Method and system for secondary battery activation and capacity calculation

Abstract

The present invention provides a method for secondary battery activation and capacity calculation, the method comprising: a charging process (S510) of charging a secondary battery; an aging process (S520) of aging the secondary battery; a shipping discharge process (S530) performed after the charging process (S510) and the aging process (S520) and including a capacity cut-off process (S532) of performing a first discharge (C1) of the secondary battery by a capacity cut-off method or a voltage cut-off process (S534) of performing a second discharge (C2) of the secondary battery by a voltage cut-off method; and a capacity calculation process (S540) of calculating a process capacity (QP) of the secondary battery by using shipping discharge information including an end voltage (VE), which is the voltage of the secondary battery at the time of capacity cut-off or following capacity cut-off in the capacity cut-off process (S532), or a discharge capacity (QD) of the secondary battery discharged during the voltage cut-off process (S534).

Description

Method and system for activating and calculating the capacity of a secondary battery

[0001] This application claims the benefit of priority from Republic of Korea Patent Application No. 10-2024-0081408, dated June 21, 2024, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to a method and method for activating and calculating the capacity of a secondary battery, and relates to a method and method for activating and calculating the capacity of a secondary battery, which can reduce the time and energy required for activating a secondary battery, reduce the number of chargers and dischargers, reduce voltage distribution, and have a high correlation or similarity between the calculated process capacity and the actual capacity.

[0003] By performing an activation process including a series of processes such as charging, aging, and discharging on an assembled secondary battery, the secondary battery can be activated and stabilized and made usable.

[0004] Conventional activation processes utilize a "shipping" method, where a fully charged secondary battery is fully discharged and then slowly charged at a low current to the shipping state of charge (SOC). Consequently, the voltage distribution across multiple secondary batteries is small.

[0005] Furthermore, the conventional activation process measured the process capacity of a secondary battery by fully charging and then fully discharging, as described above. Therefore, the process capacity of a secondary battery may be highly correlated with or similar to its actual capacity.

[0006] Here, the process capacity is an estimated value of the capacity of a fully charged secondary battery, and the actual capacity may be the actual total capacity of the secondary battery. For example, the actual capacity can be measured by fully discharging a fully charged secondary battery while applying a current smaller than the current applied when measuring the process capacity. The actual capacity may be the discharge capacity of the secondary battery at a specific temperature (e.g., 40 degrees Celsius).

[0007] However, the conventional activation process has the problem of increasing the time required and energy required because it fully charges, fully discharges, and then recharges the secondary battery.

[0008] Prior art related to this is Korean Patent No. 10-1626190.

[0009] The present invention has been devised to solve the above-described problems, and its purpose is to provide a method and method for activating and calculating the capacity of a secondary battery, which can reduce the time and energy required for activating a secondary battery and reduce the number of chargers and dischargers.

[0010] In addition, the purpose is to provide a method and method for activating and calculating capacity of a secondary battery, which can reduce the voltage distribution of multiple secondary batteries.

[0011] In addition, the purpose is to provide a method and method for activating and calculating the capacity of a secondary battery, in which the calculated process capacity has a high correlation with or is similar to the actual capacity of the secondary battery.

[0012] The technical objectives of the present invention are not limited to the purposes mentioned above. Other objectives and advantages of the present invention not mentioned above 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 objectives and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims.

[0013] In order to solve the above-described problem, the present invention provides a method (S500) for activating and calculating capacity of a secondary battery, including a charging process (S510), an aging process (S520), a shipping discharge process (S530), and a capacity calculation process (S540).

[0014] In the above charging process (S510), the secondary battery can be charged.

[0015] In the above aging process (S520), the secondary battery can be aged.

[0016] The above-mentioned discharge process (S530) can be performed after the above-mentioned charging process (S510) and aging process (S520).

[0017] The above discharge process (S530) may include a capacity cut-off process (S532) or a voltage cut-off process (S534).

[0018] In the above capacity cut-off process (S532), the secondary battery can be first discharged (C1) using a capacity cut-off method.

[0019] In the above voltage cut-off process (S534), the secondary battery can be discharged a second time (C2) in a voltage cut-off manner.

[0020] In the above capacity calculation process (S540), the process capacity (QP) of the secondary battery can be calculated using the shipment discharge information.

[0021] The above discharge information may include termination voltage (VE) or discharge capacity (QD).

[0022] The above-mentioned termination voltage (VE) may be the voltage of the secondary battery obtained during or after the capacity cut-off of the capacity cut-off process (S532).

[0023] The above discharge capacity (QD) may be the capacity discharged from the secondary battery during the voltage cut-off process (S534).

[0024] In one embodiment, the discharge process (S530) may include the voltage cutoff process (S534).

[0025] In one embodiment, the discharge process (S530) may include the capacity cutoff process (S532) and the voltage cutoff process (S534).

[0026] In the above capacity calculation process (S540), the process capacity (QP) can be calculated using the delivery discharge information including the termination voltage (VE) and discharge capacity (QD).

[0027] In one embodiment, the capacity cutoff process (S532) may be performed m times (m is a natural number greater than or equal to 2) or the voltage cutoff process (S534) may be performed n times (n is a natural number greater than or equal to 2).

[0028] In the above capacity calculation process (S540), the process capacity (QP) can be calculated using the shipment discharge information that includes at least some of the m termination voltages (VE) or at least some of the n discharge capacities (QD).

[0029] The m above-mentioned termination voltages (VE) can be obtained through the m above-mentioned capacity cut-off process (S532).

[0030] The above n discharge capacities (QD) are n discharge capacities (QD) obtained through the above n voltage cut-off processes (S534).

[0031] In one embodiment, the m may be 2 or the n may be 3.

[0032] In one embodiment, in the m-th capacity cut-off process (S532), the discharge speed of the secondary battery in the i-th capacity cut-off process (S532) (i is a natural number greater than or equal to 1 and less than m) may be greater than the discharge speed of the secondary battery in the i+1-th capacity cut-off process (S532), or in the n-th voltage cut-off process (S534), the discharge speed of the secondary battery in the j-th voltage cut-off process (S534) (j is a natural number greater than or equal to 1 and less than n) may be greater than the discharge speed of the secondary battery in the j+1-th voltage cut-off process (S534).

[0033] In one embodiment, the discharge process (S530) may include the capacity cutoff process (S532) and the voltage cutoff process (S534).

[0034] The above capacity cut-off process (S532) may be performed before the above voltage cut-off process (S534).

[0035] In one embodiment, the discharge speed of the secondary battery in the capacity cut-off process (S532) may be greater than the discharge speed of the secondary battery in the voltage cut-off process (S534).

