Apparatus and method for correcting battery charge / discharge capacity data

Abstract

The present invention discloses an apparatus and method for correcting charge / discharge capacity data of a battery, the apparatus and method comprising: a battery having at least one battery cell that can be charged and discharged; a capacity calculation unit that calculates the charge capacity and discharge capacity of the battery; a capacity difference calculation unit that calculates the difference between the charge capacity and discharge capacity of the battery; a capacity difference average calculation unit that calculates the average value of the difference between the charge capacity and discharge capacity; and a data correction unit that applies a predetermined correction value to the charge capacity value of each cycle when the average value of the difference between the charge capacity and discharge capacity is equal to or greater than a predetermined difference reference value.

Description

[Technical Field]

[0001] The present invention relates to a device and method for correcting battery data, and more particularly to a device and method for correcting battery charge / discharge capacity data, which can correct data errors in charger / discharger tests to ensure accurate data. [Background technology]

[0002] Rechargeable secondary batteries, or batteries, are widely used as a power source for mobile devices such as smartphones. Batteries are also used as a power source for environmentally friendly vehicles such as electric vehicles and hybrid electric vehicles, which are proposed as a solution to address air pollution caused by fossil fuel-based gasoline and diesel vehicles. The diversification of battery applications is progressing rapidly, and batteries are expected to be used in even more fields and products in the future.

[0003] Batteries currently in commercial use include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium-ion batteries, among which lithium-ion batteries have attracted attention due to their advantages of being able to be freely charged and discharged, having almost no memory effect compared to nickel-based batteries, and having a very low self-discharge rate and high energy density. Furthermore, because lithium-ion batteries can be manufactured to be compact and lightweight, they are being used as power sources for mobile devices and are being used in a wide range of applications, even for electric vehicles, and are attracting attention as a next-generation energy storage medium.

[0004] However, with the increase in demand, the energy density of batteries is gradually increasing, and the capacity is becoming higher. However, repeated charging and discharging can increase the amount of heat generated by the battery, which can cause excessive temperature rise and malfunction of the components. Ultimately, this can reduce the operating efficiency of the battery and significantly shorten its lifespan.

[0005] To ensure optimal battery operation and safety, several tests are performed during the battery production process. For example, during battery production, a battery charge / discharge test can be performed using a charger / discharger. In the battery charge / discharge test, the battery cells are charged and discharged using the charger / discharger to measure the charge and discharge capacities, which can then be used to confirm the battery's characteristics. However, if the accuracy of the charger / discharger decreases during the process, the accuracy of the battery cell's charging voltage decreases, resulting in errors in the charger / discharger test data, making the battery test results unreliable. Furthermore, such errors can make it impossible to determine whether the test results are due to the battery cells or the charger / discharger, which can lead to the test being discontinued for safety reasons. This can lead to testers having to retest due to unusable data.

[0006] Relevant prior art includes the following: [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Korean Patent Registration No. 10-1456425 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention provides a device and method for correcting battery charge / discharge capacity data, which can correct data errors in charger / discharger tests to ensure accurate data.

[0009] The present invention provides a device and method for correcting battery charge / discharge capacity data, which can correct data errors in charger / discharger tests by applying a predetermined correction value based on the average value of the difference between the charge capacity and discharge capacity of the battery. [Means for solving the problem]

[0010] A battery charge / discharge capacity data correction device according to one embodiment of the present invention comprises a battery having at least one battery cell that can be charged and discharged, a capacity calculation unit that calculates the charge capacity and discharge capacity of the battery, a capacity difference calculation unit that calculates the difference between the charge capacity and discharge capacity of the battery, a capacity difference average calculation unit that calculates the average value of the differences between the charge capacity and discharge capacity, and a data correction unit that applies a predetermined correction value to the charge capacity value of each cycle when the average value of the differences between the charge capacity and discharge capacity is equal to or greater than a predetermined difference reference value.

[0011] The battery comprises a battery module or a battery pack.

[0012] The battery further includes a charge / discharge module for charging and discharging the battery, and a measurement unit for measuring the voltage and current of the battery.

[0013] The charge / discharge module charges and discharges the battery during a plurality of cycles, each cycle consisting of charge, hold, discharge, and hold.

[0014] The capacity calculation unit calculates the charge capacity and the discharge capacity of the battery for each cycle during a plurality of cycles.

[0015] The capacity difference calculation unit receives the charge capacity and the discharge capacity for each cycle from the capacity calculation unit and calculates the difference therebetween, and calculates the difference between the charge capacity and the discharge capacity for each cycle during a plurality of cycles.

