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

[jyavenard]

i lost another 3km. urgh. hope it's just imbalance from my 1.1k km drive.

Try charging to 100%, and let the car sleep at this level for a few hours.

 

[Candleflame]

Try charging to 100%, and let the car sleep at this level for a few hours.

i charged to 100% 2 days ago for my trip on a 3kw charger. There was definetely some imbalance as the car spent quite a bit of time at 100% (for over 30min it charged at 3kw (22 ratedkm/h) even though it actually only got 1km added. Normally by the time it gets to 99% its already down to 2kw.

The car didnt sleep though. I will do another roaddtrip in 3 weeks so i might charge to 100% until 0200 and then let it sleep for 3 hours. Doubt it will make much difference.

 

[Rhytid]

Can someone who knows more than I chime in on this, please?
Have 2020 P3D+ with 20 inch wheels. Have 28.5k miles.
Started with about 98% charge and drove 121 miles. Parked for about 5 hours (about 2 hours with sentry mode on, rest with sentry mode off). Cabin overheat OFF. Summon OFF. Then drove about 6-7 miles around 40-45 mph. Then drove back home.
Most of driving was highway and speed was set to 65 and then 70 mph.
Heat/AC off. Seat warmerWindows up.
Navigation was on. Bluetooth was on.
Speakers on. Wireless charging on.
So I am supposed to have somewhere around 75 kWh battery (let’s assume it’s more like 70 with degradation).
Where did all the extra Watt hours go?

 

[AlanSubie4Life]

, half of those miles are on the freeway at 75 mph, the other half is in the city for about 55 mph, it takes me from 25-30 mins to get there. After Taking it to work for more than a week now, I have come to realize that my commute uses 20%-22% energy from my battery for my 42 miles commute. So based on my calculations my car has a range of 210 miles,

If you're running Sentry at work that's a part of it.

These calculations imply a use on the car energy meter of about 0.22*77.8kWh*0.955/42mi = 390Wh/mi

That's definitely high, but 10 hours of Sentry mode would account for part of that (would mean driving is more like 350Wh/mi). This is still high though. I'd expect closer to 300Wh/mi unless you're blasting the heat or have a bicycle rack on the car or something like that.

I'd just post your Wh/mi for your commute here and then also note the % loss while you're sitting at work (so when you start work and when you depart work, how much energy are you using?

The most useful thing is just knowing your Wh/mi use. With that should be able to sort this out.

I'd expect more like 17% of your energy would be used for your commute, while actually driving, not 22%. Meaning a range of about 250 miles.

 

[KenC]

So I got my model 3 a week ago. I love everything about it. There's only one thing that concerns me. He has to do with the range. So I bought the model 3 "long range", because they advertise up to 353 Miles range. My daily commute is 21 miles, half of those miles are on the freeway at 75 mph, the other half is in the city for about 55 mph, it takes me from 25-30 mins to get there. After Taking it to work for more than a week now, I have come to realize that my commute uses 20%-22% energy from my battery for my 42 miles commute. So based on my calculations my car has a range of 210 miles, but like I said I bought it thinking it will be closer to 350 miles. No I do keep in mind the part of my commute is on the freeway at a higher speed which uses more energy, but that's only half of my commute. So where are the other 140 miles? Is my car range normal? Has anyone had a similar commute? I'm just trying to get some more insight before calling Tesla and making a fool out of myself.

We need more data, with pics. Show start screen, stop screen, what's your efficiency, etc. Asking people to guess with minimal datapoints is pretty much a waste of time.

 

[KenC]

You show you used 62kWh, and you've got 21 miles or 5kWh in the battery, so you show 67kWh total, not counting the kWh used in the 5 hrs parked. Easily could use 3+ miles of range with a mix of sentry on an off, so about 1kWh. That puts you at 68kWh, or about a 10% deg. Oh, forgot you started at 98%, so you have about 69kWh, or about 8% deg. I'm sure Alan or someone else can come up with something more precise, but either way, your 8% deg seems fairly normal for 28.5k miles.

 

[sospechoso14]

If you're running Sentry at work that's a part of it.

These calculations imply a use on the car energy meter of about 0.22*77.8kWh*0.955/42mi = 390Wh/mi

That's definitely high, but 10 hours of Sentry mode would account for part of that (would mean driving is more like 350Wh/mi). This is still high though. I'd expect closer to 300Wh/mi unless you're blasting the heat or have a bicycle rack on the car or something like that.