[0036] In one embodiment, in the capacity calculation process (S540), the process capacity (QP) can be calculated by applying the shipment discharge information to the correlation function.

[0037] The above correlation function can be derived by regression analysis of the shipment discharge information and actual capacity for a plurality of the secondary batteries.

[0038] In addition, in order to solve the above-described problem, the present invention provides a method for activating a secondary battery including a charging process (S510), an aging process (S520), and a shipment discharge process (S530).

[0039] In the above charging process (S510), the secondary battery can be charged.

[0040] In the above aging process (S520), the secondary battery can be aged.

[0041] The above-mentioned discharge process (S530) can be performed after the charging process (S510) and the aging process (S520).

[0042] The above discharge process (S530) may include a voltage cutoff process (S534).

[0043] In the above voltage cut-off process (S534), the secondary battery can be discharged a second time (C2) in a voltage cut-off manner.

[0044] The above voltage cutoff process (S534) can be performed n times (n is a natural number greater than or equal to 2).

[0045] In the above n-th voltage cut-off process (S534), the discharge speed of the secondary battery of the j-th voltage cut-off process (S534) (j is a natural number greater than or equal to 1 and less than n) may be greater than the discharge speed of the secondary battery of the j+1-th voltage cut-off process (S534).

[0046] In addition, in order to solve the above-described problem, the present invention provides a secondary battery activation and capacity calculation system (10) including a charging unit (100), an aging unit (200), a discharge unit (300), and a capacity calculation unit (400).

[0047] The above charging unit (100) can charge the secondary battery.

[0048] The above aging unit (200) can age the secondary battery.

[0049] The above discharge unit (300) can discharge the secondary battery (C1 or C2) in a capacity cut-off manner or a voltage cut-off manner.

[0050] The above capacity calculation unit (400) can calculate the process capacity (QP) of the secondary battery using the shipment discharge information.

[0051] The above discharge information may include termination voltage (VE) or discharge capacity (QD).

[0052] The above-mentioned termination voltage (VE) may be the voltage of the secondary battery obtained at or after the capacity cut-off when the first discharge (C1) is performed using the capacity cut-off method.

[0053] The above discharge capacity (QD) may be the capacity discharged from the secondary battery during the second discharge (C2) using the voltage cut-off method.

[0054] In one embodiment, the discharge unit (300) can perform the second discharge (C2) in the voltage cut-off manner.

[0055] In one embodiment, the discharge unit (300) can discharge (C1, C2) in the capacity cut-off method and the voltage cut-off method.

[0056] The above capacity calculation unit (400) can calculate the process capacity (QP) using the delivery discharge information including the termination voltage (VE) and discharge capacity (QD).

[0057] In one embodiment, the discharge unit (300) can perform a first discharge (C1) m times (m is a natural number greater than or equal to 2) using the capacity cutoff method or a second discharge (C2) n times (n is a natural number greater than or equal to 2) using the voltage cutoff method.

[0058] The above capacity calculation unit (400) can calculate the process capacity (QP) using the delivery discharge information that includes at least some of the m termination voltages (VE) or at least some of the n discharge capacities (QD).

[0059] The m above-mentioned termination voltages (VE) can each be obtained through the m above-mentioned first discharges (C1) of the above-mentioned capacity cut-off method.

[0060] The above n discharge capacities (QD) can be obtained through the n second discharges (C2) of the voltage cutoff method.

[0061] In one embodiment, the m may be 2 or the n may be 3.

[0062] In one embodiment, in the first discharge (C1) of the mth capacity cut-off method, the discharge speed of the i-th first discharge (C1) (i is a natural number greater than or equal to 1 and less than m) may be greater than the discharge speed of the i+1-th first discharge (C1), or in the n-th second discharge (C2) of the voltage cut-off method, the discharge speed of the j-th second discharge (C2) (j is a natural number greater than or equal to 1 and less than n) may be greater than the discharge speed of the j+1-th second discharge (C2).

[0063] In one embodiment, the discharge unit (300) can discharge (C1, C2) in the capacity cut-off method and the voltage cut-off method.

[0064] The above first discharge (C1) may be performed before the above second discharge (C2).

[0065] In one embodiment, the discharge rate of the capacity cut-off method may be greater than the discharge rate of the voltage cut-off method.

[0066] In one embodiment, the capacity calculation unit (400) can calculate the process capacity (QP) by applying the shipment discharge information to a correlation function.

[0067] The above correlation function can be derived by regression analysis of the shipment discharge information and actual capacity for a plurality of the secondary batteries.

[0068] In addition, in order to solve the above-described problem, the present invention provides an activation system for a secondary battery including a charging unit (100), an aging unit (200), and a discharge unit (300).

[0069] The above charging unit (100) can charge a secondary battery.

[0070] The above aging unit (200) can age the secondary battery.

[0071] The above-mentioned discharge unit (300) can discharge the secondary battery a second time (C2) n times (n is a natural number greater than or equal to 2) using a voltage cutoff method.

[0072] In the above n-th second discharge (C2), the discharge speed of the j-th second discharge (C2) (j is a natural number greater than or equal to 1 and less than n) may be greater than the discharge speed of the j+1-th second discharge (C2).

[0073] According to embodiments of the present invention, a method for activating and calculating a capacity of a secondary battery (S500) includes: a charging process (S510) for charging a secondary battery; an aging process (S520) for aging the secondary battery; a shipping discharge process (S530) that is performed after the charging process (S510) and the aging process (S520), and includes a capacity cut-off process (S532) for first discharging (C1) the secondary battery in a capacity cut-off manner or a voltage cut-off process (S534) for second discharging (C2) the secondary battery in a voltage cut-off manner; And it may include a capacity calculation process (S540) for calculating the process capacity (QP) of the secondary battery using the discharge information including the end voltage (VE) which is the voltage of the secondary battery obtained at the time of the capacity cut-off of the capacity cut-off process (S532) or after the capacity cut-off or the discharge capacity (QD) of the secondary battery discharged during the voltage cut-off process (S534).

[0074] Accordingly, the secondary battery activation method is simplified from the conventional full discharge followed by a pre-charge to a pre-discharge, thereby reducing the time and energy required for secondary battery activation and the number of chargers and dischargers required. This can improve secondary battery productivity and reduce manufacturing costs.

[0075] In addition, since the discharge process (S530) can include a voltage cutoff process (S534), unlike the conventional process of fully discharging and then charging, the voltage distribution of multiple secondary batteries can be reduced even when discharged. Accordingly, the uniformity of the secondary batteries is improved, and low-voltage defects can be easily sorted out.

