I see a pattern/trend as to adding the acs sulfuric.
When I first started to work with these batterys, they were boiled out. So I used distilled water, to top off all the cells in each battery.
I then charged the battery's and the SG readings were low. So at 14volts, for the batt, the SG readings were low...
By adding ACS/REAGENT Sulfuric acid in 2ml quantitys at a time, to a given cell in a battery, once charged to 14 volts, it has been determined to increase re-charge time, after discharge cycle, in the following cycle, which is good.
In otherwords, Once I had a battery fully charged, I can add sulfuric, then discharge, to a given voltage, and the time for re-charge would be extended by the adjustment to the electrolite.
Im using a slow-charge method, so im not using a battery charger or pulse charger. Its a 'wallwort', wall transformer type. Rated at 12vdc 700ma class 2 transformer. Open circuit voltage is 17volts.
Anyhow, I get too this point, that I cannot charge the battery's anymore with it at 14vdc, they start to boil over. I take an SG reading, add sulfuric, then discharge, it takes longer to re-charge than before. So, I have been pretty impressed by the increase in charging rates. Battery discharge performace/capacity in amp-hours, has reflected this...
As I said before, it will take sometime to make a conclusion. But anyone can see what im getting at.
At first, I was worried that I would render the original electrolite useless, Fix the plates somehow, then have to re-fill with standard electrolite, dumping the old electrolite, to get a useable battery.
But now I see, that I can add distilled water and sulfuric ACS, to the original electrolite and get things working, without flushing any electrolite from the project battery's. But the battery's have to be in good shape, with regards to a visual inspection of the plates in each cell.
Providing that the batt's are not in hopeless shape, with regards to the mat inbetween the plates. I have seen many batt's that I would not even try this on, since the mat is pushed out or comprimised inbetween the plates.
These (agm) batt's are in really good shape. So its worth it, to try this.
JW