A stacking apparatus and a method for assembly of electrochemical cells. The stacking apparatus includes at least one stacking head having an adjustable holding member adapted to hold an electrochemical laminate of a pre-determined length and means for adjusting the shape of the electrochemical laminate of the pre-determined length during stacking of a plurality of electrochemical laminates. The electrochemical laminates are assembled in a way that prevents air entrapment between the electrochemical laminates.