Best way to quantify loss of usable battery?

[Halodde]

I posted something similar previously but am now asking for feedback from the group on this subject particularly from those who have driven EVs for many years and those who have ties to Lucid. What is the best way to determine loss of usable battery accurately? The only information I have is the obvious data provided by the car displays. This morning, for example, I left the house at 100% and drove (on the highway) nonstop. When my range was at 50% remaining, the 'since last charge' reading displayed that I had used 40 kWh. Assuming the readings are accurate, this implies that my usable battery is only 80 kWh. If this is the case, I've lost about 13% of the initial usable 92 kWh.

So my follow up questions are:
1) Is this the best way to quantify the loss?
2) Does anyone know if this is how Lucid calculates loss of battery capacity as it applies to the warranty?

Thanks in advance for your input.

 

[borski]

Post in thread 'Solar for Charging Purposes'
https://lucidowners.com/threads/solar-for-charging-purposes.7864/post-185446

 

[Halodde]

Post in thread 'Solar for Charging Purposes'
https://lucidowners.com/threads/solar-for-charging-purposes.7864/post-185446

Thank you very much. I will admit most of that content was way over my head. But when I get to sit down at a computer I'll take a look at it and see if even a dimwit like me can figure it out

 

[DeaneG]

Thank you very much. I will admit most of that content was way over my head. But when I get to sit down at a computer I'll take a look at it and see if even a dimwit like me can figure it out

Just go to https://testmycode.cc/ and enter your lucidmotors login and password. It's very straightforward.

 

[Halodde]

Just go to https://testmycode.cc/ and enter your lucidmotors login and password. It's very straightforward.

Excellent. I'd say there's at least a 50% chance I can manage that

 

[SaratogaLefty]

Also since you live in Buffalo it might be the cold weather is impacting your estimated usage.

 

[Halodde]

Also since you live in Buffalo it might be the cold weather is impacting your estimated usage.

I considered that. But, I wasn't looking at anything related to efficiency. I was simply matching up the kWh used (from since last charge) and the % battery remaining. I actually was getting pretty good efficiency on the drive at 3.5 mi/kWh going 76 mph in 40 degrees. I'm now back to my computer and will try the suggestions above to see what information that gives us. Back in a bit!

 

[Halodde]

@borski @DeaneG @SaratogaLefty
Gents, is this the actual battery capacity information?

"capacityKwHr": 86.26999807171524

So, I have just over 86 kWh at 100% currently?

Also, the page is still open. What is the submit option? Is that something I should do? Will that information help us somehow?

 

[momo3605]

More than likely "capacityKwHr": 86.26999807171524 is showing usable battery not total capacity. So the max is ~88.3. You can see this in the other thread, not 92. So you would have 2kwh of degradation not 6. Out of curiosity, how many miles do you have on your car so far?

It's also possible that this number is not 100% what we think it is and can get swayed by calibration errors.

 

[segbrk]

Also, the page is still open. What is the submit option? Is that something I should do? Will that information help us somehow?

Submit saves the info you see where only @borski and I can read it. This was originally for us to just map out the API and see what all the different values in different cars are, but we may also use this to plot the capacity data vs mileage and other factors, since that’s come up on here a lot lately.

 

[Halodde]

Submit saves the info you see where only @borski and I can read it. This was originally for us to just map out the API and see what all the different values in different cars are, but we may also use this to plot the capacity data vs mileage and other factors, since that’s come up on here a lot lately.

Cool. I submitted it a little while ago since I figured it might help someone.

Did I focus on the right content and interpret the information correctly regarding the current usable capacity?

 

[segbrk]

Did I focus on the right content and interpret the information correctly regarding the current usable capacity?

I honestly don’t know for sure. Maybe we can find a pattern with some plotting.

 

[Halodde]

More than likely "capacityKwHr": 86.26999807171524 is showing usable battery not total capacity. So the max is ~88.3. You can see this in the other thread, not 92. So you would have 2kwh of degradation not 6. Out of curiosity, how many miles do you have on your car so far?

It's also possible that this number is not 100% what we think it is and can get swayed by calibration errors.

Thank you

Almost 25k miles.

Can I ask why you say the initial usable capacity is 88 and not 92? I was told by Lucid it was 92. And/Or can you point me to the correct spot in the other thread you referred to?

 

[Bus Driver]

More than likely "capacityKwHr": 86.26999807171524 is showing usable battery not total capacity. So the max is ~88.3. You can see this in the other thread, not 92. So you would have 2kwh of degradation not 6. Out of curiosity, how many miles do you have on your car so far?

It's also possible that this number is not 100% what we think it is and can get swayed by calibration errors.

I need to bring this up again. One online source lists the Air GT as having a useable battery capacity of 106 kWh, out of a total capacity of 112 kWh. Is this true? I just wish I could remember where I saw that (it was a British based EV enthusiast site), and post it here.

 

[Unmutual]

Here you go: https://www.myevreview.com/tech-specs/lucid/air/grand-touring

And here is another, different one just to be annoying: https://ev-database.org/car/1316/Lucid-Air-Grand-Touring

 

[Lucken]

And here’s Wikipedi’s thoughts on the subject of battery capacity:

 

[Bus Driver]

Here you go: https://www.myevreview.com/tech-specs/lucid/air/grand-touring

And here is another, different one just to be annoying: https://ev-database.org/car/1316/Lucid-Air-Grand-Touring

Well, you’ve certainly succeeded. Annoying, it is indeed. So no one can really say. Not even Lucid.

 

[elin]

I would think the total distance from EPA rating is based off of usable battery, which would suggest the touring has 92kW usable.

 

[segbrk]

First shot at plotting the data we have so far. I don't see a pattern here at all between just odometer / capacity.

 

[Genghis]

First shot at plotting the data we have so far. I don't see a pattern here at all between just odometer / capacity.
View attachment 18099

That one outlier for the GT at 15k miles and 101 kWh is a bit concerning...