Implantable cardioverter defibrillator with switchable power source and patient warning system cardiac device

摘要

A system and method are provided for using a multiple cell power supply in an implantable medical device such as an implantable cardioverter defibrillator. In a two-cell battery network, a higher energy density cell continuously charges a lower density cell, and the lower density cell provides the current needed for device functions. A current sensor detects the current flowing between the two cells. If the current deviates from an acceptable normal range, one battery cell is failing. The battery network is then reconfigured by opening and closing intervening switches such that the failing cell is eliminated and the remaining cell continues to power device functions. Upon eliminating a failing battery cell, a patient warning signal is issued.