DEVICE AND METHOD FOR BATTERY MODULE EQUALIZATION

Description

[Technical Field]

[0001] The present invention relates to an apparatus and a method of equalizing a battery module, and more particularly, to an apparatus and a method of equalizing a battery module, which supply an equalization current to a battery module which is diagnosed to have abnormality via an equalization current supply circuit when abnormality is generated in a state of charge (SoC) of one or more battery modules, and equalize the SoC of the one or more battery modules.[Background Art]

[0002] In general, a secondary battery may be used as one battery module by joining a plurality of unit secondary battery cells in an environment requiring a high capacity, such as an electric vehicle, an energy storage system, and an uninterruptible power supply, and the plurality of battery modules may be joined and used depending on the case.

[0003] When the plurality of battery modules is used together, a voltage of the plurality of battery modules may be imbalanced due to various reasons, such as a deviation generated during the production of the battery module and a temperature deviation of the battery module.

[0004] In the meantime, when the battery modules having imbalanced voltages are joined and used, there is a problem in that available capacities and power of the plurality of battery modules are decreased and aging of the battery module is accelerated to decrease a life span of the battery module.

[0005] EP 2 339 717 relates to a secondary cell control system. WO 2009 / 051415 relates to a battery management system with integration of voltage sensor and charge equalizer. KR 101 387 658 relates to a method of balancing battery cell in battery module for energy reduction. US 2010 / 225277 relates to a battery charge and discharge controller. EP 3 086 435 relates to a battery control method and apparatus, battery module, and battery pack.

[0006] In this respect, in order to solve the problem generated when the battery modules having the imbalanced voltages are joined and used, the present inventor invented an apparatus and a method of equalizing a battery module, which supply an equalization current to a battery module which is diagnosed to have abnormality via an equalization current supply circuit when the abnormality is generated in a state of charge (SoC) of one or more battery modules and equalize the SoC of the one or more battery modules.[Detailed Description of the Invention][Technical Problem]

[0007] The present invention is conceived to solve the foregoing problems, and is to provide an apparatus and a method of equalizing a battery module, which control switching units included in cell module controllers (CMCs), respectively, based on a location of a battery module which is diagnosed to have abnormality when the abnormality is generated in a state of charge (SoC) of battery modules, form an equalization current supply circuit that is a closed circuit including a battery module controller (BMC) and the battery module which diagnosed to have the abnormality, and supply an equalization current to the battery module which is diagnosed to have the abnormality via the equalization current supply circuit, thereby equalizing the SoC of the battery modules.[Technical Solution]

[0008] The invention is claimed in claim 1. Preferred embodiments are claimed in dependent claims.

[0009] Notably, the invention provides an apparatus for equalizing a battery module according to an exemplary embodiment of the present invention includes: a plurality of cell module controllers (CMCs) which are connected with a plurality of battery modules, respectively, wherein each CMC is adapted to measure a voltage at ends of its respectively connected battery module among the battery modules; and a battery module controller (BMC) which calculates a state of charge (SoC) of each of the battery modules based on the measured voltages at ends of each of battery modules, and diagnoses abnormality of each of the battery modules based on the calculated SoC, and the BMC controls plurality of switching units included in the CMCs, respectively, based on a location of the battery module which is diagnosed to have the abnormality among the battery modules, wherein it performs the control by forming an equalization current supply circuit that is a closed circuit including the BMC and the battery module which is diagnosed to have the abnormality, and supplying an equalization current to the battery module which is diagnosed to have the abnormality via the equalization current supply circuit.

[0010] The BMC forms the equalization current supply circuit by controlling the switching unit included in the CMC connected with the battery module which is diagnosed to have the abnormality to set it in an on state and the switching unit included in the CMC connected to a front end of the CMC connected with the battery module which is diagnosed to have the abnormality.

[0011] The apparatus further includes an equalization BUS and a communication BUS which connect the CMCs and the BMC, the equalization BUS and the communication BUS connecting the one or more CMCs and the BMC by a daisy chain connection scheme.

[0012] The equalization BUS includes: a positive BUS which serially connects a plurality of CMCs located at odd-numbered places, wherein the first place is at the CMC located at the last end among the CMCs; and a negative BUS which serially connects a plurality of CMCs located at even-numbered places.

[0013] In an exemplary embodiment, when the abnormality is not diagnosed in the battery modules, the CMCs may maintain the switching units in an off state.

[0014] In an exemplary embodiment, the BMC may include an auxiliary switching unit which controls an electrical conduction state with a CMC located at the first end among the CMCs, and when it is diagnosed that a battery module located at the first end has abnormality, the BMC may form the equalization current supply circuit so as to include the battery module located at the first end by controlling electrical conduction states of the switching unit included in the CMC located at the first end and the auxiliary switching unit.

