Range Loss Over Time, What Can Be Expected, Efficiency, How to Maintain Battery Health

[Candleflame]

Was about to say the same. Never heard of a 2019 showing more than 500km range

they had a patch which increased the range back up to 523km or whatever it was for 2018/early 2019 AWDs i think.
The thing is of course is that you get immediate degradation now so noone actually gets that unless they havnt had a BMS calibration yet (i.e. car just sitting at 60% all the time)

 

[AlanSubie4Life]

they had a patch which increased the range back up to 523km or whatever it was for 2018/early 2019 AWDs i think.
The thing is of course is that you get immediate degradation now so noone actually gets that unless they havnt had a BMS calibration yet (i.e. car just sitting at 60% all the time)

No, that was for the RWDs only.

LR RWD: 325mi 523km (up from original 310mi, increased degradation threshold to 76kWh AFAIK, and may have unlocked capacity from ~72.5kWh (hard to know without contemporaneous captures). Constant did not change in any case.)
AWD 2018-2019: 310mi 500km (77.8kWh, degradation threshold 76kWh)
AWD 2020: 322mi 518km (77.8kWh, 77.8kWh threshold)
AWD 2021: 353mi 568km (in the US) ( 77.8kWh, later batteries "82.1kWh" (79-80kWh) degradation threshold still at 77.8kWh)

 

[Lephturn]

The take-away for me is that for my Sept. 2021 M3SR+ (not LFP) the thing I can do to impact degradation is to manage SoC that it spends the most time sitting at idle with a lower SoC. That means I use scheduled charging so that it charges to the SoC I need before I drive it. If I don't need extra range I charge to 55% so that my average SoC is below that spike in the degradation charts. The exception is cold temperatures with a Lvl 1 or low amp Lvl 2 as it will take so long to warm the battery if it's cold soaked to -20 C that it is best to charge it part of the way when I have just finished my driving and the battery is warm. When it is that cold and I am below 30% SoC I will plug it in (free Lvl 2 charger very close to my GF's place) and have it charge to 55% in the evening, then schedule charging and a scheduled departure for 8am and move the charge limit up to whatever I need. I normally charge it before I drive so that when I reach my destination it will sit at or below 55%. This means I can happily charge it to higher SoC when needed, and the side benefit is that if I schedule the charging properly and schedule it to prepare the car so the battery is warmed up and ready when I leave. Having the cabin warm, windows defrosted, and the seat and steering wheel heaters on when I get in is just amazing.

The good news is it's not a big issue. If I need to SuC I do it. If I need 80, 90, or 100% I do it, I just try to charge above 55% right before I drive it. I don't have a regular commute so most of my time is spent between 20-55% SoC when sitting.

The other thing I have learned is to leave the battery display in % and don't worry about it. If I have to drive more than 200k unexpectedly I can easily get to a Supercharger within 15 minutes and charge up to whatever level I need. I am lucky that in my area (Ottawa, Ontario, Canada) there seem to always be spots available to charge when I need it.

For anyone who is in my city, the free level 2 charger I use is at the International Brotherhood of Electrical Workers building on Canotek near the 174 and Montreal Road. They have a 2 slot charger on the West side of the building that will do 6 kw and a second 2 slot that will do 7 kw on the East side of the building. I rarely see anyone else charging there and it's always available and free.

 

[Nujec]

I'm trying to get some idea of how rare Model 3 battery failures and severe degradation are though the oldest Model 3 cars are still only halfway through the battery warranty period. I'm not expecting this to be common but would be interesting to know in light of Model S battery failure reports.

For the purposes of this poll I'm more interested in severe battery pack issues potentially needing traction battery pack replacement rather than failures that are much cheaper to fix such as failed charge port ECU (I had one of these replaced under warranty a few months ago) or 12v battery failures.

Please post more details including costs if you've needed a battery replacement or know of particular cases where a battery was replaced.

