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mr.Magoo

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Over time, going down to 50% or 40% before topping off will take its toll.
Going below 90% for 4 days is not a good thing for the battery.
Where do you find this information?
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jwrezz

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OK, so it's not a backup for the truck itself, it's a backup for my data logger / dash cam.
It's placed where the OEM jack used to be and I have a separate DC/DC charger to maintain it.
So someone DOES have their battery in the rear seat!
 

mr.Magoo

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jwrezz

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Did I miss a question at some point ?

I'm not using any of the Ford Aux / 2nd battery stuff, this is just something I cobbled together on my own.

https://www.f150lightningforum.com/forum/threads/12v-battery-replacement-with-h4.35340/post-658128
No, my reference to the OP saying "rear seat" and my confusion thinking that they had their LVB in the rear seat of the vehicle. They were referring to the seat of the battery tray that that grabs the back of the battery before the hold-down is installed.
 

jwrezz

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The tray in my 2024 Lariat was a bit diff. On the right rear corner 2 pieces needed to be cut. On the left it was 4 pieces.
Ford F-150 Lightning 12V Battery replacement with H4 BatteryTrayCuts


Ford F-150 Lightning 12V Battery replacement with H4 LeftRearHoldDown


Ford F-150 Lightning 12V Battery replacement with H4 RightRearHoldDown


Ford F-150 Lightning 12V Battery replacement with H4 H4batteryInstalled
 
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DreamBrother1

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Seems like people are having good success with the H4 AGM upgrades. Anyone put an Interstate MTX-H4 in their truck, or know if it would work?
 

jwrezz

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Seems like people are having good success with the H4 AGM upgrades. Anyone put an Interstate MTX-H4 in their truck, or know if it would work?
It would work, 100%. Mine is not the interstate as seen by my pics, but if it's an H4, with the tray modifications, any brand will fit/work.
 
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Blochead21

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I just did this with a Walmart Everstart H4 AGM. Rockauto was 180 with shipping for an H3 AGM, and Costco didn’t stock and couldn’t order any Interstate H3 AGMs or H4 AGMs. However it’s a simple upgrade with just an oscillating tool, and for $189 at Walmart with a 4 year warranty it’s hard to beat.
 

RLXXI

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I just did this with a Walmart Everstart H4 AGM. Rockauto was 180 with shipping for an H3 AGM, and Costco didn’t stock and couldn’t order any Interstate H3 AGMs or H4 AGMs. However it’s a simple upgrade with just an oscillating tool, and for $189 at Walmart with a 4 year warranty it’s hard to beat.
Both show the local store to get or order from on my screen.
Interstate H3
Interstate H4

You're better off sticking with the Walmart battery (Johnson Controls) same maker of Motorcraft and many others. Walmart at least you know you can find one open at just about any hour of day or night in practically every suburb and city. Comes in handy at 5am when you're off to work and your truck won't start. Don't ask me how I know :angel:
 
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Blochead21

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Both show the local store to get or order from on my screen.
Interstate H3
Interstate H4

You're better off sticking with the Walmart battery (Johnson Controls) same maker of Motorcraft and many others. Walmart at least you know you can find one open at just about any hour of day or night in practically every suburb and city. Comes in handy at 5am when you're off to work and your truck won't start. Don't ask me how I know :angel:
You have to go through Costco directly they have the link online with different stock. My local costcos didn’t stock anything lower than an H6 and wouldn’t order it for me. They told me to go through the site, but the site wouldn’t allow me to order it anyway. Which is half the reason I went with an H4 to be able to find future batteries easier.

https://www.costco.com/automotive-batteries.html
 

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You have to go through Costco directly they have the link online with different stock. My local costcos didn’t stock anything lower than an H6 and wouldn’t order it for me. They told me to go through the site, but the site wouldn’t allow me to order it anyway. Which is half the reason I went with an H4 to be able to find future batteries easier.

https://www.costco.com/automotive-batteries.html
If you click the location tab on the battery website, it should populate many places to buy or order thru, mine shows 20 different stores within 10 miles of my location. But as I said previously Wallyworld hooked me up at 5am with a warranty replacement.
 

chl

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Where do you find this information?
Where can YOU find it you mean?

