Degradation at 37k miles...

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FloridaSun

FloridaSun

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So, I just finished charging to 100% to check my buffer and I lost another 0.5% of the buffer since early July. At 100% SoC Display, I'm now at 97% BMS.
On a new Kona, it's probably between 94.5% to 95.0% SoC BMS at 100% SoC. So, I lost 2 to 2.5% in just over 37k miles/60k km. This would mean about 20% degradation at 370k miles if degradation is linear which it is not. It usually slows down after an initial drop.. Still got 3% buffer remaining before my range will start dropping. 326 mile/522 km range at 100%.
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Maple said:
I am wondering how the torque software knows the actual SOC is 97%.


Sent from my iPhone using Inside EVs
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It just displays what the actual BMS is reporting as SOC. BlueKona, if its helpful to you my BMS reported SOC when my battery was literally brand new was 95% and is currently at 96.5% 10 months and 16,000 km later.
 
apu said:
It just displays what the actual BMS is reporting as SOC. BlueKona, if its helpful to you my BMS reported SOC when my battery was literally brand new was 95% and is currently at 96.5% 10 months and 16,000 km later.
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So, it appears that the rising SoC BMS number is a fairly accurate way to measure degradation..
 
It's not really 20% "degradation", as you noted it's 20% of the margin until degradation starts to affect range. You could consider that Hyundai "warranty" a loss where the battery has under 70% capacity, a fairly extreme degradation. On that basis you have 35% total and you've used 2%, so you could say your degradation is about 6% of that which Hyundai consider acceptable.

As an added note, I do find it interesting that your cell voltage at 100% SoC-disp is still at 4.16 V, the same as it would have been when new. Where is the margin being used up?
 
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KiwiME said:
It's not really 20% "degradation", as you noted it's 20% of the margin until degradation starts to affect range. You could consider that Hyundai "warranty" a loss where the battery has under 70% capacity, a fairly extreme degradation. On that basis you have 35% total and you've used 2%, so you could say your degradation is about 6% of that which Hyundai consider acceptable.
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I don't think bluekona was saying it was 20% degradation rather he was making a linear prediction of what degradation might be at 370,000 miles.
 
KiwiME said:
It's not really 20% "degradation", as you noted it's 20% of the margin until degradation starts to affect range. You could consider that Hyundai "warranty" a loss where the battery has under 70% capacity, a fairly extreme degradation. On that basis you have 35% total and you've used 2%, so you could say your degradation is about 6% of that which Hyundai consider acceptable.

As an added note, I do find it interesting that your cell voltage at 100% SoC-disp is still at 4.16 V, the same as it would have been when new. Where is the margin being used up?
Click to expand...

From my observations on my car pre BMS update Torque Pro reported 94.5% SoC BMS, 100% SoC display. Immediately after the BMS update to my car Torque Pro reports 96.5% SoC BMS, 100% SoC Display.

So I'm guessing that Hyundai "pinched" a little bit of the head room to achive the slightly higher published range figure!

John.
 
apu said:
I don't think bluekona was saying it was 20% degradation rather he was making a linear prediction of what degradation might be at 370,000 miles.
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Ah, didn't spot that...
Anaglypta said:
... 94.5% SoC BMS, 100% SoC display. Immediately after the BMS update to my car Torque Pro reports 96.5% SoC BMS, 100% SoC Display.
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The battery's 'odometers' are reset to zero when the update is applied so the SoC numbers may not be totally reliable until some history is acquired.
 
BlueKonaEV said:
So, I just finished charging to 100% to check my buffer and I lost another 0.5% of the buffer since early July. At 100% SoC Display, I'm now at 97% BMS.
On a new Kona, it's probably between 94.5% to 95.0% SoC BMS at 100% SoC. So, I lost 2 to 2.5% in just over 37k miles/60k km. This would mean about 20% degradation at 370k miles if degradation is linear which it is not. It usually slows down after an initial drop.. Still got 3% buffer remaining before my range will start dropping. 326 mile/522 km range at 100%.
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I like your Torque Pro screens, just got it for my Kona. How can I show every individual cell.
 
electriceddy said:
Just a note, there are 98 cell groups so you will never be able to read individual cells but just the 3 cells in that particular group.
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I am new to Torque Pro, just got it. How do I select & display all 98 cell groups? I have some basic displays working with extra PUD files, but did not see display for each cell group. Thx
 
1st-KonaEV-in-FL said:
I am new to Torque Pro, just got it. How do I select & display all 98 cell groups? I have some basic displays working with extra PUD files, but did not see display for each cell group. Thx
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Try here:
https://insideevsforum.com/communit...verview-and-setup-for-interested-owners.6970/
EDIT: found it (I read this and saved it for when I eventually need it)
https://github.com/JejuSoul/OBD-PIDs-for-HKMC-EVs/blob/master/Hyundai Kona EV & Kia Niro EV/extendedpids/004_Kona&Niro_EV_BMS_cell_data.csv:)
Not sure how to apply it , maybe post the question in the Torque pro installation thread., then I will know as well.
 
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Of note... the BMS can also report the highest and lowest cell voltage, which is far less to have
to read. It also reports *which* cells are the high and low, which in a healthy pack jumps around
because thd cells should be as close as possible. So I only bother reading those 4 numbers.

I haven't seen deltas larger than 0.02V, and the high/low N does change but tends to "stick" in
some places just due to the order in which the BMS internally scans the taps.

_H*
 
Andy Swarbrick said:
Could the "degredation" be anything to do with the Kona actually having a 71kw battery? I wish now I had a reading from day 1.
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Based on the math as also what I've read, the battery is 67 kwh and not 71 kwh. It appears that on a NEW Kona, there is a 5% buffer. 64/100 * 105 = 67.2 kwh. Where did you get the 71 kwh number from?
 
Anaglypta said:
From my observations on my car pre BMS update Torque Pro reported 94.5% SoC BMS, 100% SoC display. Immediately after the BMS update to my car Torque Pro reports 96.5% SoC BMS, 100% SoC Display.

So I'm guessing that Hyundai "pinched" a little bit of the head room to achive the slightly higher published range figure!

John.
Click to expand...
That's interesting.. My SoC BMS stayed the same between before and after the BMS update.. It was 96.5% SoC BMS before and after the update (at 100% SoC Display)
 
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