electrics and deep cycle batteries

[the local angler]

hello all i was going to make a serious attempt to get in some boating this year and was wondering about electric trolling motors and the deep cycle batteries that run them. i have a 37lb thrust but no battery yet. i am going to pic one up tomorrow and was wondering what kinda run time do you get obviously varying with different battery sizes,the boat is your typical car topper tinny?the odd time i may have a fish finder electronic on board too.

[pikergolf]

It depends on the efficiency of your motor and the size and weight of your boat. I try to never run my motor wide open, and with a 12ft. very slippery fibre glass boat, I could run close to open about 40 min. and troll for about four hr's.

Buy the biggest battery you can find, and I would look into a motor cycle size one for the depth finder. I get about 12 hr's. run time on mine out of a little gel cell.

[the local angler]

that's great info thanks. my trolling motor is a new duramax drifter 1. i only bought it cause it was cheap and affordable. haven't heard much about this trolling motor even though i would have preferred a minn kota.

[the local angler]

very cool jet thanks now i understand it more and get a better visual.

[EZM]

What Jet says is a pretty good rule of thumb ..... but you will never get that efficiency of power unless you are in the lab.

AH (amp hours) are measured at a discharge cycle time of 20 hours in the lab in temperature controlled environments with a steady draw of power. This is the prescribed rating standard used in the industry.

Keep in mind - the lab is a controlled "perfect" environment and manufacturers of batteries will want to rate their products as high as possible so they control the variables carefully.

Anytime the temperature isn't ideal, you will loose efficiency (like cold weather as an example on a car battery)

There is also the Peukart effect ( meaning rapid discharge) - if your appliance (in this case your motor) is consuming the power in the battery more rapidly (in a period of less than the standard prescribed 20 hour discharge method used to rate batteries) it also looses efficiency.

This also applies if the draw is not "steady" stop and re-starts on a motor are inefficient and suck more energy.

Having said all of that - I'd say, for the average guy - your battery life will fall somewhere between 60%-80% of the above rule of thumb.

So I'd suggest - in the above example you can realistically expect something like 6-8 hours of use at best. You certainly won't get 10 hours out of it. You can be 100% sure of that.

All in All - Jet's example is a good way to try and gauge what size battery you might need - just knock off 20%-40% of the power for real life operating conditions.

[TROLLER]

If you don't want to shell out the big bucks for a gel battery buy the largest deep cycle they sell at Costco.

[the local angler]

thats awsome info guys thanks and costco i didn't even think of that. for me the use would be stop and go between spots and all so i was hoping to find one that can last for at least an 8 hour day if possible cause i fish really long hours like 8 to 14 at the most. most lakes that i fish for trout only allow electrics while the lakes that do allow my outboard is currently closed right now so i am just dying to get the boat out like most of you out there. my battery shopping got rescheduled as i had another appointment to go to.

[Peterupnorth]

I did same as Troller. bought a large deep cycle at Costco.
That was at least 5 years ago. Use it to power band saw sharpeners, boost vehicles all winter, etc.
Then throw it in the 12 foot aluminum boat, run the motor and fish finder.
I've done 3 days fishing before I notice it needing charging.
I only troll on low speed, sometimes on second speed.

[dwedmon]

X2 on the Costco batteries. Bought my deep cycle there and have no issues with it.

Last year they also had a version that used AGM technology, they were a lot more expensive but are supposed to perform much better. Has anyone tried the AGM batteries out?

[EZM]

X2 on the Costco batteries. Bought my deep cycle there and have no issues with it.

Last year they also had a version that used AGM technology, they were a lot more expensive but are supposed to perform much better. Has anyone tried the AGM batteries out?

My new set up has AGM's ....... they seem to last quite a bit longer .... like another couple hours a day but it's really hard to tell because no two days are the same ..... but I'd say they definitely last longer.

[huntsfurfish]

My new set up has AGM's ....... they seem to last quite a bit longer .... like another couple hours a day but it's really hard to tell because no two days are the same ..... but I'd say they definitely last longer.

EZM what brand did you buy? Have been thinking of going to AGMs as well.

[Deep]

I asked about AGM battery vs Deep cycle to the "Rockys Battery" staff. The price and performance has me convinced to just get a very good quality deep cycle and save a few bucks. My humble opinion...

