True. But if they stay in contact with plastic too long, they will eventually burn through that.
And the stench...oh man. Phew!
And do watch out not to get any of that stuff on you...it BURNS.  

 

My original G2 laser prime still has its original working batteries inside it, no corrosion and he was bought in spain and lived there for a good few years in all sorts of storage conditions and now resides in the UK with me.

 

Been there, done that.  

 

I don't trust any A, AA or such style batteries they will all eventualy leak. Fortunately none of them are on the circut boards they power so they can't damage them.

I did however leave the 9v battery in my childhood Shockwave for 20 years or so and was supprised that there was no leakage after getting him out of my parents non-climate controlled storage shed, and that he still worked. Needless to say I imedately removed it and threw it away.

 

hmm, all of my electronic figures, I've usually kept the batteries in. The only
time I had corrosion problems was with toys from when I was a little kid.

I dislike toys with batteries though. There's nothing wrong with lights and/or
sounds, but electronic toys, I can't display near my window in case it may rain.