Method for determining charge state of electric energy storage system i.e. battery of e.g. electric car, involves determining state of charge of battery from maximum dispersion of state of charge

The method involves determining the state of charge of a least charged storage element and the state of charge of a most charged storage element (20). A difference between the state of charge of the most charged storage element and the state of charge of the least charged storage element is determined (22), so as to obtain maximum dispersion of the state of charge. The state of charge of an electric energy storage system i.e. battery is determined (24) from the maximum dispersion of the state of charge. An independent claim is also included for a drivetrain controller of an electric car or a hybrid car. Pour déterminer l'état de charge d'un système de stockage d'énergie électrique d'un véhicule automobile électrique ou hybride, ce système de stockage comportant une pluralité d'éléments de stockage : on détermine (20) l'état de charge de l'élément le moins chargé et l'état de charge de l'élément le plus chargé ; on détermine (22) la différence entre l'état de charge de l'élément le plus chargé et l'état de charge de l'élément le moins chargé, de façon à obtenir la dispersion maximale d'état de charge ; et on détermine (24) l'état de charge du système de stockage à partir de cette dispersion.