Patent ID: 8970178
Filing Date: 2015-03-03
Classification: B60L,G01R,H01M,H02J,Y02E,Y02T

Abstract:
1. A method to determine a state of charge of a battery, wherein the battery includes at least two terminals, the method comprising: determining a first indicator of a state of health of the battery during a first charge cycle; correlating the first indicator of the state of health of the battery to a first relationship of an open circuit voltage to an amount of charge in the battery; measuring a voltage at the terminals of the battery; calculating an open circuit voltage of the battery using the voltage measured at the terminals of the battery, a current applied to or removed from the battery and an impedance of the battery; and determining a first state of charge of the battery using (i) the calculated open circuit voltage and (ii) the first relationship of the open circuit voltage to the amount of charge in the battery.