Batteries in boat, dampening solutions???

[mkthbk]

I have 3 batteries on my 16' Alum Tracker and am in the middle a complete redecking project.

When hauling my boat it seems to me my batteries are taking some jolts. I had the idea of of providing them more dampening buy adding a piece of say 1/4 plywood and maybe something like a teenis ball cut in half and put a 1/2 under each corner. Or mabe 4 small but soft rubber balls. I believe I read it's not good for your batteries to be bounced.

Yea the trailer has leaf springs but occasionally it does seem to take a hit now and then.

Anybody have any input?

[Fishing Rhino]

I don't know where the batteries are, but the best place is at the stern.  It "bounces" less than the bow, which rises and falls more than any other part of the boat.  

The further back in a boat, the less shock from slamming the waves.  If you've ridden near the bow and the stern in rough water, you know there is a considerable difference.

If they make gel cell batteries for your application, consider them.  They are generally more expensive, but in most applications they are superior to the standard batteries.

For cushioning, I suggest you look into industrial floor mats used to cushion concrete floors.  You need something that will stand up to the acidic fumes discharged from battery vents.

You could also consider using silicone under the battery.  Get some tubes of silicone from a hardware store or builders supply store.  Take a couple of pieces of plywood larger than the pad you need.  Put a piece of wax paper on one and spread the silicone (thicker than you need) on the wax paper.  Put a spacer the thickness you need at each corner of the plywood.  Place another sheet of wax paper on the silicone, then the second piece of plywood, then put a weight on the plywood to press the silicone to the thickness you need.  You could probably press it down and leave it at that.  In its gel state it won't spring back.

Allow it to sit for a couple of days or more to set up.  Using a metal straight edge (a builders' square is ideal), trim the pad to size with a sharp utility knife.

The thicker the pad, the longer it will take to cure.  I've used this technique to make a silicone gasket between my truck cap and pickup body.  Works better than any of the foam or rubber tapes that are used by the places that sell and install truck caps.  After several years, the silicone remained in place.  The tape gasket always works out after a few years, or less.

It will separate easily, though some of the wax paper might end up on the silicone.  

Unless I'm mistaken, cured silicone is about impervious to anything.

Be sure to use a plywood of sufficient thickness that will not distort when you place the weight on it.

Silicone withstands abusive environments including heat very well.  It is used to provide a seal on many parts of racing engines, withstanding serious heat and vibrations while maintaing a working seal between engine parts.

Been awhile, over ten years ago, since I bought batteries for my lobsterboat.  But, I used sealed, gel cell batteries.  They had no vents.  

Those batteries are monsters.  It takes two men to handle one safely.  I believe the size was 8D.  A twelve volt battery weighed in at nearly 200 pounds.  My boat took three of them, two for cranking the big diesel and another to power the electronics and lighting.

[Ann-Marie]

So long as the bouncing is not damaging the boat structure it will not hurt the battery.

[Fishing Rhino]

So long as the bouncing is not damaging the boat structure it will not hurt the battery.

I'm not so sure about that. I'd like to see a source for that info. The following is what I have believed to be the case for some time.

Independent industry studies prove that the most common cause for battery failure is vibration and mechanical shock. Each year millions of dollars are needlessly spent on replacement batteries because consumers unwittingly mount their batteries on hard surfaces that do not absorb the jarring effects of daily use, often leading to sudden and premature failure of the battery. Vibration causes active plate material to loosen and fall to the bottom of the battery case and can break inter-cell welds and grids. Loss of material decreases the life of the battery and could also cause shorts.

Simply put, battery life is cut far short simply by vibration and mechanical shock.

Durability: Some battery designs are simply more durable than others are. They are more forgiving in abusive conditions, i.e.; they are less susceptible to vibration and shock damage

Gel Batteries

A gel battery (also known as a "gel cell") is a sealed, valve regulated lead-acid battery and has a gel electrolyte. Unlike flooded lead-acid (wet cell) batteries, these batteries do not need to be kept upright. Gel cells virtually eliminate evaporation of the electrolyte, spillage (and subsequent corrosion issues) common to the flooded lead acid battery, and boast greater resistance to extreme temperatures, shock, and vibration. As a result, they are often used in automobiles, boats, aircraft, and other motorized vehicles.

