Regarding all the recent "electrical" discussion...

I have heard many opinions regarding what "type" [and voltage] of house battery should be considered as RV replacement(S).

I have heard many recommendations towards 6 Volt Golf Cart Batteries...

Is this primarily a "Space Issue" -or- is it a matter of quality and longevity issue???

If a person has plenty of "SPACE" for ANY type of battery [12 volt -vs- 6 volt], what type of HOUSE Battery is best and will last and perform the longest for the money???

[I currently have 3 - 12 volt Marine-type Gel Batteries, of-which ONE seems-to-be getting HOT, "hissing" and expelling gas and the case might be deformed, as well]

quote:

Originally posted by Medic37:
If a person has plenty of "SPACE" for ANY type of battery [12 volt -vs- 6 volt], what type of HOUSE Battery is best and will last and perform the longest for the money???

5 cent answer: A pair of golf cart batteries.

5 dollar answer: It depends on your use.

Whatever battery you have, it should not be discharged below approx 50% for long life. If you are plugged in most of the time, or run your gen a lot, and don't run your furnaces on battery much, one deep-cycle 12 volter is cost effective. Most 12 volters do not last as long as a pair of golf cart batts, but Trojan has a couple now that use the same plates as their T105 GC batts. I am not sure is is a better value than a pair of GC, though. Trojan prices are quite variable. I have been a Trojan user for decades, but their prices are getting up there, and Sams and Costco offer some pretty good values on golf cart batts. Even if they don't last as long as a Trojan, they look like good value.

If your usage drains one 12-volter below 40-50%, then a pair of golf cart batts is the most cost effective. If you drain a pair below 40-50%, then two pair is one way to go, and so forth.

If a pair of golf cart batts is not enough, then a pair of L16s is good, if you have the vertical clearance. They are not as cost-effective as golf cart batts, due to the marketplace, but they allow you to operate with just two six volters in series, rather than a parallel set up. I do not like parallel charging, but that is a personal quirk, and really is another subject.

My own battery tray is probably going to get four Costco golf cart batteries, which will fill it to capacity. They will perform starting and coach power. My 502 has a gear reduction PM mini starter that draws only 220 amps for 1-2 seconds, so they will do that OK. They are as unlikely to last as long as the Trojans, but their low price makes them appear to be a good value.

Flooded wet lead acid golf cart batteries are the most cost effective. You can do the math on amp hours per dollar, life in years, and tolerance for higher charge rates. They take top honors. There are advantages of other types, but they are not worth the extra cost to me. One advantage of AGM batts is they take a very high charge rate, so if you have a humongous charger, generator run time is minimal. My experience as battery nanny at work for our carts and lifts included no experience with any other types of battery. Our coporate engineers had already decided that GC batts were the most cost-effective if properly nannied.

Flooded lead acid batts require a little care to get maximum life out of them. They need periodic desulfation and equalization, but that is a matter of some discussion. They should not sit either fully charged or discharged. When out in the world, they need not be charged up beyond 80%, as it wastes generator fuel. But they should be brought back up to 100% when you get back home, or at least once a week if you are still out. They should also be discharged down a bit and recharged every month or two if they sit. Different charger and battery manufacturers have differing opinions on the frequency of equalization. I went 5 or 6 years with no equalization. This may sound extreme, but the hydrometer readings stayed pretty close, so I didn't bother. I use both a hydrometer (when it's not broken) and a Midtronics tester (when it is broken) or when I am not wearing my Acid Pants.

Desulfation can be most easily accomplished by a good high amp bulk charge, but that requires a big charger. A good strong bulk charge will pretty much take care of both equalization, electrolyte stratification and desulfation. Equalization also helps desulfate, and is often cited as a method of desulfating. Another way is with an electronic desulfator, either a separate box or with a charger that has that feature. The Vector 1095A has a desulfation feature. I can supply a circuit for anyone inclined to build their own desulfator, and kits are available. They basically introduce an AC component to the batteries. I am a little leery of using them when circuit boards containing fragile ICs are connected. Heck, I don't even like equalizing with circuit boards connected. Then, there is chemical desulfation, such as EDTA. It also works.

Flooded lead acid batts should be charged, or at least finished with a 3 stage charger, the so called "smart" or "IQ" chargers or converters. Before I sprung for a big "smart" charger, I carried a cut-down big shop-type charger for bulk charging, and finished up at home after a trip with a Sears charger that had an automatic deep-cycle setting. This is a pretty economical alternative to a smart charger.

The marine website:

http://www.vonwentzel.net/Battery/01.Type/index.html
Battery Types: Flooded versus AGM and Gel

is an excellent in-depth analysis of the battery-type question meant for yachting types, but equally useful here.

Good site. The cost figures are even more interesting when current local prices are used to get the numbers.

As Rick mentioned, it is for boaters, who use different generators than we do. I was surprised to see no mention of solar considerations in battery choosing.

Here are some more interesting sites:

http://www.ccis.com/home/mnemeth/12volt/12volt.htm

http://www.uuhome.de/william.darden/index.htm

http://www.batteryuniversity.com/

http://www.batteryweb.com/faqbw.cfm#q12

http://www.marine-electronics.net/techarticle/battery_faq/b_faq.htm

More stuff:

http://www.type2.com/library/electrip/battbas.htm (you've gotta love a guy who writes, intentionally or otherwise, "Inadequate battery reserve power has long been the Achilles' hell of RVers.")

http://articles.mbz.org/electric/batteries/

http://www.batterystuff.com/tutorial_battery.html


6V - 12V Battery Comparison - (44 KB) ~ 6V - 12V Battery Comparison

Since I am unable to post more than one attachment at a time, here is a color graphic that illustrates some of the info in the boring chart 1 on the mbz.org site above.

Hey Bill:

I used Costco golf cart batteries for about 3 months and changed to Trojans, I have 4 of them and the issue that I had with the Costco batteries was they didn't have the high load voltage stability that the Trojans do. When I first bought them (Costco's)with about 100 amp load, the voltage would drop to about 11.7 volts and maybe move up a bit after about 10 minutes. This did improve a bit after a dozen recharges but was still under 12 volts with that load.

With the Trojans, right off the shelf they only dipped to 12 volts under the same load condition and now after several charge cycles the voltage will only dip to 12.3 and slowly go up toward 12.5.

These conditions were monitored with the same equipment and under the same load conditions. The tests were always started after the batteries were at full charge using an intellicharger a hydrometer to confirm.

You may wonder why I am concerned about voltage under such a high load? I am a han radio guy and I run both FM on VHF and UHF and SSB on the low bands. I run a good 500 watts on FM and 1000 watts peak on SSB. When the battery voltage drops below 12 volts the amplifiers I use don't like it and shut down.

With the 4 Trojans I run the coffee maker in the morning thru an inverter and also can run the microwave. I am getting a true sine wave inverter soon because the microwave works but doesn't have nearly the output power with the quasi-sine wave inverter that I have now.

Thanks, Ed. That's good information, even if it is not what I want to hear. It sort of confirms my feelings that the Costco batts would not last as long as Trojans. We don't load our batteries that much, but I suspect that the Trojan advantage you cite translates into longer life and better reliability, especially if I use them for cranking. Maybe I'll have to bite the bullet and pay the big bucks for Trojans again. But not until I have seen how long the present set will last.

BTW, have you tried a French Press for coffee? Pretty low electric draw and pretty good taste.

NO I haven't tried French Press, sound like I should, thanks for the tip.

BTW, I found a place here in San Jose that I got Trojans and the price wasn't all that bad, I will find the receipt and get back to you.