12v battery replacement

Dag Lindquist

Dag Lindquist

Member
Have had my 2019 Kona for 3 years and the 12v battery has started dying regularly. First time was a few months ago so I bought a Li-ion jump starter and actually got a couple more months with no issues. Not so of late so after after searching various forums and some measuring I bought a Group 26R Die Hard battery from Advance Auto ($110). It's a perfect identical fit. No mods required.
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So twice in two days my 12volt battery died after driving it around both days. I purchased a new 26r battery from my Canadian tire it fit great.

So I want to understand this charging method. On an ice car the battery stays charged from an alternator so as you drive and stop basically the voltage is around 12 to 14 volts . Ice cars of course uses the battery to run all functions.

So now the Kona and pls let me know if this is correct. The 12 volt battery is used mainly to start the car and while running the rest of the electrical equipment runs on the main battery . Ok. Does it get an type of charge while running like an ice car. I then understand when the 12v battery gets low it is some how charged up from the main battery. If so that's why the 12v battery never lasts to long, batteries are at there best when the voltage is at the right amount through constant charging Am I correct in my explanation above. Thanks Peter
 
GPM432 said:
while running the rest of the electrical equipment runs on the main battery
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Heat pump, resistive PTC heater, air conditioner, inverter , on board charger, and HV battery heater (via the HV junction box) is directly supplied by the traction battery pack, all other electronics are supplied from the 12V system.

GPM432 said:
The 12 volt battery is used mainly to start the car
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Starting the car initiates the HV battery contactor to close using the 12V system putting the car into "run" mode. When in run mode the voltage applied to the 12V battery is ~ 13.2 V. If utility mode is selected (while parked) that charging voltage will be ~14.6 V.

GPM432 said:
the 12v battery gets low it is some how charged up from the main battery.
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Logic software installed in the VCULDC (Vehicle control unit low voltage DC) controls the charging of the 12V battery, and frequency varies depending on which version is installed.

From what I have gathered in this forum, particularly in the 12V battery thread, the "right amount" of 12V charging is a work in progress, as displayed by those posting visual graphs using a 12V monitor(BM2).
My current version seems to be working quite well, and have not experienced any issues, so far :)
 
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electriceddy said:
Heat pump, resistive PTC heater, air conditioner, inverter , on board charger, and HV battery heater (via the HV junction box) is directly supplied by the traction battery pack, all other electronics are supplied from the 12V system.


Starting the car initiates the HV battery contactor to close using the 12V system putting the car into "run" mode. When in run mode the voltage applied to the 12V battery is ~ 13.2 V. If utility mode is selected (while parked) that charging voltage will be ~14.6 V.


Logic software installed in the VCULDC (Vehicle control unit low voltage DC) controls the charging of the 12V battery, and frequency varies depending on which version is installed.

From what I have gathered in this forum, particularly in the 12V battery thread, the "right amount" of 12V charging is a work in progress, as displayed by those posting visual graphs using a 12V monitor(BM2).
My current version seems to be working quite well, and have not experienced any issues, so far :)
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Thanks for that my friend.

Well I hope it was the original Battery that was giving out. I bought a new CDN tire one and also a battery booster. I have owned lots of cars and the charging on the Kona is inadequate... My old ice cars batteries would last over 6 to 8 years. Plus as the battery got low the battery warning light never came on
 
If you install a BM2 Battery Monitor you'll learn a lot about what works and what doesn't. But I recognise that it's not for everybody. I check mine daily and have had yet to see a voltage problem the entire time I've owned the car, since Oct 2018.

I've never had to intervene but recently at 6°C the doors would not unlock until after a few tries and then the mirrors opened slowly. No issue with the battery voltage (13.0 V) though and it had just finished a scheduled charge event, so that incident remains unexplained. Once driving, the PTC cabin heater kicked-off creating a burnt smell as I don't think it's ever switched on before, drawing 3.8 kW!. 10 minutes later the heat pump took over.

Otherwise, to preserve the 12V charge, minimise the time doors are left open when the car is "off" and never leave the charger plug in the car if the charger itself is not powered up. Short drives (< 5 min) do take a toll. Placing the car in Utility Mode for an hour once a week might be beneficial to overcome that, if relevant.

If the car sits idle for over 56 hours the automatic charging drops to only 20 min a day. A short drive will kick it back into the normal routine, 20 min every 4 hours.

After charging, the 12V battery gets a minor beating for several hours as the BMS checks the main battery for signs of problems. A healthy battery should have no issue with that.

Interestingly, it seems that the Ioniq 5 is a bit more diligent and checks the 12V battery state more frequently, so maybe someone is listening. But there are still posts from those owners about dead batteries, much the same as we have had or years.
 
