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AMP20 Cell Pressure Uniformity
Another advantage of a compliant pad between the cells is that pressure is kept relatively constant across the
whole surface of the cell. Figure 10 shows simulated pressures at various points across the cell with and without
the compliant pad in place.
Figure 10 – Pressure on AMP20 cell face without compliant pad (left) and with compliant pad (right)
Another factor that can affect the uniformity of the cell pressures is the rigidity of the end plate exerting pressure
on the very end of the cell stack. The more flexible this is, the more variation in pressures one will see on the end
cell’s face. The best way to determine this variation is by FEA simulation of the design. Figure 11 is a 3D graph
showing the variation of pressures across the face of a cell using a particular end-cap design. The differences are
visually more striking than they really are. In this particular design, the pressure variation across the pack is only
+5/-2% off the average. The figure shows the results of a non-ideal but acceptable end-cap design.
Figure 11 – Pressure map across the surfaces of each cell in a representative stack of cells
