LG Chem -LG-E63 cell discussion

Discussion in 'Hyundai Kona Electric' started by electriceddy, Oct 21, 2020.

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  1. For the record my 2019 pack P/N 37501 - K4050, BMS Rom ID 6220, manufacture date Dec 22/18.
    The same manufacture date as the car, they must have rushed it from the battery assembly plant right to the car production assembly line.:eek:
     
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  3. Anaglypta

    Anaglypta Member

    UK
    Not sure that you're going to get anything usefull from comparing ROM I/D's and part numbers. According to the service campaign 960 BMS TSB your ROM I/D belongs to P/N K4051!

    Up to the point where that TSB was released (18 months into production) there were six different BMS part numbers which could have one of thirty different ROM I/D's with a finishing position of one of six new ROM I/D's depending on which part number you have.

    I'll leave you to try and pick the bits out of that!

    John.

    BMSpn.png
     
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  4. Just comparing differences between the recall battery part #'s and the ones that were produced after the issues .
    It seems that the packs with the BMS part #.....4054 and later, combined with the firmware ID of 6980 (and later?) are not prone to the overvoltage problems. This, in conjunction with the production dates, would help answer the question (what changed in late March, 2020)
    Need to have more documented info on voltages etc @ higher SOC levels (ie 80% and above).
     
  5. ericy

    ericy Well-Known Member

    Isn't it the case that when the dealer applies updates (such as the original BMS update, and the recall that is still coming), that the BMS software version would have changed, but the sticker would most likely reflect the version of firmware present when the battery pack left the factory?

    As far as I know, there is no way with Torque or SoulEVSpy to query the current firmware versions of some of these modules.
     
  6. Anaglypta

    Anaglypta Member

    UK
    You'll need the Hyundai diagnostic kit to do that. :)

    John.
     
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  8. navguy12

    navguy12 Active Member

    I topped the car back up to 90% SOC on Saturday and here are shots of the charging profile, showing no pausing at 80% SOC:

    sharon1.PNG

    In the above shot, the charge event started at 1900 and the same level of power (between 7 and 8 kW on this scale) was maintained for the full event.

    sharon2.PNG
     
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  9. ericy

    ericy Well-Known Member

    It is believed that the pausing would only occur after the update for the recall is applied. Nobody in the English speaking world has this update as of yet - there are apparently some in Korea that do have this.
     
  10. navguy12

    navguy12 Active Member

    Agreed.

    The context is to illustrate how BMS ROM ID 6980 functions on a battery dated 18 June 2020.
     
  11. This is my concern that only Kona's manufactured before March 2020 will be blessed with this new BMS "upgrade" that provides slower top end charging without any explanation how battery pack built after this period are different. Are they really different? How? and why did it take Hyundai seven months to acknowledge a presumed production change that does not involve crippling charge speeds and somehow mitigates our cars from blowing up?
    In context to recent reported 3rd quarter profit loss($230 million) related its ICE engines catching fire I suspect I know the answer but nonetheless the silence from Hyundai is not helping its cause.
     
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  13. teamer

    teamer New Member

    Any drone pilot (LiPos but hey, its almost the same) or e-cigarette smoker knows better not to charge/discharge batteries when the cells have more than 0.3v difference ... 1v is way too much!
    Guess i will add this as push notification to my app!
     
  14. The only vaguely plausible explanation I can think of is that later cars are guaranteed to have the 960 update and as we understand it none of those of so-far have experienced an incident. Perhaps those later cars will be updated later on a normal priority basis.
     
  15. Until now, no incident but possibly a pack defect:
    https://insideevsforum.com/community/index.php?threads/stopped-kona-after-lasted-bms-update-we-found-7th-cases.9781/#post-114352
    Still awaiting pertinent info from the pack label
     
  16. Recoil45

    Recoil45 Active Member

    It seems to me there are no differences in the pack. Only a BMS update that protects the cells from overcharge. Existing packs probably have cumulative cell damage.


