In article ,
"Jack VK2CJC" wrote:

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?

I hope someone can advise. I've been thinking about the aircraft one for
ages )

73

there is probably a few thing gong on

firstly when you saythe batteries are 'fully' charged are you shooting
from the hip or actually measure both volts AND amps?

if not that your premise, 'batteries are fully charged' isn't prob as
good as you thought

as you stated you've had these batteries over time as they age they
have diminished capacity , they will not hold the amp/hr rate for as
long UNDER full LOAD while a quick voltage check or radio on test
might make it appear

the things the other folks said are also true higher temp will reduce
the battery life for example , that radios also have a small draw
current even when off etc

it's highly doubtful any 'xray' or other screaning machine at airports
had any significant effect millions go thru if everyone had problems
we'd hear about it by now

if you want to learn about the machines and are afraid to ask the clerks
just google it btw i've never seen a machine w/o a name tag but u
do have to know where to look perhaps some were removed


all these things added up are significant (except luggage
screaning)

what most likely happening is that the vibration of the plain caused
the power switch to turn on drain the battery and switch off alot
of strange things happen in packing .... removing the battery and
taping over the contacts should help

otherwise i'd suspect your batteries might just be old and not up to
full snuff

you'd have to make a controlled scienfitic test to be sure whats going
on

best of luck and holidayz