Surgical instrument battery pack with voltage polling

A power device configured to provide power to a medical device, comprising:

• (a) a housing, wherein the housing is removably attachable to a medical device;
• (b) a battery supported by the housing;
• (c) an electrical connection feature configured to electrically couple with a complementary connection feature of the medical device;
• (d) a sensor operable to sense a characteristic of the medical device;
• and
• (e) a processor in communication with the sensor, wherein the processor is operable to identify the medical device based on the sensed characteristic, wherein the processor is further operable to change a polarity of the electrical connection feature based on the identification.

A power device configured to provide power to a medical device, comprising:

• (a) a housing, wherein the housing is removably attachable to a medical device;
• (b) a battery supported by the housing;
• (c) an electrical connection feature configured to electrically couple with a complementary connection feature of the medical device;
• (d) a sensor operable to sense a characteristic associated with the medical device;
• and
• (e) a processor in communication with the sensor, wherein the processor is operable to change a polarity of the electrical connection feature based on the sensed characteristic.