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

[ShelJW]

From what I've read (I'm no expert), you're advised not to charge your car to 100%, unless you're going on a long drive, and in that situation, they recommend wait until right before you leave to top your battery off, then drive it to bring it below 100%..You're also advised not to bring the battery below 10% on a regular basis...

Also, Supercharging the battery on a regular basis also degrades the battery more quickly. Slow charging your battery to, say, 80-90% most days and recharging it before it gets very low will maintain your batteries health.

I'm sure your battery hasn't suffered major harm, but if you've only driven it 6,000 miles and have already drained it below 10% on a few occasions, and charged it to 100%, I'd suggest set it to charge at home at 80-85%, leave it and forget it.

My two cents.... (80-85% battery charge gives my MYP between 250-260 miles range, more then enough for daily driving, other then if I'm going on a long out of town trip)

 

[Theone8181]

Think yourself lucky, my 2019 model 3 performance has a range if 250 miles at 90% charge, not sure how accurate the estimation is though.

 

[804son]

Not all Variation in the range shown is battery degredation. Estimating the amount of energy in the pack is apparently tricky business. If I look at my teslafi battery report it jumps all over the place I have a high of 300 estimated miles of range to a low of 293. All of the long term reports I've seen actually show really good battery resilience to degradation. Switch to percentage and forget about it.

 

[jjrandorin]

Think yourself lucky, my 2019 model 3 performance has a range if 250 miles at 90% charge, not sure how accurate the estimation is though.

Thats like 7% degradation as performance are rated at 299 for 100% range with 20 inch tire (which is quite good).

 

[Theone8181]

Thats like 7% degradation as performance are rated at 299 for 100% range with 20 inch tire (which is quite good).

OK fair enough. What worries me is that the tyres aren't the most premium of brands so I'd expect to lose more range when I change them.

 

[Mino]

Thank you for all the replies, everyone. I do not charge my car past 90% I have charged it to 100% 3 times since I have had the car.

 

[AAKEE]

If I look at my teslafi battery report it jumps all over the place I have a high of 300 estimated miles of range to a low of 293.

Teslafi do not have access to the SOC otherwise than the whole percentage number. This means there will be a rounding error on teslafi that is in the order of 1% at high SOC and slightly more at low SOC.
I use both teslafi and scan my tesla + teslalogger.

The scan my tesla/teslalogger range is very stable, the nominal full pack perhaps change 0.1kWh os so during a week, making the range change less than a km.
At the same time teslafi shows a very ersttic behavior, but this comes from teslafi calculating the ”degradation”(full range) by dividing the current range with the rounded SOC number.

The nominal full pack and the cars real reported range is much closer to the teslalogger value

 

[AAKEE]

Hi everyone, so I read a lot about this I’ve tried many things but still car is not going back to normal. So I have a 2022 M3P started with 315 miles with 100% charge. When I first got it I used superchargers a lot however, after I moved I installed my own level two charger and I’ve been using that for the past month or so. I tried bringing the car down to single digits once at 3% once at 7% charged it to a 100%. Now the car shows me 303 miles sometimes it’ll go to 300 or 307 is the highest I’ve seen since. Is there anything else I can do? I know it’s only a 10 mile difference but the car has less than 6k miles on it. Thank you in advance for all the answers.

Supercharging is not that hard on model 3 batteries. The best approach is to let the car preheat the battery fully. If you only have 6K miles, even if most was Supercharging it wouldnt show any degradation from that part.

The dominant part of the degradation is the calendar aging, which is caused by Time x SOC x temperature.
About 3 - 10 % degradation from calendar aging is ”normal” depending on the climate and charging habits.

If you leave the car with about 80% SOC* most of the time your battery probably will degrade about 5% just from calendar aging the first year. Calendar aging reduces with time so it wont be as high further on.

Cyclic aging is most probably about 1% or less each year for a car driven about average mileage.

*80% just as an example.

Your 315 mi origin points to that the battery did start its life with “full” capacity( at least 80.7kWh).

The single point SOC you had did not degrade the battery. The lower SOC the less the battery degrade, both when cycled and when at rest.

If you regularly use high SOC, you will loose capacity in the order of 5% the first year. In a hot climate a little more, in a cold slightly less.
I do not know the normal SOC you charge to and the climate, but in a average climate you probably loose some 4% the first six months if using 70-90% SOC.
If we do the math from a full 82kWh battery you would be at about 78.5kWh after the first six months, this correlates to about 307 miles range.

 

[Steve446]

The scan my tesla/teslalogger range is very stable, the nominal full pack perhaps change 0.1kWh os so during a week, making the range change less than a km.
At the same time teslafi shows a very ersttic behavior, but this comes from teslafi calculating the ”degradation”(full range) by dividing the current range with the rounded SOC number.

