Lg Chem, Ltd

Lg Energy Solution, Ltd.

Sun-Young Cha

Won-Tae Joe

Geun-Chang Chung

Young-Jin Kim

Provided is an apparatus and method for estimating a state of charge of a secondary battery. The apparatus includes a sensor unit configured to measure a voltage and a current of the secondary battery in a predetermined cycle, and a control unit operably coupled to the sensor unit. The control unit is configured to estimate the state of charge of the secondary battery in the predetermined cycle based on the voltage and the current measured by the sensor unit. The control unit is further configured to determine an operating state of the secondary battery as any one of a linear operating state and a non-linear operating state based on a threshold voltage and the measured voltage, and then determine first process noise indicating inaccuracy of a current integration model and second process noise indicating inaccuracy of an equivalent circuit model according to the determined operating state.

Apparatus and method for estimating state of charge of secondary battery

A battery management system for optimizing the internal resistance of a battery includes a current measuring unit that measures a charge current of the battery, a memory that stores a plurality of voltage-current characteristic profiles, and a control unit that determines a reference profile from the plurality of voltage-current characteristic profiles based on a state of charge and temperature of the battery. The reference profile includes a start point, an end point, and a plurality of intermediate points disposed between the start point and the end point. The control unit determines an internal resistance of the battery, sets one of the plurality of intermediate points as a reference point, determines a reference resistance based on the reference point and the end point, and determines an optimal resistance based on the charge current, the internal resistance, the reference resistance and a predetermined upper limit of charge current.

Battery management system and method for optimizing internal resistance of battery

Disclosed is an apparatus and method for managing a battery. The battery management apparatus according to an embodiment of the present disclosure includes a memory unit and a control unit. The memory unit is configured to store a plurality of discharge curve models including a first discharge curve model associated with a first state of charge value, and in this instance, the first discharge curve model defines a change in voltage of a battery having the first state of charge value over time under a first discharge condition. The control unit is connected to the memory unit, allowing communication with the memory unit, and is configured to call the first discharge curve model stored in the memory unit.

Apparatus and method for managing battery

Disclosed is a method and apparatus for estimating parameters of a battery equivalent circuit model. The battery equivalent circuit model includes a first and second resistors and a capacitor. The method includes reading a pulse discharge profile corresponding to a parameter estimation condition from a plurality of pre-stored pulse discharge profiles, the pulse discharge profile including a first number of terminal voltages sequentially measured from a battery having a specific SOC in a predetermined cycle while the battery is discharged with a specific constant current from an OCV corresponding to the specific SOC to a lower limit of discharge voltage at a specific temperature, extracting a second number of terminal voltages between the OCV and a threshold voltage from the first number of terminal voltages, and estimating resistance values of the first and second resistors based on the OCV, the constant current, and the second number of terminal voltages.

Method, apparatus and recording medium for estimating parameters of battery equivalent circuit model

Disclosed is a battery management apparatus and method. The battery management apparatus according to an embodiment of the present disclosure may be configured to, when the voltage of a battery being discharged is equal to or lower than a preset discharge threshold voltage, predict the time left for a lower limit of discharge voltage preset lower than the discharge threshold voltage from the current time, and maintain or adjust the output parameter of the battery based on the predicted remaining time.

Battery management apparatus and method thereof

Provided are a battery management system and method for optimizing an internal resistance of a battery. The battery management system includes: a current measurement unit configured to measure a discharging current of the battery; a memory configured to store a plurality of voltage-current characteristic profiles; and a control unit operatively connected to the current measurement unit and the memory and configured to determine a reference profile from the plurality of voltage-current characteristic profiles based on a state of charge and a temperature of the battery. The reference profile includes a start point, an end point, and a plurality of intermediate points positioned between the start point and the end point. The control unit is further configured to: determine an internal resistance of the battery based on the start point and the end point; set one of the plurality of intermediate points as a reference point; determine a reference resistance smaller than the internal resistance based on the reference point and the end point; and determine an optimum resistance larger than the internal resistance based on the discharging current, the internal resistance, the reference resistance, and a predetermined discharge upper limit current.

Disclosed is a battery management apparatus and method for calibrating the state of charge (SOC) of a lithium iron phosphate (LFP) battery. The battery management apparatus according to an embodiment of the present disclosure calculates, when going into calibration mode, an average voltage value of voltage values received from a voltage measuring unit for a predefined time, calculates an average current value of current values received from a current measuring unit for the predefined time, calculates an average internal resistance value of the LFP battery for the predefined time based on the average voltage value and the average current value, determines if the average internal resistance value is equal to or larger than a preset reference resistance value, and when the average internal resistance value is equal to or larger than the reference resistance value, calibrates the current SOC to a preset reference SOC.

Battery management apparatus and method for calibrating a state of charge of a battery

A battery management, including a voltage measuring unit electrically connected to multiple lithium iron phosphate (LFP) cells in an LFP battery, the LFP cells being connected in series, to individually measure voltage of each LFP cell and output a voltage value indicative of the measured voltage, and a control unit configured to output a first signal requesting the start of a charging process of the LFP, and when at least one of the voltage values of the multiple LFP cells outputted from the voltage measuring unit reaches a threshold voltage value while the charging process is performed by the first signal, output a second signal requesting the stop of the charging process and output a third signal requesting the start of a discharging process.

