"Proactive" 12v battery replacement - good idea or overkill?

joebruin77

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My wife and I took delivery of my wife's 2022 MME GT in July of 2022. So far we have had no problems or issues with the car at all.

I recall reading in one of the tagged 12v battery information posts on this forum that 12v batteries usually last 2 to 2 1/2 years. Given that the 12v battery in our MME GT will be 2 years old this coming July, I am considering proactively replacing it even though the car is functioning fine.

My main concern is that I don't want the 12v battery to die unexpectedly, leaving my wife or me stranded and in need of a tow. I think replacing the 12v battery proactively would give me peace of mind.

What do you think? Is this a good idea or overkill?

Thank you,
Joe
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Shepherd

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I wouldn’t do it while the car is still under any kind of warranty. But that’s me. I wouldn’t be too put out by the low voltage battery failure such as being in a unsafe place. Ifyou need to for your peace of mind, it’s only a couple hundred dollars.
 

bshaw

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My wife and I took delivery of my wife's 2022 MME GT in July of 2022. So far we have had no problems or issues with the car at all.

I recall reading in one of the tagged 12v battery information posts on this forum that 12v batteries usually last 2 to 2 1/2 years. Given that the 12v battery in our MME GT will be 2 years old this coming July, I am considering proactively replacing it even though the car is functioning fine.

My main concern is that I don't want the 12v battery to die unexpectedly, leaving my wife or me stranded and in need of a tow. I think replacing the 12v battery proactively would give me peace of mind.

What do you think? Is this a good idea or overkill?

Thank you,
Joe
The battery life is going to depend on how well the car maintained the charge levels. Or more specifically how often you drove and plugged in so that the car could do its thing. Like any battery, colder temps and staying at a low state of charge would wear it out more quickly.
I'm at 3+ yrs and original battery still seems fine, I will wait until it konks out to replace it.

You won't need a tow if your 12V goes dead. A 12V jump source will be able to get you into the frunk and from there another jump would likely bring the HVB battery online and you could drive home or somewhere to replace the 12V immediately.
 

Mach-Lee

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I think I would wait my 3 years under warranty and then replace it. Most of the cars in SoCal can do 3 years unless the battery was abused.

Where I live, experience has shown batteries last around six years, which is when I replace them proactively. They still start vehicles, but my testing shows they have significantly reduced capacity (e.g. 50% of new) which increases the chance of having a dead battery.

It's sort of like tires, you don't want to wait until you hydroplane to replace them. Replace the battery when it shows signs of reduced capacity.

FYI, load testing the battery is not the whole story. A battery can test good for cranking amps, but have horrible capacity. Capacity is more important than cranking amps for an EV.
 
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RickMachE

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I would never replace a working battery, EVER.

As my batteries age, I start taking them to a local autoparts store, around October each year (prior to winter) and have a load test done. I never replace a battery without having a load test done.

My 2013 F-150 battery lasted 8 years, but I kept it on a Battery Tender. I will load test this battery just before 3 years, and then each year around October.
 


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I'm a monitoring nerd.
I would KNOW if the 12V battery is showing signs of not being up to the task.

Modern vehicles do tax the 12V battery in ways that just didn't exist yesterdecade. So I don't expect the lifespan of the battery to be as long as they used to be. But I'm also not going to replace one that isn't tired or injured yet.
 

Fins160

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I was thinking of doing this same thing, coming up on 2 years in November. Here in Phoenix, weonly get 2-3 years max out of a battery on our ICE vehicles. It’s primarily my wife’s car, so I first will modify the frunk area to allow easy access to the battery terminals so she can jump it if needed without having to remove all the panels. I will have a load test done this winter, and will likely do a proactive replacement next winter after 3 years if all goes well.
 

Teslaeata

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How very interesting just how different we all are.

My way is worry about nothing!

Never change unless necessary.

Never monitor, never “condition”.

The 12V battery lives ‘til it dies then I’ll deal with it.

My view is life’s just too short to worry about everything which might happen.

Each to our own, we’re each happy with our own way👍
 

HuntingPudel

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I still have the Optima battery I bought in 2002 powering my big Pontiac in the T/A. That said, my Fusion Energi’s 12V died before the car was in my hands for 6 months. None of the other 12V batteries I have had failed before 5 years. I am not worried about my MME’s 12V. It’s already passed the infant mortality window and as long as I do not have a charging issue (which is the main cause of 12V battery “failure”) I expect at least a couple of more years out of mine. 🤷‍♂️🐩
 

Homestead

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How very interesting just how different we all are.

My way is worry about nothing!

Never change unless necessary.

Never monitor, never “condition”.

The 12V battery lives ‘til it dies then I’ll deal with it.

My view is life’s just too short to worry about everything which might happen.

Each to our own, we’re each happy with our own way👍
Mark Twain Quote: I've lived through some terrible things in my life, some of which actually happened.
 

ChasingCoral

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Overkill. My battery from February 2021 is still working in Maryland despite being run down to zero by faulty first generation HVB to LVB software.
 

Monke

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My car gave out an error code several times for about a month while my MME was less than a year old. I don't recall the exact message but it was saying something similar to car was disconnected from Ford pass to preserve battery. I mentioned the warning to the service during my visit. Technician did a charge cycle test on the 12v battery and it failed so it was replaced under warranty. If you worry, you could stop by a dealership and ask them to test your battery. Auto part stores will test your battery for free but I'm not sure about dealerships.
 

bshaw

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The replacement 12V battery is $187.50 MSRP. (kinda expensive for what it is)
For something low cost, I would have no problem proactively replacing it, but for an expensive component, I will wait until replacement is absolutely necessary.
 

Aubury

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I hope when Ford does the next revision of their EVs they take the opportunity to replace the Lv lead acid battery with lithium (LFP with a built-in heater is the best option IMO). Would also be a good time to update the voltage to 16V or 48V like Tesla has done. There's no reason for an EV to use lead acid, aside from the commonality of circuit designs for 12V voltage busses and the relative cheapness of the batteries. They don't need the high crank amperage that lead acid provides to start things. But, personally, if you plan to keep the vehicle for the expected lifetime of it then the saved initial cost using cheaper lead acid would be more expensive having to replace the battery every few years. A lithium battery might be initially more expensive but it should last the lifetime of the vehicle.
 
 




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