Calibration apparatus and calibration method for charging / discharging device

Abstract

Provided are a calibration apparatus and a calibration method for a charging / discharging device. The charging / discharging device calibration method according to the present invention comprises the steps of: obtaining, from a reference charging / discharging device, reference measurement information which is a measurement result for charging / discharging information of a first battery while a charging / discharging test for the first battery is performed by the reference charging / discharging device; obtaining, from a target charging / discharging device, target measurement information which is a measurement result for charging / discharging information of a second battery while the charging / discharging test for the second battery is performed by the target charging / discharging device; and generating calibration information for the target charging / discharging device by comparing the reference measurement information and the target measurement information.

Description

Calibration device and calibration method for a charger / discharger

[0001] The present invention relates to a technique for correcting the measurement results of a charger / discharger that performs charging / discharging of a battery.

[0002] This application claims priority to Korean Patent Application No. 10-2024-0022348, filed on February 16, 2024, and all contents disclosed in the specification and drawings of the said application are incorporated by reference into this application.

[0003] Recently, as the demand for portable electronic products such as laptops, video cameras, and mobile phones has rapidly increased, and the development of electric vehicles, energy storage batteries, robots, and satellites has been in full swing, research into high-performance batteries capable of repeated charging and discharging is actively being conducted.

[0004] Currently commercialized batteries include nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium batteries. Among these, lithium batteries are receiving attention for their advantages of being able to charge and discharge freely, having a very low self-discharge rate, and having a high energy density, as they have almost no memory effect compared to nickel-based batteries.

[0005] Currently, various types of chargers and dischargers are widely used for verifying battery charge and discharge characteristics and / or for battery activation processes in battery manufacturing plants. For a charger and discharger to perform its intended function with high accuracy, it must possess superior charge and discharge performance as well as measurement performance. Here, charge and discharge performance refers to the degree to which the charger and discharger can accurately supply the battery with the charge and discharge current or voltage indicated by user operations, while measurement performance refers to the degree to which the battery parameters during charge and discharge can be accurately measured.

[0006] High-performance chargers and dischargers are naturally more expensive and require more maintenance and upkeep than those with lower performance. Therefore, except for a few specialized applications that require extremely accurate measurements, chargers and dischargers with lower performance are limited in their use. Furthermore, as chargers and dischargers age, their measurement performance may gradually deteriorate.

[0007] The present invention has been devised to solve the above-described problems, and its purpose is to provide a device and method for correcting the measurement results of a low-precision charger / discharger (a 'target charger / discharger' to be described later) having lower measurement performance than a high-precision charger / discharger (a 'reference charger / discharger' to be described later).

[0008] Other objects and advantages of the present invention can be understood through the following description and will be more clearly understood through the embodiments of the present invention. Furthermore, it will be readily apparent that the objects and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims.

[0009] A calibration method for a charger / discharger according to one aspect of the present invention includes the steps of: obtaining reference measurement information, which is a measurement result for charge / discharge information of a first battery during a charge / discharge test performed on the first battery by the reference charger / discharger, from the reference charger / discharger; obtaining target measurement information, which is a measurement result for charge / discharge information of a second battery during a charge / discharge test performed on the second battery by the target charger / discharger, from the target charger / discharger; and generating calibration information for the target charger / discharger by comparing the reference measurement information with the target measurement information.

[0010] The above-mentioned reference measurement information may include first charge capacity information of the first battery according to the charging procedure of the charge / discharge test. The above-mentioned target measurement information may include second charge capacity information of the second battery according to the charging procedure of the charge / discharge test.

[0011] The step of generating correction information for the target charger may include a step of comparing the first charging capacity information and the second charging capacity information to determine a charging capacity correction value included in the correction information.

[0012] The above-mentioned reference measurement information may include first discharge capacity information of the first battery obtained through the discharge procedure of the charge / discharge test. The above-mentioned target measurement information may include second discharge capacity information of the second battery obtained through the discharge procedure of the charge / discharge test.

[0013] The step of generating correction information for the target charger / discharger may include a step of comparing the first discharge capacity information and the second discharge capacity information to determine a discharge capacity correction value included in the correction information.

[0014] The above-mentioned reference measurement information may include first charge / discharge efficiency information indicating a ratio between first charge capacity information of the first battery by the charge procedure of the charge / discharge test and first discharge capacity information of the first battery by the discharge procedure of the charge / discharge test. The above-mentioned target measurement information may include second charge / discharge efficiency information indicating a ratio between second charge capacity information of the second battery by the charge procedure of the charge / discharge test and second discharge capacity information of the second battery by the discharge procedure of the charge / discharge test.

[0015] The step of generating correction information for the target charger / discharger may include a step of comparing the first charge / discharge efficiency information and the second charge / discharge efficiency information to determine a charge / discharge efficiency correction value included in the correction information.

[0016] The above charger / discharger calibration method may further include a step of comparing the calibration information with previous calibration information to determine a validity condition of the calibration information.

[0017] The above charger / discharger calibration method may further include a step of generating preliminary calibration information for the target charger / discharger by comparing the calibration information with previous calibration information.

