New Batteries

[tyson904]

Hello all.

I have a 17 Cobalt R5 Surf and it is time to change the batteries out. Who makes the best battery? Do I go lithium? What company’s should I stay away from.

Thanks in advance

We mostly boat at Norris Lake in Tenn and then return to the boat lift.

[jhnmdahl]

I think there are really only a few battery makers out there, labeled as lots of things (Johnson Controls, Delphi, East Penn, Exide?). Johnson controls brands include Duralast, Interstate, Diehard, Kirkland, Motocraft, and others, and I've just bought Interstate dual purpose marine batteries from Costco for cheap.

In addition to the dual-purpose batteries like I get, there are dedicated starter batteries and deep cycle batteries. Starter batteries are configured to provide short bursts of high current (e.g., with many thin plates), while deep cycle batteries are configured to provide power for long stretches and discharge more deeply (e.g. with fewer, thicker plates). Dual purpose sort of split the difference, and do so fairly well but don't like to be fully discharged.

If you want to spend money on "the best" rather than see them as a sort of commodity replaceable, there's Optima Bluetop - https://www.optimabatteries.com/product ... ype=marine

[bruceb58]

I use the Duracell 31 series AGM batteries from Sam's Club. They are Deka(East Penn) batteries. If you want the best battery, go with Odyssey.

Optima used to be good until they moved manufacturing to Mexico. My friend used to buy Optimas by the pallet load for his business. When he started getting 2 or 3 Optimas DOA, he switched battery manufacturers.

There are some lithiums that can be used as a starter battery. I love lithium batteries for house batteries but they aren't really ready for prime time as starting batteries for large engines. Charging it will be the biggest issue as you can't really do a direct from alternator to battery connection since the lithium battery will sink too much current from the alternator. You would have to install a DC to DC converter to prevent alternator damage.

And I know there is going to be someone that comes a long and says the Sam's Club Duracell battery uses recycled lead or some other nonsense. That is a myth. Not sure how that got started but it gets perpetuated on boating sites as fact.

[Titaniumboy]

I believe all the lead acid battery manufacturers use recycled lead. The last remaining US lead smelter was closed a decade ago.

[bruceb58]

I believe all the lead acid battery manufacturers use recycled lead. The last remaining US lead smelter was closed a decade ago.

Yes..that is likely true. What I was pointing out is that some people claim the Sam's Club Duracell batteries are somehow worse than ones you buy from a battery shop because of it.

[jhnmdahl]

I figured Duracell car and boat batteries were just a money grab to trade on the good name of their AA, 9V, etc. consumer batteries, but their lead acid batteries are pretty consistently rated highly by places like Consumer Reports that do actual testing.

[bruceb58]

I figured Duracell car and boat batteries were just a money grab to trade on the good name of their AA, 9V, etc. consumer batteries, but their lead acid batteries are pretty consistently rated highly by places like Consumer Reports that do actual testing.

Just a rebranded Deka(EastPenn) Tons of them around. Napa AGMs are also rebranded Deka(EastPenn).

[tyson904]

Great info guys thanks so much. I will go take a look at both Sam’s and Costco as I have access to both memberships. I forgot about charging the lithium with the alternator, I will steer clear from those now and take your advice you guys gave me.

Thanks

[tyson904]

Which Interstate batteries where you talking about 27DC Marine Battery or the 24DC Marine Battery
Thanks.

I think there are really only a few battery makers out there, labeled as lots of things (Johnson Controls, Delphi, East Penn, Exide?). Johnson controls brands include Duralast, Interstate, Diehard, Kirkland, Motocraft, and others, and I've just bought Interstate dual purpose marine batteries from Costco for cheap.

In addition to the dual-purpose batteries like I get, there are dedicated starter batteries and deep cycle batteries. Starter batteries are configured to provide short bursts of high current (e.g., with many thin plates), while deep cycle batteries are configured to provide power for long stretches and discharge more deeply (e.g. with fewer, thicker plates). Dual purpose sort of split the difference, and do so fairly well but don't like to be fully discharged.

If you want to spend money on "the best" rather than see them as a sort of commodity replaceable, there's Optima Bluetop - https://www.optimabatteries.com/product ... ype=marine

[bruceb58]

You need to look at your owners manual to see what the Marine Cold Cranking Amp spec is for your engine. For my Mercruiser, the spec is minimum 800MCCA. The Interstate size 27 deep cycle has only 750. The reason is that some batteries have too much voltage drop while cranking to reliably operate fuel injection and ignition during cranking. That's also why some people buy one starting battery and one DC battery.

Back when I was looking, Costco didn't carry large AGM marine batteries if that is what you are after. They do have the non AGM marine.

[jhnmdahl]

Which Interstate batteries where you talking about 27DC Marine Battery or the 24DC Marine Battery
Thanks.

They're the same construction and materials inside, only the group 27 battery is a bit wider than the group 24 battery so delivers a few more amps. Group 27 batteries will usually fit in the same battery tray or box as a group 24 battery, so if the cost is close it may be desirable to go with the group 27. I think my boat came with one group 24 battery, and I added a second group 24 battery which seems to be plenty of reserve power for how I use my boat.

[SportDek]

I have the Optima BLUETOP® D34M. It is a dual purpose battery. It is designed to work well in a Marine enviornment with all the bouncing around. I have had it for several years now. It has never let me down even after playing the stero for hours at the sand bar. The only maintenance I do is take it out for the winter and charge it about every 6 weeks. I bought a back up one a couple of years ago, but have never needed it.

[jhnmdahl]

You need to look at your owners manual to see what the Marine Cold Cranking Amp spec is for your engine. For my Mercruiser, the spec is minimum 800MCCA. The Interstate size 27 deep cycle has only 750. The reason is that some batteries have too much voltage drop while cranking to reliably operate fuel injection and ignition during cranking. That's also why some people buy one starting battery and one DC battery.

Back when I was looking, Costco didn't carry large AGM marine batteries if that is what you are after. They do have the non AGM marine.

Bruce makes several good points as usual. My Volvo Penta V8 5.7L requires 650CCA, so either a group 24 (supplied with the boat) or a group 27 would work. I have a battery switch that allows me to combine group 24 batteries, so I don't worry too much about not having enough juice.

A starting battery (could be a starter battery or a dual purpose battery) plus a deep cycle battery as a "house" battery to run electronics and whatnot might be ideal, but I've decided to replace my start battery every 3-4 years and move the old start battery to my house battery, so dual purpose batteries like the Costco or Sam's Club ones suit me well.

[Krob1114]

We're in a 2019 R3, so I'm very interested in this thread. All the boats we've owned have had Interstate batteries and we've had no problems. Due to the age of our boat, I'm looking at a portable charged unit to carry on the boat. Then I'll probably try to put the exact battery Cobalt put in when it was new when it comes time to change.

In case my thought process is flawed, any negative thoughts on this would be appreciated.

[jhnmdahl]

Then I'll probably try to put the exact battery Cobalt put in when it was new when it comes time to change.

The local Cobalt dealer here mentioned that Cobalt themselves don't put batteries in the boat - it's part of the dealer prep before delivery, so the battery brand may be different for each Cobalt dealer. Mine was Interstate, but I've heard of a variety of others out there too.