NOVELTY - The device comprises an integrated circuit comprising: a voltage monitoring circuit for measuring open circuit voltages of an electrochemical cell (108), where the voltages are generated upon charging or discharging of the cell or stopping charging or discharging of the cell; a temperature monitoring circuit measuring a set of temperatures of the electrochemical cell, where the temperatures are generated upon charging or discharging of the cell or stopping charging or discharging of the cell; and a current monitoring circuit measuring a charging current or a discharging current of the cell.    USE - The device is useful for determining a condition such as thermodynamic parameter, a state of charge, a state of health, a state of safety and a cycle number, of an electrochemical cell in an automobile and a portable electronic device (all claimed), where the electrochemical cell is a primary battery, a secondary battery, a galvanic cell, a fuel cell and a photovoltaic cell, the automobile is an electric vehicle and a hybrid electric vehicle, and the electronic device is a personal computer, a laptop, a cell phone, a tablet computer, an electronic-book reader, a portable music player, a portable audio player, a portable video player, a bar code reader, a telemetric reader, a portable light device, a portable sound or alarm device, and a portable autonomous electric power devices for military, telecommunications, aerospace and space applications, a watch, a clock, a portable medical device, and an implantable medical device.    ADVANTAGE - The highly versatile device monitors selected electrochemical cell conditions and carries out measurements of number of cell parameters with high accuracy to allow for precise determination of thermodynamic state functions and materials properties relating to the composition, phase, states of charge, health and safety and electrochemical properties of electrodes and electrolytes in the electrochemical cell, and provides information for predicting a wide range of performance attributes for any electrochemical system having an electrode pair.    DETAILED DESCRIPTION - The device comprises an integrated circuit comprising: a voltage monitoring circuit for measuring open circuit voltages of an electrochemical cell (108), where the voltages are generated upon charging or discharging of the cell or stopping charging or discharging of the cell; a temperature monitoring circuit measuring a set of temperatures of the electrochemical cell, where the temperatures are generated upon charging or discharging of the cell or stopping charging or discharging of the cell; a current monitoring circuit measuring a charging current or a discharging current of the cell; and a circuit determining a thermodynamic parameter of the cell, where the parameter is one of a change in entropy of the cell, a change in enthalpy of the cell and a change in free energy of the electrochemical cell. The thermodynamic parameter determining circuit is positioned in electrical or data communication with the temperature monitoring circuit to receive temperature measurements from the monitoring circuit, positioned in electrical or data communication with the voltage monitoring circuit to receive open circuit voltage measurements from the voltage monitoring circuit and positioned in electrical or data communication with the current monitoring circuit to receive current measurements from the current monitoring circuit or to provide thermodynamics parameters to the current monitoring circuit. The device further comprises temperature sensor positioned in thermal communication with the electrochemical cell and further positioned in electrical or data communication with the temperature monitoring circuit. INDEPENDENT CLAIMS are included for:    (1) a method for determining a condition of an electrochemical cell; and    (2) a method for safely operating an electrochemical cell.    DESCRIPTION OF DRAWING(S) - The figure shows a block diagram of an electrochemical thermodynamic measurement system.    Input/output circuit (103)    Display circuit (105)    Sub-circuit (106)    Command circuit (107)    Electrochemical cell. (108)