Print PDF
Favorite
Email
Step 3How it works
of course you are wondering - how does it help to put the waterproofer only around the dimple? what about the rest of the battery?
The entire can of the battery is made from stainless steel - totally rust-proof. so why does it rust? its because right around the dimple area is where the positive and negative of the battery meet at their closest point - and when water gets into this area, it allows electrolytic corrosion to occur - the electricity from the battery flows through the water, and this causes corrosion of our otherwise impervious stainless steel (as well as rapidly discharging the battery!)
So - all we need to do to make the battery impervious is to apply our waterproof coating around the dimple area, covering the area where the positive and negative are near each other.
Check out the photos below, where i've peeled away the plastic wrapper at the top of a battery to show this in detail. the bottom (negative) end of the battery actually extends under the label and up the sides of the battery all the way to the top - where it is separated from the positive (dimple) end only by a thin rubber seal. its very easy for water to get in the groove next to the seal and create a conductive path from positive to negative. the battery also is made with a fiber washer around the dimple - this protects this area from getting damaged (without it it would be too easy to short out the battery by dropping a screw next to the dimple) - but the standard fiber washer that is used soaks up water quite well, providing lots of nice water to corrode the battery.
in the 2nd photo i show the safety-pressure valve. if you accidentally over-charge your battery this valve will open to prevent the battery from exploding. if you are using a fairly thin or flexible waterproofing material the valve should not have a problem still working, but you probably don't want to use epoxy or any really thick or strong material as it will block the pressure valve from working in the rare case that it needs to.
The entire can of the battery is made from stainless steel - totally rust-proof. so why does it rust? its because right around the dimple area is where the positive and negative of the battery meet at their closest point - and when water gets into this area, it allows electrolytic corrosion to occur - the electricity from the battery flows through the water, and this causes corrosion of our otherwise impervious stainless steel (as well as rapidly discharging the battery!)
So - all we need to do to make the battery impervious is to apply our waterproof coating around the dimple area, covering the area where the positive and negative are near each other.
Check out the photos below, where i've peeled away the plastic wrapper at the top of a battery to show this in detail. the bottom (negative) end of the battery actually extends under the label and up the sides of the battery all the way to the top - where it is separated from the positive (dimple) end only by a thin rubber seal. its very easy for water to get in the groove next to the seal and create a conductive path from positive to negative. the battery also is made with a fiber washer around the dimple - this protects this area from getting damaged (without it it would be too easy to short out the battery by dropping a screw next to the dimple) - but the standard fiber washer that is used soaks up water quite well, providing lots of nice water to corrode the battery.
in the 2nd photo i show the safety-pressure valve. if you accidentally over-charge your battery this valve will open to prevent the battery from exploding. if you are using a fairly thin or flexible waterproofing material the valve should not have a problem still working, but you probably don't want to use epoxy or any really thick or strong material as it will block the pressure valve from working in the rare case that it needs to.
| « Previous Step | Download PDFView All Steps | Next Step » |
 |
Add Comment
|
