trolling motors and batteries

[pizzaman]

So I was given an old motor this spring and rigged up my kayak with it. Has been a blast cruising around for planter trout in the local lakes. This thing is really old like at least 30 years and I bought the cheapest deep cycle battery I could find locally to test it out. My question is how much have trolling motors improved over the years? It's on a kayak so even this old guy pushes it around pretty good. In fact if conditions are calm with no wind on low speed it moves a little fast for trolling. I get a solid 2 hours per charge on this setup. Would a newer motor be that much more efficient or would a better battery be a better investment?

[BentRod]

I have a Minn Kota Endura 50lb thrust paired with a Costco group 27 RV battery. It'll push my 12' aluminum boat around the lake all day at low power. If I run at high speed I'd probably get a few hours out of it due to the higher draw at full power. It's got 5 forward speeds and 3 reverse.
You should be able to look up online the amp draw of the make and model of your motor (if not listed on the motor itself). Between that and the amp.hour rating on your battery, you should be able to calculate how long it'll run off the fully charged battery. I'd guess that more modern motors are more efficient, but don't have any experience with the older ones. Mine is an early 2000s vintage.

[Bustinbeats]

The weedless wedge style prop was a great advancement, but that was 20+ years ago. Infinitely variable speed control and more efficient battery use were a couple of other nice steps forward...but at the end of the day, the old school motors still move the boat around ok and get the job done. Cleaning the weeds out of those old style props was a bother.. I don't miss that chore.

Take care of that battery and it should last for years. Always charge it after use and store it with a 100% charge on it , but avoid overcharging. Since batteries tend to self-discharge during long periods of storage, hitting it with a the charger every few weeks for an hour or two is a great idea during the off-season, or better yet, buy a float type automatic charger (Battery Tender) and just leave it hooked up all the time. The automatic charger will turn itself on and off as required to maintain the battery at a 100% charge, which is very important if you want a good long life out of it. Some batteries require distilled water to be added to them occasionally, others are sealed. Figure out which kind you have and pay attention to that, as well.

[hewesfisher]

Couple comments on deep cycle batteries. Most important, unless post arrangement and case size are an issue, forget buying a battery by "group" numbers. They have absolutely nothing to do with the most important spec on a battery - capacity. If you want the best bang for buck, you need to compare battery capacity not case size/group numbers. When you look at capacity, the most important spec is called "Reserve Capacity". That tells you how many minutes that battery will support a given load, the higher the reserve capacity, the longer it will perform for your trolling motor.

When using a wet cell battery you must keep it charged and electrolyte topped off. The so-called "maintenance free" RV/deep cycle batteries are not, they are simply lead acid batteries with smooth caps. You still need to remove the cap and ensure electrolyte level is correct. As mentioned, when you do need to add water, never use tap water, distilled water only.

As bustinbeats said, you would do well to get a battery maintainer for longer between use periods. It won't charge your battery overnight, but it will keep your battery near top performance. NOCO makes a really nice one. I have three of them to maintain my RV (2) and tractor (1) batteries and highly recommend them - less than $40 too.

For overnight charging, buy a 10 - 15amp smart charger. The nice thing about smart chargers is they adjust charge profile to the battery without you having to make decisions as to type. They also do not require any user involvement, connect and walk away. The better ones also have a desulfate mode for wet cell batteries. NOCO's Genius series do this.

In order to know how long any battery will last, you need to know what amp load you are placing on the battery. Older motors were definitely less efficient and noisy (electrically speaking) too. Once you determine the load, then you can match a battery that will meet the demand.

[pizzaman]

Good info! Thanks for the replies. One more question. Currently I have the battery sitting behind the seat which makes the Stern ride a little low. I was thinking of stashing the battery up front and even ran some wires to do it but I am having second thoughts. I am concerned that there isn't enough ventilation and I would be risking an explosion or fire and being as it's right in front of my legs I'm thinking this might not be such a safe idea. I know there is some risk when charging a battery so I am assuming the battery under load would also outgas?

[Bodofish]

Good info! Thanks for the replies. One more question. Currently I have the battery sitting behind the seat which makes the Stern ride a little low. I was thinking of stashing the battery up front and even ran some wires to do it but I am having second thoughts. I am concerned that there isn't enough ventilation and I would be risking an explosion or fire and being as it's right in front of my legs I'm thinking this might not be such a safe idea. I know there is some risk when charging a battery so I am assuming the battery under load would also outgas?

As a general rule for a planning hull the batteries are put as close to the stern as possible for one reason. That's to save them from the pounding of having them up front.

[hewesfisher]

Good info! Thanks for the replies. One more question. Currently I have the battery sitting behind the seat which makes the Stern ride a little low. I was thinking of stashing the battery up front and even ran some wires to do it but I am having second thoughts. I am concerned that there isn't enough ventilation and I would be risking an explosion or fire and being as it's right in front of my legs I'm thinking this might not be such a safe idea. I know there is some risk when charging a battery so I am assuming the battery under load would also outgas?