[0018] A calibration device for a charger / discharger according to another aspect of the present invention comprises: a communication unit that obtains, from a reference charger / discharger, reference measurement information, which is a measurement result for charge / discharge information of a first battery during a charge / discharge test on the first battery by the reference charger / discharger, and obtains, from a target charger / discharger, target measurement information, which is a measurement result for charge / discharge information of a second battery during a charge / discharge test on the second battery by the target charger / discharger, and a processor that compares the reference measurement information with the target measurement information to generate calibration information for the target charger / discharger.

[0019] The above-mentioned reference measurement information may include first charge / discharge efficiency information indicating a ratio between first charge capacity information of the first battery by the charge procedure of the charge / discharge test and first discharge capacity information of the first battery by the discharge procedure of the charge / discharge test. The above-mentioned target measurement information may include second charge / discharge efficiency information indicating a ratio between second charge capacity information of the second battery by the charge procedure of the charge / discharge test and second discharge capacity information of the second battery by the discharge procedure of the charge / discharge test.

[0020] The processor can compare the first charge / discharge efficiency information and the second charge / discharge efficiency information to determine a charge / discharge efficiency correction value included in the correction information.

[0021] The processor can compare the correction information with previous correction information to determine the validity condition of the correction information.

[0022] The processor can compare the calibration information with previous calibration information to generate preliminary calibration information for the target charger / discharger.

[0023] A charger / discharger calibration system according to another aspect of the present invention includes the charger / discharger calibration device.

[0024] According to at least one of the embodiments of the present invention, it is possible to determine correction information used to correct the measurement results of a low-precision charger / discharger with low measurement performance using measurement information of a high-precision charger / discharger.

[0025] Additionally, according to at least one of the embodiments of the present invention, by comparing the current calibration information with the previous calibration information, the validity condition of the current calibration information that can be used for calibration of the measurement information of the low-precision charger / discharger can be determined.

[0026] Additionally, according to at least one of the embodiments of the present invention, by comparing current correction information with previous correction information, preliminary correction information to be used from a future point in time when the validity condition of the current correction information becomes unsatisfactory can be determined in advance.

[0027] The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0028] The following drawings attached to this specification illustrate preferred embodiments of the present invention, and together with the detailed description of the invention described below, serve to further understand the technical idea of ​​the present invention, and therefore, the present invention should not be interpreted as being limited to matters described in such drawings.

[0029] FIG. 1 is a drawing exemplarily showing the configuration of a charger / discharger correction system according to one embodiment of the present invention.

[0030] Figure 2 is a drawing showing an example of the configuration of a charger.

[0031] Figure 3 is a drawing used as a reference for comparing the measurement performance of a reference charger and a target charger.

[0032] Figure 4 is a flowchart schematically illustrating a charging / discharging battery calibration method according to another embodiment of the present invention.

[0033] Figure 5 is a flowchart schematically illustrating a charging / discharging battery calibration method according to another embodiment of the present invention.

[0034] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, it should be noted that the terms and words used in this specification and claims should not be construed as limited to their conventional or dictionary meanings. Based on the principle that the inventor can appropriately define the concepts of terms to best explain his or her invention, they should be interpreted in a way that conforms to the technical spirit of the present invention.

[0035] Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, it should be understood that there may be various equivalents and modified examples that can replace them at the time of filing this application.

[0036] Terms that include ordinal numbers, such as first, second, etc., are used to distinguish one of the various components from the rest, and are not used to limit the components by such terms.

[0037] Throughout the specification, when a part is said to "include" a component, this does not exclude other components, unless otherwise stated, but rather implies that other components may be included. Furthermore, terms such as "unit" used throughout the specification mean a unit that processes at least one function or operation, and may be implemented using hardware, software, or a combination of hardware and software.

[0038] Additionally, throughout the specification, when a part is said to be "connected" to another part, this includes not only cases where it is "directly connected" but also cases where it is "indirectly connected" with other elements in between.

[0039] FIG. 1 is a drawing exemplarily showing the configuration of a charging / discharging electric correction system (1) according to one embodiment of the present invention.

[0040] Referring to Fig. 1, the charger / discharger calibration system (1) includes a reference charger / discharger (100A), a target charger / discharger (100B), and a calibration device (200).

[0041] A reference charger / discharger (100A, which may also be referred to as a “high-precision charger / discharger”) is a charger / discharger whose measurement performance has been verified in advance to be above a predetermined level. The reference charger / discharger (100A) can measure battery parameters at a first sampling rate. That is, the battery parameters can be measured by the reference charger / discharger (100A) at every first sampling period corresponding to the first sampling rate. In addition, the reference charger / discharger (100A) can measure battery parameters at a first resolution. Resolution is a term indicating the measurable precision (e.g., smallest increment) for a certain battery parameter, and the smaller the resolution, the more detailed the measurement value for the battery parameter can be obtained.

[0042] Specifically, at any timing when a battery is charged and discharged by the reference charger / discharger (100A), the difference or error rate between the measured value of the battery parameter (e.g., the charging current, the charging voltage, the discharging current and / or the discharging voltage as analog signals) measured by the reference charger / discharger (100A) and the actual value of the battery parameter may be within a predetermined allowable range (first allowable range). In addition, during a period of a predetermined length of time or longer when a battery is charged and discharged by the reference charger / discharger (100A), the average value of the difference or error rate between the measured value of the battery parameter measured by the reference charger / discharger (100A) and the actual value of the battery parameter may be within a predetermined allowable range (second allowable range).