[0076] In addition, since the process capacity (QP) of the secondary battery can be calculated using the end voltage (VE) or discharge capacity (QD) obtained by the capacity or voltage cut-off process (S532, S534), even if the actual capacities (QAs) of multiple secondary batteries are different, the process capacity (QP) of each secondary battery can have a high correlation with or be similar to the actual capacity (QA) (Fig. 6). This may be because the difference in the actual capacities (QAs) of multiple secondary batteries is reflected in the end voltage (VE) or discharge capacity (QD) of the cut-off process (S532, S534). Accordingly, unlike the conventional full discharge, even if the discharge is performed only up to the shipping SOC (i.e., shipping discharge), the reliability of the process capacity (QP) of the secondary battery can be improved.

[0077] According to embodiments of the present invention, the discharge process (S530) may include the voltage cutoff process (S534).

[0078] Accordingly, the voltage distribution of multiple secondary batteries is reduced, the uniformity of the secondary batteries is improved, and low-voltage defects can be easily selected.

[0079] According to embodiments of the present invention, the discharge process (S530) may include the capacity cutoff process (S532) and the voltage cutoff process (S534). In the capacity calculation process (S540), the process capacity (QP) may be calculated using the discharge information including the end voltage (VE) and the discharge capacity (QD).

[0080] Accordingly, since the process capacity (QP) of the secondary battery is calculated using the end voltage (VE) and discharge capacity (QD) obtained through the capacity and voltage cut-off process (S532, S534), the calculated process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA) of the secondary battery.

[0081] According to embodiments of the present invention, the capacity cut-off process (S532) may be performed m times (m is a natural number greater than or equal to 2) or the voltage cut-off process (S534) may be performed n times (n is a natural number greater than or equal to 2). In the capacity calculation process (S540), the process capacity (QP) may be calculated using the shipment discharge information that includes at least some of the m termination voltages (VE) obtained through the m capacity cut-off processes (S532) or includes at least some of the n discharge capacities (QD) obtained through the n voltage cut-off processes (S534).

[0082] Accordingly, since the voltage cut-off process (S534) can be performed multiple times, the voltage distribution of multiple secondary batteries can be effectively reduced. In addition, since the process capacity (QP) can be calculated using multiple end voltages (VE) or multiple discharge capacities (QD), the process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA).

[0083] According to embodiments of the present invention, m may be 2 or n may be 3.

[0084] Accordingly, since m can be 2, the process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA), while at the same time reducing the time required for secondary battery activation. Furthermore, since n can be 3, the process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA), and the voltage distribution of multiple secondary batteries can be further reduced, while at the same time reducing the time required for secondary battery activation.

[0085] According to embodiments of the present invention, in the m-th capacity cut-off process (S532), the discharge speed of the secondary battery in the i-th (i is a natural number greater than or equal to 1 and less than m) capacity cut-off process (S532) may be greater than the discharge speed of the secondary battery in the i+1-th capacity cut-off process (S532), or in the n-th voltage cut-off process (S534), the discharge speed of the secondary battery in the j-th (j is a natural number greater than or equal to 1 and less than n) voltage cut-off process (S534) may be greater than the discharge speed of the secondary battery in the j+1-th voltage cut-off process (S534).

[0086] Accordingly, the discharge speed increases as the cut-off process is performed first, so even if the capacity or voltage cut-off process (S532 or S534) is performed multiple times, the total required time can be reduced.

[0087] In addition, the later the cut-off process is performed, the lower the discharge rate, which reduces the influence of the internal resistance of the secondary battery (e.g., heat generation), so that the discharge can be performed consistently and stably. Accordingly, the accuracy of the cut-off capacity or voltage is improved, and the cut-off state is stably maintained, so that the process capacity (QP) has a high correlation with or is similar to the actual capacity (QA), and the voltage dispersion of multiple secondary batteries can be effectively reduced.

[0088] According to embodiments of the present invention, the discharge process (S530) may include the capacity cutoff process (S532) and the voltage cutoff process (S534). The capacity cutoff process (S532) may be performed before the voltage cutoff process (S534).

[0089] Accordingly, even if the capacity cut-off process (S532) is performed, the voltage distribution of multiple secondary batteries can be effectively reduced through the voltage cut-off process (S534) performed later.

[0090] According to embodiments of the present invention, the discharge speed of the secondary battery in the capacity cut-off process (S532) may be greater than the discharge speed of the secondary battery in the voltage cut-off process (S534).

[0091] Accordingly, since the discharge speed of the capacity cut-off process (S532) is large, the total required time can be reduced even if the capacity and voltage cut-off processes (S532, S534) are performed.

[0092] In addition, since the discharge speed of the voltage cut-off process (S534) is low, the influence of the internal resistance of the secondary battery (e.g., heat generation, etc.) is reduced, so the accuracy of the cut-off voltage is improved and the cut-off voltage can be stably maintained. Accordingly, the voltage distribution of multiple secondary batteries can be effectively reduced.

[0093] According to embodiments of the present invention, in the capacity calculation process (S540), the process capacity (QP) can be calculated by applying the shipment discharge information to a correlation function. The correlation function can be derived by regression analysis of the shipment discharge information and actual capacity for a plurality of secondary batteries.

[0094] Accordingly, the process capacity (QP) can be calculated as an appropriate value that is highly correlated with or similar to the actual capacity (QA) (Fig. 6).

[0095] According to embodiments of the present invention, a method for activating a secondary battery may include a charging process (S510) for charging a secondary battery; an aging process (S520) for aging the secondary battery; and a shipping discharge process (S530) that is performed after the charging process (S510) and the aging process (S520) and includes a voltage cut-off process (S534) for discharging the secondary battery a second time (C2) using a voltage cut-off method. The voltage cut-off process (S534) may be performed n times (n is a natural number greater than or equal to 2). In the n voltage cut-off processes (S534), a discharge rate of the secondary battery in the jth voltage cut-off process (S534) (j is a natural number greater than or equal to 1 and less than n) may be greater than a discharge rate of the secondary battery in the j+1th voltage cut-off process (S534).

[0096] Accordingly, the secondary battery activation method can be simplified from the conventional full discharge followed by a pre-charge to a pre-discharge, thereby reducing the time and energy required for secondary battery activation and the number of chargers and dischargers required. This can improve secondary battery productivity and reduce manufacturing costs.

[0097] In addition, since the discharge process (S530) includes multiple voltage cutoff processes (S534), unlike the conventional process of fully discharging and then charging, the voltage distribution of multiple secondary batteries can be effectively reduced even when discharged. Accordingly, the uniformity of the secondary batteries is improved, and low-voltage defects can be easily identified.

