Material design strategies for energy storage applications can be considered in two major categories: (1) control of structure and composition and (2) material dimensional control such as the implementation of nanomaterials. Characterization of electrochemical properties determines energy content and possible viability for potential application. Equally critical yet more challenging is quantifying the non-Faradaic parasitic reactions of the active materials and the relationship to battery life. Understanding the significant factors associated with battery lifetimes for the implantable cardioverter defibrillator (ICD) is critical for the development of new ICD batteries. In situ dissolution of the cathode material has been identified as a major factor in premature end of life for ICD batteries. This study contains the kinetic analyses of silver and vanadium dissolution from the benchmark silver vanadium oxide (SVO) material and two silver vanadium phosphorous oxide (SVPO-H and SVPO-R) materials with differing physical properties in a non-aqueous ICD battery electrolyte. A comparison of the kinetic and mechanistic results for SVO, SVPO-H and SVPO-R provides insight for future material design approaches.