[smoove ride]

FYI, an agm battery is a lead acid battery but with woven fiberglass inside to reduce stratification that you get in liquid lead acid batteries. Since the kwh charge rate is lower for an agm than a regular battery your comment that the hv converter kills a regular battery but wouldn't harm an agm battery simply isn't correct. If the hv battery maintainer kills any 12v battery in your car, take it to the dealer.

Not trying to argue with you, but I can only repeat my experience and that of the collective Leaf Forum's wisdom. Whatever the older Leafs have their charge program set for the 12v batteries, it seems to prematurely wear the batteries that came with the car (regular lead-acid). Untold numbers of other folks on that forum who have replaced them with AGMs have not had any more issues of premature battery wear. This is not a scientific, control group study.. but the result is the result.

With that said.. I have no idea if the EV6 will do the same or be perfectly fine? I imagine the evolution of the tech and real world feedback has smoothed out the issues the early Leafs had with 12v battery charging. Fingers crossed!

 

[ronsk74]

Not trying to argue with you, but I can only repeat my experience and that of the collective Leaf Forum's wisdom. Whatever the older Leafs have their charge program set for the 12v batteries, it seems to prematurely wear the batteries that came with the car (regular lead-acid). Untold numbers of other folks on that forum who have replaced them with AGMs have not had any more issues of premature battery wear. This is not a scientific, control group study.. but the result is the result.

With that said.. I have no idea if the EV6 will do the same or be perfectly fine? I imagine the evolution of the tech and real world feedback has smoothed out the issues the early Leafs had with 12v battery charging. Fingers crossed!

Sounds like nissan put some cheap thin plated 12v batteries in the leaf. You can't judge what all manufacturers do by one makers bad example and you shouldn't use that example to compare battery types. There is a lot of literature on lead acid batteries including agm available for the reading, and you get what you pay for.

 

[avh]

If the 12V battery is going to give me trouble I might consider replacing it with an equivalent lithium based battery like this one H5/Group-47 Lithium Car Battery – Antigravity Batteries
These are still expensive but lighter and they have a built-in BMS that should help.

 

[DMiller]

I think the lower capacity of those would cause more problems. If you use the Accessory mode much the OEM battery can delivery its 60Ah to run the lights, radio, infortainment, wifi, etc. Those lithium batteries are between 24 and 40Ah, so they can't provide power as long.

 

[avh]

Thanks DMiller this is a very valid point, I forgot that the original battery can supply 60 Ah. I can't seem to find a lithium battery that provides enough amperage in this group size.

 

[alexw]

Some more info:

Under normal circumstances, if nothing's faulty, you should be perfectly able to park the car for months, and it'll keep the 12V battery topped up that whole time despite its modest continuous drain for things like telematics and smart key radio comms. One forum user has already tried it for like 2 months and it was no problem when they got home: Main Batteries deplete when parked for several days

I also found some additional info in the manual over here: Interesting info about aux battery automatic recharging

The gist is, if the 12V battery is determined to be faulty, the automatic top-up logic will STOP doing that, so as to just let the 12V battery die and avoid deeply deeply depleting the HV battery over time fighting a loosing battle. The question is how that fault is determined. The manual says "if the system comes on 10 times in a row, it'll shut off permanently until the car is re-started." Except "10 times in a row" is extremely ambiguous. Is that "after the 10th recharge it stops ever recharging" i.e. if it tops up every 2 days, you can only park 20 days without issues? Or is it "10 times in a day" i.e. if there's a ton of drain on your 12V battery, it'll stop trying to top it up?

I intend to test with a constant dummy load attached to the 12V, but I haven't had long enough to get a good "normal operation" baseline yet.

 

[msg]

Some more info:

Under normal circumstances, if nothing's faulty, you should be perfectly able to park the car for months, and it'll keep the 12V battery topped up that whole time despite its modest continuous drain for things like telematics and smart key radio comms. One forum user has already tried it for like 2 months and it was no problem when they got home: Main Batteries deplete when parked for several days

I also found some additional info in the manual over here: Interesting info about aux battery automatic recharging

The gist is, if the 12V battery is determined to be faulty, the automatic top-up logic will STOP doing that, so as to just let the 12V battery die and avoid deeply deeply depleting the HV battery over time fighting a loosing battle. The question is how that fault is determined. The manual says "if the system comes on 10 times in a row, it'll shut off permanently until the car is re-started." Except "10 times in a row" is extremely ambiguous. Is that "after the 10th recharge it stops ever recharging" i.e. if it tops up every 2 days, you can only park 20 days without issues? Or is it "10 times in a day" i.e. if there's a ton of drain on your 12V battery, it'll stop trying to top it up?

