Forum Discussion
landyacht318
Dec 21, 2017Explorer
Many flooded batteries ago, I was rather insistent I did not need a hydrometer, as I had a shunted battery monitor. My discharges were not deep and my battery monitor kept telling me that all was well.
But for the AH removed from full, the voltage was dipping lower and lower all too soon.
Finally, I got the screwy 31, which I thought was the best 12v marine battery I could get my hands on. After 3 weeks of cycles this battery too, was dropping to 12.2v under light loads with nowhere near 65Ah of its 130 depleted, and I was seriously irritated. 130AH of capacity was seriously showing 12.2v under a 2.3 amp load with 21Ah removed from it, on a 3 week old battery getting 2 hours of 14.4v a day and floating at 13.1 the rest of the day with 25 to 35Ah removed from it daily.
So I finally get a temp compensated hydrometer( OTC 4619) let my solar controller goto blinking all is well mode, dip the cells and find them all at 1.220 or less Deep in the red! But but but my solar controller was flashing that green light and saying 0 AH from full every day well before sundown!!
My Only plug in charger at that time was an automatic schumacher, and this crazy charger will decide on its own, for whatever unfathomable resasonable reason, to sometimes go as high as 16.4 volts. I got it to go up there and it took something like 5 hours before Specific gravity crossed the 1.270 threshold on this three week old battery with 20 cycled on it to ~75% state of charge!!
The inability to really control the schumacher had me EQing the battery via my solar controller, setting absorption and float eventually as high as 16 volts for the regularly required EQ charges, and Specific gravity proved to max out at 1.285, but of course I had to prevent overnight discharge so the solar had enough sun and time to do this. It was a pain in the keester.
But I leanred what this battery required. The screwy31 still lives, though it was removed from deep cycle duty in my Rig in June 2015 and has seen mostly very light cycles since powering leds and fans and taking some load off of the 15 amp circuit feeding my workshop when I approached that limit using power tools.
I got about 535 deep cycles from the screwy 31 before I removed it from service in my rig and moved it to workshop floor. It likely has several hundred more shallow cycles on it since, primarily fed by the schizo Schumacher which comes on automatically when it gets 115vac and will shoot upto as high as 16.4v at the 2 amp setting.
About 2 weeks ago, the terminals were growing green and white corrosion badly through the grease and the lid was wet yet covered in cedr dust, weird things began happening to lights and fans, and 24 hours after removal from a charger it was still reading well over 13 volts. I decided it was time for the baking soda treatment with a toothbrush to all corrosion. I found each cell had plates exposed about 1/4 inch as exposed on most cells. I covered the cells and left the meanwell rsp-500-15 on it overnight at 14.7v, then in the morning cranked up voltage in a few stages, keeping about 5 amps flowing into the battery until it reached 16.2v.
Then I dusted off my hydrometer, and while there was barely enough electrolyte to fill the chamber and make the float float, all cells were in the green compensated for temperature. Then I filled the battery full with filtered drinking water, as I was not driving to store, just for distilled water, and dipped again and could not even get the float, to float. No surprise.
I let the meanwell pump ~18 more AH into it over ~12 hours or so at 14.4v, and got readings of ~1.220 on all cells.
I twisted voltage upwards to get 5 amps, in stages, until 16v was reached and left it there for a bit, then returned the meanwell to my rig. I Did not bother checking specific gravity again, but I bet I could, if babysitting it, get SG upto 1.275 plus on 5 of the 6 cells.
Many years ago I had 2 flooded 27s in parallel as dedicated house batteries, obviously sulfated. My friend had a battery minder 12248. I removed one battery and left it on the Minder for a week, then did the same to the other battery and put them back in parallel.
There was no improvement in voltage held for AH removed. Magically dissolve hardened sulfation? my keester.
My experience is the batteryminder pulse 'desulfating' charger was able to fully charge the sulfated battery, but it was not able to magically restore lost capacity on sulfated, chronically undercharged marine batteries, whose cycles were not all that deep. I was getting about 300 to 400 cycles to no less than 75% state of charge before performance was dismal and I deemed replacement of the pair of marine 27's, was necessary.
