Method for detecting a motor vehicle overweight state, and method for managing the charge of a traction battery

A method for managing a charge of a traction battery of a motor vehicle, comprising:

• detecting a possible state of excessive weight of the vehicle;
• and
• increasing, when the state of excessive weight is detected, an energy level stored in the traction battery to a charge threshold to respond to temporary vehicle rolling situations,
• wherein the detecting includes
• selecting a determined number of phases of longitudinal acceleration of the vehicle, for each of which the longitudinal acceleration is greater than a longitudinal acceleration threshold value;
• and
• for each selected longitudinal acceleration phase:
• calculating an average value of a differential force which is equal to a value of traction efforts of a power train from which are subtracted a value of a resultant longitudinal acceleration force of the vehicle and a value of a sum of resisting efforts to which the vehicle is subjected while rolling,
• calculating a statistical value from the calculated average values of the differential force, and
• comparing the calculated statistical value with a threshold value of excessive weight of the vehicle,
• wherein the vehicle is in a state of excessive weight when the statistical value is greater than the threshold value of excessive weight of the vehicle.