Model 3 Performance Battery Degradation One Month (Story)

[MP3Mike]

Logic tells us that both RWD and P3D can't get the same 310 range with different Wh/mi rating and same battery size. Therefore, there must be something setting that determines if the battery is a RWD or AWD/P, so that the AWD/P is effectively bigger to achieve the 310 mile range in the AWD/P (i.e. battery softtware limited in the RWD).

Is this plausible?

No there is only one battery size, and I highly doubt there is any software locking of any of it.

What we don't know is if Tesla applies a different rated range metric to a P3D+ than a P3D- or RWD. (We know that the AWD and P3D- get about 12% less range than a RWD Model 3, a P3D+ would get even less than that because of the wheels/tires.)

And again the range is listed as 310 for the RWD Model 3 because Tesla asked it to be reduced to that. (The range is reported artificially lower than it would be if you used actual test results/calculations.)

 

[TexasEV]

While most EVs take into account the driving history including the Model S and X this changed with the 3. Personally I like it but that is my preference.

And while it seems wheels make a difference (the aero wheels give about 15 more miles 5%) the range estimates do not account for it.

This is incorrect. The Model S and X only takes driving history into account on the energy app when displaying “projected range” based on past 5, 15, or 30 miles of driving. It does NOT take driving history into account when displaying rated range on the battery meter. That’s EPA rated range. Period. This is why the projected range on the energy app gives a different result than what the range on the battery meter shows.

 

[brianman]

Perhaps opening a can of worms, but in the interests of crowd-sourcing a theory...

You will see small changes in range as the vehicle processes your driving style. You can see this range go up and down depending on what features, options, and driving style. We have seen ranges go down by a few miles due to customers using quick accelerations from stops, higher speeds of travel, etc. The Tesla will analyze the driving style and adjust to give you a more accurate range. Some customers have changed driving styles and what features they use and seen an increase in range as well.

I suspect there are two things going on:
1. Misunderstanding among some Tesla employees that do believe that the rated range conversion for energy units to range is affected by driving history. I'm not sure where this notion originated, but I understand it to be explicitly incorrect for S, X, and 3. (I can't speak authoritatively about original Roadster but I believe the same rules apply here.)
2. The description above could be talking about the estimated energy available, which is subject to a variety of factors including driving style, climate (temperature and precipitation), elevation (air pressure), charging habits (cycling frequency, depth, typical SOC range, etc.). The "better than guess-o-meter" logic that evaluates available energy in the pack likely does produce different results affected by all of those factors -- again, including driving style -- which leads to a different rated range "for the same vehicle configuration and age" even though the energy-to-miles conversion factor is fixed/constant.

Elaborating on 2...
If drivers A and B take delivery of the same configuration on the same day and then part ways but happen to drive exactly the same number of miles before meeting up for lunch a month later, they may have different ranges reported at 90% by the UI in the cars. If you swapped the packs between the two cars and "did the appropriate things" (I have no idea the recommended process) to trigger recalibration, the reported ranges would likely swap for the two vehicles -- i.e. driving history doesn't affect the "expected efficiency" of the vehicle, but rather than "baked in" wear of the battery pack itself.

 

[D3xDt3Reaction]

Are any P3D owners getting 310 or better at 100% like those on What was the range for your first full charge??? Or are most P3D owners getting around 290?

 

[SigNC]

seems like most are around 295ish

 

[Nocturnal]

I hit right at 300 when charged to 100%. 3800 miles. Only charged to 100% twice, 2 supercharger uses, 1 track day. I don't think this has changed for me yet.

 

[JeffnReno]

Talked to Tesla software tech at the Gigafactory for about a half hour today and feel very good now about what I learned. After hearing about my charging patterns, logged battery levels, and driving experiences plus my time owning a Leaf and a Prius, he had me try some recommendations that others here may want to try. First he said that my short daily drives of 5-40 miles and then charging back to 70% can stop. He recommends only plugging in when I get down to maybe 100 miles range before charging back to 70-80%. Next he recommends running the car down to about 10 miles of range and charging back to 100% once a month. He wants me to take the car off a scheduled start time as it will prevent the car from using line power after reaching the set charge limit until the next charge time. That would explain why my range dropped while still plugged in. He said theymay address that in an OTA update in the future. We talked about several reasons foe these recommendations but most of my own problem sound self induced without meaning to.

