Methods and systems for thermodynamic evaluation of battery state of health

摘要

Described are systems and methods for accurately characterizing thermodynamic and materials properties of electrodes and battery systems and for characterizing the state of health of electrodes and battery systems. Measurement of physical attributes of electrodes and batteries corresponding to thermodynamically stabilized electrode conditions permit determination of thermodynamic parameters, including state functions such as the Gibbs free energy, enthalpy and entropy of electrode/electrochemical cell reactions, that enable prediction of important performance attributes of electrode materials and battery systems, such as energy, power density, current rate, cycle life and state of health. Also provided are systems and methods for charging a battery according to its state of health.

主权项

1. A method of charging an electrochemical cell comprising a host material, the method comprising the steps of:
characterizing the state of health of the electrochemical cell; selecting a charging voltage, current or voltage and current according to the characterized state of health of the electrochemical cell; and providing the selected voltage, current or voltage and current to electrodes of the electrochemical cell to charge the electrochemical cellwherein the step of characterizing the state of health of the electrochemical cell comprises the steps of:
determining a change in Gibbs Free Energy (ΔG), a change in Entropy (ΔS), a change in Enthalpy (ΔH) or any combination thereof of the electrochemical cell for a plurality of selected electrochemical cell compositions; determining states of charge of the electrochemical cell for each of the plurality of selected electrochemical cell compositions; identifying the states of charge and ΔG, ΔS, ΔH or any combination thereof corresponding to an event or condition of the electrochemical cell; and comparing the ΔG, ΔS, ΔH or any combination thereof corresponding to the event or condition of the electrochemical cell to reference ΔG, ΔS, ΔH or any combination thereof corresponding to the event or condition of a reference electrochemical cell.