The measurement of electrochemical noise of a Li-ion battery during charge-discharge cycling

Abstract

For the first time electrochemical noise of a commercial Li-ion battery was measured during discharge via a constant value resistor for 1500 cycles. Spectral and statistical analyses were carried out. Both the power spectral density frequency dependence level and noise amplitude were increasing during battery cycling. Distribution diagrams, skewness and kurtosis values demonstrated unchanged normal noise distribution during cycling. Linear dependencies of the current power spectral density values on cycle number were found in the low-frequency band. Dependencies of the power spectral density on the DC-current value were measured at different stages of charge–discharge cycling. The total progress of electrochemical noise growth during cycling was divided into three stages with different prevalent battery degradation types: film growth, active material exfoliation, and structural changes.