Forum Discussion
wa8yxm
May 12, 2014Explorer III
If you are getting only 4 years going AGM is not going to help. You have a problem.. There are a few things that kill batteries fast.
First: My battery story:
Motor home purchased 2005 (May) Flooded wet cell house batteries and Maintenance Free Chassis battery (Chassis build date Aug 2004) I replaced the Chassis battery I think in December, House in Feburary (Last dec and Feb in both cases) Might as well say this year on both.
AGM's purchased in 2006 put on their own "Loop" (Isolated from flooded wet cells) with Xantrex Prosine 2.0 programmed for AGM.. As they aged I added a couple Group 29's I had that were OLDER than the Motor home.
AGM's replaced in 2011 (With maintence free),, One G-29 junked in 2012, Rest replaced in 2013.
IN short, the AGM's only lasted 5 years,, (Actually they should have been replaced earlier)
UNLESS you are doing a serious electrical upgrade there is no advantage to AGM over Maintenance free save the ability to disregard "This side up" stickers.
Now: your problem
The things that can kill Flooded wet cells include:
Lack of owner inspection and maintenance (letting them dry out), use of NON distilled water (Tap water contains minerals that damage the battery).
And all the things on the list of "Stuff that kills ALL lead acid (And in many cases other types) of battery:
Leaving them "Run down" for extended periods
Winter storage in a "Run Down" condition (Put a battery midner on 'em if you do not have a top rated converter like the Progressive Dynamics Intella power 9200).
Running them down too far too often (more on that in the next "page" (Section).
And finally,,, BAD CONVERTER.. The Magnetek 6300 line is noted for being very slow to recharge (A good thing) but not knowing when to stop (A very bad thing), and it's not the only one that does that. Some converters NEVER fully charge the battery,, Some never stop charging. I only rank the top and bottom ones by name.
Running them down too far:
DEEP CYCLE batteries (like the GC-2 Golf Car battery which is a flooded wet cell) are designed to survive routine discharge to as low as 50% SOC with the occasional "OH $#!t DEEPER discharge (like to the point where lights, won't) Mine were taken down to 10 volts or less at least half a dozen times over 10 years.
Starting batteries ... Well, I would suggest you not run them down that low they like to be near full (Say 80%)
Marine/Deep cycle, are primarily starting batteries,, Try to keep 'em 75 or better
The major differences between the types:
DEEP CYCLE is much more likely to recover from an OPPS level discharge.. But Starting batteries are better are really high discharge rates (Relative to their capacity)
So, how come your DEEP CYCLE house batteries can be used via the AUX/EMERGENCY Start/BOOST button to "Jump start" the engine?
Well, my Chassis battery is I think 78 amp hours, so a 150 amp load (Starter is typically less than that) is, slightly rounded 2x the 20 hour capacity of the battery.
But the house batteries (As delivered) 220 amp hours, So that same load is just over 70% of C/20 capacity.. That's why.. For the Big jars it's a much smaller load. Oh, new house batteries are bigger, 230 amp hour.. I could not lift them off the ground lying on my back (I could the old ones) they have to be lifted in. I did lift the chassis battery.
First: My battery story:
Motor home purchased 2005 (May) Flooded wet cell house batteries and Maintenance Free Chassis battery (Chassis build date Aug 2004) I replaced the Chassis battery I think in December, House in Feburary (Last dec and Feb in both cases) Might as well say this year on both.
AGM's purchased in 2006 put on their own "Loop" (Isolated from flooded wet cells) with Xantrex Prosine 2.0 programmed for AGM.. As they aged I added a couple Group 29's I had that were OLDER than the Motor home.
AGM's replaced in 2011 (With maintence free),, One G-29 junked in 2012, Rest replaced in 2013.
IN short, the AGM's only lasted 5 years,, (Actually they should have been replaced earlier)
UNLESS you are doing a serious electrical upgrade there is no advantage to AGM over Maintenance free save the ability to disregard "This side up" stickers.
Now: your problem
The things that can kill Flooded wet cells include:
Lack of owner inspection and maintenance (letting them dry out), use of NON distilled water (Tap water contains minerals that damage the battery).
And all the things on the list of "Stuff that kills ALL lead acid (And in many cases other types) of battery:
Leaving them "Run down" for extended periods
Winter storage in a "Run Down" condition (Put a battery midner on 'em if you do not have a top rated converter like the Progressive Dynamics Intella power 9200).
Running them down too far too often (more on that in the next "page" (Section).
And finally,,, BAD CONVERTER.. The Magnetek 6300 line is noted for being very slow to recharge (A good thing) but not knowing when to stop (A very bad thing), and it's not the only one that does that. Some converters NEVER fully charge the battery,, Some never stop charging. I only rank the top and bottom ones by name.
Running them down too far:
DEEP CYCLE batteries (like the GC-2 Golf Car battery which is a flooded wet cell) are designed to survive routine discharge to as low as 50% SOC with the occasional "OH $#!t DEEPER discharge (like to the point where lights, won't) Mine were taken down to 10 volts or less at least half a dozen times over 10 years.
Starting batteries ... Well, I would suggest you not run them down that low they like to be near full (Say 80%)
Marine/Deep cycle, are primarily starting batteries,, Try to keep 'em 75 or better
The major differences between the types:
DEEP CYCLE is much more likely to recover from an OPPS level discharge.. But Starting batteries are better are really high discharge rates (Relative to their capacity)
So, how come your DEEP CYCLE house batteries can be used via the AUX/EMERGENCY Start/BOOST button to "Jump start" the engine?
Well, my Chassis battery is I think 78 amp hours, so a 150 amp load (Starter is typically less than that) is, slightly rounded 2x the 20 hour capacity of the battery.
But the house batteries (As delivered) 220 amp hours, So that same load is just over 70% of C/20 capacity.. That's why.. For the Big jars it's a much smaller load. Oh, new house batteries are bigger, 230 amp hour.. I could not lift them off the ground lying on my back (I could the old ones) they have to be lifted in. I did lift the chassis battery.
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