[0015] In an exemplary embodiment, each of the CMCs may further include: a connector unit which selectively connects the battery module connected to each of the CMCs, the switching unit included in each of the CMCs, and the equalization BUS; a voltage sensing unit which measures the voltage at ends of the battery module connected to each of the CMCs; a fuse unit which connects a negative electrode of the battery module connected to each of the CMCs and the switching units; a balancing unit which discharges the battery module connected to each of the CMCs; and a control unit which controls an operation of the balancing unit based on the measured voltage.

[0016] In an exemplary embodiment, the BMC may include: an equalization current supply unit which supplies the equalization current to the battery module which is diagnosed to have the abnormality; and a voltage measuring unit which measures a voltage of the equalization BUS, and positive terminals of the equalization current supply unit and the voltage measuring unit may be connected with the positive BUS, and negative terminals of the equalization current supply unit and the voltage measuring unit may be connected with the negative BUS.

[0017] In an exemplary embodiment, the BMC may form a module location identifying circuit by controlling a switching unit included in a CMC of which a location is desired to be recognized among the CMCs, and identify the location of the CMC of which the location is desired to be recognized based on a voltage applied to the module location identifying circuit.

[0018] The invention also provides a method of equalizing a battery module by the battery module equalizing apparatus described above, wherein the method includes: measuring voltages at ends of the battery modules connected to the cell module controllers (CMCs), respectively; diagnosing abnormality of each of the battery modules based on a state of charge (SoC) of each of the battery modules calculated based on the measured voltages at ends of each of the battery modules; and controlling the switching units included in the CMCs, respectively, based on a location of the battery module which is diagnosed to have the abnormality among the battery modules, and forming an equalization current supply circuit that is a closed circuit including an equalization current supply unit that supplies an equalization current and the battery module which is diagnosed to have the abnormality.

[0019] The supplying of the equalization current includes forming the equalization current supply circuit by controlling the switching unit included in each of the CMCs connected with the battery module which is diagnosed to have the abnormality to set it into the on state and the switching unit included in the CMC connected to the front end of the CMC connected with the battery module which is diagnosed to have the abnormality to set it into the on state.

[0020] In an exemplary embodiment, the method may further include when the abnormality is not diagnosed in the battery modules, maintaining the switching units in an off state.

[0021] In an exemplary embodiment, the supplying of the equalization current may include when it is diagnosed that the battery module located at the first end has abnormality, forming the equalization current supply circuit so as to include the battery module located at the first end by controlling electrical conduction states of the switching unit included in the CMC located at the first end and the auxiliary switching unit connected with the CMC located at the first end among the CMCs.

[0022] In an exemplary embodiment, the measuring of each of the voltages may include: selectively connecting the battery module connected to each of the CMCs, the switching unit included in each of the CMCs, and the equalization BUS; measuring voltages at ends of the battery module connected to each of the CMCs; connecting a negative electrode of the battery module connected to each of the CMCs and the switching units; and discharging the battery module connected to each of the CMCs.

[0023] In an exemplary embodiment, the supplying of the equalization current may include: supplying the equalization current to the battery module which is diagnosed to have the abnormality; and measuring a voltage of the equalization BUS, and positive terminals of the equalization current supply unit and the voltage measuring unit may be connected with the positive BUS, and negative terminals of the equalization current supply unit and the voltage measuring unit may be connected with the negative BUS.

[0024] In an exemplary embodiment, the supplying of the equalization current may include: forming a module location identifying circuit by controlling a switching unit included in a CMC of which a location is desired to be recognized among the CMCs; and identifying the location of the CMC of which the location is desired to be recognized based on a voltage applied to the module location identifying circuit.[Advantageous Effects]

[0025] The present invention controls switching units included in cell module controllers (CMCs), respectively, based on a location of a battery module which is diagnosed to have abnormality when the abnormality is generated in a state of charge (SoC) of the battery modules, forms an equalization current supply circuit that is a closed circuit including a battery module controller (BMC) and the battery module which diagnosed to have the abnormality, and supplies an equalization current to the battery module which is diagnosed to have the abnormality via the equalization current supply circuit, thereby having an advantage in equalizing the SoC of the battery modules.