As a general rule for a planning hull the batteries are put as close to the stern as possible for one reason. That's to save them from the pounding of having them up front.

Probably not going to matter much in his kayak. I thought about his last question regarding placement, but I don't know a thing about kayaks. Surprised there's even room for a battery.

[KIDKOKANEE]

Ive got a small trolling motor newer Min Kota and paired it with a NAPA bought Marine Battery one of those that look like a six pack beer and put the battery in a min kota battery case the one that has the charging indicater and two plug ins , Works great have taken my battery has carry straps with me on several fishing trips other people boats for a back up as they have problems after a few hours ! only problem I have is the Weight its so damn heavy !! to carry takes both hads etc like two men and a boy you know!! Anyone know if a light weight battery out there thats a good one thats hold a charge this one you dont have to fill up etc and long warranty works great only really heavy I have a smaller boat and battery is mobile!!?? appreciate if anyone out there knows of such a battery?? (LIGHT WEIGHT AND HOLDS A CHARGE TO BE PLACED IN THE MIN KOTA CARRYING CASE!! One of my fishing partners even got a solar panel for his battery as he has a larger boat and this big battery looks like a semi battery only its a marine battery! Well appreciate any productive imput on my heavy battery trying to lightn up my load just purchased a new 2012 Suzuki 4 hp today at Auburn Sports andMarine Got the Tent Sale Memorial Weekend price and it 4 Stroke wont need a gas tank and weights 55 pounds I swear that battery for my trolling motor weight same as my new gas motor!! Thanks guys!! FISH ON!! wish me and a fishing buddy kokanee king we going to skykomish tomorrow sunday to hook what bites!!!

[Bodofish]

Light weight and long lasting just don't go together when talking lead acid batteries.

[hewesfisher]

Well, if you really want to save weight and still have the performance of a 100ah battery, you could buy a lithium ion battery but you better really want to save some weight.

http://www.lithiumion-batteries.com/pro ... attery.php" onclick="window.open(this.href);return false;

[MotoBoat]

Couple comments on deep cycle batteries. Most important, unless post arrangement and case size are an issue, forget buying a battery by "group" numbers. They have absolutely nothing to do with the most important spec on a battery - capacity. If you want the best bang for buck, you need to compare battery capacity not case size/group numbers. When you look at capacity, the most important spec is called "Reserve Capacity". That tells you how many minutes that battery will support a given load, the higher the reserve capacity, the longer it will perform for your trolling motor.

Phil, has added some interesting and valuable info, targeting the technical aspects of a battery. That technical data printed on the label. Has had me scratching my nogin, and saying huh!

CCa, reserve capacity, group size, amp hours. After replacing batteries for the first or second time, group size becomes fairly straight forward. But CCA, and reserve capacity has been a long standing brain strain. Reserve capacity has been unlocked. What does Cold Cranking Amps refer too?

Touching again on group size. How is the same cca, and reserve capacity (group size) squeezed into a smaller case?

[Bodofish]

Plate configuration and electrolyte. Cold cranking amps don't really mean much when discussing a deep cycle battery. They're totally a hold over from the starter batteries used in cars. It gives you an idea or comparison of sharp heavy amp draw like say from a starter motor starting them main.

[hewesfisher]

Plate configuration and electrolyte. Cold cranking amps don't really mean much when discussing a deep cycle battery. They're totally a hold over from the starter batteries used in cars. It gives you an idea or comparison of sharp heavy amp draw like say from a starter motor starting them main.

Exactly.

CCA is useless in a pure deep cycle application where the most important characteristic is how long the battery will support a given load. For trolling motor use, that element is reserve capacity, which most people completely overlook when buying a battery for use in a deep cycle application. Most people simply buy a battery based on group size, not it's performance characteristics. Sort of like buying light bulbs because they fit the socket and not paying attention to how many lumens they produce.

CCA does become relevant, however, in two cases when used on a boat. One, when a battery is used purely as a start battery and the motor requires a specific CCA to operate, and the other, when a dual purpose battery is used as a start battery and also for some parasitic load (trolling motor, sonar, radio, etc.) when the main motor is off. In both instances CCA is an element that must be considered in battery selection. IMO, group size should only enter the battery buying decision process when one is restricted to a specific size or terminal configuration. Even then, a comparison should be made between batteries of the same group size to get the best bang for buck, warranty, reliability, etc.

[SoDakboy]

I'm not gonna remember any of this stuff when I finally buy a trolling motor battery. So you people better still be around when that happens...

[DonGorsegner]

One thing that I have learned with deep cycle batteries is to have a three stage charger. It makes a huge difference in how long your battery will last and perform. I picked up a nice charger for 65 bucks and it has made a dramatic difference in battery reliability, I can fish for about 8 hours and be down to 40 percent charge. Yep the charger gives feed back on the charge percentage. A friend who designs solar systems turned me one to the three stage chargers, aside from the trolling motor I also run a fish finder in my little 12 foot boat. Also quite handy

Don