Charging slows down after the recall (BMS update)

[Sean Kim]

Not a few consumers of Kona EV complain that their charging speed has slowed down a lot since the recall.
When the complaint was filed, Hyundai Motor explained why the charging speed of the Kona EV slowed down through customer guidance.
"We added logic to inspect batteries for 80% of charging for this recall," a Hyundai Motor official said. "There is 10-minute battery inspection when charging is not carried out." If the test results confirm that it is normal, the charging process resumes at its original speed, he explained.
With the introduction of battery inspection logic technology through recall, it is expected that users of Kona EV after the recall will not be able to charge their batteries as fast as they did before the BMS update.
https://zdnet.co.kr/view/?no=20201020171657

 

[Orchardman]

Thanks Sean.

Well that's confusing!

So, my take on this is that charging remains at normal speeds until 80% SOC is reached, whence it does a 10-min check, following which if all is normal it continues at the previously normal speed. By "normal" I mean the normal stepped profile on 50 or 100+ kW chargers. Now, what about at 7kW or granny charging - I assume no change at all?

Anyone got any better info?

 

[KiwiME]

It's certainly unclear if the 10 min break appears in AC charging as well but I would have to imagine it does since many of the incidents seemed to involve that mode.

 

[Andy Swarbrick]

Whereas I think the charging speed below 80% is better. Personally I don't charge rapid above 80% so care less about that, whereas I do charge below 80%and care a lot about that.

 

[mikeselectricstuff]

Slower charging on some rapids is also a symptom of the update not being correctly done. If you still have "Aux Battery Saver +" in the dash menu, it's not been done correctly and needs to be sorted.

 

[TonioRoffo]

Absolutely agree - check if Aux Battery Saver+ is still there. If it is, and you charge slower then before, then you are having the problem I had, meaning you have a cell voltage which isn't matching, possibly a fire hazard. Ask them for a correct update (the result may be that your car won't start and they have to check the battery)

 

[GeorgeS]

Well, this is the first information I have heard of what the fix will be on the recall. After 80%, the charging has to slow down because the batteries will not accept full speed at this SOC. This is not because of Hyundai but a limit of the battery chemistry.

 

[electriceddy]

DC charging will slow as per the charging curve as normal, what is not clear is if the pause (to check the cell voltage differentials etc) will also be applicable to A/C charging at that same 80% level, and possibly 90% as well as KiwiME pointed out above.
The cell chemistry definitely has its specifications:
https://insideevsforum.com/community/index.php?threads/lg-chem-lg-e63-cell-discussion.9783/
My guess is the main goal of the new update to improve communication between the BMS and the packs firmware to help alleviate by detection the issues of overvoltage variances between the cell groups.