Patent ID: 9316693
Filing Date: 2016-04-19
CPC Classification: G01R,H01M,Y02E

Claim Text:
1. A method for estimating state of charge (SOC) of an electrochemical cell (E) having a charge profile (PC) in which variation of voltage as a function of state of charge between a state of charge higher than a value MinSOCZone2 of state of charge corresponding to a predetermined voltage VmaxZone1 and a state of charge less than a value MaxSOCZone3 corresponding to a predetermined voltage VminZone4 is, on average, at least 10 times less rapid than variation in voltage for a state of charge greater than MaxSOCZone3, and wherein the charge profile further comprises an area in which variation of voltage of said cell as a function of state of charge for a state of charge less than value MinSOCZone2 corresponding to voltage VmaxZone1 is on average at least twice as rapid as variation in voltage for a state of charge between values of MinSOCZone2 and MaxSOCZone3, and wherein said charge profile for a state of charge between MinSOCZone2 and MaxSOCZone3 exhibits: said method comprising the steps of: a) providing a cell; connecting said cell to a device for charging or discharging it and measuring a current I through the cell; providing a calibration relationship between state of charge of the cell and voltage; b) providing an initial state of charge SOC(t c) measuring cell voltage V(t i) if a current I(t ii) otherwise a value SOCC(t wherein step c) further comprises determining an adjusted state of charge SOC(t i) if a current I(t ii) otherwise a value SOCC(t wherein step c) further comprises assigning a value SOC(t i) if the cell is being traversed by a current I(t