Is it better for my car to spend more time at 50% or have shallower discharge cycles but spend more time at a higher state of charge.

[jefferrrson]

It has been the Panasonic 82.1 kWh before but the recent 2024 EPA test showed only 78.8-78.9 kWh was delivered from the pack (both LR and P).
This indicate a change, as the Panasonic pack always delivered 80.7-82.1 kWh before.
It is possible (logical) that they changed to the LG NMC/NMCA packs with 78.8-79kWh capacity in the Y as well, for the same reason as in the 3.
View attachment 1032175

It need to be checked, preferably by looking on the battery label (info somewhere on TMC where to look, on 3 it can be seen by looking into the center of the car via the wheel well).

From a “preserving the battery” perspective its not a big issue:
Panasonic NCA is happiest below 55% displayed SOC and (LG) NMC below 60% so if you set 50 or 55% your safe.

I use 55% for the daily (model S, and model 3 before) as there is not really a difference between 50 and 55%, so 55% gives the max range at the same degradation.

Set it to 50-55% until you know. If you find out its the LG you can use 60% or below.

@ucmndd: Ping! this thread also covers the batt type, you might have more info on this?

Thanks for the reply! Would this also apply to LFP batteries?

 

[AAKEE]

Thanks for the reply! Would this also apply to LFP batteries?

LFP batteries is slightly different.
They can do large cycles very many times.
NMC/NCA will hold up for ~ 1000 cycles or so if cycled 100-0% but LFP can do several thousand of these 100-0%.
So there is no need to charge below 100% for the daily charging habit when it comes to cyclic aging.

They still degrade from calendar aging, and the “step” which it good to be below is at about 70% displayed SOC.
Calendar aging is about half below 70%, so if the cells are kept below that most of the time, total degradation is reduced.

This chart is not from the exact cells used in Teslas RWD cars but they seem to behave very similar. The exact position of the step could theoretically vary slightly.

 

[Usher]

LFP batteries is slightly different.
They can do large cycles very many times.
NMC/NCA will hold up for ~ 1000 cycles or so if cycled 100-0% but LFP can do several thousand of these 100-0%.
So there is no need to charge below 100% for the daily charging habit when it comes to cyclic aging.

They still degrade from calendar aging, and the “step” which it good to be below is at about 70% displayed SOC.
Calendar aging is about half below 70%, so if the cells are kept below that most of the time, total degradation is reduced.

Do you have a link to research papers where these charts seem to come from? I'm interested in reading more details on the test results.

 

[AAKEE]

Do you have a link to research papers where these charts seem to come from? I'm interested in reading more details on the test results.

I have regularly posted links to research.

Radware Bot Manager Captcha



https://mediatum.ub.tum.de/doc/1355829/document.pdf (yes, it is in english -read a bit further)
https://www.researchgate.net/journa...WQiLCJwcmV2aW91c1BhZ2UiOiJwdWJsaWNhdGlvbiJ9fQ
https://research.chalmers.se/publication/535926/file/535926_Fulltext.pdf






https://research.chalmers.se/publication/535926/file/535926_Fulltext.pdf

 

[AAKEE]

Heres a post with several good links:

charge everyday or once in 3 days

 

[AAKEE]

Link

 

[jefferrrson]

I have regularly posted links to research.

Radware Bot Manager Captcha



https://mediatum.ub.tum.de/doc/1355829/document.pdf (yes, it is in english -read a bit further)
https://www.researchgate.net/journa...WQiLCJwcmV2aW91c1BhZ2UiOiJwdWJsaWNhdGlvbiJ9fQ
https://research.chalmers.se/publication/535926/file/535926_Fulltext.pdf






https://research.chalmers.se/publication/535926/file/535926_Fulltext.pdf

thank you sir !! I’ll be reading these this weekend. These need to be publicized more. Might even do a YouTube video with this. Your next beer is on me! Or coffee.

 

[AAKEE]

thank you sir !! I’ll be reading these this weekend. These need to be publicized more. Might even do a YouTube video with this. Your next beer is on me! Or coffee.

Recommend reading several research reports.
You can find the reports yourself by searching for calendar aging/ cyclic aging / lithium ion and maybe specify with the chemistry you would like to read about.

Articles in EV-magazines is to 99% wrong and is lured by the myths.
Also, batteryuniversity has a lot of flaws in the material.
Go with real research reports, so you get it from the source direct.

 

[gottagofast]

Someone on Reddit said accelerating fast often esp in the performance model will degrade your battery much faster than just driving normally, because it heats up the battery in a short burst before it has a chance to cool

Is this true or something someone just made up

 

[E90alex]

Driving or using the car at all degrades the battery faster than leaving it parked.

