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

[DrChaos]

What is your max traveled distance you have ever achieved on a single charge based on the energy graph?

San Diego to Los Angeles round trip. 22 M3LR. 260+ physical miles. Two segments, one stop. Started 100%, ended about 13%, but I don't remember exactly. Average OC/LA freeway traffic. Very pleased with freeway efficiency, better than my old BMW i3 which had tiny skinny tires and a much smaller battery and less weight.

From your graph it looks like you have lots of small stops & trips, and you drive fast and went uphill net. There are standby losses (uses energy), high climate losses (car probably heated up and blasted AC when you got in) and heavy foot losses. If you go on a long drive and don't go too fast you will get much better efficiency.

 

[RedY23]

The range loss from calendar degradation is highest the first year and slows down after that. Its 303 miles new. 285 is slightly higher degradation that I would expect (and there is some inaccuracy in the BMS) but not a sign of any obvious major defect.

Model Y P is not so efficient, being a Y (vs 3--this is the 3 forum) and especially a P with inefficient wheels and tires. So 29.7 kW/100 miles is slightly better than EPA efficiency (which does include charging losses of 5% or so and your measurement doesn't) of 30 kWh/100 mi.

From the numbers you give there doesn't seem to be anything wrong with your car. If you need range, switch wheels and tires to something more efficient.

Thanks for the imput. Sry didnt realize this was a M3 post. I dont need more range was just curious. I love those fat tires and the acceleration. I will enter the service mode on the tesla menu and do one of those 24 hour battery tests. But all is green there so far.

Love this forum and the ability to see how the other cars fare!!

 

[Tom Sagrak]

Regardless, you should recharge at every chance you get. It won't have any effect on the Wh/mile but helps with battery longevity.

Sorry, but i do not agree. If someone does a 10 or so mile a day, it's best to go to about 20% and then to recharge to 50%.
It's easier and better to the battery. Low SOC is better than a lot of charging.

 

[D Good]

Hello. I want to start this off by saying that I understand these cars and I get that the batteries don't last forever, etc etc. However, I know that the media tends to be saying that these cars don't have batteries that degrade that much. From these articles, I was expecting about 4-8 percent in the first year and then for it to level off.

I have a 2021 refresh (but not the 82 kWh battery) long range model 3, that has about 35k miles on it. Today, I finally got the chance to test for myself what the degradation would be; no more Tessie guess-o-meter. I would be taking this car from 100 to zero in one trip at ~75 mph with ac off, etc.

I knew things were bad when I reached 50%, I had only pulled 32 kWh for a 64 kWh total. Not even close to the ~75kwh the battery supposedly had to start with.
When it hit zero, I had pulled 63KWh from the battery in total. Comparing that to 75KWh gives me a whopping 16 percent degradation. Oh my God.

The car is not abused. About a third of its charging is done supercharging, the rest level 1 or 2. It does sit outside, but it is in the shade in the relatively mild North Carolina climate. I know Bjorn put out a video a few weeks ago that showed a 2021 with significant degradation. Could these cars have issues? Maybe.

Is anyone else experiencing anything like this? I expected this car to last at least 100k miles. Also, yes, I feel the degradation. That 100-0 trip was only 206 miles. The car is also horribly inefficient now since I got Michelin Pilot Sport All season 4s on it. 340 wh/mile at 78 mph. I used to get 290 on the old mxm4s.

The good news is that I'll be ditching this thing pretty soon for a highland. Can't wait for the extra efficiency and range from the slightly larger battery.

 

[AlanSubie4Life]

Hello. I want to start this off by saying that I understand these cars and I get that the batteries don't last forever, etc etc. However, I know that the media tends to be saying that these cars don't have batteries that degrade that much. From these articles, I was expecting about 4-8 percent in the first year and then for it to level off.

I have a 2021 refresh (but not the 82 kWh battery) long range model 3, that has about 35k miles on it. Today, I finally got the chance to test for myself what the degradation would be; no more Tessie guess-o-meter. I would be taking this car from 100 to zero in one trip at ~75 mph with ac off, etc.

I knew things were bad when I reached 50%, I had only pulled 32 kWh for a 64 kWh total. Not even close to the ~75kwh the battery supposedly had to start with.
When it hit zero, I had pulled 63KWh from the battery in total. Comparing that to 75KWh gives me a whopping 16 percent degradation. Oh my God.

The car is not abused. About a third of its charging is done supercharging, the rest level 1 or 2. It does sit outside, but it is in the shade in the relatively mild North Carolina climate. I know Bjorn put out a video a few weeks ago that showed a 2021 with significant degradation. Could these cars have issues? Maybe.