The nominal full pack and the cars real reported range is much closer to the teslalogger value

I was very interested in finding a reliable parameter I could use for estimating "degradation". Referring only to my own car, SMT data for full rated range is much noisier than NFP. Since January 12, when I installed SMT, I looked at the Standard Deviation for these two data sets, there is almost a X10 difference between the two SDs (variation from the mean, 2.61 Km to 0.27 kWh). I also observed the same change in SD over several days when the car wasn't used ie no change in Odometer. So, NFP based comparisons seem to be the best bet for me.

These parameters are likely impacted by several other things such as temperature, driving, charging etc. When put on the same graph, both show a similar slope from the Jan 12 start apart from the variation. These data appear to agree with Teslalogger although I will admit that the time base in my case is much less than for their data. Anyhow, that's real geek stuff and I guess most people will be happy to use the range data as a guide

 

[AAKEE]

I was very interested in finding a reliable parameter I could use for estimating "degradation". Referring only to my own car, SMT data for full rated range is much noisier than NFP. Since January 12, when I installed SMT, I looked at the Standard Deviation for these two data sets, there is almost a X10 difference between the two SDs (variation from the mean, 2.61 Km to 0.27 kWh). I also observed the same change in SD over several days when the car wasn't used ie no change in Odometer. So, NFP based comparisons seem to be the best bet for me.

These parameters are likely impacted by several other things such as temperature, driving, charging etc. When put on the same graph, both show a similar slope from the Jan 12 start apart from the variation. These data appear to agree with Teslalogger although I will admit that the time base in my case is much less than for their data. Anyhow, that's real geek stuff and I guess most people will be happy to use the range data as a guide

Well, SMT also seem to calculate the Full range by multiplying the range with the SOC. Theres a variation but smaller than teslafi. I typically see 505 to 508km.
The teslafi range is usually lower and vary about the double 5-8 km between days is not unusual, this despite the NFP being the same.

The NFP is the best degradation parameter we have. The other calculations use NFP as the base, and also involve the SOC.

The range is calculated via the “charge constant. For my M3P 2021 it is 159Wh/km(rounded from 159.X as in 159.2 or so)

80.7 gives 507km/315 miles range.
80.700/159.2= 507km.

These values do not change with the temperature(but a cold battery might show lower SOC, people say).

Driving/charging/ambient temp do not change the range calculation.

 

[Steve446]

Well, SMT also seem to calculate the Full range by multiplying the range with the SOC. Theres a variation but smaller than teslafi. I typically see 505 to 508km.
The teslafi range is usually lower and vary about the double 5-8 km between days is not unusual, this despite the NFP being the same.

The NFP is the best degradation parameter we have. The other calculations use NFP as the base, and also involve the SOC.

The range is calculated via the “charge constant. For my M3P 2021 it is 159Wh/km(rounded from 159.X as in 159.2 or so)

80.7 gives 507km/315 miles range.
80.700/159.2= 507km.

These values do not change with the temperature(but a cold battery might show lower SOC, people say).

Driving/charging/ambient temp do not change the range calculation.

Agree, many errors clearly come from rounding. Your range values variation (505-508) likely fits with mine (~+/- 0.4 to 0.5%). Also it would interesting to know where the NFP calculation comes from? Thanks as ever for your challenges and observations.

 

[AAKEE]

Agree, many errors clearly come from rounding. Your range values variation (505-508) likely fits with mine (~+/- 0.4 to 0.5%). Also it would interesting to know where the NFP calculation comes from? Thanks as ever for your challenges and observations.

The Nominal Full Pack is the BMS estimate of the battery capacity. Its not a SMT inveted value.

So, NFP is Teslas battery enginers best guess of the battery actuall capacity.

SOC is determined by the resting Voltage of the pack ( a.k.a OCV ), when the car sleeps.
The BMS also measures the in- and out values of energy.

If the BMS know that the SOC is 50%, from a long sleep, and a charge to full measures 40kWh in to the battery, the capacity is 80kWh. (A little simplified but, yes).

 

[Alicehaydawn47]

So I have a Model 3 2021 Standard Range +.
I bought it brand new from Tesla in September last year, which means I’ve only had it for a little over 6 moths, and the car has around 7000kms on it.

I noticed when I was done charging the car to around 80% the range was at 307km, and when I tried to turn the charge limit up to a 100%, it said that 100% equals 375km?

So the car is supposed to have a range at 445km at 100%. Now I know it is normal to lose a little after having the car for a while, but is this much normal after such a small amount of time?
I usually try my best to make sure that I maintain the battery well by only charging to 80% each time and I’ve never super charged, only used my Tesla Wall connecter at home
The last time I charged to a 100% I managed to get around 435km (but that was back in November 2021), but now I literally get 70 km less.
- I’ve also waited the last week to se if the battery life went up by itself in case it had something to do with usage or weather, but it is still at 375 km when fully charged.

