Dead Kona EV!

In theory the BMS software update improves the situation. Personally I regret having allowed them to perform this upgrade, but that's for an entirely different reason...

 

Gradual degradation, it just got to the point I had to do something. Roadside assist was called out a few weeks ago when I first couldn't start the car after vacuuming and they tested the battery and said it was ok and refused to change it (I made the mistake of charging it prior), I had to laugh, so it happened again and this time so I left it flat at 7.7 volts. It was declared faulty and changed 2nd time around. I've covered 39000 km in 15 months, I don't drive short distances. I think in my case it's just a case of faulty battery, but I hope this can be a life of car replacement, and if I can help others considering the idea, I'm happy to share my journey.

 

Yeah, the loss of aux+ batt saver option was weird. The fact that I've seen my Hyundai logo led light up from time to time but still having issues with a flat 12v battery seems to indicate it is checked at a timed intervals, not continuously monitored for state of low voltage.

 

You're going to cook that LFP into either a useless lump of mixed noble metals or a
firestarter, because the Kona's DC/DC assumes that lead-acid chemistry is attached
and is much less sensitive about overcharge at sustained high float voltages.

_H*

 

I appreciate that nothing is without risk, but this battery is a lithium iron phosphate not lithium ion. The charge characteristics are almost identical to lead acid.
The battery also has a BMS.
The battery is of course lighter and has a better round trip efficiency. It's rated to 60⁰C and I will be taking some temperature measurements soon as we are coming into summer, however the first nder bonnet temps are really cool so I'm not expecting huge temps.
I'm really enjoying the built in volt /capacity gauge which shows 13.2V and 100% each morning when I check it, and there's an on/off/reset switch on the battery as well, so if.you are inclined, you could disable the car with that so it can't be started even with the key (simulated no battery installed).

 

I know, your LFP has a native nominal voltage of 13.2 but in a system that usually floats the bus
at 14.8 or so it's still going to risk an overcnarge situation. The people at Battleborn agree with me.

Let us know how it goes long-term.

_H*

 

Yep for sure.

From my limited investigations so far, the voltage at the LVDC battery terminals does rise to the mid 14s when the vehicle is first turned on, placed into utility mode or charged via an AC charger (I presume also on a dc fast charge). The voltage quickly drops to 13.2, presumably because even overnight the voltage of the LVDC battery is still 13.2v prior to activating or connecting anything.

I'll do some proper logging starting in another week or so.

 

Hi All,

I have a 2021 Kona Electric with about 600 miles on it now. I have had the 12v battery go flat twice.
Electric cars aren't new to me and I do have another one which I have had for about 4 years and never had a 12 v battery issue.

I did some further testing and think I may have found out the reason for the 12v battery drain.
The first time it went flat was 4 days when I was out of town and it didn't get driven, I had left the car plugged in but upon my return it would not start. A jump with another 12v battery resolved the issue.

The 2nd time was after just leaving the car 2 days without driving it this time it was not plugged in. I started doing some testing and I think it might be related to the remote start with climate control.
When I do a remote start with climate control (turning on all heating options, I use the preset Winter option), it is usually super early in the morning, around 4:30am and I'm in the car by 4:45am and away. However a couple of time I have set the remote start, and then had to not go anywhere, so I did a remote stop of the car and got the confirmation that climate had turned off.

The other day I did a remote start in the morning, ended up not driving and then that night I noticed that windows had fogged up, expect for a couple of small patches on the front window. Upon investigating and doing further tests it appears that when Remote Start Climate Control Stops on its own, or you send the Stop command it doesn't seem to truly turn off.

Below you will the spots on my windshield, along with what the vehicle status is via the BlueLink App.

You will notice that while climate control has turned off (yellow light is also no longer on at the front of the car) the Front Defrost is still on. I suspect this is draining the 12v battery. The car appears silent, the fan isn't running and there are no lights on inside the car.

The 2nd image shows the area where the Front Defrost appears to be on.

Unlocking and starting the car and turning it off again seems to turn off the Front Defrost.

