Hi people this is my first post on this forum, I'm hoping for some better insight into my issue since the specifics of my problem are nowhere to be found online or in battery manuals.
I recently bought two deep cycle flooded 12v 260ah batteries for my 24v system four months ago. When under moderate use I noticed the voltage would deplete very quickly to under 23v while the SG readings were over 1.260 in each cell. During the weeks I was scratching my head as to why this was happening and it was driving me insane until I ordered 2 proper glass hydrometers [1.100 - 1.300] since I was unsure of the plastic hydrometer I was using. After they new hydrometers arrived I tried and tested them and they were not giving any readings on these batteries, the complete float was resting under the water line, I thought I got ripped off so I ordered another glass one... The new one arrived and the same thing happened! Then the alarm bells rang in my head, I quickly went and tested all these hydrometers on a spare 12v car battery and discovered they all work perfectly and got a good 1.280 reading. The plastic hydrometer I was using was useless.
I am quite convinced that the shop I bought these batteries from were never put through a commission charge and we're sold with an SG close to 1.050, judging by the faulty hydrometer I had been using, and a time where I asked the salesman about hydrometers (he had no clue what they were or its use) let alone the absence of them in the shop. I assume that the employees filled the battery cells in a dry state with distilled water, charged the batteries for a few hours and thought it was good enough for customers...
Anyway, the batteries hit absorption phase (29.6v) for 3h nearly every day since I have had them so they had been getting a lot of charge. Another thing to note is that the cells look in great condition and do not have any visual signs of sulfation
My Goal now is to raise the SG to at least 1.260. So about 5 days ago I have been equilizing these batteries in series at 32v - 33v at 4 - 5 hour intervals with slow steady success. The total time spent on EQ is around 24 hours, the SG has risen and plateaued at 1.200 at 27° celsius from basically near nil acidity. The highest temp during these charges was 32° celsius. The bank is sitting at a very stable 24.4v now (SG 1.200) which I had never observed before the process was started.
The questions I would like to ask:
1# Should I stop the EQ charge and cycle the batteries for a day or two before I continue further equilizing, if the SG readings have plateaued for 2 hours during EQ?
2# Was sulfation even possible if the batteries never had an acid density anywhere near 1.100 in it's life?
3# Have you had experiences where you have had SG plateaus while equalizing before, and what is you advice on dealing with it?
4# If the batteries were cycled with such a low SG, do the cycles even count since I wasn't using the full capacity of the batteries?
5# Has the break in period even started after what has happened? I have heard that with wet lead acids they take around 90 cycles to achieve full working capacity.
Thanks for bearing with me,
Luke
Edit:
24v system 260ah, 2 x 12v batteries
After 24h of EQ charging at 32v - 33v the batteries are still accepting 22 amps but SG is stuck on 1.200
I recently bought two deep cycle flooded 12v 260ah batteries for my 24v system four months ago. When under moderate use I noticed the voltage would deplete very quickly to under 23v while the SG readings were over 1.260 in each cell. During the weeks I was scratching my head as to why this was happening and it was driving me insane until I ordered 2 proper glass hydrometers [1.100 - 1.300] since I was unsure of the plastic hydrometer I was using. After they new hydrometers arrived I tried and tested them and they were not giving any readings on these batteries, the complete float was resting under the water line, I thought I got ripped off so I ordered another glass one... The new one arrived and the same thing happened! Then the alarm bells rang in my head, I quickly went and tested all these hydrometers on a spare 12v car battery and discovered they all work perfectly and got a good 1.280 reading. The plastic hydrometer I was using was useless.
I am quite convinced that the shop I bought these batteries from were never put through a commission charge and we're sold with an SG close to 1.050, judging by the faulty hydrometer I had been using, and a time where I asked the salesman about hydrometers (he had no clue what they were or its use) let alone the absence of them in the shop. I assume that the employees filled the battery cells in a dry state with distilled water, charged the batteries for a few hours and thought it was good enough for customers...
Anyway, the batteries hit absorption phase (29.6v) for 3h nearly every day since I have had them so they had been getting a lot of charge. Another thing to note is that the cells look in great condition and do not have any visual signs of sulfation
My Goal now is to raise the SG to at least 1.260. So about 5 days ago I have been equilizing these batteries in series at 32v - 33v at 4 - 5 hour intervals with slow steady success. The total time spent on EQ is around 24 hours, the SG has risen and plateaued at 1.200 at 27° celsius from basically near nil acidity. The highest temp during these charges was 32° celsius. The bank is sitting at a very stable 24.4v now (SG 1.200) which I had never observed before the process was started.
The questions I would like to ask:
1# Should I stop the EQ charge and cycle the batteries for a day or two before I continue further equilizing, if the SG readings have plateaued for 2 hours during EQ?
2# Was sulfation even possible if the batteries never had an acid density anywhere near 1.100 in it's life?
3# Have you had experiences where you have had SG plateaus while equalizing before, and what is you advice on dealing with it?
4# If the batteries were cycled with such a low SG, do the cycles even count since I wasn't using the full capacity of the batteries?
5# Has the break in period even started after what has happened? I have heard that with wet lead acids they take around 90 cycles to achieve full working capacity.
Thanks for bearing with me,
Luke
Edit:
24v system 260ah, 2 x 12v batteries
After 24h of EQ charging at 32v - 33v the batteries are still accepting 22 amps but SG is stuck on 1.200
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