Hi Phil,
I think the initial dendrites DO just spark and
open up but eventually the spacer is damaged
and the short is enough to bring the cell voltage down.
Yes, Zinc dendrites will form also if the battery is
overcharged but we should not be able to do that on
ARISSat-1 so only the silver ones should be an issue.
73,
Tony AA2TX
---
On 8/14/2011 6:56 PM, Phil Karn wrote:
On 8/14/11 3:18 PM, Anthony Monteiro wrote:
I think the explanation is that the battery experienced a
significant event on Aug 11 where it lost the electrolyte
in one or more cells. If this is true, the bad news is
that it will no longer hold a charge and will not operate
in eclipse any more.
I agree with your analysis in that one or more cells seems to have gone
open-circuit, or at least greatly reduced in capacity. If you know these
batteries and their specific failure mechanisms, then I'd say your lost
electrolyte theory is a pretty good one.
I never have understood why the dendrites would not be melted by high
current as soon as they crossed the gap between the two plates. I assume
they grow on the zinc plates as the battery is charged?
-Phil
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