Battery Access Version 2.0.0

I wrote this a couple of weeks ago but then never pushed publish.  It is crazy how much the weather has changed since I wrote it....  Back at that time I was saying "Yeah, remember that snow storm in the forecast this past weekend?  Six inches of fresh snow? Never mind about that, it was almost seventy today." Tonight I am sitting in a bar with an outdoor patio.  It is purely crazy to be living somewhere you can be drinking beer in a t-shirt looking at a snowbank from the bar parking lot plowing that must be twelve feet tall.  Purely crazy.

I have come to the conclusion I have made another mistake.  This one though, this one is going to be a tricky one.  You see, The Wife was the one who said I should build it a different way.  And she’s the very devil when it comes to matters of me being wrong.  In my defense though, I have some sound scientific principles behind the decision I made.  If I was, say twenty seven, I wouldn’t even recognize the problem I have.  Sadly, I am not.

Here’s the deal.  To maintain my cabin batteries in top condition I need to check their fluid level in each cell of the battery.  Additionally, in my case since I had that wiring problem, I really should be checking the specific gravity of the fluid each time with a battery testing hydrometer.  This should happen four times a year.  Each battery weighs 62 pounds.

The battery tucked in under the bed.

What my plan had been was to place the batteries on some polypropylene squares and slide them out each time I needed to.  I figured some 3/8” plastic with some rounded corners would not bend with the weight and slide around pretty easy on the steel of the van floor.  I hadn’t quite figured out how to keep these sixty two pound bricks from sliding around all the rest of the time.  --Like when I am driving down the road and take a corner a little too fast.  I was hoping to work that all out once it had become a problem.  But when I was planning these plans I also hadn’t actually seen a van up close yet.  Once I did, I immediately saw why these plastic slides wouldn't really work.  The van floor isn’t the smooth waffle around the outside parameter like it is in the middle.  It has seams with rubber calk coatings.  No way my plastic slides were going to work in this environment. They would stick to the calk.

I ended up just putting the batteries right on the floor.  They are pretty solid there.  Even though they are not attached down at all, they still don’t slide around.  They are still movable if I need to drag them out like I did a couple of months back for the re-wiring job.

Snow storm that week, ninety this week.

Here’s where The Wife got involved.  She suggested I build battery boxes with access down through the bed.  She suggest I make an access panel I could get at with the mattress out.  The problem with that idea from a safety perspective is when you charge lead acid batteries and particularly when you do what is called equalizing them.  The equalizing process charges them at a high voltage.  The purpose is to remove a film which builds up on the lead plates. The batteries actually boil during this process.  In this case, the steam that is coming out of the pot as it were is pure hydrogen gas.

Remember high school chemistry and the big chart on the wall?  Hydrogen occupies the upper left square.  The significance is this gas has little tiny molecules and it can seep into the smallest of cracks.  Propane gas is both significant larger in molecule size and it is heavier than air.  Any propane I leak in the back of the van will escape out the floor.  Hydrogen on the other hand is lighter than air so it will try to work its way up into the cabin.  Let me switch you from Chemistry to History.  Remember the Hindenburg?

So it was for these scientific reasons along with my opinion of the labor of pulling the mattress out every three months just so I could test the batteries seemed like too much work. I ended up just pushing the batteries back in place and told myself I would pull them out as needed.  The next eight months passed real quick as I shuddered each time I thought about doing the fluid level check.  The batteries were not critically low when I finally did get around to it but they certainly were not great either.

I have come to the realization I am going to have to build the hatch through the bed and confront the gas leakage with some weatherstripping.

At the same time I have come up with an idea for reducing the under mattress condensation problem. I covered this a few posts back with a long list of my possible options.  What I settled on was building something myself.  But since that time my design has changed.  I was thinking of using some strips of 3/4” plywood as spacers, then some 1/4” plywood on top with holes drilled in it.  Then, the mattress on top.  I was never really happy with this idea.  I felt like the mattress would only really dry where the holes were.  I just wasn’t so sure about the area an inch away from the hole.  I was concerned I would still have mold growth.

My new design puts the thin plywood on the bottom.  I would still use the same spacers but stapled to the spacers I would stretch some #4 (1/4”) hardware cloth.  This design would allow airflow almost everywhere.  It will be strong enough to not sag and let the foam block the channels.  I think this will work perfect.  Likely the building of this setup will be one of the next blog posts.