I just put the final touch on the front step I built (see A New Step). While taking photos of it, I also snapped one of the cover to the battery box, which I built a few weeks ago (see Racing to the Summer Solstice).
Dri-Dek® puts the finishing touch on the new front step (Photo: Mark A. Zeiger).
When I first built the step, I grabbed a few squares of Dri-Dek® tile (paid link) left over from our sailboat, Selkie, and put them across the step in place of a doormat. It worked great, although we tended to catch our feet on it going in sometimes. I then remembered that Dri-Dek also offers edges and corners that bevel to the floor surface, so I ordered enough to round out the squares. Once done, it looked almost as if I had built the step with the tile dimensions in mind!
I had intended to anchor the tiles with some screws in the joining loops along the back edge, but I’m going to wait a bit. If we don’t slide around on it, then I’ll leave it unanchored, so it’ll be easy to pick up and sweep beneath every now and then.
The completed battery box (Photo: Mark A. Zeiger).
As for the lid to the battery box, please don’t scrutinize it, it’s far from perfect. But, considering I built it on the fly, it fits together pretty well, and it covers the battery bank well enough that I have to get after the family for putting stuff on top of it, like cooling hot dishes and the like. At any rate, it’s a whole lot safer than leaving it open, like it had been at first. I was afraid the cat would jump up on there and fry herself!
You’re running a 12V or 24V system the cat would be unable to fry herself on those Voltages.
I am a little concerned that the lid fits too well.
Lead Acid batteries should have some ventilation both for cooling and as they can vent Hydrogen and Oxygen under certain circumstances and you don’t want a large explosive mixture to build up.
I know these are a different technology but some ventilation is probably still a good idea.
Ekji, I wouldn’t want to drop a tool across terminals, nor would I grab them with bare hands. A cat jumping onto an exposed bank might get into more trouble than it can handle–that’s what I hope to avoid. Besides which, I want the batteries to stay clean, I don’t need cat hair in there as well as everywhere else on the property!
I’m relieved that you’re concerned my lid is too tight–that means I managed to take photos that don’t show how loose it really is! I cobbled it all together on the fly without much more than a casual sketch, so I guess I should be happy it doesn’t look any worse. There’s plenty of ventilation in that fit, believe me!
Interestingly, the Web pages for NiFe all talk about how no ventilation is needed for these batteries, yet when the real “paperwork” came, it recommended almost the same levels of ventilation needed for lead acid. I’m much more satisfied with the ventilation on the new bank over the old one, which has a snorkel-style exhaust through the wall and a fan that kicks on after a certain voltage level is reached. It never seemed to do the job as well as it should have.
Your skin impedance is about a million times higher than that of metal.
So while dropping a metal tool across a 12V battery would be bad, touching both terminals at the same time with bare hands you wouldn’t even feel a tingle. You would need some very unusual circumstances to have an issue with 12V such as if you cut your finger to the point where it was bleeding and rather than bandage it up you kept working, now the electricity has a path straight to your blood bypassing your high impedance skin, this could get ‘interesting’. I suspect you’d still be OK unless you had a similar cut on your other hand and touched both terminals with the bloody parts of each hand, but I respect you erring on the side of caution.
That’s fine, Ekij. I’ve also read from many, many sources to make sure you don’t connect the terminals with your body. I also had a friend who felt it was perfectly okay for his toddler to stick metal objects into a household outlet–“She’ll get a nice shock, and she won’t do it again!”
I will not be risking myself to test either of these assurances. I prefer to err on the side of caution. I can’t see how the slight inconvenience of avoiding contact with both terminals would outweigh the possible consequences.