute so wondering if i should throttle it down to 60% like others have said. hmm decisions decisions.

If you use 20% daily, my recommendation would be 45-65% or 50-70%.

 

[TexasEV]

If you use 20% daily, my recommendation would be 45-65% or 50-70%.

And watch your estimate of range get out of whack. Why are some people insistent on ignoring the experience of six years of Model S use? Many if not most of the early owners have been routinely charging to 90% and the battery is doing just fine. The original Model S firmware didn’t even let you charge to less than 92%.

 

[gavine]

And watch your estimate of range get out of whack. Why are some people insistent on ignoring the experience of six years of Model S use? Many if not most of the early owners have been routinely charging to 90% and the battery is doing just fine. The original Model S firmware didn’t even let you charge to less than 92%.

So why did they start allowing it then? Must be a reason to put in the effort to make the change. Other than battery longevity, what other reason would there be to charge less than 90%?

 

[TexasEV]

So why did they start allowing it then? Must be a reason to put in the effort to make the change. Other than battery longevity, what other reason would there be to charge less than 90%?

The slider was introduced to get around the stupid EPA policy of averaging the advertised range if there were two settings (daily and trip). This happened to the Leaf. With a slider there aren’t two settings to advertise and Tesla could use the 100% range as the range. Search “slider” for many posts about this back in 2013 or 2014. Also it allows 50% charge for long term storage.

No one is saying there wouldn’t be a statistically significant difference in capacity after many years of different charge levels. It just hasn’t been shown to be a meaningful difference in how anyone would use the car. Would a 1 or 2% difference in range have any practical consequence for you in driving a 250 or 300 mile range car? If it would, someone bought the wrong car.

 

[gavine]

The slider was introduced to get around the stupid EPA policy of averaging the advertised range if there were two settings (daily and trip). This happened to the Leaf. With a slider there aren’t two settings to advertise and Tesla could use the 100% range as the range. Search “slider” for many posts about this back in 2013 or 2014. Also it allows 50% charge for long term storage.

No one is saying there wouldn’t be a statistically significant difference in capacity after many years of different charge levels. It just hasn’t been shown to be a meaningful difference in how anyone would use the car. Would a 1 or 2% difference in range have any practical consequence for you in driving a 250 or 300 mile range car? If it would, someone bought the wrong car.

Thanks for the insight. It's smart that Tesla allows a 100% charge if needed and warns you to not do it often. At least you can use that extra 10% for long trips as an option but most people don't need a full 100% daily. Kudos to Tesla on that.

 

[Eno Deb]

And watch your estimate of range get out of whack.

I've been charging to 70% daily (with occasional higher charges for trips) and my range estimate is spot on.

Also it allows 50% charge for long term storage.

Here's something I never understood: a lot of cars just stand around 90+ percent of the time (many people only commute for an hour or two on most days). Why is a lower daily SoC beneficial for "long term storage" but not for normal use, which isn't really much different from "storage" for this group of people?

No one is saying there wouldn’t be a statistically significant difference in capacity after many years of different charge levels. It just hasn’t been shown to be a meaningful difference in how anyone would use the car. Would a 1 or 2% difference in range have any practical consequence for you in driving a 250 or 300 mile range car? If it would, someone bought the wrong car.

The fact of the matter is that no one outside of Tesla has sufficient data to conclude how much impact it has. Maybe it's 1 or 2%, or maybe it's 5 or 10. On the other hand, we know that battery researchers and Musk himself recommend 70-80% ...

 

[Rocky_H]

If you use 20% daily, my recommendation would be 45-65% or 50-70%.

And watch your estimate of range get out of whack.

I'm pretty sure that's not how that works.
The estimator gets off if you have a small band of usage, regardless of whether that's nearer the middle or the top. So 45-65% or 70-90% would both cause the estimate to get out of whack. It needs to experience seeing how much energy it takes in that big transition from the low to high ends to "true up" that estimator to the real capacity. In other words, it needs to be able to "see" what low and high states are, and neither of those cases is letting it see low.