Battery depth of discharge in an implantable device

Systems and methods for determining depth of discharge for implantable device batteries are provided. One aspect of this disclosure relates to a method for determining depth of discharge for a battery in an implantable medical device. Voltage recovery of the battery is measured subsequent to a predetermined event. Measured voltage recovery data is stored in a database adapted to store data for one or more devices. Measured voltage recovery data is compared with stored voltage recovery data to determine battery depth of discharge. According to various embodiments, battery capacity consumed is measured using a coulometer and using a capacity-by-voltage device. Measured battery capacity consumed is combined with measured voltage recovery data using a predetermined weighted average, and the combined data is stored in the database. The stored data is used to determine battery depth of discharge, according to an embodiment.