I was referring to the zinc-air cells used in hearing aids. They are
also very similar to mercury cells in characteristics but comparitively
short lived. Mercury cells in applications like exposure meters lasted
for years. Once the air seal is removed from a zinc-air cell it has a
life of perhaps several weeks. I have been keeping track of the ones in
my Nikon F. I also have hearing aids that use zinc-air cells. They are
much smaller than the ones in the camera. I found that even without use
they do not last more than a couple of weeks once the seal is removed.
I suspect its possible that a mercury cell recycling program could
be made workable by charging a returnable fee as some states do with
bottles. Administrative costs might be too much for this to be practical.
On 12/9/2016 1:12 PM, Tim Daneliuk wrote:
On 12/09/2016 03:03 PM, `Richard Knoppow wrote:
The life is fairly shortThat's surprising. My experience using them with the CRIS adapters
is that they last a very long time, much like an ordinary battery.
Then again, I turn the meter off when not in use.
The problem with replacing mercury cells is that they had very constant voltage
until almost dead.
That's why silver oxide is such a good choice. It mimics mercury battery
behavior very nicely.
