Input on AGM batteries

[jerichorick]

Originally Posted by az bound

(Dont mind the caps. I'm not yelling, its just for emphasis)
AGM batteries do NOT require a special charger
However,LIKE ANY OTHER BATTERY, they will benefit from the ministrations of a quality "smart" charger.
A reqular ol' conatant charger, such as sold at auto parts stores, feeds out power at around 12.7v (some are 12.6, and some are 12,8), thats it. Current flows through the battery until the battery gets to whatever voltage the charger is putting out, and then the voltage is equal on both ends of the wire and no power flows.
The problem with that, is at 12.7v the battery is no ttotally, completely, "full to the brim". More like 90% full. Close enough for governmeny work, but not as god as it can be.
Why does it matter??
All lead-acid batteries have this problem called "sulfation". Over time, sulfur crystals attach themselves to the lead plates and harden up. This reduces the overall area exposed to the electrolyte, and thus reduces the overall area of lead exposed to the electrolyte, reducing the overall capacity of the battery. Take a 100ah battery,and get a few spots of sulfur crystals here and there, and now its a 99ah battery. Repeat enough times and eventually, that 100ah battery might only be a 50ah battery. It still works fine, but for only 1/2 the time it did when new.
And of course, if there is enough buildup to deform the plates to where they actually touch..well, thats that. The battery is internally shorted and ready for the recycle bin.
Sulfation ALWAYS happens-its just the nature of the lead-acid beast-but certain conditions can allow it to happen faster. Leaving a battery sitting around at less than full charge is one of them. Draining it to far i.e., taking a cranking battery below 80% full, or a deep cycle below 50% full) is another.
Sulfation can happen pretty damned fast. Take a battery down 50% and leave it there even a couple of days, and there can be enough sulfation to have a measurable effect. Of course to actually measure it, you have to go through the hassleof doing a full capacity test,which is generally only something lab rats are goingto do.
So the absolute best thing to do to slow sulfation and extend the useful life, is to return that battery to fully charged "to the brim" every time, and of course never dran it down too far.
People often confuse AGM and GEL.
Lead-acid batteries that have the electrolyte absorbed into a fiberglass mat (AGM) take generallt the same charge voltages and charging schemes as regular ol' sloshy flooded (FLA) battery.
HOWEVER- batteries which have the electrolyte gelled with an additive usually DO require a special charger, because (A) require a bit lower charge voltage, and (B) are much more sensitive to overcharging than FLA or AGM.

Most of this article I agree with. But I am not in agreement with "AGM batteries do NOT require a special charger" because this is false if you want full life out of the batteries. Three stage charging at the correct voltages is the only way to do this. As I have already stated, I cooked a AGM bank when my charger went bad and put too much voltage on the string for too long a period of time.

We had special charger systems, when I worked in the power department of the phone company, for our hundreds of GEL CELL batteries. We monitored the voltages on a regular basis and often pulled a bad pack out of the string to return under warranty. AGM's are more forgiving but not to over voltage.

I think the manufacturer speaks better on this topic than any of us can: Lifeline Batteries - Marine & RV Deep Cycle Batteries

[Smitty77]

Originally Posted by dons2346

Smitty did you go to the factory? If so, did they install the batteries for you?

I am thinking about replacement but at 162 pounds each. I don't have the means to change them out myself/

I went thru Tom, and he arranged to have me pick these up in Azusa, CA. I believe this is the main distribution warehouse for Lifeline in this area. As I recall, Concorde Batteries out of West Covina, CA is the manufacturer for Lifeline. (Tom has helped many in the RV world, and I found him while accessing the Yahoo Country Coach User Group. He's a straight shooter, and provided good input that helped me in my decision process. I was thinking of a Lifeline AGM Starter 8D battery, but after reviewing Pro and Con with Tom, I went with the CAT Maintenance Free battery instead.)

