Best Rv batteries

I'll add a point that no one else has made yet, re 6 volt vs 12 volt.

Engine starting batteries are built with many thin lead plates in every cell. This is to maximize the number of square inches of lead in contact with the acid. This is how you get the maximum cranking AMPS out of the battery to power the starter.

6 volt golf cart batteries are TRUE deep cycle batteries, similar to the ones used in floor sweepers, pallet trucks, etc. They are built with very thick, heavy lead plates.

So called RV/Marine batteries are hybrids, with plates that are thicker than an engine starting battery, but not as thick as the plates in a TRUE deep cycle battery.

There are a FEW 12 volt deep cycle batteries - I think Trojan makes a couple models, but they are expensive. 6 volt golf cart batteries enjoy economy of scale, they make so many of them, and it's a very competitive market, which helps keep the price as low as possible.

TRUE deep cycle batteries will give you 1,000 to 1,200 (50%) cycles, whereas RV/Marine batteries will give you 400 or so, and an engine starting battery would be lucky to give you 50 to 75.

New RVs all come with the 12 volt RV/Marine batteries cause they are cheaper for the manufacturers to buy. Savvy full-time RV'ers always replace them with the 6 volt GCs when they go bad.

do you have an inverter ?
if yes, how many watts ?
what do you power with it ? microwave, coffee machine, hair dryer ?

lots of people with CPAP on inverter and batteries

no heavy inverter loads, just TV and/or cpap
6v golf cart batteries will handle that, but my experience is they require a longer recharge time versus 12v AGM for the amount of amphrs used

in the past i have had 6v flooded, 12v flooded, 12v wet SLA, and 12v telco AGM

the telco AGMs have given 'Me' the best service
NEW they are $300 -$400 per battery
surplus 'removed from standby duty' found on craigslist $100 - $150 each

my first set lasted 5yrs of everyday full time over 1800 cycles
my second set is 14mo old in my previous RV

im actively watching craigslist to find some for 'this' RV

What makes this talk difficult is that the OP wants a simple answer. There aren't any. A lot of factors to consider, adequate charging and use being not the least important.

This is like reading an argument between Vegans and Carnivores. There is no beginning and there is no end.

RV jar flooded batteries are preferable in some cases
While GC220 batteries are appropriate in other cases.

AGM has it's place

And Lithium quite another.

Advocates of each type will yell themselves horse. And everyone of them will be both wrong and right.

Gdetrailer, few minor corrections if I may.
There are (many) Li batteries that come with BMS inside. Called "drop-in 12V battery replacement". You just drop it in place of an old battery.

Li have high initial cost, this doesn't make them more expensive because they have much longer cycle life than FLA - again, with proper care.

They are unforgiving to overcharging (95-99% is NOT recommended), over-discharging (avoid discharging below 30%), temps below freezing, temps over 100F, or too high current at the beginning of charging.

Recycling is a big point for those environmentally concerned. Li are so often toted as a part of "green" technology, promoters never mention the fact that Li can not be really recycled.

Lifepo4 is the cats meow. ;)
Perfect for our fulltime living.

Folks sure do like spitting on them just because the they're more suited to fulltime users instead of weekend warriors and come with bigger price tag. As far as recycling goes when the time comes and if there is no place that want or take them in the garbage they'll go right along with AA, AAA, C, D batteries.

1Longbow wrote:
Not looking at price,just the best bang for the buck. ......
Right now 2 12 volt batteries,would 2 6 volts be better?

Yes. For 2 reasons: you will get a little more capacity than 2*12V (assuming you won't buy 6V motorcycle batteries), and 6V like those used in golfcarts have thicker plates.

Several people already mentioned good care as one of the factors making battery "good". It is unlikely that offgrid living with only a generator will make a good care. Consider adding some solar, at least a portable unit. Also, - some charge monitoring.

Hi,

Any temperatures lower than -4 f (-20 c) prevent recharging LI. That eliminates them for me.

If you are running a large inverter then AGM 12 volt wired in a balanced manner would be my choice.

If you do not run heavy loads then golf cart batteries may be best.