    Sent from my iPhone using Tapatalk
     
  17. I read a little further on this PDF file, more specifically the 4.6 Safety Specification chart (further down the reference)
    Interesting that the 4.6.3 Overcharge specs dictate "cells charged per 4.1.1 shall be overcharged at 114.5 - W rate until SOC reaches 200% or cell voltage reaches 8.3 V whichever comes first".
    The result " no explode and venting below cell SOC 130 %" which is well above the 2.4 protection limit specification of 4.45 V.
    Also note at the bottom of the chart, how the tests will be done " the cells to be constrained in between 2 bakelite flat plates (290 * 180 * 10 T) and tightened 6 M6 sized bolt and nut with > 10 kgf * cm torque. (no such restraint in the Kona pack) - maybe expansion of the cell pouches?
    The more I read , the more interesting this becomes;) kind of steering to a production fault of the cells themselves - not performing to the overvoltage specs.
     
    Last edited: Nov 23, 2020
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  18. Telek

    Telek New Member

    I don't know if this was pointed out already, but that's NOT what the normal charge limit is. That's from absolute limits, not designed parameters.

    The design usage is 4.2V charge and 4.166V OCV after charge, it's very clear about this and even gives you a table for that.
     
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  19. Not having checked out the E63 cell spec document in EE's first post until today, it seemed obvious to first plot out the LG-specified open-circuit voltage (OCV) v.s. SoC and compare that with data I've collected during the last few months from Torque Pro. I'll first note that voltage while driving is certainly not "open circuit" by definition but when many points are averaged should trend slightly under OCV because in those conditions the battery sees far more discharging than charging and suffers voltage drop due to pack resistance. I'm unaware if OCV can be measured by us while the pack is unloaded; certainty when OBD comms are active to support TP there some battery draw taking place. Trickle charging might offer better data; will look at that another time.

    I should mention that my Kona is about 28 months old now and some deterioration is inevitable, although I don't know how that is reflected in OCV.

    So, the blue line is the LG Chem OCV spec against LG's definition of SoC, while the many thousands of scatter points are cell voltage from my car while driving against Hyundai's definition of SoC, both the displayed and BMS values.

    First note that using SoC displayed or BMS as the X-axis reference doesn't matter much as the black trendlines are closely clustered together at roughly about 0.06 V under the OCV spec. Average driving current X cell resistance could be responsible for part or most of that.

    Second, there is no reason why Hyundai should necessarily have adopted LG Chem's definition of "SoC"; they may have a buffer down at the lower end of the voltage range which will skew the slope, or have other variations.

    I don't have any cell voltage data close to our displayed 0%. If anyone has that please post it.

    OCV spec vs actual dring data.PNG
     
    Last edited: Feb 21, 2021
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  20. Telek

    Telek New Member

    @KiwiME very interesting!

    I'm not familiar with the Kona, but certainly the BMS has the ability to check cell voltages before the contactors are engaged while the car is off and unplugged. With the Bolt, depressing the brake pedal "wakes up" the computers and allows cell voltages to be taken before the HV battery is connected to the car.

    Another thing to keep in mind is the pack temperature.
     
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  21. Yes, you're right because that's what the campaign 196 update does every 1/2 or 1 hour for several hours after charging, while drawing needed power off the 12V battery. The problem is that OBD data is likely unavailable.

    85CEE223-B2D0-4749-8BF5-86D755A23268_1_201_a.jpeg
     
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  22. I notice the link to the Queenbattery PDF no longer works (as provided in the leading post in this thread ... maybe lucky to have stumbled on to it before sh@# hit the fan?o_O). However if one is fortunate enough to have acquired it (or has another source for the file), the specs do mention in the 4.23 OCV table electrical specification of a test temperature of 25 +/- 2 degrees C. Also mentioned are resting times between the charge/discharge cycles as well as "OCV at defined SOC is the average of OCV at the same SOC measured by charge and discharge direction".
    So far your cell voltage chart seems pretty accurate considering the limited test performed;)
    Thanks for the graph and look forward to your further charging results
     
    Last edited: Feb 22, 2021
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  23. eurokeitai

    eurokeitai New Member

    The PDF is still downloadable for me. Interestingly it has cycle life and storage life graphs in the end! Even with worst conditions, the cell appears to last at least ~800 cycles until it has degraded to 80%, which at 400km range translates to 320000km. The storage life graphs are less assuring

    e63_storage.png
    Roughly 1-5% degrading per year, depending of SoC. Unfortunately the colors of graphs have been lost, so it's not clear which SoC was the "1%" degrading line, and which one the "5%" one.
     
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