A power interface control device for an electric or hybrid vehicle, said electric or hybrid vehicle comprising: - an electric power network; - a transmission and - an electric motor (EM1, EM2) mechanically associated with said transmission and electrically associated with said electric power network, and - a propulsion battery operatively connected to said electric power network to supply said electric motor; - a first and a second positive and negative electrical conductors (BB1, BB2) interposed between said propulsion battery and said electric power network, wherein a first and a second electrical switch (INT1, INT2) are respectively arranged on said first and second electrical conductors, said switches defining a power interface between said propulsion battery and said electric power network; Characterized in that a power interface control device is provided, said power interface control device comprising at least: - first four potential ports to carry out at least first three potential differential measurements (V0, V1, V2); - a first current sensor to carry out a first measurement of the current passing through one of said electrical conductors (BB1, BB2) of said power interface; - first actuation means to control the opening and closing of the first pair of electrical switches (INT1, INT2) of said power interface; - processing means configured for: • acquiring said differential measurements and said current measurement, • controlling said actuation means, and comprising interface means (DATA BUS) to allow an operational interfacing between said processing means and a vehicle data network, - a closed container, made of insulating material, comprising at least said four ports and containing said first current sensor, said actuation means and said processing means as well as connection means to allow a mechanical coupling between the container and said electrical conductor, said power interface control device being mechanically connected to one of said first or second electrical conductors (BB1, BB2) and having said first four potential ports electrically connected upstream and downstream of each of said first and second switches (INT1, INT2) to detect any opening and closing thereof. - an electric power network; - a transmission and - an electric motor (EM1, EM2) mechanically associated with said transmission and electrically associated with said electric power network, and - a propulsion battery operatively connected to said electric power network to supply said electric motor; - a first and a second positive and negative electrical conductors (BB1, BB2) interposed between said propulsion battery and said electric power network, wherein a first and a second electrical switch (INT1, INT2) are respectively arranged on said first and second electrical conductors, said switches defining a power interface between said propulsion battery and said electric power network; - first four potential ports to carry out at least first three potential differential measurements (V0, V1, V2); - a first current sensor to carry out a first measurement of the current passing through one of said electrical conductors (BB1, BB2) of said power interface; - first actuation means to control the opening and closing of the first pair of electrical switches (INT1, INT2) of said power interface; - processing means configured for: • acquiring said differential measurements and said current measurement, • controlling said actuation means, and comprising interface means (DATA BUS) to allow an operational interfacing between said processing means and a vehicle data network, • acquiring said differential measurements and said current measurement, • controlling said actuation means, - a closed container, made of insulating material, comprising at least said four ports and containing said first current sensor, said actuation means and said processing means as well as connection means to allow a mechanical coupling between the container and said electrical conductor,