Although Tesla are probably not yet saying how much an out of warranty replacement battery costs there must be a few people who've had accident damage to the battery. It would be interesting to know if insurers have automatically written off cars with damaged battery packs.

 

[Tenannerz]

I have a M3 with 3k miles that originally had a charge limit of 253mi that I got at the end of August last year. Im currently charging it and the charge limit is 233mi. Im curious at to how or why it could drop nearly 8% in a few months, even though i was able to charge to the full 253 back in Nov. I know temperature effects the batteries, and its currently 10* here. Just last week, when it was in the mid 20s low 30s, it was around 245mi. Would temperature impact the charge limit that much? When warmer weather rolls around could I expect my battery to go back to its original range or at least close to it? Thanks in advance.

 

[Jo060]

Temperature has a great effect. Search around the forums on this exact question. There will be more information than you can take in.

 

[Nujec]

I'm trying to get some idea of how rare Model 3 battery failures and severe degradation are though the oldest Model 3 cars are still only halfway through the battery warranty period. I'm not expecting this to be common but would be interesting to know in light of Model S battery failure reports.

For the purposes of this poll I'm more interested in severe battery pack issues potentially needing traction battery pack replacement rather than failures that are much cheaper to fix such as failed charge port ECU (I had one of these replaced under warranty a few months ago) or 12v battery failures.

Please post more details including costs if you've needed a battery replacement or know of particular cases where a battery was replaced.

Although Tesla are probably not yet saying how much an out of warranty replacement battery costs there must be a few people who've had accident damage to the battery. It would be interesting to know if insurers have automatically written off cars with damaged battery packs.

This thread that my post got moved to is mostly about battery degradation and range estimation which is a different issue to battery replacements.

 

[CarlThompson]

As I understand it, it is ideal to keep a lithium-ion battery as close to 50% as possible.

I'm curious why you think 50% is some sort of magic number? Is it simply because it's halfway between 0 and 100% so it sounds good to you? I have read absolutely nothing to suggest that 50% is better for either long term storage or to maximize longevity vs. usefulness.

 

[AAKEE]

If I don't need extra range I charge to 55% so that my average SoC is below that spike in the degradation charts. The exception is cold temperatures with a Lvl 1 or low amp Lvl 2 as it will take so long to warm the battery if it's cold soaked to -20 C that it is best to charge it part of the way when I have just finished my driving and the battery is warm.

If its cold and you have the car outside, or in a not heated garage the calendar aging will be low even with SOC above the spike, as temperature is low. Temperature actually have a higher impact than SOC.
So when you need, if cold ambient, you can use higher SOC.

 

[AAKEE]

As I understand it, it is ideal to keep a lithium-ion battery as close to 50% as possible.

Nope.

50% is good, but not really because it is in the middle, its because it is on the right side of the step in calendar aging thats locsted at about 57 to 60%.

Calendar aging for a NCA Lithium ion battery(as used in Long Range model 3 and S/X And earlier model 3 SR) is lower the lower the SOC is. This as long the cell voltage is kept above 2.5V, which the BMS alwsys ensures.

This picture is from one research report, there is very many research reports telling us the same thing. The other picture from another report, telling us the same thing.

If you need to keep the decradstion low, keep the SOC low when the car is not in use. (And keep the battery cool, but thats most often not that easy to achieve).

I did follow this advice since my M3P was new one year ago(ODO 32000km now), and I still have full range when charging full.
I have several full charges and 17% Supercharging or so. Those do not hurt even close as much as having 80-90% all nights.
I also have a small benifit from living in a very high latitude( cold climate).

 

[AAKEE]

I am a remote worker and I use my Model 3 primarily for short drives (groceries etc). Most of my drives are less than 10 mins round trip.

My neighbor believes that because they are short drives and I still charge every night to keep it charged at 70% that it might have a negative effect on battery life.

I don't see the relationship between regular use and Tesla battery life.

Does anyone have any experience or thoughts on this?

Yes.

