Heres a couple of questions for someone who knows about batteries.

I have two hand held radios which I rarely use. An Alinco dual bander with
Nmhi batteries, and a commercial UHF with Nicad batteries. Both sets of
batteries are in good order and hold a charge well. I can leave them for
months and when I pick the radios up, they still have a good charge in
them.

Today I lifted both radios, the first time in a month or two, and both had
totally flat batteries. I know both were fully charged when I last
switched them off. What happened? The weather has got warmer in the last
month, and the humidity levels are up. But nothing else has changed. What
flattened them both?

Also...

Last time I took a hand held radio abroad, I took 2 sets of batteries.
Both were fully charged when they were packed. Both were flat when I
reached my destination. Same with my mobile phone and camera batteries as
well. All were nearly flat and had not been switched on during the
journey. What is it that makes batteries go flat when travelling in a
pressurised aircraft?


All secondary batteries have a self discharge rate, some types are higher
than others, a couple of months is more than sufficient to self discharge a
battery pack. Another factor to take into consideration is that most modern
handhelds do not have a 'hard' on/off switch. There is always a small
standby current drawn. It is best to actually remove the pack from the
radio.

As far as batteries on aircraft; I have never had any problems, and I can't
think of a mechanism that would discharge them.

regards
Jeff