I'd just post your Wh/mi for your commute here and then also note the % loss while you're sitting at work (so when you start work and when you depart work, how much energy are you using?

The most useful thing is just knowing your Wh/mi use. With that should be able to sort this out.

I'd expect more like 17% of your energy would be used for your commute, while actually driving, not 22%. Meaning a range of about 250 miles.

So I dont use sentry mode at all. I’m not blasting the heat, but I do have my AC on, it’s 100 degreees weather where I live. I dont have any bicycles racks or anything like that and I have my aero caps on. My usual Wh/mi is 278 to 290 on my commute to work. I actually don’t waste energy at work, i get free charging there so I basically charge my car at work all the time, and not home. I waste about 1% of energy while the car is sitting at home during the day.

 

[sospechoso14]

If you're running Sentry at work that's a part of it.

These calculations imply a use on the car energy meter of about 0.22*77.8kWh*0.955/42mi = 390Wh/mi

That's definitely high, but 10 hours of Sentry mode would account for part of that (would mean driving is more like 350Wh/mi). This is still high though. I'd expect closer to 300Wh/mi unless you're blasting the heat or have a bicycle rack on the car or something like that.

I'd just post your Wh/mi for your commute here and then also note the % loss while you're sitting at work (so when you start work and when you depart work, how much energy are you using?

The most useful thing is just knowing your Wh/mi use. With that should be able to sort this out.

I'd expect more like 17% of your energy would be used for your commute, while actually driving, not 22%. Meaning a range of about 250 miles.

Thank you for replying btw

 

[sospechoso14]

We need more data, with pics. Show start screen, stop screen, what's your efficiency, etc. Asking people to guess with minimal datapoints is pretty much a waste of time.

I added some more info

 

[AlanSubie4Life]

So I dont use sentry mode at all. I’m not blasting the heat, but I do have my AC on, it’s 100 degreees weather where I live. I dont have any bicycles racks or anything like that and I have my aero caps on. My usual Wh/mi is 278 to 290 on my commute to work. I actually don’t waste energy at work, i get free charging there so I basically charge my car at work all the time, and not home. I waste about 1% of energy while the car is sitting at home during the day.

So unless you have lost a lot of capacity - easy to tell, just switch to miles and quote the value at a high % - something does not add up here.

For a brand new car, 280Wh/mi over 42 miles will give you (280Wh/mi*42mi)/(0.955*77.8kWh) = 16%

So you should be using 16%, and your car’s range with that sort of driving is about (0.955*77.8kWh/280Wh/mi) = 265 miles.

This (16%) would be perfectly normal. Your car with a rated range of 353 miles has a real-world freeway range of 225-275 miles. That is common knowledge and the way it works. On a road trip it will have a range of 150-200 miles between stops, for optimal trip time.

To get 353 miles to 0%, you need to hit 210Wh/mi usage, for the record. (See above calculation.). This is not possible on the freeway unless you are going downhill or have a strong tailwind.

Can you double check your use to/from work? Add some pictures of that specific trip (each way individually!) next time you do it (capture the actual Wh/mi for the journey and the % used). Should end up being 16% not 22%. It’s a large difference and it does not add up. (If you are REALLY using 22% of your capacity for 42 miles at 280Wh/mi, your vehicle has lost 28% of its battery capacity - which is extremely unlikely, and easy to determine by looking at your rated miles projected to 100%.)

 

[sospechoso14]

So unless you have lost a lot of capacity - easy to tell, just switch to miles and quote the value at a high % - something does not add up here.

For a brand new car, 280Wh/mi over 42 miles will give you (280Wh/mi*42mi)/(0.955*77.8kWh) = 16%

So you should be using 16%, and your car’s range with that sort of driving is about (0.955*77.8kWh/280Wh/mi) = 265 miles.

This is perfectly normal. Your car with a rated range of 353 miles has a real-world freeway range of 225-275 miles. That is common knowledge and the way it works. On a road trip it will have a range of 150-200 miles between stops, for optimal trip time.

To get 353 miles to 0%, you need to hit 210Wh/mi usage, for the record. (See above calculation.)

Can you double check your use to/from work? Add some pictures of that specific trip (each way individually!) next time you do it (capture the actual Wh/mi for the journey and the % used). Should end up being 16% not 22%. It’s a large difference and it does not add up. (If you are REALLY using 22% of your capacity for 42 miles at 280Wh/mi, your vehicle has lost 28% of its battery capacity - which is extremely unlikely, and easy to determine by looking at your rated miles projected to 100%.)