Battery management apparatus and method for protecting a lithium iron phosphate cell from over-voltage using the same

The present disclosure relates to a method and an apparatus for estimating a discharge power of a secondary battery. The method according to the present disclosure includes setting a state of charge of a secondary battery for which estimation of discharge power is intended, discharging the secondary battery with a plurality of discharge currents while measuring a discharge termination voltage corresponding to each of the discharge currents, generating a current-voltage (I-V) profile that at least forms a point of intersection with the preset discharge boundary condition, and determining a discharge power using a current value and a voltage value corresponding to the point of intersection.

Method and device for estimating discharge power of secondary battery

A resistance factor determining method of a secondary battery according to the present disclosure determines, when the secondary battery has a certain temperature and state of charge, a primary differential value regarding a charge initial I-V profile calculated from a current value at a point of intersection at which a charge final I-V profile according to changes in magnitude of the charging current meets a boundary line set to a charge upper limit as the resistance factor corresponding to the temperature and state of charge. Further, a charge power estimating apparatus and method according to the present disclosure estimates a charge power corresponding to the temperature and state of charge of the secondary battery while the secondary battery is being charged using the resistance factor pre-defined according to the state of charge and temperature of the secondary battery.

Method for determining resistance factor of secondary battery, and apparatus and method for estimating charge power using determined resistance factor

Disclosed is an apparatus for estimating a state of charge (SOC) of a secondary battery which includes (i) a cathode comprising a blended cathode material having a first cathode material and a second cathode material, wherein the first and second cathode materials have different operating voltage ranges; (ii) an anode comprising an anode material; and (iii) a separator for separating the cathode from the anode. The apparatus includes a sensor configured to measure a dynamic voltage of the secondary battery during charging of the secondary battery, and a control unit configured to identify a dynamic voltage profile of the secondary battery as a transition region voltage pattern, calculate a parameter of the transition region voltage pattern, and estimate a SOC of the secondary battery from the calculated parameter by using a predetermined relationship between the parameter and the SOC.

Apparatus and method for estimating SOC of secondary battery including blended cathode material

The present disclosure discloses a system and method of adjusting an output parameter of a secondary battery. The system according to the present disclosure determines a voltage, a current, and a temperature of the secondary battery, determines a state of charge of the secondary battery using the current, determines a deration target current value calculated from a maximum value of a predefined resistance change rate, which corresponds to the state of charge and the temperature, and an output maintaining time, when the voltage of the secondary battery decreases to a preset threshold voltage or lower, and provides an output parameter including at least one of the deration target current value and a deration target output value determined therefrom to a control system of a load device supplied with power from the secondary battery.

System for controlling output parameter of secondary battery, and method therefor

Disclosed is a battery system for a secondary battery including a blended cathode material, and an apparatus and method for managing a secondary battery having a blended cathode material. The blended cathode material includes at least a first cathode material and a second cathode material. The first and second cathode materials have different operating voltage ranges. When the secondary battery comes to an idle state or a no-load state, the battery system detects a voltage relaxation occurring by the transfer of operating ions between the first and second cathode materials.

Battery system for secondary battery comprising blended cathode material, and apparatus and method for managing the same

A method for estimating an SOC-OCV profile by degradation of a secondary battery according to an embodiment of the present disclosure includes individually obtaining an SOC-OCV profile (a first profile) of a cathode of the secondary battery and an SOC-OCV profile (a second profile) of an anode of the secondary battery using a half cell; obtaining a new SOC-OCV profile (a third profile) of the cathode by reflecting a level of degradation (a %) by use of the secondary battery to modify the SOC-OCV profile of the cathode, but setting only an SOC range to be narrow in proportion to the level of degradation while maintaining an OCV range of the cathode as it is; obtaining a new SOC-OCV profile (a fourth profile) of the anode by migrating the SOC-OCV profile of the anode in a horizontal direction taking into account the level of degradation by use of the secondary battery; and obtaining a new SOC-OCV profile (a fifth profile) by determining a subtraction of an OCV value by the SOC-OCV profile of the anode from an OCV value by the SOC-OCV profile of the cathode as an OCV value of the secondary battery.

Method for estimating SOC-OCV profile by degradation of secondary battery

Disclosed is an apparatus and method for estimating a parameter of a secondary battery. The apparatus according to the present disclosure includes a sensor means configured to measure a plurality of current-voltage data while a charging current decreases when a secondary battery is charged in such a pattern that the charging current increases to a peak value and then decreases, and a control means configured to receive an input of the plurality of current-voltage data from the sensor means, calculate a linear approximation equation representing a correlation between a current and a voltage from the plurality of current-voltage data, and estimate a Y intercept of the linear approximation equation as an open-circuit voltage of the secondary battery.

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Daejeon, South Korea

Sun-Young Cha