Truck tool box as battery box...

Re: Truck tool box as battery box...

I always wear safety glasses when working with batteries. Especially when topping off the water.

Is this box going to be mounted indoors? You mentioned residential space in the post. If so you need to make sure your vents go outside. Also make sure you have an airtight seal on the lid.

I remember seeing online where someone built a battery box of wood and used it inside a cabin as a window seat. He simply vented to the outside wall and sealed the inside of the box.

I would NOT ground the box. A loose + battery cable hitting the side of the box will spark if the box is grounded. Better to have it isolated if you ask me.

Also, wear gloves and rubber soled shoes when working on the batteries. I received a bit of a jolt when I went out in the middle of the night to check connections barefoot. Got a pretty good tingle just touching the + cable. Lesson learned.

Re: Truck tool box as battery box...

I think rubbermaid has a plastic patio bench seat with "storage" under it, and some have used those as battery boxes with success.

Re: Truck tool box as battery box...

divonbriesen wrote: »

Thanks for the info guys-

Now i'm bumming... i thought I had an elegant solution. In fact I almost picked up the box yesterday.

So I'm guessing the midnight solar box I have is not ideal either - it's steel, and painted, so that might address some of this.

The project is to build a suitable residence for 2 inside the shipping container- so i'm hoping to use the box as furniture as well- but we need to make it easy to teach at the same time (i.e. show people how it's wired). A plastic box will look pretty ghetto compared to a diamond-plate metal box.

Would your answers be any different if I asked about the same box, but painted black, instead of unpainted chrome aluminum?

Does it matter that these batteries are sealed?
Would it matter if I coated the bottom, or used that shower rubber mat underlayment to create a basin along the bottom and up the sides?

Here's a shot of the setup (remember, it's for teaching, so more obvious and out there than normal) and you can see the corner of one of the boxes in it. This is in the main living area:

http://www.flickr.com/photos/divb/5010787558/

here's a shot of the overall project, before i added 2 more solar panels: http://www.flickr.com/photos/divb/4897041398/in/set-72157624610877817/

Thanks everyone!

d.i.

So face the ABS truck box with some diamond plate,
Make sure the container is air tight and well vented to the outside. Hydrogen gas is nasty stuff.

Re: Truck tool box as battery box...

I don't see why you couldn't just line the inside of the diamond plate box with some 1/4" or 3/8" plywood.

Re: Truck tool box as battery box...

I would just build a box out of wood. You can make it look nice, it won't cost much, it can do double-duty as a bench and it's non-conductive.


It seems to me though that you've got conflicting goals for the project. One the one hand you are making a teaching tool, on the other hand your web site says you are striving for "good design" and an easily deployed housing solution.

I have thought about this some in the past, and here are some of my thoughts on the subject. Might give you some ideas.

What I came up with, was to divide the box at one end (probably the end with the doors). Say the box is 20' long - the living area is 17' and the "utility" area is 3'. You put all the equipment - electrical panel, water heater, air conditioning etc. in that one end, and have it accessible from the outside (probably facing the breaker box inward for access from the living area).

When closed up, it's just a container on a trailer with nothing hanging out anywhere, and when deployed it's easy to access the utility gear. Assuming for the moment that the unit is used for temporary housing for disaster relief. It won't be used as a "green" housing unit and many of them need to be deployed in a hurry. You place the units in rows, with the "utility" ends facing a common "alley". You can then quickly and easily connect water, power and sewer to them by running it along that alley.

Sewage will be a problem, so they could alternatively be setup with a holding tank for waste which could be emptied by a pumper truck running down the alley. The waste tank would also be in the utility closet end of the unit. With that sort of setup, they could be set directly onto leveled ground. If they were elevated like yours is, then you could put a waste storage tank underneath instead for increased capacity.

For temporary housing, they could just as easily have fresh water tanks that could also be filled by trucks running down the alley.

By standardizing on that sort of design, it could be used for units of any size - 20', 30' or 40' and mass conversion would be straightforward.


For a battery powered unit, putting the batteries inside the living area is not a great idea if they are vented batteries. It can be done, if there is adequate ventilation, but that brings problems of insulating the living area. Better to divide the container at one end, and put the batteries and other utility equipment in that end, and you can vent that compartment all you need without compromising the insulation of the living area.

The overhanging roof you have is fine for a permanent unit, but it's not practical for a portable unit that has to move down the road on a trailer.

A portable, self-contained unit has basically the same issues as an RV; limited roof space for solar and limited storage for fresh water and waste.

Waste water can be used for irrigation, but not if it contains sewage (or chemicals). Composting toilets are maintenance intensive, and often don't work well without a heat source, which consumes electricity. There is an incinerating toilet which produces sterile ash, but the thing consumes a large amount of power - something like 1kwh per use and it uses specially made paper bowl liners.

