6v or 12v Battery. Confused

Hi Zak..,

There is a Typo on the site that you Linked. There is NO AH Capacity noted, at all. The Reserve Capacity is minutes of run time @ 25 A. Instead of listing this Reserve Capacity in Minutes, they mistakenly list the RC as AH.

In looking at the Interstate site, there is NO AH Capacity listed for this battery either.

It might be about 100 AH, but suggest that you RUN AWAY!

In general, buying the lowest voltage battery that you can will give better results, IMO. Because, if a battery goes bad, and you must replace it, you will be throwing away fewer good cells, usually. And higher voltage batteries have less capacity for a given weight, so, you would wind up with more parallel strings, which is not goos.

Just my opinions, Vic

Saipro wrote: »

I'm new to this RE thing but traditionally, RE batteries usually come in 6V and 2V offerings,with plenty of good reasons. Marine batteries are invariably deep cycle batteries too but aren't manufactured for use in RE applications and typically would not stand to the test. The ones which can double as RE batteries are typically way more expensive yet once again rarely appear in offerings of greater than 8V per battery. I'd say you're better of with your T105-RE batteries (distinctly different from the T105 batteries). Notice the RE suffix? It's common nomenclature you'd find these days and it specifies that the batteries are engineered for RE applications.

If you just look at the weight of the T105 compared to the T105RE, you will see that it has a lot more lead in the plates for long term stability.
Cranking batteries have more thin fragile plates to be able to deliver high current "off the top". But if you discharge them too far the plates will suffer cumulative damage. Same if you chronically overcharge them.
Hybrid (and most Marine batteries, even if they say Deep Cycle) batteries have fewer thicker plates and the active chemicals on the plates are structured to withstand a deeper discharge, but still not the cycle life of a real RE battery.
RE/Deep Cycle batteries have a higher internal resistance than the other two types, but are designed to deliver a lower current through many more discharge/charge cycles for longer life. In some cases the chemical composition of the active material on the plates may be different too.

Vic wrote: »

Hi Zak..,

There is a Typo on the site that you Linked. There is NO AH Capacity noted, at all. The Reserve Capacity is minutes of run time @ 25 A. Instead of listing this Reserve Capacity in Minutes, they mistakenly list the RC as AH.

In looking at the Interstate site, there is NO AH Capacity listed for this battery either.

It might be about 100 AH, but suggest that you RUN AWAY!

In general, buying the lowest voltage battery that you can will give better results, IMO. Because, if a battery goes bad, and you must replace it, you will be throwing away fewer good cells, usually. And higher voltage batteries have less capacity for a given weight, so, you would wind up with more parallel strings, which is not goos.

Just my opinions, Vic

I just looked at the Trojan site and it shows both RC (although not explicitly labelled as that) and the AH at 5 through 100 hour rates. The 225 AH at twenty hours (C₂₀ = 225) looks right for this 6V battery.

Using six volt batteries, you can get a 24V bank using just four in series to get 24 volts and two strings in parallel to get more capacity (550AH).( If you were starting from scratch, I would recommend a 48V battery bank instead, using all eight batteries in a single series string.)
If you try to get the capacity you need at 24 using 12V batteries, you will end up with four series pairs in parallel, and that is generally accepted as a bad idea. It will be hard to get even current distribution over the four strings during both charge and discharge, and that will reduce battery life and require more maintenance attention from you.
You can see a good discussion of batteries in parallel at this site. The rest of the technical pages on the site are great too.