Abstract: A method for assessing a state of health of a battery having a plurality of heterogeneous cells includes subjecting the cells of the battery to a plurality of diagnostic current pulse cycles; identifying extreme cells based upon the cycles; estimating model parameters of the extreme cells; and estimating upper and lower bounds for the estimated model parameters. Estimating model parameters includes performing a recursive least squares analysis on the extreme cells. Estimating the upper and lower bounds for the estimated model parameters includes performing a sparse Gaussian process regression using the estimated model parameters.

Abstract: A method of predicting state of power (SOP) for a battery includes estimating first state parameter bounds of the battery using an internal observer process; obtaining a current value based upon the first state parameter bounds, system constraint variables, a scaling factor and a reference current using a modified reference governor process; performing adaptive parameter bounding to obtain second state parameter bounds using the current value; determining a constraint variable based upon the second state parameter bounds and whether the constraint variable is within the system constraint variables the using an interval prediction process; and generating a modified scaling factor based upon whether the constraint variable is within the system constraint variables. Using the modified scaling factor, the obtaining, performing, determining and modifying are repeated to generate a final current value. The SOP is estimated based upon the final current value.

Abstract: An interval observer based on an equivalent circuit-thermal model for lithium-ion batteries is presented. State of charge-temperature-dependent parameters are considered as unknown but bounded uncertainties in a single cell model. A parallel and a series arrangement of five cells are used for observer design, where cell heterogeneity is accounted for through the uncertainty bounding functions.

Abstract: An interval observer based on an equivalent circuit-thermal model for lithium-ion batteries is presented. State of charge-temperature-dependent parameters are considered as unknown but bounded uncertainties in a single cell model. A parallel and a series arrangement of five cells are used for observer design, where cell heterogeneity is accounted for through the uncertainty bounding functions.

Abstract: The invention relates to a method and a system for managing the charging of a rechargeable battery by a voltage control or by a current control comprising a plurality (n) of branches connected in series, each branch comprising a plurality (p) of electrochemical elements connected in parallel. Each electrochemical element exhibits a charging profile (PC) comprising at least one plateau zone directly followed by a sloping zone in which the variation of the voltage as a function of the state of charge in the plateau zone is on average at least ten times less fast than the variation of the voltage in the sloping zone.

Abstract: The invention relates to a method and a system for managing the charging of a rechargeable battery by a voltage control or by a current control comprising a plurality (n) of branches connected in series, each branch comprising a plurality (p) of electrochemical elements connected in parallel. Each electrochemical element exhibits a charging profile (PC) comprising at least one plateau zone directly followed by a sloping zone in which the variation of the voltage as a function of the state of charge in the plateau zone is on average at least ten times less fast than the variation of the voltage in the sloping zone.

Abstract: A method and system are provided for estimating state of charge of a cell having a positive electrode, for example of a lithium phosphate type, the charge profile of which includes a range of state of charge between about 30 and about 90% in which variation of voltage is 10 times less rapid than for a state of charge higher than 90%. Determination of state of charge for a state of charge greater than 90% is based on either the use of a calibration relationship between cell voltage and state of charge when a current is passing through the cell that is less than a predetermined threshold value and its voltage has stabilized, or on the use of coulometry the result of which is corrected taking into account the accuracy of the current sensor.

Abstract: The invention is a monitoring system for a battery having a plurality of accumulators. The system comprises apparatus for measuring the voltage on the terminals of each accumulator; measuring the temperature of the battery; measuring the current flowing through the battery, calculating a voltage difference between a maximum voltage measured on the terminals of one of the accumulators and a minimum voltage measured on the terminals of one of the accumulators; comparing the voltage difference with at least one threshold value depending on the measured temperature and current, and reporting an error if the voltage difference is greater than or equal to the at least one threshold value.

Abstract: A method and system are provided for estimating state of charge of a cell having a positive electrode, for example of a lithium phosphate type, the charge profile of which includes a range of state of charge between about 30 and about 90% in which variation of voltage is 10 times less rapid than for a state of charge higher than 90%. Determination of state of charge for a state of charge greater than 90% is based on either the use of a calibration relationship between cell voltage and state of charge when a current is passing through the cell that is less than a predetermined threshold value and its voltage has stabilized, or on the use of coulometry the result of which is corrected taking into account the accuracy of the current sensor.

Abstract: An electronic system for a battery designed to supply electrical power to an application, such as in an aircraft, that includes a main power supply, comprises a charging circuit (30) with a charger (K3C), a first battery discharging circuit (20) in parallel with the charging circuit, a component ensuring continuity of discharge (D3) and an electronic control unit adapted to control opening and closing of the discharge switch (K2) and adapted to control said charger (K3C). The control unit keeps the battery charged as long as it is not being called on to discharge and interrupts battery charging and sets the discharge switch (K2) to the closed position when a call for power is detected from the application, the component ensuring continuity of discharge (D3) allowing passage of a discharge current during a transitional phase of closing of the discharge switch (K2).

Abstract: The invention is a monitoring system for a battery having a plurality of accumulators. The system comprises means for measuring the voltage on the terminals of each accumulator, means for measuring the temperature of the battery, means for measuring the current flowing through the battery, means for calculating a voltage difference between a maximum voltage measured on the terminals of one of the accumulators and a minimum voltage measured on the terminals of one of the accumulators, means for comparing the voltage difference with at least one threshold value depending on the measured temperature and current, and means reporting an error if the voltage difference is greater than or equal to said at least one threshold value.

Abstract: A method to manage charge and/or discharge of a rechargeable battery comprising at least one electrochemical cell having predetermined maximum continuous charge current (IMR_C) and/or discharge current (IMD_C) allowed, the method comprising the steps of: measuring an instantaneous charge current (I); defining an overcharge capacity (Cap); determining an instantaneous maximum current allowed in charge (IMR) as a function of the overcharge capacity; and/or defining an over thermal capacity (CapTh); determining an instantaneous maximum pulse current allowed in discharge (IMD_max) as a function of the over thermal capacity.

Abstract: An electronic system for a battery designed to supply electrical power to an application, such as in an aircraft, that includes a main power supply, comprises a charging circuit (30) with a charger (K3C), a first battery discharging circuit (20) in parallel with the charging circuit, a component ensuring continuity of discharge (D3) and an electronic control unit adapted to control opening and closing of the discharge switch (K2) and adapted to control said charger (K3C). The control unit keeps the battery charged as long as it is not being called on to discharge and interrupts battery charging and sets the discharge switch (K2) to the closed position when a call for power is detected from the application, the component ensuring continuity of discharge (D3) allowing passage of a discharge current during a transitional phase of closing of the discharge switch (K2).

Abstract: A method to manage charge and/or discharge of a rechargeable battery comprising at least one electrochemical cell having predetermined maximum continuous charge current (IMR_C) and/or discharge current (IMD_C) allowed, the method comprising the steps of: measuring an instantaneous charge current (I); defining an overcharge capacity (Cap); determining an instantaneous maximum current allowed in charge (IMR) as a function of the overcharge capacity; and/or defining an over thermal capacity (CapTh); determining an instantaneous maximum pulse current allowed in discharge (IMD_max) as a function of the over thermal capacity.