Tom
Trans-Specialist - Your Source for Lifeline Batteries
770-634-7530

I did not install them myself, but from helping unload them out of my truck - I can confirm they have some weight!. I no longer recommend the shop that helped me with this install. But I can enthusiastically recommend Temecula Valley RV. They've helped me with my Magnum swap out to the MS2812 series (Missed the hybrid model by 6 months, and would have liked that!!), and did a great job on my Solar Panel system. (I sourced the parts I wanted, and arranged to have the major components dropped shipped to Temecula Valley RV. They sourced other parts for me to complete the full system.) It was a great experience on the full process, with professional and attention to detail that pleased me. And yes, they do have Shop Rates that reflect the costs of doing business in Southern California!

Best to you, and all,
Greg

[Sky_Boss]

Originally Posted by dons2346

Smitty did you go to the factory? If so, did they install the batteries for you?

I am thinking about replacement but at 162 pounds each. I don't have the means to change them out myself/

If you use 6V batteries the heaviest Lifeline Battery is 119#. I still think this is one of the reasons folks stick with 6V batteries.

The largest LL 12V AGM is 156# with 255 AH @ 12V
2 GPL-4CT 6V AGMs equal 66# each with 220 AH @ 12V
2 GPL-6CT 6V AGMs equal 90# each with 300 AH @ 12V

Now...certainly battery bay dimensions will dictate the most optimal sizing but as you allude to, the weight of handling them is certainly a factor. BTW...I don't think this is singularly an AGM vs wet cell battery factor. I assume wet cell batteries carry similar weight numbers when picking between 12V and 6V options.

[Sky_Boss]

Originally Posted by jerichorick

Most of this article I agree with. But I am not in agreement with "AGM batteries do NOT require a special charger" because this is false if you want full life out of the batteries. Three stage charging at the correct voltages is the only way to do this. As I have already stated, I cooked a AGM bank when my charger went bad and put too much voltage on the string for too long a period of time....

Let's make sure we aren't arguing semantics.

1. I think we are nearly all in agreement that ANY battery will perform better and last longer with a good 3 stage charger.

2. I think that the a "special" charger is one that has enough programing/profiles to meet the specific needs for battery types. i.e. My MS-2812 has a charging profile specific to both Lifeline AGM and non-Lifeline AGM (along with non-AGM) batteries.

If option 2 is "special" then I agree that AGMs are best served by a special charger.

[az bound]

Originally Posted by jerichorick

Most of this article I agree with. But I am not in agreement with "AGM batteries do NOT require a special charger" because this is false if you want full life out of the batteries. Three stage charging at the correct voltages is the only way to do this. As I have already stated, I cooked a AGM bank when my charger went bad and put too much voltage on the string for too long a period of time.

We had special charger systems, when I worked in the power department of the phone company, for our hundreds of GEL CELL batteries. We monitored the voltages on a regular basis and often pulled a bad pack out of the string to return under warranty. AGM's are more forgiving but not to over voltage.

I think the manufacturer speaks better on this topic than any of us can: Lifeline Batteries - Marine & RV Deep Cycle Batteries

Did you miss this statement ?
However , like any other battery, they will benefit from the ministration of a quality "smart" charger.

[TQ60]

Smart or special chargers are NOT needed but it does make a difference.

We have had to maintain hundreds of small dc plants and all require a human to maintain them.

Mainly keeping track of voltage and connectors.

[ladagobago]

I made a mistake the other day when I wrote the wrong Model number for my Optima
AGM.
These batteries have seen service for many year and nearly indestructible.
I use two of them to instantly start my ISB. They will take a high voltage charge up to 15 volt.
I don't know that I would use them for house batteries but they are damn sure great for starting any large motors. They sit for long period with no loss of power even when coated with road dust. My Alternator typically will be showing about 14.6 volts charge when running down the road.

Product ID: SC31DM
Cranking Amps: 1125
Cold Cranking Amps: 900
Voltage: 12
Termination: Common Code M
Width: 6.5
Length: 12.81
Height: 9.38
ReserveCapacity-25: 155.0

So there you have it. read and believe.
As for the heart inverter charger. I used them in my boat for over 16 years. They worked ok but they always over charge and gas the LA wet batteries. Never would use them on the agm.

I still prefer the flooded batteries = 6 volt GC for house battery. notice there are no extra patch cables. I made buss bars out of aluminum stock and wrapped with tape to insulate in the event of a dropped tool etc. at less than $100 each they offer the best balance of bucks for battery or dollars for amp hours.

