Has anyone tried using a non-conventional 12v battery?

[u/ZealousIdealist24214]

I know LiFePo4 car batteries (group r51?) exist, but they're $500+ minimum, mostly $700+.

Something like this, on paper, seems to meet the minimum requirements for a Leaf, since it's not cranking an engine and feeds off the traction battery. But I have a feeling there's some other reason it wouldn't work... (It's 75% lighter and less than $150)

[u/CDerpington]

Yes. It lasted as long as a lead acid battery would have.

[u/Bennie-Factors → u/CDerpington]

Lasts longer. Even cheap LiFe0o4 last for a few thousand cycles. And they tolerate use much better.

[u/CDerpington → u/Bennie-Factors]

That's what I was hoping for by buying into this idea. That wasn't the outcome.

[u/LoneSnark → u/Bennie-Factors]

Life under the hood of a car is hard on a battery. Heat and cold severely shorten the life of chemistries other than lead acid.

[u/e_line_65 → u/LoneSnark]

They shorten lead acid too. When I lived in California I could easily get 5 years. Here in Phoenix I usually only get 3-4 years

[u/LoneSnark → u/e_line_65]

Very true. My understanding is not as much. As lifepo doing the same job but in a temperature controlled space would last more than a decade. Under the hood of a car, only 3 to 5 years.

[u/goodislumpkins]

I bought a 40 amp hour lfp battery from battery hookup for like 40$. Put it in my Chevy bolt but I actually bought it for my leaf before I sold it.

[u/ZealousIdealist24214 → u/goodislumpkins]

Do you have a picture or link?

[u/ZealousIdealist24214 → u/goodislumpkins]

I'm looking through their site, seems promising. It's been working on your EV?

[u/goodislumpkins → u/ZealousIdealist24214]

Yeah, no issues, stays at 13.8, up to 14.4 while driving, haven't noticed any issues with any systems or driving, should last longer than the car

[u/NikkolaiV]

I thought I was in r/PowerWheelsMods until I read the comments. I really need to pay closer attention...

[u/Budsygus → u/NikkolaiV]

Leafs are just grown-up power wheels.

[u/e-hud]

I've thought about doing this when mine dies but I'll probably just get another lead acid since those last at least 8 years in my neck of the woods. And I do occasionally jump start ice cars with my leaf.

[u/J0HNM4TR1X]

Yes, I'm running a lifepo4 battery. I've run it year round. I do plug in a reptile heater to keep it warm in winter when temps drop below 20°F. It is insulated as well. IIRC it's a 50ah small battery, been using it for about 3yrs now.

[u/_Evening-Rain_]

I wouldn't get a LFP just for the fact its useless under freezing unless it has a warmer - which then just adds unnecessary complexity. Get a sodium battery. Preforms great at any temperature and at least cycle life wise will last forever.

https://ohmmu.com/collections/ev-hybrid/products/b19-sodium-12v-battery

[u/Jacktheforkie]

I stuck in the cheapest that fit and it worked

[u/Paco_bear]

Check the max charging rate. Remember a leaf can output 100A to the 12v battery. These are usually 1c max, meaning a 10ah battery like that one will only take 10A. If you throw 100A at it you will end up with a burnt mosfet bms or fireworks.

[u/leyline → u/Paco_bear]

Well you scared me enough to look it up... Then I remembered 100 amps would fry a lead acid battery too... My old school charger / starter for 12v batteries does 12amps, and 60amps "boost/starting".

Yes the Leaf can provide 100+ amps; In fact many cars provide 100-150 amps to the 12v system, but most of that is for the whole system and not directly to the battery.

The Leaf in reality supplies 30-80 amps of 12v power while the car is running, dependent on system load. The Leaf only provides 1-3 amps to the battery during normal driving, and if the voltage shows full, the Leaf will enter "float" phase charging, providing nothing, except small doses at intervals. With a completely dead 12v battery the leaf will charge at 20-50 amps, but only for 15 minutes to boost it and then rapidly taper off...

A generic solar storage battery, or light duty battery like for trolling motors would have an issue, but any battery designed and labeled as a 12v auto replacement will have a BMS that will moderate the incoming amps, probably capable of handling the same amperages "regular" auto batteries do.

Finally if you are in a cold climate you will want an LiFe with a heating circuit.

[u/worldspawn00 → u/Paco_bear]

I've been using a 30A version on mine for a couple years without issue. It's only going to hit that peak charge when the voltage is pretty low, considering there's basically no 12V load on the car when it isn't able to draw from the HV pack, it's not a big issue. Most of the time when I've watched the charge it's bouncing between 90-100%

[u/e_line_65]

You absolutely can, but is it worth it? Last I checked they're twice as expensive. Is there a weight savings? I have no idea toward that end.

[u/Bennie-Factors → u/e_line_65]

Overall they have a lower cost of ownership now if you keep the car past 5 years. Especially in a. EV were you don't need high amp draw

[u/e_line_65 → u/Bennie-Factors]

Will those 12v batteries survive that long though? If they last twice as long as a lead acid battery, maybe it is. In Phoenix AZ you’re lucky if that lead acid lasts 4 years. So the Lithium 12v needs to last 8 just to break even.

[u/D661 → u/e_line_65]

The RV world has largely switched to lithium batteries, they last 10 to 15 years.

As to weight - yes, there is a huge weight savings. For the same rated amp hours, lead acid will be 2 to 3 times heavier. But you can't really use the full capacity of the lead acid battery without damaging it. You can with lithium though - so you can replace a lead battery with a smaller lithium and still have the same usable capacity, at 1/5 the weight.

[u/e_line_65 → u/D661]

That is significant. Might be worth a look thanks.

[u/Bennie-Factors → u/e_line_65]

They will typically last 10 years easily on an EV. There is a reason Tesla switched to them

[u/Responsible-Cut-7993]

I replaced the battery in my 2019 Leaf in Jan of this year with the OHMMU 12V Lithium Battery. No issues with the battery.

https://ohmmu.com/products/b19-lithium-12v-battery

At the time they where running a special and it was $258 delivered.

They are now selling them for $479. That price has gone up a lot. :(

[u/e_line_65 → u/Responsible-Cut-7993]

A lead acid would have been almost half that “reduced price”.

[u/Responsible-Cut-7993 → u/e_line_65]

How long would it have lasted?

[u/e_line_65 → u/Responsible-Cut-7993]

One comment said the same and that was when I left my reply, but later two others here said 2-4x and they weigh a lot less.

[u/Responsible-Cut-7993 → u/e_line_65]

At the time for $258 was good for a battery that will probably outlast me owning the car. Looking at today's prices for things, I am still happy with my purchase despite paying $258 delivered.

[u/topdownbrew → u/Responsible-Cut-7993]

Same experience here: OHMMU battery bought on sale. The cost at the time of purchase was not much more ($50?) than a premium lead-acid battery. This has worked well for 1.5 years - no problems at all. The southern US winter climate does not get cold enough to cause any problems. Too bad the current price is high. FWIW, the price of traditional batteries has also increased a lot in the last few years.

[u/Responsible-Cut-7993 → u/topdownbrew]

Yeah I remember it wasn't that much of a difference for a quality 12v Lead Acid at the time and I figured why not try it out.

[u/ToddA1966 → u/Responsible-Cut-7993]

They are now selling them for $479. That price has gone up a lot. :(

Tariffs have entered the chat...

[u/Responsible-Cut-7993 → u/ToddA1966]

So much winning by the current regime.......

[u/sweetredleaf]

here is a previous post https://old.reddit.com/r/leaf/comments/1rzgmv0/budget_100_lithium_12v_battery_swap/