[0043] The target charger / discharger (100B, which may also be referred to as a “low-precision charger / discharger”) is a charger / discharger whose measurement performance is below the predetermined level described above or whose measurement performance needs to be confirmed to be below the predetermined level. Specifically, unlike the reference charger / discharger (100A), at any timing when a battery is charged / discharged by the target charger / discharger (100B), the difference or error rate between the measured value of the battery parameter measured by the target charger / discharger (100B) and the actual value of the battery parameter may fall outside a predetermined allowable range (first allowable range). In addition, during a period longer than a predetermined length of time when a battery is charged / discharged by the target charger / discharger (100B), the average value of the difference or error rate between the measured value of the battery parameter measured by the reference charger / discharger (100A) and the actual value of the battery parameter may fall outside a predetermined allowable range (second allowable range).

[0044] The target charger / discharger (100B) may be designed to measure battery parameters at a second sampling rate that is lower than the first sampling rate. Accordingly, the battery parameters may be measured by the target charger / discharger (100B) at every second sampling period that is longer than the first sampling period. Accordingly, a measurement error due to a measurement gap equivalent to the time difference between the first and second sampling periods may accumulate in the measurement results of the target charger / discharger (100B). In addition, the target charger / discharger (100B) may measure battery parameters at a second resolution that is higher than the first resolution.

[0045] The correction device (200) includes a communication unit (210) and a processor (220).

[0046] The communication unit (210) is configured to support wired communication and / or wireless communication between the reference charger (100A), the target charger (100B), and the processor (220). The wired communication may be, for example, CAN (controller area network) communication, and the wireless communication may be, for example, Zigbee or Bluetooth communication. Of course, as long as it supports wired or wireless communication between the reference charger (100A), the target charger (100B), and the processor (220), the type of communication protocol is not particularly limited.

[0047] The communication unit (210) may include a first communication channel and a second communication channel, and the two communication channels may be individually connected by wire and / or wirelessly to a communication port of a reference charger (100A) and a communication port of a target charger (100B).

[0048] The communication unit (210) can collect reference measurement information from the reference charger / discharger (100A) through the first communication channel. The communication unit (210) can collect target measurement information from the target charger / discharger (100B) through the second communication channel.

[0049] The reference measurement information may indicate the measurement results for the charge / discharge information of the first battery (B1) while a charge / discharge test is performed on the first battery (B1) by the reference charger / discharger (100A).

[0050] The target measurement information may represent the measurement results for charge / discharge information of the second battery (B2) while a charge / discharge test is performed on the second battery (B2) by the reference charger / discharger (100A).

[0051] The first battery (B1) and the second battery (B2) may be previously verified to have identical electrochemical characteristics.

[0052] A charge-discharge test may refer to a test that repeats a charge-discharge cycle a predetermined number of times (e.g., 600). A charge-discharge cycle includes a charge procedure and a discharge procedure. In the same charge-discharge cycle, a rest period (a first rest period) may be provided between the charge procedure and the discharge procedure. In addition, a rest period (a second rest period) may be provided between the discharge procedure of one charge-discharge cycle and the charge procedure of the next charge-discharge cycle. A rest period refers to a period during which both charging and discharging are stopped.

[0053] The charging procedure may be a procedure for charging a battery according to a CC-CV charging protocol over a predetermined voltage range. The CC charging of the charging procedure may be set to a current of a first current rate (e.g., 0.05 C). The CC charging may proceed until the voltage of the battery reaches an upper limit (a predetermined cut-off voltage) from a lower limit of the predetermined voltage range, and then may switch to CV charging. The CV charging may proceed from when the voltage of the battery reaches the cut-off voltage until the charging current of the battery decreases below the predetermined cut-off current. The cut-off current may be, for example, 1 / 10 of the current rate used for CC charging.

[0054] The discharge procedure may be a constant current discharge procedure for discharging the battery over a predetermined voltage range. The CC discharge of the discharge procedure may be set to a current of a second current rate (e.g., 0.33 C). The second current rate may be greater than the first current rate. For example, the first current rate = 0.05 C, the second current rate = 0.33 C.

[0055] The processor (220) may be implemented in hardware using at least one of application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), microprocessors, and other electrical components for performing functions.

[0056] The processor (220) may have a built-in memory (221). The memory (221) may include at least one type of storage medium among, for example, a flash memory type, a hard disk type, an SSD (Solid State Disk type), an SDD (Silicon Disk Drive type), a multimedia card micro type, a random access memory (RAM), a static random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), and a programmable read-only memory (PROM). The memory (221) may store data and programs required for the operations described below by the processor (220). The memory may store data indicating the results of the operations performed by the processor (220).

[0057] The processor (220) can control the communication unit (210) to individually transmit operation commands to the reference charger / discharger (100A) and the target charger / discharger (100B). The reference charger / discharger (100A) can, in response to the operation command, perform a charge / discharge test on the first battery (B1) and then transmit reference measurement information to the calibration device (200). The target charger / discharger (100B), in response to the operation command, can perform a charge / discharge test on the second battery (B2) and then transmit target measurement information to the calibration device (200).

