Diehard Platinum: < 1 Year Old and Already Leaking

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gathermewool

gathermewool

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Info:

-'08 STI
-Ditched the OEM Subaru Battery for Diehard Platinum
-Diehard in service ~8 months
-Corrosion, as shown below
-Sears says they won't replace it unless the battery fails, and that it's impossible for their, "gel glass mat batteries to leak from the top." I thought gel and AGM were two totally different things
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The original Subaru wet-cell battery in my STI was leaking around the posts, was giving me slow starts, and continued to show as needing a charge at the dealer (even after long road trips AND charging evolutions,) but they said that they would not be able to replace it under warranty unless it failed their test.

Instead of dealing with the headache of trying to get them to replace it (or the morality of killing the battery myself,) I spent the money and bought a new Diehard Platinum from Sears back in January. I figured my days of acid corrosion were over (AGM vs wet cell,) and that I'd be able to quit worrying about the battery for a long time to come. I guess I was wrong...

BatteryTopTerminals.jpg

BatteryTieDownCorrosion.jpg


I should have taken a picture after spraying the front of the battery with CRC Battery Cleaner. While the entire top of the battery didn't show colorfully like the OEM Subaru battery, it did show that there was acid all along the front of the battery. I took these pictures last night. I called Sears and they said they won't replace it unless the battery is failing, which it is not.
 
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Diehards are the worst batteries with the best warranties. Return it and get another one. When your warranty expires buy another brand.
 
Originally Posted By: OldCowboy
Sounds like you need to clean it twice a year and replace it with something else when it fails.


According the lady at Sears Auto I spoke with, it's impossible for these "gel" batteries to leak there, but still, they won't replace the battery due to corrosion.

I'll let it corrode again, then take it on over and make a stink.
 
I just popped the hood and, less than 24 hrs later, the same area is corroded. There's not nearly as much of the white powder present as initially, but it's still there.
 
Awful dirty for being such a new battery. Something else may be wrong. Can you measure AC ripple on the battery? Alt voltages OK?
 
Originally Posted By: JHZR2
Awful dirty for being such a new battery. Something else may be wrong. Can you measure AC ripple on the battery? Alt voltages OK?

I am curious on what the ripple tolerance would be on a battery?
 
Originally Posted By: JHZR2
Awful dirty for being such a new battery. Something else may be wrong. Can you measure AC ripple on the battery? Alt voltages OK?


Do you have an oscilloscope that I can borrow?
48.gif


Alt voltages logged between 13.8-14.5VDC, with 14.1-14.3VDC common.
 
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The diehard platinum is just a rebadged odyssey battery witch should be a good quality battery.

They are AGM witch means the electrolyte cannot leak. Even if the case breaks there shouldn't be a leak because there is only enough electrolyte in there to saturate the glass mat and that it.

My guess is the battery is being overcharged and gassing and thats whats causing the corrosion.
 
Originally Posted By: kasedian
There are ways to "fail" a battery. Ideas all over the web.


I brought this up back when I was first having issues with my OEM Subaru battery, and decided that I couldn't just kill a battery. In my mind, the battery may have lasted another year or more, albeit with slower starts in the winter, so it was on me to replace the battery if I wanted a new one earlier. I just couldn't purposefully kill it just to get a new one, in other words.

Originally Posted By: CDX825
The diehard platinum is just a rebadged odyssey battery witch should be a good quality battery.

They are AGM witch means the electrolyte cannot leak. Even if the case breaks there shouldn't be a leak because there is only enough electrolyte in there to saturate the glass mat and that it.

My guess is the battery is being overcharged and gassing and thats whats causing the corrosion.


The batteries are supposedly under-saturated, meaning they have excess capacity for electrolyte. I understand this part, but how high does the temperature need to get before the reliefs lift to lower pressure? In other words, the electrolyte should always stay contained in the battery unless, like you said, the battery charge rate is too high and causes Hydrogen buildup to the point that the relief valves lift.

The thing about that, is voltages have remained pretty constant over the past few days, from cold-start to redline, voltage has never gone over 14.6VDC - noticed 14.6 a little after I started 'er up this morning.

