"Solar AGM" vs plain AGM

[RoadtripsAndCampfires]

As if life isn't complicated enough.  Does this mean that if I want to buy 4 AGM batteries now and keep them charged via Honda Generator/battery charger that I can't later use these same batteries with my solar system down the road when I change over to that because they are not "solar AGM" batteries?

 

[tripper]

You can use them for both. Just ensure they are (true) deep cycle batteries unless you need to use them as starting batteries also, then get marine deep cycle.

 

[John61CT]

Batteries are classified by their discharge patterns, not how they get charged.

Deep cycling is what you need, and few AGMs are suitable for that.

Odyssey, Northstar or Lifeline in the NA market.

 

[John61CT]

Any quality deep cycling batt of sufficient size can also handle cranking duties with the back of their hand.

Inferior pseudo deep-cycle "dual use" batts that mention cranking are really just more-robust Starters, not suitable for extensive deep cycling.

Maybe occasional or light usage.

Only exceptions with AGM are the three vendors mentioned above.

 

[John61CT]

And only get AGM if you truly need something they offer.

Don't last as long as FLA, less robust, more finicky care requirements and of course more expensive.

 

[RoadtripsAndCampfires]

Thanks all. The batteries must go inside, thus AGM. They will go in a trailer so no starting bat capabilities needed. Deep-cycle is what I am talking about and.

 

[frater secessus]

The "solar" or "renewable energy" designation may mean nothing (ie, just marketing crapola) or something.

In the case of reputable manufacturers like Trojan, it means the internals are tweaked a little to make them more resilient in Partial State of Charge (PSOC) use. Trojan specifies 15% more cycles for their RE batteries that contain "smart carbon". Of course, if they cost more than 15% more maybe it's a non-issue for folks like us.

 

[RoadtripsAndCampfires]

Thanks Frater

 

[highdesertranger]

this is the first time I have even heard the term "Solar AGM". I would like to see an ad and read what makes it "solar". highdesertranger

 

[Exexpeditor]

It’s the same thing for both. Just a marketing gimmic.

 

[KathyC]

From Trojan's website

https://www.trojanbattery.com/solar-agm-2/

"[font=Arial, Helvetica, sans-serif]Trojan has incorporated several key engineering features in its Solar AGM batteries for renewable energy, hybrid and backup power applications that require deep-cycling power in a non-spillable battery design...."[/font]

 

[highdesertranger]

well I'll be, learn something new everyday. highdesertranger

 

[KathyC]

well I'll be,  learn something new everyday.  highdesertranger

And yet...this still sounds like marketing BS

 

[John61CT]

Trojan RE series definitely last much longer than their standard deep cycle lines.

But whether they are "better value" given the higher price, open to debate, ideally testing.

 

[Exexpeditor]

Interesting

 

[Ticklebellly]

I cannot, for one moment, imagine what engineering features would make a product more/most/better suitable for use when Solar is the charging energy source. I do notice the wishy-washy reference to RE, hybrid, and backup applications. WTF does that mean? I remain cynical in the perspective that the "S" is no more that a marketing gimmick and no more than click bait. Perfectly happy to accept this product line is made to a higher spec than other DC batteries in their product line but still see the "S" as an attempt to attract a specific demographic.

 

[Weight]

Trojan solar are shown with more cycles at 50% than their other AGM deep cycle.
But that is Trojan, the OP sounds like a better label and the label is the important part.

 

[frater secessus]

I cannot, for one moment, imagine what engineering features would make a product more/most/better suitable for use when Solar is the charging energy source.

Solar charging is relatively low-current and often PSOC.  This could increase hard sulfation.

In the case of the Trojan RE batteries I mentioned earlier, some of them have:

• more lead, with possibly less dense electrolyte for less corrosion
• carbon in the paste.  We have seen a similar thing done more extensively in the Firefly battery which is made specifically for PSOC scenarios
• taller case - it has not been confirmed (none cut open) but the working theory is there is a little extra space at the bottom to help prevent/delay shorting by sloughed sulfate.

I'm with John; they are confirmed to provide more cycles on average, but I do not know that the extra price is worth.  When I looked at it last time it was something like 25% more cost for 15% more cycles.  If they are hard to get to or if one is infirm then the extra life may be worth it.

Edited to add:
RE - renewable energy scenarios: psoc and deeply cycled between charging. No access to shore power.
Hybrid - dunno
backup - stationary UPS type applications. Floated, almost never cycled. These need to have stable electrolyte so it doesn't stratify and corrode the plates. This use case led to the development of AGM -- the electrolyte is held in place.

 

[John61CT]

From a company outside the dozen or so known good, I would not attach any value to a "Solar" label.

RE is a specific Trojan line, trustworthy company, but of course they do have a marketing dept.

____
Hybrid may be used to mean dual-use

Meaning a bit beefed up Starter batt, but not true deep cycling, like the Optima color tops.

 

[RoadtripsAndCampfires]

This is what I've decided to do. We won't get the solar for about a year from now as there are so many things to add to this blank trailer. So, we'll get one (1) AGM and put it inside to run the fridge just during travel, the rest of the time it'll be on propane unless we have hookups in which case it will be on electric. Later when we buy the 3 or 4 batteries (AGM probably but not the Trojan Solar) the battery we are going to use now can go in the back of the truck and we'll hook something to it or sell it.

I can't put the battery on the tongue as I need the weight under the axle instead and I want to designate the space anyway. It would be too tongue heavy otherwise I think due to what's where inside.

Sounds like a sound plan?