Battery Boxes - Buy vs. Build

[cwarren]

I plan to install two new batteries in our boat and I'm trying to determine whether I need to drop the coin on plastic battery boxes or whether I can make my own. This is what I know of the coast guard regulation:

Batteries - Must be secured so they cannot be moved more than 1" in any direction; terminals must be protected so that metallic objects cannot contact ungrounded terminals (positive battery terminal); and be vented to permit the discharge of hydrogen gas. Batteries cannot be installed directly above or below a fuel tank, fuel filter or fuel line fitting.

I don't want to cut any corners in terms of safety. At the same time, I don't want to spend money on something that isn't necessary. Are there safety concerns associated with making your own battery boxes from plywood?

[cwarren]

Maybe I answered my own question. Based on the following it sounds like it might be a pain building a box that would meet regulation:

http://frwebgate4.access.gpo.gov/cgi-bin/waisgate.cgi?WAISdocID=61747528650+4+0+0&WAISaction=retrieve

I think it really depends on the number of batteries, size, location, and orientation. A plastic box may fit on some boats just fine but others require a custom made one. Check out the Blue Sea Systems website. They make some good boxes.

Raul

[Pegasis]

My understanding is the batteries do not need to be in a box. The battery needs to be secured as you described (whcih can be done using a couple of starboard blocks and a nylon strap) and the battery terminals need to be protected which can be done with those rubberized terminal covers that attach to the cables and cover the terminals.

[heymagic]

Chad, the normal plastic grp27 boxes are pretty affordable, maybe $10 or so. Plywood has been used for many years, venting is just a small hole or two at the top edge. Use West System type epoxy on the wood to preserve it. Roy is correct in that you don't need boxes as such, wood or plastic blocks around the base and a strap to hold it, along with positive terminal cover is legal. Where are you keeping the boat?? Gene

[cwarren]

Very good information. I will be putting in two 8D's (getting them for free so why not). I checked out the boxes from Blue Water Systems, they are very nice. I think I could build something for much less though. The boxes from Blue Water Systems are $70/each including shipping. I have almost all of the supplies in scrap to build them.

We are keeping the boat at Elliott Bay Marina, K-Dock. We are heading to Longbranch Memorial Day Weekend to meet my parents if anyone will be in the area.

[Go Aweigh2452]

pretty sure the same regulations are here as in NY. When there, the inspector required the unused terminals on my grp 24 to be covered (battery had both the top and side terminals). I covered the side terminals with plastic dip coat since I was not going to use them. That was sufficient. I would assume you'd have to do the same especially if you had no box so items would not accidently drop on the open terminals...


thoughts anyone???

When I do Vessel safety Checks I look for the battery to be secured. It can move a bit but shouldn't be able to bounce around. I also look for the terminals to be insulated, protected, etc. If the battery is in a secured, covered box, these requirements are usually met. If the top of the battery is open, I look for covers over the terminals and the connectors.

Just use common sense and you'll be fine.

Raul

The unused terminals come with plastic plugs that screw into the terminals. I think putting those in would suffice. Adding plastic coating would keep them in place too.

Securing them properly and keeping them isolated would be the most important problem. Building a box only adds to the equation. Now you have be able to properly vent the boz as well as protect the batteries.

I'd say... leave the side covers on the unused terminals, go with plastic boxes from Schucks, secure them with blocks like Gene and Roy suggest and you're good to go.

[heymagic]

The 8D boxes are kinda pricey, but you could shop around for some Rubbermaid type containers tha proper size. The batts could still be strapped in and the 'plastic' boxes would keep everything protected. 2 8ds is a boatload of batteries.

[cwarren]

The rubbermaids are a good idea. Yeah, 8D's might be a bit overkill and the weight is probably not a great thing. I think we will be adding about 170lbs or so. We do plan to put an inverter in so hopefully the 8D's prove useful when we are on the hook for a couple of days and it's hard to pass up free batteries.

[sunnydude2]

Check secondwave.com in freemont. They have used plastic battery boxes and you can haggle on the price. I picked up two 6vx2 boxes for $80 that are in excellent condition.

[heymagic]

Chad, even a wussy 8d should top 100 lbs, a good one will go nearly 150 lbs ....

[cwarren]

Yep, I think the two we are getting are 150lbs each. I'm estimating added weight based on removing the two batteries we currently have.

[chuck4788]

Allied Battery has plastic boxes that are about half the price of the Blue Sea models. They also take a little less room for the same size battery compared to the Blue Sea box, but they don't have the bolt down lugs on the outside. I used wood cleats to keep the boxes from sliding and a 1 inch wide cargo strap over the top to keep the lids on and prevent tipping. So far so good, no problems with setup for last seven years.
Another idea: Bayliner bolts their 8D boxes to the center of a sheet of plywood about 4 inches larger than the battery box. The plywood in then secured to the boat with a sheet metal screw on at least three sides. The battery box can be moved by undoing the screws, makes battery change a little easier. With 8Ds at 150# each, sometimes moving the box a little can really help

[chuck4788]

I have three Bayliner 8D boxes for sale. They are the original dark grey plastic mounted on plywood. include lids. Located in Tacoma, send me an email.