Nice battery setup for small boats!

[Kim Whitmyre]

My C.G. neighbor is a kayak fisherman, and the other day he was re-wiring his fish finder. Among the stuff spread out while he was working was a Pelican case fitted with a battery:

http://malibuoceansports.net/productcart/pc/catalog/battbox.gif

http://malibuoceansports.net/productcart/pc/catalog/battboxlg.gif

Here's the info:

"A great solution for keeping your battery dry and safe. Avoid electrical shorts, damaged batteries and corrosion issues with this battery box made out of a completely waterproof Pelican case. A Sea Dog deck connector on the side of the box makes for an easy connection and easy installation into your existing wiring. The optional 12 volt 10 amp battery will power a fishfinder, bait tank and running lights for hours. "

Fifty dollars for the case alone, add another twenty dollars for the battery. I'm on it! This will be perfect for led running lights on my cat.

Here's the URL:

Hooked On Kayaks battery setup (http://malibuoceansports.net/productcart/pc/viewPrd.asp?idcategory=9&idproduct=1183)

[Frank Wentzel]

I want to strongly caution you against putting a lead acid battery in a sealed case. Lead acid batteries emit a mixture of hydrogen and oxygen in the perfect ratio to generate a very strong explosion. While the gas emssion is strongest during charge, it is happening all the time. Lead acid batteries explode on a regular basis. That is why battery boxes are always vented. I have been in the area twice when batteries exploded. One was a box with three 12 volt deep-cycle marine batteries exploded in their not-well-enough ventelated battery box on a schooner. All three batteries were ruptured. In anyother case a friend was jump-starting a car. In that case he got battery acid in the face. Happily he was wearing glasses. Lead acid batteries need ventilation - especially during and after charging!

/// Frank ///

[barrington]

Kim, pay attention to what Frank says, he's right. I bought a 12v 31ah U1 battery from West Marine for about the cost of your set up. I lay it on it's side to fit under the seat (something you can't do with wet cell batteries) and use terminal protectors. It measures 8.5" x 5.5" x 7.5" approx. I also bought a small solar panel and have never needed to charge my battery! Best of luck

Chris

[Kim Whitmyre]

Thanks for the heads up, guys: I'll inquire about the venting. :eek: Your setup sounds nice, Chris. What kind of solar panel did you get?

[JimConlin]

Aren't some lead-acid batteries sealed?
If so, why does ventilation matter?

[willmarsh3]

I'll add to Frank's word. It doesn't take much hydrogen and oxygen mixture to do some serious damage. I had a battery blow up on our race committee boat last year. It was ventilated but it was charged with an automotive battery charger that was kept plugged in all the time. Also no one checked the level inside the battery. Evidently it reached full charge, then started bubbling until the electrolyte level in some of the cells went down. The plates became exposed. At some point a spark occurred. The explosion from inside the battery ripped a big ragged hole in the top of the cell. That was maybe 20 cubic inches of hydrogen and oxygen gas mixture.

To fix our problem we got a 3 stage charger along with a new battery.

I should point out though that using a 3 stage charger will not reduce the evolution of gas sufficiently to permit a sealed case like that.

I've read about Gel Cells and AGM and also caps that recombine the oxygen and hydrogen but I still wouldn't bet on these. I had a gel cell get subject to over voltage because the voltage regulator on the alternator failed. When I got to the dock and pulled the battery out it was hot, hissing gas and had spilled acid in the case.

I hope I'm not sounding critical. But this is the stuff I've run into in my experience and I don't wish it on anyone.

[Frank Wentzel]

Some lead acid batteries are called "sealed" but they are not! I worked on cylindrical sealed lead acid batteries. The battery vent supposedly was sealed up to 60 PSI. To check out venting characteristics I potted a 12 volt, 5 amp/hour battery in epoxy (what else?) and lead the gasses through a volume measurement system and then into a gas anaylser. In our literature we maintained that the battery wouldn't vent any hydrogen because we used a balance of plate sizes that would only generate oxygen. This oxygen was supposed to recombine at the negative plate for a net "no gassing" battery. We all believed our propaganda! It had to work that way because that is how we designed the battery! The advertising copy writers were wrong! The battery generated gas continuously. Of course, gas generation was highest on overcharge and high during charging but it was continuous at low levels even when the battery was inactive. The gas mixture never varied - it was always 2 volumes of hydrogen per volume of oxygen.

Any battery that uses a water-based electrolyte will vent an explosive gas mixture on overcharge. Do not seal batteries in a gas-tight container! Even dry-cell vent explosive gasses under some circumstances.

/// Frank ///

[Pokey]

boy thanks Frank
this sounded like a great idea but it's not
Lee

[JimD]

Fortunately, at least hydrogen is lighter than air and will not pool in the bottom of a container or a bilge. It will rise harmlessly out of the boat as long as it has a vented path to do so.

[adampet]

Ya know I've looked and looked at this and I can't find anywhere where it says this is a lead/acid battery. There are lots of types of batteries these days . It's entirely posssible this battery is a NIMH or other.

any one with more info?

Adam

[Nordicthug]

I was curious what battery was supplied with the package, so I emailed 'em and asked. That should sort out the controversy, don't you suppose? As soon as I get an answer, I'll post it here.

Gerry

[Rational Root]

I had a pelican case for my camera.

Took the camera on a raft down the Colorado in big water.

(That was scary - take that from a guy with 300+ skydives)

Tough cases.

AFAIK there is a pressure vent in them.

[paladin]

You can purchase the boxes with and without pressure vents. I supply a similar box as an accessory box for use with some electronics warfare devices.....but I use NiMH batteries, and specify that the boxes must be open during charging, even though there is no venting......batteries heat up during charging and I have both fuses and thermistor protectors in the case to shut everything down during overheating. I also install small computer type fans inside the case to circulate cooling air anytime the charger is turned on. NiMH batteries are more expensive...but safer for many applications. The newer 4/3 A batteries are 4.5 ampere hours per cell, so I can have 12 cells per pack for 12 volts nominal at 4.5 amps, and isolate a number of packs for higher capacity, the charger acts independently with each pack for sensing/charging. System works in any position, and you can put a bullet through one pack and it keeps on working......

[Nordicthug]

I got an answer from them. The guy who wrote the email hasn't a clue, all he said was "12V, 10 amp. supplied by Gruber Electronics".

I replied and asked this time which specific battery, IE: lead/acid, Ni-cad, nimh, and Li-ion. We'll see what they say soon.

It can be difficult some times dealing with someone whose job it is to sit at a keyboard fabricating answers. Why can't they simply admit they don't know, then refer you to someone who might?

Got a straight answer. Lead / acid.

Gerry

[paladin]

If you go to digi-key, you can get 6.5 amp hour "D" cells, NiMH.....buy 24.......and a 10 K thermistor (2 each) and thermal fuse.....initial cost is more, but you can get virtually unlimited recharge capability, 12 amp hours, no explosions, 14.4 volts at full charge, buy the same box and the cost in the long run is less......a 90-260 v, 40-65 hertz charger will cost about 35 bucks, use the appropriate connectors etc....

[Dan McCosh]

Kim, pay attention to what Frank says, he's right. I bought a 12v 31ah U1 battery from West Marine for about the cost of your set up. I lay it on it's side to fit under the seat (something you can't do with wet cell batteries) and use terminal protectors. It measures 8.5" x 5.5" x 7.5" approx. I also bought a small solar panel and have never needed to charge my battery! Best of luck

Chris


I was going to mention the same battery. It's mainly for skidoos and such--have two smallish sizes at West. Sealed and pretty much foolproof., plus much more capacity than the one you noted.