Battery health

E

Electric Rich

Active Member
Hi, I havent seen this but, just wondering if you can tell if the kona battery is losing its capacity to charge fully.
The charge indicator on the right of the dash has around 18 segments. Thats 5.5% for each segment potentially. If the battery loses say more than 6% of its storage capacity, would we see that charge indicator only showing 17 bars when fully charged?
I think the first Leafs worked that way, not sure if it will apply to the Kona EV series 1?
 
Electric Rich said:
Hi, I havent seen this but, just wondering if you can tell if the kona battery is losing its capacity to charge fully.
The charge indicator on the right of the dash has around 18 segments. Thats 5.5% for each segment potentially. If the battery loses say more than 6% of its storage capacity, would we see that charge indicator only showing 17 bars when fully charged?
I think the first Leafs worked that way, not sure if it will apply to the Kona EV series 1?
Click to expand...
The Leaf actually had 2 separate indicators - Battery charging SOC (inner) and Battery capacity (outer segments 2 red and 10 white - on a good day)
15TDIuslhd_LEAFhelios018.jpg.ximg.l_full_m.smart.jpg

Hyundai only included a charging status SOC indicator which definitely will not reflect degradation;)
Instrument-cluster-2019-Hyundai-Kona-EV-Dashboard-Indicators-10.jpg
 
Although I've never owned one, my understanding is that the Leaf has a separate dash indicator for health starting with 12 bars.

I expect the Kona's SoC percent and bar indicator to always use 0-100% and remain in sync. No one has reported so far that it doesn't and we're seeing a few Konas and Niros heading towards 90% SOH.

EDIT: Ha, EE beat me to it!
 
KiwiME said:
the Leaf has a separate dash indicator for health
Click to expand...
I found when both my Leafs lost one capacity bar the only change was the proportional time reduction to reach 100% SOC bars.(First bar loss ~ 15% and ~7.5% each bar thereafter)
So justifiably given to good reason, I would expect Kona EV SOC indicators to do the same, which should be an exact indication only if previously recorded time to reach a given SOC using the same charge rate.
Better off using an app/dongle if gut feeling tells you that charging is getting quicker to reach that given SOC.
 
Thanks guys, I would like to see all manufacturers have a display that shows battery health as a standard feature.
Won't happen anytime soon though.
 
Since 50,000 kms my SOH has slipped progressively through from 100% to 98% down to 93.5%at 70,000kms. Of course I worry though it's probably normal but, of course, no info is forthcoming from Hyundai. Dealer asks gets generic meaningless answer re warranty.
I've used Car Scanner cos I'm curious, but if I didn't I would be blithely ignorant. Is that better or worse? Dunno.....
 
Hi Guys and Girls'
I work my battery state of health like this ,last 10,000 ks average was 168 watts per km and GOM says range 385 km= 64,640 watts in the battery pack.
so after 66,00o kms i still have 100% state of charge, usually charge at home 7 kw to 100 % Jim
 
I’ve found the dash reading of efficiency is optimistic by about 5% over the actual energy usage, which can be calculated using OBD data.

The amount missing is coincidentally about the same as the energy used by the LDC, meaning all 12V systems.
 
KiwiME said:
I’ve found the dash reading of efficiency is optimistic by about 5% over the actual energy usage, which can be calculated using OBD data.

The amount missing is coincidentally about the same as the energy used by the LDC, meaning all 12V systems.
Click to expand...
That's handy to Know especially as i do,not have a OBD thingy so mine at 176 watts per km and showing 385 km range is 67.9 kwk
that's more than the 64 kwh battery size ????
 
For the record: Nova Scotia 2021 Kona EV, 74000kms. Car Scanner is showing 100% SOH and I'm not sure if I believe it. Maybe I'm just lucky!
I do charge almost always at home, 4.4kw, and aim for 80%, but that can catch you out if you want to travel at short notice, but in general the State-Of-This-Customer-Satisfaction is fairly close to 100.
Does anyone know what State-Of-Health means exactly? Total Capacity compared to New? Charge Energy compared to Discharge Energy?
My car was manufactured after the initial panic about fire risk, so hopefully the QC department were extra vigilant!:-)
 
I think most of us would expect SoH to mean the current capacity as a percentage of the originally-advertised capacity but no one outside of Hyundai could be expected to know exactly how that's calculated in the Kona. To make a better guess a good rabbit hole to start in would be to search for patents filed by Hyundai, Mobis and LG Energy. There are also lots of research papers on the general subject.

We do know that 70% is the point under which the battery warranty applies. So far, in all the forums (including the 1st-gen Niro) I don't recall seeing any reports under 90% so far, however there are many under 95%.