[the local angler]

care to share? what was the difference between the two? is the difference fairly big or very little to minimal where you won't notice?

[Walleyedude]

After spending the money for Optima blue top AGMs last year, in my opinion it wasn't worth it. I didn't see any real performance gain and certainly not enough to justify the large additional cost. I'll be going back to standard deep cycles this year. I think they offer the best value.

[the local angler]

oh ok i get it now the AGMs are what we call the off road batteries for off road trucks. well seeing that i am not that high tech and all i think my choice will be one or two of those costco deep cycle batteries.

[jwelds191]

What Jet says is a pretty good rule of thumb ..... but you will never get that efficiency of power unless you are in the lab.

AH (amp hours) are measured at a discharge cycle time of 20 hours in the lab in temperature controlled environments with a steady draw of power. This is the prescribed rating standard used in the industry.

Keep in mind - the lab is a controlled "perfect" environment and manufacturers of batteries will want to rate their products as high as possible so they control the variables carefully.

Anytime the temperature isn't ideal, you will loose efficiency (like cold weather as an example on a car battery)

There is also the Peukart effect ( meaning rapid discharge) - if your appliance (in this case your motor) is consuming the power in the battery more rapidly (in a period of less than the standard prescribed 20 hour discharge method used to rate batteries) it also looses efficiency.

This also applies if the draw is not "steady" stop and re-starts on a motor are inefficient and suck more energy.

Having said all of that - I'd say, for the average guy - your battery life will fall somewhere between 60%-80% of the above rule of thumb.

So I'd suggest - in the above example you can realistically expect something like 6-8 hours of use at best. You certainly won't get 10 hours out of it. You can be 100% sure of that.

All in All - Jet's example is a good way to try and gauge what size battery you might need - just knock off 20%-40% of the power for real life operating conditions.

Does anyone have information on good, affordable solar chargers for marine deep cycle batteries?! I go to maligne yearly in my 16 footer with 2 guys and alot of gear, and 8 batteries. So an extra 500 lbs of cargo I'm assuming...I'd like to cut that down to 2-3 batteries and just charge the others as I'm trolling with 1. Help and direction would be most appreciated!

[jwelds191]

Solar technology isn't there yet. To charge a battery that's big enough to effectively troll with would take about 4 days to 1 week
at our location in the world and that's assuming good weather. Also you'd
need a large panel and panels are expensive.

You could go multiple panels. I.e. 4 panels may do it in 1-2 days, but panels are big and bulky and at around $250 a piece, it's expensive and a lot of bulk to carry in (carrying in large batteries already charged will likely be easier and cheaper).

Another option would be a generator to charge the batteries, but that's not too easy to carry in either.

A temporary windmill would also be another impracticle solution, although if you had wind you could get enough current to charge a battery in a day.

Hi Jet,

thank you for your information. I'm glad to get some insight on this forum.

I probably should have been a bit clearer in my original post.

I have seen fishermen on maligne lake bring solar panels and have their battery charging on shore while they troll with another battery attached to their electric motor. At the end of the day or when battery power runs low, they switch and the other battery (assumably anyways) is at full power and away they go. I think I came across as I wanted to charge my battery/motor with solar panels WHILE I fish, which is not what I meant. I meant to have them charging idly on shore with a powerful enough solar panel to charge them in a day's sun. Is this possible, and if so what panels would you recommend?

Thanks again and in advance of your answer.

[EZM]

EZM what brand did you buy? Have been thinking of going to AGMs as well.

Trojan ..........

http://www.trojanbattery.com/product/overdrive-agm-31/

The only issue is they weigh almost twice as much (or seem to) as the other batteries .... but they last longer ..... They are also a inch or so longer but still fit in the trays.

[Red Bullets]

Can't say much on deep cycle batteries and such but wondering if anyone has used a rheostat inline with the battery?
An older fellow (electrician by trade) I used to fish with had a rheosatat inline in the positive battery wire. He would have the battery hooked up and turn down the juice? with the rheostat. We could get a few more hours of life out of the battery. I think a rheostat is really cheap too. He had a nice trolling motor too.

Anyone have any experience with rheostats and electric trolling motors?

Might be something to look into to extend battery life..

[the local angler]

with the solar panels its not like a regular battery charger its more like a trickle charge right? i was also thinking this getting a solar panel so it would trickle charge while fishing. a small generator sounds like a great idea charging on the boat.

