jtsmith
Registered
I saw several questions about making a completely sealed light canister and using a diode for charging and thought I would contribute my experience with this.
First off, there is no true sealed canister...you must have some kind of vent hole. All sealed Lead Acid batteries discharge hydrogen when charged, some less than others, but even gel cells produce some hydrogen, if you don't vent it, you will have a nice pressurized hydrogen bomb strapped right next to your extremely high pressured air tank...NOT GOOD!
So, since you need to make a vent hole....I have used a brass plug threaded right into the PVC endcap and just have your charging wires stuffed right behind it. You use needle nose pliers and grab them out to charge. The diode is not needed for this type of design.
I also use my air gun/compressor and spray some compressed air through there using a straw to flush out as much Hydrogen as possible. I usually do this right before I leave to dive since I peak charge it before dives. Don't forget to use some teflon tape on your brass/stainless plug.
If you do want to use the diode method I recommend using the 6 amp diodes because they produce less heat when charging. They do eat about 1 volt of your charging voltage so you will also need a variable voltage charger in order to get your batteries fully charged. Also, charge very slow...a sealed canister does not like heat!
Hope this helps!
First off, there is no true sealed canister...you must have some kind of vent hole. All sealed Lead Acid batteries discharge hydrogen when charged, some less than others, but even gel cells produce some hydrogen, if you don't vent it, you will have a nice pressurized hydrogen bomb strapped right next to your extremely high pressured air tank...NOT GOOD!
So, since you need to make a vent hole....I have used a brass plug threaded right into the PVC endcap and just have your charging wires stuffed right behind it. You use needle nose pliers and grab them out to charge. The diode is not needed for this type of design.
I also use my air gun/compressor and spray some compressed air through there using a straw to flush out as much Hydrogen as possible. I usually do this right before I leave to dive since I peak charge it before dives. Don't forget to use some teflon tape on your brass/stainless plug.
If you do want to use the diode method I recommend using the 6 amp diodes because they produce less heat when charging. They do eat about 1 volt of your charging voltage so you will also need a variable voltage charger in order to get your batteries fully charged. Also, charge very slow...a sealed canister does not like heat!
Hope this helps!