[0058] Each of the reference measurement information and the target measurement information may include a measurement data set (at least one of a cumulative charge capacity value, a cumulative discharge capacity value, a cumulative charge / discharge capacity value, and a charge / discharge efficiency value) for each charge / discharge cycle of a reference number. The set number may be equal to a value obtained by multiplying the reference number by a reference value (which may be a predetermined natural number). For example, the set number = 600, the reference number = 100. The set number may be predetermined so as not to cause aging of the reference charger / discharger (100A) and the target charger / discharger (100B) beyond a critical level.

[0059] The measurement data set for each of the reference number of charge / discharge cycles may be based on at least one of the sum of the charge capacity values ​​and the sum of the discharge capacity values ​​measured in the charge procedures and discharge procedures of the same charge / discharge cycles. For reference, the charge capacity value in a given charge process may be determined by ampere counting, which periodically integrates the measured values ​​of the charge current in the given charge process. Similarly, the discharge capacity value in a given discharge process may be determined by ampere counting, which periodically integrates the measured values ​​of the discharge current in the given discharge process.

[0060] For example, the accumulated charge capacity values ​​of the first to 100th charge / discharge cycles may represent the total charge capacity supplied to the battery through the charging procedure performed 100 times in the first to 100th charge / discharge cycles. The accumulated discharge capacity values ​​of the first to 100th charge / discharge cycles may represent the total discharge capacity extracted from the battery through the discharging procedure performed 100 times in the first to 100th charge / discharge cycles. The accumulated charge / discharge capacity values ​​of the first to 100th charge / discharge cycles may represent the difference (e.g., 0.02 Ah) between the accumulated charge capacity values ​​(e.g., 0.30 Ah) in the first to 100th charge / discharge cycles and the accumulated discharge capacity values ​​(e.g., 0.28 Ah) in the first to 100th charge / discharge cycles. The charge / discharge efficiency values ​​of the first to 100th charge / discharge cycles may represent the ratio of one of the cumulative charge capacity value and the cumulative discharge capacity value to the other, and may also be referred to as the 'Coulombic efficiency'.

[0061] Each of the reference measurement information and the target measurement information may include the same number of accumulated charge capacity values, accumulated discharge capacity values, accumulated charge / discharge capacity values, and / or charge / discharge efficiency values ​​as the reference value.

[0062] The reference measurement information may include at least one of first charge capacity information, first discharge capacity information, first charge / discharge capacity information, and first charge / discharge efficiency information. The first charge capacity information, first discharge capacity information, first charge / discharge capacity information, and first charge / discharge efficiency information may individually indicate the cumulative charge capacity value, cumulative discharge capacity value, cumulative charge / discharge capacity value, and charge / discharge efficiency value of the first battery (B1) through a charge / discharge test.

[0063] The target measurement information may include at least one of second charge capacity information, second discharge capacity information, second charge / discharge capacity information, and second charge / discharge efficiency information. The second charge capacity information, second discharge capacity information, second charge / discharge capacity information, and second charge / discharge efficiency information may individually indicate the cumulative charge capacity value, cumulative discharge capacity value, cumulative charge / discharge capacity value, and charge / discharge efficiency value of the second battery (B2) through a charge / discharge test.

[0064] Fig. 2 is a drawing exemplarily showing the configuration of a charger / discharger. The description of the charger / discharger (100) to be described below with reference to Fig. 2 may be common to the reference charger / discharger (100A) and the target charger / discharger (100B) illustrated in Fig. 1.

[0065] Referring to FIG. 2, the charger / discharger (100) includes a measuring unit (110), a charging / discharging unit (120), and a charging / discharging controller (130).

[0066] The charging / discharging unit (120) is provided to perform repeated charging / discharging cycles for the battery (B). The battery (B) may correspond to the first battery (B1) or the second battery (B1) of Fig. 1.

[0067] The charging / discharging unit (120) has a charging function, a discharging function, and a resting function, and is configured to selectively execute one of the charging function, the discharging function, and the resting function according to the protocol and execution conditions of each of the charging procedure and the discharging procedure specified in the charging / discharging test.

[0068] The charging / discharging unit (120) includes a power circuit (121) and a charging / discharging circuit (122).

[0069] The power circuit (121) is configured to convert power supplied from an AC power source and / or a DC power source into a DC having a predetermined voltage level that meets the input specifications of the charging / discharging circuit (122). One or a combination of two of a known AC-DC converter and a DC-DC converter can be used as the power circuit (121).

[0070] The charge / discharge circuit (122) has a pair of charge / discharge terminals (+, -) connected to the positive and negative poles of the battery (B), respectively, and can charge or discharge the battery (B) according to a command from the charge / discharge controller (130). One or a combination of two of a known constant current circuit and a constant voltage circuit can be used as the charge / discharge circuit (122).

[0071] When an operation command is received through a communication port provided therein, the charge / discharge controller (130) controls the charge / discharge circuit (122) and the power circuit (121) so that the charge / discharge cycle is repeated a set number of times.

[0072] The measuring unit (110) can measure the battery parameters of the battery while the charge / discharge test by the charge / discharge unit (120) is in progress and transmit the measured values ​​to the charge / discharge controller (130).

