Charging loss %

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FloridaSun

FloridaSun

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What is the normal loss from the EVSE to the car?
Last night, I charged from 30 to 80% and the EVSE showed 35.5 kwh delivered to the car.
This means 50% of charge for 35.5 kwh, which would be 71 kwh for 100%. If the loss was 10%, it would be 64 kwh but is the charging loss only 10% or is it more? Trying to figure out if I have any battery degradation yet after 17500 miles.
 
I couldn't find Kona specific references but according the linked article depending on temperature and amount charged Level 2 efficiency is around 89.4% and Level 1 is around 84%. If you charge less than 4Kwh it was worse Level 2- 87% and 74% at level 1. Efficiency gains of Level 2 charging also increased under low (< 50°F) and high (> 70°F) temperatures.
https://ieeexplore.ieee.org/document/7046253
 
Even if there was degradation I doubt that you will see any evidence( well without looking much closer) of it for quite some time. According to torque pro it looks like there is around 3 kw of headroom and around 0.5 to 1 kw on the bottom end. So what this means that once the battery degrades the BMS will start using the extra space as usable battery and continue to report on the car's display that you have full capacity. As you start using more headspace it will be much more critical not to charge to an indicated 100% as that will truly accelerate degradation even further. You would need an app like torque pro to compare the actual BMS SOC report vs what is displayed on the car's screen.
 
apu said:
I couldn't find Kona specific references but according the linked article depending on temperature and amount charged Level 2 efficiency is around 89.4% and Level 1 is around 84%. If you charge less than 4Kwh it was worse Level 2- 87% and 74% at level 1. Efficiency gains of Level 2 charging also increased under low (< 50°F) and high (> 70°F) temperatures.
https://ieeexplore.ieee.org/document/7046253
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Based on 10.6 percent loss, I still seem to get full 64kw..but who knows..
 
apu said:
Even if there was degradation I doubt that you will see any evidence( well without looking much closer) of it for quite some time. According to torque pro it looks like there is around 3 kw of headroom and around 0.5 to 1 kw on the bottom end. So what this means that once the battery degrades the BMS will start using the extra space as usable battery and continue to report on the car's display that you have full capacity. As you start using more headspace it will be much more critical not to charge to an indicated 100% as that will truly accelerate degradation even further. You would need an app like torque pro to compare the actual BMS SOC report vs what is displayed on the car's screen.
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Do we know this as a matter of fact that the car will use up the buffer of extra 3% once the battery degrades or is this a guess?
 
Bluekona pick up cheap bluetooth dongle and an app that can read actual BMS SOC, charge your car up to 100% as indicated on the car display. At 100% displayed the actual BMS SOC on a new battery reads 95%, if you get anything higher you have degradation. Yes the BMS will also steal from the lower end of the battery but it will be much less obvious than on the larger top end buffer.
 
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apu said:
Bluekona pick up cheap bluetooth dongle and an app that can read actual BMS SOC, charge your car up to 100% as indicated on the car display. At 100% displayed the actual BMS SOC on a new battery reads 95%, if you get anything higher you have degradation. Yes the BMS will also steal from the lower end of the battery but it will be much more obvious on the larger top end buffer.
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Will get one.. Any recommendations?
 
BlueKonaEV said:
Will get one.. Any recommendations?
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This is the one I use with torque pro https://www.amazon.com/Panlong-Bluetooth-Diagnostic-Scanner-Android/dp/B00PJPHEBO/ref=sr_1_5?keywords=Panlong+OBD2+OBDII+Bluetooth+Scanner+ELM327+Check+Engine+Light+(MIL)+Car+Diagnostic+Code+Reader+for+Android&qid=1577639803&sr=8-5 Its cheap works well with the free torque lite app or the paid torque pro app. It seems to have some issue with other apps like EV notify, Soul EV spy lite but those are less useful to me so whatever.
 
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apu said:
We do. You can google the information yourself but here is a reasonable article to start you off. https://cleantechnica.com/2018/08/26/the-secret-life-of-an-ev-battery/
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Great article. Based on my use, I should get plenty of life out of my battery. In 17500 miles, I never even made it to low battery warning. 9% was the lowest SoC I have ever had.. On average, i stay between 50 and 80%. On longer trips, I get down to 20 to 25% before I fast charge. I charge about twice a month to 100%, otherwise 80%
 
BlueKonaEV said:
Great article. Based on my use, I should get plenty of life out of my battery. In 17500 miles, I never even made it to low battery warning. 9% was the lowest SoC I have ever had.. On average, i stay between 50 and 80%. On longer trips, I get down to 20 to 25% before I fast charge. I charge about twice a month to 100%, otherwise 80%
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Yes, I suspect if we maintain good temperature and battery charging hygiene out biggest concern will be just batteries dying of old age.
 
