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I'm playing around with canbus PID values based on JeJuSoul's mappings, mainly to monitor the state of the HV battery. Almost all of the readings that I'm getting look fine except for the Total Charge/Discharge values.

Total Charge = 3644.6kWh, Total Discharge = 3525.4kWh and, at the time of that reading, the BMS SOC was at 60% which, for a 64kWh battery translates to 38.4kWh remaining. Adding all of those together gives an excess charge of 80.8kWh - a 2.3% discrepancy.:unsure: I could sort of understand it if it was the other way, maybe the battery would have been fully charged before connecting to the car electronics but other than some fairly severe leakage I'm at a loss to explain it.

Does anyone else have a similar discrepancy and/or does anyone have a suggestion as to why it might be - or have I got a duff car?
 

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Loses in the battery itself. Similar story in our Soul. I think values we can see are measured on the wires going in and out of battery and it seems not every electron going into battery comes out later.
Maybe someone more technically minded can explain it better
 

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Kia Soul EV 2020
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Or HVAC? Electronics? Battery care? You don't know what is actually included in these figures.

I have seen it somewhere, but find how long the car has been on? That would be interesting...

If you have access to the app, you can get this, just for the last month though:
149387
 

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As said, you will never get the same energy out of any rechargeable battery as that which you put in whilst charging. There are always some internal losses within the cells, interconnects etc. Lithium Ion cells are amongst the best in this respect but there will still always be a little discrepancy due to energy lost as heat. Peter
 

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Or HVAC? Electronics? Battery care? You don't know what is actually included in these figures.

I have seen it somewhere, but find how long the car has been on? That would be interesting...

If you have access to the app, you can get this, just for the last month though:
View attachment 149387
Your screenshot from the UVO app triggered me. Just this morning I looked at the same data and found it very confusing. Just for fun: calculate the average daily distance yourself and see if the 23 km is correct. Also, with 7,75 km/kWh you would expect the GOM to show (64 x 8 =) 512 km of range on average. That would be amazing. The 7,75 km/kWh translates to 12,5 km / kWh which is equally amazing. To top it all off: you and myself seem to be able te recuperate almost a third of our energy use. That is actually impossible. To be clear: your figures are almost similar to mine, this is not a fluke.
 

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......To top it all off: you and myself seem to be able te recuperate almost a third of our energy use. That is actually impossible........
I don’t understand how you work that out? To get 100% recuperation would of course be completely impossible due to multiple various energy losses. 30% is very reasonable in my head at least. I estimate I get around 45% regeneration as I live in a mountainous region. I am almost always ascending and descending. Almost all braking on these cars is done by regeneration. The friction brakes do literally almost nothing. Peter.
 

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Your screenshot from the UVO app triggered me. Just this morning I looked at the same data and found it very confusing. Just for fun: calculate the average daily distance yourself and see if the 23 km is correct. Also, with 7,75 km/kWh you would expect the GOM to show (64 x 8 =) 512 km of range on average. That would be amazing. The 7,75 km/kWh translates to 12,5 km / kWh which is equally amazing. To top it all off: you and myself seem to be able te recuperate almost a third of our energy use. That is actually impossible. To be clear: your figures are almost similar to mine, this is not a fluke.
I think you are confusing a lot of things here.

Anyway, let me start with the known data:
  • I have done about 1300miles or about 2000km;
  • I have also a record of dispensing 228kWh from my home charger. I have also at least 3 rapid charges away from home, but I will say are worth about 80kWh (which is not certain, but I have a record of 67kWh from 2 charges).

If I do the sums, that gives a 4.2mile/kWh. That gives me a GOM of 270miles, which it does in reality.

Now let's look at the screenshot: the total distance is 2064km and energy consumption is 263kWh. That gives the exact figure from the app: 7.7km/kWh, which is 129Wh/km or 12.9kWh/100km. In Imperial units that is 4.8mile/kWh. I have never seen 307 on the GOM.

But you see, I'm talking about charging, while the app gives me a figure of "consumption"! My charging figures include losses in charging, battery, environmental, etc. If one considers the charging losses at ~10%, now my "sure" figures will become very similar to the app figures.
 

