jtsmith
Registered
I have tried J-valve's idea of just sealing a lead acid battery and it doesn't work.
First off, a regular SLA battery has vent caps and the only way to seal them is to cover them with a potting compound of some kind. I tried this and basically had a square block of rubber with 2 wires coming out.
It worked fine for about 3 dives and then it got to where it wouldn't charge near as well or last near as long. I soon noticed a bulge in the side and found a large air bubble growing. It eventually caused the potting compound to crack and then water got in the battery.....it was toast at that point.
From further research I found that SLA batteries do discharge a small amount of gas even if you charge them gently and do not overcharge.
Another failed canister was a completely sealed one that I made just had charging terminals on the outside. This was my first canister and it eventually blew the switch boot off to outgas. I later added a vent plug for charging and found that this design works really well. The only limitation is that you can't use high power bulbs or heat became a problem.
~JT
http://ecra.emeraldcoastboating.net
First off, a regular SLA battery has vent caps and the only way to seal them is to cover them with a potting compound of some kind. I tried this and basically had a square block of rubber with 2 wires coming out.
It worked fine for about 3 dives and then it got to where it wouldn't charge near as well or last near as long. I soon noticed a bulge in the side and found a large air bubble growing. It eventually caused the potting compound to crack and then water got in the battery.....it was toast at that point.
From further research I found that SLA batteries do discharge a small amount of gas even if you charge them gently and do not overcharge.
Another failed canister was a completely sealed one that I made just had charging terminals on the outside. This was my first canister and it eventually blew the switch boot off to outgas. I later added a vent plug for charging and found that this design works really well. The only limitation is that you can't use high power bulbs or heat became a problem.
~JT
http://ecra.emeraldcoastboating.net
