SMT Results

[vashwood]

Finally was able to purchase a data cable and a ODBlink. This is for a 2014 Model S 85 ~154k miles. Version: 2022.8.10.16. Based on what I've been reading, I think everything looks good? Am I missing anything?

SOC: 77.6%
Nominal Full Pack: 71.1 kWh
CAC min: 209 Ah
CAC max: 210 Ah
CAC imbalance (Ah): 1.90 Ah
CAC imbalance (%): 0.48%
Cell Volt Max: 3.954 V
Cell Volt Min: 3.940 V
Cell imbalance: 14 mV

 

[aerodyne]

Finally was able to purchase a data cable and a ODBlink. This is for a 2014 Model S 85 ~154k miles. Version: 2022.8.10.16. Based on what I've been reading, I think everything looks good? Am I missing anything?

SOC: 77.6%
Nominal Full Pack: 71.1 kWh
CAC min: 209 Ah
CAC max: 210 Ah
CAC imbalance (Ah): 1.90 Ah
CAC imbalance (%): 0.48%
Cell Volt Max: 3.954 V
Cell Volt Min: 3.940 V
Cell imbalance: 14 mV

I had a "15 85D. Ran SMT for a few years.

Looks good except for CAC. Which is excellent, better than my current '22MS LR

 

[vashwood]

Thanks for the feedback! should I also take measurements at a different SOC? or is this good enough for now? My main objective is to check if I need to worry about anything before upgrading to MCU2.

 

[aerodyne]

Thanks for the feedback! should I also take measurements at a different SOC? or is this good enough for now? My main objective is to check if I need to worry about anything before upgrading to MCU2.

Not needed.

Yes.

There is a chance MCU2 will mess things up, but it won't affect the pack or charging.

 

[scgaskill]

Just got a cable and downloaded SMT app and was pleasantly surprised my cheap $8 BT OBD II adapter actually works with it! Here are the results I captured from my 2014 MS60 with 44.4K miles. More to follow...

 

[scgaskill]

A few more. How does this look? I don't know how to interpret this data yet so any feedback greatly appreciated!

 

[ResHacker]

Finally was able to purchase a data cable and a ODBlink. This is for a 2014 Model S 85 ~154k miles. Version: 2022.8.10.16. Based on what I've been reading, I think everything looks good? Am I missing anything?

SOC: 77.6%
Nominal Full Pack: 71.1 kWh
CAC min: 209 Ah
CAC max: 210 Ah
CAC imbalance (Ah): 1.90 Ah
CAC imbalance (%): 0.48%
Cell Volt Max: 3.954 V
Cell Volt Min: 3.940 V
Cell imbalance: 14 mV

Hello there, is it really an 85kWh pack? For such a big amount of charged MWh it's insanely good! Enjoy your pack!

 

[ran349]

A few more. How does this look? I don't know how to interpret this data yet so any feedback greatly appreciated!

Thanks for sharing the data. Also, it's good that you showed the ALL tab since it shows the complete data set.

Your battery certainly appears to be in good shape, at least capacity wise. You have 55.3 kWh nominal full pack which represents the total battery capacity.
As a comparison, my 2015 70D, has very close to 55 kWh also, so I have a lot more degradation than you. But my odometer is at about 170k miles now.

You cell voltage imbalance is 4 mv, which is also excellent for your older battery. My imbalance is 20 to 25 mv now.

You have a 2.8 kWh buffer, while the larger batteries from the legacy cars, including my 70D, all had a 4.0 kWh buffer.

Did you happen to know what the car was reporting for SOC and rated miles at the time you took this data? You can see there are different SOC calculations in the SMT data, and I was try to use that to calculate you conversion constant your car uses to convert the 55.3 kWh number to rated miles that get displayed by the car. The three methods used to calculate were all different, giving 71%, 72%, or 73%. So only one of those would have been matching the car reading.