The screwy31 proved to me that full charge requires a hydrometer and much longer absorption charge durations, higher absorption voltages, and more frequent equalizations when deep cycled nightly.
My current Northstar AGM-27 proves to me that TPPL AGM batteries love high amp recharges, and to be held at absorption voltage until amps taper to 0.5% of capacity.
I have over 700 Deep cycles, over 4 years on this AGM. It is my ONLY battery, for house and engine and has been since I removed the screwy31 from my rig in june of 2015. While I can tell performance is not what it was when new, it still has absolutely no problems starting my engine depleted 65 amp hours of however many remain of the original 90 it was rated at, but granted it is not a cold environment.
I attribute the rather impressive lifespan and performance of this battery to high amp recharges, regular recharges to full almost every cycle, and I attribute this ability to achieve true full, to my modified MEanwell rsp-500-15, and also to my modified transpo540HD external adjustable voltage regulator controllng my alternator, and to my adjustable voltage MPPT solar controller.
The Key words are adjustable voltage. Knowing how long to achieve and then hold that voltage requires an Ammeter, on my AGM, and anyone who wnts good or better longevity from hard working regularly deep cycled floded batteries would be wise to have the ability to attain a true full, either by the 15v top charge, or the 16v equalization and of course the hydrometer to say when it is actually full.
Believing any magically marketed automatic charger is going to restore a sulfated battery, is simply hope and faith and the human desire to pat themselves on teh back for their expenditure of money on such a product claiming it can defy physics and logic and wanting really badly, to believe it.
I get that people do not want to babysit a battery, twisting dials watching voltmeters and ammeters or dipping hydrometers, but returning a battery in an unknown condition, other than it is degraded, to maximum remaining capacity, pretty much requires it.
Get a hydrometer, and an Ammeter, and a charging source which can get a battery upto 16v for as long as is wanted, by the human observing it. I've not done mex's current limiting light bulb, but I do twist voltage upwards in stages to keep about 5% of capacity flowing into the battery, and I will hold 16 to 16.2v as long as required to get specific gravity to max out or stop rising, and the screwy 31, still lives.
The other strategy is simply replace batteries more often. that could be a lot easier, and many people can afford to simply throw money at any problem. Not everybody has that option, but I would not buy any magically marketed desulfator thinking that it would do oanything more than a non pulse charger would, holding the battery at the same voltages.
Mex is largely responsible for my Adjustable voltage mindset and my ubndersstanding of what it takes to actually achieve a fully charged battery and thus good battery longevity, and I am achieving very good to excellent battery longevity, and have supreme confidence I can continue to do so, as I have the knowledge, mindset, and the tools that can do so, and none of them has the word automatic anywhere on it
And All my neighbors/friends know to bring me their batteries when they think it is time for a new one, or they needed a jumpstart. The meanwell with the Ammeter and AH/WH counter attached has kept almost every battery brought to me in service, even well beyond my expectations. I think this expectation exceeding, is more a tribute to how little capacity a battery needs to start a fuel injected engine in a mild climate
I usually can stuff 12 to 15more AH into the batteries brought to me after their automatic chargers flashed the green light, on their 50 to 100AH SLI starter batteries.
An adjustable voltage power supply and an ammeter will prove time and again, automatic chargers stop well short of the endgoal, and I feel that expecting any automatic charging source pulse charger or otherwise, to be able to restore an abused sulfated starting, marine or deep cycle battery to its maximum remaining potential capacity, is unwise in the extreme, to put it kindly.
I'd rather not put it kindly, but, so it goes.
My Meanwell rsp-500-15 is modified with a 10 turn bourns Potentiometer, and extra ventilation and heatsinking, but it can choose any voltage from 13.12 to 19.23 volts, and can provide upto 40 amps and can do it all day long. It has thousands of hours on it floating my battery at 13.6 or so and several hundred at higher voltages. It was 127$ delivered, but the POt, fans and wattmeter added another $75.The extra heatsinks were a gift from a member here.
But it is the most capable 40 amp charger/converter/desulfator on the planet and has likely paid for itself in the batteries it has either restored to their maximum remaining potential capacity, and by allowing me the ability to keep my hard working AGM in top condition for as long as it has.
