The Beijing Fire Department reported an incident in the Daxing District where a parked private vehicle caught fire. Firefighters arrived at the scene to extinguish the flames after smoke was observed coming from the car interior.
Investigators determined that the fire was caused by an employee access card left on the vehicle's wireless charging pad. The card, which contained metal components like chips and antennas, interacted with the charging coils.
The wireless charging system uses electromagnetic induction, creating a strong alternating magnetic field. When metal-containing items are placed in this area, they generate eddy currents, similar to the heating process of an induction cooktop.
The plastic casing of the card could not dissipate the heat generated by these currents. This rapid accumulation of heat caused the card to overheat, deform, and eventually smoke and ignite, posing a significant fire risk to the vehicle.
Fire authorities warn drivers against placing cards with chips or antennas, such as bank cards, ID cards, or access passes, on wireless charging pads. These items should be kept away from areas with strong magnetic fields to prevent potential accidents.
