An electrical apparatus including a battery module and a battery verification module is disclosed. The battery module has a verification circuit and an identification resistor. When the battery module is connected to the battery verification module, the battery verification module obtains a type information of the battery module according to the voltage level on a coupled point between a reference resistor and the identification resistor. The battery verification module transmits a verification request to the verification circuit to allow the verification circuit to transmit a verification signal to the battery verification module through a coupled path between the reference resistor and the identification resistor. The reference resistor is built in the battery verification module.