A method for monitoring the safety of a rechargeable Li-ion battery "LIB", the method comprising the procedures of: determining an initial electrical state of said LIB, the initial electrical state relating to at least one of: a voltage; a current; and a charging/discharging related state or parameter of said LIB; altering the electrical state of said LIB by the application or removal of a direct current "DC" electrical stimulus to said LIB so as to trigger a time-varying response; measuring the time-varying response of said LIB to the altered electrical state; and extracting at least one primary response parameter associated with the functional form of the measured response, said primary response parameter selected from the list consisting of: at least one voltage response value along a voltage response profile; at least one current response value along a current response profile; and at least one parameter relating to the electrical state altering, characterized in that the method further comprises the procedures of: deriving at least one secondary response parameter from said primary response parameter, said secondary response parameter derived by applying at least one mathematical operation to any combination of the at least one primary response parameter and at least one stimulus parameter; and determining a likelihood of a short circuit precursor condition, in accordance with at least said secondary response parameter. determining an initial electrical state of said LIB, the initial electrical state relating to at least one of: a voltage; a current; and a charging/discharging related state or parameter of said LIB; altering the electrical state of said LIB by the application or removal of a direct current "DC" electrical stimulus to said LIB so as to trigger a time-varying response; measuring the time-varying response of said LIB to the altered electrical state; and extracting at least one primary response parameter associated with the functional form of the measured response, said primary response parameter selected from the list consisting of: at least one voltage response value along a voltage response profile; at least one current response value along a current response profile; and at least one parameter relating to the electrical state altering, characterized in that the method further comprises the procedures of: deriving at least one secondary response parameter from said primary response parameter, said secondary response parameter derived by applying at least one mathematical operation to any combination of the at least one primary response parameter and at least one stimulus parameter; and determining a likelihood of a short circuit precursor condition, in accordance with at least said secondary response parameter. deriving at least one secondary response parameter from said primary response parameter, said secondary response parameter derived by applying at least one mathematical operation to any combination of the at least one primary response parameter and at least one stimulus parameter; and determining a likelihood of a short circuit precursor condition, in accordance with at least said secondary response parameter. <EOS>