[0016] The capacity difference average calculation unit calculates an average value of the difference between the charge capacity and the discharge capacity in at least some of the charge / discharge cycles among a plurality of charge / discharge cycles.

[0017] The reference value is between 0.1 Ah and 0.5 Ah, and the correction value is between 0.5 Ah and 1.5 Ah.

[0018] When the average value of the differences is equal to or greater than the reference difference value, the data correction unit subtracts a predetermined correction value from the charge capacity value of each cycle.

[0019] A method for correcting charge / discharge capacity data of a battery according to another aspect of the present invention includes the steps of charging and discharging a battery having at least one battery cell that can be charged and discharged; calculating the charge capacity and discharge capacity of the battery; repeatedly measuring the charge capacity and discharge capacity over a plurality of cycles to obtain charge / discharge capacity data of the battery; calculating the difference between the charge capacity and discharge capacity for each cycle; calculating an average value of the difference between the charge capacity and discharge capacity over a predetermined number of cycles; and comparing the average value of the difference with a predetermined reference value, and correcting the charge capacity data for each cycle if the average value of the difference is greater than the reference value.

[0020] The battery comprises a battery module or a battery pack.

[0021] The battery is charged and discharged over a number of cycles, each cycle consisting of charging, holding, discharging and holding.

[0022] The charge and discharge capacities of the battery are calculated for each cycle during multiple charge and discharge cycles.

[0023] The difference between the charge capacity and the discharge capacity is calculated for each cycle during multiple cycles.

[0024] The reference value is between 0.1 Ah and 0.5 Ah, and the correction value is between 0.5 Ah and 1.5 Ah.

[0025] If the average value of the difference is equal to or greater than the reference difference value, a predetermined correction value is subtracted from the charge capacity data for each cycle. [Effects of the Invention]

[0026] According to one embodiment of the present invention, an apparatus and method for correcting battery capacity data calculates the charge and discharge capacities of a battery, calculates the difference between the charge and discharge capacities of the battery for each charge and discharge cycle to obtain charge and discharge capacity data for the battery during a predetermined cycle, calculates an average value of the difference between the charge and discharge capacities during the predetermined cycle, and corrects the data by subtracting a predetermined correction value from the charge capacity value for each cycle if the average value of the difference between the charge and discharge capacities during the predetermined cycle is equal to or greater than a predetermined reference value. That is, according to one embodiment of the present invention, if the average value of the difference between the charge and discharge capacities during the predetermined cycle is equal to or greater than a reference value, the data is corrected by subtracting a predetermined correction value from the charge capacity value for each cycle. Therefore, the present invention can correct data errors in charger / discharger tests, thereby improving the reliability of battery tests. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a block diagram illustrating a device for correcting battery charge / discharge capacity data according to an embodiment of the present invention; [Figure 2] FIG. 2 is a block diagram illustrating a method for correcting charge / discharge capacity data of a battery according to an embodiment of the present invention. [Figure 3] 1 is a graph showing the difference between charge capacity and discharge capacity for each charge / discharge cycle. [Figure 4] 10 is a graph showing the average value of the difference between the charge capacity and the discharge capacity of a battery and the result of applying a correction according to the average value. [Figure 5] This is raw data showing the charge capacity for each charge / discharge cycle and the charge capacity before and after correction. DETAILED DESCRIPTION OF THE INVENTION

[0028] Hereinafter, a device for correcting charge / discharge capacity data of a battery according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and may be embodied in various different forms. These embodiments are provided merely to complete the disclosure of the present invention and to fully convey the scope of the invention to those skilled in the art. In the drawings, the thickness of various layers and regions is exaggerated to clearly show them, and the same reference numerals throughout the drawings refer to the same components.

[0029] FIG. 1 is a block diagram illustrating a device for correcting battery charge / discharge capacity data according to one embodiment of the present invention.

[0030] 1, an apparatus for correcting charge and discharge capacity data of a battery according to an embodiment of the present invention may include a battery 100 having at least one chargeable and dischargeable battery cell, a charge and discharge module 200 for charging and discharging the battery 100, a measurement unit 300 for measuring the voltage, current, and other conditions of the battery 100, a capacity calculation unit 400 for calculating the charge and discharge capacities of the battery 100 using the conditions of the battery 100, a capacity difference calculation unit 500 for calculating the difference between the charge and discharge capacities of the battery in each charge and discharge cycle, a capacity difference average calculation unit 600 for calculating the average value of the difference between the charge and discharge capacities for a predetermined cycle, and a data correction unit 700 for subtracting a predetermined correction value from the charge capacity value for each cycle if the average value of the difference between the charge and discharge capacities for a predetermined cycle is equal to or greater than a predetermined difference reference value. Each component of the apparatus for correcting charge and discharge capacity data of a battery according to an embodiment of the present invention will be described in more detail below.