[0026] Further, the present invention forms a module location identifying circuit by controlling a switching unit of cell module controllers (CMCs) connected with the battery modules, respectively, and identifies a location of the CMC based on a voltage applied to the module location identifying circuit, thereby having an advantage in identifying the location of the CMC without adding a separate constituent element.[Brief Description of Drawings]

[0027] FIG. 1 is a diagram schematically illustrating constituent elements of a battery module equalizing apparatus 100 according to an exemplary embodiment of the present invention. FIG. 2 is a diagram illustrating a cell module controller 110 included in the battery module equalizing apparatus 100 according to the exemplary embodiment of the present invention in more detail. FIG. 3 is a diagram schematically illustrating an equalization current supply circuit formed in the battery module equalizing apparatus 100 according to the exemplary embodiment of the present invention. FIG. 4 is a diagram schematically illustrating an equalization current supply circuit formed when abnormality of a battery module located at the first end is diagnosed in the battery module equalizing apparatus 100 according to the exemplary embodiment of the present invention. FIG. 5 is a diagram schematically illustrating a module location identifying circuit formed in the battery module equalizing apparatus 100 according to the exemplary embodiment of the present invention. FIG. 6 is a diagram schematically illustrating another form of the module location identifying circuit formed in the battery module equalizing apparatus 100 according to the exemplary embodiment of the present invention. FIG. 7 is a flowchart for describing a series of processes for equalizing battery modules 10 by using the battery module equalizing apparatus 100 according to the exemplary embodiment of the present invention. FIG. 8 is a flowchart for describing a series of processes for identifying a location of cell module controllers 110 by using the battery module equalizing apparatus 100 according to the exemplary embodiment of the present invention. [Best Mode]

[0028] Hereinafter, an exemplary embodiment is presented for helping understanding of the present invention. However, the exemplary embodiment below is simply provided for more easy understanding of the present invention, and the contents of the present invention are not limited by the exemplary embodiment.

[0029] FIG. 1 is a diagram schematically illustrating constituent elements of a battery module equalizing apparatus 100 according to an exemplary embodiment of the present invention.

[0030] Referring to FIG. 1, a battery module equalizing apparatus 100 according to an exemplary embodiment of the present invention includes a plurality of cell module controllers (CMCs) 110 and a battery module controller (BMC) 120.

[0031] First, the CMCs 110 are connected to a plurality of battery modules 10, respectively. each among the CMCs 110 measures a voltage at ends of its respective connected battery module among the battery modules 10, respectively. Hereinafter, the CMCs 110 will be described in more detail with reference to FIG. 2.

[0032] FIG. 2 is a diagram illustrating the cell module controller 110 included in the battery module equalizing apparatus 100 according to the exemplary embodiment of the present invention in more detail.

[0033] Referring to FIG. 2, each of the CMCs 110 includes a switching unit 112, and may further include a connector unit 111, a voltage sensing unit 113, a balancing unit 114, a control unit 115, and a fuse unit 116.

[0034] The connector unit 111 may internally connect a positive terminal of the battery module 10 connected to each of the CMCs 110 and the switching unit 112 included in each of the CMCs 110. Further, the connector unit 111 may externally selectively connect one or more of the positive terminal of the battery module 10 connected to each of the CMCs 110 and the switching unit 112 included in each of the CMCs 110 and an equalization BUS which is to be described below. To this end, the connector unit 111 may be formed by one or more connectors.

[0035] The switching unit 112 may control an electrical conduction state between the connector unit 111 and a negative terminal of the batter module 10 connected to each CMC 110. For example, the switching unit 112 may be a switching device, such as a relay, a contactor, a transistor, and a thyristor, and may control an electrical conduction state between the negative terminals of the battery modules 10 connected to the CMCs 110, respectively, according to the electrical conduction state of the switching device. Further, the switching unit 112 may be confirmed by one or more switching devices as necessary.

[0036] In the exemplary embodiment, the switching unit 112 included in each of the CMCs 110 may be maintained in an off state when abnormality of the battery module 10 is not diagnosed by the BMC 120 which is to be described below.

[0037] The voltage sensing unit 113 may sense voltage values at both ends of the battery module 10 connected to each CMC 110. For example, the voltage sensing unit 113 may be a shunt resistor, and transmit a voltage value applied to the shunt resistor to a control unit 115 which is to be described below. However, the present invention is not limited thereto.

[0038] In the exemplary embodiment, the voltage sensing unit 113 may provide the sensed voltage values at both ends of the battery module 10 to the BMC which is to be described below.

[0039] The balancing unit 114 may additionally consume power of the connected battery module 10 based on the voltage value of the connected battery module 10. For example, the balancing unit may include one or more switches (not illustrated) and one or more resistors (not illustrated). The balancing unit 114 may receive a balancing unit control signal from the control unit 115 which is to be described below and consume power of the battery module 10 in the form of heat by using the one or more resistors.

[0040] The control unit 115 may output a switching unit control signal to the switching unit 112. Herein, the switching unit control signal may be a control signal that is capable of changing an electrical conduction state of the switching unit 112.

