CELL STACK AND CELL STACK ASSEMBLY

An electrochemical cell stack () comprising a plurality of stacked cell units (), each defining an external perimeter, a housing () surrounding the stack () to define a volume around the external perimeters, and at least one electrically insulating beam (), the beam () extending generally in a stacking direction of the stacked cell units (), to extend across a multiple of the cell units (), and located between the external perimeters thereof and the housing (), wherein an electrical connection member () of the cell stack's current delivery system extends inside the electrically insulating beam ().