Method and system for diagnosis of the internal state of a battery through acoustic emission

A method of estimating an internal state of a first electrochemical system for electrical power storage wherein at least one property relative to the internal state of the first electrochemical system is estimated from acoustic emission measurements, comprising:

• measuring for different internal states of at least a second electrochemical system of identical type as the first electrochemical system an acoustic emission response from the second electrochemical system corresponding to each internal state;
• recording for each acoustic emission response a signal characteristic of the acoustic emission response from the second system;
• processing the recorded signals characteristic of the second system by grouping the signals into populations of signals having common parameters;
• determining an acoustic signature of an internal state of the second electromechanical system by calibrating a relationship between at least one of the parameters common to at least one acoustic signal population and an internal state of the second electromechanical system by an analysis of values of at least one common parameter of the acoustic signal populations obtained for each of the internal states;
• obtaining an acoustic emission response from the first electrochemical system to obtain at least one signal characteristic of the acoustic emission measurements from the first system;
• and
• estimating the internal state of the first electrochemical system from the relationship by detecting at least one parameter characteristic of an acoustic signature of an internal state in the signal characteristic of the acoustic emission response from the first system.