[az bound]

Originally Posted by ladagobago

I made a mistake the other day when I wrote the wrong Model number for my Optima
AGM.
These batteries have seen service for many year and nearly indestructible.
I use two of them to instantly start my ISB. They will take a high voltage charge up to 15 volt.
I don't know that I would use them for house batteries but they are damn sure great for starting any large motors. They sit for long period with no loss of power even when coated with road dust. My Alternator typically will be showing about 14.6 volts charge when running down the road.

Product ID: SC31DM
Cranking Amps: 1125
Cold Cranking Amps: 900
Voltage: 12
Termination: Common Code M
Width: 6.5
Length: 12.81
Height: 9.38
ReserveCapacity-25: 155.0

So there you have it. read and believe.
As for the heart inverter charger. I used them in my boat for over 16 years. They worked ok but they always over charge and gas the LA wet batteries. Never would use them on the agm.

I still prefer the flooded batteries = 6 volt GC for house battery. notice there are no extra patch cables. I made buss bars out of aluminum stock and wrapped with tape to insulate in the event of a dropped tool etc. at less than $100 each they offer the best balance of bucks for battery or dollars for amp hours.

The Optima SC31DM is also a hybrid battery. Deep cycle/ starting, hense the CCA rating.

[MRUSA14]

Here is my experience. I bought a new Beaver coach in 2003 which came with Interstate flooded cell batteries. Under normal use, those batteries' capacity had shrink by 2006 to about half of their original capacity. It was at the point where I could hardly make it through the night without going below 50% SOC, and the Auto Gen Start was starting more and more frequently, so I bit the bullet and installed Lifeline AGMs. I continued to use the original equipment Xantrex charger which had a setting in it for AGM's. I used those batteries in the identical usage pattern that I did the original flooded cell batteries.

In 2013 I traded this coach for a new one. At that time the Lifelines were still providing like new performance. Based on this, it is AGMs for me in the future based on the longevity of the batteries, and the other benefits which have already been detailed in this thread.

I realize that some people will not feel comfortable with the added expense of AGMs and that is perfectly okay. It is a personal decision and there is no right or wrong. However speaking personally I say this: When I fly in a plane I always sit in a coach seat, because first class is too expensive, but when I buy batteries, I personally prefer to go first class.

[jerichorick]

No, I didn't miss the lifeline link. But to keep this discussion pure we must all agree that AGM's come in two flavors for our purpose. (This is mentioned above.) There is the start/deep cycle hybrid design (Optama... great company) and the true deep cycle AGM such as LifeLine. My NAPA are made by Optama I found out while participating in this discussion. Simply by design this type of battery can take the high voltage of 15V and survive. LifeLine can not by design.

I guess we can see it this way from what all of us have contributed. The manufacturing spec of the battery needs to match our charger. This really simplifies the matter. Choose a AGM battery that fits the charger capabilities and you are golden.

There is another misconception that we are all lead to believe because of the way the many manufactures word there product usage. "Marine use." When reading over the specs of different companies I discovered that not all AGM's are hybrid for marine use. Many are true "deep cycle". The physical design of the battery is what makes it suitable for marine usage. Can it take the physical abuse and continue to function as designed.

This has been a great discussion. I have learned much and it has caused me to dig deeper than I have in the past, building and correcting on the knowledge I have and miss-have.

I hope the OP has gained as I have.

Rick Y

[az bound]

Hopfully all interested are now aware from the discussion that there are the four different types of AGM batteries, with each having its intended purpose, independent of the other.

[TQ60]

The short answer to this 10 page thread is first to do plenty of investigation to determine what you have and what you need.

Factor in what you want then do proper homework to determine what must be done to get from where you are at to where you want to be.

That includes full review of all data sheets and confirmation of your engineering.

Skip any step and you will likely be not happy

[hes4all]

Originally Posted by TQ60

The short answer to this 10 page thread is first to do plenty of investigation to determine what you have and what you need.

Factor in what want then do proper homework to determine what must be done to get from where you are at to where you want to be.

That includes full review of all data sheets and confirmation of your engineering.

Skip any step and you will likely be not happy

TA-DA

[jerichorick]

Originally Posted by hes4all

TA-DA

X2