The primary objective of this research effort are to enhance the power density capabilities of the lithium iodine (PZVP) battery system and to provide an in-depth understanding of the role of the cathode in the battery rate limiting mechanism particularly with respect to discharge current. The plan of research is as follows. First the batteries will be fabricated employing the new cathode preparation procedure. General discharge behavior at low rates will be determined for comparison to conventional batteries. High rate discharge performance will then be evaluated. In order to evaluate the effectiveness of the cathode modification a number of methods will be utilized. Laser holographic interferometry and electrochemical impedance spectroscopy will be used in-situ to monitor the uniformity of discharge and the lithium iodide electrolyte conductivity respectively. Post-test scanning electron microscopy will be employed to determine the influence of the modification on discharte product formation and correlation with in- situ testing results. Depending on the results obtained further cathode preparation modifications may be included. Potentially an order of magnitude increase in power delivery capability is attainable by modifying cell chemistry and manufacturing procedure. This enhanced battery system could find new application in a broader class of implant devices including multi-input/output programmable pacemakers, implantable defibrillators, implantable drug delivery systems as well as other important industrial and deep space applications.