We know from the research that small cycles is good. The smaller the cycles, the longer the battery life will be( when it comes to cycles). Research use the term EFC, Equivalent Full Cycles( meaning 10 cycles with 10% dept = 1 EFC).

So you should charge every night if possible.

Calendar aging is causing the greatest degradation for most cars the first five years. Keepin the SOC low reduce the calendar aging. If you do not need 80% you could charge to 55%. Even better if this is done just before driving instead early in the evening(causing higher SOC all night).

These small cycles also cause much less wear if they are low in the SOC range.
6000 10% cycles(600 EFC) around 70% SOC (ie 75-65%) caused 10% degradation but 6000 10% cycles around 30% caused only 2-2.5%. Thats the same energy, same miles used but much less wear on the battery.

So:
-Stay low (55% or lower preferably)
-Charge “just in time”
-Charge often-> small cycles.

With these actions taken, the degradation will be very low, and one can happily Supercharge and charge to 100% when the need comes

 

[KenC]

This thread that my post got moved to is mostly about battery degradation and range estimation which is a different issue to battery replacements.

Having read thousands of posts, on this 3 forum, I think the number of instances of HV battery failure requiring any part of a pack to be replaced may be less than the fingers on one hand. You should check with the forum moderators, as they probably have read more posts. I used to have a 2016 Chevy Volt, and in the 3yrs I owned it, the forum I visited, there were definitely more battery packs replaced than in this 3 forum. Of course, it's all anecdotal, but HV pack replacement doesn't seem to be an issue. The probs seem mostly to be cosmetic and aesthetic ones, vs mechanical, though premature 12v battery failure seems fairly common.

 

[Moejoe]

Thanks

So best charging practice would be to 90%? Should I plug it in only once a day (after I’m done driving for the day) or whenever I can (every time I park it). Also reading controversies ideas on this.

 

[Apprunner]

So best charging practice would be to 90%? Should I plug it in only once a day (after I’m done driving for the day) or whenever I can (every time I park it). Also reading controversies ideas on this.

I think the best practice is the two posts prior to yours

The real answer is to do whats right for you and the range you need.

 

[jyavenard]

No, that was for the RWDs only.

LR RWD: 325mi 523km (up from original 310mi, increased degradation threshold to 76kWh AFAIK, and may have unlocked capacity from ~72.5kWh (hard to know without contemporaneous captures). Constant did not change in any case.)
AWD 2018-2019: 310mi 500km (77.8kWh, degradation threshold 76kWh)
degradation threshold still at 77.8kWh)

what is this degradation threshold you’re referring to?

77.8kWh in ScanMyTesla is the value of the battery capacity “when new”
70.6kWh is maximal capacity now showing (went down to just above 68kWh)

 

[jyavenard]

Nope.

50% is good, but not really because it is in the middle, its because it is on the right side of the step in calendar aging thats locsted at about 57 to 60%.

Calendar aging for a NCA Lithium ion battery(as used in Long Range model 3 and S/X And earlier model 3 SR) is lower the lower the SOC is. This as long the cell voltage is kept above 2.5V, which the BMS alwsys ensures.

This picture is from one research report, there is very many research reports telling us the same thing. The other picture from another report, telling us the same thing.

If you need to keep the decradstion low, keep the SOC low when the car is not in use. (And keep the battery cool, but thats most often not that easy to achieve).

View attachment 753117

I did follow this advice since my M3P was new one year ago(ODO 32000km now), and I still have full range when charging full.
I have several full charges and 17% Supercharging or so. Those do not hurt even close as much as having 80-90% all nights.
I also have a small benifit from living in a very high latitude( cold climate).

By those graphs, the best SoC to keep your car at are 0% or around. Which we all know is definitely incorrect.
So that makes me question the entire validity of them.
From reading most posts in this thread over the last 2 years, what you do to "preserve" the battery means bugger all. Everyone seems to have their own idea and is convinced it works better. Empirical evidence and all.

