Battery replacement

[jwm2201]

I have a question on batteries, I have an older boat so it's on the heavy side around 2800 lbs. off the tailor now the trolling motor 90lb thrust a little overkill but it handles the wind very easily only being an 18ft boat. I have been researching the Optima deep cycle batteries in particular the Optima D 34 battery. My question is any other recommendations or preferences out there?

[mikechell]

I deal with marine technicians at work. For the most part, people either love Optima Batteries, or they hate them. The majority, by a small margin, are the haters. Not worth the money, they say, since they don't last any longer than lead/acid batteries.

You DO want Marine deep cycle batteries, though, for running trolling motors and such. They are more suited to complete discharge/charge cycles than cranking batteries.

[Captmikestarrett]

A battery is like a dog.. if you treat it right and charge it right after a trip and top the water off with distilled water every year and never let it sit in the cold of winter without a trickle charge it can last 5-8 years. The dog if taught from a puppy to walk right and heal will be a good also.

Capt Mike

[Captmikestarrett]

Back to batteries and my tin boat needed a set of 27dc deep cycles. Sticker date was 7/11 and I boiled them dry by not adding water before storage. They work but just barely thru a day of guiding. So with my pockets thread bore I decided to replace them with the same cheap Walmart brand. If I had flooded them like I should last fall they would still be good. I once got 10 years out a set of the same cheap battery's.

BOAT = break out another thousand.

Things are looking good for my swamp boat.

Capt Mike

[mikechell]

I have never heard of "boiling a battery dry". Neither has any of the other instructors I've asked about it. If it works for you Mike ... disregard everything below.

The problem with that option is the plates, which are capable of oxidation. Leaving them dry exposes them to the forces of oxygen. Batteries that are bought dry, are also vacuum sealed and capped to prevent oxygen and moisture from getting in there too soon.

Best way to preserve batteries through the storage period is full and fully charged. The discharge cycle creates crystals on the "outflow" plates.
If a battery is stored in the discharged state, the crystal are many and will continue to "grow", feeding on electrolyte.
If the battery is fully charged, there are very few crystals and very little further crystallization can take place.
Oh, and fully charged, the electrolyte will not freeze until well below 0 degrees F. (I've heard it's as low as 77 degrees below freezing.