For disaster relief, it might be better to not include toilets at all. In that case, you could either use porta-potti units, or design a container conversion with say 8 or 10 "restrooms" with toilets and showers in them and deploy one in every "block" of living units.

Food is another problem. The PV system and batteries could probably handle a small refrigerator, but I doubt that it would provide enough power to also cook using electricity. Now what? Again, for disaster relief, that can be handled with centralized food preparation, but for an off-grid "green" unit, you have to address the issue in the unit itself. Many off-gridders end up using propane for cooking and/or running propane refrigerators.


Looking at your list of proposed uses, I come to this basic question; Is there a grid or not? If there is, then there is no need for solar. If there is no grid, and the unit is permanently installed, then you have a cabin. If there is no grid and the unit is portable, then you've got an RV.

All of these scenarios have their own issues which have been addressed fairly extensively, and many of the problems already solved.

One great resource, with loads of great ideas are "bus conversion" web sites. Those people have tried literally everything.

Container conversion is already a large global business so there are a lot of great ideas out there. Here's a site with some decent links:

http://www.conexconnection.com/

Re: Truck tool box as battery box...

We should be certain regarding the battery type.

That a battery is "sealed" tells us little. My concern is that they may be "maintenance free." Such type can spill and vent freely. Often sold as Marine/RV Deep Cycle. Just an FLA with no access to the cells.

I don't like Gel batteries because the electrolyte can become "pocketed" and their charge criteria is significantly different than FLAs. AGMs and FLAs are similar on such characteristics.

AGMs are unspillable. They can be mounted in any orientation other then upside down. Their cases can be cracked and no acid will flow. AGMS are also calle VRLA (valve regulated lead acid.) Meaning that, if they are over voltaged, they will vent hydrogen. (2 psi is a common limit.) The key is to insure that the charge controller knows this and can adhere to this requirement.

K

Re: Truck tool box as battery box...

dwh wrote: »

When I was an apprentice, the journeyman I worked with bought a new set of "Kleins" (lineman's pliers). The first thing he did was break out his pocket knife and cut off the insulation on the handles. Naturally, I had to ask why. Here is what he said:

"Because you can't trust this stuff. After a day or a week, the insulation will get nicked and you probably can't even see the nick, but you can get shocked from it. So I take this stuff off and when I NEED insulation, I wrap the handles with tape. BUT, I only trust that for immediate use. If I have to do it again tomorrow, I start over with new tape so that for at least a while I KNOW that the insulation can be trusted."

In that case, the insulation was being trusted to prevent shock from a 600V powerline.

For batteries, you are not going to get insulation pucture, you are trying to prevent 48V from arc welding your wrench / screwdriver across the battery terminals. A nick or 3 won't matter, unless its at the end which hits the other terminal.

Re: Truck tool box as battery box...

niel wrote: »

i'm a bit confused as to why a lineman would ever trust a thin layer of electrical tape instead of a thicker molded insulation when dealing with high voltage. if he's in doubt then why not wrap the el tape over the standard insulation that came on the pliers as that would be double insurance and less work?;)

Dunno, I didn't ask. For myself, that's what I do - tape over the factory insulation.

It may have been that he habitually removed the tape when he was done with it - by drawing a knife blade down the handle to just cut it off - while I would unwrap the old tape and wrap on some new.

for us, as mike said, it is so we don't short the batteries accidentally and not due to a shock hazard.

Of course, I do understand that. I was just making a comment in regards to taping tools for electrical protection to illustrate that it's not a good idea to *trust* the insulation unless you *know* what its current status is.

I.e., don't tape it up today and then tomorrow assume it will still protect you. Default to distrust and start over each time.

Re: Truck tool box as battery box...

Can't trust gloves either for the same reason - might be nicked.

When I was a working electrician I had a set of "sleeves" (rubber gloves that go up to the shoulder and have a strap across the back to keep them on) that I kept in a plastic toolbox all by themselves.

I almost never used them though. Usually only when disconnecting/reconnecting an underground utility feed. Overhead drop I could do from a fiberglass ladder so I didn't need the sleeves.

I've watched linemen crimping overhead drops to new service entrance wires coming out of a weather head any number of times. Some wore gloves, some didn't. The gloves I saw them wear were the standard issue canvas dipped in rubber - but they were always pretty beat up so I doubt that the linemen trusted them for insulation...probably used them so they didn't get busted for OSHA non-compliance.

Re: Truck tool box as battery box...

Linemen are generally pretty well trained, and few of them get killed, even though they often work in very hazardous conditions. Talking to a roving repair lineman who makes a great living traveling around N. America doing service repairs after storms, everything they do all over the country is by rote. Some of the nuance is different, but the SOP is the same all over. Ground the conductors, open the fuses etc. That way they can go into nearly any area and work on the line(s) with strangers and not get into trouble.

So whether or not one wears a glove, or tapes ones tools is largely a matter of convention I would guess.

Tony