House batteries

[maggie blair]

I have two nine year old house batteries that are not holding a charge. Does it matter the type of batteries I buy to replace the old ones. I have heard golf cart batteries or marine batteries. Any suggestions?

[Kirk W]

You want your batteries to be true, deep cycle batteries. If it were me, I would buy two, 6v golf cart batteries and then connect them in series. You may now have either 6v or 12v batteries and the first are wired in series while the second would be in parallel. If you are not sure, you can easily tell which you have by looking at the top of the batteries. See the pictures, first a 6V and second is a 12v.

 

Notice that the 6v has only one gang of three cell openings while the 12v has two gangs of three cell openings each, for a total of 6 cells.

[GlennWest]

Might want to look into AGM. They are more money but don't off gas.

[Yarome]

You want your batteries to be true, deep cycle batteries. If it were me, I would buy two, 6v golf cart batteries and then connect them in series.

 

Agreed. Depending on the size of your battery compartment there may be some limitations on what size of battery you can actually carry.. measure first, but a true deep cycle battery is going to be the best option for a "house" battery bank. Marine batteries are what some call a "hybrid" battery. A cross between a standard starter battery.. like you would use in an automobile... and a deep cycle.

 

"Big box" stores like Sam's club or Costco sell a fairly inexpensive 6v "golf cart" deep cycle battery that is suitable. For full timers I would generally recommend moving up a class and going with something more like a trojan. They DO cost more, but taken care of properly will last longer, provide more storage capacity over the life of the battery and are generally more reliable.

 

Unless there is a specific 'need' for AGM's, or you're willing to pay more for the convenience of not having to check water levels from time to time, they are generally not worth the additional cost.

 

Just a general comparison... 2-6v "big box" deep cycle batteries will run you right around $160. Trojan class.. $250. AGM's... $600. Doubling that for 4 - 6v's (which is quite common among full timers) you can see the price differences can sting a little right quick.

 

One additional consideration would be availability in the event of a battery failure. With "big box" batteries a single battery replacement of the same make may not always be available. Ie., the golf cart battery sold by Sam's in Florida may not necessarily be the same battery being sold by Sam's in Texas. With Trojan's or the like.. they will be available just about anywhere and a trojan's a trojan.

[skp51443]

One other area where an AGM might be a good buy is if you recharge using a generator and have a high amperage charger. The faster charge rate of an AGM in that situation can cut generator run time so you have less stink, vibration and noise.

[Yarome]

The faster charge rate of an AGM in that situation can cut generator run time

 

Quite true. The lower self discharge rates (1.5-2% vs 10-15%/30) are a plus as well. They can sit for months with no need for "tending". They certainly have distinct advantages if the price doesn't scare you.

 

Even on solar.. with a system capable of producing sufficient current, charge times are significantly reduced.

 

With the way prices are coming down on LFP's though it probably won't be long before the choices narrow to deep cycle wet cells or LFP's over AGM's.

[jayco1]

_{I like less stink, vibration, and noise.}

[Newt]

Maggie, if your batteries have lasted 9 years, you're doing something right.

 

Newt

[Ray,IN]

Maggie, if your batteries have lasted 9 years, you're doing something right.

 

Newt

X2! Maggie, I would buy exactly the same brand, group#, and specs as the old ones. Stay with what has worked very well for you.

[Kirk W]

Maggie, if your batteries have lasted 9 years, you're doing something right.

I believe that Maggie just recently bought the RV and those batteries are in it, but don't hold a charge. Who knows how long it may have been since they were last properly cared for and did hold sufficient charge?

[Sehc]

I purchased six volt golf cart batteries from Batteries Plus Bulbs. $109 each. 230 amp hour rated. Labeled Duracell. Made by East Penn, Deka Battery. Very happy with them during this past year.

[The Quiet Assassin]

Wet cell golf cart batteries are known to give the most bang for your storage buck.Yes they do need to be check regularly and topped up with distilled water.

 

AGM batteries need less attention but need a slightly different charge regime. make sure your charger has the appropriate settings. Not all AGM batteries tolerate deep cycling.

 

Beware of batteries labelled leasure generally they are not really tolerant of deep cycling.

 

If anyone tries to sell you lithium based batteries be really really sure you fully understand the required very specialized charging and individual cell equalizing required.

[Cosmo]

 

Quite true. The lower self discharge rates (1.5-2% vs 10-15%/30) are a plus as well. They can sit for months with no need for "tending". They certainly have distinct advantages if the price doesn't scare you.

 

Even on solar.. with a system capable of producing sufficient current, charge times are significantly reduced.

 

With the way prices are coming down on LFP's though it probably won't be long before the choices narrow to deep cycle wet cells or LFP's over AGM's.

[Cosmo]

What is a "LFP"?

[Darryl&Rita]

Breed of Lithium battery. LiFePo in longhand.

[BigRich]

I have personally used the Trojan 6v, T-105-RE (If you're really on a budget, the T-105 can be had for about $119) with huge success, plus the price is right! I got my entire 200w solar kit and two Trojan 6v deep cycle flooded batteries for about $850 complete. I used the great folks at Solar Penny, solarpenny.com, in Mesa AZ.

 

If you're just looking for batteries, give the Trojans a try. I'm at four years with this set and they're still doing fine. If there isn't a Trojan dealer in your area, call the main office and they can help you.

[olyeller]

I just bought 2 new 12V Interstate Group 74 Deep Cycle batteries at Costco for $79 each. They also had Group 72's for $72 each.

[297550]

Might want to look into AGM. They are more money but don't off gas.

 

Glenn's right ... ZERO maintenance on AGM's and they can be mounted in any orientation. Pricey, but when they say maintenance free, they're not kidding. I use Lifeline, but there are other good manufacturers.