Fixed my battery issue (science'ish, not speculation)

Cautionary Tale

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Before I get into this, I'll preface with YMMV but this fixed my battery issue (thus far) and I'll continue to keep an eye and update this thread as the days go on.

My battery charge level constantly varied between 12-14.3 and jumped erratically all around there. Twice it took to tries to start engine and came up with red battery dash light. 2 nights ago the science began...

Controls:
- My fobs and digital key in Faraday bags, and inside a faraday box. I tested this and no signal is getting out of the double wrap (didn't even try single wrap, to avoid variables)
- Auto-stop start is disabled (to further isolate possible issues)

Variables:
- Amount of time vehicles sat between being driven
- Distance driven, and traffic conditions
- Probably more that I'm not thinking of at the moment

I first tested both the main battery and Aux battery with multimeter (sorry no pics, as doing this solo required more hands than I was given.)
- Main battery: 12.01 - 12.04
- Aux battery: 12.13

First experiment (only thus far)
- Used NOCO Genius10 charger to charge both AGM batteries and allowed it to complete an optimization cycle. (12 hours for both, approx.)

Results (posted)
- Main Battery charged to 14.77
- AUX Battery charged to 13.38

I spent the day driving around with mix of short errands and longer drives my observation:
- Battery no longer fluctuated wildly and instead maintained charge, with only the slightest of deviations. As the battery settled throughout the day, I found it maintained 14.4 and no dash lights or any problems whatsoever.

I'll continue to test battery levels daily and if I see declining levels, I will repair both batteries and test that.

Notes: The aux battery negative terminal showed signs of corrosion which is extremely odd. It wasn't enough to clean but obvious signs of pitting.

Hopefully this helps some of you.
 

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Thank you! I’ve got a Lithium Battery for my truck - so it’ll be fun replacing it… but I need to get a lithium aux battery as well :).
Maybe it's a stupid question, but I prefer to ask before I'm left with doubts... what's the difference between lithium batteries and normal ones?
 
Maybe it's a stupid question, but I prefer to ask before I'm left with doubts... what's the difference between lithium batteries and normal ones?
No such thing as a "normal" battery. Our batteries are AGM, then there are Lithium and the older style Lead batteries which are most common so "normal" I suppose.

Update today: Batteries are happy and main is maintaining 14.5. I need to test the aux battery and if it's dipped I'll rebuild it this weekend...if I can find spare time
 
I bought (2) of these units and its really nice to monitor by just opening an app on cell phone. I like the SOC (state of charge), voltage and temp. Can monitor 4 batteries all at once.

 

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I bought (2) of these units and its really nice to monitor by just opening an app on cell phone. I like the SOC (state of charge), voltage and temp. Can monitor 4 batteries all at once.

That is clever and looks like your batteries are heading to the mystical land of warranty replacent, assuming the app is as accurate as multimeter. My main holds 14.5-14.75 and Aux is 13.1-13.6.

Have you tested its accuracy against multimeter? If it's accurate I'm all about it.
 
That is clever and looks like your batteries are heading to the mystical land of warranty replacent, assuming the app is as accurate as multimeter. My main holds 14.5-14.75 and Aux is 13.1-13.6.

Have you tested its accuracy against multimeter? If it's accurate I'm all about it.
Funny thing. These are both replacement batteries. I also did what you did. I put my fob and key card in a faraday box. I can charge the battery and I will still loose overnight.
The app is following along with a volt meter. I kept both OEM batteries maybe I should try the recondition with my NOCO charger.
 
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Funny thing. These are both replacement batteries. I also did what you did. I put my fob and key card in a faraday box. I can charge the battery and I will still loose overnight.
The app is following along with a volt meter. I kept both OEM batteries maybe I should try the recondition with my NOCO charger.
LOL, well I'm glad I didn't get replacement batteries then.

Excellent info, thanks!

Just make sure if you recondition your battery, that it's out of your truck and NEEDS to be fully charged. I'm sure it says so somewhere but just in case. Only we can prevent forest RHO fires ;)
 
You made me just go check. The app voltage and Klein multimeter reports back the exact same voltage. I dont know WTF is eating voltage overnight. I have deleted the RAM app, put fob in faraday box, and turned off proximity on the Uconnect. What else is left? I also tried the battery long term storage. While it didn’t loose near as much in that mode its kinda a PITA, you have to unlock the doors with the actual key to get back in.
 
What do those run $$-wise?
I would like to know that as well. I have bought a few for kayak electronics and an inverter setup in a Jeep but neither one of these are the right size to fit on either the main or the auxiliary. I dont live in a cold climate so should prob work good for me.
 
You made me just go check. The app voltage and Klein multimeter reports back the exact same voltage. I dont know WTF is eating voltage overnight. I have deleted the RAM app, put fob in faraday box, and turned off proximity on the Uconnect. What else is left? I also tried the battery long term storage. While it didn’t loose near as much in that mode its kinda a PITA, you have to unlock the doors with the actual key to get back in.
I have the RAM app loaded and don't have the bleed. I do have my keys in a faraday box with faraday cases over them and pretty far away from my truck, just in case signal managed to escape, though I did test the box, and it passed my basic tests.
What do those run $$-wise?
I was working with Odyssey for their battery options that would work with us. I just need to touch base with the rep again, as she needed some dimensions that were outside of my caliper's capability. Odyssey, from what I've read and heard is a great battery company. Apparently, Optima has fallen in quality in recent years, which would make sense as my local shop that used to carry a ton of them now only has a handful. Of course, this is all hearsay and speculation as I've not had a new Optima in a few years now.
 
I have a Jeep bud that swears by the odyssey battery. Just like me we use to always run Optima but also have heard of quality issues. I have a red top from 2018 that still holds charge. Also have a newer blue top in a 69’ mustang.

I do have the stock batteries in the garage let me know if you need physical dimensions.
 
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