What Percent is Your Tesla Charged to While at Home?

[DB288]

let’s be realistic…tesla announced a new model 3…and with the same battery and motors it’s gets a nice bump in range just from aerodynamics…they probably modeled it with fluid dynamics with serious computing power…

the same for computer controlled battery charging…

how realistic it to google stuff on the internet and claim real expertise … 57%…really

a lot of the evidence is from 2017 paper discharging batteries in a lab…

there is serious engineering in these cars by teams professionals engineers…

 

[AAKEE]

let’s be realistic…tesla announced a new model 3…and with the same battery and motors it’s gets a nice bump in range just from aerodynamics…they probably modeled it with fluid dynamics with serious computing power…

the same for computer controlled battery charging…

how realistic it to google stuff on the internet and claim real expertise … 57%…really

I do not know anyone claiming expertise.
It is called science.

Do you have a better idea how to learn facts about batteries?

Should we continue to believe in the myths the science has showed is not true?
Earth still is flat to some people.

a lot of the evidence is from 2017 paper discharging batteries in a lab…

A lot of the evidence is from research reports from circa 2017 until today.
A lot = litterally hundreds of research reports.

The labs test storage in climate chambers with (different) controlled temperatures so we learn how temperature affect calendar aging.
Cycling tests is sometimes performed at cycles developed from real driving.
The sum of this is facts about hiw batteries behave and age.

there is serious engineering in these cars by teams professionals engineers…

It do not help being a very serious engineer, the batteries of today still will age like batteries of today.

Info from the serious enginers:

 

[DB288]

i disagree that it does not help to be a serious engineer?

listen it’s great that your enthusiastic and clearly love this stuff (as i do) and yes i am a being a bit of a gray haired @sshole…but these are really hard questions…

 

[kpanda17]

But we have to admit it’s amazing without some new revolutionary lith battery tech the profess/serious engineers have the new M3 LR at est 380-400 miles
Imagine when next gen batteries are applied

 

[AAKEE]

i disagree that it does not help to be a serious engineer?

In the same way your doctor can not stop you from aging, its not possible for the engineers to stop the batteries from aging by cyclic and calendar aging.
Its often refered to the BMS as a ’god’ for batteries. The BMS can even out the voltage differences between cells to make them wear even between cells.
But when you charge to X %, the BMS can only stand and measure things as the calendar aging happens.
If you charge to X % and drive down to Y%, causing a certain depth of discharge, the BMS only can stand by and look at things.
Cyclic aging will happen.

listen it’s great that your enthusiastic and clearly love this stuff (as i do) and yes i am a being a bit of a gray haired @sshole…but these are really hard questions…

I have an idea for a small experiment:

You tell me what Tesla you have. Model/year and:
-Location/average temp:
-Manufacturing month or purchase month
-Do you have a garage or is it parked outside?
-Charging level.
-What SOC (charging level) do you have after a normal day.
-When do you charge? Daily (?), at what time does it start.
-Odo reading.
-lifetime average consumption.

Then I use the sum of the science data to predict the capacity /range your car has, after the degradation with my formulas for that. So far it has not hit that wrong. Hardest thing is average cell tempersture, but I guess we can hit that not too far away.

If the science thing works (like the data from the research reports), its probable that the calculations also work and hit not too far from the real world.

 

[kpanda17]

Ok
-Model: 2023 MYP
-Location/average temp: NY Metro 57
-Manufacturing month or purchase month: Dec 2022
-Do you have a garage or is it parked outside? Park outside
-Charging level. 80% daily
-What SOC (charging level) do you have after a normal day. 63%
-When do you charge? Daily (?), at what time does it start. 1am
-Odo reading. 7771 miles
-lifetime average consumption 286

Do your calc please

 

[melvladimir]

with the same battery and motors it’s gets a nice bump in range just from aerodynamics

it’s amazing without some new revolutionary lith battery tech the profess/serious engineers have the new M3 LR at est 380-400 miles

I want to see the real field testing before I believe this statement. My M3LR 2022 has a range of 567 km (355 miles) and it is the real range at a speed of 100 km/h (and soon I'll try that, with AC on and some music. I need to travel 551 km).
They removed the side "air intakes" - I don't believe that they have such an impact. Also, they replaced tires and decreased top speed due to that. So, with all combinations, I can believe in +5..8% to range, which is traded off (I suspect tires are much less robust than mine Michelin Primacy 4+) but I don't believe in a 676 km range at a speed of 100 km/h! And this is with 75kWh battery! Not 82kWh! Let's tap on a calculator: 82kWh / 676 km range = 121Wh/km (137-121)/137 = 12% - this is huge jump, and for 75kWh / 676km = 111; (137-111)/137 = 19%! No way.
I suspect a marketing here.

