CP34

Wondering where you saw/read/learned this? I did a lot of research before I determined what setup I wanted to go with and I never read this. Not saying I'm right or you're wrong but just wondering for my own knowledge.

PerryB

Thanks. My question was in earnest, I figured the charger wouldn't care. The converter in my trailer doesn't seem to know the difference.
As far as 6v vs. 12v, all I can say is my battery life is better with the 6's. Typically I'd get about 3 years out of the 12's before they started to lose duration. In 2010 when we bought our current trailer I did the 6v/T105 swap and just changed them for the first time last summer, so they went a little over 5 years. This time I went with AGM's. Expensive but almost zero gassing and related corrosion

acadianbob

Are you comparing a Trojan 6V to a no-name 12V? That perhaps wasn't a real deep cycle?

My Group 30 12V Trojan is still going strong at 5 years. Not sure I buy into the durability claim on 6V.

SKBORDERS

Exide and interstate battery reps.

I am a heavy duty truck electrical system trainer and work for Delco Remy, manufacturer of starters and alternators. The increase in reserve capacity is why we recommend more batteries with a lower CCA instead of fewer with a higher CCA. This way there is enough cranking power and reserve capacity

A quick search came up with this

https://www.pacificpowerbatteries.co...AQ/dcfaq4.html



Note the two batteries in parallel have double the CCA and more than double the RC. The two batteries in series only yields double the voltage with no increase in either CCA or RC

CP34

I understand most of what you're saying, however I don't see anywhere stating the RC more than doubles when paralleled.

I also for the most part understand the difference between CCA and RC. CCA weren't a factor in my decision as these batteries are for my camper and I don't need CCA, AH were most important to me. In my research, the largest 12V batteries I could fit were Group 29 which had RC25-210 which when doubled in parallel would have been 420. For the same cost, I was able to get two 6V in series with RC25-475.

Anywho, definitely not stating I know anywhere near as much as you do about this stuff. Just like to have a friendly conversation. Thanks for responding.

SKBORDERS

I didn't take it as argumentative.

Here is how it was explained to me:

"...the test for RC is a 25 amp discharge off a fully charged battery at 80 degrees and measuring in minutes how long it takes that battery to fall to 10.5v. If I take that same 25 amp discharge and spread it over 2 batteries each battery is supplying 12.5 amps to the load and because your discharging at a lower rate it takes the bank of two longer to discharge (approximately 400 minutes for 2 180RC batteries or 636 minutes for 3-180 minute batteries). It doesn't matter how high the discharge the science remains the same. Batteries share loads and the more batteries you add, the shallower the individual batteries in the pack are "cycled". "

This comes from a guy who sits on the council that sets the standards for the Heavy Duty battery industry. Ah is RC divided by 2.4

CP34

I've never heard that before but that's very good info. Thanks!

SKBORDERS

No problem. The one thing I like better than learning is sharing what I have learned.