We also can deduce from the tendency for SoH to remain at 100% for some time (4 years on my original 2018 battery) that the initial degradation is either not revealed or compensated for in some way, but it's not proven how they've done that yet.

We do know that when new 100% SoC (displayed) equates to 95% - 97% SoC (BMS), where the latter is defined by LG in the table below for the original E63 cell. It's possible and even likely that this margin is absorbed to cover initial degradation, but so far no one has posted direct evidence that it does.

SoC(BMS), cell OCV
100,4.166
95,4.108
90,4.051
85,3.997
80,3.945
75,3.895
70,3.846
65,3.799
60,3.755
55,3.695
50,3.663
45,3.642
40,3.625
35,3.610
30,3.593
25,3.571
20,3.537
15,3.488
10,3.446
5,3.413
0,3.167
 
The SoH on my Kona was down to 91% in december 2023 when the BMS software was updated. This resetted the SoH to 100%. It is still at 100% 9 months and 25000km later. I don't think the SoH shows the battery degration but some % of BMS out of calibration.
 
After I purchased my 2020, I also purchased an OBD that shows detailed Cell charging for all 98 cells. I seldom charge to 100% (unless I'm taking a long trip), but when I do, I run my OBD diagnostic to see what the SOC of each cell is. Last time I did this, all of the cells were still 4.18 (whatever that value means). I've included a pic ..111123 Charged to 100% after BMS SW update .webp
 
I'm guessing that your figure of 4.18 is the open-circuit-voltage of each cell, indicating it is fully charged. Also the fact that they are all the same is a good indicator of the state-of-health, but as KiwiME said above, nobody here knows exactly how LG or Hyundai define SOH.
When people ask the range (all the time) I tell them 450kms winter, 350kms summer, and my car is still doing that at 4yrs/75000kms.
Trailer/Rain/Cold/Snow all bets are off!
 
Tim94549 said:
... all of the cells were still 4.18 (whatever that value means)...
Click to expand...
The datasheet for the model E63 LG Energy cells used in the early Kona can be found with a search and indicates that LG recommend a maximum voltage of 4.166 OCV. Even though none of us still have those early cells due to the battery recall, I doubt the specifications of the replacements are any different.

Normally 4.20 is the maximum used for a lithium-ion NMC cell, but by limiting it slightly the full-charge cycle lifetime down to a selected SoH can be substantially increased. That's why we get more cycles out of an EV than our smartphones. There is a similar limit at the low end, 3.167 OCV v.s. perhaps 2.5 or 3.0.

Because the digital resolution of the cell (parallel group of 3) measurement is 0.02 I would expect that to appear (over OBD) as a truncated value of 4.16. Having 4.18 probably means that the voltage is between 4.18 and 4.20. But if cell balance is excellent (and it is) you can easily determine the exact average voltage by dividing the total pack voltage by 98.

Pending that information from @BernieNS, perhaps we are seeing evidence that the so-called "upper buffer" is being absorbed to delay the onset of initial SoH loss? If this is the case, it would be the first time I've seen proof of it.

As a side note, I'm now seeing a few reports of Kona SoH values under 90%.

IMG_4496.webp
LG-Chem L63.webp
This graph is my own, derived from the datasheet.
 
KiwiME said:
The datasheet for the model E63 LG Energy cells used in the early Kona can be found with a search and indicates that LG recommend a maximum voltage of 4.166 OCV. Even though none of us still have those early cells due to the battery recall, I doubt the specifications of the replacements are any different.

Normally 4.20 is the maximum used for a lithium-ion NMC cell, but by limiting it slightly the full-charge cycle lifetime down to a selected SoH can be substantially increased. That's why we get more cycles out of an EV than our smartphones. There is a similar limit at the low end, 3.167 OCV v.s. perhaps 2.5 or 3.0.

Because the digital resolution of the cell (parallel group of 3) measurement is 0.02 I would expect that to appear (over OBD) as a truncated value of 4.16. Having 4.18 probably means that the voltage is between 4.18 and 4.20. But if cell balance is excellent (and it is) you can easily determine the exact average voltage by dividing the total pack voltage by 98.

Pending that information from @BernieNS, perhaps we are seeing evidence that the so-called "upper buffer" is being absorbed to delay the onset of initial SoH loss? If this is the case, it would be the first time I've seen proof of it.

As a side note, I'm now seeing a few reports of Kona SoH values under 90%.

View attachment 23351
View attachment 23352
This graph is my own, derived from the datasheet.
Click to expand...

Interesting. Thanks !!
 
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