Patent ID: 8170818
Filing Date: 2012-05-01
Classification: G01R

Abstract:
1. A method for determining parameters of a battery, said method comprising: defining an equivalent circuit model of the battery that includes a battery open circuit voltage, a battery ohmic resistance and an RC pair including an RC pair voltage, an RC pair resistance and an RC pair capacitance; defining a first sampling rate and a second sampling rate where the first sampling rate is faster than the second sampling rate; sampling a battery terminal voltage, a battery terminal current and a battery temperature at the first sampling rate; defining a battery terminal voltage relationship; defining an RC voltage relationship; using the battery terminal voltage relationship and the RC pair voltage relationship to determine a battery dynamics relationship including a plurality of first coefficients; regressing the battery dynamics relationship to obtain the plurality of first coefficients; determining the battery open circuit voltage and the battery ohmic resistance using the plurality of first coefficients; determining the battery state of charge using the battery open circuit voltage and the sampled battery temperature; re-sampling the battery terminal voltage, the battery terminal current and the battery temperature at the second sampling rate; re-calculating the RC pair voltage at the second sampling time; regressing the re-calculated RC pair voltage to obtain a plurality of second coefficients; estimating the RC pair resistance and capacitance using the plurality of second coefficients; and determining a predicted power of the battery over a certain time period using the open circuit voltage, the ohmic resistance, the RC pair resistance and the RC pair capacitance.