 

[FSKT]

Talked to Tesla software tech at the Gigafactory for about a half hour today and feel very good now about what I learned. After hearing about my charging patterns, logged battery levels, and driving experiences plus my time owning a Leaf and a Prius, he had me try some recommendations that others here may want to try. First he said that my short daily drives of 5-40 miles and then charging back to 70% can stop. He recommends only plugging in when I get down to maybe 100 miles range before charging back to 70-80%. Next he recommends running the car down to about 10 miles of range and charging back to 100% once a month. He wants me to take the car off a scheduled start time as it will prevent the car from using line power after reaching the set charge limit until the next charge time. That would explain why my range dropped while still plugged in. He said theymay address that in an OTA update in the future. We talked about several reasons foe these recommendations but most of my own problem sound self induced without meaning to.

Honestly, I don't know what to believe about best practices.

It's all over the map, including what Tesla employees will tell you.

Does this Tesla software tech at the Gigafactory really know what he's talking about? Maybe. But I just don't know. I've heard conflicting stuff from different service center techs, about a host of things, either directly myself or from what I've read around the internets. Also, even on this issue, the manual says to always plug in every day, and this widely regarded battery expert (Dahn), whom I believe is employed by Tesla, says charge to 70% daily: “I would recommend charging to 70% normally. When you need a long trip, charge to 100%.” (Tesla battery expert recommends daily charging limit to optimize durability).

I have no doubt that this Gigafactory person told you what you say they told you, but it's hard to know if they truly have correct info, or what to actually do with so much different / differing info out there.

Personally, I just charge to 75-ish% every day and leave it at that, mostly following the recommendation of that Dahn person, in the cite above. Who knows, though . . . .

 

[VT_EE]

Both cars rage estimates are based on 310 miles at 100% battery capacity, it doesn't matter what the EPA test results were.

310 for the RWD is a BS number that Tesla asked the EPA to use. RWD has 130mpge, AWD has 116mpge. Explain how you can have different efficiencies, same battery, and same range. The RWD was sandbagged as documented in many threads relating to published EPA documents.

 

[D3xDt3Reaction]

He wants me to take the car off a scheduled start time as it will prevent the car from using line power after reaching the set charge limit until the next charge time.

Not sure I understand this advice. If I get in the car and crank the A/C while plugged in, I can get the car to pull power from the line even after it is charged. Same goes for scheduled charge (see image with car pulling 10A from line). Also, as others have alluded I thought it was better to stay plugged in to condition the battery?

 

[D3xDt3Reaction]

I hit right at 300 when charged to 100%. 3800 miles. Only charged to 100% twice, 2 supercharger uses, 1 track day. I don't think this has changed for me yet.

P3D+ or P3D-? Wondering whether tires have any impact.

 

[TT97]

310 for the RWD is a BS number that Tesla asked the EPA to use. RWD has 130mpge, AWD has 116mpge. Explain how you can have different efficiencies, same battery, and same range. The RWD was sandbagged as documented in many threads relating to published EPA documents.

I don't disagree. I believe RWD with 18" is closer to 332-334 mi. EPA, however, if the battery were to degrade 5% (taking it to 315 miles EPA), the range estimate will only show 294 miles when charged 100%, it doesn't matter that the EPA estimate would still be over 310 miles. If you are comparing battery degradation of the RWD vs the P, the range estimate will be the same the two cars if the battery degradation is the same - there is no buffer on the RWD models.

 

[D3xDt3Reaction]

Does this Tesla software tech at the Gigafactory really know what he's talking about?

The manual contradicts most of what he stated.

