House battery frame and venting, Post 5
Need to add vent fans to the lid. Even though hydrogen is lighter than air and should naturally flow out if the vent outlet is higher than the inlet I want to give it some assistance. The amount of hydrogen gas produced by a charging battery at any one time is fairly small so I won't have to move a great deal of air. I'll be using small 12 volt "muffin" fans. This is a induction type fan so it has no brushes that might produce electrical sparks like a regular motor.
I'll make the fan enclosure from some scrap pieces of plexiglass. Create a mock up from cardboard first.
Then use some smoking matches to see if it will really move air through a hose. It does.
Start work on the plexiglass version. As an added safety feature stack wire mesh to create a flame arrestor between the fans and the inside of the vent lid.
Countersink the edges of the hole then sandwich the wire mesh between two plexiglass pieces. The countersinking allows the two pieces to be in contact over their length with the wire between. This will be the base of the fan enclosure.
Start cutting and drilling plexiglass pieces as I come up with a design.
While most of the enclosure is glued together I want to be able to replace the fans if needed.
Drill and countersink holes for nuts.
Starting to take shape.
Added small rectangular pieces to the inside to keep the fans in place.
Use a bead of silicone around the edges of the fans to increase air flow. Then do the same to the edges where the enclosure screws together.
Completed.
Hook it up to a power supply to check that the fans run and I didn't gum them up.
Attach a length of hose and see if it will move some air.
It does. It will almost blow out a lit match.
Figure out where to position it on the lid.
Add connectors to clean up the wires.
Use a bead of silicone where the fan will bolt to the vent lid.
Here's the view from inside the lid looking into the fan enclosure before I cleaned out the excess silicone. Am I the only one who thinks this looks like a jellyfish?
This is the original vent lid I made for the first battery box. I'm about to use a hacksaw to remove the bungee cord hold downs from the lid ends.
Success.
Here they are attached to the new lid.
continued -
On a different note this is what I've been working on today. The kitchen cabinet is starting to take shape.