12v to 6v review?

[SabreCanuck]

Currently have 2-12v 7ear old batteries that appear to be getting weak. Am thinking of replacing with 2-6v GC batteries (or maybe 4).
Anyone have experience or real world review of moving to the 6’s?

FWIW - I understand the wiring process, have solar, battery monitor, etc etc. Just curious of the pros/cons between the two systems if anyone made the move.

[JimK-NY]

mr_andyj wrote:
No reason to even consider NOT using two 6's.
Use two 6's!......

I have some reasons. First, I have read a lot of opinions, guesses and statements, but no facts or testing results to back them up.

Second, I have limited space and so do many other smaller RVs. I was able to remove the sliding tray and just fit 2 Lifeline AGM 12 volt batteries @ 150 AH each. My compartment gives me 1/2" clearance in height, 1/4" clearance in depth and about an 1 inch clearance in width. There are no other batteries and certainly no 6 volt batteries that would fit and have anywhere near the capacity.

6 volt batteries are often substantially larger for the amount of capacity provided.

[Boon_Docker]

SabreCanuck wrote:

mr_andyj wrote:
No reason to even consider NOT using two 6's.
Use two 6's!

As stated, you obviously lack research ability as this has been discussed and a search will turn up lots of answers, most all in favor of the 6's.

GC batts (any true deep cycle batt), never, never, never Marine batteries unless you are on a boat using one battery for engine and trolling.

You could get three 4 volt too.

Thank you for your feedback... Interesting how you completely missed answering my question regarding "any real world reviews" and my comments about "I already understand the concept" to respond with spouted data from the 1000's of posts that me and you have both already read. Then took the time to call me out for MY lack of research to a topic that is not only asking for but also named "review" in the subject line.

I truly hope in the future you can see the forest for the trees and that someone somewhere out there gives you a nice big warm bear hug to make you feel better.

I will look into the 4v battery suggestion... LOL.

A post calling you out is not removed, but my post "More sarcasm, just what we need" after you were called out gets deleted.
Go figure.

[ktmrfs]

BFL13 wrote:
I find the Can Tire 230AH 6s are great at a good price, although they have gone up $25 recently. They are East Penn Deka GC15s. I have four and no problems with running the MW etc with a 2000w inverter.

You do have problems with only two 6s, but not with four down to 50% SOC. If you ran the batts down lower than 50% then the inverter alarm would sound even with four 6s.

Can Tire has recently added a 215AH 6, which is at a very good price, looking at 230 vs 215, but I don't know if it is an East Penn. If it is, that would be the better deal with four of those.

Hit the nail on the head on inverter use with GC. I also have four 6V and they run a 800VA load on the inverter down to near 50% as well, but with only two it would shut down around 80%.

I can easily live with the 50% limit. 80%, nope, to much hassle.

[ktmrfs]

SabreCanuck wrote:
Thank you all for the feedback. We have 500 w solar, 2k gennie as backup and a 2k inverter and have dry camped indefinitely in the past. Our plan is to do more boondocking, and to be honest I just NEED to replace the 2-12v but as always thinking of ways to make it “better”. I agree with some here that MOST of these conversations are way more advanced than most users would care about, probably including myself.

I think either way, I’m going to ramp up the number of batteries to 4 and base the rest of the conversation on cost and ease of use.

To be honest, I have only ever touched the 2-12v batteries twice per year (take them out for winter, put them in for summer) and they have lasted 7 years now. But I also have a trimetric battery monitor so keep an eye on them that way I guess.

Given your experience with 12V , and with the dry camping, but seeming to have been satisfied with the 12V in the past, I'd say it is somewhat of a tossup.

Take a look at battery cost, and based on my experience doing lots of boondocking, and trying to rely on solar as much as possible with genny backup, the extra deep discharge capability of the 6V (easily go hundreds of cycles down to 50% SOC and even hundreds down to 25% SOC) we go with Four 6V. But last time I bought batteries cost wasn't much of an issue, and the Trojans are now going on 10 years use with probably 3 months camping/year.
But battery prices have REALLY gone up in the last few years.

[ktmrfs]

mr_andyj wrote:
No reason to even consider NOT using two 6's.
Use two 6's!
.

No reason to not consider two 6V is a VERY VERY MISLEADING AND POOR STATEMENT!

reasons NOT to consider two 6V

1) seldom boondock or dry camp, a single or pair of 12V will be more than adequate and be less expensive in the long run.

