Accurate state of charge assessment of lithium-manganese dioxide primary batteries

摘要

A new method for state of charge (SOC) assessment of Li/MnO2 primary batteries is disclosed. The method is based on thermodynamics data measurements and processing. Entropy 'Delta S' and enthalpy 'Delta H' data are collected during intermittent discharge process and tentatively linked to SOC. Using Li/MnO2 cell sets from two different manufacturers, we found a linear relationship between SOC, Delta S and Delta H; i.e. SOC = alpha+beta Delta S+lambda Delta H. In the equation alpha, beta and lambda coefficients are manufacturer dependent. This result has been assigned to the physical chemical characteristics MnO2, which vary according the cathode material synthesis conditions specific to each manufacturer.