Early conventional aluminum electrolytic capacitors were known to lose electrolytes through outgassing, over time. The loss of electrolytes, a.k.a. “dry-out” results in loss of capacitance and increases in ESR. Newer conventional package types such as snap-ins, screw terminal, axial, and radial leaded parts have come a long way in the past couple of decades. They are less likely to dry out than the electrolytic types of yesteryear but there are some loss of electrolytes over time and the concern over dry-out still persists today. Military/Aerospace design engineers are designing-in C.O.T.S. parts where appropriate, but tend to favor CDE’s near-hermetic Flatpacks and true hermetic capacitors, including hermetic wet tantalum capacitors, for their mission critical applications. The graph on this slide compares the weight loss of electrolytes with time for a non-hermetic Flatpack versus a hermetically sealed Flatpack. Although the weight loss for the standard (non-hermetic) Flatpack capacitors is minuscule (orange curve), it can be seen that the hermetically-sealed part did not lose electrolytes over time on test (yellow curve).