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Discussion Starter · #8 ·
As said, you will never get the same energy out of any rechargeable battery as that which you put in whilst charging. There are always some internal losses within the cells, interconnects etc. Lithium Ion cells are amongst the best in this respect but there will still always be a little discrepancy due to energy lost as heat. Peter
OK, thanks, So are we then saying that, in fact, a 2% loss for internal factors is reasonable (ie I don't have a duff car)?
 

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I don’t understand how you work that out? To get 100% recuperation would of course be completely impossible due to multiple various energy losses. 30% is very reasonable in my head at least. I estimate I get around 45% regeneration as I live in a mountainous region. I am almost always ascending and descending. Almost all braking on these cars is done by regeneration. The friction brakes do literally almost nothing. Peter.
I was maybe a bit to strong in my wording, I meant that it seemed impossible. During normal driving air resistance, rolling resistance and mechanical friction require energy, as does accelerating. Regenerative breaking only recuperates kinetic energy so at best you will recuperate the energy spent during acceleration. This Wikipedia page has some interesting graphs which show that during urban driving, about 27% of the energy is spend on acceleration (basically speed-changes). During highway driving that is about 2%. Regenerative breaking has its own efficiency losses and most people drive a combination of highway and urban. But recuperating 30% of total energy on average is near impossible. You live in a mountainous area, I live in the Netherlands and UVO tells my a recuperate 30%.
 

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I think you are confusing a lot of things here.
I am not giving up :)
I still think the screenshot tells me that I got 2064 km out of 263 kWh, which means an average range of 496 km per 64 kWh. That is extremely impressive. I have seen screenshots of dashboards with GOM showing 500 km or more, but those are exceptions, one-time flukes. To be clear: my figures are almost exactly the same (albeit with less total km's) and that involved some trips on the highway. This has nothing to do with charging losses etc, the figures shown are after charging and they tell me what I can expect when I start my drive.
 

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@Multikoe No need to give up, we are all trying to understand things.

Just one more point, using JuJu's interpretation has it's issues, because it is still a guess. Both figures might not have anything to do with consumption. I will try and get my CarScanner app running and see what it says, as I think it has different readouts from JuJu's (I'm not certain here, I just know that JuJu's PID work with Torque app).
 

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Your screenshot from the UVO app triggered me. Just this morning I looked at the same data and found it very confusing. Just for fun: calculate the average daily distance yourself and see if the 23 km is correct. Also, with 7,75 km/kWh you would expect the GOM to show (64 x 8 =) 512 km of range on average. That would be amazing. The 7,75 km/kWh translates to 12,5 km / kWh which is equally amazing. To top it all off: you and myself seem to be able te recuperate almost a third of our energy use. That is actually impossible. To be clear: your figures are almost similar to mine, this is not a fluke.
I don't own one of these cars, so you may discount my suggestion. However...do the consumption figures make sense if they are just reporting the actual propulsion efficiency? The screenshot shows 73% of energy is used for driving, the remainder for climate and other electronic systems. If factored by that value, efficiency figure could then reduce to 5.66 km/kWh, or 3.5 miles/kWh. That seems about right, although it may be that regen is also treated separately.
 

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I don't own one of these cars, so you may discount my suggestion. However...do the consumption figures make sense if they are just reporting the actual propulsion efficiency? The screenshot shows 73% of energy is used for driving, the remainder for climate and other electronic systems. If factored by that value, efficiency figure could then reduce to 5.66 km/kWh, or 3.5 miles/kWh. That seems about right, although it may be that regen is also treated separately.
That could be an explanation, but that would be confusing still. As a driver, I would be mainly concerned about the range I can expect, all things considered. Especially because the GOM is based on the average consumption over the last couple of drives, which must include climate settings, regen settings and other things.
 

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@Multikoe No need to give up, we are all trying to understand things.

Just one more point, using JuJu's interpretation has it's issues, because it is still a guess. Both figures might not have anything to do with consumption. I will try and get my CarScanner app running and see what it says, as I think it has different readouts from JuJu's (I'm not certain here, I just know that JuJu's PID work with Torque app).
I am learning all the time, these discussions actually are a big part of the reason why I enjoy owning an EV...

I like looking at data, I like the fact that the car enables you to get this data. I kept track of my gas consumption for decades and would like to do the same for the Niro. However, the data in the app is simply confusing and I don't trust the figures as they do not align with what I expect. I might be looking at it wrong, but unless someone actually does the math and shows me exactly what the data in the app is showing, I will be confused...
 