So, what do I do now?
Is this something worth requesting service from Tesla?
And will it go under any of the warranty’s I have with the car?

Thanks for any help

 

[AAKEE]

So I have a Model 3 2021 Standard Range +.
I bought it brand new from Tesla in September last year, which means I’ve only had it for a little over 6 moths, and the car has around 7000kms on it.

I noticed when I was done charging the car to around 80% the range was at 307km, and when I tried to turn the charge limit up to a 100%, it said that 100% equals 375km?

So the car is supposed to have a range at 445km at 100%. Now I know it is normal to lose a little after having the car for a while, but is this much normal after such a small amount of time?
I usually try my best to make sure that I maintain the battery well by only charging to 80% each time and I’ve never super charged, only used my Tesla Wall connecter at home
The last time I charged to a 100% I managed to get around 435km (but that was back in November 2021), but now I literally get 70 km less.
- I’ve also waited the last week to se if the battery life went up by itself in case it had something to do with usage or weather, but it is still at 375 km when fully charged.

So, what do I do now?
Is this something worth requesting service from Tesla?
And will it go under any of the warranty’s I have with the car?

Thanks for any help

You’re from Norway…

Theres a range of different batteries for the SR+
Do you know if you have the LFP battery or not? (The charge setting in the car, does it say up to 90% for daily and above 90% for trips?)

First of all, the mobile app do not show correct range readings all the time. Very often it shows to low range.
You need to check this up in the car.

If it is a car with a LFP battery, you should chsrge full once a week to help the bsttery management computer to keep the track pf the battery capacity.
The car will never show the WLTP range value on the screen at the battery symbol.
Tesla use the US EPA-rating as the base for the range.

There was one version of the 2021 SR+ with a WLTP of 448km, but that car will not show 448km on the screen. This car did show around 420km when new( because tesla show the EPA range and not WLTP).

If you keep the car at 80% SOC for the most of the time, the battery most probable will loose about 4-5% during the first year.

 

[Tam]

...So, what do I do now?...

Enjoy your car because it can hold a charge at least 70% of its listed capacity and not below.

You can open up a service ticket but I doubt that they will fix it while it is still at least at 70% capacity.

That's another reason to buy more range than you need to account for 30% capacity loss that is not covered by the warranty.

 

[nurusz]

Here the famous Norwegian fellow, Bjørn Nyland

 

[Destiny1701]

I have a Jan 2022 M3 LR (18” tires) with 578km t she when new…confirmed by first charge. I usually go 80% max down to perhaps 20% occasionally.

Today charged to 100% for a trip and stated 563 max range.

I guess this is normal 3 months in? Seems a bit much for a car that hasn’t one super charge and always max 80…no?

 

[Sophias_dad]

I have a Jan 2022 M3 LR (18” tires) with 578km t she when new…confirmed by first charge. I usually go 80% max down to perhaps 20% occasionally.

Today charged to 100% for a trip and stated 563 max range.

I guess this is normal 3 months in? Seems a bit much for a car that hasn’t one super charge and always max 80…no?

2.5% range loss? That's not even noise.

 

[Destiny1701]

2.5% range loss? That's not even noise.

Ah ok…could also be up here in Toronto we are still at 8-12c outside and it’s basing it on avg wh/km used in last few months

Just didn’t expect this while nursing it lol.

 

[AAKEE]

I have a Jan 2022 M3 LR (18” tires) with 578km t she when new…confirmed by first charge. I usually go 80% max down to perhaps 20% occasionally.

Today charged to 100% for a trip and stated 563 max range.

I guess this is normal 3 months in? Seems a bit much for a car that hasn’t one super charge and always max 80…no?

The biggest part of degradation comes from calendar aging. Cyclic aging, from charging and driving probably is less than 1% degradation per year. supercharging is mot that hard to the battery.

Calendar aging during normal average summer temperature and/or inhouse temps will cause about 5-6% the first year.
(Calendar aging reduces with time so it is not as bad as it might look).

For a 80% charge, with the car standing most of the time at 80% or so, you will have about 2-3% calendar aging dyring the first three months if the temperature is around 15-20degrees C (garage storage etc).
At lower temps( Canada outside during winter) you might cut that degradation in half.
So a degradation is expected but its too early to use the BMS value to be sure.
The BMS have a variation(noise as @Sophias_dad says) in the calculation of the actual capacity of the battery.

That said, 80% is NOT the sweetspot for low calendar aging.
But, the calendar aging reduces with time.
What you loose the first year need another three years to double, and after these four years you need another 12 years to double it again.