[0098] In addition, since the discharge speed is higher when the voltage cut-off process (S534) is performed first, the total required time can be reduced even if the voltage cut-off process (S534) is performed multiple times.

[0099] Additionally, the later the voltage cutoff process (S534) is performed, the lower the discharge rate, reducing the influence of the internal resistance of the secondary battery (e.g., heat generation), thereby enabling constant and stable discharge. Consequently, the accuracy of the cutoff voltage is improved, and the cutoff voltage state is stably maintained, effectively reducing voltage dispersion among multiple secondary batteries.

[0100] According to embodiments of the present invention, a secondary battery activation and capacity calculation system (10) may include a charging unit (100) that charges a secondary battery; an aging unit (200) that ages the secondary battery; a discharge unit (300) that discharges (C1 or C2) the secondary battery in a capacity cut-off manner or a voltage cut-off manner; and a capacity calculation unit (400) that calculates a process capacity (QP) of the secondary battery using discharge information that includes an end voltage (VE) that is a voltage of the secondary battery obtained at or after the capacity cut-off in the case of a first discharge (C1) in the capacity cut-off manner, or a discharge capacity (QD) of the secondary battery during the discharge in the case of a second discharge (C2) in the voltage cut-off manner.

[0101] Accordingly, the secondary battery activation method can be simplified from the conventional full discharge followed by a pre-charge to a pre-discharge, thereby reducing the time and energy required for secondary battery activation and the number of chargers and dischargers required. This can improve secondary battery productivity and reduce manufacturing costs.

[0102] In addition, since the discharge unit (300) can perform a second discharge (C2) using a voltage cutoff method, unlike the conventional method of performing a discharge charge after a full discharge, the voltage distribution of multiple secondary batteries can be reduced even when discharged. Accordingly, the uniformity of the secondary batteries is improved, and low-voltage defects can be easily sorted out.

[0103] In addition, since the process capacity (QP) of the secondary battery can be calculated using the end voltage (VE) or discharge capacity (QD) obtained by the discharge (C1 or C2) of the capacity or voltage cutoff method, even if the actual capacities (QAs) of multiple secondary batteries are different, the process capacity (QP) of each secondary battery can have a high correlation with or be similar to the actual capacity (QA). This may be because the difference in the actual capacities (QAs) of multiple secondary batteries is reflected in the end voltage (VE) or discharge capacity (QD). Accordingly, unlike the conventional full discharge, even if the discharge is performed only up to the shipping SOC (i.e., shipping discharge), the reliability of the process capacity (QP) of the secondary battery can be improved.

[0104] According to embodiments of the present invention, the discharge unit (300) can perform the second discharge (C2) in the voltage cut-off manner.

[0105] Accordingly, the voltage distribution of multiple secondary batteries is reduced, the uniformity of the secondary batteries is improved, and low-voltage defects can be easily selected.

[0106] According to embodiments of the present invention, the discharge unit (300) can discharge (C1, C2) using the capacity cutoff method and the voltage cutoff method. The capacity calculation unit (400) can calculate the process capacity (QP) using the discharge information including the end voltage (VE) and the discharge capacity (QD).

[0107] Accordingly, since the process capacity (QP) of the secondary battery is calculated using the end voltage (VE) and discharge capacity (QD) obtained by the discharge (C1, C2) of the capacity and voltage cutoff method, the calculated process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA) of the secondary battery.

[0108] According to embodiments of the present invention, the discharge unit (300) may perform the first discharge (C1) m times (m is a natural number greater than or equal to 2) using the capacity cutoff method or the second discharge (C2) n times (n is a natural number greater than or equal to 2) using the voltage cutoff method. The capacity calculation unit (400) may calculate the process capacity (QP) using the discharge information including at least a portion of the m termination voltages (VE) obtained through the m first discharges (C1) or including at least a portion of the n discharge capacities (QD) obtained through the n second discharges (C2).

[0109] Accordingly, since the second discharge (C2) using the voltage cutoff method can be performed multiple times, the voltage distribution of multiple secondary batteries can be effectively reduced. In addition, since the process capacity (QP) can be calculated using multiple end voltages (VE) or multiple discharge capacities (QD), the process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA).

[0110] According to embodiments of the present invention, m may be 2 or n may be 3.

[0111] Accordingly, since m can be 2, the process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA), while at the same time reducing the time required for secondary battery activation. Furthermore, since n can be 3, the process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA), and the voltage distribution of multiple secondary batteries can be further reduced, while at the same time reducing the time required for secondary battery activation.

[0112] According to embodiments of the present invention, in the m first discharges (C1), the discharge speed of the i-th first discharge (C1) (i is a natural number greater than or equal to 1 and less than m) may be greater than the discharge speed of the i+1-th first discharge (C1), or in the n-th second discharges (C2), the discharge speed of the j-th second discharge (C2) (j is a natural number greater than or equal to 1 and less than n) may be greater than the discharge speed of the j+1-th second discharge (C2).

[0113] Accordingly, the discharge speed increases when the discharge (C1 or C2) is performed first, so even if the discharge (C1 or C2) is performed multiple times, the total required time can be reduced.

[0114] In addition, since the discharge (C1 or C2) is performed later, the discharge speed is lower, so the influence of the internal resistance of the secondary battery (e.g., heat generation, etc.) is reduced, so the discharge can be performed consistently and stably. Accordingly, the accuracy of the cut-off capacity or voltage is improved, and the cut-off state is stably maintained, so that the process capacity (QP) has a high correlation with or is similar to the actual capacity (QA), and the voltage distribution of multiple secondary batteries can be effectively reduced.

[0115] According to embodiments of the present invention, the discharge unit (300) can discharge (C1, C2) in the capacity cut-off manner and the voltage cut-off manner. The first discharge (C1) can be performed before the second discharge (C2).

[0116] Accordingly, even if the first discharge (C1) using the capacity cut-off method is performed, the voltage distribution of multiple secondary batteries can be effectively reduced through the second discharge (C2) using the voltage cut-off method performed later.

[0117] According to embodiments of the present invention, the discharge speed of the capacity cut-off method may be greater than the discharge speed of the voltage cut-off method.

[0118] Accordingly, since the discharge speed of the capacity cutoff method is large, the total required time can be reduced even if the discharge (C1, C2) of the capacity and voltage cutoff methods is performed.

[0119] In addition, since the discharge rate of the voltage cutoff method is low, the influence of the internal resistance of the secondary battery (e.g., heat generation) is reduced, so the accuracy of the cutoff voltage is improved and the cutoff voltage can be stably maintained. Accordingly, the voltage distribution of multiple secondary batteries can be effectively reduced.

