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Discussion Starter #1
My interest is driver ergonomics, I'm a big fan of head-up displays, and deplore the current trend to ever larger and more distracting console screens. Ralph Nader would turn in his grave...
So this has led to the following Torque Pro additions, they all work for me.

To most EV owners, SoC is just a number for how much the HV battery is charged. In the Kona it isn't even on the main dash display. But it is worthwhile using Torque Pro to examine SoC, because it is central to performance.
Sometimes new owners, trying to make sense of the available range value on the dash (often referred to as the Guess-o-meter or GOM), post something like "The GOM doesn't move down much at first, then it gets a bit faster, then it drops steadily to the bottom". This is actually a clue to how SoC changes, which is different to other numbers.
Labels like km, mile, kWh, have one thing in common - they refer to internationally defined, absolute values. SoC is not one of these, it is a constructed relative value expressed as a percentage, based on a particular volume. So 1% SoC energy for a Kona is not the same as 1% SoC for an Ionic, and as there are always 100% of anything, a SoC % is worth less and less energy as the battery degrades.

Steady driving in ideal conditions, flat running, will produce a constant economy value on the dash, say 12.5kWh/100km (5miles/kWh). If data from this was charted, it would show a flat line for kWh used against km driven. If the same thing is done for SoC%/100km, however, TP data charting will produce a SoC curve, starting fairly flat then gradually arcing upwards. Typical data for this would be a starting value of about 18%SoC/100km, gradually rising over long distances to 21-22%SoC/100km (20%SoC/100km equates to a range of 500km.
The PIDs needed may be like the following:

000_Drive Motor Speed 1,RPM,0x220101,(Signed(BB)*256)+BC,-250,7000,rpm,7E4
000_State of Charge Display,SOC,0x220105,af/2,0,100,%,7E4
005_SoCMaxD @Start,Init_DSoC,,VAL{}+100.0,0,100,%,
005_Trip_Km @Start,Init_km,,VAL{}+0.0,0,500,km,
006_SoC_Used Day,Day_SoC,,VAL{005_SoCMaxD @Start}-VAL{000_State of Charge Display},0,100,%,
006_Speedometer_Check,Speed,,((VAL{000_Drive Motor Speed 1}*60)/7.981))/484.4,0,200,kph,
006_Trip_Distance Trip,Trip/km,,TOT(3600:VAL{006_Speedometer_Check}),0,500,kms,
007_Trip_Distance Day,Day/km,,VAL{006_Trip_Distance Trip}+VAL{005_Trip_Km @Start},0,500,km,
007_SoC_EcoRate Day,SoC_eRate,,TAVG(30:VAL{006_SoC_Used Day}/VAL{007_Trip_Distance Day}*100),10,25,SoC%/100k,

These PIDs suit a day trip, allowing for a stop. Using the TP PID editor or similar, the following need to be set:
005_SoCMaxD @Start needs to be set to current TP SoC, 1 dec. place, at the beginning of the day only.
005_Trip_Km @Start needs to be updated for each Ignition On sequence. If your dash GOM shows miles, run a display for 006_Trip_Distance Trip for km's.

If SoC %/100km charted is on an upward curve while kWh/100km charted is on a flat line, this means that SoC is ever-increasingly being consumed, even for steady running. Conclusions that can be drawn from this are:
As the HV battery empties, the output of kWh becomes less efficient, needing a charge sooner than expected.
In terms of range, halfway is not at 50% SoC, but more like 52-53% SoC.
Possibly this is support for more frequent, 50-80% charges, rather than running the battery right down.

The dash GOM is influenced by the most recent driving, and its range values decline slowly at first, then faster, which sounds like the pattern displayed by SoC usage. Testing confirms this, so the following PIDs are for a TP simulated GOM.
Note that:
[email protected]% needs to be set with the value on the dash GOM from the last 100% charge. This MUST be a km value.
If your range varies widely over the seasons, this PID will need regular updating.
If your TP GOM unexpectedly is incorrect by more than 2-3 km, also reset this PID up or down by about twice the error until correct.
Calculated GOM values change about 2-3km at a time due to SoC values only being available in 0.5% increments, so seesaw around the dash GOM value.

