Battery Voltage Discrepancies ??
Hello battery experts and fellow nerds :C
I have noticed small voltage differences between the three Odyssey PC2150 batteries that make up my "bank". This is after resting with zero load for 24 hours following a 14.7V charge (in parallel) to 100% SOC (charge rate dropped to .001C).
The battery voltages were: a) 12.88V b) 12.92V and c) 12.96V. All measured within seconds of one another with the same calibrated digital volt meter.
All of the batteries are the same temperature (~70ºF), same age (mfr'd in Aug 2010), and have the same use/abuse history. Wiring is 2/0 throughout and is closely balanced. The three batteries are almost always charged/discharged together in parallel (not individually or in pairs). When tested separately, I have not been able to measure any other differences in any one battery's performance compared with the other two (ie. all three batteries appear to have similar capacity & voltage sag under load). Unfortunately, I never observed/noted the voltages when they were new.
So my questions are: What is the cause of this voltage difference? Is this a "normal" production tolerance? Is it caused by variations in specific gravity during production or from aging? Is it indicative of the batteries' "health"? Should I continue observe this over time or just ignore it?
I'm definitely not concerned about the voltage differences... I don't plan to change or replace anything in the electrical system, and if a problem ever arose I can isolate any one (or two) with the flip of a switch. Mostly I just want to better understand what's going on electro-chemically.
Thoughts?
Thanx in advance (for humoring me),
-Mark
I have noticed small voltage differences between the three Odyssey PC2150 batteries that make up my "bank". This is after resting with zero load for 24 hours following a 14.7V charge (in parallel) to 100% SOC (charge rate dropped to .001C).
The battery voltages were: a) 12.88V b) 12.92V and c) 12.96V. All measured within seconds of one another with the same calibrated digital volt meter.
All of the batteries are the same temperature (~70ºF), same age (mfr'd in Aug 2010), and have the same use/abuse history. Wiring is 2/0 throughout and is closely balanced. The three batteries are almost always charged/discharged together in parallel (not individually or in pairs). When tested separately, I have not been able to measure any other differences in any one battery's performance compared with the other two (ie. all three batteries appear to have similar capacity & voltage sag under load). Unfortunately, I never observed/noted the voltages when they were new.
So my questions are: What is the cause of this voltage difference? Is this a "normal" production tolerance? Is it caused by variations in specific gravity during production or from aging? Is it indicative of the batteries' "health"? Should I continue observe this over time or just ignore it?
I'm definitely not concerned about the voltage differences... I don't plan to change or replace anything in the electrical system, and if a problem ever arose I can isolate any one (or two) with the flip of a switch. Mostly I just want to better understand what's going on electro-chemically.
Thoughts?
Thanx in advance (for humoring me),
-Mark