[0041] In the exemplary embodiment, each of the CMCs 110 may further include a switch driving unit (not illustrated) driving a switch, and when the switching unit control signal is output from the control unit 115, the switch driving unit controls the switching unit 112, thereby changing an electrical conduction state of the switching unit 112. Further, the control unit 115 may output the balancing unit control signal to the balancing unit 114. Herein, the balancing unit control signal may be a signal controlling an electrical conduction state of a switch included in the balancing unit 114. The control unit 115 changes a state of the switch to an on-state based on the voltage value of the battery module 10 sensed in the voltage sensing unit 113, and consumes power by using the resistor included in the balancing unit 114, thereby enabling the balancing unit 114 to operate.

[0042] In the exemplary embodiment, the control unit 115 is one integrated circuit and may include a micro controller unit (MCU) which is capable of controlling a plurality of constituent elements.

[0043] The fuse unit 116 may be connected between the negative terminal of the connected battery module 10 and the switching unit 112. In the exemplary embodiment, the fuse unit 116 may include an overcurrent blocking fuse (not illustrated) and a temperature fuse (not illustrated). The overcurrent blocking fuse may operate when an overcurrent flows between the battery module 10 and the switching unit 112 and block the overcurrent of the battery module 10. The temperature fuse may be located to be adjacent to the balancing unit, and the temperature fuse operates when a temperature generated in the balancing unit is equal to or higher than a reference temperature, thereby preventing the battery module 10 and the CMC 110 from being damaged due to an over-temperature.

[0044] In the exemplary embodiment, each of the CMCs 110 may further include a power unit (not illustrated). The power unit may reduce a voltage of the battery module 10 and provide the reduced voltage so as for the constituent elements included in CMCs 110 to operate. For example, when the control unit 115 is an MCU, the power unit may reduce a voltage to 3 to 5 V that is a permitted voltage of the MCU and provide the reduced voltage to the control unit 115.

[0045] Referring back to FIG. 1, the CMCs 110 are connected by a daisy chain connection scheme. To this end, the battery module equalizing apparatus 100 according to the exemplary embodiment of the present invention includes a communication BUS and the equalization BUS.

[0046] The communication BUS connects the CMCs 110 by the daisy chain connection scheme. The communication BUS may connect each CMC 110 and the BMC 120 which is to be described below, and enable each CMC 110 and the BMC 120 to transceive data.

[0047] The equalization BUS connects the CMCs 110 by the daisy chain connection scheme. To this end, the equalization BUS is configured by a positive BUS and a negative BUS.

[0048] The positive BUS may be a BUS connected from the positive terminal of the battery module 10 located at the first end. The positive BUS serially connects the CMCs 110 located at the odd-numbered places based on the CMC 110 located at the last end among the CMCs 110. For example, when N CMCs 110 are connected to N battery modules 10, respectively (N is an even number), a number of each CMC may be sequentially set from the CMC 110 located at the last to the CMC 110 located at the first end. In this case, the CMC 110 located at the last may be set by number 1, and the positive BUS may connect the first CMC 110, the third CMC 110, the fifth CMC 110, ..., and the N-1 th< CMC 110.

[0049] The negative BUS may be a BUS connected from the negative terminal of the battery module 10 located at the last. The negative BUS serially connects the CMCs 110 located at the even-numbered places based on the CMC 110 located at the last among the CMCs 110. For example, when the CMC 110 located at the last is set by number 1, the negative BUS may connect the second CMC 110, the fourth CMC 110, the sixth CMC 110, ..., and the N th< CMC 110.

[0050] The BMC 120 calculates a state of charge (SoC) of the battery modules based on the voltages at ends of the battery modules 10 measured from the CMCs 110, and diagnoses abnormality of each of the battery modules 10 based on the calculated SoC. For example, the BMC 120 may measure a voltage of the battery modules 10, and compare the measured voltage with a discharge curve of the corresponding battery module 10 and calculate an SoC. The BMC 120 may compare the calculated SoC with a reference SoC value, select the battery module 10 of which the calculated SoC is equal to or smaller than the reference SoC value, and diagnose that the selected battery module 10 has abnormality. Herein, the reference SoC value may mean a minimum SoC value calculated when the battery module 10 is a normal state, and may be set by various values according to the kind of battery module 10 and a demand of a user.