 

[gottagofast]

Driving or using the car at all degrades the battery faster than leaving it parked.

Yes but he specifically said accelerating fast degrades it faster even more

Driving at a steady 80 mph degrades the battery less than accelerating 0 to 60 with the pedal to the floor is what he said

What’s your opinion on this @AAKEE

 

[AAKEE]

Yes but he specifically said accelerating fast degrades it faster even more


What’s your opinion on this @AAKEE

Well, cycles in general degrade the battery much less than time.

In general, higher current/power causes more wear than low current. Just like Supercharging causes more wear than home charging.

Lithium batteries can handle short bursts of high power much better than long sustained power.
This is for example you can have high power regen (100kW) at 80% SOC but you will not get 100kW charging power at 80% at the Supercharger.

A 0-60 run takes 1.9 ( ) to 5 seconds. That is a fairly short burst and will not hit the battery with noticable degradation.

Driving at autoban at top speed from 100% SOC until the car stops will cause noticaböe degradation if you do it several times. (On the other hand a high power ICE car engine also would notive some wear from this.

I did use 0-62mph and ~ 1/4 mile several/many times with my M3P during my 66K km / 2.5 years I had it.
Ended up with 492 km displayed range when the average on Teslafi was around 460-465km range.
Also, the EV seller company had several model 3 with the same battery as mine (82kWh), both LR and P). These cars was younger than mine (I had a very early 82kWh batt) and they had luch less miles. Still they showed 9–13% degradation in the battery test, where mine showed 5% (they use 82.1 kWh as the origin capacity).
These batteries most often reach 80.5-81kWh which makes the degradation number go down but also increases the difference between my M3P and the other.

So, If my M3P didnt show much degradation you should not worry

My Plaid is still quite new, (1 year from manuf. last sunday), I had 97.1 kWh nominal Full pack and reached 97.8 kWh Nominal remaining yesterday at a full charge which is about as good as most people see as the top value. My summer wheels (~8000 km) ate starting to see the end of life as I have used the 1020 hp, every one of these suckers, quite much
Again, normal ”fun” will not kill the battery.

Driving at a steady 80 mph degrades the battery less than accelerating 0 to 60 with the pedal to the floor is what he said

The question is impossible to answer, as the 80 mph steady has no description of the duration.

3.5s 0-60mph wears more than 3.5s at 80mph, if that was the question.

Still neglible, as we now know!

 

[gottagofast]

battery test, where mine showed 5% (they use 82.1 kWh as the origin capacity).
These batteries most often reach 80.5-81kWh which makes the degradation number go down

I didn’t know this, so some new performances will start off with 80.5 kWh instead of 82?

 

[AAKEE]

I didn’t know this, so some new performances will start off with 80.5 kWh instead of 82?

The battery is 82.1 kWh full pack when new, but has delivered 80.6-82.1 in the EPA tests.
Most cars BMS with this battery do not go above 80.5-81 as the top value.

( it is not important in the question for the cyclic aging, but more of a question how people calculate degradation, my car lost 3% range during 2.5 years and 66K km)

 

[gottagofast]

The battery is 82.1 kWh full pack when new, but has delivered 80.6-82.1 in the EPA tests.
Most cars BMS with this battery do not go above 80.5-81 as the top value.

( it is not important in the question for the cyclic aging, but more of a question how people calculate degradation, my car lost 3% range during 2.5 years and 66K km)

So a lot of times the epa range of a new performance could be displayed as 310-312 miles instead of 315 right when someone took delivery

 

[AAKEE]

So a lot of times the epa range of a new performance could be displayed as 310-312 miles instead of 315 right when someone took delivery

The car shows full range to about 80.5-80.7 kWh so most cars would start at 315 mi or very close.


Tesla use a degradation threshold, often ~2% lower than the full capacity.

For my Plaid, I still have full range (560km/348 mi) one year after manufacturing date, and 18K km.
My M3P held full range until 35K km and 1 year and ~ 3-4 months

 

[evfangirl]

@AAKEE For the LFP in the model 3 the screen in the car recommends charging to 100% once a week. I’m renting this standard range model 3 while I wait for mine to be built.

From what I’m reading here we should only go to 70% or less to minimize the degradation and also charge nightly if possible? Or let the battery run down to whatever is personally comfortable for range anxiety then charge back to 70%?

for the other battery for the model 3 read 55% instead of 70%

Thanks for this info.

