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Also, I would say that those SOH numbers are not "normal" for a car with 37,000 miles. Whether they are messed up because of past treatment of the battery causing damage or messed up because past treatment screwed up the measurements, it is hard to say without more information. I know for my car, my SOH numbers have behaved as I would expect and I have no reason not to believe they are more or less correct.

To get an idea of your true SOH-C, bring the battery down to true zero and measure how many kWh you put back in as ETS suggested.
For the SOH-R value, I'm not sure of a good way to check this. One thought is to measure you acceleration times and compare that to values published by others. If the battery resistance is high, then you would expect to see reduced current capability and lower acceleration times.

FWIW.
 

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SOH values are calculated based on AmpH.

AmpH is a derivative value, based on average current consumption, which directly depends on the weather, your routes and how heavy is your foot.

It can go both up and down. The only meaningful use of it is to check if your kids were racing too much during the last month - this would drive the AmpH down :)
 

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SOH values are calculated based on AmpH.
If this is true, it could explain why SOH & AmpH values from OBD are often* so unreliable.

The faster you draw power from a battery, the more energy is wasted as heat, so any battery will supply less AmpH (or kWh) when discharged fast, & more kWh when discharged slow**.

Driving so slow that discharge is very slow, available kWh will increase, possibly even higher than the original specs. That would explain readings of "100%" after tens of thousands of miles. However when "kids" like me ;) are racing "too much" :devilish: the higher discharge speeds, will make it read unrealistically low.

So I wonder why OBD wouldn't simply measure the capacity while charging, like we now do. At that time the current flow is relatively stable at either 1.4 or 6.6kW (L1 or L2). While driving it can oscillate from 83kW discharge when floored, to 72kW charge on regen.

*Kiesling's may be more reliable if his driving habits consistently match the EPA test.
**A more knowledgeable member may view this as overly-simplistic, but I believe it is at least valid as an analogy.
 

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Also, I would say that those SOH numbers are not "normal" for a car with 37,000 miles. Whether they are messed up because of past treatment of the battery causing damage or messed up because past treatment screwed up the measurements, it is hard to say without more information. I know for my car, my SOH numbers have behaved as I would expect and I have no reason not to believe they are more or less correct.

To get an idea of your true SOH-C, bring the battery down to true zero and measure how many kWh you put back in as ETS suggested.
For the SOH-R value, I'm not sure of a good way to check this. One thought is to measure you acceleration times and compare that to values published by others. If the battery resistance is high, then you would expect to see reduced current capability and lower acceleration times.

FWIW.
Oke.. Well again thank you for looking in to it and so much response.
For us in the Netherlands is the 500E "new". So we have to learn a lot.
Next week i have 2 day's off and will give my wife my Alfa Romeo so i can goto zero with the 500E.
And when it's on zero i need to get it on the mode where te battery comes in and say's only 12V availeble right?

I can stay driving cirkles in my village. i have every 200-300 meter a chargerpoint here. When it goes to zero and the 12v "mode" can you still push the car when it's nescerry :p?
 

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No need to keep driving around. Once the gauge goes to zero just park and turn on the AC and lights and let it sit until the auxiliaries shut off on their own. That's when you know the battery system is fully empty.
 

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2017 Fiat 500e (Billet Argento), 2015 VW Golf Sportwagen TSI 5MT (Tungsten Silver), 2002 Honda VFR
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Does anyone know if pushing is a option once battery is exhausted? I know Tesla you can’t move the car ones it’s done it has to be forced onto a flatbed. I’ve seen them get towed with wheels dragging onto the flatbed.
 

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Auxiliaries do not shut off when the HV battery is empty - they keep running. Instead, have a multimeter and measure the voltage at 12 V battery terminals.

Once the DC-DC converter shuts off (meaning, flat HV battery), the voltage drops below 14 V (to 12.8 V or anything that you have in your 12 V).

The time between 0 % on the dash to DC-DC shutoff is about 2.5 hours (with defroster, fan and all the possible lights on).

@twinturboz it seems it is an option. When I released the brake on empty HV, the car started rolling downhill, although the "D" or "R" was on. Once it's flat, the wheels are apparently released.
 

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when it's on zero i need to get it on the mode where the battery comes in and say's only 12V availeble right?
Yes, you need to take the HV battery to 0.00% on OBD, which is reportedly when the motor will no longer propel the car, slightly before the DC-DC cutoff when the 12V battery will suddenly drop from 14.xx v to 12.xx volts on OBD or multimeter. Without either of the latter, you'd have to wait for the 12V batt to drop all the way to 10V for it to activate the warning on the speedo display.

