[EV- Technician]

Get your car checked for parasitic drains. Anything over 50 mA needs a closer look to see what's drawing power when it's off.
Have you linked your car app to any other companies? Like your grid, charger, or charging network providers?

 

[EV- Technician]

I had my 12v Battery die a few days ago. What made it worse was that I was 240 miles from home in Mid Wales (UK). It was all good when I arrived at the cottage I was renting not long after lunch. I plugged the Type 2 cable into the car and the charger before I went inside.
Later on, I set the charger to activate at 01:00 and charge for 5 hours.
It didn't charge. The car was dead when I came to it in the morning.

Being miles from anywhere apart from a small railway station 0.5 miles away, I was a bit stuck. Getting recovered would take all day and I needed to be in that area later in the day (best man at a wedding) so I had to try something different. Thanks to the internet, I located a battery a train ride away (and a taxi to the store).

As I returned with the battery and lugged it up a hill which is no joke, I wondered if the act of plugging in the charger and later setting a charge time caused a drain on the battery that could have caused it to go flat? I did make it to the church on time. The previous post by EV-Technician is why I'm posting here.

Anyone have any thoughts on that idea?

I have a Yuasa battery with a 5 year warranty in the car. On my return from Wales I have my car booked in with the dealer for two recalls, one being the ICCU issue. The other is the limp home change.

Plugged in and waiting for session should not be the problem. 12V battery do experience premature wear in some instances, and FLA chemistry is not known for long life expectancy. Go with AGM chemistry for replacement. And once you get the chance have them look on history for ghost drains,ICCU keep 30 days off graph for this purpose and anything over 50 mA is suspect for check.

 

[EV- Technician]

Is this likely to covered by my warranty or at my expense. To add insult to injury, Kia service agents cannot see it for 2 weeks (no courtesy car) or weeks if I ask for a car.

Not very familiar with all EU countries and warranty.

 

[EV- Technician]

A smart sensor on the 12V battery's negative terminal is a potential suspect and requires inspection. Furthermore, a review of the vehicle's records for the past 30 days should identify instances of parasitic drain while stationary. Any current draw exceeding 50 mA is unacceptable and necessitates diagnostic testing to pinpoint the source of the 12V battery drain when the vehicle is not running.

 

[EV- Technician]

Request compensation from the grid provider for the damaged 12V battery, resulting from their excessive and unnecessary data collection.
Professionally, any grid provider failing to utilize smart EVSE technology for EV charging oversight is likely collecting far more data than is contractually permissible.
Vehicle application account credentials should never be shared with third-party providers, regardless of their data protection claims; a breach would leave your private information vulnerable.

 

[EV- Technician]

Stay away from any 12V battery that has independent BMS to control cells voltage balance and has ability to disconnect charging or discharging without any inputs to the vehicle can bus network.
LFP chemistry is definitely wrong choice for vehicles that are designed to maintain lead-acid chemistry battery.
Sodium-ion chemistry is also not good, because to make this Sodium-ion battery work ( vehicle low DC side should be able to charge this chemistry to 16V)
Aftermarket solutions that are advertising remaining energy for this type 12V battery chemistries are not providing the facts that you will operate on the fraction of SOC and energy that vehicle is able to use.
LFP chemistry.
You need 4 cells in series connection to achieve or mimic 12V lead-acid chemistry.
But here is the catch. On freezing conditions onboard smart sensor will call 15.1V and high current that LFP chemistry just doesn't like ( 0°C LFP chemistry BMS will turn off charging mosfets) and likely if not turned off will overcharge LFP cells.
At 3.775V per cell LFP cells will be overcharged. And they will definitely get damaged by high current that onboard DC-DC converter is doing ( for lead-acid chemistry in quite cold weather conditions 15.1V and high current is used to warm the 12V battery quickly).
And I have not even scratch the surface and have talk about ripple effect on the low DC electronics and can bus network when this type of battery is disconnected by own BMS and vehicle is exposed to the electrical noise from onboard DC-DC converter.
If you want better 12V lead-acid chemistry go with AGM ( there are multiple versions, for as long is AGM design it will be better than stock).