Abstract: A system and a method are for estimating an operating parameter value of an energy storage device arranged to provide power for propulsion for an electric or hybrid vehicle. In an embodiment, the method includes determining a first operating parameter value of the energy storage device at a first time; establishing a reference operating parameter value from pre-determined experimental data relating the operating parameter to a time related parameter; and based on the reference operating parameter value and the first operating parameter value, recursively calculating a second operating parameter value of the energy storage device at a second time subsequent to the first time. The recursive calculation includes a tuning parameter for modifying a portion of the reference operating parameter value to be included in the second operating parameter value.

Abstract: Disclosed is a method for determining a value of the state of energy of a rechargeable battery in a vehicle, the battery being connected to an electric consumer; the method including: determining the state of charge as a measure of the present capacity of the battery; and determining the state of energy as an indication of at least the remaining charge and discharge energy of the battery. The disclosed method further includes: calculating and determining the value of the state of energy based on at least one parameter which is related to the operation of the electric consumer and where the at least one parameter varies depending on a mode for operating the vehicle or electric consumer during charging or discharging of the battery. Also disclosed is an arrangement for determining a value of the state of energy of a rechargeable battery in a vehicle.