Abstract: A system and associated method are described for balancing an electrical parameter associated with stored electric power in a multi-cell battery. A cell charge balancing system determines a first plurality of the electrical parameters associated with respective ones of the plurality of cells, a plurality of first charge parameters associated with the cells, and a first quality index. A second plurality of the electrical parameters are determined, and second charge parameters are determined to determine a second quality index. The first and second quality indices are compared, and a cell charge balancing routine controls the balancing system based upon the first quality index when the first quality index is greater than the second quality index. The cell charge balancing routine controls the cell charge balancing system based upon the second quality index when the first quality index is less than the second quality index.

Abstract: System and method of controlling operation of a device having multiple rechargeable packs configured to store energy. The multiple rechargeable packs include at least one primary pack characterized by a first capacity and at least one auxiliary pack characterized by a second capacity, the first capacity being greater than the second capacity. A controller is configured to selectively command one or more of the multiple rechargeable packs to begin at least one of discharging and charging. When an estimated end of trip time is less than or equal to a discharging time of the at least one auxiliary pack, the discharging of the at least one auxiliary pack is begun. When the estimated end of trip time is greater than the discharging time, the discharging is delayed until the respective state of charge of the at least one primary pack reaches a first threshold.

Abstract: Powerflow of a rechargeable energy storage system (RESS) is managed according to a method. The RESS has series-connected first and second battery elements with different characteristics. Each element, e.g., a pack, has a corresponding maximum or minimum voltage or current limit. Currents are predicted for each of the first and second battery elements via a controller using a corresponding voltage limit. A requested operating mode of the RESS is used to select a current for the elements. A voltage across the elements is predicted using the selected current and a corresponding battery state space model. The method predicts a total power capability of the RESS over a prediction horizon using the selected current to generate predicted power capability values. The requested operating mode is controlled over the horizon using the power capability values. A powertrain system includes the RESS, an inverter, an electric machine, and the controller.

Abstract: Powerflow is managed using a method, e.g., in a powertrain system having a multi-pack rechargeable energy storage system (RESS) with parallel battery packs. Each pack has a corresponding maximum electrical (current or voltage) limit. The method includes predicting a corresponding terminal voltage for each pack using the corresponding maximum electrical limit. The method includes selecting a terminal voltage as a selected voltage based on a requested operating mode, including selecting a maximum of the terminal voltages when the requested operating mode is a discharging mode and a minimum of the same when the requested operating mode is a charging mode. A pack current through each pack is predicted using the selected voltage and a corresponding battery state space model. A total power capability of the RESS is predicted over a predetermined prediction horizon using the selected voltage, with the operating mode controlled over the prediction horizon via the controller.

Abstract: Presented are traction battery pack balancing systems, methods for making/operating such systems, and multi-pack, electric-drive motor vehicles with battery pack balancing capabilities.

Abstract: A method for estimating remaining energy in a battery pack having series-connected cells/cell groups includes measuring battery parameters, including a battery voltage, current, and temperature. The controller estimates a static state of charge difference ( ?SOC) value and a current-dependent ?SOC value in real-time using the parameters, including calculating the static ?SOC value as a difference between an average SOC of the battery pack and an SOC of a weakest/lowest energy cell group. The current-dependent ?SOC value is a percentage SOC per unit of the current. The static ?SOC value and current-dependent ?SOC values are filtered via a multi-parameter state estimator block. Using the filtered state values, the controller executes a control action responsive to the estimated remaining energy, including displaying the remaining energy and/or a quantity derived from the remaining energy via a display device. A powertrain system includes the controller, electric machine, and battery pack.