[0120] According to embodiments of the present invention, the capacity calculation unit (400) can calculate the process capacity (QP) by applying the shipment discharge information to a correlation function. The correlation function can be derived by regression analysis of the shipment discharge information and actual capacity for a plurality of secondary batteries.

[0121] Accordingly, the process capacity (QP) can be calculated as an appropriate value that is highly correlated with or similar to the actual capacity (QA).

[0122] According to embodiments of the present invention, an activation system for a secondary battery may include a charging unit (100) for charging a secondary battery; an aging unit (200) for aging the secondary battery; and a discharge unit (300) for performing a second discharge (C2) on the secondary battery n times (n is a natural number greater than or equal to 2) in a voltage cutoff manner. In the n times of the second discharge (C2), a discharge rate of the jth (j is a natural number greater than or equal to 1 and less than n) second discharge (C2) may be greater than a discharge rate of the (j+1)th second discharge (C2).

[0123] Accordingly, the secondary battery activation method can be simplified from the conventional full discharge followed by a pre-charge to a pre-discharge, thereby reducing the time and energy required for secondary battery activation and the number of chargers and dischargers required. This can improve secondary battery productivity and reduce manufacturing costs.

[0124] In addition, since the discharge unit (300) can discharge multiple times in a voltage cutoff manner, unlike the conventional method of fully discharging and then charging, the voltage distribution of multiple secondary batteries can be effectively reduced even when discharged. Accordingly, the uniformity of the secondary batteries is improved, and low-voltage defects can be easily sorted out.

[0125] In addition, since the discharge speed is faster when the second discharge (C2) of the voltage cutoff method is performed first, the total required time can be reduced even if the second discharge (C2) of the voltage cutoff method is performed multiple times.

[0126] Additionally, the later the second discharge (C2) using the voltage cutoff method is performed, the lower the discharge rate, reducing the influence of the internal resistance of the secondary battery (e.g., heat generation), allowing for constant and stable discharge. Consequently, the accuracy of the cutoff voltage is improved, and the cutoff voltage state is stably maintained, effectively reducing voltage dispersion among multiple secondary batteries.

[0127] In addition to the effects described above, specific effects of the present invention are described below while explaining specific details for carrying out the invention.

[0128] Figure 1 is a flowchart of a method for activating and calculating capacity of a secondary battery according to one embodiment of the present invention.

[0129] FIG. 2 is a schematic diagram illustrating an example of a change in voltage over time of a secondary battery discharged by the method of FIG. 1.

[0130] FIG. 3 is a schematic diagram illustrating one example of a change in discharge current over time when a secondary battery is discharged using the method of FIG. 1.

[0131] FIG. 4 is a schematic diagram illustrating one example of voltage changes over time for three secondary batteries discharged by the method of FIG. 1.

[0132] Fig. 5 is a diagram showing the voltage distribution of multiple secondary batteries activated by the method of Fig. 1.

[0133] Figure 6 is a table showing the correlation between the process capacity of a secondary battery calculated using the capacity calculation method of Figure 1 and the actual capacity of the secondary battery.

[0134] Figure 7 is a block diagram of a secondary battery activation and capacity calculation system according to one embodiment of the present invention.

[0135] [Explanation of symbols]

[0136] 10: Secondary battery activation and capacity calculation system

[0137] 100: Charging section 200: Aging section

[0138] 300: Shipment discharge section 400: Capacity calculation section

[0139] S500: Method for activating and calculating the capacity of a secondary battery

[0140] S510: Charging process S520: Aging process

[0141] S530: Shipment discharge process S540: Capacity calculation process

[0142] S532: Capacity cutoff process S534: Voltage cutoff process

[0143] C1: Discharge using capacity cutoff C2: Discharge using voltage cutoff

[0144] VE: End voltage QD: Discharge capacity

[0145] QP: Process Capacity QA: Actual Capacity

[0146] The above-described objects, features, and advantages will be described in detail below with reference to the accompanying drawings, so that those skilled in the art can easily practice the technical idea of ​​the present invention. In describing the present invention, if it is determined that a detailed description of known technologies related to the present invention may unnecessarily obscure the gist of the present invention, a detailed description thereof will be omitted. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

[0147] Although terms like "first" and "second" are used to describe various components, these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless otherwise specified, a "first" component may also be a "second" component.

[0148] Throughout the specification, unless otherwise specifically stated, each element may be singular or plural.

[0149] Hereinafter, the phrase "any configuration is placed on (or below)" a component or "on (or below)" a component may mean that any configuration is placed in contact with the upper surface (or lower surface) of said component, and that other configurations may be interposed between said component and any configuration placed on (or below) said component.

[0150] Additionally, when it is described that a component is "connected," "coupled," or "connected" to another component, it should be understood that the components may be directly connected or connected to one another, but that other components may also be "interposed" between the components, or that each component may be "connected," "coupled," or "connected" through another component.

[0151] As used herein, singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as "consisting of" or "comprising" should not necessarily be construed to include all of the components or steps described in the specification, and should be construed to mean that some of the components or steps may not be included, or that additional components or steps may be included.

[0152]

[0153] FIG. 1 is a flowchart of a method for activating and calculating a capacity of a secondary battery according to an embodiment of the present invention. FIG. 2 is a diagram schematically illustrating an example of a change in voltage over time of a secondary battery discharged by the method of FIG. 1. FIG. 3 is a diagram schematically illustrating an example of a change in discharge current over time when a secondary battery is discharged by the method of FIG. 1. FIG. 4 is a diagram schematically illustrating an example of a change in voltage over time of three secondary batteries discharged by the method of FIG. 1. FIG. 5 is a diagram illustrating voltage distributions of a plurality of secondary batteries activated by the method of FIG. 1. FIG. 6 is a table illustrating a correlation between a process capacity of a secondary battery calculated by the capacity calculation method of FIG. 1 and an actual capacity of the secondary battery. FIG. 7 is a block diagram of a secondary battery activation and capacity calculation system according to an embodiment of the present invention.

[0154]

[0155] [Secondary battery activation and capacity calculation method]

[0156] Referring to FIG. 1, a method (S500) for activating and calculating capacity of a secondary battery according to one embodiment may include a charging process (S510), an aging process (S520), a shipping discharge process (S530), and a capacity calculation process (S540).

[0157] The secondary battery can be charged during the charging process (S510). For example, the secondary battery can be charged (e.g., fully charged) to the voltage P1 of FIG. 2 during the charging process (S510). The charging process (S510) can be performed more than once.

[0158] In the aging process (S520), the secondary battery may be aged. The aging process (S520) may be performed more than once. The aging process (S520) may be performed between the charging process (S510) and the discharge process (S530) or between the charging process (S510) and the discharge process (S530). In the aging process (S520), the secondary battery may be placed in an environment having a predetermined temperature and / or pressure.