[0031] 1. Battery The battery 100 can be tested by placing it on a predetermined mounting portion (not shown). In this case, the battery 100 may include a battery cell as a target for testing. At least one battery cell may be placed on the mounting portion. That is, one or more battery cells may be placed on the mounting portion and at least one battery cell may be tested. The battery cell may include an electrode assembly including a first electrode, a second electrode, and a separator sandwiched therebetween, and a battery can that houses the electrode assembly. That is, the battery cell may be configured by housing the electrode assembly in the battery can. In this case, one of the first and second electrodes may be a positive electrode, and the other may be a negative electrode. For example, the electrode assembly may include a positive electrode plate formed by applying a positive electrode active material to a positive electrode current collector, a negative electrode plate formed by applying a negative electrode active material to a negative electrode current collector, and a separator sandwiched between the positive and negative electrode plates to prevent short-circuiting between the two plates and enable the movement of lithium ions. In this case, either one of the first and second electrodes may be a positive electrode plate and the other may be a negative electrode plate, or the positive electrode plate may be the first electrode and the negative electrode plate may be the second electrode. The electrode assembly may have, for example, a jelly-roll structure. That is, the electrode assembly may be manufactured by stacking sheet-shaped positive and negative electrode plates at least once with a separator interposed therebetween to form a stack, and then winding the stack around the center of the winding.

[0032] Meanwhile, the battery 100 of the present invention may include a battery module or a battery pack. That is, a plurality of battery cells may form a battery module, or two or more battery modules may form a battery pack, and the present invention can also test the battery module or battery pack. When a plurality of battery cells form a battery module or a battery pack, the plurality of battery cells can be connected in series and / or in parallel by various methods. Meanwhile, the type of battery cell, which is the basic unit that forms the battery 100, is not particularly limited and can be, for example, a lithium ion battery, a lithium polymer battery, a nickel cadmium battery, a nickel metal hydride battery, a nickel zinc battery, etc.

[0033] 2.Charging and discharging module The charge / discharge module 200 can charge and discharge the battery 100. That is, to test the charge / discharge of the battery 100 having at least one battery cell, a specific charge / discharge module 200 can be used to charge or discharge the battery 100. The charge / discharge module 200 can charge the battery 100, hold it for a predetermined time, discharge it, and hold it for a predetermined time. That is, the charge / discharge module 200 can charge and discharge the battery 100 through multiple cycles, with charge, hold, discharge, and hold being one cycle, thereby performing a charge / discharge test of the battery 100. Here, to charge the battery 100, a specific voltage can be applied to the battery 100 using the charge / discharge module 200, and to discharge the battery 100, for example, a ground voltage can be applied to the battery 100 using the charge / discharge module 200. Charging, discharging, and holding using the charge / discharge module 200 can be performed for a time set in the charge / discharge module 200. That is, the charge / discharge module 200 applies a predetermined current and voltage for a predetermined time to charge the battery 100, and cuts off the supply of power to the battery 100 for a predetermined time to maintain the charged state. The charge / discharge module 200 also applies a ground voltage for a predetermined time to discharge the battery 100, and cuts off the supply of power to the battery 100 for a predetermined time to maintain the discharged state. In this way, by using the charge / discharge module 200 to supply and cut off the charging power and supply and cut off the discharging power for predetermined times, the battery 100 can be charged, maintained in a charged state, discharged, and maintained in a discharged state.

[0034] 3.Measuring part The measuring unit 300 may be provided to measure the state of the battery 100. That is, the measuring unit 300 may be connected to the battery 100 placed on the mounting unit to measure the state of the battery 100. In this case, the measuring unit 300 may measure the state of the battery module and battery pack from at least one battery cell. That is, when one or more battery cells are placed on the mounting unit, the measuring unit 300 may measure the state of each battery cell. Also, when at least one battery module or battery pack is placed, the measuring unit 300 may measure the state of each battery module or battery pack. The measuring unit 300 may measure the voltage, current, etc. of the battery 100. To this end, the measuring unit 300 may include a voltage sensor for measuring the voltage and a current sensor for measuring the current. That is, to perform a charge / discharge test on the battery 100 having at least one battery cell, the battery 100 may be charged or discharged using a predetermined charge / discharge module 200. The measuring unit 300 may measure the voltage and current of the battery 100 during charging and discharging. At this time, at least one voltage sensor and at least one current sensor are provided to simultaneously or sequentially measure the state of at least one battery 100 placed on the placement unit.

