Abstract: A system includes a plurality of batteries, first and second relays, a relay control module, and a welding indication module. The batteries are electrically connected and collectively output power for an electric motor via first and second nodes. The first relay is connected between a first output of the batteries and the first node. The second relay is connected between a second output of the batteries and the second node. The relay control module controls the first and second relays. The welding indication module commands the relay control module to open the first relay during a diagnosis period, commands the relay control module to close the second relay during the diagnosis period, and indicates whether the first relay is welded closed based on a voltage between the first and second nodes during the diagnosis period.

Abstract: A battery control module for a battery system includes a pulse-width modulation (PWM) module that generates N PWM signals. The battery control module also includes a contactor control module that consecutively applies the N PWM signals to close a contactor in order to connect a battery to a load. Application of a first one of the N PWM signals moves the contactor at a first velocity from an open position and application of a second one of the N PWM signals moves the contactor at a second velocity to a closed position. The first velocity is less than the second velocity. N is an integer greater than one.

Abstract: A battery control module for a battery system includes a pulse-width modulation (PWM) module that generates N PWM signals. The battery control module also includes a contactor control module that consecutively applies the N PWM signals to close a contactor in order to connect a battery to a load. Application of a first one of the N PWM signals moves the contactor at a first velocity from an open position and application of a second one of the N PWM signals moves the contactor at a second velocity to a closed position. The first velocity is less than the second velocity. N is an integer greater than one.