[0159] The discharge process (S530) may be performed after the charging process (S510) and the aging process (S520). The discharge process (S530) may be the last process performed in the activation method. For example, in the discharge process (S530), the secondary battery may be discharged to a voltage of P2 in FIG. 2 or a capacity corresponding to the voltage of P2 in FIG. 2. The discharge process (S530) may include a capacity cutoff process (S532) or a voltage cutoff process (S534).

[0160] In the capacity cut-off process (S532), the secondary battery can be discharged for the first time (C1) in a capacity cut-off manner (Figs. 2 to 4). Specifically, when the secondary battery is discharged to a predetermined capacity (e.g., 15000 mAh or 60% to 70%), the discharge can be stopped. In the capacity cut-off process (S532), the end voltage (VE), which is the voltage of the secondary battery at or after the capacity cut-off, can be obtained (Fig. 2). That is, in the capacity cut-off process (S532), the end voltage (VE), which is the voltage of the secondary battery after the first discharge (C1) in the capacity cut-off manner, can be obtained.

[0161] In the voltage cutoff process (S534), the secondary battery can be subjected to a second discharge (C2) using the voltage cutoff method (Figs. 2 to 4). Specifically, when the secondary battery reaches a predetermined voltage (e.g., 3.5 V or the voltage of P2 in Fig. 2), the discharge can be stopped. In the voltage cutoff process (S534), the discharge capacity (QD) of the secondary battery during the second discharge (C2) using the voltage cutoff method can be obtained (Fig. 3).

[0162] In the capacity calculation process (S540), the process capacity (QP) of the secondary battery can be calculated using the discharge information. Here, the discharge information may include an end voltage (VE) or a discharge capacity (QD). The end voltage (VE) may be a voltage of the secondary battery obtained at the time of or after the capacity cut-off of the capacity cut-off process (S532). The discharge capacity (QD) may be a capacity discharged from the secondary battery during the voltage cut-off process (S534). The process capacity (QP) may mean an estimated value of the capacity of a fully charged secondary battery.

[0163] For example, in the capacity calculation process (S540), the process capacity (QP) can be calculated by applying the above-mentioned discharge information to the correlation function. Here, the correlation function can be derived by regression analysis of the above-mentioned discharge information and the actual capacity (QA) for a plurality of secondary batteries. The actual capacity (QA) may be the actual total capacity of the secondary battery. For example, the actual capacity (QA) may be measured by fully discharging a fully charged secondary battery at a low current. The actual capacity (QA) may be the fully discharged capacity of the secondary battery at a specific temperature (e.g., 40 degrees Celsius). Regression analysis is one of the data analysis methods used in statistics, and may be a statistical analysis method that assumes a mathematical model to identify a functional relationship between variables and estimates this model from data of measured variables.

[0164] Accordingly, the process capacity (QP) can be calculated as an appropriate value that is highly correlated with or similar to the actual capacity (QA) (Fig. 6).

[0165]

[0166] In this way, the method for activating and calculating the capacity of a secondary battery (S500) may include a charging process (S510), an aging process (S520), a shipping discharge process (S530), and a capacity calculation process (S540). Accordingly, the method for activating a secondary battery is simplified from the conventional full discharge followed by shipping charge to shipping discharge, thereby reducing the time and energy required for activating the secondary battery and reducing the number of chargers and dischargers. As a result, the productivity of the secondary battery can be improved and the manufacturing cost can be reduced.

[0167] Here, shipping charge and shipping discharge may be methods for setting the shipping SOC of a secondary battery. Shipping charge may be a method of discharging (e.g., fully discharging) a charged (e.g., fully charged) secondary battery and then charging it to the shipping SOC, and shipping discharge may be a method of discharging a charged (e.g., fully charged) secondary battery to the shipping SOC (e.g., 30% to 40%).

[0168] In addition, since the discharge process (S530) can include a voltage cutoff process (S534), the voltage distribution of multiple secondary batteries can be reduced even when discharged, unlike the conventional method of fully discharging and then charging, (dotted circle area in Fig. 4, Fig. 5). Accordingly, the uniformity of the secondary batteries is improved, and low-voltage defects can be easily sorted out.

[0169] Here, a low-voltage defect may be a defect in which the second voltage decreases significantly compared to the first voltage after a predetermined period of time due to abnormal leakage current flowing within the secondary battery. If the voltage distribution is reduced, there is no need to individually measure or adjust the first voltages of multiple secondary batteries to identify low-voltage defects. In other words, low-voltage defect identification is possible by individually measuring only the second voltages of multiple secondary batteries.

[0170] In addition, since the process capacity (QP) of the secondary battery can be calculated using the end voltage (VE) or discharge capacity (QD) obtained by the capacity or voltage cut-off process (S532, S534), even if the actual capacities (QAs) of multiple secondary batteries are different, the process capacity (QP) of each secondary battery can have a high correlation with or be similar to the actual capacity (QA) (Fig. 6). This may be because the difference in the actual capacities (QAs) of multiple secondary batteries is reflected in the end voltage (VE) or discharge capacity (QD) of the cut-off process (S532, S534). Accordingly, unlike the conventional full discharge, even if the discharge is performed only up to the shipping SOC (i.e., shipping discharge), the reliability of the process capacity (QP) of the secondary battery can be improved.

[0171]

[0172] Meanwhile, the discharge process (S530) may include a voltage cutoff process (S534) (Figs. 1 to 4).

[0173] Accordingly, the voltage distribution of multiple secondary batteries is reduced, the uniformity of the secondary batteries is improved, and low-voltage defects can be easily selected (dotted circle portion of Fig. 4, Fig. 5).

[0174] The discharge process (S530) may include a capacity cutoff process (S532) and a voltage cutoff process (S534) (Figs. 1 to 4). At this time, in the capacity calculation process (S540), the process capacity (QP) may be calculated using the discharge information including the end voltage (VE) and discharge capacity (QD) (Fig. 6).

[0175] Accordingly, since the process capacity (QP) of the secondary battery is calculated using the end voltage (VE) and discharge capacity (QD) obtained through the capacity and voltage cutoff process (S532, S534), the calculated process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA) of the secondary battery (Fig. 6).

[0176] The capacity cut-off process (S532) may be performed m times (m is a natural number greater than or equal to 2) or the voltage cut-off process (S534) may be performed n times (n is a natural number greater than or equal to 2) (Figs. 1 to 4). For example, as shown in Figs. 2 to 4, the first discharge (C1) of the capacity cut-off method may be performed twice and the second discharge (C2) of the voltage cut-off method may be performed three times. When the capacity cut-off process (S532) is performed m times, the cut-off capacity may be the same or different for each cycle.