[0051] In the exemplary embodiment, the BMC 120 controls the switching units included in the CMCs 110, respectively, based on a location of the battery module which is diagnosed to have the abnormality among the battery modules 10, thereby forming an equalization current supply circuit that is a closed circuit including the BMC 120 and the battery module 10 which is diagnosed to have the abnormality. Further, the BMC 120 may supply an equalization current to the battery module 10 which is diagnosed to have the abnormality via the formed equalization current supply circuit. Hereinafter, a series of processes of forming the equalization current supply circuit and supplying an equalization current to the battery module 10 having the abnormality via the formed equalization current supply circuit by the BMC 120 will be described with reference to FIGS. 3 and 4.

[0052] FIG. 3 is a diagram schematically illustrating the equalization current supply circuit formed in the battery module equalizing apparatus 100 according to the exemplary embodiment of the present invention.

[0053] Referring to FIG. 3, the BMC 120 may supply an equalization current to the battery module 10 which is diagnosed to have abnormality via the equalization current supply circuit. To this end, the BMC 120 may include an equalization current supply unit 121.

[0054] The equalization current supply unit 121 may receive a voltage from battery modules 10, convert the received voltage to a voltage having a predetermined size, and transmit the received voltage to the battery module 10 having the abnormality. For example, the equalization current supply unit 121 may be an isolated converter, such as a DC-DC converter. However, the present invention is not limited thereto.

[0055] The BMC 120 forms the equalization current supply circuit by controlling the switching unit 112 included in each of the CMCs 110 connected with the battery module 10 which is diagnosed to have the abnormality and the CMC 110 connected to a front end of the CMC 110 connected with the battery module 10 which is diagnosed to have the abnormality. For example, when the battery module 10-1 located at the last end and the CMC 110-1 are set by number 1 and abnormality is generated in the SoC of the battery module 10-2 of number 2, the BMC 120 may output a control signal to the CMC 110-2 of number 2 and the CMC 110-3 of number 3. Herein, the control signal may be a signal controlling the control unit 115 included in CMCs 110 to output the switching control signal. In another exemplary embodiment, the control signal may be a signal directly controlling, by the BMC 120, an electrical conduction state of the switching unit 112 included in the CMCs 110. The CMC 110-2 of number 2 and the CMC 110-3 of number 3 may receive the control signal from the BMC 120, and control the conduction states of the switching units 112-2 and 112-3 included in the CMC 110-2 of number 2 and the CMC 110-3 of number 3, respectively, to be in an on-state. Accordingly, the BMC 120 may form the equalization current supply circuit illustrated in FIG. 3, and the equalization current may be provided to the battery module 10-2 having the abnormality. That is, the equalization current supply circuit may be formed with the connector unit 111-1 of number 1, the connector of number 3 111-3, the switching unit 112-3 of number 3, the negative terminal of the battery module 10-3 of number 3, the battery module 10-2 having the abnormality, the switching unit 112-2 of number 2, the connector unit 111-2 of number 2, and the equalization current supply unit 121. The equalization current supply unit 121 may provide the battery module 10-2 having the abnormality with the equalization current via the equalization current supply circuit formed as described above.

[0056] In the meantime, when abnormality is generated in the battery module 10 located at the first end, the CMC 110 is not located at the front end of the CMC 110 located at the first end, so that it may be difficult to form the equalization current supply circuit by the same method as the foregoing method. In order to supplement the difficulty, the BMC 120 may include an auxiliary switching unit 122, and when abnormality is generated in the battery module 10 located at the first end, the equalization current supply circuit may be formed by controlling electrical conduction states of the auxiliary switching unit 122 and the switching unit 112 included in the CMC 110 located at the first end. Hereinafter, this will be described in more detail with reference to FIG. 4.

[0057] FIG. 4 is a diagram schematically illustrating the equalization current supply circuit formed when abnormality of a battery module located at the first end is diagnosed in the battery module equalizing apparatus 100 according to the exemplary embodiment of the present invention.

[0058] Referring to FIG. 4, when the battery module 10-n located at the first end has abnormality, the BMC 120 may output a control signal to the CMC 110-n located at the first end and the auxiliary switching unit 122. The switching unit 112-n included in the CMC 110-n located at the first end and the auxiliary switching unit 122 may receive the control signal, and the states of the switching unit 112-n and the auxiliary switching unit 122 may be controlled to an on-state based on the control signal. Accordingly, the equalization current supply circuit illustrated in FIG. 4 is formed, thereby providing an equalization current to the battery module 10-n that has the abnormality and is located at the first end. That is, the equalization current supply circuit may form the equalization current supply circuit including the auxiliary switching unit 122, the connector unit 111-n of the CMC 110-n located at the first end, the battery module 10-n located at the first end, the switching unit 112-n of the CMC 110-n located at the first end, the connector unit 111-n of the CMC 110-n located at the first end, and the connector unit 111-n-2 of the even-numbered CMC 110-n-2 based on the last end. The equalization current supply unit 121 may provide the battery module 10-n located at the first end with the equalization current via the equalization current supply circuit formed as described above.