My Kona gets an hour scheduled charge daily, and only rarely is un-connected overnight. It remains connected if not being used for a day or two, sometimes a few weeks.
Two things I've noticed..
Charging never drops to 20 min/day if hooked up to a live connection..
If the car is not connected, any door opening kills an automatic charge, but a live connection allows the automatic charge to ignore a door opening..
 
For a month or so our 2019 has needed a boost pack to wake up. I've been to a couple local parts stores, where I was told "we can't even get the kind of battery your car takes" and yesterday, at the dealer they said "we can have one in 4-6 weeks". (I had to boost it in the dealership parking lot.)
I measured the battery and looked at a group-size chart (in addition to seeing this thread) and the OEM battery has the same dimensions as a 26R. I installed the same one as the OP - DieHard Red, 26R. Easy swap. I also fitted the plastic cover over the negative post (with a small bit of utility knife work). $110. Wish I'd done it a month ago!
 
NRH said:
For a month or so our 2019 has needed a boost pack to wake up. I've been to a couple local parts stores, where I was told "we can't even get the kind of battery your car takes" and yesterday, at the dealer they said "we can have one in 4-6 weeks". (I had to boost it in the dealership parking lot.)
I measured the battery and looked at a group-size chart (in addition to seeing this thread) and the OEM battery has the same dimensions as a 26R. I installed the same one as the OP - DieHard Red, 26R. Easy swap. I also fitted the plastic cover over the negative post (with a small bit of utility knife work). $110. Wish I'd done it a month ago!
Click to expand...

I have the negative cover off Can you explain how you got that cover on maybe a pic ?
 
GPM432 said:
I have the negative cover off Can you explain how you got that cover on maybe a pic ?
Click to expand...

So I did a meter test this morning on my new Battery it came in at 12.44volts. started the car put the radio on ac on and it then showed 14.87volts so I assume it is charging while it sits. Which is good. Then I tested the old battery it now sits at 13.07 with no load at all I thought it might loose some charge but it didn't .. I'll wait and test as the week progresses.
 
GPM432 said:
So I did a meter test this morning on my new Battery it came in at 12.44volts. started the car put the radio on ac on and it then showed 14.87volts so I assume it is charging while it sits. Which is good. Then I tested the old battery it now sits at 13.07 with no load at all I thought it might loose some charge but it didn't .. I'll wait and test as the week progresses.
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Generally bad batteries can still be charged to a high resting voltage, but the voltage immediately drops when you put a load on them.
 
GPM432 said:
I have the negative cover off Can you explain how you got that cover on maybe a pic ?
Click to expand...
My wife takes this one to work everyday, so I'd need to remember take a picture over the weekend. Briefly, here's a description - The neg terminal cover has a long tab, that extended down the right side of the battery. That tab can be inserted into the handle slot on the side of the DieHard battery (loopy handle removed). The tab has a right-angle support on the back of it, and I trimmed that back about 1/2" so that the tab could reach far enough into the battery's handle slot so that it would clip into place. To make the terminal cover sit right on top of the battery, I cut the round appendages that used to stick into the top of the old battery back to about half their previous length.
 
Great question. I wonder if the 'cold cranking amps' ends up being as much an indication of the quality of 12V battery itself, rather than the necessity of using those amps. But I have no idea about either the needs of the 12V system in these cars, or the quality of one 12V battery over another.
 
From what I can tell the battery group size for the Kona EV is 99R (also known as T4). It's good to hear that a 26R will also work. Checking prices online the 26R is less expensive than the 99R.
 
java said:
From what I can tell the battery group size for the Kona EV is 99R (also known as T4). It's good to hear that a 26R will also work. Checking prices online the 26R is less expensive than the 99R.
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26R slightly higher dimensions than 99R ~ 1", and 1/2 " longer. The cables attaching obviously have enough slack.
That would be my first choice as a replacement...when my turn arrives, hopefully later than sooner:rolleyes:
99R:
Maximum Overall Dimensions (L x W x H): 8-1/4" L x 6-7/8" W x 6-7/8" H (210 x 175 x 175 mm)
26R:
Maximum Overall Dimensions (L x W x H): 8-3/4" x 6-3/4" x 8" (222 x 171 x 203 mm)
 
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from what i can see, the size of the battery is because as the 12 volt supply it runs all of the cars 12 stuff ,light, heaters wipers etc.
and is not on constant recharge as it would be in a ice car, my Kona checked the battery voltage every 30 mins when the car is on <ie driving>
and every 4 hrs when the car is off or charging, so the bigger the size of the 12 volt the better as less volts drop between charging times.
 
NRH said:
Generally bad batteries can still be charged to a high resting voltage, but the voltage immediately drops when you put a load on them.
Click to expand...

WITHOUT GETTING ACLOAD TESTER IS THERE ANOTHER WAY i GET PUT THE BATTERY ON A LOAD ..
 
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