I have not had a chance to call the dealer yet, but will do that next week.

Just wanted to mention this here incase this could be the cause???
Would be great if some others could test this theory out.

Thanks

 

I was hopeful that the first of the battery management system code updates done at dealerships would fix the dead 12V problem, but I went camping soon after getting that update done, and was disappointed. The camping trip ended with an unresponsive car that would not recognize the key, which was puzzling until a Prius Prime owner I was chatting with volunteered his idea. "No matter what the problem is, start by charging the 12 V battery." Sure enough, he gave us a jump and then all was well.

Soon after I got a tiny bluetooth voltmeter that velcros to the 12V battery and reads out voltages to your mobile. It's not perfect, but it gives you some insight into what the batteries are doing when you aren't paying attention.

3 screenshots from the battery monitor app follow. But I should say, these are the most regular and normal days, with no driving and no charging. When I drive the car, charge the traction battery, run the climate controls, or if the day of the week contains the letter r, things get weirder. I'll let you know if I figure it out!

 

I've had a chronic dead 12v problem, meticulously documented with graphs and even videos, but Hyundai couldn't care less.

Each battery related service campaign changes the behavior. I haven't seen the problem since the latest, exploding battery recall. Maybe they fixed the 12v problem. More likely they changed algorithms enough that the circumstances that kill my battery just happen to arise less often or not at all.

I bought a compact jump starter the first time it happened, and consider its use a normal occasional part of owning this vehicle. #HyundaiBetaTester

 

In case this might be helpful to others:

My 2019 Kona EV used to fairly regularly end up with a discharged 12V battery, every week or two, even though it was driven more-or-less daily. The symptoms seemed similar to what others report in this thread.

After physically removing the BlueLink and Sirius XM radio modules (thanks to hobbit's instructions at http://techno-fandom.org/~hobbit/cars/ev/offnet.html) I haven't had a single instance of the 12V battery being dead for about two months.

 

Bluelink and XM are draining the 12V ? I've had weekly aux.battery alert in the hyundai emblem.I have yet to be unable to start it,but with winter,and plans to visit sub zero zones,I am glad I have jumper cables at least. What I have noticed, about a 10km/6mile range drop overnight.Parked in a semi heated environment.
@Toolworker

 

If you (or someone else) ping the car via Bluelink, the car's systems wake up and take a few minutes to go back to sleep. This drains about 1% of the 12v battery's capacity.

If the 12v charging algorithm fails to periodically charge the 12v battery, after about 100 Bluelink pings it'll be dead.

 

Bluelink remote start is useless. I won't trust it to unlock/lock the Kona.Last winter I turned it on to precondition. It said "on," but the car was covered in ice without an heat in the cabin. Canada has an issue where Bluelink turns off after 10 minutes which is useless, USA apparently doesn't have this problem. When I bought the Kona EV, I thought Hyundai's first large battery BEV would be better than this. With the battery defect,they would appreciate its early adopters by offering options to a LG battery replacement that is a year,or later for many owners. I will never buy another Hyundai at this point.

 

You do not have a faulty battery. Unless I'm on my 4th faulty battery. The 12V charging logic is faulty. 12V battery charging is a well-known quantity. Some software or hardware logic error is responsible. Let's hope it's software. Just had 356V battery replaced and am up to latest software. Techs seemed to think this will solve 12V battery problems.

 

I recommend buying a portable jump starter.

 

OK. The verdict seems to be in. Months since 356V battery has been replaced and the LogoLight behavior and charging of the 12V battery is like night and day. Three years of improvement on the system has made a difference. The LogoLight is on much more frequently and messing with the charge cable or opening/closing doors does not cancel the 12V charging. My Kona is a work vehicle and having the doors open all day has not killed the 12V. Sometimes I'll look over aa the car during the day and there's that beautiful LogoLight keeping the 12V chock-a-block.

I'm still keeping my Milwaukee M18 adapter in the glove box as a backup, though.

I parked the Kona with new battery at the airport for 12 days and zero range reduction.