Has anyone replaced their 12V battery with lithium?

Kia Soul EV Forum

Help Support Kia Soul EV Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Speaking of batteries... Just wanted to give an update on my 2016 Soul EV+. It's been a great car for about a year, but a few months ago I started noticing that the range was dropping by one mile almost every time I charged at home. I chalked it up to the weather at the time (in Florida) being very hot (in the mid to upper 90s every day). It was hovering around 64 or so miles then. But then in August I went to unplug my car before going to work and I noticed that the EVSE on the wall had a blinking yellow light, meaning there was some kind of error. When I started the car the message "Charger Error" was there and the battery had not been charged at all. This error showed up every time the car was started, so not a fluke and no J-1772 charging would work. Luckily, I was able to stop at a local DC station and charge on the way to work, but the level 2 charger on the car was not working.

So, I immediately made an appointment with what I thought was the closest EV-certified Kia dealer at the time (more on this in a minute) which was 110 miles away as the crow flies, but much longer via actual roads... By then my safe range was about 55 miles so it was not fun getting there. Took me about 10 hours in total. Luckily I left the morning before my appointment and stayed in a nearby hotel so I only had a mile or so to drive the next morning to the dealership (Wallace Kia in Stuart Florida. They were totally awesome. Highly recommended if you live around there).

Anyway, they replaced the charger under warranty (lucky me because it cost over $2000 otherwise) and I was off to get back home. At first my range was showing 105 miles, which is more than I have ever seen on the vehicle (it would normally show 82-85 miles at 100%), so I was super happy. But, my happiness was short lived because on the way home that range was plummeting FAST. For the one and only time since I've had the car I actually ran out of charge and had to be towed 1 mile (yes ONE STINKING MILE) to the nearest DC charger.* No doubt the range had been reset when they replaced the charger.

After that my range continued to plummet though I could at least charge at home again and it finally settled around 39-41 GOM miles (45-50 actual). I didn't relish the idea of going through another ten hour drive so I did a lot deeper research and discovered that the Kia dealer closest to me that had not been EV certified before I bought it had recently been certified, so I took it there to have the battery tested. Analysis showed that I was hovering around 25% SOH. Yikes! And I can't imagine why because I drive it very normally, with very little highway miles and usually charging to 80% until the end there when every mile counted. I live only about 10 miles from my job too. I think the guys who had it before me must have abused the hell out the battery pack by maybe depleting it and DC charging it every day.

The manager had offered to supply me with a rental car while they waited for the battery pack to arrive. He originally thought it would be "a few days. Maybe a week" but today makes one full week. But I specifically asked them if I can keep the rental until my Kia is ready and he said yes, so that's fine with me! The rental is a 2022 Hyundai Sonata. Nice car, but not nearly as smooth and nimble as the Soul EV was/is. Looking forward to getting mine back, especially with full miles again (it appears it's going to be a new pack but we'll see).

I wonder how long the battery pack will REALLY take to arrive...

* Funny story. I struck up a conversation with the tow truck driver and we ended up talking about electric cars for almost an hour even though the tow only took about 5 minutes. He couldn't understand why a jump start wouldn't have helped me. I told him why the 12V accessory battery was there and that it was actually fully charged and working perfectly. After he left, an elderly Kia Soul owner, a 2021 ICE model, asked if she could ask me some questions about electric cars because she had heard "some bad things". By the time we got done we had talked for about 30 to 45 minutes and I answered all of her questions and told her about the great benefits of driving an EV. I'm 99% sure she is going to trade that thing in for an electric vehicle. LOL.
 
It is generally understood that the early batteries in SoulEVs suffered from the chemistry of the cells being susceptible to hot climates. Allegedly, the cells KIA now use (and are using in replacement batteries) are much more robust as well as being slightly higher capacity, so the nominal 27kWh of the 96 cell-pairs may be increased to 29+.
 
IanL said:
Quote from the Kia Service Manual:

"When replacing the battery, it should be same one (type, capacity and brand) that is originally installed on your vehicle. If a
battery of a different type is replaced, the battery sensor may recognize the battery to be abnormal."
Has it been confirmed that putting in a non-Hyundai Motor Group battery could actually threaten the warranty? Should I only get regular 12v batteries, and only at the Kia dealership, until the warranty period is over to be on the safe side? Or am I safe to swap out to lithium without any warranty hassles at the first opportunity?
 
I don't know that it's safe to assume that, but my KIA dealer hasn't blinked at the YUASA battery in mine. He's spent quite a few hours chasing a suspected brake fault at KIA's expense, so it doesn't seem to be an issue at that dealership.

I kept the original battery (still useable but below 60% SOH ) so could swap it back in if it became an issue for warranty service. It gets a maintenance trickle-charge every 3 months.
 
I've not had a single message from the car complaining about the dual parallel lithium 12V battery setup so far. I guess if it's pretty close to the specs of the original the car doesn't mind (same voltage and similar amp hours, etc). Mine is currently 12V (well, it tests at 13.3V, which is normal) and 40 Ah which is really close to what the original battery had. I think Kia is just hedging their bets in case someone wants to put a giant truck battery in there with 900CCA, etc.
 
Maybe it depends on the attitude of the dealership. There is only one KIA dealer on the little island where I live, but their attitude really is "the customer is King". Service prices aren't cheap tho'.
 
FLKiaEV said:
I've not had a single message from the car complaining about the dual parallel lithium 12V battery setup so far. I guess if it's pretty close to the specs of the original the car doesn't mind (same voltage and similar amp hours, etc). Mine is currently 12V (well, it tests at 13.3V, which is normal) and 40 Ah which is really close to what the original battery had. I think Kia is just hedging their bets in case someone wants to put a giant truck battery in there with 900CCA, etc.

I replaced my 2016 Soul EV+ 5+ year old 12V original Hyundai battery with a 12V 30Ah Deep Cycle LiFePO4 battery. It works fine except it does not appear to get charged by the vehicle. There are no messages and when the motor is turned on there appears to be a charging voltage. The car does not seem to need the 12V battery except when opening the doors and pressing the start button. I've resorted to a trickle charger for now and carry a lithium ion jumper battery if I should be stranded somewhere. Is there any way to trick the car into working with this battery?
 
There is a definite continuous draw on the 12V battery when the car is shut down - I assume its for the ICE and the "listen out for the keyfob" function. If the ICE is operated for some hours with the car off, and obviously also if the lights are left on, the battery will drain below start up condition.

My guess is that the lithium battery voltage characteristic (very flat till it falls off a cliff) does not allow the car to see that it needs charging. If that's right, I don't see any way past that. However, lithium batteries are best kept partially charged, rather than topped up, so you are probably fine with your maintenance cycle.

2nd thoughts: If you can see a charging voltage when the car is on, at what point do you think the battery should be charging, but is not? The 12V battery is normally charged when the car is on, and at some unspecified point when the propulsion battery is being charged. If you are monitoring the latter, you would need to monitor the entire process to detect when the charging is applied (if it is).
 
Back
Top