 

[AAKEE]

Ok
-Model: 2023 MYP
-Location/average temp: NY Metro 57
-Manufacturing month or purchase month: Dec 2022
-Do you have a garage or is it parked outside? Park outside
-Charging level. 80% daily
-What SOC (charging level) do you have after a normal day. 63%
-When do you charge? Daily (?), at what time does it start. 1am
-Odo reading. 7771 miles
-lifetime average consumption 286

Do your calc please

Just put 25C average cell temp, it might be a little higher irl.
Estimation is made from 82.1 kWh Full Pack when New. capacity. I guess the time between manufacturing and delivery was not very long?

For the MYP i do not have the exact data for the degradation treshold or the charging constant.
Using 80,5 kWh as threshold (like the M3P) for 303 miles would give around 295 miles range at 100%.

To be sure, a energy screen calc would be best (If you do not have Scan my tesla).

Average x Calculated Range x 100 / SOC % = Watt hours.

 

[AAKEE]

i disagree that it does not help to be a serious engineer?

listen it’s great that your enthusiastic and clearly love this stuff (as i do) and yes i am a being a bit of a gray haired @sshole…but these are really hard questions…

Heres a anecdote:

Bought a model S Plaid.
It was built in the end of march.
Got it last june, so three months old from manufacturing date until I got it.

They have started to ship overseas with a lower SOC than before (Off-shore rules for lithium batt.)

I put the numbers in for that on the 99.4kWh Full pack when new, and found that it should be 98kWh at the time for delivery.
After the drive home, and connection of Scan My Tesla I saw 95.3 kWh nominal full pack. I “knew” it was too low.
The nominal full pack started to climb and soon I saw 98.0 ( well, 97.9-98.2 mostly).


For my M3P, it followed my graph set when I bought the car for the 2.5 years I had it.
I logged a lot of data and adjusted the average SOC and also average cell temp after the logged value.
The calculation said 78.0 kWh when I sold the car and the last nominal full pack I saw was 78.0 kWh (varied between 78.4-78.0 last months).

 

[flixden]

@AAKEE --- So how different would the outcome be if he would have charged to only 50%, and then discharged to 33%?

 

[AAKEE]

@AAKEE --- So how different would the outcome be if he would have charged to only 50%, and then discharged to 33%?

About cut the degradation in half.

My M3P still had 78.0 kWh after 2.5 yrs and 66K km.

 

[BigNick]

I have an idea for a small experiment:

2022 Model 3 Performance, Fremont-built.

Southern Pennsylvania, between Gettysburg and York. Statistics for Gettysburg:
Average high (July): 30.1C/86.2F
Average high (January): 4.2C/39.6F
Average low (July ): 17.1C/62.8F
Average low (January ): -6.2C/20.8F
Record high (July): 40C/104F
Record low (January): -32C/-25F

Built 2021-11-17, delivered 2021-12-04

Garaged. Temperature rangers from about 2C-5C in Winter and up to 35C-37C in Summer.

Charged to 50% as needed for local use, higher for long trips. Not charged daily. Can sit at low SoC for more than a week when not driven.

SoC after use ranges from 15% to 45%.

Charging scheduled for midnight to 02:00, but not charged daily.

6790 km (4220 miles) since new. I don’t drive much.

Lifetime consumption 158 Wh/km (255 Wh/mi). More local than highway.

It will be interesting to see the results.

 

[AAKEE]

2022 Model 3 Performance, Fremont-built.

Southern Pennsylvania, between Gettysburg and York. Statistics for Gettysburg:
Average high (July): 30.1C/86.2F
Average high (January): 4.2C/39.6F
Average low (July ): 17.1C/62.8F
Average low (January ): -6.2C/20.8F
Record high (July): 40C/104F
Record low (January): -32C/-25F

Built 2021-11-17, delivered 2021-12-04

Garaged. Temperature rangers from about 2C-5C in Winter and up to 35C-37C in Summer.

Charged to 50% as needed for local use, higher for long trips. Not charged daily. Can sit at low SoC for more than a week when not driven.

SoC after use ranges from 15% to 45%.

Charging scheduled for midnight to 02:00, but not charged daily.

