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I am currently using a Mankato 55 kw trolling motor for getting in and out of the slip and for when the Wind God's have all gone to the Bahama's for the rest of the afternoon. In an ordinary setting I use the battery maybe 10 minutes at a time. I generally have to recharge it once during the season, sometimes twice if I forget to turn off the motor for an extended period of time. The only other thing I use it for is the bilge pump but since I have a better cover for the boat and I have patched the leaks in the hull I use that very sparingly. I am using a standard Deep Cycle Marine Battery to operate it. My main issue with the current set up is the battery weights about 450000 lbs at least!! Seriously, It probably weights in the neighborhood of 50 lbs and for a small boat like the Slogger that is a lot of weight to carry in the stern.

I have been looking at the new crop of smaller batteries and those Optima Blue Top batteries. The main issue with those is they cost about half of what I paid for the boat!! Has anyone had any experience with batteries for trolling motors other than the standard automobile sized battery?

Thanks

i'm guessing what you mean by a 'standard sized' battery would be a marine group 24 that holds somewhere around 65 amps.

yes, a group 24 battery will weight about 50 pounds depending on the type (wet let, AGM or gel).

if you see a battery much lighter than this it is not a Group 24, it is a smaller battery (like a U-1) with less amp capacity.

you want a deep cycle marine or RV battery, not a car or starting battery.

have you considered making a long set of battery leads so you can put the battery up near the bow? good place for a battery to sit opposed to the crew.

I have thought about that and may give it a shot. I may be done for this year although the boat is still in the water. We had a foot of snow on the First and the temps are not supposed to get higher than the mid 50's now until next April. I realize for some of you that is almost a heat wave but for this ex Florida boy mid 50's is just this side of blizzard conditions!!

Thanks for the other information. The large battery isn't really a problem except for the weight. I will put it in the bow next time I am at the boat and see what the trim is like.

lustyslogger wrote:I will put it in the bow next time I am at the boat and see what the trim is like.

just to restate don't put at the bow, but near the bow. weight at the ends of a boat can induce hobby-horsing.

wdscobie wrote:

lustyslogger wrote:I will put it in the bow next time I am at the boat and see what the trim is like.

just to restate don't put at the bow, but near the bow. weight at the ends of a boat can induce hobby-horsing.

I guess I will have to tell my wife she can't sit on the bow any more!!!!

(Thank God she doesn't read these forums)

We should never use our wifes as ballast!... (unless we have to and we keep that to ourselves....)

By the description you've given of your use and loading,
I'd move the battery to midships or
consider two, lighter batteries and switch them out each visit so one is always at home on the smart charger.
That way you'd have a much smaller and lighter day use battery that you could leave a board for the bilge pump.
Or, because you don't have enough options already, get yourself a small solar panel and run with one of the smaller batteries amidships.
Good luck.

I have had good experiences with hawker odyssey batteries. In fact when I repower with electric this spring (torqeedo) I will be using their batteries for power

Unfortunately there's not much you'll find that gives 12v for a motor that weighs any less that 50 lbs. Deep Cycle Bats will give better service but will weigh a bit more (more plates).

If you need short bursts to just get out the slip you could try a 12V motorcycle or lawn tractor battery. But you'll get 80% less service between charges than a size 24. Two in parallel would be better and weigh 12 to 15 lbs.

We had two 4D batteries in our C34 for the house bank. They were a treat to get up the companionway (about 130 lbs each).

I would second a lawn mower battery get a jell filled one so you don't have to worry about fumes. Unless you are going a long ways that is all you need.