Auxiliaries do not shut off when the HV battery is empty - they keep running.
Reportedly, A/C doesn't actually work after the car's gauge hits 0%, & neither does heat, but the lower-power vent fan works, and rear/mirror defog, low-beams-with-fogs, dome light, hazards, hatch light (& windows & wipers, but I don't recommend those!). Still, as reported above, it can take over 2 hours to go from 0% on the gauge to the required 0.00% on OBD, so driving around a LEVEL PARKING LOT would work, or better yet a sloped one with a charger at the low end.

Alternatively you could get the free AlfaOBD "demo" app & a $19 eBay dongle.

Then you can drive past 0% on the car's gauge, drive around a charger's parking lot until it's near 0.00% on OBD, stop, turn everything that works on, & then plug in after OBD hits 12.xxV.
 

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Does anyone know if pushing is a option once battery is exhausted?
If the transmission ends up in Park, the parking pawl will be set and you won't be able to push the car. See the section "Manual Park Release" in the manual for instructions how to release it — requires getting under the car with a wrench.
 

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From what I could remember my AC and fan shut off about an hour after the gauge went to zero. It still showed about 2-3 Ah remaining at that point.
 

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So it seems like auxiliaries shut down incrementally as the drive battery discharges past 0% on the gauge, taking longer to reach the required 0.00% on OBD. This would tempt me to keep driving until reaching the latter, HOWEVER...:

If the transmission ends up in Park, the parking pawl will be set and you won't be able to push the car.
THANK YOU!!

If you try to save time by driving ALL the way to 0.00% OBD, at your own risk, once you approach that, you can unlatch your seat belt to deactivate auto-park.
 

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If the transmission ends up in Park, the parking pawl will be set and you won't be able to push the car. See the section "Manual Park Release" in the manual for instructions how to release it — requires getting under the car with a wrench.
I can confirm otherwise. I was discharging the car past DC-DC with the handbrake on and transmission in P. Then I pressed D, released the handbrake and the car started rolling.

Maybe the pawl has a 12 V actuator then?
 

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Okay, so you went all the way to the 12V warning. Did you then use a metered charger to check the total input kW?

Either way, please let us know if it did in fact correct the sudden drop "from 18% to 0 % in just seconds" that you reported in post #33 above.
 

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Okay, so you went all the way to the 12V warning. Did you then use a metered charger to check the total input kW?

Either way, please let us know if it did in fact correct the sudden drop "from 18% to 0 % in just seconds" that you reported in post #33 above.
I was standing next to a public charger in my street. And i could not meter the total input. I will see it on my bill next month! They have a slow backoffice at this company. Others you see it right away in your app. But i have to do with it :p.

Comming back on the previous time. When I only went to 0% and not to the 12v warning. It charged 17.5KWh that time. So i am curious about the diffference this time!

I want to thank you for al your time and tips and tricks! For us this is a "new" car inThe Netherlands :)
 

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No problem. We're here to help :)

Thanks for the idea about checking total kW input from an app, even if there's no meter on the charger. For example, there's no meter on my local Volta chargers, but their app may show it.

I don't think you can go by an OBD app, since it wouldn't include the EVSE's own power used. The 25kWh EPA spec that we're comparing to is the user's home utility meter reading. OH, WAIT! Now I wonder if metered chargers show their input, or their output! We need input, to compare to EPA's 25kWh input spec.

The difference in total kWh to charge (& your gain in range) should be proportional to what was required to get it from 0% on the gauge to the 12V warning. So I'm curious what you did for that.
 

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Thought I'd note what is (at least for me) a new data point on this. I've definitely gotten the rapid drops at times - typically under a combination of cold temps and sustained high load (freeway or long uphill). Was driving up into the mountains the other day at temps just above freezing, when within 2 minutes gauge went from 52% to 19%, fortunately at end (high point) of drive. Skied for a few hours and upon return to the car, temp still near freezing, gauge read 37%! On downhill recharge got me back to 46% at one point, and return home was normal as expected. I don't think I've seen this kind of change with the car turned off before, anyone else? I tried the 0% recal once, but don't think I succeeded, so that may be at play...
 

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Thought I'd note what is (at least for me) a new data point on this. I've definitely gotten the rapid drops at times - typically under a combination of cold temps and sustained high load (freeway or long uphill). Was driving up into the mountains the other day at temps just above freezing, when within 2 minutes gauge went from 52% to 19%, fortunately at end (high point) of drive. Skied for a few hours and upon return to the car, temp still near freezing, gauge read 37%! On downhill recharge got me back to 46% at one point, and return home was normal as expected. I don't think I've seen this kind of change with the car turned off before, anyone else? I tried the 0% recal once, but don't think I succeeded, so that may be at play...
The more experience I get with this car, the more sure I am that the SOC percentage algorithm is based on predicted total AmpH. That thing is dynamic, and both the sustained load and temperature do influence it.

This winter I'll try to experiment with a ski hill as well - 28 km and 1100 meter elevation.
 
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