Is anyone else experiencing anything like this? I expected this car to last at least 100k miles. Also, yes, I feel the degradation. That 100-0 trip was only 206 miles. The car is also horribly inefficient now since I got Michelin Pilot Sport All season 4s on it. 340 wh/mile at 78 mph. I used to get 290 on the old mxm4s.

The good news is that I'll be ditching this thing pretty soon for a highland. Can't wait for the extra efficiency and range from the slightly larger battery.

This was a good test! Wen you say you did it in one trip, I'm assuming you did not stop at all (any energy used while parked is not counted and it can be significant).

So you have the vehicle with 353 rated miles of range to start with most likely. That one started with 353 rated miles.

Note that between 100% and 0% only includes 95.5% of your pack energy. So you need to account for that.

So your pack capacity is roughly: 63kWh/0.955 = 66kWh. So that's 15% capacity loss.

You can also just use the energy screen method, or your rated miles at 100%, to confirm. Since you started with 353 rated miles, you should now have 300 rated miles at a full charge. (That would be 15% loss.).

If that number does not align and your rated miles at 100% is higher, then your metering was probably wrong in some way (or your BMS is overestimating your capacity).

The good news is that I'll be ditching this thing pretty soon for a highland.

If you want to slow down capacity loss (and it sounds like you would prefer that), consider storing your car at around 55% or lower. Only if it is convenient, of course. You can charge far higher, of course, that doesn't matter much at all. Just leave it sitting at 55% or lower when possible.

 

[D Good]

This was a good test! Wen you say you did it in one trip, I'm assuming you did not stop at all (any energy used while parked is not counted and it can be significant).

So you have the vehicle with 353 rated miles of range to start with most likely. That one started with 353 rated miles.

Note that between 100% and 0% only includes 95.5% of your pack energy. So you need to account for that.

So your pack capacity is roughly: 63kWh/0.955 = 66kWh. So that's 15% capacity loss.

You can also just use the energy screen method, or your rated miles at 100%, to confirm. Since you started with 353 rated miles, you should now have 300 rated miles at a full charge. (That would be 15% loss.).

If that number does not align and your rated miles at 100% is higher, then your metering was probably wrong in some way (or your BMS is overestimating your capacity).


If you want to slow down capacity loss (and it sounds like you would prefer that), consider storing your car at around 55% or lower. Only if it is convenient, of course. You can charge far higher, of course, that doesn't matter much at all. Just leave it sitting at 55% or lower when possible.

I did the trip with no stopping at all. Man, 15 percent over 35k miles is just crazy. I get 317 miles reported at full (however this only happened recently, it hung around 329 for a long time but now it is tanking).
When I first got the car I was much less knowledgeable about all these things. I know when I bought the car they were advertising 353miles, but I don’t remember if the car ever reported that at 100%.

Overall, I am quite disappointed with what I have seen with this car with regards to degradation. Don’t get me wrong, I love the car, but I never expected in a million years that 15% of my battery would just vanish after 2 years. This is crazy.
There needs to be more research into designing batteries that don’t degrade. From what I hear, LFP doesn’t degrade as much?

 

[AlanSubie4Life]

I did the trip with no stopping at all. Man, 15 percent over 35k miles is just crazy. I get 317 miles reported at full (however this only happened recently, it hung around 329 for a long time but now it is tanking).
When I first got the car I was much less knowledgeable about all these things. I know when I bought the car they were advertising 353miles, but I don’t remember if the car ever reported that at 100%.

Overall, I am quite disappointed with what I have seen with this car with regards to degradation. Don’t get me wrong, I love the car, but I never expected in a million years that 15% of my battery would just vanish after 2 years. This is crazy.
There needs to be more research into designing batteries that don’t degrade. From what I hear, LFP doesn’t degrade as much?

So I am not sure what happened with your metering, but you should try it again. It is possible the BMS is over-estimating, but this seems like a large error.

317rmi implies 317/353*77.8kWh = 69.9kWh. Metering 100% to 0% should have yielded 66.7kWh so somehow you lost 3.7kWh in your metering. 1% discrepancy is common, but 4%+ is not.

So that is 10%.

Anyway looks like you care about capacity loss. Probably can be reduced a bit by keeping the car close to 55% or below most of the time. If you care. If it works for you.

I get 317 miles reported at full (however this only happened recently, it hung around 329 for a long time but now it is tanking

Large steps like this are common.

From what I hear, LFP doesn’t degrade as much?

It’s not that different. Loses capacity as well (check the threads on this). It can be stored a little bit higher SOC though as compared to NCA, without excessive calendar aging.

 

[Jejunjm]

For your interest, nfp 71.2, new pack 82.1, battery health 93%. 28k miles mostly charged level 2, some supercharging.

