" Mr. Freeze bids farewell to Gotham City via a permanent deep freeze! Both Batman and Bruce Wayne must determine Freeze's motives in order to stop him from icing all of downtown Gotham!"--DC Solicitation. 
 
Cold Snap Part 2.
 
Batman discovers Freeze's real motives about stealing those seemingly random items, he was punishing himself for almost forgetting Nora, and now was trying to surround himself with all things that reminded him of her and hopefully dying with her memory, Batman tried to save him but the place exploded, Batman got out and was pretty sure that Freeze had gotten out too.