Abstract: A vehicle includes a traction battery. The vehicle further includes a controller programmed to generate a capacity estimate of the traction battery and, in response to an amount of energy supplied to the traction battery during a charge cycle being less than an estimated amount of energy stored in the traction battery during the charge cycle, detect that the capacity of the traction battery has changed and alter an operating strategy of the traction battery until the capacity estimate is updated.

Abstract: Lithium ion battery state of charge (SOC) is a function of open circuit voltage (OCV). Battery internal diffusion process needs to be nearly completed to be able to measure battery open circuit voltage. The length of the minimum settling time depends on the battery type, usage and temperature. Described are methods to determine electric vehicle battery voltage relaxation time based on battery temperature and usage history.

Abstract: A vehicle includes a battery pack, an electric motor, and a contactor to electrically connect the pack and motor. The contactor is configured with a control circuit to electrically connect the pack and motor. The control circuit includes a leak detection sensor. The vehicle further includes a controller to output a leakage resistance associated with the pack. The leakage resistance is based on a voltage of the pack and a leak voltage detected by the sensor while the contactor is closed.

Abstract: Lithium ion battery state of charge (SOC) is a function of open circuit voltage (OCV). Battery internal diffusion process needs to be nearly completed to be able to measure battery open circuit voltage. The length of the minimum settling time depends on the battery type, usage and temperature. Described are methods to determine electric vehicle battery voltage relaxation time based on battery temperature and usage history.

Abstract: Lithium ion battery state of charge (SOC) is a function of open circuit voltage (OCV). Battery internal diffusion process needs to be nearly completed to be able to measure battery open circuit voltage. The length of the minimum settling time depends on the battery type, usage and temperature. Described are methods to determine electric vehicle battery voltage relaxation time based on battery temperature and usage history.

Abstract: A battery management system for a vehicle includes a controller programmed to charge a battery at a predetermined charge current. The controller activates an electrical load to discharge the battery for a predetermined time in response to a charge current of the battery becoming less than the predetermined charge current at a predetermined voltage limit. After discharging for the predetermined time, the controller resumes charging at the predetermined charge current. A current magnitude during the discharge and the predetermined time may be based on factors including the predetermined charge rate, a battery temperature, and a charge current magnitude during charging.

Abstract: Vehicles that use electric power as a motive force may use accurate measurements of battery power for numerous purposes, e.g., battery characteristics, state of charge of the battery, travel distance remaining for the vehicle and the like. A traction battery measurement should be taken when the battery is fully relaxed, i.e., the battery is neither being charged nor providing power and a time period thereafter when the battery chemistry reaches a steady state. A controller or methods may determine if the battery is relaxed and if the battery is not relaxed, delay charging or discharging of the traction battery to allow accurate battery capacity determination. The controller may control a battery charger to ensure the battery is fully relaxed before sensing battery characteristics.

Abstract: A current sensor fault detection system is disclosed which enables detection of a current sensor fault while the current sensor is operating and providing a current sensor output which is within a normal operating range. The current sensor is monitored by at least one controller which compares a change in battery state of charge error with a predetermined threshold. The change in battery state of charge error is a difference between a first change in battery state of charge calculated by integrating battery current with respect to a time and a second change in battery state of charge calculated based on the battery open circuit voltage during the time.

Abstract: A diagnostic method for contact resistance failure includes estimating electrical contact surface resistance of at least one contactor, determining a faulted status of the at least one contactor and indicating the faulted status of the at least one contactor if the at least one contactor is in the faulted status.

Abstract: Systems and methods for operating a battery pack supplying power to propel a vehicle are disclosed. One example method comprises, determining a difference between an estimated battery pack temperature and a sensed battery pack temperature as a basis for adjusting battery pack output power. The method also includes adjusting a speed of a cooling fan based on the difference between estimated battery pack temperature and sensed battery pack temperature.

Abstract: A vehicle includes a traction battery and a controller. The controller is programmed to detect a voltage measurement error associated with a battery cell. The controller is also programmed to, in response to detecting a voltage measurement error for a battery cell, initialize a state of charge of the battery cell according to an average change in stored capacity between power cycles.

Abstract: A vehicle includes a traction battery. The vehicle further includes a controller programmed to generate a capacity estimate of the traction battery and, in response to an amount of energy supplied to the traction battery during a charge cycle being less than an estimated amount of energy stored in the traction battery during the charge cycle, detect that the capacity of the traction battery has changed and alter an operating strategy of the traction battery until the capacity estimate is updated.

Abstract: A battery management system for a vehicle includes a controller programmed to charge a battery at a predetermined charge current. The controller activates an electrical load to discharge the battery for a predetermined time in response to a charge current of the battery becoming less than the predetermined charge current at a predetermined voltage limit. After discharging for the predetermined time, the controller resumes charging at the predetermined charge current. A current magnitude during the discharge and the predetermined time may be based on factors including the predetermined charge rate, a battery temperature, and a charge current magnitude during charging.

Abstract: A leakage detection system for a battery pack of a vehicle may include detection circuitry having a first side connecting a positive terminal of the pack to ground and a second side connecting a negative terminal of the pack to ground, and including no more than one switch among the sides. The system may also include measurement circuitry configured to measure a voltage across a resistor of one of the sides when the switch is open and closed, and a controller programmed to output a leakage associated with the battery pack based on the voltage.

Abstract: A vehicle includes a traction battery and a controller. The controller is programmed to detect a voltage measurement error associated with a battery cell. The controller is also programmed to, in response to detecting a voltage measurement error for a battery cell, initialize a state of charge of the battery cell according to an average change in stored capacity between power cycles.

Abstract: Systems and methods for operating a battery pack supplying power to propel a vehicle are disclosed. One example method comprises, adjusting a battery pack state of charge window in response to vehicle mass. Adjusting the battery pack state of charge window in response to vehicle mass may allow the battery pack to provide an increased amount of energy to a motor so that the motor may provide torque to a driveline for a longer period of time and/or absorb more vehicle generator produced power during vehicle operations.

Abstract: A battery management system for a vehicle includes a controller programmed to apply a current pulse to reverse a current flow through a battery to reduce or remove cell polarization. After the current pulse, an open-circuit voltage is measured as the terminal voltage of the battery. The settling time for the terminal voltage to approach the open-circuit voltage is reduced after the current pulse. The magnitude of the current pulse is based on a battery state of charge, a battery temperature, and a current magnitude prior to the current pulse.

Abstract: Systems and methods for operating a battery pack supplying power to propel a vehicle are disclosed. One example method includes, increasing a battery pack state of charge window in response to a negative grade of a section of road a vehicle is traveling. The method also includes decreasing the battery pack state of charge window in response to the vehicle transitioning from traveling down a section of road having a negative grade to traveling down a section of road that has a positive or zero grade.

Abstract: A vehicle may include a traction battery, a harness electrically connected with the battery, and a controller programmed to generate harness anomaly output based on data indicative of historical resistances associated with the harness and temperature and state of charge data for the battery indicative of a current resistance associated with the harness.

Abstract: Vehicles that use electric power as a motive force may use accurate measurements of battery power for numerous purposes, e.g., battery characteristics, state of charge of the battery, travel distance remaining for the vehicle and the like. A traction battery measurement should be taken when the battery is fully relaxed, i.e., the battery is neither being charged nor providing power and a time period thereafter when the battery chemistry reaches a steady state. A controller or methods may determine if the battery is relaxed and if the battery is not relaxed, delay charging or discharging of the traction battery to allow accurate battery capacity determination. The controller may control a battery charger to ensure the battery is fully relaxed before sensing battery characteristics.