 

[Roger Nation]

My model 3 Performance is only getting about $147 Mi to a 80% charge in Sport mode. is this normal.

 

[Apprunner]

My model 3 Performance is only getting about $147 Mi to a 80% charge in Sport mode. is this normal.

147 miles on 80% real world range or the mileage indicator?

 

[RayK]

My model 3 Performance is only getting about $147 Mi to a 80% charge in Sport mode. is this normal.

I would say it all depends on how heavy your right foot is and how often it gets applied to the "Go" pedal.

 

[Sophias_dad]

I would say it all depends on how heavy your right foot is and how often it gets applied to the "Go" pedal.

And don't forget what they might be towing!

 

[bibena]

Tried searching for this but didn't find an exact answer to this battery health question: I know it's generally frowned upon to charge up to 100% unless you are either a) using an LFP battery, or b) charging for a road trip.

With that said, I tend to charge my 22 M3P up to 100% once every two weeks with no other charges in between. A charge up to 100% lasts me two full weeks. I know its been discussed ocassionally charging up to 100% then draining down to a fairly low value helps the BMS get a wider range of SOC readings. Also, whenever I do charge I time it so the battery doesn't sit at a super low SOC or at 100% for an extended period of time.

Overall, Is that any worse or better for the battery than just charging up to 75-80% then topping off every few days? What about maxing at 75-80% then not recharging until around 20% a week later?

 

[DrChaos]

Tried searching for this but didn't find an exact answer to this battery health question: I know it's generally frowned upon to charge up to 100% unless you are either a) using an LFP battery, or b) charging for a road trip.

With that said, I tend to charge my 22 M3P up to 100% once every two weeks with no other charges in between. A charge up to 100% lasts me two full weeks. I know its been discussed ocassionally charging up to 100% then draining down to a fairly low value helps the BMS get a wider range of SOC readings. Also, whenever I do charge I time it so the battery doesn't sit at a super low SOC or at 100% for an extended period of time.

Overall, Is that any worse or better for the battery than just charging up to 75-80% then topping off every few days? What about maxing at 75-80% then not recharging until around 20% a week later?

whatever has the least amount of time on average above 55%.

 

[AlanSubie4Life]

Tried searching for this but didn't find an exact answer to this battery health question: I know it's generally frowned upon to charge up to 100% unless you are either a) using an LFP battery, or b) charging for a road trip.

With that said, I tend to charge my 22 M3P up to 100% once every two weeks with no other charges in between. A charge up to 100% lasts me two full weeks. I know its been discussed ocassionally charging up to 100% then draining down to a fairly low value helps the BMS get a wider range of SOC readings. Also, whenever I do charge I time it so the battery doesn't sit at a super low SOC or at 100% for an extended period of time.

Overall, Is that any worse or better for the battery than just charging up to 75-80% then topping off every few days? What about maxing at 75-80% then not recharging until around 20% a week later?

In general the lowest time-averaged SOC, with substantial extra weight provided to SOCs under 55%, provides the least capacity loss over time, particularly when temperatures are high.

And lower cycling depth (charging more frequently), as long as it doesn't raise the SOC so a lot of time is spent above about 55%, seems better. But this is much less important. So just keep the time-averaged SOC low as mentioned above.

 

[nicksp]

My 18 M3LR has been supercharged often and to 100%. A full charge shows 296 miles.

 

[AlanSubie4Life]

My 18 M3LR has been supercharged often and to 100%. A full charge shows 296 miles.

So 11% loss assuming it is a RWD. 69.3kWh.

 

[nicksp]

So 11% loss assuming it is a RWD. 69.3kWh.

Yeah. RWD. I don't know if there are studies that directly compare battery degradation between 80, 90 and 100% charging. I've talked to a few owners who have no choice but to supercharge to 100% and they don't report any less range than those charging to 80%.

 

[AAKEE]

Yeah. RWD. I don't know if there are studies that directly compare battery degradation between 80, 90 and 100% charging. I've talked to a few owners who have no choice but to supercharge to 100% and they don't report any less range than those charging to 80%.

That is because the statement that ”100% is very bad” is a forum myth.

100% ( high SOC and maybe larger cycles) will cause slightly more cyclic aging in the long run than 80% and smaller cycles.

For calendar aging, 80-90-100% do not differ much. The calendar aging is higher at 100% when the temperature is very high but not extremely higher.

 

[DrChaos]

Yeah. RWD. I don't know if there are studies that directly compare battery degradation between 80, 90 and 100% charging. I've talked to a few owners who have no choice but to supercharge to 100% and they don't report any less range than those charging to 80%.

your average SOC is probably fairly low---do you not have home charging?