Energy management device for a Energy storage device, comprising - a energy storage; - one Energy storage management device; - one Energy estimation device and - one range estimation device; wherein the energy storage management device is Capture and Providing a variety in the energy storage available energy storage parameters furnished is wherein the energy estimation device for Receiving the multitude of energy storage parameters and for the Provide an energy estimate from the multitude of energy storage parameters furnished is; wherein the energy estimation device from the provided variety of energy storage parameters in the essential only selects current parameters; where a current parameter is a parameter that affects the current flow in and/ or from the energy storage device a Influence has; wherein the range estimation device is arranged is to convert the energy estimate into a Estimated range (202b', 202b", 202b′′′) and wherein the range estimation device for Converting the energy estimate into the range one Energy-range curve which is expressed in current parameters shown is; through this characterized in that the energy -range curve has a first and one second curve section has; where the second Curve section of the energy-range curve, which in the Area one low existing energy in the Energy storage device is located; with one higher accuracy determined been is when the first Curve section of the energy-range curve, which in the Area one high existing energy in the energy storage device is located; and where the first Curve section to the second curve section adjusted is that the energy-range curve is a continuous Curve forms. - a energy storage; - one Energy storage management device; - one Energy estimation device and - one range estimation device; wherein the energy storage management device is Capture and Providing a variety in the energy storage available energy storage parameters furnished is wherein the energy estimation device for Receiving the multitude of energy storage parameters and for the Provide an energy estimate from the multitude of energy storage parameters furnished is; wherein the energy estimation device from the provided variety of energy storage parameters in the essential only selects current parameters; where a current parameter is a parameter that affects the current flow in and/ or from the energy storage device a Influence has; wherein the range estimation device is arranged is to convert the energy estimate into a Estimated range (202b', 202b", 202b′′′) and wherein the range estimation device for Converting the energy estimate into the range one Energy-range curve which is expressed in current parameters shown is; through this characterized in that the energy -range curve has a first and one second curve section has; where the second Curve section of the energy-range curve, which in the Area one low existing energy in the Energy storage device is located; with one higher accuracy determined been is when the first Curve section of the energy-range curve, which in the Area one high existing energy in the energy storage device is located; and where the first Curve section to the second curve section adjusted is that the energy-range curve is a continuous Curve forms. wherein the energy storage management device is Capture and Providing a variety in the energy storage available energy storage parameters furnished is wherein the energy estimation device for Receiving the multitude of energy storage parameters and for the Provide an energy estimate from the multitude of energy storage parameters furnished is; wherein the energy estimation device from the provided variety of energy storage parameters in the essential only selects current parameters; where a current parameter is a parameter that affects the current flow in and/ or from the energy storage device a Influence has; wherein the range estimation device is arranged is to convert the energy estimate into a Estimated range (202b', 202b", 202b′′′) and wherein the range estimation device for Converting the energy estimate into the range one Energy-range curve which is expressed in current parameters shown is; through this characterized in that the energy -range curve has a first and one second curve section has; where the second Curve section of the energy-range curve, which in the Area one low existing energy in the Energy storage device is located; with one higher accuracy determined been is when the first Curve section of the energy-range curve, which in the Area one high existing energy in the energy storage device is located; and where the first Curve section to the second curve section adjusted is that the energy-range curve is a continuous Curve forms.