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I think you are confusing a lot of things here.
I am confused, that is for sure :)
I sat in the car this morning and wrote down the last 18 entries in the consumption history list that the Kia shows in the EV menu. I then calculated the average consumption total and came to 6,5 km/kWh. Which gives me a range of 417 km. This seems a bit short, but that's not important. What's important that if you simply do the math on the data from the car and then look at the data in the app, one of them is wrong. The data from the app is way to optimistic, or the data in the car is way too pessimistic. It could still be that both datasets are based on different data (charging energy vs. consumption) but that would be very strange.
 

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The data from the app is way to optimistic, or the data in the car is way too pessimistic. It could still be that both datasets are based on different data (charging energy vs. consumption) but that would be very strange.
It may be that the car knows things that the app doesn't, like the internal temperature of the battery. The app might not even have the full driving history information. In that case the app has to use some default average values. I'd trust the car better than the app if they are different.
Also I think 6.5mk/kWh is a realistic value for a Kia e-Niro.
 

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Ok so the track record of the app is pretty bad, to put it mildly. I trust the car to get stuff right, but wouldn’t trust the app when there is any discrepancy such as this. The app developers seem to be complete amateurs at their game IMHO.

I agree the app consumption figure seems ludicrously optimistic. (I also wish it was using miles on this screen too!).

So just consider my app screen for a trip I did yesterday. It shows 9.38 km/kWh which is a whopping and unrealistic 5.83 miles/kWh average for that day. I know it was less as I watch the daily trip report and I never typically achieve that figure for a full back and forth round trip. (I can see very high figures for one way trip going downhill but it’s always clawed back on the return uphill journey, naturally).

I reckon the silly numpties who produced the app have used the kWh consumed value for just the car propulsion energy portion (the purple 84% segment of the energy mix). With the remaining 16% ancillary energy not included in the efficiency calculation.

So lets try this theory out. Take the 4.68kWh indicated consumption and add 16% (to get to the real consumed value) That gives us 5.43kWh consumed. So now divide 44km by 5.43kWh we get a much more realistic 8.1 km/kWh which in old money is 5.03 miles/kWh. That is much more in keeping with what I see in the car trip meter after such journeys in the summer.

Of course it drops severely in the cold winter months. My average shown on the cumulative trip screen for the last 11 months is only 4.0 mile/kWh. It is slowly nudging up in 0.1 steps as we progress through the summertime. I have not reset it since getting the car about 3100 miles ago Last September. I wasted lots and lots of power for quite some time after getting the car (through the winter lockdown) by spending dozens of hours sat in the car, playing with stuff with the heating on. So I think my cumulative figure would have been way better if I had not done that in the autumn/winter last year.

Does this all make any sense?
Peter


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I reckon the silly numpties who produced the app have used the kWh consumed value for just the car propulsion energy portion (the purple 84% segment of the energy mix). With the remaining 16% ancillary energy not included in the efficiency calculation.

Does this all make any sense?
Peter
That makes total sense. As in: it is a logical explanation for a rather dum mistake. I can follow the logic but only from a technical point of view: it might be interesting to know the "real" efficiency of the car as it tells you something about the battery, the drive train, the aerodynamic properties etc. But a regular driver has no use for this information.

Ah, the power of "the internet" continues to amaze me! This was interesting.

Now that you are on a roll, please have a look at the daily km's count.....
 

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Discussion Starter · #20 ·
@Multikoe No need to give up, we are all trying to understand things.

Just one more point, using JuJu's interpretation has it's issues, because it is still a guess. Both figures might not have anything to do with consumption. I will try and get my CarScanner app running and see what it says, as I think it has different readouts from JuJu's (I'm not certain here, I just know that JuJu's PID work with Torque app).
I think that both JeJu and Car Scanner are using the same PID values. When I go into the customization on Car Scanner it uses the same text to list the same options as JeJu. Also, the Total Charge and Total Discharge values I'm getting from JeJu are identical to those in Car Scanner.

In conclusion, I'm pretty confident that the values I'm getting are correct, it is really just a question of whether my car's readings are the norm or outside of the norm.

What readings do others get using Car Scanner?
 
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