 

[Vines]

Are any P3D owners getting 310 or better at 100% like those on What was the range for your first full charge??? Or are most P3D owners getting around 290?

My first charge to 100% gave me 309 miles of range, after about 300 miles on the odometer. Supercharged twice since I have had the car, I only plug in at work.

 

[D3xDt3Reaction]

My first charge to 100% gave me 309 miles of range, after about 300 miles on the odometer. Supercharged twice since I have had the car, I only plug in at work.

Thanks for the info. P3D+?

 

[Vines]

Thanks for the info. P3D+?

Yep, like my Sig says

 

[Tommy Bahama]

P3D+, supercharged the other day. 303 miles@98%. Interpolates to around 310 @100%.

Lifetime wh/mi is a little less than 300, but lots of “fun” driving in there. Drove “normal” the other day and got in the 260 wh/mi neighborhood. So it would probably take some careful driving to turn a full charge into 310 real world miles, but it’s not too far off.

 

[JeffnReno]

Not sure I understand this advice. If I get in the car and crank the A/C while plugged in, I can get the car to pull power from the line even after it is charged. Same goes for scheduled charge (see image with car pulling 10A from line). Also, as others have alluded I thought it was better to stay plugged in to condition the battery?

I haven't tried experimenting with it yet but I couldn't tell from your picture if you were plugged in at the location where your schedule charge was set and if it had reached the charge limit for that day that was scheduled so wouldn't charge again until the next schedule. If all that is true, then maybe there are exceptions to what we discussed when it comes to starting the AC from the app while plugged in. I was just trying to relay what we discussed. I know the car will begin charging when I'm not at the location that the scheduled charge is set for.

 

[JeffnReno]

Honestly, I don't know what to believe about best practices.

It's all over the map, including what Tesla employees will tell you.

Does this Tesla software tech at the Gigafactory really know what he's talking about? Maybe. But I just don't know. I've heard conflicting stuff from different service center techs, about a host of things, either directly myself or from what I've read around the internets. Also, even on this issue, the manual says to always plug in every day, and this widely regarded battery expert (Dahn), whom I believe is employed by Tesla, says charge to 70% daily: “I would recommend charging to 70% normally. When you need a long trip, charge to 100%.” (Tesla battery expert recommends daily charging limit to optimize durability).

I have no doubt that this Gigafactory person told you what you say they told you, but it's hard to know if they truly have correct info, or what to actually do with so much different / differing info out there.

Personally, I just charge to 75-ish% every day and leave it at that, mostly following the recommendation of that Dahn person, in the cite above. Who knows, though . . . .

Maybe he just thinks he knows (the guy I spoke with) but it made since when he was explaining the reasons behind it to me and don't think he would knowingly advise me to do anything that would hurt my car. At this point, I feel what do I have to lose by trying his advice and if it works, great, and if not I probably won't be any worse off for the effort. I even brought up the advice in the owners manual and how all the forums repeat that a happy Tesla is a plugged in Tesla but he said that the Model 3 is so new and the cells are different so everyone including them are still learning as we go.

 

[SunCharged]

@EvilCowPow, has there been any update to your status?

I've compiled a lit of users with >5% degradation from this thread, and a thread that is on the tesla.com forum, just for reference. These are users with cars with relatively low miles. While I understand degradation is faster in the early miles, 5% so early seems excessive. I know I never was able to charge past 295 when it was brand new.

The numbers seem to be pretty consistent at about 260 miles@90% and 290 miles@100%, which makes me think that just one cell is going bad in packs. If it was simply degradation I would think our numbers would be a little more diverse.


EvilCowPow, 90% 263,
Dannno, 90% 260,
RyanF, 90% 263
D3xDt3Reaction, 100% 291
stonelance, 90% 263
doubleatheman, 100% 282

tesla.com forum
ANTHONYROSEJR, 100% 290
Charg3d, 100% 290
fskott, 100% 291

I just charged from 9 miles of range left to full overnight and ended up at 302 miles. As I’ve started typing this it’s already dropped to 299. Car is still plugged in.