12v vs series wired solar storage batteries

[weestrom05]

What would I gain or loose if I were to use 2 parallel wired 12 volt deep cycle batteries rather than 2 6 volt golf cart batteries. Planning on 2 100 watt renogy panels. Main load will be dometic cf refrig,  led lights,iPad and I phone charging. Also a small 12 v tv. No inverter at this time. Thanks

 

[highdesertranger]

true 12v deep cycle batteries are hard to find and expensive compared to 6v deep cycle batteries. that is the main reason people go with 6v wired in series. note, when a 12v battery says marine or starting/deep cycle, it's not a deep cycle battery. highdesertranger

 

[B and C]

I have two 12V AGM deep cycle batteries (5 year old telephone system batteries when I got them) that are still going strong over 3 years later. I am not full time though. This is 250 AH worth of battery. I usually only take about 15 to 20 percent out of them overnight. The 6V golf cart batteries are FLA (flooded lead acid) batteries meaning that you have to monitor and add distilled water when they get low. They can also off-gas if recharged fast.

So what you lose using two 12V AGM's is the monitoring and adding distilled water to the 6V FLA's. Different batteries have different AH capacity too.
FLA's if taken proper care of will probably last longer though.
Name you poison

 

[John61CT]

As HDR said, 12V that are true deep cycle are specialized, usually less robust and more expensive, whether flooded or AGM.

Can't really beat the value of 6V FLA Duracell GCs, as sold by Sam's Club and Batteries+. Trojan 105s are usually a bit pricier, Costco's def not as good.

 

[Canine]

Trogan claims, "Trojan’s Reliant™ Line of U.S.-made Absorbed Glass Mat (AGM) batteries are the only true deep-cycle AGM battery on the market today."

But Lifeline makes what they claim is a deep cycle 6 volt AGM and my understanding is they make one heck of a battery. Is Lifeline a good option for 6 volt AGM deep cycles?

 

[weestrom05]

With thi info I think I’ll use the Interstate golf cart units at Costco. Thanks for the info

 

[John61CT]

Trogan claims, "Trojan’s Reliant[emoji769] Line of U.S.-made Absorbed Glass Mat (AGM) batteries are the only true deep-cycle AGM battery on the market today."

But Lifeline makes what they claim is a deep cycle 6 volt AGM and my understanding is they make one heck of a battery. Is Lifeline a good option for 6 volt AGM deep cycles?

Yes one of the best. Odyssey also, and Northstar.

These are the only three mainstream AGM makers I'd recommend.

Rolls and Trojan make great flooded, but new to AGM, will take 5-7 more years to tell if good or not IMO.

Trojan's dishonest hyperbole cause me to trust them less and less as a company, but still recommend their FLA.

 

[John61CT]

Note with those three AGM makers, 12V is fine, they really mean deep cycle when ** they** say it.

But you pay accordingly, FLA is much better value per AH per year.

 

[John61CT]

With thi info I think I’ll use the Interstate golf cart units at Costco. Thanks for the info

Made by Johnson Controls, not nearly as good as the Deka/Duracell from Sam's or Batteries+.

I suppose if Costco's were 30% less then OK but I doubt it?

 

[Weight]

Duracell from Sam's Club if you are a member, otherwise Batteries plus Bulbs had the same price but no membership fee.

 

[John61CT]

I've shopped at my local Sam's as the "guest" of a member, few times just asked in the parking lot.

Shopping online as a non-member is a 10% surcharge, so break-even for a once-off, is two pairs of GC's.

In any case, lots less than mileage costs, just go to whichever's closest, for me Batteries+ is 3 hours away, and I allocate $1 a mile for budgeting purposes.

 

[Weight]

You need to discount the millage by the pleasure of the individual route, and the pleasure, or not, of the shopping experience at the chosen store. I often drive 15 miles out to visit the B+ store as I enjoy BSing with the owner.