Just to clarify, before I go in and sound silly, AGM use electrolyte, not gel, right? The lady yesterday was so adamant yesterday that they were gel- she emphasized "gel" every time she was explaining how impossible it was for these batteries to leak - that I backed off.
 
there may be exceptions, but to my knowledge you are correct. AGM uses a standard electrolyte, and it's soaked into the matte. Here's the thing tho--- there's not an inch of it floating over the plates like a flooded cell, either, so AGM doesn't have that much liquid in it that's available to boil off in the first place.

Gel is just a thick electrolyte without the matte to absorb it.

I have never seen an AGM vent. Relief pressure is prolly ~6psi.

More likely you have a weak cell, and it's being overcharged, causing it to boil over.... but even that would be very strange for any battery of this age, and would be detectable by electronic test.... run headlamps for 15 minutes then measure... I'd expect 12.3-4 or so?

Might try a different sears and just say your new battery is leaking acid. don't clean it... just let it corrode, go back in a month to someone who you haven't had an argument with-- or call a 1-800 line...

M
 
I don't know if this pertains to AGM batteries or gel batteries, but if you overtighten the hold down clamp, you can distort the battery case to the point of the seals on the posts breaking and letting out fluid/gases.

Been there, done that.
 
Originally Posted By: meep
there may be exceptions, but to my knowledge you are correct. AGM uses a standard electrolyte, and it's soaked into the matte. Here's the thing tho--- there's not an inch of it floating over the plates like a flooded cell, either, so AGM doesn't have that much liquid in it that's available to boil off in the first place.

Gel is just a thick electrolyte without the matte to absorb it.

I have never seen an AGM vent. Relief pressure is prolly ~6psi.

More likely you have a weak cell, and it's being overcharged, causing it to boil over.... but even that would be very strange for any battery of this age, and would be detectable by electronic test.... run headlamps for 15 minutes then measure... I'd expect 12.3-4 or so?

Might try a different sears and just say your new battery is leaking acid. don't clean it... just let it corrode, go back in a month to someone who you haven't had an argument with-- or call a 1-800 line...

M



Solid advice. I plan to drive over there tomorrow after work to see what they say. I'll leave the corrosion be until then. I'll also run the headlights for a bit tonight and check the voltage - I'll post up the results.

Originally Posted By: Drew99GT
I don't know if this pertains to AGM batteries or gel batteries, but if you overtighten the hold down clamp, you can distort the battery case to the point of the seals on the posts breaking and letting out fluid/gases.

Been there, done that.


It was loose and required tightening at my last auto-x tech inspection, but I don't remember tightening down more than snug. I'll check that in a few and report back.
 
Sears is very good about honoring warranties. Like the other poster mentioned, drive over and speak to the manager, make sure to show them what you have found. My guess is that they will give you a new one.

I have to agree that it does look like out gassing from SOMEWHERE on the battery for those corrosion points to have occured.
 
Originally Posted By: urchin
Sears is very good about honoring warranties. Like the other poster mentioned, drive over and speak to the manager, make sure to show them what you have found. My guess is that they will give you a new one.

I have to agree that it does look like out gassing from SOMEWHERE on the battery for those corrosion points to have occured.


You're right, they were! One look at the corrosion and the red from the acid indicator and Eric, the "battery guru" at Waterford Sears immediately agreed to replace the battery under warranty.
banana2.gif


The battery was dated 9/10, which would normally turn me off from a LA battery, but I guess it doesn't matter so much on an AGM battery. Sears also places a stick on each battery after testing it at the 9 and 18 months mark. My new battery was checked last money, I guess.

I checked the voltage after driving 4 miles home and letting the car sit for an hour and the voltage read 12.86. I was thinking about putting it on the trickle charger over night, but I don't think it's necessary.
 
I've got 3 years, 3 months left on my free-replacement warranty, so even if it doesn't
smile.gif


I hope it's not an issue with the charging system that hasn't popped up in the past few days of logging voltages. :knocks on wood:
 
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