[0059] In the exemplary embodiment, the BMC 120 may further include an equalization circuit switching unit 124 which is located at an output terminal of the equalization current supply unit 121 and changes an electrical conduction state of the output terminal of the equalization current supply unit 121.f

[0060] The equalization current switching unit 124 may control the electrical conduction state of the output terminal of the equalization current supply unit 121 in order to form the equalization current supply circuit for supplying the equalization current to the battery module which is diagnosed to have the abnormality. For example, the equalization circuit switching unit 124 may be four single pole single throw (SPST) switches as illustrated in FIGS. 1, and 3 to 6. However, the present invention is not limited thereto, any constituent element which is capable of blocking an output voltage of the output terminal of the equalization current supply unit 121 may be applied.

[0061] In the exemplary embodiment, the BMC 120 may form a module location identifying circuit by controlling the switching unit 112 included in the CMC 110 of which a location is desired to be recognized among the CMCs 110. Further, the BMC may identify a location of the CMC 110 of which a location is desired to be recognized based on a voltage applied to the module location identifying circuit. Hereinafter, this will be described in more detail with reference to FIGS. 5 and 6.

[0062] FIG. 5 is a diagram schematically illustrating a module location identifying circuit formed in the battery module equalizing apparatus 100 according to the exemplary embodiment of the present invention, and FIG. 6 is a diagram schematically illustrating another form of the module location identifying circuit formed in the battery module equalizing apparatus 100 according to the exemplary embodiment of the present invention.

[0063] Referring to FIGS. 5 and 6, the BMC 120 may form the module location identifying circuit by controlling the switching unit 112 of the CMC 110 of which a location is desired to be recognized, and identify a location of the corresponding CMC 110 based on a voltage of the formed module location identifying circuit. To this end, the BMC 120 may include a voltage measuring unit 123.

[0064] A positive terminal of the voltage measuring unit 123 is connected with the positive BUS and a negative terminal of the voltage measuring unit 123 is connected with the negative BUS, thereby measuring a voltage applied to the module location identifying circuit. For example, when it desires to recognize a location of the CMC 110 located at the front end of the CMC 110 located at the last end, the BMC 120 may control an electrical conduction state of the switching unit 112 included in the CMC 110 of which a location is desired to be recognized, that is, the CMC 110 located at the front end of the CMC 110 located at the last end. Accordingly, the module location identifying circuit illustrated in FIG. 5 may be formed, and the module location identifying circuit may include only one battery module among N battery modules 10. Accordingly, the voltage applied to the module location identifying circuit measured via the voltage measuring unit 123 may be the voltage of one battery module. Further, when it desires to recognize a location of the third-placed CMC 110 based on the CMC 110 located at the last end, the BMC 120 may control an electrical conduction state of the switching unit 112 included in the third-placed CMC 110. Accordingly, the module location identifying circuit illustrated in FIG. 6 may be formed, and the module location identifying circuit may include N-2 battery modules among N battery modules 10. Accordingly, the voltage applied to the module location identifying circuit measured via the voltage measuring unit 123 may be the voltages of N-2 battery modules. That is, when the foregoing method is applied to the case where 10 battery modules 10 having a voltage of 1 V are joined and used, the voltages of 0 V to 9 V may be measured according to the locations of 10 CMCs 110. The BMC 120 may pre-store a voltage value according to the locations of the CMCs 110, and may match the voltage measured via the voltage measuring unit 123 among the prestored voltage values with a corresponding voltage value and identify a location of the CMC 110 of which a location is desired to be recognized.

[0065] In another exemplary embodiment, the BMC 120 may form the module location identifying circuit for each of the CMCs 110 and measure a voltage via the voltage measuring unit 123, and assign an identification number to each of the CMCs 110 based on a size of the measured voltage.

[0066] Hereinafter, a method of equalizing the battery modules 10 by using the battery module equalizing apparatus 100 according to the exemplary embodiment of the present invention will be described with reference to FIGS. 7 and 8.

[0067] FIG. 7 is a flowchart for describing a series of processes for equalizing the battery modules 10 by using the battery module equalizing apparatus 100 according to an exemplary embodiment of the present invention.