2) You want to have high current draw for big inverter loads, e.g. run a microwave, coffee pot etc. or other loads more than about 50A. For these a 6V is NOT a good choice, high internal resistance and no current load sharing with a single bank is an invitation for inverter shutdown at about 80% SOC, while a pair of 12V will really not have much voltage drop, each battery is only supplying 1/2 the current and with more thin plates has much less internal resistance.
Alternate solution is Four GC, but that takes up lots of space, expensive and heavy.
3) Battery compartment won't fit a pair of 6V. There are trailers where 6V are a very very tight fit and the hassle may not be worth the effort.

So YES THERE ARE VERY VALID REASONS WHY A 6V IS NOT THE UNIVERSAL END ALL BE ALL SOLUTION!

STATEMENTS LIKE YOURS ARE WHY PEOPLE MAKE BAD CHOICES ON BATTERIES!

Each battery type has + and - attributes, gain something loose something. Good when you gain what you want but bad when you LOOSE what is important to YOUR specific application.

[BFL13]

I find the Can Tire 230AH 6s are great at a good price, although they have gone up $25 recently. They are East Penn Deka GC15s. I have four and no problems with running the MW etc with a 2000w inverter.

You do have problems with only two 6s, but not with four down to 50% SOC. If you ran the batts down lower than 50% then the inverter alarm would sound even with four 6s.

Can Tire has recently added a 215AH 6, which is at a very good price, looking at 230 vs 215, but I don't know if it is an East Penn. If it is, that would be the better deal with four of those.

[SabreCanuck]

mr_andyj wrote:
No reason to even consider NOT using two 6's.
Use two 6's!

As stated, you obviously lack research ability as this has been discussed and a search will turn up lots of answers, most all in favor of the 6's.

GC batts (any true deep cycle batt), never, never, never Marine batteries unless you are on a boat using one battery for engine and trolling.

You could get three 4 volt too.

Thank you for your feedback... Interesting how you completely missed answering my question regarding "any real world reviews" and my comments about "I already understand the concept" to respond with spouted data from the 1000's of posts that me and you have both already read. Then took the time to call me out for MY lack of research to a topic that is not only asking for but also named "review" in the subject line.

I truly hope in the future you can see the forest for the trees and that someone somewhere out there gives you a nice big warm bear hug to make you feel better.

I will look into the 4v battery suggestion... LOL.

[mr_andyj]

No reason to even consider NOT using two 6's.
Use two 6's!

As stated, you obviously lack research ability as this has been discussed and a search will turn up lots of answers, most all in favor of the 6's.

GC batts (any true deep cycle batt), never, never, never Marine batteries unless you are on a boat using one battery for engine and trolling.

You could get three 4 volt too.

[SabreCanuck]

Thank you all for the feedback. We have 500 w solar, 2k gennie as backup and a 2k inverter and have dry camped indefinitely in the past. Our plan is to do more boondocking, and to be honest I just NEED to replace the 2-12v but as always thinking of ways to make it “better”. I agree with some here that MOST of these conversations are way more advanced than most users would care about, probably including myself.

I think either way, I’m going to ramp up the number of batteries to 4 and base the rest of the conversation on cost and ease of use.

To be honest, I have only ever touched the 2-12v batteries twice per year (take them out for winter, put them in for summer) and they have lasted 7 years now. But I also have a trimetric battery monitor so keep an eye on them that way I guess.

[SabreCanuck]

pianotuna wrote:
SabreCanuck,

What matters is available amp-hours. Pick what ever gives you that in a deep cycle battery.

There is one caveat. If you are running a LARGE inverter (3000 watts) then 12 volt batteries may yield a longer run time.

My OEM battery drawer had room for three batteries--so I chose 12 volt because that gave me the greatest number of amp-hours.

To be honest, I hadn’t heard about the quick draw issue with 6v on an inverter. We do have a 2K inverter and have been known to run a toaster in the am. I will add this to the list of considerations. Thanks

[MEXICOWANDERER]

Then comes L-16's and finally 2-volt cells. In one way or another all choices involve compromises and it's the consumers responsibility to learn those compromises then make a choice of the least evil shortcoming.

