B737-800
Flight Crew Air Transport Pilot (ATP)
Situational Awareness
Aircraft Equipment Problem Less Severe
General Maintenance Action
Human Factors
During cruise flight; I was replacing the batteries in my headset and dropped a 3 pack of AAA batteries wrapped in a rubber band. The batteries bounced off the cockpit floor; hit the toe of my boot; and bounced into the [underfloor area] under the First Officer's left rudder pedal. Notified Dispatch and put a write-up in the logbook. I met the Mechanic after landing and spent the next hour with flashlight trying to find missing batteries. Watch when you drop stuff on cockpit floor; it could go anywhere. Right now; no batteries found.
B737-800 First Officer reported he dropped some AAA batteries that went under the floor in the rudder pedal area.