Kevin W.
Google
The only way I know how to access it is a long walk, but I think a public bus may drop off outside (saw a few green ones).
I personally think its a bit expensive to get in, but once inside its immaculate so you see where the money goes.
I liked the comic book style drawings, the tunnel and getting a whole feel for the place.
The only thing I'd say is if you intend to walk there, and see both the old and new battery allow plenty of time, because the new battery shuts at 4pm old battery 5pm so we hadn't allowed enough time to do both.
Definitely nip into the cafe at the old battery as the coffee and cakes were amazing.