If you capture this data again, could you also read the car displayed SOC %, and rated miles at the same time for comparison?

The only thing I see that seems a little off is your driving efficiency number, which also comes directly from the car. Is your driving efficiency really close to 343 Wh/mi? That seems a little bit high, My car lifetime is at 291 Wh/mi, and on the freeway I do better than that.

 

[scgaskill]

Thanks for the info! I believe my SOC was 71% and the milage 44,421. Yeah the efficiency isn't great. I drove the car for several months before I decided to start paying attention to the Wh/mi. Most of my driving is city driving and I don't have a good average. When I get out on the tollway at 65-75 mph it'll be around 315 Wh/mile but varies of course.

 

[scgaskill]

A week ago I charged it to 98% which showed an estimated 190 miles. It's at 68% now with 132 est miles

 

[scgaskill]

Thanks for sharing the data. Also, it's good that you showed the ALL tab since it shows the complete data set.

Your battery certainly appears to be in good shape, at least capacity wise. You have 55.3 kWh nominal full pack which represents the total battery capacity.
As a comparison, my 2015 70D, has very close to 55 kWh also, so I have a lot more degradation than you. But my odometer is at about 170k miles now.

You cell voltage imbalance is 4 mv, which is also excellent for your older battery. My imbalance is 20 to 25 mv now.

You have a 2.8 kWh buffer, while the larger batteries from the legacy cars, including my 70D, all had a 4.0 kWh buffer.

Did you happen to know what the car was reporting for SOC and rated miles at the time you took this data? You can see there are different SOC calculations in the SMT data, and I was try to use that to calculate you conversion constant your car uses to convert the 55.3 kWh number to rated miles that get displayed by the car. The three methods used to calculate were all different, giving 71%, 72%, or 73%. So only one of those would have been matching the car reading.

If you capture this data again, could you also read the car displayed SOC %, and rated miles at the same time for comparison?

The only thing I see that seems a little off is your driving efficiency number, which also comes directly from the car. Is your driving efficiency really close to 343 Wh/mi? That seems a little bit high, My car lifetime is at 291 Wh/mi, and on the freeway I do better than that.

So is the total battery capacity 55kW nom + 2.8 kW buffer = 57.8 kW total, down from 60kW new, thus 3.7% degradation? From what I've read the 60, 70, 75, 85 kW numbers are rounded up marketing numbers so I don't think my pack was a full 60 kW even when new.

I've been using the estimated milage now vs new to determine degradation up to now. 194 miles at 100% SOC now vs 208 miles originally rated for 6.7% degradation, which seems more realistic.

 

[ResHacker]

So is the total battery capacity 55kW nom + 2.8 kW buffer = 57.8 kW total, down from 60kW new, thus 3.7% degradation? From what I've read the 60, 70, 75, 85 kW numbers are rounded up marketing numbers so I don't think my pack was a full 60 kW even when new.

I've been using the estimated milage now vs new to determine degradation up to now. 194 miles at 100% SOC now vs 208 miles originally rated for 6.7% degradation, which seems more realistic.

It actually was as those smaller packs were much closer to their advertised capacity than their bigger counterparts (85 or 90kWh).

 

[ran349]

So is the total battery capacity 55kW nom + 2.8 kW buffer = 57.8 kW total, down from 60kW new, thus 3.7% degradation? From what I've read the 60, 70, 75, 85 kW numbers are rounded up marketing numbers so I don't think my pack was a full 60 kW even when new.

I've been using the estimated milage now vs new to determine degradation up to now. 194 miles at 100% SOC now vs 208 miles originally rated for 6.7% degradation, which seems more realistic.

No, your actual capacity of 55.3 kWh includes the buffer. So If your conversion constant is 286 Wh/mi ( it could be 285 or 287 also), then your degradation would be 55.3/.286/208 = about 7%. That equals what you calculated and is excellent for your battery at this stage.
It looks like your original battery had about 59.5 kWh, which makes sense.