Abstract: A hybrid electric powertrain includes an electrical energy storage device and electric machines. A method for operating the powertrain is disclosed to control the electric machines effective to attain a predetermined state of life profile for the electric energy storage device.

Abstract: A method for predicting change in an operating state, e.g. state of life, for an electrical energy storage device includes establishing a plurality of values for an operating parameter, e.g. current, of the electrical energy storage device and, for each respective value, determining a corresponding change in the operating state for the energy storage device based upon the respective value. Preferably, change in the state of life is determined based upon an integration of electrical current, a depth of discharge of the energy storage device, and an operating temperature factor of the electrical energy storage device.

Abstract: A hybrid vehicular powertrain includes an electrical energy storage device. A method is disclosed effective to account for the effects that temperature during periods of vehicle inactivity has upon the electrical energy storage device.

Abstract: Sate-of-life for an electrical energy storage device is predictively determined based on electrical current, state-of-charge, and temperature of the electrical energy storage device during active and quiescent periods of operation.

Abstract: A method for determining a preferred operating gradient for use in attaining a life objective for an electrical energy storage device in a hybrid vehicle is disclosed. A present state-of-life of the electrical energy storage device is provided and a life target for the electrical energy storage device is established as a predetermined limit in a predetermined metric at a predetermined state-of-life of the electrical energy storage device. A state-of-life gradient is then determined with respect to the predetermined metric which converges the state-of-life of the electrical energy storage device to the life target.

Abstract: A hybrid vehicular powertrain includes an electrical energy storage device. State-of-life for the electrical energy storage device is predictively determined based on electrical current, state-of-charge, and temperature of the electrical energy storage device during active and quiescent periods of operation.

Abstract: A electrical energy storage device may experience quiescent periods of operation. A method is disclosed effective to account for the effects that temperature during quiescent periods has upon the electrical energy storage device.

Abstract: A distributed on-board diagnostic (OBD) architecture for a control system of a vehicle includes a plurality of control modules that are in communication with one another and a designated master OBD control module that is one of the plurality of control modules. The master OBD control module performs functions that a remainder of the plurality of control modules are incapable of performing including at least one of arbitrating a malfunction indicator lamp (MIL) state, arbitrating and storing OBD freeze frame data and determining OBD status flags of the remainder of the plurality of control modules.