12v vs 6v battery construction differences?

[Eastward ho 24]

Generally speaking: Are the 6v golf cart battery's constructed the same as a 12v? Are cruisers using the 6v just because they're easier to handle? Ex Trojan 105 vs Trojan t1275 . The 12v has slightly more ah then the 6v made into 12v would? Or are the GC batteries actually made better and perform better thus making them a better selection? I don't plan on lugging batteries in and out , on and off the boat so that's no concern. I'm strong enough to pull the heaviest battery out of odd places so that's of no concern either. I figure the 12v battery will have less wires, less connections less things to go wrong, and less battery's to worry about one going down spoiling the lot. This is just a general question with out getting to technical. I'm thinking bigger is better or am I wrong? I'm thinking Trojan j185h ac is the best option if it fits?

[Maine Sail]

The T1275 is one of Trojan's 12V golf car batteries and is constructed just like a T105, only with six cells instead of just three. On a $ to Ah calculation the the T1275 sometimes cost a bit more. "Lab" rated cycle life is identical between the T1275 and the T105, both rated at 1200 cycles to 50% DOD.

[denverd0n]

One of the big issues is that the 6-volt, golf cart batteries are always true deep cycle batteries. Trojan is clear about what their different batteries are made for, but a lot of the less expensive 12-volt "deep cycle" batteries barely qualify as "deep cycle." They are, in reality, more like "dual-purpose" batteries that try to balance between deep cycle and starting capability.

[a64pilot]

Just be careful with 12V batteries, very few are actual deep cycle batteries, and they tend to not be inexpensive, Trojan, Rolls and Lifeline manufacture true deep cycle 12VDC batteries, not sure how many others do.

I’d argue that most 12VDC batteries sold as either deep cycle or dual use are actually identical to the starter battery, difference being the label.
They do work, just for not as long. I’m not sure there is actually such a thing as a dual use battery.

Usually great deals can be had on much less expensive 6V traction batteries, AKA golf cart, so you can get just as good or very close to as good a battery for much less $$ per AH with a Costco or Sam’s Club golf cart battery.
It’s the money saving that drives most to golf cart batteries in my opinion.
I would use Golf Cart batteries myself, except my battery box isn’t tall enough, so I’d have to reconstruct my box.

[Maine Sail]

Originally Posted by denverd0n

One of the big issues is that the 6-volt, golf cart batteries are always true deep cycle batteries. Trojan is clear about what their different batteries are made for, but a lot of the less expensive 12-volt "deep cycle" batteries barely qualify as "deep cycle." They are, in reality, more like "dual-purpose" batteries that try to balance between deep cycle and starting capability.

Yes their "automotive cased" batteries, such as the SCS line or the TMX line (BCI Groups 24, 27 & 31), are lab rated for half the cycles of the T1275 or T105 golf car batteries..


This may help:
What is a Deep Cycle Battery?


As can bes seen below the T1275 or the J150 are in the BCI class GC12 or golf-car 12V. The T1275 & J150 have the same lab rated cycle life to the T105.


Far too often folks forget that 12V golf car batteries do exist. The BCI class is GC12.

Here's a rebadged (Duracell sticker) East Penn GC12 next to a Group 29/30/31 East Penn automative cased battery..


.

[zstine]

I have some opinions on this. I purchased 3 duracel ultra 12v golf cart batteries, 155amp hr each, before leaving NJ and sailing to the Caribbean. I discovered one battery had a bad cell, after too low of voltages. You cannot easily buy 12v golf cart batteris with 150Ahr capacity in the caribbean. I had to wait, using 2 batteries (300amp hr), for months until I got up to Puerto Rico where just yesterday I was able to replace the battery Battery + Bulbs part GC12T $280. If I had tossed the start battery, which was 1 yr old and I didn't want to, I could have put in four 6V batteries and easily replaced a failure. ... my point is that if you are sailing away, make sure you don't put something too fancy/unusual in because you can't find replacements.

[shelleyWendert]

they aren't superior or inferior to each other. simply, a 12v battery winds up being extremely heavy for the same amount of capacity as the 6v counterparts are and so it is easier to lift 2 100lb 6v batteries than 1 200lb 12v battery. one could take this down to the comparison of 6v batteries and 2v cells as well. it's just easier to carry is all.

[Eastward ho 24]

Interesting...

[roland stockham]

In theory the same quality and construction would mean there would be no difference between 6 & 12v. In practice not so much. My example. I have 12 Trojan 6v 280a/h batteries. I can fit them using a tackle to lower them from the deck then 'walk' them into final position. If I had a single 12v it would be impossible to fit.
The alternative would be to use 2 12v batteries but in practice this would be twice the footprint as you cant get the tall ones in 12v. Also each cell would be half the size. While it is possible to build a cell half the size with the same thickness plate in practice it seams that for smaller capacity batteries you get thinner plates and light weight construction that means a less robust battery.
To be fair I don't work in battery manufacture and have never seen the inside of one so this is just what seams the case from my observation but I would say 6v cells do better than 12v and in larger capacities I would go for 2v so that I always aimed for a single string.