I came up with these on a quick internet search. It seems some may be more durable than others and may be "LESS SUSCEPTIBLE" to vibration and shock damage.

It occurs to me that anything that can be done to reduce the pounding from a boat driving through rough water is advisable and desirable.

[Fishing Rhino]

I have 3 batteries on my 16' Alum Tracker and am in the middle a complete redecking project.

When hauling my boat it seems to me my batteries are taking some jolts. I had the idea of of providing them more dampening buy adding a piece of say 1/4 plywood and maybe something like a teenis ball cut in half and put a 1/2 under each corner. Or mabe 4 small but soft rubber balls. I believe I read it's not good for your batteries to be bounced.

Yea the trailer has leaf springs but occasionally it does seem to take a hit now and then.

Anybody have any input?

Here's something from Cabela's.  Probably cheaper than the silicone mat I suggested, and more in line with your tennis ball idea.  Of course, you could always take your tennis ball halves and fill them with silicone.  It would be better than the mat since it allows for better battery cooling.

http://www.cabelas.com/link-12/product/0031072017559a.shtml

[done]

Good ideas! I think I may have to go with the silicon filled tennis ball idea. I keep mine in the middle of the boat, helps it plane out more.

And with a gut like mine, I need all the help I can get.

[Wayne P.]

Marine batteries are built with the jolting in mind for on the water and trailering. Your batteries should be held down by clamps or straps so they will not bounce from their position and move with the boat hull. Adding shock absorbers may be a good idea, but not necessary. Adding a thick soft padding under the battey may cause it to move around even more than just sitting on a hard surface.

[mkthbk]

Thanks for everyones response the item from Cabellas looks great in design and in price.

[surfer]

While technically bouncing is bad for batteries I have never actually heard of anyone having a bouncing or jarring related battery failure.  

Why fix something that aint broke?

[Fishing Rhino]

While technically bouncing is bad for batteries I have never actually heard of anyone having a bouncing or jarring related battery failure.

Why fix something that aint broke?

Marine batteries are more resistant to damage from bouncing, vibration and jarring, but they are not impervious to it.  It wouldn't manifest itself by sudden battery failure.  It shortens the life of the battery.  It is something that happens gradually over time.

If cushioning extends the life of the battery and protects it from the shock of bouncing and jarring, why not do it?

[surfer]

I was under the impression bouncing and jarring failures would be sudden such as a plate breaking off inside the battery or the casing cracking.  How would it cause gradual weakening?

[NBR]

Thousands and thousands of boats with out special dampening for the batteries and no outcry for improvement I would think it was not a big deal.

[Fishing Rhino]

I was under the impression bouncing and jarring failures would be sudden such as a plate breaking off inside the battery or the casing cracking. How would it cause gradual weakening?

The vibration and jarring cause small particles of the plate material to fall from the plate.  They accumulate in the space at the bottom of the cell.  Once they reach the cell, they short that cell out.  It may start as a trickle, and drain that cell over a few days.

Most of us have had a battery that will restart a car a short time after you turn it off.  Leave it overnight and it won't crank the car.  That is because the cell loses its charge the same as if you had a small light draining its power.

When I was a kid, there were several auto shops in the area that used to reclaim old batteries by rebuilding them.  They cut the top open, remove the packages of plates, flush all the lead sediment from the bottom of the battery, then put 'em back together, sealing them with a tar like substance.

The batteries were good for a few more months.  They would never be like original because the plates had lost some of their lead.  It was a thriving business back in the 40s and 50s.  

Those were the days when you kept patching things up to get more life out of them.  My mother used to darn our socks.  When a sock had a hole, she'd take something like fine yarn and fill in the gap.

Folks saved jelly jars, baby food jars, etc.  They had to be good for something.  My dad never threw a nail, screw, nut or bolt away.  He'd toss 'em in a can, and when he had time, he'd sort 'em out.

He'd spend two hours looking for a nut that he could have purchased at the hardware store a half mile for home for a few cents.  Those were different times.