[0035] 4.Capacity calculation part The capacity calculation unit 400 may calculate the charge capacity and discharge capacity of the battery 100 using the state of the battery 100. For example, the capacity calculation unit 400 may calculate the charge capacity and discharge capacity of the battery 100 using the current and voltage of the battery 100. In this case, the capacity calculation unit 400 may calculate the capacity of the battery 100 using a variety of known techniques. For example, the capacity of a battery cell may be calculated based on the open circuit voltage of the battery cell. The capacity of a battery cell may also be calculated by calculating the amount of current used in a full charge-full discharge cycle. That is, the charge capacity may be calculated by calculating the amount of current applied to the battery 100 when a charging voltage is applied to the battery 100 for a predetermined time to charge the battery 100, and the discharge capacity may be calculated by calculating the amount of current discharged from the battery 100 when a discharging voltage is applied to the battery 100 for a predetermined time to discharge the battery. For example, the charge capacity is 100 Ah when charging at 100 A for one hour, and the discharge capacity is 200 Ah when discharging at 100 A for two hours. In this case, the capacity calculation unit 400 can calculate the charge capacity and discharge capacity of the battery 100 for each cycle. That is, charging the battery 100, holding it for a predetermined time, discharging the battery 100, and holding it for a predetermined time constitute one cycle, and the capacity calculation unit 400 calculates the charge capacity and discharge capacity for the cycle. However, such a charge and discharge cycle can be performed multiple times. For example, if 100 charge and discharge cycles are performed, the capacity calculation unit 400 can calculate the charge capacity and discharge capacity for each cycle to calculate the charge capacity and discharge capacity for the 100 cycles.

[0036] 5.Capacitance difference calculation part The capacity difference calculation unit 500 calculates the difference between the charge capacity and discharge capacity of the battery for each cycle. The capacity calculation unit 400 calculates the charge capacity and discharge capacity of the battery over multiple cycles, while the capacity difference calculation unit 500 receives the charge capacity and discharge capacity from the capacity calculation unit 400 and calculates the difference therebetween. That is, the capacity difference calculation unit 500 receives the charge capacity and discharge capacity for each cycle from the capacity calculation unit 400 and calculates the difference therebetween, thereby calculating the difference between the charge capacity and discharge capacity for each cycle over multiple cycles. For example, if 100 charge and discharge cycles are performed, the capacity difference calculation unit 500 receives the charge capacity and discharge capacity for the 100th cycle from the capacity calculation unit 400 and can calculate the difference between the charge capacity and discharge capacity for each cycle. That is, the capacity difference calculation unit 500 can calculate the difference between the charge capacity and discharge capacity for the 100th cycle.

[0037] 6. Capacity difference average calculation section The capacity difference average calculation unit 600 calculates the average value of the difference between the charge capacity and the discharge capacity over a predetermined number of cycles. The capacity difference average calculation unit 600 receives the difference between the charge capacity and the discharge capacity from the capacity difference calculation unit 500 and calculates the average value of the difference between the charge capacity and the discharge capacity over a predetermined number of cycles. That is, the capacity difference average calculation unit 600 calculates the average value of the difference between the charge capacity and the discharge capacity over some of the multiple charge / discharge cycles. For example, if 100 charge / discharge cycles are performed, the capacity difference average calculation unit 600 can calculate the average value of the difference between the charge capacity and the discharge capacity over 25 charge / discharge cycles. Therefore, from the above example, during the 100 charge / discharge cycles, the capacity difference average calculation unit 600 can calculate the average value of the difference between the charge capacity and the discharge capacity over one to four cycles. Needless to say, the capacity difference average calculation unit 600 can calculate the average value of the charge / discharge capacity difference over not only 25 charge / discharge cycles but also cycles less than the 25 charge / discharge cycles.