[0068] First, voltages of both ends of the battery modules connected with the CMCs are measured (S110). The BMC may receive the voltages of both ends of the battery module measured in operation S110 and calculate an SoC of each of the battery modules (S120). The BMC diagnoses abnormality of the SoC of each of the battery modules based on the calculated SoC of the battery modules (S130). When the battery modules has abnormality as a result of the diagnosis of the battery modules in operation S130, the states of the switching units included in the CMC connected with the battery module which is diagnosed to have the abnormality and the CMC connected to the front end of the corresponding CMC are controlled to an on-state to form an equalization current supply circuit (S140). The equalization current supply unit supplies an equalization current to the battery module having the abnormality via the equalization current supply circuit formed in operation S140 (S150). The equalization current is supplied in operation S150, so that when the SoC of the battery modules is equalized and has no abnormality, the BMC controls the states of the switching units included in the CMC connected with the battery module which is diagnosed to have the abnormality and the CMC connected to the front end of the corresponding CMC to an off state and performs a normal operation S160. When it is determined that the battery module having the abnormality still has abnormality even after operation S150 is performed, the SoC of the battery modules may be equalized by repeatedly performing operation S150.

[0069] FIG. 8 is a flowchart for describing a series of processes for identifying a location of cell module controllers 110 by using the battery module equalizing apparatus 100 according to the exemplary embodiment of the present invention.

[0070] First, the BMC controls a state of a switching unit included in a CMC of which a location is desired to be recognized to an on-state and forms a module location identifying circuit (S210). The BMC measures a voltage applied to the module location identifying circuit formed in operation S210 via the voltage measuring unit (S220). Then, the BMC matches a CMC corresponding to the voltage measured via the voltage measuring unit among the CMCs (S230). The BMC recognizes a location of the CMC of which the location is desired to be recognized based on the CMC matched in operation S230.

[0071] The method of equalizing the battery modules 10 and the method of recognizing the location of the CMC by using the battery module equalizing apparatus 100 have been described with reference to the flowcharts presented in the drawings. For a simplified description, the method is illustrated and described with the series of blocks, but the present invention is not limited to the order of the blocks, and some blocks may be occurred in the different order from the order illustrated and described in the present specification or may be occurred with other blocks at the same time, and various other branches, a flow path, and orders of the blocks achieving the same or similar result may be implemented. Further, for the implementation of the method described in the present specification, all of the illustrated blocks may not be required.

Claims

1. An apparatus for equalizing a battery module (10-1, ..., 10-n), the apparatus comprising: a plurality (110) of cell module controllers, CMCs (110-1, ..., 110-n), which are connected with a plurality (10) of battery modules (10-1, ..., 10-n), respectively, wherein each CMC (110-1, ..., 110-n) is adapted to measure a voltage at ends of its respective connected battery module (10-1, ..., 10-n) among the plurality (10) of battery modules (10-1, ..., 10-n); and a battery module controller, BMC (120), which is adapted to calculate a state of charge, SoC, of each of the plurality (10) of battery modules (10-1, ..., 10-n) based on the measured voltages at ends of each of the battery modules (10-1, ..., 10-n), wherein the BMC (120) is adapted to diagnose abnormality of each of the plurality (10) of battery modules (10-1, ..., 10-n) based on the calculated SoC, wherein the BMC (120) is adapted to control a plurality of switching units (112-1, ... , 112-n) included in the plurality (110) of the CMCs (110-1, ..., 110-n), respectively, based on a location of the battery module (10-2) which is diagnosed to have the abnormality among the plurality (10) of battery modules (10-1, ..., 10-n), wherein the BMC (120) is adapted to perform said control by forming an equalization current supply circuit that is a closed circuit including the BMC (120) and the battery module (10-2) which is diagnosed to have the abnormality, and supplying an equalization current to the battery module (10-2) which is diagnosed to have the abnormality via the equalization current supply circuit, wherein the apparatus comprises: an equalization BUS and a communication BUS which connect the plurality (110) of the CMCs (110-1, ..., 110-n) and the BMC (120) by a daisy chain connection scheme, wherein the equalization BUS includes: a positive BUS which serially connects a plurality of the CMCs (110-1, 110-3) located at odd-numbered places, wherein the first place is at the CMC (110-1) located at the last end among the plurality (110) of the CMCs (110-1, ..., 110-n); and a negative BUS which serially connects a plurality of the CMCs (110-2) located at even-numbered places, wherein the BMC (120) is configured to form the equalization current supply circuit by controlling the switching unit (112-2) included in the CMC (110-2) connected with the battery module (10-2) which is diagnosed to have the abnormality to set it in an on state and the switching unit (112-3) included in the CMC (110-3) connected to a front end of the CMC (110-2) connected with the battery module (10-2) which is diagnosed to have the abnormality to set it in the on state.

2. The apparatus of claim 1, wherein when the abnormality is not diagnosed in the plurality (10) of the battery modules (10-1, ..., 10-n), the plurality (110) of the CMCs (110-1, ..., 110-n) are configured to maintain the plurality of switching units (112-1, ... , 112-n) in an off state.

