Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Communication Breakdown
Deviation / Discrepancy - Procedural Hazardous Material Violation; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Passenger Electronic Device; Flight Deck / Cabin / Aircraft Event Passenger Misconduct
Flight Crew Overcame Equipment Problem; General Flight Cancelled / Delayed; General Maintenance Action
Human Factors
During passenger loading; ramp crew received a motorized wheelchair/scooter for an elderly passenger. The passenger declared that the scooter had a dry cell battery and the key was removed. Ramp agents filled out air carrier battery powered wheelchair form mobility device tag and gave the flight deck crew a copy.  Upon receiving this form and observing the type of chair through the cockpit window I became suspicious that this particular type of scooter probably contained a lithium ion battery and the tag was improperly labeled based on the passengers assumption.  The flight attendant also made a similar remark and I wanted to exercise caution before the scooter was loaded into the baggage compartment. We decided to have ramp personnel take the scooter out of the baggage compartment and with the assistance of the passenger open motorized mobility device to ascertain the actual type of battery. Upon opening the device we discovered it did have a lithium ion battery with 25.2 V and 11.5 a/h. Based on the formula the battery had less than 300 watts maximum for transport.  We elected to remove the battery and transport it in the passenger cabin to ensure we had access do it during flight. A new mobility form was signed indicating there was a lithium ion battery for the mobility device and I made a correction to the CLR [form] indicating the actual battery type.Members of the flight crew were able to spot a potential hidden dangerous good and miss labeled document based on passenger assumption. The flight crew worked with ground personnel to ensure the mobility device was not loaded onto the aircraft until we were able to ascertain the actual type of battery was confirmed and under the appropriate limits prescribed in our dangerous goods manual.
Captain reported a departure delay due to a Dry Cell motorized wheelchair loaded in cargo compartment with incorrect information on the air carrier's Hazmat documents. An uneventful flight completed after flight crew received correct documents.