In article , Joe User
wrote:

David wrote:

Got any AAAA's?

break open a 9v battery. a true battery, i.e., made up of multiuple
cells. The cells happen to be AAAA size.

-j

Googling "aaaa cell" found http://www.batterystore.com/Eveready/E96.htm.
That is most certainly not what's inside the last 9V battery I tore open
(granted, that was years ago, but I can't imagine they've changed much).
The 9V was a stack of (6, I guess) flat rectangular shaped cells.