Allow me an example. My car needed a battery. LTH sells 65 amp hour group 34 batteries here for about $90 including tax in Costco. Costco USA sells 80 amp hour batteries for a hundred dollars plus tax. Definitely a heavier weighing battery. The kicker (for me) is an 18 month free guarantee in Mexico and a 48 month free guarantee in the USA.

The only 6 cell battery I'm aware of in an automotive group size that has golf car type cell construction is a Rolls and Surrete. Folks who wish to refer to accurate information regarding wet batteries should download the free Rolls maintenance manual off the web. But keep in mind it is for golf car and heavier recyclable batteries.
When properly cared for good quality batteries give phenomenal life.
And remember when it's too hot to park in the sun, roof top solar panels are useless.

[dedmiston]

SabreCanuck wrote:
Thanks for that. That’s actually why i was considering 4 6v but then adding cost again. Interesting to hear that it actually happened to you and not just here say

The circumstances were pretty avoidable, but so are most of life's bummers.

The first time was when my young (at the time) daughter learned that I'd installed a new inverter, so she fired up the toaster using the inverter instead of running the generator. She made toast for the whole family of five, and then reported "a funny smell and weird sound".

The positive connection to one of the 6v batteries must have been loose or something, because the prolonged use of the toaster got the cable so hot that it literally melted the positive terminal off of the battery. It looked like something from The Terminator.

I don't even remember what happened the second time, but it was a similar failure.

That was in our old trailer when our kids were young and rough on our systems. The kids are all grown and gone now. We haven't had any issues in our "new" (five year old) fiver.

[Grit_dog]

ktmrfs wrote:


well I'll disagree. the drawback to 6V is high internal resistance compared to 12V. So if your normal draw is in the 10-30A range, 6V are great. Take a pair of 6V and try to draw 100A for a microwave inverter load, and you'll quickly discover the drawback. At around 80% SOC the inverter is likely to shut down due to low voltage.
This is also impacted by the fact that under such a load with 12V you likely have a pair of 12V so each only needs to supply 50A, unlike the 6V bank needing to supply the total load from each battery.
So for heavy loads 12V may win or 4 GC-2's (500AH).

6V win on deep discharge (500 cycles at 75% DOD) and life, but not on heavy current draw

True statement that I didn't consider, if folks are running a large inverter off of 6Vs.

But to jimk and your points about battery life, not everyone, actually no one I know except the in depth discussions on this board, actually are regimented in their battery care and conditioning and 6Vs tolerate more "abuse" and lower SOC rtes much better than 12Vs.

[JimK-NY]

ktmrfs wrote:


..when comparing life cycles trojan true deep cycle 12V vs trojan 6V the 6V has about double the life cycle discharges vs. the 12V. Now that said, either probably gives way more cycles than the vast majority of RV users will experience before age ends battery life. The 6V has about 500 cycles to 25% SOC...

I know nothing about Trojan batteries. I don't even know if you are referring to flooded or AGM batteries. I did check my Lifeline manual and for 25% the life expectancy does indeed drop to about 500 cycles. I rarely go below 50% and typically I am 75% or greater. That gives me about 2000 cycles and I am unlikely to hit anywhere near that amount in 10 years or so that I would expect to keep the batteries.

[ktmrfs]

JimK-NY wrote:
You will find many conflicting opinions on this subject. Most of the opinions will justify what choice the individual made. I do not think there is any data which demonstrates 6 volt batteries will perform better or last longer than equivalently sized deep cycle 12 volt batteries.

My battery compartment is relatively small so I picked a pair of 12v batteries that totally filled the compartment after I discarded the sliding tray to make more room. I also opted for AGM batteries because I did not want to check or maintain the batteries. At this point I open the door to the compartment once every year or so just to be sure there is no issue with the wiring or corrosion. I also opted for the best quality batteries with a good reputation: Lifeline. Now my only maintenance or concern is to be sure I fully charge the batteries at least every few days of use.

when comparing life cycles trojan true deep cycle 12V vs trojan 6V the 6V has about double the life cycle discharges vs. the 12V. Now that said, either probably gives way more cycles than the vast majority of RV users will experience before age ends battery life. The 6V has about 500 cycles to 25% SOC,

But as I mentioned in a previous post 12V have a distinct advantage with high current draw applications, way lower internal resistance and current usually divided amongst more batteries.

So pick what best fits your use application.