My Screwy 31
First off let me say I am not stressing over this. It's just a battery, it is only money, it is meeting my overnight needs, but it is displaying strange behavior, and I am curious as to why. So th...
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Battery has been cycled most every night since last report, recharged primarily through solar. Just checked SG on the 31 after Solar went into float of 14.7 after a few hours at 14.5v.
I could not get my plastic hydrometer to shake the bubbles off the float, so busted out the glass One.
1.235, 1.235, 1.230 on the 3 easy to access cells.
No bubbles stuck to glass float. Electrolyte clear. NO obvious water usage since the last time I pulled the cap.
I switched all loads to other battery and I put the solar acceptance and float upto 15.5v on the screwy31. It required 2.87 amps to nearly instantly bring it up to 15.5v measured at battery terminal 30 seconds after switching.
Last night I pulled 50 amp hours out of the 31. It had dipped as low as 11.8v under a 10 amp max load at that point. The load averaged about 6 to 7 amps until that point. Not sure what it rebounded to after switching all loads to the AGM.
In general my overnight usage has averaged 18 to 27 amp hours. I browse the internet on my Smartphone instead of the laptop now, saving a bunch of battery power, also the days are longer.
So the Screwy31 is still meeting my needs, easily, but the low SG and the lower than hoped for voltage, under load, is not reassuring but I will keep cycling it and updating here as it ages.
The Northstar AGM still impresses me, even though it mostly has just been the engine starting battery. Its ability to quickly crank the engine is impressive. It is nearly like an instant start at the turn of the key, even when the engine is overnight cold. If the engine is already warm, it is even quicker, almost scary fast.
Perhaps the "Pulse" cranking amps figure that Both Odyssey and Northstar like to include on their spec sheets is not just marketing doublespeak. I wonder how a flooded battery's "pulse" cranking amp figure would compare.
All I can say is that the engine cranks as fast or faster with the Northstar, than when I had 3 flooded group 27 marine fully charged batteries feeding the starter.
Edit. 30 minutes after bumping the voltage upto 15.5 SG rose to 1.255, 1.255 and 1.250 on the same cells. Cells bubbling fairly vigorously. battery aking 2.42 amps to hold 15.55v. Electrolyte still clear but "warbly" looking like looking over asphalt on a hot summer day.
Shadows are approaching solar panels.
I could not get my plastic hydrometer to shake the bubbles off the float, so busted out the glass One.
1.235, 1.235, 1.230 on the 3 easy to access cells.
No bubbles stuck to glass float. Electrolyte clear. NO obvious water usage since the last time I pulled the cap.
I switched all loads to other battery and I put the solar acceptance and float upto 15.5v on the screwy31. It required 2.87 amps to nearly instantly bring it up to 15.5v measured at battery terminal 30 seconds after switching.
Last night I pulled 50 amp hours out of the 31. It had dipped as low as 11.8v under a 10 amp max load at that point. The load averaged about 6 to 7 amps until that point. Not sure what it rebounded to after switching all loads to the AGM.
In general my overnight usage has averaged 18 to 27 amp hours. I browse the internet on my Smartphone instead of the laptop now, saving a bunch of battery power, also the days are longer.
So the Screwy31 is still meeting my needs, easily, but the low SG and the lower than hoped for voltage, under load, is not reassuring but I will keep cycling it and updating here as it ages.
The Northstar AGM still impresses me, even though it mostly has just been the engine starting battery. Its ability to quickly crank the engine is impressive. It is nearly like an instant start at the turn of the key, even when the engine is overnight cold. If the engine is already warm, it is even quicker, almost scary fast.
Perhaps the "Pulse" cranking amps figure that Both Odyssey and Northstar like to include on their spec sheets is not just marketing doublespeak. I wonder how a flooded battery's "pulse" cranking amp figure would compare.
All I can say is that the engine cranks as fast or faster with the Northstar, than when I had 3 flooded group 27 marine fully charged batteries feeding the starter.
Edit. 30 minutes after bumping the voltage upto 15.5 SG rose to 1.255, 1.255 and 1.250 on the same cells. Cells bubbling fairly vigorously. battery aking 2.42 amps to hold 15.55v. Electrolyte still clear but "warbly" looking like looking over asphalt on a hot summer day.
Shadows are approaching solar panels.
