"Wear Out" Mechanisms For Flooded Lead-Acid Batteries?
- Thread starter Steve Sr.
- Start date
Yes, they disintegrate; and, they can dry out due to loss of water; and, bits of the plates can build up in the bottom & short out cells, and sulfates can build up/plate out on the plates as well. Or, you can have my Johnson Controls/Clarios issue, they can leak acid all over everything!
Over time even a perfectly charged and maintained battery will suffer from positive plate erosion until it fails. Another less common faiure mode is where sulphates from the electrolyte build up on the negative plates, especially when the battery is chronically under charged.
A even less common failure type is when dissolved lead replates itself to a plate and forms what are called dendrites. When these dendrites stick out far enough to touch the adjacent plate, it forms a connection and effectively shorts them out.
The last type of fault is internal physical damage where connections or plates crack or break due to vibration or mechanical stress.
A even less common failure type is when dissolved lead replates itself to a plate and forms what are called dendrites. When these dendrites stick out far enough to touch the adjacent plate, it forms a connection and effectively shorts them out.
The last type of fault is internal physical damage where connections or plates crack or break due to vibration or mechanical stress.
This plus it's been my experience that when the water gets low the battery is doomed.
That is exactly right. The idea that sulfation is the leading cause of battery failure is incorrect. We scrap a lead acid battery when it is below 80% of it's rated capacity. Know that quality manufacturers sandbag the numbers a bit, and a 44AH Concorde lead acid battery will produce well above 50AH when new.
But the FAA, says it's done at 80%. or 35AH.
By the 80% mark, the positive plates are a mess and have deteriorated.
While not a great picture, you get the idea.
Here is a video that shows the positive plate and how it's made in India...
JHZR2
Staff member
All of the above. Lots of info out there.
Is this a common occurrence with current production? Where do they leak from? Around the terminals? Case crack?
Is there any way to determine the primary mechanism based on battery characteristics / symptoms at failure? I am trying to get my head around how an EOL battery would be able to start the car (sufficient CCA) but have near zero capacity.
I can remember decades ago that the usual failure mode would be insufficient CCA to start the engine, usually when cold (winter). More recently I have also seen and experienced situations where it goes from starting to "click" from one start to the next.
The battery getting the relay to 'click', and no more, is just a more severe example of insufficient CCA.
Seriously, I want to condense the info in this thread onto a handy card so I have the vocabulary handy.
The neighbor's kid had a no-start condition the other day due to a "very failed" battery.
I gave 'em the voltage test limits and a post cleanliness rap.
They listened attentively as I showed them where the group size was on the label and advised them to look up the correct battery size rather than just buy a replacement using the group number on theirs as it could've been incorrect.
I had the entire family's attention. I would've given them more had I had it handy.
The Clarios (formerly Johnson Controls) batteries are historically notorious for seeping acid from the base of the terminals. If I remember correctly, it is typically worse on the positive (+) terminal. Applying grease/petroleum jelly helps, as well as using the treated felt gaskets. The current batteries still have the leakage issues.
Coorsion (positive plate hot weather)
Sulphation (blocks electrical flow)
Sedimental shorts through the separator
Sulphation (blocks electrical flow)
Sedimental shorts through the separator
It use to be Exide batteries did this.
f355spider
$50 Site Donor 2024
I wonder what the average life expectancy is for people in India working in this industry...and their families? No respirators, no gloves, or protective clothing. They go home with lead particles on their clothing, and in their hair and contaminate their homes, bedding, etc.
I suspect they suffer later in life. I also suspect they know better but do it anyway. The information is readily available.
Alang Ship Breaking Yard - Wikipedia
In developing nation there are a lot of low income people willing to trade late life health issue to survive now. I would imagine up till recently the US coal miners had similar trade offs to think about.
A Nov. 2023 scholarly article, that I haven't read yet.
www.researchgate.net
(PDF) Comprehensive Study of Failure Mechanisms of Field-Aged Automotive Lead Batteries
PDF | Modern vehicles have increasing safety requirements and a need for reliable low-voltage power supply in their on-board power supply systems.... | Find, read and cite all the research you need on ResearchGate
www.researchgate.net
Also have not yet read this 2021 article from the same authors. It explains each of the 5 failure modes in some detail.
www.researchgate.net
Vertical axis is Probability of Failure. Horizontal axis is Lifetime 0-4 years. BCI (Battery Council International) failure mode data is from 2015.
(PDF) Methodology for Determining Time-Dependent Lead Battery Failure Rates from Field Data
PDF | The safety requirements in vehicles continuously increase due to more automated functions using electronic components. Besides the reliability of... | Find, read and cite all the research you need on ResearchGate
www.researchgate.net
Vertical axis is Probability of Failure. Horizontal axis is Lifetime 0-4 years. BCI (Battery Council International) failure mode data is from 2015.
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Yes
Batteries are way more oversized now compared to starter motor needs. These little gear reduction starter motors draw far fewer peak amps than the old direct drive ones. So a battery degrading still starts the engine even if it's near death's door, and sounds good doing it.