[0177] At this time, in the capacity calculation process (S540), the process capacity (QP) can be calculated using the shipment discharge information that includes at least some of the m termination voltages (VE) obtained through the m capacity cutoff processes (S532) or at least some of the n discharge capacities (QD) obtained through the n voltage cutoff processes (S534).

[0178] Accordingly, since the voltage cut-off process (S534) can be performed multiple times, the voltage distribution of multiple secondary batteries can be effectively reduced (dotted circle portion in FIG. 4, FIG. 5). In addition, since the process capacity (QP) can be calculated using multiple end voltages (VE) or multiple discharge capacities (QD), the process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA) (FIG. 6).

[0179] At this time, m may be 2 or n may be 3 (Figs. 2 to 4).

[0180] Accordingly, since m can be 2, the process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA), while at the same time reducing the time required for secondary battery activation. Furthermore, since n can be 3, the process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA), and the voltage distribution of multiple secondary batteries can be further reduced, while at the same time reducing the time required for secondary battery activation.

[0181] In the m-th capacity cut-off process (S532), the discharge speed of the secondary battery in the i-th capacity cut-off process (S532) (i is a natural number greater than or equal to 1 and less than m) may be greater than the discharge speed of the secondary battery in the i+1-th capacity cut-off process (S532). Alternatively, in the n-th voltage cut-off process (S534), the discharge speed of the secondary battery in the j-th voltage cut-off process (S534) (j is a natural number greater than or equal to 1 and less than n) may be greater than the discharge speed of the secondary battery in the j+1-th voltage cut-off process (S534).

[0182] For example, in the first discharge (C1) of the two capacity cutoff methods as shown in Fig. 3, the discharge current amount (discharge rate) of each first discharge (C1) can gradually decrease sequentially. In addition, in the second discharge (C2) of the three voltage cutoff methods as shown in Fig. 3, the discharge current amount of each second discharge (C2) can gradually decrease sequentially.

[0183] Accordingly, the discharge speed increases as the cut-off process is performed first, so even if the capacity or voltage cut-off process (S532 or S534) is performed multiple times, the total required time can be reduced.

[0184] In addition, the later the cut-off process is performed, the lower the discharge rate, which reduces the influence of the internal resistance of the secondary battery (e.g., heat generation), so that the discharge can be performed consistently and stably. Accordingly, the accuracy of the cut-off capacity or voltage is improved, and the cut-off state is stably maintained, so that the process capacity (QP) has a high correlation with or is similar to the actual capacity (QA), and the voltage dispersion of multiple secondary batteries can be effectively reduced.

[0185] In the case where the discharge process (S530) includes a capacity cut-off process (S532) and a voltage cut-off process (S534), the capacity cut-off process (S532) may be performed before the voltage cut-off process (S534) (Figs. 1 to 4). For example, as shown in Figs. 2 to 4, the first discharge (C1) of the capacity cut-off method may be performed before the second discharge (C2) of the voltage cut-off method.

[0186] Accordingly, even if the capacity cut-off process (S532) is performed, the voltage distribution of multiple secondary batteries can be effectively reduced through the voltage cut-off process (S534) performed later.

[0187] The discharge speed of the secondary battery in the capacity cut-off process (S532) may be greater than the discharge speed of the secondary battery in the voltage cut-off process (S534) (Fig. 3).

[0188] Accordingly, since the discharge speed of the capacity cut-off process (S532) is large, the total required time can be reduced even if the capacity and voltage cut-off processes (S532, S534) are performed.

[0189] In addition, since the discharge speed of the voltage cut-off process (S534) is low, the influence of the internal resistance of the secondary battery (e.g., heat generation, etc.) is reduced, so the accuracy of the cut-off voltage is improved and the cut-off voltage can be stably maintained. Accordingly, the voltage distribution of multiple secondary batteries can be effectively reduced.

[0190]

[0191] Referring to Fig. 5, it can be confirmed that 262 secondary batteries activated by the secondary battery activation and capacity calculation method (S500) have a very small voltage distribution with a standard deviation of 1.819 mV.

[0192] Referring to Fig. 6, it can be confirmed that the correlation between the process capacity (QP) and the actual capacity (QA) of 63 secondary batteries activated by the method for activating and calculating the capacity of a secondary battery (S500) and calculating the process capacity (QP) is very high, with an R^2 value of 93.8%. This is because the process capacity (QP) of the 63 secondary batteries was calculated using the derived correlation function after deriving the correlation function by performing multiple regression analysis on values ​​including five values ​​of two end voltages (VE, Fig. 2) and three discharge capacities (QD, Fig. 3).

[0193]

[0194] [Method of activating secondary batteries]

[0195] The method for activating a secondary battery according to one embodiment of the present invention may include a charging process (S510), an aging process (S520), and a shipment discharge process (S530), similar to the method for activating and calculating capacity of a secondary battery (S500) described above. The capacity calculation process (S540) described above may be omitted. Hereinafter, the differences from the method for activating and calculating capacity of a secondary battery described above (S500) will be examined.

[0196] The discharge process (S530) may include a voltage cutoff process (S534).

[0197] In the voltage cut-off process (S534), the secondary battery can be discharged a second time (C2) in a voltage cut-off manner. The voltage cut-off process (S534) can be performed n times (n is a natural number greater than or equal to 2). In the n voltage cut-off processes (S534), the discharge speed of the secondary battery in the jth voltage cut-off process (S534) (j is a natural number greater than or equal to 1 and less than n) can be greater than the discharge speed of the secondary battery in the j+1th voltage cut-off process (S534).

[0198] Accordingly, the secondary battery activation method can be simplified from the conventional full discharge followed by a pre-charge to a pre-discharge, thereby reducing the time and energy required for secondary battery activation and the number of chargers and dischargers required. This can improve secondary battery productivity and reduce manufacturing costs.

[0199] In addition, since the discharge process (S530) includes multiple voltage cutoff processes (S534), unlike the conventional process of fully discharging and then charging, the voltage distribution of multiple secondary batteries can be effectively reduced even when discharged. Accordingly, the uniformity of the secondary batteries is improved, and low-voltage defects can be easily identified.

[0200] In addition, since the discharge speed is higher when the voltage cut-off process (S534) is performed first, the total required time can be reduced even if the voltage cut-off process (S534) is performed multiple times.