Tesla used to say to keep the car at 80% and over and charge as often as possible to let the BMS do its job. When you keep your car at 50% and lower it can't. It has no way to accurately determine the actual capacity of the battery. So you may think it's doing well, when it's not.

 

[frodebh]

From reading most posts in this thread over the last 2 years, what you do to "preserve" the battery means bugger all. Everyone seems to have their own idea and is convinced it works better. Empirical evidence and all.

No. Users on this forum like AAKEE above, have gotten the science around battery aging, degradation and expectations pretty much nailed down by now. There is broad consensus that keeping your car at a low SoC when resting is good. (Though different rules apply for the new LFP packs.)

 

[AAKEE]

By those graphs, the best SoC to keep your car at are 0% or around. Which we all know is definitely incorrect.


Tesla used to say to keep the car at 80% and over and charge as often as possible to let the BMS do its job. When you keep your car at 50% and lower it can't. It has no way to accurately determine the actual capacity of the battery. So you may think it's doing well, when it's not.

Well, the first bold is not correct. You might think we all know, but thats most probably a dunning krüger effect. I do not say this to be rude, but in a himble way because that most probably a fact.

Lithium ion batteries get the lowest calendar aging with low SOC.
There might be a different behaviour for the latest LFP-batteries used in the SR+, but I actually think they also degrade with high SOC just as all earlier LFP did. Ome can hope though.

The calendar aging dependence with SOC is the same in at least 50 research reports I have read in the subject, so this is facts.

Teslas recommendation is to not go above 90% daily, this is most probable due to the combination of high calendar aging, but most of all that you double the cycle life by reducing the charge level to 90% instead of 100%.
Teslas advice is of course set to not risk any high number of warranty due to degradation and still allow a as carefree ownership as possible. A lot of charging rules to get us the minimum degradation will not help tesla case because people would complain about ”I bought a LR but I got a SR” etc.
Tesla never said that 80% will make the degradation as low as possible.
Its all about what Tesla communicate and why.

I have used different lithium battery for very long time, and all chargers worth the name have a storage charge function. These set the charge level to a fixed voltage that is on the right side of high degradation thresholds, but still they keep as high SOC as possible for two reasons. Two have energy to allow for self drain during long time storage and to shorten the time to charge full for use.

My car regularly gets quite low SOC and I charge it full whenever I need. I had three full charges the last two months, and every now and then I need 80 or 90% and use that amount. My BMS might drift to show a little high but my “when needed” cycles show the battery capacity to calibrate the BMS. After 100% down to 3% after christmas my NFP went down from 81.4 to 80.4, which is the current NFP. The last few days I had two 80% charges dur to longer drives. Still 80.4, wich is about 505 to 506km range but if I charge to full it most probable will get nominal remaining about 0.3 to 0.5 kWh above the NFP, ad it aleays have done.

 

[conv90]

what is this degradation threshold you’re referring to?

77.8kWh in ScanMyTesla is the value of the battery capacity “when new”
70.6kWh is maximal capacity now showing (went down to just above 68kWh)

An example of a LR AWD 2018-2019: 310mi 500km at 100% SoC (77.8kWh full pack when new , degradation threshold =76kWh)
This means that the range expected stays the same (at max level example 500 km for a LR 2019) until the NFP stay over 76 kWh

If the car when new was 77.8kWh , the degradation strat immediately in a slow way : Say that after 1 month is at 77,00 kWh . It will continue to shows 500 km at 100% SoC.
another month of calendar aging of use? say that the NFP is 76,1? It will continue to shows 500 km at 100% SoC.

few months later when the capacity will be lower 76,00 kWh -example 75,5 kWh) , It will stops to shows 500 km at 100% SoC. but instead it will be ~495 km.

 

[robl45]

Model 3 performance 2019. Went 44 miles today and better saying 184 miles left. How much does it need to go to be at warranty level? Avg 288 watts or whatever. Just seems lower by the day and I hammer it