Battery Question Number 92,457

[DrB]

My batteries are nearing their end. I want to replace them and I am frugal. I don't do extended cruising, mostly day sails with a couple of overnights each year. I am never really more than a few hours from land and don't run a lot of electronics.

Typically I run a GPS, wind indicator and depth meter when sailing. I do have auto pilot, a VHS, and Radar, but seldom turn them on.

My current batteries are Nautilus (Deep Cycle) that are 4 and 5 years old. The 5 year old battery has about 1 h of time for a simple car stereo. Even with repeated chargeing, it often won't start my motor. The other battery seems to be okay and has sufficient power to start my motor (Yanmar Diesel 3GM30) and run the electronic gizmos for a couple of hours.

I looked at a variety of batteries based on advice here on Sailnet. Since I am frugal, I thought a Seavolt Deep Cycle Group 27 with the following specs.

Group 27, 80 Ah, 745 MCA, 150 Res. Min.,

Or a Sears Diehard Marine:

Power Ratings:
Cold Cranking Amps (CCA at 0 deg.F): 575
Reserve Capacity (RC): 180 min.
Amp Hours at 20 Hour Rate: 105

The Diehard is $20 less than the Seavolt. ($119 vs $99)

I looked for other batteries in Walmart, NAPA, Pep Boys, etc., but could not find any that were suitable.

The Diehard has fewer CCA than the current batteries and the Seavolt, but a longer Reserve Capacity and more amp hours. The number of CCA needed to start the Yanmar is about 90 or so, so 575 is still 5X that number.

Suggestions?

DrB

[SteveInMD]

There are other people here that can give you great advice on which battery to buy. I would like to comment that you shouldn't wait as long as you did to replace your bad battery. If you have to charge it for hours just so it will only run a car stereo for an hour, the battery is totally shot. It just acts like a larger resistor, which just creates heat with all the power you throw at it while charging. This puts a big load on your alternator and or charger, creating more heat and shortening their life spans. It's one of those penny wise and a pound foolish things.

[SEMIJim]

I am reminded of the boat I crewed on years and years ago. One of the batteries was dead and the other--well, I'm guessing it wasn't in too good a shape, being as when we'd been out sailing one day, went to fire-up the engine to come back in, not enough battery to do it.

We, too, have only two batteries. They're marine batteries of some flavour. Each is only a Group 24. One is brand new last season. The other "looks" pretty new. They will get upgraded before we more than overnight a single night out on the lake. (I'll probably add a 3rd battery, paralleled with the #2 battery, to become our "house bank.") I don't want to be calling Sea Tow for a "jump." (It wouldn't be just impractical to get to our slip under sail, but down-right irresponsible to try.)

Jim

[camaraderie]

Replace both with group 27 deep cycle batteries and I would suggest going to Costco or Sams for a good deal. It makes no sense for you to get "good" batteries given your use pattern and you'll get as good performance out of the discount batteries as you will anything from West or Sears.

[RAGTIMEDON]

Since I am still limited to weekend trips (Work is the curse of the drinking class) I have used Costco group 27's for the last 7-8 years. I may upgrade to 6 volt golf cart batteries when I retire and live aboard summers in the Great Lakes, but 4 lower priced Costco batteries work very well for weekends, even running a 110 volt undercounter refrigerator with a 1500 watt inverter purchased at Costco! I keep wondering how many batteries I would need to add to operate my A C unit for 2 days!

[btrayfors]

"I keep wondering how many batteries I would need to add to operate my A C unit for 2 days!"

More than you could carry on a 37-footer :-)

Bill

[kjell72]

if you dont do extended cruising it is best to get cheap deep cycle batteries and try to take care of them.
If you want good batteries the only way to go is gel.

I fought with different types for 3 years crossing the pacific and ended up with envy of my french friend with only one gel battery, you can even add. batteries later on the same circuit if it is gel.
read about my batteries on my webpage, search for spetakkel and trafficated on google.

kjell

[sailingdog]

I disagree... gel batteries have the worst characteristics both wet cell and agm batteries, with little of the benefits.

Originally Posted by kjell72

if you dont do extended cruising it is best to get cheap deep cycle batteries and try to take care of them.
If you want good batteries the only way to go is gel.

I fought with different types for 3 years crossing the pacific and ended up with envy of my french friend with only one gel battery, you can even add. batteries later on the same circuit if it is gel.
read about my batteries on my webpage, search for spetakkel and trafficated on google.

kjell

[SteveInMD]

For a frugal person, stick with standard wet cells. Try to avoid "maintenance free" batteries. If you take proper care of them (charging, water, avoid deep cycling them, etc.) you will get the most amp hours per dollar spent.