Thank you for all your insight. I will set a trip tomorrow to measure exactly how much I spend to get to work and back.

 

[AlanSubie4Life]

Thank you for all your insight. I will set a trip tomorrow to measure exactly how much I spend to get to work and back.

Great! Just remember the trip meter does not count use while you are in park. That’s why I suggested segmenting each direction and noting % (miles) before and after each segment.

 

[sospechoso14]

So unless you have lost a lot of capacity - easy to tell, just switch to miles and quote the value at a high % - something does not add up here.

For a brand new car, 280Wh/mi over 42 miles will give you (280Wh/mi*42mi)/(0.955*77.8kWh) = 16%

So you should be using 16%, and your car’s range with that sort of driving is about (0.955*77.8kWh/280Wh/mi) = 265 miles.

This (16%) would be perfectly normal. Your car with a rated range of 353 miles has a real-world freeway range of 225-275 miles. That is common knowledge and the way it works. On a road trip it will have a range of 150-200 miles between stops, for optimal trip time.

To get 353 miles to 0%, you need to hit 210Wh/mi usage, for the record. (See above calculation.). This is not possible on the freeway unless you are going downhill or have a strong tailwind.

Can you double check your use to/from work? Add some pictures of that specific trip (each way individually!) next time you do it (capture the actual Wh/mi for the journey and the % used). Should end up being 16% not 22%. It’s a large difference and it does not add up. (If you are REALLY using 22% of your capacity for 42 miles at 280Wh/mi, your vehicle has lost 28% of its battery capacity - which is extremely unlikely, and easy to determine by looking at your rated miles projected to 100%.)

Right now, after charging at work, it shows 240 miles at 68%

 

[AlanSubie4Life]

Right now, after charging at work, it shows 240 miles at 68%

Yeah so you are basically at full capacity of 353 miles as you would expect. 77.8kWh. So there’s no issue with your battery. This is just a question now of how much range you should expect and how to figure it out.

 

[sospechoso14]

Yeah so you are basically at full capacity of 353 miles as you would expect. 77.8kWh. So there’s no issue with your battery. This is just a question now of how much range you should expect and how to figure it out.

Thank you for sharing what you know with me. I will be posting each trip segment tomorrow

 

[Venomized]

Just supercharged to 100% and got 277 miles for my 2018 Model 3 Performance with 67k miles.

 

[happyguy]

So I got my model 3 a week ago. I love everything about it. There's only one thing that concerns me. He has to do with the range. So I bought the model 3 "long range", because they advertise up to 353 Miles range. My daily commute is 21 miles, half of those miles are on the freeway at 75 mph, the other half is in the city for about 55 mph, it takes me from 25-30 mins to get there. After Taking it to work for more than a week now, I have come to realize that my commute uses 20%-22% energy from my battery for my 42 miles commute. So based on my calculations my car has a range of 210 miles, but like I said I bought it thinking it will be closer to 350 miles. No I do keep in mind the part of my commute is on the freeway at a higher speed which uses more energy, but that's only half of my commute. So where are the other 140 miles? Is my car range normal? Has anyone had a similar commute? I'm just trying to get some more insight before calling Tesla and making a fool out of myself.

I have a similar commute. 23 miles one way. With my 2018 LR, I use 10% energy each way. Currently with 42K, 87% SOC gives me 248 miles. Tesla service center just finished running the battery diagnostic and found nothing abnormal. Recent trip from Sacramento to SF, 218.9 miles round trip used 51 kWh = 233 Wh/mi.

Still the best car purchase. NOT going back to ICE car.

 

[jyavenard]

Has their been any studies done on how well LFP batteries behave over time?

With Tesla recommending that you charged them to 100% at least once a week to keep the BMS properly calibrated, how much will they degrade over time?

 

[PhantomX]

Has their been any studies done on how well LFP batteries behave over time?

With Tesla recommending that you charged them to 100% at least once a week to keep the BMS properly calibrated, how much will they degrade over time?

I didn't realize we are supposed to do that. Was it in the manual or in Tesla's response to this battery issue? I have only charged to 100% a few times in the 2 years I owned the car. I typically charge to 90%. It would be good to know if I am supposed to charge it to 100% weekly.

 

[MP3Mike]

I didn't realize we are supposed to do that. Was it in the manual or in Tesla's response to this battery issue? I have only charged to 100% a few times in the 2 years I owned the car. I typically charge to 90%. It would be good to know if I am supposed to charge it to 100% weekly.

Do you have a MiC Model 3 with a LFP battery? (Unlikely if you are in California.)