[0073] The measuring unit (110) includes a voltage sensor (111) and a current sensor (112). The voltage sensor (111) is connected to the positive and negative poles of the battery through a pair of voltage sensing lines, measures the voltage of the battery, and generates (outputs) a signal representing a sample value of the measured voltage.

[0074] The current sensor (112) is installed in the charging / discharging path connecting the battery and the charging / discharging circuit (122), measures the charging current and / or the discharging current, and generates (outputs) a signal representing a sample value of the measured current. For example, the current sensor (112) may include a known current detection element such as a shunt resistor and / or a Hall sensor. The voltage sensor (111) and the current sensor (112) may be integrated in the form of a single chip.

[0075] The charge / discharge controller (130) is operably coupled to the measuring unit (110) and the charge / discharge unit (120). The fact that the two components are operably coupled means that the two components are directly or indirectly connected so that signals can be transmitted and received in one direction or both directions.

[0076] The charge / discharge controller (130) can be implemented in hardware using at least one of ASICs (application specific integrated circuits), DSPs (digital signal processors), DSPDs (digital signal processing devices), PLDs (programmable logic devices), FPGAs (field programmable gate arrays), microprocessors (220), and other electrical components for performing functions.

[0077] The charge / discharge controller (130) may have built-in memory. The memory may include, for example, at least one type of storage medium among a flash memory type, a hard disk type, a solid state disk type, an SDD type, a multimedia card micro type, a random access memory (RAM), a static random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), and a programmable read-only memory (PROM).

[0078] Measurements generated during the charge / discharge test can be recorded in memory. After the charge / discharge test is completed, measurement information including or based on the measured values ​​recorded in memory can be transmitted to the calibration device (200) via the communication port of the charge / discharge controller (130).

[0079] Figure 3 is a drawing used as a reference for comparing the measurement performance of a reference charger / discharger (100A) and a target charger / discharger (100B). To facilitate understanding, among the measurement results for various types of parameters (cumulative charge capacity value, cumulative discharge capacity value, cumulative charge / discharge capacity value, and charge / discharge efficiency value), the cumulative charge / discharge capacity value will be used as a reference for explanation.

[0080] Referring to FIG. 3, a curve (310) illustrates a change in the cumulative charge / discharge capacity value as the charge / discharge cycle of the charge / discharge test for the first battery (B1) is repeated by the reference charger / discharger (100A), and a curve (320) illustrates a change in the cumulative charge / discharge capacity value as the charge / discharge cycle of the charge / discharge test for the second battery (B2) is repeated by the target charger / discharger (100B). For reference, the cycle number may increase by 1 each time the charge / discharge cycle is completed.

[0081] It is noteworthy that the difference in measurement performance between the reference charger / discharger (100A) and the target charger / discharger (100B) is expressed as the difference in the Y-axis value (i.e., cumulative charge / discharge capacity value) between the curves (310) and (320) at the same X-axis value (i.e., cycle number) rather than the individual shapes of the curves (310) and (320). Comparing the curves (310) and (320), it can be confirmed that as the cycle number increases, the difference between the curves (310) and (320) gradually widens in the Y-axis direction.

[0082] (i) If the measured value of the charging current measured by the target charger / discharger (100B) is greater than the actual value, or (ii) if the measured value of the discharging current measured by the target charger / discharger (100B) is less than the actual value, the difference between the curve (310) and the curve (320) may have the tendency illustrated in FIG. 3.

[0083] The inventor of the present invention, through numerous experimental results, has recognized that the difference (based on the Y-axis) between curves (310) and curves (320) has an approximately linear change characteristic with respect to the cycle number.

[0084] Meanwhile, in both curves (310) and (320), the increase in the cumulative charge / discharge capacity value slows down as the cycle number increases. The reasons for this change include, for example, (i) an increase in charge capacity and a decrease in discharge capacity due to the formation of by-products of the charge / discharge reaction, such as SEI (Solid Electrolyte Interphase), in the early stage of the battery's life, and (ii) a decrease in the full charge capacity (FCC) due to battery deterioration.

[0085] Please note that some of the charge capacity supplied to the battery by the charger / discharger may be consumed without being stored in the battery due to heat loss, etc. Therefore, the actual increase in the battery's charge capacity may be less than the charge capacity supplied by the charger / discharger. Furthermore, capacity loss may also occur while the battery is being discharged by the charger / discharger. Therefore, the discharge capacity measured by the charger / discharger may be less than the battery's actual discharge capacity.

[0086] Fig. 4 is a flowchart schematically illustrating a method for calibrating a charger / discharger according to another embodiment of the present invention. The method of Fig. 4 can be executed by the calibration device (200) of Fig. 1.

[0087] Referring to FIGS. 1 to 4, in step S410, the processor (220) controls the communication unit (210) to transmit an operation command to the reference charger / discharger (100A) and the target charger / discharger (100B). The operation command can be transmitted to the reference charger / discharger (100A) and the target charger / discharger (100B) through the first communication channel and the second communication channel of the communication unit (210). By executing step S410, a charge / discharge test of the reference charger / discharger (100A) for the first battery (B1) and a charge / discharge test of the target charger / discharger (100B) for the second battery (B2) are initiated. The operation commands do not have to be transmitted to the reference charger / discharger (100A) and the target charger / discharger (100B) at the same time. For example, the communication unit (210) may first transmit an operation command to the reference charger / discharger (100A) and then transmit the operation command to the target charger / discharger (100B).

