Why there are 2 numbers SOC and SOC on display

Rt1AWD

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And they have close but different values usually. What does that mean?
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SpaceEVDriver

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Do you mean as seen by CarScanner connected to an OBD2 device?

Ford protects the battery by keeping a certain percent unavailable to the user through software. When the battery is charged to 100% according to the display, it's still somewhat below 100% of the full capacity. Both values (SOC and SOC Display) are visible to OBD2 scan software such as CarScanner.
 

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Do you mean as seen by CarScanner connected to an OBD2 device?

Ford protects the battery by keeping a certain percent unavailable to the user through software. When the battery is charged to 100% according to the display, it's still somewhat below 100% of the full capacity. Both values (SOC and SOC Display) are visible to OBD2 scan software such as CarScanner.
Exactly. There's "percent of what you're allowed to use" and the "percent of actual capacity of the battery".
EDIT:
Also, just like in gas cars "0" isn't quite "empty"; you can still drive a few miles at reduced power even when it shows 0 miles/percent left
 

HuntingPudel

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The battery has buffers at the top and the bottom to prevent zero actual charge or 100% actual charge (both of those extremes are bad for battery longevity). So at zero SoCD, you will have somewhere around 4-5% actual charge and 100% SoCD you will have somewhere around 95-96% actual charge. Somewhere in the 50% range the two charge levels intersect. ??
 
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Rt1AWD

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Charged the car to 100%. The energy to empty shows 90.8 (0.2 less then max), but SOH shows 98.5. Question: how with degradation of 1.5% it is only 0.2 kwHr less then max
 


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Charged the car to 100%. The energy to empty shows 90.8 (0.2 less then max), but SOH shows 98.5. Question: how with degradation of 1.5% it is only 0.2 kwHr less then max
Because of the bottom buffer, the kWh to empty will never go all the way to zero. When the car stops moving it will still show about 1-2 kWh to empty. So you're down to about 89 kWh usable.
 

SpaceEVDriver

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And also, the battery isn't a volume container; it's a chemical potential energy laboratory, so it can have more than 91 kWh at 100% displayed even when its state of health is lower than 100%.
 
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Rt1AWD

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I also noticed that two temperature sensors on car scanner always show pretty more or less accurate temperature, while the one on the central screen always shows much higher temperature when the car was heated up by the son. Why aren't the accurate measurements displayed on the central screen?
 

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And also, the battery isn't a volume container; it's a chemical potential energy laboratory, so it can have more than 91 kWh at 100% displayed even when its state of health is lower than 100%.
This^^

It’s a mixture of “best guesses,” estimates, and impossible to measure.

It’s not an exact science and the equipment used to measure isn’t exact either.

Plus things like battery temp and external temp also change things.
 

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And also, the battery isn't a volume container; it's a chemical potential energy laboratory, so it can have more than 91 kWh at 100% displayed even when its state of health is lower than 100%.
You’re correct but I find it easier to consider the Battery percentage as an equivalent to a “fuel gauge”. I try not to let it stop below a “quarter tank”, just like I used to do with ICE. I don’t want to be bothered with edge cases and deep details ?
 

SpaceEVDriver

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You’re correct but I find it easier to consider the Battery percentage as an equivalent to a “fuel gauge”. I try not to let it stop below a “quarter tank”, just like I used to do with ICE. I don’t want to be bothered with edge cases and deep details ?
Oh, absolutely. I will sometimes push it into the low teens if I'm heading home, but otherwise I don't like to go below about 20%.

But we keep seeing the question based on the analogy of a battery being a fuel tank and people being confused by the fact that 100% is not 100% is not 100% if the temperatures, discharge rates, etc., are different...
 

Jimrpa

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Oh, absolutely. I will sometimes push it into the low teens if I'm heading home, but otherwise I don't like to go below about 20%.

But we keep seeing the question based on the analogy of a battery being a fuel tank and people being confused by the fact that 100% is not 100% is not 100% if the temperatures, discharge rates, etc., are different...
Yes, and I think it’s fantastic that people take the time to understand the way things work and why they work the way they do. People just shouldn’t try to chase numbers (I’m reminded of that other thread where the company is selling a device that displays all the raw car telemetry ?)
 

SpaceEVDriver

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Yes, and I think it’s fantastic that people take the time to understand the way things work and why they work the way they do. People just shouldn’t try to chase numbers (I’m reminded of that other thread where the company is selling a device that displays all the raw car telemetry ?)
Yes, 100%.

Just drive the car.

I'm going on a 2,000+ mile trip soon, probably a month or so. I'll probably plug in the OBD2 adapter and monitor the car for the entire trip there and again on the way back, but I'm a data nerd (like that's literally one of my official work titles--slightly more prestigious than that, but whatever, it means data nerd).
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