apu said:
This is the one I use with torque pro https://www.amazon.com/Panlong-Bluetooth-Diagnostic-Scanner-Android/dp/B00PJPHEBO/ref=sr_1_5?keywords=Panlong+OBD2+OBDII+Bluetooth+Scanner+ELM327+Check+Engine+Light+(MIL)+Car+Diagnostic+Code+Reader+for+Android&qid=1577639803&sr=8-5 Its cheap works well with the free torque lite app or the paid torque pro app. It seems to have some issue with other apps like EV notify, Soul EV spy lite but those are less useful to me so whatever.
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Ordered that one! Thx
 
BlueKonaEV said:
Great article. Based on my use, I should get plenty of life out of my battery. In 17500 miles, I never even made it to low battery warning. 9% was the lowest SoC I have ever had.. On average, i stay between 50 and 80%. On longer trips, I get down to 20 to 25% before I fast charge. I charge about twice a month to 100%, otherwise 80%
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Th lowest I have been is 30%. The most challenging for me is when I go into the city for work. 150 miles each way. I generally want to charge when I get there, but am mostly limited to DCFC. The most recent trip I charged back to 80 when i got there since the batteries were warmer. In the summer I will charge 1st thing in morning when temps are cooler.

My favorite DCFC is the free 50kw one, but that gets busy, and it works best 1st thing in the morning, as I can get in without waiting.
 
BlueKonaEV said:
What is the normal loss from the EVSE to the car?
Last night, I charged from 30 to 80% and the EVSE showed 35.5 kwh delivered to the car.
This means 50% of charge for 35.5 kwh, which would be 71 kwh for 100%. If the loss was 10%, it would be 64 kwh but is the charging loss only 10% or is it more? Trying to figure out if I have any battery degradation yet after 17500 miles.
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OBC losses vary based on the power level. At best it's 91% according to the Hyundai docs. It will be worse at currents lower than 32 amps.
Battery efficiency is around 96% under good conditions according to my own measurements.
But measuring charging energy is not a good way to determine SoH. Charged to 100% obviously you should be able to extract 64kWh by draining it to 0%, then you have the advertised rating.
One way to do that is to record the change in CED minus the change in CEC (in Torque Pro) driving from 100% to zero. These values are how the car determines SoC and I believe they are quite accurate but only read to 0.1 kWh resolution. So your result may be accurate to about +/- 0.4 kWh.
Alternatively there is an unproven SoH reading in Torque Pro, but apparently you need to charge from under 20% to 100% to make it valid. I haven't tried that myself.
 
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I would readily believe that the OBC dissipates about 700 watts when
charging at 7.2-ish kW, just from feeling it and all the other stuff on
the same cooling loop after a couple of hours.

And I did do the all-the-way-to-dead test, finding about 750 additional
Wh after the displayed SOC landed firmly on 0. Wrote it up and all.

_H*
 
apu said:
This is the one I use with torque pro https://www.amazon.com/Panlong-Bluetooth-Diagnostic-Scanner-Android/dp/B00PJPHEBO/ref=sr_1_5?keywords=Panlong+OBD2+OBDII+Bluetooth+Scanner+ELM327+Check+Engine+Light+(MIL)+Car+Diagnostic+Code+Reader+for+Android&qid=1577639803&sr=8-5 Its cheap works well with the free torque lite app or the paid torque pro app. It seems to have some issue with other apps like EV notify, Soul EV spy lite but those are less useful to me so whatever.
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Trying it right now. Torque lite seems to have no ev related information.. maybe i just have to figure out how to use it..
 
BlueKonaEV said:
Trying it right now. Torque lite seems to have no ev related information.. maybe i just have to figure out how to use it..
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I switched to SoulEVSpy as it has lots of EV info there. Torque is too generic - while you can tease out the EV info, it requires lots of fiddling to get it set up correctly
 
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ericy said:
I switched to SoulEVSpy as it has lots of EV info there. Torque is too generic - while you can tease out the EV info, it requires lots of fiddling to get it set up correctly
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Just curious, do these apps display error codes when encountered ?
 
TP is supposed to but I've never used that function. You would have to set that up to tell you in any case.

I tried SoulEVSpy Lite with my generic translucent blue dongle and did get plausible numbers. It does look useful for monitoring in realtime and is certainly far easier to configure than TP. But unless the pay version has logging I'll still have that use for TP in addition to its excellent dash customisation options.
I'll need to buy the recommended dongle for SoulEVSpy because mine kept disconnecting.
 
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