Detect laptop batteries with a scanner????

Archived from groups: comp.sys.laptops (More info?)

Hi All

I recieved a post from a bloke who reckons that you can detect Nicads with a
frequency scanner and insists that crims use such a scanner to detect
laptops in cars in parking stations for the purposes of theft. He insists
that the police have told him that this can be done.

Can this be true? Do batteries emit a frequency even when not in use? Could
you detect it through the metal or glass shell of a car?

I find it impossible to believe, but am caught by the "can it be true?" side
of things.

Regards

Peter