6790 km (4220 miles) since new. I don’t drive much.

Lifetime consumption 158 Wh/km (255 Wh/mi). More local than highway.

It will be interesting to see the results.

The average SOC model is for daily but shows 31%, could this be about right har to judge from the description? (but it doesn't not matter much for the numbers)
The average ambient cas 12.2C for York so I took that number -> average cell temp about 20C. Could possibly be slightly lower.

As I had a M3P 2021 with the same range/battery, I know is started (should have) at 315 miles/507km.
Should be around 309 miles/ 497,5km range today.

 

[Edtreo]

2022 Model 3 Performance, Fremont-built.

Southern Pennsylvania, between Gettysburg and York. Statistics for Gettysburg:
Average high (July): 30.1C/86.2F
Average high (January): 4.2C/39.6F
Average low (July ): 17.1C/62.8F
Average low (January ): -6.2C/20.8F
Record high (July): 40C/104F
Record low (January): -32C/-25F

Built 2021-11-17, delivered 2021-12-04

Garaged. Temperature rangers from about 2C-5C in Winter and up to 35C-37C in Summer.

Charged to 50% as needed for local use, higher for long trips. Not charged daily. Can sit at low SoC for more than a week when not driven.

SoC after use ranges from 15% to 45%.

Charging scheduled for midnight to 02:00, but not charged daily.

6790 km (4220 miles) since new. I don’t drive much.

Lifetime consumption 158 Wh/km (255 Wh/mi). More local than highway.

It will be interesting to see the results.

Charge before leaving.

 

[Edtreo]

@AAKEE --- So how different would the outcome be if he would have charged to only 50%, and then discharged to 33%?

If that's an average usage of 20% I would do Max 30% and draw down to 10% or less before garaging. Then add 20% just before using it.

That's what I do. Since I can charge at work, I leave at <10%

 

[AAKEE]

If that's an average usage of 20% I would do Max 30% and draw down to 10% before garaging. Then add 20% just before using it.

I wouldnt, I would charge to 50%, as it is the lowest setting. (Of corse its possible to set the charging to start but the big win is staying at or under 55% (for NCA).

I do 55% even if 50% would be enough.
There is a plateau between about 30 and 55% with about the same calendar aging.

 

[Edtreo]

I wouldnt, I would charge to 50%, as it is the lowest setting. (Of corse its possible to set the charging to start but the big win is staying at or under 55% (for NCA).

I do 55% even if 50% would be enough.
There is a plateau between about 30 and 55% with about the same calendar aging.

I’m trying to keep the lowest energy possible overnight. It also gives me peace of mind that it has less chance of thermal runaway.

 

[zoomer0056]

thermal runaway

I'm wondering, Tesla has been around for 15 years. Has there been any reports of thermal run away?

 

[stopcrazypp]

I'm wondering, Tesla has been around for 15 years. Has there been any reports of thermal run away?

Only when the pack has been punctured or deformed in an accident. I'm not aware of any cases where the pack itself underwent thermal runaway from being parked undamaged.

During the Bolt recall (used as a sanity check example, given Bolts did undergo thermal runaway), GM/LG recommended avoiding both high AND low SOCs, but they never explained the reason for either limits.
GM And LG Are Working Around The Clock On Bolt EV Battery Recall

I didn't review all the cases of the Bolt fires, but it's not hard to find with a quick google that they occurred even with cars parked with low SOCs (this one was only at 34 miles indicated range, or about 14%).

https://www.reddit.com/r/BoltEV/comments/pf5tp3

I'm personally skeptical SOCs play that large a role in terms of sparking a fire. People seem to have the perception the fire energy is directly proportional to the SOC, but that's not the case. Even fully discharged the battery is still at ~274V, still plenty enough to short circuit (if there was an internal short) and cause a fire. Much of the thermal energy of the fire are from the battery materials themselves, which are flammable even if battery is fully discharged or at lower SOCs. The Bolt example above is the pretty good example of this coming into play.
What's the battery voltage from 0% to 100%?

 

[AAKEE]

The risk of fire without external damage is very low.

If you are in a crash, you might wanna prefer low SOC. Both lower risk to get a battery fire, and it is less powerfull with low SOC.
Just like the pilot’s say:
”Only time you have too much fuel is when on fire”.

I’d say you should’nt worry too much snout these things though.
Most people have been happily running around with a big gas tank before. More to burn with full tank, worse for explosion with low on fuel.