I’ve ordered the long range M3 with the white interior but am waffling about maybe the LFP battery is a better choice. Since they haven’t started making the white interior yet, I have time to ponder which is the better battery choice. I generally drive around 120 miles a week. I’d appreciate some feedback.

Thanks.

 

[dafish]

Jax, obviously most of use feel aakee has a strong understanding on these issues. My own research agrees with his as well. One implication of this is to ignore those posts that contradict his guidance.

As to your need, I would only suggest dropping/lower the supercharge to arrive home at 50% since you’ll only use @10% before you charge again. I only supercharge as needed to get home with a mild (10%) reserve. If not too inconvenient I’d do that, charge to 40% at home, charge higher when needed for a trip.

Yep, I get that adds a charge hassle for you.

 

[AAKEE]

@AAKEE For the LFP in the model 3 the screen in the car recommends charging to 100% once a week. I’m renting this standard range model 3 while I wait for mine to be built.

View attachment 1039814

From what I’m reading here we should only go to 70% or less to minimize the degradation and also charge nightly if possible? Or let the battery run down to whatever is personally comfortable for range anxiety then charge back to 70%?

The LFP cars needs a full charge for the sake of giving the BMS a well defined point of energy in the battery.
The charging level/SOC is hard to measure on LFP batteries due to a very flat voltage curve. So if not charged full the BMS estimate of the SOC can drift.
If the BMS is wrong about the capacity, the car could stop before the calculated SOC is 0%.
The BMS increases the buffer (energy below 0%) as a safety measure when the BMS has not gotten a reset recently, this reduces the possible driving range until the car shows 0%.
So charging to 100% once a week or so is recommended.

for the other battery for the model 3 read 55% instead of 70%

55% or less for the Long range and Performance with Panasonic NCA chemistry.
60% or less for LG batteries with NNC/NMCA chemistry.
70% or less for LFP.

These values are from research with different chemistries, NCA is tested with Panasonic cells but a few years back. We also have newer tests supporting this.
For LG NMCA we can only assume that they behave about the same as the other brands of NMC cells in the tests. Because the LG cells is a NMC811 with a touch of aluminium added (4% I think) the exsct SOC value for the “step” could differ. I have several friends and also know about several cars via these forums that use the 60% or below with very good result (very low degradation) so we could be quite sure that 60% works well for the LG Pack.
You will most probably get a LG Pack in the new 3 LR.

Thanks for this info.

I’ve ordered the long range M3 with the white interior but am waffling about maybe the LFP battery is a better choice. Since they haven’t started making the white interior yet, I have time to ponder which is the better battery choice. I generally drive around 120 miles a week. I’d appreciate some feedback.

Thanks.

Its a matter of choice most people do on the cost basics.

If you do not feel the difference in cost is an issue, there really aren’t any drawback having a long range with 4wd/dual.

 

[evfangirl]

The LFP cars needs a full charge for the sake of giving the BMS a well defined point of energy in the battery.
The charging level/SOC is hard to measure on LFP batteries due to a very flat voltage curve. So if not charged full the BMS estimate of the SOC can drift.
If the BMS is wrong about the capacity, the car could stop before the calculated SOC is 0%.
The BMS increases the buffer (energy below 0%) as a safety measure when the BMS has not gotten a reset recently, this reduces the possible driving range until the car shows 0%.
So charging to 100% once a week or so is recommended.

55% or less for the Long range and Performance with Panasonic NCA chemistry.
60% or less for LG batteries with NNC/NMCA chemistry.
70% or less for LFP.

These values are from research with different chemistries, NCA is tested with Panasonic cells but a few years back. We also have newer tests supporting this.
For LG NMCA we can only assume that they behave about the same as the other brands of NMC cells in the tests. Because the LG cells is a NMC811 with a touch of aluminium added (4% I think) the exsct SOC value for the “step” could differ. I have several friends and also know about several cars via these forums that use the 60% or below with very good result (very low degradation) so we could be quite sure that 60% works well for the LG Pack.
You will most probably get a LG Pack in the new 3 LR.

Its a matter of choice most people do on the cost basics.

If you do not feel the difference in cost is an issue, there really aren’t any drawback having a long range with 4wd/dual.

Thank you so much for answering my questions. This really helps settle my battery anxiety.

The last question I have for the health of the battery, is it better to charge fewer times and let the battery run down to a low SoC or is it better to keep the car plugged in and charge daily? I’m thinking the answer might be different for the 2 types of batteries the LG and the LFP

Again thank you so much for your insight. I intend to keep this car for a long time and want to maximize its health. I’ve installed the home charger so I can do either easily.

Thanks