Implantable medical device having a capacitor assembly with liner

An implantable medical device comprising a housing 90, a capacitor assembly 64, an electronics module 92 and an energy source 94, such as a battery. The capacitor assembly is disposed within the housing. The electronics module is electrically connected to the capacitor assembly and similarly disposed within the housing. The capacitor assembly comprising a case 100, an electrode stack 108 and an insulative liner 170 between the case and the electrode stack. The capacitor assembly electrode stack comprising a plurality of electrode subassemblies each having a plurality of anode plates 150 and a plurality of cathode plates 152 with a separation layer 154 between anode and cathode plates. The liner also maintains alignment and immobilizes the electrode stack within the capacitor assembly. Finally, the energy source is electrically connected to the electronics module. With this configuration, an overall shape and size of the implantable medical device is optimized. Methods for assembling an implantable medical device and for forming the capacitor assembly insulative liner are provided.