Charging everyday?

[TimothyHW3]

Question - Somewhat on topic. Since I’m still waiting for my SR+ (in week 6 now) I can’t figure out the following. I know you can set a departure time for your charging to finish so as not to hold a high soc for long. Can this setting be made “semi permanent “ so I can plug in ever night and not worry about having to reset it?

As a side note thinking about running an SR+ within 50% (30%-80%) of its max range while possible most days for me does add some anxiety.

Tesla has a newer update with some sort of smart schedule, but I am not sure what it is.

As for 30-80%, how many miles do you do a day, what is your weather in the area and at what speeds do you drive?
50% will give you realistic 120 or so miles(+/-) so if that is somewhat short you can consider 20%-90%. But if you can keep the car within 30-80% that will be better for battery and BMS. Give it a 100% charge once and again just to recalibrate the top.

20-90 does give more stress to the small battery, but this is unavoidable if you can't make it- this is the disadvantage of the SR+ - it racks more cycles for the same amount of miles as LR.

This is why Tesla only gives 100,000 miles warranty or so for the SR+

 

[lanbo]

I don't cycle 30-90. I try to cycle 30-40%-80%, but I also try to go to 10% and then back to 90% at least once a month, maybe even more.

I've been doing short trips of 30/40kms per day and then charge the car every night to 80/85%...

I decided to keep it at 80/85% just in case I had any emergency and because the Tesla policy is "always have the car plugged" so I felt that was the right thing to do.
In conclusion, my car has been for 7 months charged in a 70~85% SoC during 90% of the time (10,000 kms).

I hope I have not permanently damaged the battery as a result and I hope I only have a BMS miscalibration. BMS reports a 5.x % loss.
Maybe I have both BMS drift and some degradation too.

I've changed my charging habits to 30% -> 80%. I also plan to do 10%->90~95% once every couple of months.

 

[RayCanuck]

My SR+ has a 192000km/8yr warranty

 

[lanbo]

New theory:

I know one person that has been said in a SC that some cars are set to a higher Wh/km. He said 156 Wh/km but could not remember exactly.

Has anyone else received this information from a SC?

 

[TimothyHW3]

My SR+ has a 192000km/8yr warranty

Nope, All SR+ have 160,000km
Vehicle Warranty

You were probably missquoted by a rep. They are pretty missinformed.

New theory:

I know one person that has been said in a SC that some cars are set to a higher Wh/km. He said 156 Wh/km but could not remember exactly.

Has anyone else received this information from a SC?

Hardly possible and easily disprovable - just open your energy graph and see what the straight line says.

 

[lanbo]

Hardly possible and easily disprovable - just open your energy graph and see what the straight line says.

I've just measured my "typical" line.

My straight line is at approximately 156 Wh/km.
What should it be?

This is how I measured: I took a picture to the energy graph with the camera as flat as possible (so distortions & perspective are as small as possible).
Then I measured the pixels between 0 -> 200 and the pixels between 0->straight line.
Using rule of three I get 156.3 Wh/km (there is still possibly some error due to picture perspective/distortion but should not be large since the line at 200 is close to the "typical" line)

EDIT. This is surprising:
156 Wh/km * 500kms = 78kWh

Isn't the battery supposed to be 75kWh and 74kWh usable capacity?

EDIT2 The label for my straight line is "Typical" not "Rated".

 

[Rocky_H]

I know one person that has been said in a SC that some cars are set to a higher Wh/km. He said 156 Wh/km but could not remember exactly.

Yes, there is going to be a little bit of variation with the various model types, because they do have slightly different efficiencies based on weight differences, single or dual motor, performance or non-performance, etc.

Hardly possible and easily disprovable - just open your energy graph and see what the straight line says.

That's not a precise thing; it's a bit "snapped" to a round number for appearance purposes apparently. For all versions of the Model S, that line always looked like it was at "300 Wh per mile", but the real efficiency constants internally varied a bit a little above or below that. S75, P85, P85D, P90D, etc. etc. won't all have that exact 300 Wh per mile efficiency constant, but that's where the line always appeared to be on the energy graph.

 

[TimothyHW3]

New theory:

I know one person that has been said in a SC that some cars are set to a higher Wh/km. He said 156 Wh/km but could not remember exactly.

Has anyone else received this information from a SC?

Yes, there is going to be a little bit of variation with the various model types, because they do have slightly different efficiencies based on weight differences, single or dual motor, performance or non-performance, etc.

Ok, now that I read what he said I am not sure what he meant - that "some cars (same model and variant, as in same Model 3 AWD) have this typical and the same model car with same configuration have other typical wh/km
OR
that "some cars" in general as in: some Teslas have different Wh/km.

The first is obviously not true, the second is obviously true, but that is common knowledge so I didn't consider him meaning that...

 

[Kiwiadventure]

Nope, All SR+ have 160,000km
Vehicle Warranty

You were probably missquoted by a rep. They are pretty missinformed.


Hardly possible and easily disprovable - just open your energy graph and see what the straight line says.

My Model 3 SR+ has a 192,000km battery warranty in writing from Tesla.

 

[TimothyHW3]

My Model 3 SR+ has a 192,000km battery warranty in writing from Tesla.

Can you post it here?

 

[AlanSubie4Life]

My straight line is at approximately 156 Wh/km.
What should it be?

That's correct for an AWD.

EDIT. This is surprising:
156 Wh/km * 500kms = 78kWh

Isn't the battery supposed to be 75kWh and 74kWh usable capacity?

No. There are CAN bus readbacks I've seen showing 77-78kWh (including the buffer) for a brand new car. In the EPA test they discharged 79.2kWh https://iaspub.epa.gov/otaqpub/display_file.jsp?docid=46585&flag=1 from the battery (but keep in mind these may not be the same kWh - there is no reason the BMS needs to read true kWh, and it would have to be calibrated to match the calibrated equipment in Tesla's EPA measuring lab, anyway).

Furthermore, you'll never actually be able to draw the full 77-78kWh, because that would require driving until the battery is completely dead and the car stops moving, and the last 20km of draw would need to be conducted at very low consumption levels so as not to droop the battery into automatic shutdown.

Finally, while ultimately 156Wh/rkm*500rkm = 78kWh is probably no coincidence, it is a bit misleading. And again, 156Wh/rkm is NOT what is used for that (not too useful) Energy Consumption screen. (153Wh/rkm is used)

Specifically it is misleading because each rated km you use will show up on the trip meter as no greater than ~146Wh/rkm. So if you travel far enough to use 100 rated km on the battery gauge, you'll see no more than 14.6kWh on the trip meter. And it may be as low 14.2kWh. This means you have at most 73kWh (500 rated km - assuming you can get to that * 146Wh/km available for use as shown on the trip meter, before you get to 0 rated kilometers (and from there - if you get there - you would have to rely on using the buffer at a very low output power).

It's also misleading because at high SoC, the projections turn out to imply that you must fully use the buffer to get the predicted range. Whereas at very low SoC, the projected range, you will find, appears to show projections assuming nearly zero entry into the buffer. This behavior is just a function of the 153Wh/rkm constant being used for the projection, whereas actually you can do no better than 146Wh/rkm. Easy to test this claim out yourself. In some ways this behavior is good, but it does cause confusion.

You can check out my current summary/tracking here (which is subject to change if errors are pointed out - I did play fast and loose with Wh and kWh, so be careful about that):

Model 3 Lines & Constants Pre 36.1