[0038] 7. Data Correction Section If the average value of the difference between the charge capacity and the discharge capacity for a predetermined cycle is equal to or greater than a predetermined reference value, the data corrector 700 may correct the data by subtracting a predetermined correction value from the charge capacity value for each cycle. To this end, the data corrector 700 compares the difference between the charge capacity and the discharge capacity for a predetermined cycle provided by the capacity difference average calculator 600 with a reference value. If the result of the comparison indicates that the difference is equal to or greater than the reference value, the data corrector 700 may correct the data by subtracting a predetermined correction value from the charge capacity value for each cycle. Here, the reference value set in the data corrector 700 may be 0.1 Ah to 0.5 Ah, and the correction value may be 0.5 Ah to 1.5 Ah. In an embodiment of the present invention, the reference value may be 0.2 Ah, and the correction value may be 1.0 Ah. For example, if the reference value is 0.2 Ah, the correction value is 1.0 Ah, and the average charge / discharge capacity difference of the battery 100 calculated by the capacity difference average calculation unit 600 is 1.0239 Ah, the average difference is greater than the reference value, so the charge capacity for each cycle can be corrected by subtracting 1.0 Ah. Therefore, the corrected average capacity difference can be 0.0239 Ah. As another example, if the reference value is 0.2 Ah and the average charge / discharge capacity difference of the battery 100 is 0.057 Ah, the average difference is less than the reference value, so no correction is applied.

[0039] Here, the reference value can be derived from the results of multiple charge / discharge tests of the battery 100, but can also be derived from the deviation of the charge / discharge capacity from normal data. For example, if the deviation of the charge / discharge capacity of the battery 100 from normal data is 0.1 Ah or less, a margin of 0.1 Ah can be added to set the reference value to 0.2 Ah. Similarly, the correction value can be derived from the results of multiple charge / discharge tests of the battery 100, but can also be set to a value that converts abnormal data determined to be an error in the charge / discharge device into normal data. On the other hand, the smaller the reference value, the smaller the correction value. In other words, the larger the reference value, the larger the correction value. For example, if the reference value is 0.1 Ah, the correction value is 0.5 Ah. As the reference value increases, the correction value increases; for example, if the reference value is 0.5 Ah, the correction value may be 1.5 Ah. In this case, the smaller the reference value and correction value, the more accurate the data correction can be. Needless to say, the reference value and the correction value may be set differently depending on the capacity of the battery 100, etc. The smaller the capacity of the battery 100, the smaller the reference value and the correction value may be, and the larger the capacity of the battery 100, the smaller the reference value and the correction value may be. For example, the reference value and the correction value may be larger when testing a battery module than when testing a battery cell, and the reference value and the correction value may be larger when testing a battery pack than when testing a battery module.

[0040] Fig. 2 is a flowchart illustrating a method for correcting battery charge / discharge capacity data according to one embodiment of the present invention, that is, Fig. 2 is a flowchart illustrating a correction method using the battery charge / discharge capacity data correction device of Fig. 1.

[0041] 2, a method for correcting charge and discharge capacity data of a battery according to an embodiment of the present invention may include charging and discharging the battery (S110), calculating the charge and discharge capacities of the battery (S120), repeatedly measuring the charge and discharge capacities for a predetermined number of cycles to obtain charge and discharge capacity data of the battery for the predetermined number of cycles (S130), calculating the difference between the charge and discharge capacities for each cycle (S140), calculating an average value of the differences between the charge and discharge capacities for the predetermined number of cycles (S150), and comparing the calculated average value of the differences with a predetermined reference value (S160), and correcting the charge capacity data for each cycle if the average value of the differences is greater than the reference value (S170). Each step of the method for correcting charge and discharge capacity data of a battery according to an embodiment of the present invention will be described in more detail below.

[0042] S110: After placing the battery 100 on a predetermined placement unit, the battery 100 is charged and discharged using the charge / discharge module 200. At this time, the battery 100 may include a battery cell as a target for testing. That is, one or more battery cells may be placed on the placement unit and at least one battery cell may be tested. Meanwhile, the battery 100 of the present invention may include a battery module or a battery pack. The battery 100 may also be charged and discharged using the charge / discharge module 200. The charge / discharge module 200 may charge the battery 100, hold it for a predetermined time, discharge it, and hold it for a predetermined time. That is, the charge / discharge module 200 may charge and discharge the battery 100 through a plurality of cycles, with charge, hold, discharge, and hold being one cycle, thereby performing a charge / discharge test on the battery 100.

[0043] S120: After measuring the state of the battery 100 using the measurement unit 300, the charge capacity and discharge capacity of the battery 100 are calculated using the capacity calculation unit 400. The battery 100 is charged and discharged using the charge / discharge module 200, and the state of the battery 100 is measured using the measurement unit 300. That is, the measurement unit 300 may measure the voltage and current of the battery 100 when charging and the voltage and current when discharging. The capacity calculation unit 400 may calculate the charge capacity and discharge capacity of the battery 100 using the state of the battery 100. For example, the capacity calculation unit 400 may calculate the charge capacity and discharge capacity of the battery 100 using the current and voltage of the battery 100. In this case, the capacity calculation unit 400 may calculate the capacity of the battery cell by calculating the amount of current used in, for example, a full charge / full discharge cycle. That is, when charging battery 100 by applying a charging voltage for a predetermined time, the charge capacity can be calculated by calculating the amount of current applied to battery 100, and when discharging battery 100 by applying a discharging voltage for a predetermined time, the discharge capacity can be calculated by calculating the amount of current discharged from battery 100. For example, when charging at 100 A for one hour, the charge capacity is 100 Ah, and when discharging at 100 A for two hours, the discharge capacity is 200 Ah.

