HiTech
May 24, 2013Explorer
Positive Grid Corrosion
So getting ready to put some more float charge into the AGMs in prep for a 500w+ load test this weekend, I floated a little water over the valves. Battery was warm at 87 degrees. I have been waiting until they cool off to add BTUs. Sitting there...I heard...occasional bubbling? Open circuit?
So the only thing I know about so far that is supposed to be going on in a nearly charged battery is positive plate corrosion, that can act as a counter to self discharge in AGMs. So hmm how's that work.
Oh.
Lead plus water = electrons plus....hydrogen. Under no charge. Just sitting there oxidizing.
Floating in a very narrow temperature-corrected voltage range minimizes the corrosion. Letting the battery sit. Charging it. Floating it a few tenths off - they all radically accelerate positive grid corrosion.
In an AGM, seems like this would throw off the stoichiometeric ratio needed for the gasses to recombine into water internally.
Hmmmm. Have not found anything in the literature about THAT yet. So either I am way off, or I am searching on the wrong terms. Well there's always that 250 page (literally) PhD dissertation I have been meaning to read on how to properly determine float voltage...
Jim
So the only thing I know about so far that is supposed to be going on in a nearly charged battery is positive plate corrosion, that can act as a counter to self discharge in AGMs. So hmm how's that work.
Oh.
Lead plus water = electrons plus....hydrogen. Under no charge. Just sitting there oxidizing.
Floating in a very narrow temperature-corrected voltage range minimizes the corrosion. Letting the battery sit. Charging it. Floating it a few tenths off - they all radically accelerate positive grid corrosion.
In an AGM, seems like this would throw off the stoichiometeric ratio needed for the gasses to recombine into water internally.
Hmmmm. Have not found anything in the literature about THAT yet. So either I am way off, or I am searching on the wrong terms. Well there's always that 250 page (literally) PhD dissertation I have been meaning to read on how to properly determine float voltage...
Jim