Need battery recommendations...

navigator97 · Jun 6, 2012

I have put in 2 Group 27 Deep Cycle Marine Die-Hard Lead-Acid batteries from Sears. They were about $90 to $100. They have been in since May 2006 - 6 full seasons and maybe a 7th coming up. I have been satisfied with them. I keep the level topped off with distilled water (twice a year I check and add if needed). In the Fall I top off the charge of each with a 3 stage charger well into stage 3. They hold for the winter with the battery wiring disconnected. I only lose about ).1 Volt 10 a max of 0.2 Volt over the winter

Stu Jackson · Jun 6, 2012

Don't waste your $$ at WM for batteries.

http://forums.catalina.sailboatowners.com/showthread.php?t=132350

galynd · Jun 6, 2012

A couple of 6 volt Sam's batteries is hard to beat. Probably about the same footprint.

centerline · Jun 6, 2012

weinie said:
I am looking to replace my 2 group 24 batteries with 2 deep cycle batteries for both house and starting use.
I would like to stay with group 24s since my battery compartment is built for that size footprint, though I know I would have more options with a larger size.
Anyone have any suggestions?
(Currently, I've been using 2 westmarine starting batteries, but have since added things like an autopilot.)

in all due respect to the question, the only way to properly answer it is to purchase the best batteries you can afford..... find a dedicated battery store in your area and talk with them. they are more than willing to help you and they wont sell you junk.....
all modern group 24's have the same foot print within a half an inch.....
if you want a brand recomendation, try trojan batteries. they cost a lot to purchase today, but properly maintained, over the life of the batteries, they are the cheapest.... and they will outlast all other common batteries on the market.
but keep in mind that even the best, strongest and longest lasting battery mone can buy, is no match for even a slightly faulty electrical system.....

Benny17441 · Jun 6, 2012

If your needs are met by two group 24 there is really no reason to upgrade and you can stay with the footprint thefits your boat. I would venture to guess that you are mostly a daysailor with a few overnight or weekend trips throughout the year. I would recommend 2 12V deep cycle group 24 wet cell batteries. Interstate makes afordable quality batteries. As a coastal cruiser I just keep 2 group 27s as there are enough marinas from Texas to Maine to recharge nightly if so desired. Conduct a power survey on your boat and if your usage in a 24 hour period or between recharges is less than 85 a/h you will be fine. The deep cycles will start your diesel engine fine. Now the autopilot can be a power hog on its more sensitive setting. Take its average usage into account for the power survey. If you need more than 85 a/h between recharges you may need to move up to Group 27s. I like 6V batteries but you would need 4 of them to provide the backup you get from 2 12V. Unless you have the space and the need I don't think the added expense is warranted. I'm not a fan of lugging extral lead around.

JVB · Jun 7, 2012

Solid plates for deep discharge

For maximum starting amperage use an automotive battery. Those have fine grain plates, in other words lots of surface area to react with the acid.
For maximum durability when deeply discharged use a golf cart battery. They have solid plates which are resistant to damage.
For a compromise use the so-called "marine" batteries which have coarse grained plates. They can tolerate a little deep discharging but not nearly as well as a golf cart battery.

So your best bet for 'house' batteries is golf cart batteries. If you must have high amps for starting then go with "marine" or automotive batteries.

http://batteryuniversity.com/learn/article/getting_to_know_the_battery

sea_casper · Jun 9, 2012

Do the math

Benny17441 said:
I like 6V batteries but you would need 4 of them to provide the backup you get from 2 12V. Unless you have the space and the need I don't think the added expense is warranted. I'm not a fan of lugging extral lead around.

Two 6 v bats @ 220 ah replaced my two group 29, 12 v @ 95 ah at less than 1x the cost and only slightly more weight. Two more will more than double my original capacity. The battery lead weight is insignificant to the weight of my lead keel.

Bill Roosa · Jun 9, 2012

I believe you only get 110 AH out of your 2-6 volt 110 AH batts hooked up to provide 12 volts not 220 AH
AH does not add in a series connection. It does add in a parallel connection though

Bill Roosa · Jun 9, 2012

Deep cycle batteries work fine at starting a small diesel engine. You don't need a starter battery unless you want to start under colder conditions.
Consider the starting load of 100 amps (typical)for 5 seconds vs the first mate running a 1000 watt hair dryer for 10 minutes.
starting is a blip compared to the morning ritual.

Maine Sail · Jun 9, 2012

Bill Roosa said:
I believe you only get 110 AH out of your 2-6 volt 110 AH batts hooked up to provide 12 volts not 220 AH
AH does not add in a series connection. It does add in a parallel connection though

Bill,

Most all 6V batteries in the GC2/T105 case size are between 215Ah and 230Ah each @6V. Two in series yields one batteries Ah rating. If his batteries are 220Ah 6V and he has two of them in series then he has 220Ah at 12V..

sea_casper · Jun 10, 2012

Bill Roosa said:
I believe you only get 110 AH out of your 2-6 volt 110 AH batts hooked up to provide 12 volts not 220 AH
AH does not add in a series connection. It does add in a parallel connection though

They don't add, that is correct, but they also don't divide, two 6v 220 AH batteries in series yield 12v and 220 AH. Four batteries would be 12v and 440 AH, each battery is $80.