[0088] In step S422, the processor (220) obtains (collects) reference measurement information from the reference charger (100A). When the charge / discharge test for the first battery (B1) is completed, the reference charger (100A) can transmit reference measurement information, which is a measurement result for charge / discharge information of the first battery (B1) recorded during the execution period of the charge / discharge test, to the communication unit (210).

[0089] In step S424, the processor (220) acquires (collects) target measurement information from the target charger / discharger (100B). When the charge / discharge test for the second battery (B2) is completed, the reference charger / discharger (100A) can transmit the target measurement information, which is the measurement result for the charge / discharge information of the second battery (B2) recorded during the execution period of the charge / discharge test, to the communication unit (210).

[0090] In step S430, the processor (220) compares the reference measurement information with the target measurement information to generate calibration information for the target charger / discharger (100B). The calibration information may include at least one of a charge capacity calibration value, a discharge capacity calibration value, a charge / discharge capacity calibration value, and a charge / discharge efficiency calibration value.

[0091] When the reference measurement information includes first charge capacity information and the target measurement information includes second charge capacity information, the processor (220) can compare the first charge capacity information and the second charge capacity information to determine a charge capacity correction value. The charge capacity correction value can represent a ratio of one of the two cumulative charge capacity values ​​indicated by the first charge capacity information and the second charge capacity information to the other.

[0092] When the reference measurement information includes first discharge capacity information and the target measurement information includes second discharge capacity information, the processor (220) can compare the first discharge capacity information and the second discharge capacity information to determine a discharge capacity correction value. The discharge capacity correction value can represent a ratio of one of the two cumulative discharge capacity values ​​indicated by the first discharge capacity information and the second discharge capacity information to the other.

[0093] When the reference measurement information includes first charge / discharge capacity information and the target measurement information includes second charge / discharge capacity information, the processor (220) can compare the first charge / discharge capacity information and the second charge / discharge capacity information to determine a charge / discharge capacity correction value. The charge / discharge capacity correction value can represent a ratio of one of the two cumulative charge / discharge capacity values ​​represented by the first charge / discharge capacity information and the second charge / discharge capacity information to the other.

[0094] When the reference measurement information includes first charge / discharge efficiency information and the target measurement information includes second charge / discharge efficiency information, the processor (220) can compare the first charge / discharge efficiency information and the second charge / discharge efficiency information to determine a charge / discharge efficiency correction value. The charge / discharge efficiency correction value can represent a ratio of one of the two cumulative charge / discharge efficiency values ​​represented by the first charge / discharge efficiency information and the second charge / discharge efficiency information to the other.

[0095] The method of FIG. 4 may further include step S440. In step S440, the processor (220) controls the communication unit (210) to transmit a correction command including the correction information determined in step S430 to the target charger / discharger (100B).

[0096] After receiving a calibration command from the calibration device (200), the charge / discharge controller (130) of the target charger / discharger (100B) can correct the measurement information generated during charging / discharging of another battery based on the received calibration information.

[0097] For example, let's say that the charge / discharge efficiency correction value included in the previously received correction information is 97.7%, and the charge / discharge efficiency value of the other battery determined by the target charger / discharger (100B) is 85.4%. Then, the charge / discharge efficiency value of the other battery can be corrected to 85.4×97.7%≒8.34%.

[0098] Meanwhile, as described above, the measurement performance of the target charger / discharger (100B) may gradually deteriorate as the target charger / discharger (100B) ages. Therefore, the validity of the calibration information determined through the method described above with reference to FIG. 4 is naturally not permanent, and thus it is necessary to update the calibration information as the target charger / discharger (100B) ages. However, while the target charger / discharger (100B) is performing the charge / discharge test to obtain new target measurement information required for updating the calibration information, the target charger / discharger (100B) cannot be used for its original purpose (e.g., battery activation). In addition, if the target charger / discharger (100B) performs the charge / discharge test excessively frequently to update the calibration information, there is a concern that the measurement performance of the target charger / discharger (100B) may deteriorate rapidly.

[0099] FIG. 5 is a flowchart schematically illustrating a method for calibrating a charger / discharger according to another embodiment of the present invention. The method of FIG. 5 is a subsequent procedure to step S440 of FIG. 4 and can be executed by the calibration device (200) of FIG. 1.

[0100] The method of FIG. 5 is executed on the condition that the calibration process for the target charger / discharger (100B) according to the method of FIG. 4 has already been executed at least twice. Therefore, when the method of FIG. 5 is executed, previous calibration information is recorded in the memory of the calibration device (200). The previous calibration information may be the calibration information most recently determined by the method of FIG. 4 based on the present time. For example, assuming that m is a natural number greater than or equal to 2, when the method of FIG. 4 is executed a total of m times and the first to mth calibration information are recorded in the memory, the mth calibration information may be 'current calibration information', and the (m-1)th calibration information may be 'previous calibration information'.