[EZM]

As Jet just pointed out .... there is no magic bullet for charging on board using a solar source or using your alternator from your main engine ..... it just isn't practical when you can pick up a decent deep cycle back up battery for $100.

You can keep it on shore or wire them up in parallel and keep them on board.

[Dan Foss]

After spending the money for Optima blue top AGMs last year, in my opinion it wasn't worth it. I didn't see any real performance gain and certainly not enough to justify the large additional cost. I'll be going back to standard deep cycles this year. I think they offer the best value.

I have been debating this exact things for the boat this year. I was all convinced on AGMs but when I did the math on them I was not impressed with their capacity. I have decided to go with a trojan battery that is stacked a little taller, gives 150Ah @20hour rate (7.5 amp drain). Biggest capacity wet cell I can find. I figured even if I burn through the wet cell a bit quicker than an AGM, i can buy two for the price of one

[Dan Foss]

I am glad jet did the math... cause reading through the thread I was considering posting the math but.... i hate math... I have looked at solar before and realized it is not even remotely feasible once i did the math.

If battery drain is that big an issue (for most its not unless they are going multiple days on lakes with no access to power overnight). The best investment you can make instead of batteries is a small honda generator. They used to make them in a 700w, but now i think the min is 1000w. it is only very slightly bigger than a group 31 battery. So instead of buying 2/3 extra batteries that take up room and weight etc. this little guy can be running in the boat, and you can cut down on the number of batteries you need. I do know a gentleman who has one in his boat and uses it quite often. Plus a handy unit for camping

http://powerequipment.honda.com/generators/models/eu1000i

[pikergolf]

I was thinking the same thing about the law, but if it is on a gas engine lake seems like a nice option to a gas kicker. Cheaper, can be run slower, and finer speed control. Interesting option.

[rco320]

Just starting to look into this myself. We bought a hybrid trailer, biggest we could fit behind our garage and a few inches matter. Not much room on the outside for propane tanks or batteries ... One of each can fit between the jack and the front of the trailer. Anyways, after our first trip out, we thought it would be nice to get more battery capacity, we'd like to be able to spend more time on unpowered sites or crown land without bringing a generator.

I'm looking at AGMs ... bit more expensive, but they are supposed to be safe for use in occupied spaces where the more economical deep cycles won't be. It'd still put them in a storage bay with a bit of extra venting. This seems to be the only way I can carry extra batteries on the trailer.

If solar is an option (ie an RV or trailer nearby) ... there is a place out of Ontario on EBAY that has a 200W 12V kit with 2 panels and a charge controller for $375 with free shipping. I'm thinking of ordering today. The suitcase/portable types are about twice as much.

200W of solar should recharge a 100AH battery in half a day. With our long summers days, it should be pretty decent on even cloudy days if you can leave it all day.

[EZM]

Agreed - the rated output is far far less then what you would expect to absorb into your battery ..... my neighbor bought the high end polysomethingorother panels (apparently the good ones) for his RV expecting to get a certain level of of performance.

These high end panels, along with controllers, cables, etc... looked great. The panels, 4 of them, were about the size of a 1/3 sheet of plywood, and yielded about a third of what he expected, AND, too boot, it was hot, sunny, mid summer.

He spent $900-$1000 and was quite disappointed in the solar - so I'd say do some real life searching on other forums before you drop bucks on something that isn't going to give you what you are expecting.

[Speckle55]

I use 180 min reserve or better which is a R28 or bigger to R32:sSig_cool2:

I need 2 battery's on Maligne Lake per day with a car topper in bad weather

4 nights 5 days = 10 battery's rule of thumb:happy0034:

I have a 12 ft and a 14ft Alum sometimes rope together down loaded Fisherman's Bay(8 1/2) then empty fishing for 3 days and last day home loaded

most battery's will get you trolling with a Mini Kota 55# 12 hrs :test:

if I run it wide open I get 1 hr = 4 miles ..that's loaded

I get 7 to 10 years per battery and charge them every 3 months or more:47b20s0:

I have used Cat battery's at 410 min reserve but they are to heavy now for this old guy:confused0024:

after a few years watch the water level in batteries

Food for Thought

David:)

David:)

[rco320]

thanks Jet, that's good info, both on the AGM and solar.... I'll do a bit more research before committing.