Abstract: A battery system includes a battery subpack having first and second battery cells, a cell monitoring circuit, and a subpack microprocessor. The cell monitoring circuit obtains first and second voltage values. A first switch circuit applies an operational voltage to the subpack microprocessor in response to a first control signal from a master controller. The master controller sends a first message that requests the first and second voltage values from the subpack microprocessor. The master controller stops generating the first control signal to induce the first switch circuit to remove the operational voltage from the subpack microprocessor when the master controller does not receive a second message having the first and second voltage values from the subpack microprocessor within a predetermined amount of time after sending the first message.

Abstract: A battery system includes a battery subpack having first and second battery cells, a cell monitoring circuit, a RF transmitter, an RF receiver, a subpack microprocessor, and a first transceiver. The circuit measures a voltage of a first battery cell. The system includes a master controller having a second transceiver. The RF transmitter sends a voltage value corresponding to the voltage of the first battery cell to the RF receiver. The subpack microprocessor determines the first battery cell has an overvoltage condition based on the voltage value and sends an overvoltage message to the master controller via the first and second transceivers. The subpack microprocessor induces first and second subpack contactors to each have an open operational state when the master controller sends an open command to the subpack microprocessor.

Abstract: A battery system includes a battery subpack having first and second battery cells, a cell monitoring circuit, a RF transmitter, an RF receiver, a subpack microprocessor, and a first transceiver. The circuit measures a voltage of a first battery cell. The system includes a master controller having a second transceiver. The RF transmitter sends a voltage value corresponding to the voltage of the first battery cell to the RF receiver. The subpack microprocessor determines the first battery cell has an overvoltage condition based on the voltage value and sends an overvoltage message to the master controller via the first and second transceivers. The subpack microprocessor induces first and second subpack contactors to each have an open operational state when the master controller sends an open command to the subpack microprocessor.

Abstract: A battery system includes a battery subpack having first and second battery cells, a cell monitoring circuit, and a subpack microprocessor. The cell monitoring circuit obtains first and second voltage values. A first switch circuit applies an operational voltage to the subpack microprocessor in response to a first control signal from a master controller. The master controller sends a first message that requests the first and second voltage values from the subpack microprocessor. The master controller stops generating the first control signal to induce the first switch circuit to remove the operational voltage from the subpack microprocessor when the master controller does not receive a second message having the first and second voltage values from the subpack microprocessor within a predetermined amount of time after sending the first message.

Abstract: A battery system includes a battery subpack having first and second battery cells, a cell monitoring circuit, a RF transmitter, an RF receiver, a subpack microprocessor, and a first transceiver. The circuit measures a voltage of a first battery cell. The system includes a master controller having a second transceiver. The RF transmitter sends a voltage value corresponding to the voltage of the first battery cell to the RF receiver. The subpack microprocessor determines the first battery cell has an overvoltage condition based on the voltage value and sends an overvoltage message to the master controller via the first and second transceivers. The subpack microprocessor induces first and second subpack contactors to each have an open operational state when the master controller sends an open command to the subpack microprocessor.

Abstract: A diagnostic system includes a fan control circuit coupled to an electric fan and a microcontroller, and a sense line coupled to the fan control circuit and the microcontroller. The fan control circuit outputs a fan command sense signal at a duty cycle through the sense line to the microcontroller. A tachometer generates a tachometer signal at a frequency indicative of the rotational speed of the electric fan. A fan tachometer circuit receives the tachometer signal and outputs the tachometer sense signal at a frequency to the microcontroller in response to the tachometer signal. The microcontroller sets a second diagnostic flag to an error value indicating that the sense line has impaired operation if the frequency of the tachometer sense signal is within a desired frequency range, and a first diagnostic flag is equal to a first error value.

Abstract: A diagnostic system for a hybrid electric vehicle is provided. The system includes a vehicle controller, a battery management controller, a monitoring circuit, a transistor, a voltage sensor, and an analog-to-digital converter. The vehicle controller sends a first message to the battery management controller indicating an engine crank occurred. The battery management controller sends a second message to the monitoring circuit, and the monitoring circuit induces a transistor to de-energize an electrical relay. The voltage sensor outputs a voltage signal indicative of a voltage being output by the transistor. The analog-to-digital converter outputs a voltage value indicative of the voltage. The battery management controller sets a diagnostic flag to a first non-fault value if the voltage value is less than a threshold voltage value.

Abstract: A diagnostic system for a hybrid electric vehicle is provided. The system includes a vehicle controller, a battery management controller, a monitoring circuit, a transistor, a voltage sensor, and an analog-to-digital converter. The vehicle controller sends a first message to the battery management controller indicating an engine crank occurred. The battery management controller sends a second message to the monitoring circuit, and the monitoring circuit induces a transistor to de-energize an electrical relay. The voltage sensor outputs a voltage signal indicative of a voltage being output by the transistor. The analog-to-digital converter outputs a voltage value indicative of the voltage. The battery management controller sets a diagnostic flag to a first non-fault value if the voltage value is less than a threshold voltage value.

Abstract: A diagnostic system includes a fan control circuit coupled to an electric fan and a microcontroller, and a sense line coupled to the fan control circuit and the microcontroller. The fan control circuit outputs a fan command sense signal at a duty cycle through the sense line to the microcontroller. A tachometer generates a tachometer signal at a frequency indicative of the rotational speed of the electric fan. A fan tachometer circuit receives the tachometer signal and outputs the tachometer sense signal at a frequency to the microcontroller in response to the tachometer signal. The microcontroller sets a second diagnostic flag to an error value indicating that the sense line has impaired operation if the frequency of the tachometer sense signal is within a desired frequency range, and a first diagnostic flag is equal to a first error value.

Abstract: A battery management system includes a microcontroller having first and second applications. The first application transitions a contactor to an open operational position if a first CRC diagnostic flag is equal to a first encoded fault value. The second application transitions the contactor to the open operational position if a second CRC diagnostic flag is equal to a second encoded fault value. The first and second encoded fault values have a Hamming distance of at least four from one another.

Abstract: A battery management system includes a microcontroller having first and second applications. The first application transitions a contactor to an open operational position if a first CRC diagnostic flag is equal to a first encoded fault value. The second application transitions the contactor to the open operational position if a second CRC diagnostic flag is equal to a second encoded fault value.