[0044] S130: Acquires charge / discharge capacity data of the battery for a predetermined cycle. The capacity calculation unit 400 can calculate the charge capacity and discharge capacity of the battery 100 for each cycle. That is, charging the battery 100, holding it for a predetermined time, discharging the battery 100, and holding it for a predetermined time constitute one cycle, and the battery 100 is charged and discharged, and the charge capacity and discharge capacity for the cycle are calculated. However, such charge / discharge cycles can be performed multiple times. For example, if 100 charge / discharge cycles are performed, the capacity calculation unit 400 can calculate the charge capacity and discharge capacity for each cycle to calculate the charge capacity and discharge capacity for the 100 cycles.

[0045] S140: Calculate the difference between the charge capacity and the discharge capacity for each cycle using the capacity difference calculation unit 500. The capacity calculation unit 400 calculates the charge capacity and the discharge capacity of the battery during multiple cycles, and the capacity difference calculation unit 500 receives the charge capacity and the discharge capacity from the capacity calculation unit 400 and calculates the difference therebetween. That is, the capacity difference calculation unit 500 receives the charge capacity and the discharge capacity for each cycle from the capacity calculation unit 400 and calculates the difference therebetween, thereby calculating the difference between the charge capacity and the discharge capacity for each cycle during the multiple cycles. For example, if 100 charge and discharge cycles are performed, the capacity difference calculation unit 500 receives the charge capacity and the discharge capacity for the 100th cycle from the capacity calculation unit 400 and can calculate the difference between the charge capacity and the discharge capacity for each cycle. That is, the capacity difference calculation unit 500 can calculate the difference between the charge capacity and the discharge capacity for the 100th cycle.

[0046] S150: The capacity difference average calculation unit 600 calculates the average value of the difference between the charge capacity and the discharge capacity for a predetermined number of cycles. The capacity difference average calculation unit 600 receives the difference between the charge capacity and the discharge capacity from the capacity difference calculation unit 500 and calculates the average value of the difference between the charge capacity and the discharge capacity for a predetermined number of cycles. That is, the capacity difference average calculation unit 600 calculates the average value of the difference between the charge capacity and the discharge capacity for some of the multiple charge / discharge cycles. For example, if 100 charge / discharge cycles are performed, the capacity difference average calculation unit 600 can calculate the average value of the difference between the charge capacity and the discharge capacity for 25 charge / discharge cycles. Therefore, from the above example, during the 100 charge / discharge cycles, the capacity difference average calculation unit 600 can calculate the average value of the difference between the charge capacity and the discharge capacity for one to four cycles. Needless to say, the capacity difference average calculation unit 600 can calculate the average value of the charge / discharge capacity difference for not only 25 charge / discharge cycles but also cycles less than the number of charge / discharge cycles.

[0047] S160 and S170: The data corrector 700 compares the average value of the difference between the charge capacity and discharge capacity for a predetermined cycle with a predetermined reference value. If the average difference is equal to or greater than the reference value, the data corrector 700 subtracts a predetermined correction value from the charge capacity value for each cycle to correct the data. To this end, the data corrector 700 compares the difference between the charge capacity and discharge capacity for a predetermined cycle provided by the capacity difference average calculator 600 with a reference value. If the result of the comparison indicates that the difference is equal to or greater than the reference value, the data corrector 700 subtracts a predetermined correction value from the charge capacity value for each cycle to correct the data. Here, the reference value set in the data corrector 700 may be 0.1 Ah to 0.5 Ah, and the correction value may be 0.5 Ah to 1.5 Ah. In an embodiment of the present invention, the reference value may be 0.2 Ah, and the correction value may be 1.0 Ah. For example, if the reference value is 0.2 Ah, the correction value is 1.0 Ah, and the average charge / discharge capacity difference of the battery 100 calculated by the capacity difference average calculation unit 600 is 1.0239 Ah, the average difference is greater than the reference value, so the charge capacity for each cycle can be corrected by subtracting 1.0 Ah. Therefore, the corrected average capacity difference can be 0.0239 Ah. As another example, if the reference value is 0.2 Ah and the average charge / discharge capacity difference of the battery 100 is 0.057 Ah, the average difference is less than the reference value, so no correction is applied.

