Home Forums Hunting & Shooting Hunter's Campfire Questions on Marine Batteries

They're good for testing charged starting batteries, but won't help ideally with cycling batteries, which need cycled for a proper test.

You can also use them to detect a bad cell, but hydrometers are much safer. If one cell has 25-50 points variance, dont bother charging. It may kaboom if you do.
With a load tester, any cell that percolates rapidly and emits gas is toast as well, but be aware that gas is highly flammable.

Newb boater here. And despite my profession, I'm a minimal maintenance guy on recreational stuff.

Are you saying that batteries shouldn't be kept in summer temps over 70 degrees? Common here to not see night time temps below 70 in summer.

Sulfate internally???

Surface charge????

Odyssey battery sized for your needs with a pro charger/dual pro battery charger. When not in use keep charger plugged in, going on 10 years with that set up in my boat. Cry once

Why is a hundred dollar battery a cheap battery?

The only difference between starting and marine is the connection posts. Marine will have more options, bolts, tab....

Crow hunter,

I like your set-up, and I'm personally geared towards redundancy on any critical system.

Question...
Could that battery selector switch, or something similar be used to connect to a trolling motor battery for an emergency start. Would doing so complicate the charging system?
Also, would the 1&2 switch position work with different style batteries? (deep cycle and starting)

My boat is small, at 16'8", and I'm running a single battery for the 55 lb thrust trolling motor

In short, that $400 battery is a gel battery. They don't break as easy as a traditional battery, but it's pretty tough to break a traditional battery.

Extra batteries are never a bad thing, but weight becomes an issue on small boats.

I use Interstate (4) on my personal boat.

Optima on the dozen, or so, boats I drive on my other job. (I don't have to buy them.)

I keep two batteries in my boat. I’m special, but can’t quite walk on water. I keep the spare charged, run boat on it some.

Skip gel. AGM batts are superior.

I don't do wet batteries anymore. AGM is so much cleaner and corrosive free and no maintenance required.

Same here. 2 Costco batteries get abused during the summer, sit all winter, then put on a charger in the spring. I’m surprised they’ve lasted the 4 or 5 years I’ve had them.

At this rate that $400 batterie better last 20 years.

I have a Walmart marine starting battery (around $90 last time I purchased) in my Ski boat, We typically get about 200 hrs on the clock a season. Every time we board a skier we cut the engine so it gets a lot of starting. The engine is carburatated 408, at 9.6 compression so its not an easy motor to crank. We have a moderate stereo and depth finder in the boat as well.

In the off season I keep 4 batteries, One starting for the ski boat, One starting and two deep cycle for the fishing boat in the basement off the floor and top off the charge every two months. I set a calendar reminder and I can get it done in a day switching between batteries every few hours. I get 5 years or so from the starting batteries. Thats $20 a year for a starting battery, not bad.

If I was on a big lake or the ocean I would definitely have a second isolated starting battery in a boat.

I was told battery acid/fluid if leaked out of battery will dissolve the aluminum in boats. Like lunds.

The bottom of the battery is important as the plates will break down and come into contact.

Interstate batteries have stronger bottoms construction I was told.

Boats are expensive to run.

Lots of options.

I use Deka AGMs, An intimidator cranking battery 775 CCA for my 115 two stroke and two intimidator deep cycle 900 MCA AGMs for trolling motor. They are clean and recharge fast. I charge once a day while staying at my place close to the lake and generally the deep cycles charge up within 3 hours. AGMs are also known to hold a charge for a long time when not being used. I get around 10 years of use.

If I were to go on an extended campout without any electricity available for two weeks or more at Lake Powell, which I used to do, I would get some large 6 volt Trojan golf cart batteries for my trolling motor which last a long long time. I realize that four 6 volt monsters for 24 v would sink some boats but they will go for a month! Recharging them after a trip like that will take 16-20 hrs or more.

I ran three batteries in my flats boat. Two for the electronics and trolling motor and on starting battery. I ran gel batteries. Wasn't no pull starting my motor so I never spared any expense on my batteries. I always figured they go me around and home. I had a few guys I fished with before I got my skiff and they was always having battery issues. If I thought I had a battery going bad I replaced it. Seven years with that skiff and never had to get a jump or tow. I did use it dang near every weekend so I think that helps. If I recall I replaced the OEM batteries after about a year and a half and replaced the gels once about a year before I sold that boat.

I run my trolling motor and FF off two Duracell AGM Deep Cycle Marine and RV Battery. Very hard to beat for $179

I keep my batteries plugged in and charged year around using a Minn Kota Precision Charger.

Mine are group size 31

Minutes at 25 amps: 210

Get the $100 battery and some kind of trickle charger/battery minder. I use a battery tender junior on my boat with a Duracell brand battery from Sam's. When the boat is not on the water keep the battery minder on it all the time, 24-7 365. Batteries will last a very long time.

For redundancy you could spend another $100 or so and get one of those lithium jump starters. They take up little room in a small boat.

Back in the day we would let the boat's battery sit and throw a regular battery charger on it the night before a trip. Batteries would only last a couple of years that way. I got better than 10 years out of my last boat battery that had a battery tender on it.

Wet batteries will discharge quicker as temperatures go up during storage.
As batteries discharge, the plate paste oxidizes. If left discharged the paste oxidation can create enough of a barrier that the chemical reaction from charging cannot take place. In bad cases, it can ruin the battery.

I've had excellent luck with Optima blue top marine batteries

Yes... IMHO.....yes. It's exactly what I have done on our camper..

Only thing I will say is to stay AWAY from the X-2 AGM batteries - site here: https://x2powerbattery.com/ (at about $340 ea) because they will NOT hold a charge.. I've tried three (first two replaced under warranty within the first year each) and the latest one - even with a battery tender on it - failed to hold a charge.. I dropped that POS off at the local auto parts store and bought one of them no-maintenance standard battery (series 31) and saved another $200+ overall. That third battery the original store would not honor any coverage on it.. Lesson learned.

If that's all you plan on running on your boat you answered your own question. Two $100 MARINE batteries linked together through a battery selecter switch will last you three or four years if you maintain them during the winter. I ran the same setup on my boat. The engine, fish graph, autopilot, radar, temp probe, fm radio, down riggers, washdown pump and interior lights were on the main battey. Safety stuff (VHF radio & gps/chart plotter) were hooked up to the spare (isolated) battery. YMMV...