The ability to twist a voltage potentiometer and see how many amps flow into a battery at various levels of depletion is Extremely enlightening as to how a battery charges, and the condition of that battery.
But for the AH removed from full, the voltage was dipping lower and lower all too soon.
Finally, I got the screwy 31, which I thought was the best 12v marine battery I could get my hands on. After 3 weeks of cycles this battery too, was dropping to 12.2v under light loads with nowhere near 65Ah of its 130 depleted, and I was seriously irritated. 130AH of capacity was seriously showing 12.2v under a 2.3 amp load with 21Ah removed from it, on a 3 week old battery getting 2 hours of 14.4v a day and floating at 13.1 the rest of the day with 25 to 35Ah removed from it daily.
So I finally get a temp compensated hydrometer( OTC 4619) let my solar controller goto blinking all is well mode, dip the cells and find them all at 1.220 or less Deep in the red! But but but my solar controller was flashing that green light and saying 0 AH from full every day well before sundown!!
My Only plug in charger at that time was an automatic schumacher, and this crazy charger will decide on its own, for whatever unfathomable resasonable reason, to sometimes go as high as 16.4 volts. I got it to go up there and it took something like 5 hours before Specific gravity crossed the 1.270 threshold on this three week old battery with 20 cycled on it to ~75% state of charge!!
The inability to really control the schumacher had me EQing the battery via my solar controller, setting absorption and float eventually as high as 16 volts for the regularly required EQ charges, and Specific gravity proved to max out at 1.285, but of course I had to prevent overnight discharge so the solar had enough sun and time to do this. It was a pain in the keester.
But I leanred what this battery required. The screwy31 still lives, though it was removed from deep cycle duty in my Rig in June 2015 and has seen mostly very light cycles since powering leds and fans and taking some load off of the 15 amp circuit feeding my workshop when I approached that limit using power tools.
I got about 535 deep cycles from the screwy 31 before I removed it from service in my rig and moved it to workshop floor. It likely has several hundred more shallow cycles on it since, primarily fed by the schizo Schumacher which comes on automatically when it gets 115vac and will shoot upto as high as 16.4v at the 2 amp setting.
About 2 weeks ago, the terminals were growing green and white corrosion badly through the grease and the lid was wet yet covered in cedr dust, weird things began happening to lights and fans, and 24 hours after removal from a charger it was still reading well over 13 volts. I decided it was time for the baking soda treatment with a toothbrush to all corrosion. I found each cell had plates exposed about 1/4 inch as exposed on most cells. I covered the cells and left the meanwell rsp-500-15 on it overnight at 14.7v, then in the morning cranked up voltage in a few stages, keeping about 5 amps flowing into the battery until it reached 16.2v.
Then I dusted off my hydrometer, and while there was barely enough electrolyte to fill the chamber and make the float float, all cells were in the green compensated for temperature. Then I filled the battery full with filtered drinking water, as I was not driving to store, just for distilled water, and dipped again and could not even get the float, to float. No surprise.
I let the meanwell pump ~18 more AH into it over ~12 hours or so at 14.4v, and got readings of ~1.220 on all cells.
I twisted voltage upwards to get 5 amps, in stages, until 16v was reached and left it there for a bit, then returned the meanwell to my rig. I Did not bother checking specific gravity again, but I bet I could, if babysitting it, get SG upto 1.275 plus on 5 of the 6 cells.
Many years ago I had 2 flooded 27s in parallel as dedicated house batteries, obviously sulfated. My friend had a battery minder 12248. I removed one battery and left it on the Minder for a week, then did the same to the other battery and put them back in parallel.
There was no improvement in voltage held for AH removed. Magically dissolve hardened sulfation? my keester.
My experience is the batteryminder pulse 'desulfating' charger was able to fully charge the sulfated battery, but it was not able to magically restore lost capacity on sulfated, chronically undercharged marine batteries, whose cycles were not all that deep. I was getting about 300 to 400 cycles to no less than 75% state of charge before performance was dismal and I deemed replacement of the pair of marine 27's, was necessary.
The screwy31 proved to me that full charge requires a hydrometer and much longer absorption charge durations, higher absorption voltages, and more frequent equalizations when deep cycled nightly.