1Longbow wrote:
Not looking at price,just the best bang for the buck. Have to run a cpap machine, furnace ,and maybe the TV when its raining out,lights. We do ,some cold weather camping. Right now 2 12 volt batteries,would 2 6 volts be better? Thank you

Lithium batteries are out of my price range so I cannot comment. I wanted the "best" in terms of capacity, durability and no maintenance. I went with AGM and found a size where 2 batteries will barely fit into my battery compartment (after I removed the sliding tray). Maintenance is now out of the question. Since I was a full timer, I went with what my dealer recommended as the best quality and most durable battery. Lifeline, specifically the 30HT size at 150 AHs each. I had a cheap converter/charging that was fixed at 13.3 volts. I also had solar with a fixed 13.6 v charger. I probably shortened the life of my batteries since they were often undercharged and when in storage the float at 13.6v was too high. I got 7 years of use out of them including 2 years of full time use. I ran an electric refrigerator and my wife's cpap, along with the other uses such as computers, lighting and the furnace. I might have tried to extend their life by trying reconditioning but replaced them instead. I think that is about as much as you can expect to get from conventional batteries and at about $900 that should be the case.

2oldman wrote:
Well, there's price, longevity, maintenance, capacity. etc. Best usually means price around here. Lithium is best.

Not necessarily.

EACH "type" of battery has "pros" and "cons", comes down to what best SUITS YOUR "priorities".

IF you have tons of cash laying around and have no cares in the world and don't mind burning it like there is no tomorrow then "Lithium" just might be suited for you.

However for the rest of us poor working slobs, Lithium is STILL way over priced for what you get.

Sometimes if you are simply looking for the HIGHEST BATTERY CAPACITY FOR THE MONEY, FLA (Flooded Lead Acid) technology well surpasses all other battery technologies.

With FLA, the best bang for the buck is the ever so humble Golfcart batteries..

Even paying MORE for a GC battery is dumb, the ones sold at Sams club or Costco ARE the most inexpensive but yet with PROPER care can easily get you 10 to 12 yrs of usable capacity..

Then you have AGM, you pay more, get less capacity for the same size as FLA.. But they do have sever "advantages" in the fact they often can be recharged a bit quicker, can take a bit higher discharge with less voltage drop, can be turned on their sides, do not outgas unless you did something wrong.. However, mistreat AGM and they turn into a expensive doorstop the first time.

Lithium, lighter weight than FLA, can be turned on their side, provides more power density.

Downside is they are insanely expensive, REQUIRE BMS for discharge and recharge, without BMS you run the risk of not only damage to these batteries but overheating to the point of setting either the batteries on fire our your RV on fire.. BMS often times is the failure point of Lithium and most prepackaged Lithium batteries have it built in so if the BMS fails you have no choice but to lay out more money for another battery.

Another "elephant" in the room that pro Lithium folks don't talk about is "recycling", many lithium batteries are not 100% recyclable due to economic costs, it is not economically feasible to recycle them (it costs MORE to recycle than the final product made from all new material).

SEE HERE

Text from link..

"OEMs are looking at overcoming the dependency on lithium through reuse of lithium batteries in other applications (second-life) and through recycling the batteries once they have completed their lifecycle. However, it does not make any economic sense to recycle the batteries. Batteries contain only a small fraction of lithium carbonate as a percent of weight and are inexpensive compared to cobalt or nickel. The average lithium cost associated with Li-ion battery production is less than 3% of the production cost. Intrinsic value for the Li-ion recycling business currently comes from the valuable metals such as cobalt and nickel that are more highly priced than lithium. Due to less demand for lithium and low prices, almost none of the lithium used in consumer batteries is completely recycled.

While lithion is 100% recyclable, currently economics do not add up to recycle it"

ALL of the Lithium used for batteries typically comes from OUTSIDE the US!!! Yep, YOU are now depending on Lithium from OTHER countries, their politics, economy..

From link above..

"Lithium supply and challenges

There are a number of challenges that are likely to impact lithium supply in the future. Although there is sufficient amount of lithium resources available globally to meet the demand, almost 70% of the global lithium deposits are concentrated in South America's ABC (Argentina, Bolivia and Chile) region. This poses an inherent risk due to the accessibility of the raw material that is available only in a specific geography. Unrest or instability of the governments in these regions can greatly affect the supply and have impact on the battery price and in turn, the vehicle cost."

Buy into the Lithium is "best" and is "the best solution" to everything at the risk of your own peril..