[0101] Referring to FIG. 5, in step S510, the processor (220) reads out previous correction information from memory.

[0102] In step S520, the processor (220) may compare the correction information determined in step S440 (which may be referred to as “current correction information”) with previous correction information to determine a validity condition of the correction information determined in step S440. The validity condition may include at least one of a validity time and a valid total charge / discharge capacity.

[0103] If the validity period is included in the validity condition, the validity period becomes unsatisfied when the validity period has elapsed from the time at which the current calibration information was determined. In other words, the current calibration information can be set to be used to calibrate the measurement information of the target charger / discharger (100B) only until the validity period has elapsed from the time at which the current calibration information was determined.

[0104] If the effective total charge / discharge capacity is included in the valid condition, when the increase in the total charge / discharge capacity of the target charger / discharger (100B) reaches the effective total charge / discharge capacity, the valid condition becomes unsatisfied. That is, the current calibration information can be set to be used to calibrate the measurement information of the target charger / discharger (100B) only until the increase in the total charge / discharge capacity of the target charger / discharger (100B) from the time point of determining the current calibration information reaches the effective total charge / discharge capacity.

[0105] In step S530, the processor (220) compares the calibration information determined in step S440 (which may be referred to as “current calibration information”) with previous calibration information to generate preliminary calibration information for the target charger / discharger (100B). The preliminary calibration information may be used to calibrate the measurement information of the target charger / discharger (100B) from a future uncertain time when the current calibration information ceases to satisfy the above-mentioned validity conditions.

[0106] In detail, as with the current calibration information, the preliminary calibration information includes a calibration value for at least one type of charge capacity information, discharge capacity information, charge / discharge capacity information, and charge / discharge efficiency information.

[0107] Since the measurement performance of the target charger (100B) deteriorates due to aging, the correction value for a specific type of measurement information included in the preliminary calibration information may be greater than the correction value for the same type of measurement information included in the current calibration information.

[0108] Each of the valid conditions and the preliminary calibration information may be determined based on the difference between two specific types of calibration values ​​indicated by the previous calibration information and the current calibration information. Furthermore, each of the valid conditions and the preliminary calibration information may be further determined based on at least one of the length of the operating period from the time point of determining the previous calibration information to the time point of determining the current calibration information and the total charge / discharge capacity of the target charger / discharger (100B) during the operating period.

[0109] For any given period, the total charge / discharge capacity, unlike the cumulative charge / discharge capacity, can represent the sum of the cumulative charge capacity and the cumulative discharge capacity. For example, if the cumulative charge capacity for a given period is 10 Ah and the cumulative discharge capacity is 9 Ah, the cumulative charge / discharge capacity is 1 Ah, while the total charge / discharge capacity is 11 Ah.

[0110] The formulas below are intended to exemplify the relationship between at least two of the previous correction information, the current correction information, the validity condition, and the preliminary correction information.

[0111] <Formula 1>

[0112]

[0113] In Equation 1, E is the difference between two calibration values ​​for a specific type of measurement information indicated by the previous calibration information and the current calibration information (i.e., the measurement error of the target charger / discharger (100B)), Δt is the time length of the operation period, ΔQ is the total charge / discharge capacity of the target charger / discharger (100B) during the operation period, and t validrepresents the effective time. f1, f2, and f3 are functions that individually define the negative correspondence between input and output values, and the unit of output for each function is time. As the input value E increases, f1 outputs a small time value, as the input value Δt increases, f2 outputs a small time value, and as the input value ΔQ increases, f3 can output a small time value. The sum of the time values ​​output from f1, f2, and f3 is t valid can be decided by

[0114] <Formula 2>

[0115]

[0116] In Equation 2, E, Δt and ΔQ as individual input values ​​for functions f4, f5 and f6 are the same as in Equation 1, and ΔQ valid represents the effective total charge / discharge capacity. f4, f5, and f6 are functions that individually define the negative correspondence between the input value and the output, and the unit of the output value for each function is capacity. As the input value E increases, f4 outputs a smaller capacity value, as the input value Δt increases, f5 outputs a smaller capacity value, and as the input value ΔQ increases, f6 can output a smaller capacity value. The sum of the capacities output from f4, f5, and f6 is ΔQ valid can be decided by

[0117] <Formula 3>

[0118]

[0119] In Equation 3, E, Δt, and ΔQ as individual input values ​​for functions f7, f8, and f9 are the same as in Equation 1. ΔC current represents the correction value for the specific type of measurement information included in the current correction information, and ΔC pre represents the correction value for the specific type of measurement information included in the preliminary correction information. Functions f7, f8, and f9 are functions that individually define the positive correspondence between input and output values, and the unit of the output value for each function is ΔC.current The unit is the same as that of . As the input value E increases, f7 outputs a large correction value. As the input value Δt increases, f8 outputs a large correction value. As the input value ΔQ increases, f9 can output a large correction value. The sum of the correction values ​​output from f7, f8, and f9 is ΔC. pre can be decided by

[0120] At least one of the valid conditions determined in step S520 and the preliminary correction information determined in step S530 may be included in the correction command and transmitted to the target charger / discharger (100B) in step S440.

