Implantable medical devices (IMDs) and components, including flat electrolytic
capacitors and methods of making and using same, particularly an improved electrolytic
capacitor fabricated of an electrode stack assembly comprising a plurality of capacitor
layers stacked in registration upon one another. Each capacitor layer comprises
a valve metal cathode layer having a cathode tab, a valve metal anode layer having
an anode tab, and a separator layer located between the cathode layers. The anode
layer is assembled from a plurality of valve metal anode sheets that are etched
and anodized, stacked side-by-side, and electrically and mechanically joined together
by laser weld beads. A valve metal anode tab having a thickness equal to one or
more anode sheet is inserted into a tab notch in one or more stacked anode sheet
and joined to the anode sheet stack by laser welding the tab and sheet edges together.