[email protected]%,100%Range,,VAL{}+550,0,600,km,
006_rDivBase,rDivBase,,10000/VAL{[email protected]%},10,25,,
006_Range_Divider,rDiv,,(100-VAL{000_State of Charge Display})/3+23,20,50,,
006_SoC_Ratio,sRatio,,100/(VAL{006_rDivBase}+(100-VAL{000_State of Charge Display})/VAL{006_Range_Divider}),0,10,,
007_Range_to_Empty,GOM,,TAVG(10:VAL{000_State of Charge Display}*VAL{006_SoC_Ratio}),0,600,km,
or
007_Miles_to_Empty,mGOM,,(TAVG(10:VAL{000_State of Charge Display}*VAL{006_SoC_Ratio}))/1.61,0,375,miles,

Finally, if you want some idea of maximum range for your current economy, the following 2 PIDs are alternatives.
Both include trip distance driven, so become increasingly accurate.
eRange adds the GOM calculation, proportional to SoC remaining. Like SoC, it will be optimistic at first, then drop.

[email protected]+GOM,eRange,,(VAL{007_Trip_Distance Day}+VAL{007_Range_to_Empty})/VAL{005_SoCMaxD @Start}*100,0,600,km,
or
[email protected]+GOM,eRange,,((VAL{007_Trip_Distance Day}+VAL{007_Range_to_Empty})/VAL{005_SoCMaxD @Start}*100)/1.61,0,375,miles,

eRange2 adds a value based on average SoC consumption. Typically, in steady running about 95km/60ml/hr, this is about 2.8% SoC/100km above your rDivBase value. The displayed value will be much lower than for eRange, and likely fairly accurate from the beginning.

[email protected]+GOM,eRange2,,VAL{007_Trip_Distance Day}+100/(VAL{006_rDivBase}+2.8)*(1-VAL{006_SoC_Used Day}/100)*100,0,600,km,
or
[email protected]+GOM,eRange2,,(VAL{007_Trip_Distance Day}+100/(VAL{006_rDivBase}+2.8)*(1-VAL{006_SoC_Used Day}/100)*100)/1.61,0,375,miles

The above, of course, is error-free, but if you find any, please let me know..:)
 

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Discussion Starter #3
I've yet to find a chargepoint that serves up "bars" of electricity. After the gen1 Leaf overheating fiasco, there was so much stirring from the owners community that Nissan finally gave in and provided a SoC display, though only as an option. I was one of those owners...
 

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I've yet to find a chargepoint that serves up "bars" of electricity. After the gen1 Leaf overheating fiasco, there was so much stirring from the owners community that Nissan finally gave in and provided a SoC display, though only as an option. I was one of those owners...
Well my home charge point serves me up just over 7 (electric fire) bars of electricity. 🤣 🤣 🤣
Sorry - I'll get my coat.

John.
 
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...If the same thing is done for SoC%/100km, however, TP data charting will produce a SoC curve, starting fairly flat then gradually arcing upwards. Typical data for this would be a starting value of about 18%SoC/100km, gradually rising over long distances to 21-22%SoC/100km ...
I did manually log SoC/GoM and distance over two trips last year and didn't see any particular sign of a curve for the SoC, at least when over 30%. If the SoC relies primarily on CEC and CED, there would be no foundation for a non-linearity. If it has a component of pack voltage included, then perhaps it could be affected.

130162

1. On the July trip I charged 14% at Taupo so that's why the SoC range covered is smaller.
2. Even though it's "summer" and "winter", it was only about 5°C different.
 

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Discussion Starter #7 (Edited)
I'm watching SoC%/100km/km (trip). A couple of data point averages from Ak-Tauranga-Matamata-Ak.
Ak-Tauranga-Matamata 240km, 2425m elevation including the Kaimai range, 100-52% SoC so an average of 20%SoC/100km.
Matamata-Ak 181km, 1250m elevation, 52-13% SoC so an average of 21.5%SoC despite 1200m less elevation.
Plotting SoC against GOM values would be linear as GOM predictions are derived from the SoC curve.
 
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