Method for estimating a state of health of an energy storage system of a vehicle, wherein the method includes the following steps: i) acquiring information about the energy storage system; ii) evaluating the acquired information while taking into account predefined boundary conditions, wherein the predefined boundary conditions correspond to previously specified vehicle function data and/or model vehicle data; and iii) estimating the state of health of the energy storage system, wherein vehicle function data are recorded for acquiring the information about the energy storage system, wherein a function change, specifically an occurrence, an absence or a function restriction, of at least one vehicle function is concluded or can be concluded from the vehicle function data, and wherein the vehicle function data comprise data concerning the fulfilment/non-fulfilment of at least one vehicle function, specifically data concerning switching off and/or switching on of a combustion engine of the vehicle in a start-stop mode of the combustion engine, and wherein the vehicle function data also comprise data concerning the operation of at least one functional component or safety component and data concerning the operation of at least one comfort component, wherein the data concerning the operation of at least one functional component or safety component are the following data: - data concerning the operation of a radiator of an engine of the vehicle, internal lighting, external lighting, power steering, power braking, a gearbox, a clutch, technical driving safety systems and/or riding stability control systems, and/or driving dynamics management systems; and wherein the data concerning the operation of at least one comfort component are the following data: - data concerning the operation of an air-conditioning system, heating, an audio/video entertainment system and/or a navigation system, wherein the state of health of the energy storage system is estimated on the basis of the acquired information about the energy storage system without taking into account directly or indirectly measured values of a capacitance, charge, voltage, and/or a current of the energy storage system, wherein, to estimate the acquired information, the vehicle function data are compared with the previously specified vehicle function data and/or the model vehicle data. i) acquiring information about the energy storage system; ii) evaluating the acquired information while taking into account predefined boundary conditions, wherein the predefined boundary conditions correspond to previously specified vehicle function data and/or model vehicle data; and iii) estimating the state of health of the energy storage system, wherein vehicle function data are recorded for acquiring the information about the energy storage system, wherein a function change, specifically an occurrence, an absence or a function restriction, of at least one vehicle function is concluded or can be concluded from the vehicle function data, and wherein the vehicle function data comprise data concerning the fulfilment/non-fulfilment of at least one vehicle function, specifically data concerning switching off and/or switching on of a combustion engine of the vehicle in a start-stop mode of the combustion engine, and wherein the vehicle function data also comprise data concerning the operation of at least one functional component or safety component and data concerning the operation of at least one comfort component, wherein the data concerning the operation of at least one functional component or safety component are the following data: - data concerning the operation of a radiator of an engine of the vehicle, internal lighting, external lighting, power steering, power braking, a gearbox, a clutch, technical driving safety systems and/or riding stability control systems, and/or driving dynamics management systems; and - data concerning the operation of a radiator of an engine of the vehicle, internal lighting, external lighting, power steering, power braking, a gearbox, a clutch, technical driving safety systems and/or riding stability control systems, and/or driving dynamics management systems; and wherein the data concerning the operation of at least one comfort component are the following data: - data concerning the operation of an air-conditioning system, heating, an audio/video entertainment system and/or a navigation system, - data concerning the operation of an air-conditioning system, heating, an audio/video entertainment system and/or a navigation system, wherein the state of health of the energy storage system is estimated on the basis of the acquired information about the energy storage system without taking into account directly or indirectly measured values of a capacitance, charge, voltage, and/or a current of the energy storage system, wherein, to estimate the acquired information, the vehicle function data are compared with the previously specified vehicle function data and/or the model vehicle data.