I intend to test with a constant dummy load attached to the 12V, but I haven't had long enough to get a good "normal operation" baseline yet.

Any updates? Potentially scooping a Wind AWD and this whole 12v dying thing is freaking me out.

Plus, what I don't get is, if the 12v dies while the car is plugged in to charge, why doesn't the car continue charge? Then you use your portable jumper you were smart enough to buy bc of these 12v drain issues, but you have no more range stored than when you left the car to charge.

 

[ronsk74]

Any updates? Potentially scooping a Wind AWD and this whole 12v dying thing is freaking me out.

Plus, what I don't get is, if the 12v dies while the car is plugged in to charge, why doesn't the car continue charge? Then you use your portable jumper you were smart enough to buy bc of these 12v drain issues, but you have no more range stored than when you left the car to charge.

The 12v bus powers the battery management system which controls the charge of the high voltage battery. My 12v battery went dead 30 minutes after the start of a hv charge and the hv charge just stopped and would not restart until I recharged the 12v battery. Fortunately I was at home and it has acted normally since.

 

[msg]

The 12v bus powers the battery management system which controls the charge of the high voltage battery. My 12v battery went dead 30 minutes after the start of a hv charge and the hv charge just stopped and would not restart until I recharged the 12v battery. Fortunately I was at home and it has acted normally since.

Thanks for the intel! So ... Assuming I get this (which would be my first EV) ... I now know I gotta buy a portable jumper.

What else can I do to prevent the 12v from being a brick?
In my experience, once they've bricked once, it's only the beginning of the end for that battery.

 

[ronsk74]

Thanks for the intel! So ... Assuming I get this (which would be my first EV) ... I now know I gotta buy a portable jumper.

What else can I do to prevent the 12v from being a brick?
In my experience, once they've bricked once, it's only the beginning of the end for that battery.

I haven’t purchased a jumper yet but I did buy a battery monitor and am 3 days into collecting data on what the battery management system does with the12v battery when the car sits as well as when its driven. 3 days is nowhere near long enough to know all about how this BMS system functions but if it fails again I'll have data to be able to ask Kia the right questions.

 

[msg]

I haven’t purchased a jumper yet but I did buy a battery monitor and am 3 days into collecting data on what the battery management system does with the12v battery when the car sits as well as when its driven. 3 days is nowhere near long enough to know all about how this BMS system functions but if it fails again I'll have data to be able to ask Kia the right questions.

As they say, not all heroes wear capes.

 

[ronsk74]

As they say, not all heroes wear capes.

I'm no hero, I just want to know like everyone else what's happening. I suspect Kia may need to upgrade firmware for the BMS to protect the state of the 12 volt battery better. At the very least there should be a warning sometime before it goes dead and there isn't one now.

 

[msg]

I'm no hero, I just want to know like everyone else what's happening. I suspect Kia may need to upgrade firmware for the BMS to protect the state of the 12 volt battery better. At the very least there should be a warning sometime before it goes dead and there isn't one now.

Amen. Not comparing to Apple in terms of apples to apples (pun intended), but that's how I feel about my wireless keyboard and mouse from Apple. I'll sit down to do hours of work and get started then a few minutes in MOUSE 5% BATTERY. Welp ... Guess I'll read about EV6 on my phone while the mouse charges 😬

Also, it seems people are chattering about the 12v not charging if HV is <30/35%, but if you park your car and HV is low, then are you just supposed to accept that you may have a brick when you return?

It's all new to me.

 

[ronsk74]

Amen. Not comparing to Apple in terms of apples to apples (pun intended), but that's how I feel about my wireless keyboard and mouse from Apple. I'll sit down to do hours of work and get started then a few minutes in MOUSE 5% BATTERY. Welp ... Guess I'll read about EV6 on my phone while the mouse charges 😬

Also, it seems people are chattering about the 12v not charging if HV is <30/35%, but if you park your car and HV is low, then are you just supposed to accept that you may have a brick when you return?