My current Northstar AGM-27 proves to me that TPPL AGM batteries love high amp recharges, and to be held at absorption voltage until amps taper to 0.5% of capacity.
I have over 700 Deep cycles, over 4 years on this AGM. It is my ONLY battery, for house and engine and has been since I removed the screwy31 from my rig in june of 2015. While I can tell performance is not what it was when new, it still has absolutely no problems starting my engine depleted 65 amp hours of however many remain of the original 90 it was rated at, but granted it is not a cold environment.
I attribute the rather impressive lifespan and performance of this battery to high amp recharges, regular recharges to full almost every cycle, and I attribute this ability to achieve true full, to my modified MEanwell rsp-500-15, and also to my modified transpo540HD external adjustable voltage regulator controllng my alternator, and to my adjustable voltage MPPT solar controller.
The Key words are adjustable voltage. Knowing how long to achieve and then hold that voltage requires an Ammeter, on my AGM, and anyone who wnts good or better longevity from hard working regularly deep cycled floded batteries would be wise to have the ability to attain a true full, either by the 15v top charge, or the 16v equalization and of course the hydrometer to say when it is actually full.
Believing any magically marketed automatic charger is going to restore a sulfated battery, is simply hope and faith and the human desire to pat themselves on teh back for their expenditure of money on such a product claiming it can defy physics and logic and wanting really badly, to believe it.
I get that people do not want to babysit a battery, twisting dials watching voltmeters and ammeters or dipping hydrometers, but returning a battery in an unknown condition, other than it is degraded, to maximum remaining capacity, pretty much requires it.
Get a hydrometer, and an Ammeter, and a charging source which can get a battery upto 16v for as long as is wanted, by the human observing it. I've not done mex's current limiting light bulb, but I do twist voltage upwards in stages to keep about 5% of capacity flowing into the battery, and I will hold 16 to 16.2v as long as required to get specific gravity to max out or stop rising, and the screwy 31, still lives.
The other strategy is simply replace batteries more often. that could be a lot easier, and many people can afford to simply throw money at any problem. Not everybody has that option, but I would not buy any magically marketed desulfator thinking that it would do oanything more than a non pulse charger would, holding the battery at the same voltages.
Mex is largely responsible for my Adjustable voltage mindset and my ubndersstanding of what it takes to actually achieve a fully charged battery and thus good battery longevity, and I am achieving very good to excellent battery longevity, and have supreme confidence I can continue to do so, as I have the knowledge, mindset, and the tools that can do so, and none of them has the word automatic anywhere on it
And All my neighbors/friends know to bring me their batteries when they think it is time for a new one, or they needed a jumpstart. The meanwell with the Ammeter and AH/WH counter attached has kept almost every battery brought to me in service, even well beyond my expectations. I think this expectation exceeding, is more a tribute to how little capacity a battery needs to start a fuel injected engine in a mild climate
I usually can stuff 12 to 15more AH into the batteries brought to me after their automatic chargers flashed the green light, on their 50 to 100AH SLI starter batteries.
An adjustable voltage power supply and an ammeter will prove time and again, automatic chargers stop well short of the endgoal, and I feel that expecting any automatic charging source pulse charger or otherwise, to be able to restore an abused sulfated starting, marine or deep cycle battery to its maximum remaining potential capacity, is unwise in the extreme, to put it kindly.
I'd rather not put it kindly, but, so it goes.
My Meanwell rsp-500-15 is modified with a 10 turn bourns Potentiometer, and extra ventilation and heatsinking, but it can choose any voltage from 13.12 to 19.23 volts, and can provide upto 40 amps and can do it all day long. It has thousands of hours on it floating my battery at 13.6 or so and several hundred at higher voltages. It was 127$ delivered, but the POt, fans and wattmeter added another $75.The extra heatsinks were a gift from a member here.
But it is the most capable 40 amp charger/converter/desulfator on the planet and has likely paid for itself in the batteries it has either restored to their maximum remaining potential capacity, and by allowing me the ability to keep my hard working AGM in top condition for as long as it has.
The ability to twist a voltage potentiometer and see how many amps flow into a battery at various levels of depletion is Extremely enlightening as to how a battery charges, and the condition of that battery.
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