Hi Everyone,
Both my house and starter batteries are approx. 5 years old, have never been fully discharged and take a charge well.
Understanding that battery life has many variables, anything longer than ~5-6 years is pushing it.
How does one "inspect" a battery and assess its state?
Thanks
Frank
Assessing State Of Batteries
Moderator: Jim Walsh
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Frank Vernet
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- Location: Cape Dory 33 "Sirius" Hull #84 Deale, MD
Assessing State Of Batteries
"A sailor's joys are as simple as a child's." - Bernard Moitessier
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Steve Laume
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Great question, I am rather interested in myself.
Raven's house batteries are in that 5 to 6 year old range with a newer start battery. They are all AGMs and I would think you would need to add that information to your question to help define things.
Would type of chargers and regulators also have a bearing?
Thanks to anyone who has a better understanding of battery well being than I do, Steve.
Raven's house batteries are in that 5 to 6 year old range with a newer start battery. They are all AGMs and I would think you would need to add that information to your question to help define things.
Would type of chargers and regulators also have a bearing?
Thanks to anyone who has a better understanding of battery well being than I do, Steve.
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Ray Garcia
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- Joined: Apr 27th, '05, 22:08
- Location: 1981 CD27 #212 "Spirit" Huntington, NY
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My first inclination would be the battery no longer holds a charge. Especially after charging for an extended amount of time and 1 bulb drains it again quickly.
My car battery (ca. 2003) is just about dead. An overnight charge only lasts a few days before needing another boost. I think I got pretty good service life out of that battery. Then again a set of jumper cables and the charger are always at hand. I don't think I would wait that long to replace the boat batteries. Kinda hard to jump start a sailboat with cables.
On a boat when would you know? Probably when it's blowing real hard at night and your trying to make your way back to port. Doesn't it always happen when you need it the most?
My car battery (ca. 2003) is just about dead. An overnight charge only lasts a few days before needing another boost. I think I got pretty good service life out of that battery. Then again a set of jumper cables and the charger are always at hand. I don't think I would wait that long to replace the boat batteries. Kinda hard to jump start a sailboat with cables.
On a boat when would you know? Probably when it's blowing real hard at night and your trying to make your way back to port. Doesn't it always happen when you need it the most?
Battery University
The author of this article at Battery University suggests using 'capacity' as the measure. This is defined as how many amp-hours the battery can deliver over a certain period.
The trouble is there's no way to measure this capacity instantly, and most of us wouldn't set up a way to measure discharge over the standard 20-hour period.
Something could be done, though, either aboard or at home in the winter. Charge the battery up full (14.4 volts), and then attach a known load. See how far the voltage drops after a certain amount of time, and that would give you a benchmark to track the battery against in the future?
The trouble is there's no way to measure this capacity instantly, and most of us wouldn't set up a way to measure discharge over the standard 20-hour period.
Something could be done, though, either aboard or at home in the winter. Charge the battery up full (14.4 volts), and then attach a known load. See how far the voltage drops after a certain amount of time, and that would give you a benchmark to track the battery against in the future?
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tartansailor
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State of Charge
With respect to lead - acid batteries, the "correct" way is with a hydrometer which can be found at any good auto parts store.
Ace hardware either has, or can order one for you.
For a down and dirty you may wish to consider this:
100% 12.73v = 1.265 sp. gr.
90% 12.62
80% 12.50 = 1.225
70% 12.37
60% 12.24
50% 12.10 = 1.190
30% 11.81 = 1.155
0% 11.51 = 1.120
Published values for deep cycle may vary slightly.
Dick
Ace hardware either has, or can order one for you.
For a down and dirty you may wish to consider this:
100% 12.73v = 1.265 sp. gr.
90% 12.62
80% 12.50 = 1.225
70% 12.37
60% 12.24
50% 12.10 = 1.190
30% 11.81 = 1.155
0% 11.51 = 1.120
Published values for deep cycle may vary slightly.
Dick