Patriot666
Super Freak
My advice is to verify all the batteries inside your collectibles. No matter if cheap cell ones or larger AA or AAA - they can all leak. If you want batteries inside your collectibles use high quality ones: for AA/AAA try Duracell, Energizer or Varta, for cell ones try Renata (also used by Rolex). Make a simple list with the expiring dates of the batteries from your collectibles and replace them in time.
Good advice. I used to swear by Duracell, but I've found multiples leaking recently. None in my collectibles but in remote controls and toys. I will never leave any battery in my collectibles anymore.