It's all new to me.

It's 3 months new to me too, though I have experience with a lot of battery types working for the DOD, none with EV batteries. Even at 30% charge on the HV battery you should get more than 50 charges on the 12v battery before the HV battery even gets to 10%. Sitting idle mine charges the 12v battery about every day and a half, when it gets down to about 80% or about 12.2 volts. That should let it sit for months if you charge the HV battery to 80% before parking it long term.

 

[avh]

I left my car parked for a week and it went into "hibernation". I was checking Kia Access app every other day and this has not prevented it. The car is not plugged in and the high voltage battery was at 49% when I left.

So far I have not experienced the 12V battery drying but I bought a small Lithium jump starter like I would do for a gas car.

The car has the latest software and I have not seen this battery-saving feature mentioned before on the forum. I wonder if this is a new feature. It kind of negates the whole remote connectivity thing. A week is pretty common to leave the car parked for a vacation or business trip.

 

[ronsk74]

I left my car parked for a week and it went into "hibernation". I was checking Kia Access app every other day and this has not prevented it. The car is not plugged in and the high voltage battery was at 49% when I left.

So far I have not experienced the 12V battery drying but I bought a small Lithium jump starter like I would do for a gas car.

The car has the latest software and I have not seen this battery-saving feature mentioned before on the forum. I wonder if this is a new feature. It kind of negates the whole remote connectivity thing. A week is pretty common to leave the car parked for a vacation or business trip.

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View attachment 6536

That's interesting. This is what I would have expected mine to do before it died but I got no warnings. All this happened before the recall update and Kia may have made some changes regarding how it protects the 12v battery but if there is plenty of HV charge left it should just initiate a charge.

I was also surprised at the effect on the 12v battery when you poll Kia Access. Things turn on in the car and the battery voltage drops about .3 volts for 3 to 4 minutes then everything shuts off again. The same thing happens when I walk up to the car with the key in my pocket but I don't get in. The mirrors pop out and the car wakes up, the voltage drops about .3 volts again due to load for about 3 to 4 minutes then shuts off. I took a screen shot of it.

 

[HiThere!]

I asked this question almost 2 months ago and I love all of the information still coming in on this topic! It's seriously like having a new set of friends that I can pick their brains and share information/experiences. I've read every post. I may not have understood all of them (see original post, so true 🤣 ) but all have given me knowledge I didn't have 2 months ago. Thank You all SO much!

 

[msg]

Everyone recommends getting a portable charger for your EV or ICE, but they aren't supposed to be stored at high temps. Thoughts?

 

[alexw]

Not super surprising, but I have a little update at my own 12V thread: 12V battery self-recharge plot
TL;DR, got sick, left car sitting for 5 days waiting for the battery to die, and after having my liftgate open for a few minutes to vacuum, it did. Jumped easy enough, but now I'm jumping through annoying hoops to get the 12V charged up again.

Everyone recommends getting a portable charger for your EV or ICE, but they aren't supposed to be stored at high temps. Thoughts?

You mean portable JUMP box, yeah? True, but probably not that concerning - most lithium ion batteries I know of specify a storage temp of 60C. It's not GOOD for them, but it's also not acutely dangerous. Someone the other day measured their frunk on a hot sunny day at 50C or so. It's not comforting, but I don't personally feel concerned storing it in the frunk, or inside the center armrest which is arguably worse depending on conditions.

 

[msg]

Not super surprising, but I have a little update at my own 12V thread: 12V battery self-recharge plot
TL;DR, got sick, left car sitting for 5 days waiting for the battery to die, and after having my liftgate open for a few minutes to vacuum, it did. Jumped easy enough, but now I'm jumping through annoying hoops to get the 12V charged up again.



You mean portable JUMP box, yeah? True, but probably not that concerning - most lithium ion batteries I know of specify a storage temp of 60C. It's not GOOD for them, but it's also not acutely dangerous. Someone the other day measured their frunk on a hot sunny day at 50C or so. It's not comforting, but I don't personally feel concerned storing it in the frunk, or inside the center armrest which is arguably worse depending on conditions.

I was thinking frunk if I get one as well.