[0048] Figure 3 is a graph showing the difference between charge and discharge capacity for each charge / discharge cycle. As shown in Figure 3, normal data lower than 0.2 Ah and erroneous data higher than 0.2 Ah are shown. That is, Figure 3 shows normal data with a charge / discharge capacity difference smaller than the reference value of 0.2 Ah and erroneous data with a charge / discharge capacity difference larger than the reference value.

[0049] FIG. 4 is a graph showing the average value of the difference between the charge capacity and discharge capacity of a battery and the results of applying a correction based on the average value. Specifically, FIG. 4(a) is a graph showing a case where the average value of the difference between the charge capacity and discharge capacity is smaller than the reference value, FIG. 4(b) is a graph showing a case where the average value of the difference between the charge capacity and discharge capacity is larger than the reference value, and FIG. 4(c) is a graph showing the result after correction. Here, the reference value is set to 0.2 Ah, and the correction value is set to 1.0 Ah. As shown in FIG. 4(a), in Example 1, the average value of the difference between the charge capacity and discharge capacity is 0.06 Ah, and in Example 2, the average value of the difference between the charge capacity and discharge capacity is 0.04 Ah. In Examples 1 and 2, the average value of the difference is smaller than the reference value of 0.2 Ah, so correction is unnecessary. However, as shown in Figure 4(b), in Example 3, the average difference between charge capacity and discharge capacity is 1.0 Ah, and in Example 4, the average difference between charge capacity and discharge capacity is 0.7 Ah. In Examples 3 and 4, the average difference is even greater than the reference value of 0.2 Ah, so correction is necessary. Therefore, as shown in Figure 4(c), when the correction value of 1.0 Ah is subtracted from Example 3, the average difference becomes 0.02 Ah.

[0050] Figure 5 shows raw data showing the charge capacity for each charge / discharge cycle and the charge capacity before and after correction. As shown in Figure 5, normal #1 and normal #2 are normal data in which the average difference between charge capacity and discharge capacity is lower than the reference value (0.2 Ah), while error #3 and error #4 are error data in which the average difference between charge capacity and discharge capacity is higher than the reference value. Here, normal #1, #2, #3, and #4 each represent a battery cell. That is, normal #1, normal #2, error #3, and error #4 represent normal battery cell 1, normal battery cell 2, error battery cell 3, and error battery cell 4, respectively. Meanwhile, the average difference between charge capacity and discharge capacity for error #3 is 1.0239 Ah, and the average difference between charge capacity and discharge capacity for error #4 is 0.7257 Ah. In Figure 5, #1Cha, #2Cha, #3Cha, and #4Cha indicate the charge capacities before correction, and #1 algorithm, #2 algorithm, #3 algorithm, and #4 algorithm indicate the charge capacities after correction. Here, #1 algorithm and #2 algorithm are normal data in which the average difference between charge capacity and discharge capacity is lower than the reference value, so no correction was performed. #3 algorithm indicates the charge capacity after applying a 1.0 Ah correction value, and #4 algorithm indicates the charge capacity after applying a 0.7 Ah correction value. For example, for 22 cycles, the average differences between normal #1 and normal #2 are 0.100662 and 0.0370026, respectively, and the average differences between error #3 and error #4 are 1.03491 and 0.739883, respectively. Furthermore, the charge capacities before correction for Normal #1, Normal #2, Error #3, and Error #4 are 164.575, 165.786, 166.623, and 166.59, respectively. Since the average difference values ​​for Normal #1 and Normal #2 are even smaller than the reference value, no correction is applied. If correction values ​​of 1.0 Ah and 0.7 Ah are applied to the charge capacity values ​​for Error #3 and Error #4, respectively, the corrected charge capacities will be 165.623 and 165.59, as with the #3 and #4 algorithms.

[0051] As described above, the apparatus and method for correcting battery charge / discharge capacity data according to an embodiment of the present invention calculates the charge and discharge capacities of battery 100 using capacity calculation unit 400, calculates the difference between the charge and discharge capacities of the battery for each charge / discharge cycle using capacity difference calculation unit 500 to obtain charge / discharge capacity data for the battery during a predetermined cycle, calculates the average value of the difference between the charge and discharge capacities during the predetermined cycle using capacity difference average calculation unit 600, and corrects the data by subtracting a predetermined correction value from the charge capacity value for each cycle when the average value of the difference between the charge and discharge capacities during the predetermined cycle is equal to or greater than a predetermined reference value using data correction unit 700. That is, according to the present invention, when the average value of the difference between the charge and discharge capacities during the predetermined cycle is equal to or greater than a reference value, the present invention corrects the data by subtracting a predetermined correction value from the charge capacity value for each cycle. Therefore, the present invention can correct data errors in charger / discharger tests, thereby improving the reliability of battery tests.