Any reliable battery manufacturer or tech battery course material about how lead-acid battery chemistry works.

I guess I first learned a lot of this information around the winter of 1979 in one of my first engineering courses in college - lead acid batteries haven't changed all that much, they work the same as forever.

"Lead-acid batteries were invented in 1859 by French physicist Gaston Planté. It was the first rechargeable battery (secondary cell) ever created, featuring two lead plates immersed in sulfuric acid. Later improved in 1880 by Camille Alphonse Faure, this technology remains widely used today in automobiles and UPS systems."

The Baghdad battery used an acid and two different metals, a copper cylinder and an iron rod, to produce the movement of electrons maybe 250 or more BCE, so they tell me, maybe the first wet cell battery!

I think if you searched on line for something like..."What causes lead acid batteries to stop working" you likely find the answer is most often, "sulfation due to leaving them in a discharged state." The other answer would likely be "heat or overcharging causing a loss of electrolyte."

It is kind of common knowledge among EE's I suppose.
 

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Where can YOU find it you mean?
It's been a month since I made that statement and it was not about battery design or chemistry in general, it was related to your statement that going below 90% for four days was bad.

While "below 90%" technically could be anything between 89.9999 and 0%, I doubt that 85% for four days is a big deal, so the statement seemed rather sweeping / generalizing and I simply wondered, where you get that information from, because not many sources talk about as low DoD as 10%

You're basically saying that any battery older than a year is "damaged" since their internal discharge rate would have brought them below 90% and at that point 4 days is nothing.
 

chl

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It's been a month since I made that statement and it was not about battery design or chemistry in general, it was related to your statement that going below 90% for four days was bad.

While "below 90%" technically could be anything between 89.9999 and 0%, I doubt that 85% for four days is a big deal, so the statement seemed rather sweeping / generalizing and I simply wondered, where you get that information from, because not many sources talk about as low DoD as 10%

You're basically saying that any battery older than a year is "damaged" since their internal discharge rate would have brought them below 90% and at that point 4 days is nothing.
I see...I should clarify that it is cumulative.
I meant to imply that, but should have said it explicitly.
Sitting at 85% over and over definitely is not going to be good for the battery.

In essence, to fully drive off the sulfates that form during the discharge process, the battery has to be charged back up to 100%.

One time is not going to kill the battery of course.
Doing that week after week will take it's toll, as all the battery failures in Lightnings lately are proving I believe.

Overcharging can also be a problem with AGM batteries especially - distilled water can be added to a flooded battery easily.

---
Myth: The worst thing you can do is overcharge a lead acid battery.

Fact: The worst thing you can do is under-charge a lead acid battery. Regularly under-charging a battery will result in sulfation with permanent loss of capacity and plate corrosion rates upwards of 25x normal. Overcharging a battery breaks down any sulfation, but can cause plate corrosion rates to increase up to 3x normal. With flooded/wet batteries you can always add water. One concern is overcharging AGM batteries, which already have very little water reserve, and so there is risk of dry-out. However, most chargers sold today are “smart” chargers and will shut off after the battery is fully charged.

https://www.advancedbattery.ca/8-myths-and-facts-about-lead-acid-batteries/
----

I hope that clarifies things, sorry I was not clearer about the cumulative effect. :)
 

jwrezz

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One concern is overcharging AGM batteries, which already have very little water reserve, and so there is risk of dry-out. However, most chargers sold today are “smart” chargers and will shut off after the battery is fully charged.

https://www.advancedbattery.ca/8-myths-and-facts-about-lead-acid-batteries/
---
Damned if you do damned if you don't! Good things we have DC/DC converters that will keep our batteries perfect for ever! Not!!!
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