3. The apparatus of claim 1, wherein the BMC (120) includes an auxiliary switching unit (122) which is adapted to control an electrical conduction state with a CMC (110-n) located at the first end among the plurality (110) of the CMCs (110-1, ..., 110-n), and when it is diagnosed that a battery module (10-n) located at the first end has abnormality, the BMC (120) is adapted to form the equalization current supply circuit so as to include the battery module (10-n) located at the first end by controlling electrical conduction states of the switching unit (112-n) included in the CMC located at the first end and the auxiliary switching unit (122).

4. The apparatus of claim 1, wherein each of the plurality (10) of the CMCs (110-1, ..., 110-n) further includes: a connector unit (111-1, ..., 111-n) which is adapted to selectively connect the battery module (10-1, ..., 10-n) connected to each of the CMCs (110-1, ..., 110-n), the switching unit (112-1, ..., 112-n) included in each of the CMCs (110-1, ..., 110-n), and the equalization BUS; a voltage sensing unit (113) which is adapted to measure the voltage at ends of the battery module (10-1, ..., 10-n) connected to each of the CMCs (110-1, ..., 110-n); a fuse unit (116) which connects a negative electrode of the battery module (10-1, ..., 10-n) connected to each of the CMCs (110-1, ..., 110-n) and the one or more switching units (112-1, ..., 112-n); a balancing unit (114) which is adapted to discharge the battery module (10-1, ..., 10-n) connected to each of the CMCs (110-1, ..., 110-n); and a control unit (115) which is adapted to control an operation of the balancing unit (114) based on the measured voltage.

5. The apparatus of claim 1, wherein the BMC (120) includes: an equalization current supply unit (121) which is adapted to supply the equalization current to the battery module(10-2) which is diagnosed to have the abnormality; and a voltage measuring unit (123) which is adapted to measure a voltage of the equalization BUS, and positive terminals of the equalization current supply unit (121) and the voltage measuring unit (123) are connected with the positive BUS, and negative terminals of the equalization current supply unit (121) and the voltage measuring unit (123) are connected with the negative BUS.

6. The apparatus of claim 1, wherein the BMC (120) is adapted to form a module location identifying circuit by controlling a switching unit (112-1, ..., 112-n) included in a CMC (110-1, ..., 110-n) of which a location is desired to be recognized among the one or more CMCs (110-1, ..., 110-n), and adapted to identify the location of the CMC of which the location is desired to be recognized based on a voltage applied to the module location identifying circuit.

7. A method of equalizing a battery module by the battery module equalizing apparatus of any one of claims 1 to 6, the method comprising: measuring voltages at ends of the plurality of battery modules (10-1, ..., 10-n) connected to the plurality of the CMCs (110-1, ..., 110-n), respectively; diagnosing abnormality of each of the plurality (10) of the battery modules (10-1, ..., 10-n) based on the SoCs of each of the plurality (10) of the battery modules (10-1, ..., 10-n) calculated based on the measured voltages at ends of each of the plurality (10) of the battery modules (10-1, ..., 10-n); and controlling the plurality of switching units (112-1, ..., 112-n) included in the plurality of the CMCs (110-1, ..., 110-n), respectively, based on the location of the battery module (10-2) which is diagnosed to have the abnormality among the plurality (10) of the battery modules (10-1, ..., 10-n), and forming an equalization current supply circuit that is a closed circuit including an equalization current supply unit (121) that supplies an equalization current and the battery module (10-2) which is diagnosed to have the abnormality, wherein the supplying of the equalization current includes forming the equalization current supply circuit by controlling the switching unit (112-2) included in the CMCs (110-2) connected with the battery module (10-2) which is diagnosed to have the abnormality to set it into the on state and the switching unit (112-3) included in the CMC (110-3) connected to the front end of the CMC (110-2) connected with the battery module (10-2) which is diagnosed to have the abnormality to set it into the on state.

8. The method of claim 7, further comprising: when the abnormality is not diagnosed in the plurality of the battery modules (10-1, ..., 10-n), maintaining the plurality of switching units (112-1, ..., 112-n) in the off state.

9. The method of claim 7, for the battery module equalizing apparatus of claim 3, wherein the supplying of the equalization current includes when it is diagnosed that the battery module (10-n) located at the first end has abnormality, forming the equalization current supply circuit so as to include the battery module (10-n) located at the first end by controlling electrical conduction states of the switching unit (112-n) included in the CMC (110-n) located at the first end and the auxiliary switching unit (122) connected with the CMC (110-n) located at the first end among the plurality of the CMCs (110-1, ..., 110-n).