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Are your Boat Batteries Safe?


The advent of another fishing/boating season is a lot closer than you might think, but that doesn’t mean the impatience that comes with waiting gets easier to deal with. We should by now be armed with the knowledge that we have gone about checking rods, reels, terminal tackle, etc., and looking forwards to have another successful fishing season. But, let’s see what kind of captain or mate you measure up to be when it comes to battery knowledge for your boat. Marine and boat batteries are one of the most important accessories for today’s modern marine electronics, and for fishing and boating equipment in particular.

With today’s fishing boats being more complex than ever, this is an area that probably gets the least attention and should probably get the most. Things like GPS, sonar, downriggers, electric trolling motors, livewells, bait tanks, etc., are all part of the modern fisherman’s necessary equipment. If you are like me, you have multiple devices on board your boat for your fishing convenience. All of these modern electronics can all take a toll on boat batteries. If you own a larger craft, radar and autopilots and more can put a toll on your vessels electronic power source. Not to mention lights, horns, and everything else that might be available to the modern boater.

Just how smart are you when it comes to the batteries in your boat? Below is a little true or false test that you can take to see if you really are “battery” oriented, or… if you are going to be one of those boaters/fishermen in the middle of nowhere, that will break down because of battery failure. Cheating won’t help you here!

True or false: Storing your batteries on a concrete floor will discharge or destroy them.
According to Bill Darden of Boat & Motor Dealer, this suggestion was born many, many, years ago when battery power was pretty new and batteries were built in porous tar-lined wooden boxes and then indeed, they would transfer power to the concrete below them. Now with the modern advancement of hard rubbers and polypropylene materials, this is seldom a problem unless of course your batteries are stored on an extremely cold surface. Then the natural discharging abilities of cold become a factor. I still keep my batteries on a piece of wood, but old habits die hard. The real answer of course is false.

True or false: A battery will not lose its charge while being stored for the winter or off-season.
Batteries have a natural discharge or “leakage” rate anywhere from one percent per month to as much as twenty-five percent per month, depending on the temperature surrounding the battery or batteries. Over time, stored batteries that are not cared for properly can become sulfated and eventually become fully discharged. And here is a surprise for you; the sulfating process is more aggressive at higher temperatures than at lower temperatures. For example, batteries stored in temperatures around 95 degrees Fahrenheit will discharge twice as fast as batteries stored at 75 degrees Fahrenheit, and absolute cold isn’t much better. Keeping your batteries in a “comfortable” environment will go a long way to preserving the battery’s charge and its useful life. Removing the batteries from your boat and then leaving them in a cold garage will do little else than create unnecessary work for you, if they are not put up in a warm dry location. The answer is false.

True or false: Maintenance free batteries never need any maintenance.
If you live in a temperate climate, problems with maintenance free batteries are almost non-existent. Almost being the key word here. They can and will eventually need some type of professional care, especially if you live in a very hot climate. Most times the problems are chalked up to a “bad” battery and will be replaced. As a matter of fact, knowledgeable marine service repair shops in hotter climates will recommend non-sealed types of batteries so that evaporated water in the electrolyte can be replaced more readily and more often. Answer, false.

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True or false: Using additives or aspirins in your older, half worn out batteries is a good practice and will rejuvenate your old batteries.
These old home remedies might give you some short-term benefits, but over the long haul more damage than improvement will result. The same is true with pulse chargers for these sulfated batteries. There is no positive proof that pulse chargers convey any more benefit to your uncharged batteries than normal battery chargers will. These two subjects remain highly controversial amongst many do-it- yourselfers, but true battery professionals say it’s a no-no. False.

True or false: Marine lead-acid batteries have a memory.
This misconception came to light with the first generation Ni-cad batteries so popular in cell phones, pagers etc. This however has nothing whatsoever to do with lead-acid batteries. But, be aware that consistently undercharging lead acid batteries can cause them to have a much shorter life. False again!

True or false: I need to clean the terminal posts on my boat batteries every season even if they are kept tight.
It is a good practice to remove all of the terminals and electronics connected to your boats batteries and clean the posts either with a wire brush, sand paper, or a special tool made specifically for cleaning battery posts and terminals, at least once, if not twice during the boating season. No matter how tightly you keep the terminals of your battery connected, the constant on-off of electronics coupled with the naturally damp environment and continuous electric currents being applied will eventually cause a non-conductive corrosive buildup to form on battery posts leading to a non-charging, dead battery situation. The answer here of course, is true.

True or false: Last but by no means least, batteries, marine or otherwise, will not explode if handled improperly while jumping or charging.
I’m not even going to fool around here, False! False! False! I have seen first hand what can happen when a charger or jumper cables are applied to a lead-acid battery improperly, it’s not pretty. Pieces of battery become shrapnel and battery acid becomes a stinging, burning bath. Injuring at the least, the skin on your face and hands; at the worst, your eyes! This is something you do not want to fool around with if you are not sure of what you are doing. A battery can explode through the ignition of hydrogen and oxygen gases created by sparks while connecting chargers or jumper cables improperly. If you are lucky, many times you will just “pop” the caps off of the individual cells during this process. If you are not, well, although few, some deaths have been recorded under these circumstances. Be safe, if you don’t know what you are doing, get professional help, or you will need it in more than one way!

There you have it. If you keep your batteries cleaned, charged, and stored properly and “stored properly” doesn’t mean in the boat in storage. When batteries are to be out of service for any length of time they should be removed from the boat and stored in a warm, if possible, dry place, and use the wooden board; I still do. Do these few things and you will go a long way to having an enjoyable breakdown free fishing/boating season in the coming summer months. Answer yourself truthfully, how did you score? If your answer was just so, so, go back and read again, right after you visit the fishing and outdoor shows. Maybe new batteries will come with a new boat.

If you take care of your batteries properly, you won’t wind up in this predicament like these two guys. Photo: Herman Kunz



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Herman Kunz

Herman Kunz is a freelance writer specializing in all types of hunting, freshwater fishing and other outdoor-related activities, including seminar speaking and promotions. Kunz is on the field advisory staffs of Rapala, Flambeau tackle systems and Storm Lures, and may be reached at 618-599-2400.

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