Nearly dead starter battery - what to expect?
I wrote briefly in another topic. 5 years old, left in a warm climate for 8 months with terminals disconnected. Upon return found it completely discharged, Voc=11.86. Multimeter "might" read lower tha...
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This is odd. Following the advice by SMK, I hooked up dying flooded starter to solar charger and 245W panel. Yes sir, AGM and flooded in parallel to one charger.
3 AGM before this were floating at 13.6V for 3 days and came down to <1A current.
Dying starter before this (when tried to charge separately) was sitting at permanent ABS stage for 2 days, 14.4V and current gradually dropping to 0.5A, and solar charger hated this battery and was switching back and forth between ABS and bulk mode. Rest overnight Voc (before today's experiment) was 12.45.
Didn't change Bulk-ABS 14.6V setpoint. Didn't change ABS-Float 13.6 V setpoint. Changed Float current setpoint to 1.5A (1+0.5=1.5).
In parallel, 3 good + 1 bad: as if bad one wasn't even there. Started with bulk, raised quickly to 14.6, transitioned to ABS, then dropped quickly to 13.6 Float setpoint, and went into Float. All 4 are peacefully floating now at 13.6. No erratic behavior of the charger (no switching ABS/Float every minute). The only minor difference is that current is now 1.5A, which makes sense as 3 good batts were at 1A and one bad - at 0.5A.
Will see what happens.
3 AGM before this were floating at 13.6V for 3 days and came down to <1A current.
Dying starter before this (when tried to charge separately) was sitting at permanent ABS stage for 2 days, 14.4V and current gradually dropping to 0.5A, and solar charger hated this battery and was switching back and forth between ABS and bulk mode. Rest overnight Voc (before today's experiment) was 12.45.
Didn't change Bulk-ABS 14.6V setpoint. Didn't change ABS-Float 13.6 V setpoint. Changed Float current setpoint to 1.5A (1+0.5=1.5).
In parallel, 3 good + 1 bad: as if bad one wasn't even there. Started with bulk, raised quickly to 14.6, transitioned to ABS, then dropped quickly to 13.6 Float setpoint, and went into Float. All 4 are peacefully floating now at 13.6. No erratic behavior of the charger (no switching ABS/Float every minute). The only minor difference is that current is now 1.5A, which makes sense as 3 good batts were at 1A and one bad - at 0.5A.
Will see what happens.