[0052] Although the technical concept of the present invention as described above has been specifically described based on the above embodiment, it should be noted that the above embodiment is for the purpose of explanation and not for the purpose of limitation. It should be understood that a person skilled in the art of the present invention can implement various embodiments within the scope of the technical concept of the present invention.

Claims

1. a battery including at least one battery cell that is rechargeable and dischargeable; a capacity calculation unit that calculates the charge capacity and discharge capacity of the battery; a capacity difference calculation unit that calculates a difference between the charge capacity and the discharge capacity of the battery; a capacity difference average calculation unit that calculates an average value of the difference between the charge capacity and the discharge capacity; a data correction unit that applies a predetermined correction value to the charge capacity value of each cycle when the average value of the difference between the charge capacity and the discharge capacity is equal to or greater than a predetermined difference reference value; A battery charge / discharge capacity data correction device comprising:

2. The device for correcting charge / discharge capacity data of a battery according to claim 1 , wherein the battery comprises a battery module or a battery pack.

3. 3. The device for correcting battery charge / discharge capacity data according to claim 1, further comprising: a charge / discharge module for charging and discharging the battery; and a measurement unit for measuring the voltage and current of the battery.

4. 4. The device for correcting charge / discharge capacity data of a battery according to claim 3, wherein the charge / discharge module charges and discharges the battery over a plurality of cycles, each cycle consisting of charging, holding, discharging, and holding again.

5. The device for correcting charge / discharge capacity data of a battery according to claim 4 , wherein the capacity calculation unit calculates the charge capacity and the discharge capacity of the battery for each of the plurality of cycles.

6. 6. The device for correcting charge / discharge capacity data of a battery according to claim 5, wherein the capacity difference calculation unit receives the charge capacity and the discharge capacity for each cycle from the capacity calculation unit and calculates a difference therebetween, and calculates a difference between the charge capacity and the discharge capacity for each cycle during the plurality of cycles.

7. The device for correcting battery charge / discharge capacity data according to claim 6 , wherein the capacity difference average calculation unit calculates an average difference between the charge capacity and the discharge capacity for at least some of the plurality of cycles.

8. 8. The device for correcting battery charge / discharge capacity data according to claim 7, wherein the difference reference value is 0.1 Ah to 0.5 Ah, and the correction value is 0.5 Ah to 1.5 Ah.

9. The device for correcting battery charge / discharge capacity data according to claim 8 , wherein the data corrector subtracts the correction value from the charge capacity value of each cycle when the average difference value is equal to or greater than the reference difference value.

10. Charging and discharging a battery comprising at least one rechargeable and dischargeable battery cell; calculating the charge capacity and discharge capacity of the battery; repeatedly measuring the charge capacity and the discharge capacity for a plurality of cycles to obtain charge and discharge capacity data of the battery; calculating the difference between the charge capacity and the discharge capacity for each cycle; calculating an average difference between the charge capacity and the discharge capacity during a given cycle; comparing the difference average value with a predetermined reference value, and if the difference average value is equal to or greater than the reference value, applying a predetermined correction value to the charge capacity data for each cycle; A method for correcting battery charge / discharge capacity data, including:

11. The method for correcting charge / discharge capacity data of a battery according to claim 10 , wherein the battery comprises a battery module or a battery pack.

12. 12. The method for correcting charge / discharge capacity data of a battery according to claim 10, wherein the battery is charged / discharged over a plurality of cycles, each cycle consisting of charging, holding, discharging, and holding again.

13. The method of claim 12 , wherein the charge capacity and discharge capacity of the battery are calculated for each cycle during the plurality of cycles.

14. The method for correcting battery charge / discharge capacity data according to claim 13 , wherein the difference between the charge capacity and the discharge capacity is calculated for each cycle during the plurality of cycles.

15. 15. The method for correcting battery charge / discharge capacity data according to claim 14, wherein the reference value is 0.1 Ah to 0.5 Ah, and the correction value is 0.5 Ah to 1.5 Ah.

16. The method for correcting battery charge / discharge capacity data according to claim 15, wherein when the average difference value is equal to or greater than the reference value, the correction value is subtracted from the charge capacity data for each cycle.

Images