Neodymium power cell

From Memory Alpha, the free Star Trek reference.

A neodymium power cell was a type of power cell used in Cardassian phase-coil inverters.

In 2373, Doctor Elias Giger requested a neodymium power cell (among other things) from Jake Sisko and Cadet Nog in exchange for a mint-condition 1951 Willie Mays rookie baseball card. Jake and Nog were able to locate the equipment with Chief O'Brien's help. (DS9: "In the Cards")