[0121] If the validity condition of the received calibration information is not satisfied, the target charger (100B) can transmit a message to the calibration device (200) notifying that the calibration information needs to be updated.

[0122] The embodiments of the present invention described above are not implemented only through devices and methods, but may also be implemented through a program that realizes a function corresponding to the configuration of the embodiments of the present invention or a recording medium on which the program is recorded, and such implementation can be easily implemented by an expert in the technical field to which the present invention belongs based on the description of the embodiments described above.

[0123] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical idea of ​​the present invention and the equivalent scope of the patent claims to be described below by a person having ordinary skill in the art to which the present invention pertains.

[0124] In addition, the present invention described above is not limited to the above-described embodiments and the attached drawings, and all or part of each embodiment may be selectively combined and configured so that various modifications can be made, as those skilled in the art can make various substitutions, modifications, and changes within the scope of the technical idea of ​​the present invention.

Claims

1. In a calibration method for a charger, A step of acquiring reference measurement information, which is a measurement result of charge / discharge information of a first battery while a charge / discharge test is performed on the first battery by the reference charger / discharger, from the reference charger / discharger; A step of acquiring target measurement information, which is a measurement result for charge / discharge information of the second battery while the charge / discharge test is performed on the second battery by the target charger / discharger, from the target charger / discharger; and A step of generating correction information for the target charger / discharger by comparing the reference measurement information with the target measurement information; A method for correcting a charging / discharging battery, comprising:

2. In paragraph 1, The above reference measurement information includes first charge capacity information of the first battery according to the charging procedure of the charge / discharge test, A method for calibrating a charger / discharger, wherein the target measurement information includes second charge capacity information of the second battery according to the charging procedure of the charge / discharge test.

3. In paragraph 2, The step of generating correction information for the above target charger / discharger is as follows: A step of comparing the first charging capacity information and the second charging capacity information to determine a charging capacity correction value included in the correction information; A method for correcting a charging / discharging battery, comprising:

4. In paragraph 1, The above reference measurement information includes first discharge capacity information of the first battery according to the discharge procedure of the charge / discharge test, A method for calibrating a charger / discharger, wherein the target measurement information includes second discharge capacity information of the second battery according to the discharge procedure of the charge / discharge test.

5. In paragraph 4, The step of generating correction information for the above target charger / discharger is as follows: A step of comparing the first discharge capacity information and the second discharge capacity information to determine a discharge capacity correction value included in the correction information; A method for correcting a charging / discharging battery, comprising:

6. In paragraph 1, The above reference measurement information includes first charge / discharge efficiency information indicating a ratio between the first charge capacity information of the first battery by the charge procedure of the charge / discharge test and the first discharge capacity information of the first battery by the discharge procedure of the charge / discharge test, A method for calibrating a charger / discharger, wherein the target measurement information includes second charge / discharge efficiency information indicating a ratio between second charge capacity information of the second battery by the charge procedure of the charge / discharge test and second discharge capacity information of the second battery by the discharge procedure of the charge / discharge test.

7. In paragraph 6, The step of generating correction information for the above target charger / discharger is as follows: A step of comparing the first charge / discharge efficiency information and the second charge / discharge efficiency information to determine a charge / discharge efficiency correction value included in the correction information; A method for correcting a charging / discharging battery, comprising:

8. In paragraph 1, A step of comparing the above correction information with previous correction information to determine the validity condition of the above correction information; A method for correcting a charging / discharging battery, further comprising:

9. In paragraph 1, A step of comparing the above correction information with previous correction information to generate preliminary correction information for the target charger / discharger; A method for correcting a charging / discharging battery, further comprising:

10. In a correction device for a charger / discharger, A communication unit that acquires reference measurement information, which is a measurement result for charge / discharge information of a first battery during a charge / discharge test on the first battery by the reference charger / discharger, from the reference charger / discharger, and acquires target measurement information, which is a measurement result for charge / discharge information of a second battery during a charge / discharge test on the second battery by the target charger / discharger, from the target charger / discharger; and A processor that compares the reference measurement information with the target measurement information to generate correction information for the target charger / discharger; A charger / discharger correction device, including:

11. In paragraph 10, The above reference measurement information includes first charge / discharge efficiency information indicating a ratio between the first charge capacity information of the first battery by the charge procedure of the charge / discharge test and the first discharge capacity information of the first battery by the discharge procedure of the charge / discharge test, A charger / discharger calibration device, wherein the target measurement information includes second charge / discharge efficiency information indicating a ratio between second charge capacity information of the second battery by the charge procedure of the charge / discharge test and second discharge capacity information of the second battery by the discharge procedure of the charge / discharge test.

12. In paragraph 11, The above processor, A charger / discharger calibration device that compares the first charge / discharge efficiency information and the second charge / discharge efficiency information to determine a charge / discharge efficiency correction value included in the calibration information.

13. In paragraph 10, The above processor, A charger / discharger calibration device that compares the above calibration information with previous calibration information to determine the validity condition of the above calibration information.

14. In paragraph 10, The above processor, A charger / discharger calibration device that compares the above calibration information with previous calibration information to generate preliminary calibration information for the target charger / discharger.

15. A charger / discharger calibration system comprising a charger / discharger calibration device according to any one of claims 10 to 14.

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