Has anyone replaced their 12V battery with lithium?

[FLKiaEV]

I saw a video on YouTube of a guy who replaced his 12 lead acid accessory battery for his Fiat 500e electric vehicle and he's not had any issues for at least 2 years. I would like to do this too with my 2016 Kia Soul EV+. Does anyone have any experience with this and if so, what battery did they use? The guy in the video used the ReLion RB20 (20ah LiFEPO4) lithium ion battery.

Here's the battery: https://www.ecodirect.com/RELiON-RB20-1 ... J0QAvD_BwE

And here's the YouTube video: https://youtu.be/X_0lFn9YFNg

Is there anything I need to watch out for before doing this? These batteries are supposed to last several times longer than lead acid batteries and have several other advantages too. Any thoughts?

Thanks!
Russell

[IanL]

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."

[FLKiaEV]

Same brand? That's interesting. The one in there now is from Hyundai's battery division. Might be hard to come by! But anyway, it shouldn't be detected as abnormal because it supplies the same power profile. In fact it's better than the included vehicle battery in pretty much every category (but you wouldn't want to use it in an ICE application because it's not designed for supplying cranking amps for a starter).

I got the battery yesterday. Smaller than I thought it would be, and only weighs about 6 pounds. The battery that's in the vehicle now looks like it's in excellent condition, so I will keep this one on hand just in case. I'm also looking through the warranty book to see if it would void the warranty.

Russell
Kissimmee, FL

[MassDeduction]

Same brand? That's interesting. The one in there now is from Hyundai's battery division. Might be hard to come by! But anyway, it shouldn't be detected as abnormal because it supplies the same power profile. In fact it's better than the included vehicle battery in pretty much every category (but you wouldn't want to use it in an ICE application because it's not designed for supplying cranking amps for a starter).

I got the battery yesterday. Smaller than I thought it would be, and only weighs about 6 pounds. The battery that's in the vehicle now looks like it's in excellent condition, so I will keep this one on hand just in case. I'm also looking through the warranty book to see if it would void the warranty.

Never heard of this before. Cool! I bought a used Soul EV, so no warranty concerns on my part, so I might swap it out immediately if it's that much of an improvement! An inability to kill the battery is pretty appealing. I wonder how big the SOC buffers on this thing are? 20%+ each end if we're really lucky.

[FLKiaEV]

I ended up with two of them because the first one had a tiny amount of red paste on one of the terminals (no big deal). So, they sent me a new one and said keep the first one! Anyway, this is what the final installation looked like after connecting them in parallel (so that I get twice the amp hours: 40 instead of 20 but still the same voltage):



So far no issues whatsoever, and I like having the peace of mind that it should last several times longer than a lead acid battery. I've tested the setup several times and it always reports around 13.4 V, which is ideal. One by itself would be fine too (unless you leave your headlights on for an extended period of time with the vehicle turned off), but I had it anyways and didn't want to waste it.

If you happen to do this, make sure you connect them in parallel and NOT in series! So, positive to positive and negative to negative will yield a 12V battery with the amp hours of both combined (20 + 20 = 40), which is what you want.

[MassDeduction]

They make "LT" (low temperature) variants of this battery. I wonder if that would be a better bet for me? I live in a very mild part of Canada, it rarely drops below freezing even in the middle of winter, but we do on very rare occasions get a winter cold snap that's below freezing. However, ReLiOn only recommends the 75 amp and up versions for electric vehicles, and they only make the LT versions in 20 and 100 amp versions (and the LT 100 amp is an eye-watering $1349!). I suppose I could two LT 20 amp in parallel, as was done by another person in this thread.

What is the ideal Ah for a Kia Soul EV 12V battery? I have access to 2016, 2017, and 2021 models, and am interested in doing this for any/all of them.

[FLKiaEV]

Well, I live in Florida so the parallel 20AH setup works well for me (it rarely drops below 30F). I'm the one who did the lithium setup above.

I can't imagine that 75AH would ever be needed unless they're talking about using a series of these batteries to power the vehicle itself, rather than as the accessory battery. After all, the 12V accessory battery that comes with the car is only about 45AH.

I've not had any issues whatsoever so far. If they offer a low temp version and the price is reasonable for a 20AH battery then you might try that. Since the demands on this battery will be quite low, for the most part, even 20AH will be fine 99% of the time. Just don't leave your headlights on for a long time without the main traction battery engaged.

Good luck.

[MassDeduction]

Well, I live in Florida so the parallel 20AH setup works well for me (it rarely drops below 30F). I'm the one who did the lithium setup above.

It's been a while since you posted about it. Any additional feedback about your lithium 12v installation? I'm hesitant to make the change unless and until the existing battery is nearing end-of-life, but might jump on board once the existing battery is a little longer in the tooth. Is it still treating you well?

[FLKiaEV]

No issues whatsoever. I tested them individually about a month ago and they were still showing excellent voltage (13.something IIRC). I will say that if you are planning on doing this with a parallel setup, do take the time to make sure that the batteries are voltage-matched before connecting them to each other (within a few hundredths of a volt if possible). For example, if you test one at 12.9 volts and the other at 13.3V, I would charge up the first one for a few minutes until it is closer to 13.3V so there are no imbalance issues right from the start (which can cause one to get a little hotter than necessary). Be sure to secure them to each very well and to the battery holder. You might have to get creative here...

And honestly, one 20AH battery will almost certainly be more than enough unless you're in the habit of running your headlights for a long time with the car turned off, or blasting the radio for long periods of time. I lucked out as to how I got the two that I have and was already expecting to use just one, which should be fine for virtually everyone.

[MassDeduction]

No issues whatsoever. I tested them individually about a month ago and they were still showing excellent voltage (13.something IIRC). I will say that if you are planning on doing this with a parallel setup, do take the time to make sure that the batteries are voltage-matched before connecting them to each other (within a few hundredths of a volt if possible). For example, if you test one at 12.9 volts and the other at 13.3V, I would charge up the first one for a few minutes until it is closer to 13.3V so there are no imbalance issues right from the start (which can cause one to get a little hotter than necessary). Be sure to secure them to each very well and to the battery holder. You might have to get creative here...

And honestly, one 20AH battery will almost certainly be more than enough unless you're in the habit of running your headlights for a long time with the car turned off, or blasting the radio for long periods of time. I lucked out as to how I got the two that I have and was already expecting to use just one, which should be fine for virtually everyone.

Score! ReLiOn has rolled out a 50 Ah LT (low temperature) battery. It's about twice the price of the 20 Ah LT battery, so more desirable (in a few ways) than a 2x20 Ah set-up. Obviously your 2x20 set-up was better for you as one of them was free!

Interesting that the stock battery is in the 45 Ah range, despite your understanding that even 20 Ah would be satisfactory for most people. I guess they've built in some redundancy that way. The 50 LT is the sweet spot anyway, about double the price of the 20 Ah, but slightly less than half the price of the 100 LT.

How long is the stock 12v likely to last? It's commonly said that 3-5 years is typical for 12v batteries in cars, but the #1 stressor is being used as a starter battery in an ICE car. Perhaps it'll last even longer in an e-car?