[0201] Additionally, the later the voltage cutoff process (S534) is performed, the lower the discharge rate, reducing the influence of the internal resistance of the secondary battery (e.g., heat generation), thereby enabling constant and stable discharge. Consequently, the accuracy of the cutoff voltage is improved, and the cutoff voltage state is stably maintained, effectively reducing voltage dispersion among multiple secondary batteries.

[0202] Matters not mentioned regarding the method of activating a secondary battery can be inferred from the method of activating and calculating capacity of a secondary battery (S500) described above.

[0203]

[0204] [Secondary Battery Activation and Capacity Calculation System]

[0205] Referring to FIG. 7, a secondary battery activation and capacity calculation system (10) according to one embodiment of the present invention may include a charging unit (100), an aging unit (200), a discharge unit (300), and a capacity calculation unit (400).

[0206] The charging unit (100) can charge a secondary battery. For example, the charging unit (100) can charge (e.g., fully charge) a secondary battery up to the voltage P1 of FIG. 2. Charging can be performed more than once.

[0207] The aging unit (200) can age the secondary battery. The aging unit (200) can provide the secondary battery with an environment having a predetermined temperature and / or pressure. The aging can be performed more than once. The aging can be performed between charging of the charging unit (100) or between charging of the charging unit (100) and discharging of the discharge / shipping unit (300).

[0208] The discharge unit (300) can discharge the secondary battery to the discharge SOC. For example, the discharge unit (300) can discharge the secondary battery to the voltage of P2 of FIG. 2 or to a capacity corresponding to the voltage of P2. The discharge unit (300) can discharge the secondary battery (C1 or C2) using a capacity cut-off method or a voltage cut-off method (FIGS. 2 to 4).

[0209] The first discharge (C1) of the capacity cut-off method may be a method of stopping the discharge when the secondary battery is discharged to a predetermined capacity (e.g., 15,000 mAh or 60% to 70%). When the discharge unit (300) discharges the secondary battery in the first discharge (C1) of the capacity cut-off method, the discharge unit (300) can obtain the end voltage (VE), which is the voltage of the secondary battery, at or after the capacity cut-off (Fig. 2).

[0210] The first discharge (C1) using the voltage cutoff method may be a method of stopping the discharge when the secondary battery reaches a predetermined voltage (e.g., 3.5 V or the voltage of P2 in FIG. 2). When the discharge unit (300) discharges the secondary battery the second time (C2) using the voltage cutoff method, the discharge unit (300) can obtain the discharge capacity (QD) of the secondary battery during the discharge (FIG. 3).

[0211] The capacity calculation unit (400) can calculate the process capacity (QP) of a secondary battery using the discharge information including the end voltage (VE) or the discharge capacity (QD). The process capacity (QP) can mean an estimated value of the capacity of a fully charged secondary battery.

[0212] For example, the capacity calculation unit (400) can calculate the process capacity (QP) by applying the above-mentioned discharge information to the correlation function. Here, the correlation function can be derived by regression analysis of the above-mentioned discharge information and the actual capacity for a plurality of secondary batteries. The actual capacity (QA) can be the actual total capacity of the secondary battery. For example, the actual capacity (QA) can be measured by fully discharging a fully charged secondary battery at a low current. The actual capacity (QA) can be the fully discharged capacity of the secondary battery at a specific temperature (e.g., 40 degrees Celsius).

[0213] Accordingly, the process capacity (QP) can be calculated as an appropriate value that is highly correlated with or similar to the actual capacity (QA).

[0214]

[0215] In this way, the secondary battery activation and capacity calculation system (10) may include a charging unit (100), an aging unit (200), a discharge unit (300), and a capacity calculation unit (400). Accordingly, the secondary battery activation method can be simplified from the conventional discharge-then-discharge-then-discharge method to discharge-then-discharge method, thereby reducing the time and energy required for secondary battery activation and reducing the number of chargers and dischargers. Accordingly, the productivity of the secondary battery can be improved and the manufacturing cost can be reduced.

[0216] In addition, since the discharge unit (300) can perform a second discharge (C2) using a voltage cutoff method, unlike the conventional method of performing a discharge charge after a full discharge, the voltage distribution of multiple secondary batteries can be reduced even when discharged. Accordingly, the uniformity of the secondary batteries is improved, and low-voltage defects can be easily sorted out.

[0217] In addition, since the process capacity (QP) of the secondary battery can be calculated using the end voltage (VE) or discharge capacity (QD) obtained by the discharge (C1 or C2) of the capacity or voltage cutoff method, even if the actual capacities (QAs) of multiple secondary batteries are different, the process capacity (QP) of each secondary battery can have a high correlation with or be similar to the actual capacity (QA). This may be because the difference in the actual capacities (QAs) of multiple secondary batteries is reflected in the end voltage (VE) or discharge capacity (QD). Accordingly, unlike the conventional full discharge, even if the discharge is performed only up to the shipping SOC (i.e., shipping discharge), the reliability of the process capacity (QP) of the secondary battery can be improved.

[0218]

[0219] Meanwhile, the discharge unit (300) can perform the second discharge (C2) using the voltage cut-off method (Figs. 1 to 4).

[0220] Accordingly, the voltage distribution of multiple secondary batteries is reduced, the uniformity of the secondary batteries is improved, and low-voltage defects can be easily selected.

[0221] The discharge unit (300) can discharge (C1, C2) in a capacity and voltage cutoff manner (Figs. 1 to 4). At this time, the capacity calculation unit (400) can calculate the process capacity (QP) using the discharge information including the termination voltage (VE) and discharge capacity (QD) (Fig. 6).

[0222] Accordingly, since the process capacity (QP) of the secondary battery is calculated using the end voltage (VE) and discharge capacity (QD) obtained by the discharge (C1, C2) of the capacity and voltage cutoff method, the calculated process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA) of the secondary battery.

[0223] The discharge unit (300) can perform the first discharge (C1) m times (m is a natural number greater than or equal to 2) in a capacity cutoff manner or the second discharge (C2) n times (n is a natural number greater than or equal to 2) in a voltage cutoff manner (Figs. 1 to 4).

[0224] The capacity calculation unit (400) can calculate the process capacity (QP) using the discharge information including at least some of the m termination voltages (VE) obtained through the m first discharges (C1) or at least some of the n discharge capacities (QD) obtained through the n second discharges (C2).

[0225] Accordingly, since the second discharge (C2) using the voltage cutoff method can be performed multiple times, the voltage distribution of multiple secondary batteries can be effectively reduced. In addition, since the process capacity (QP) can be calculated using multiple end voltages (VE) or multiple discharge capacities (QD), the process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA).

[0226] m may be 2 or the above n may be 3 (Figs. 2 to 4).

[0227] Accordingly, since m can be 2, the process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA), while at the same time reducing the time required for secondary battery activation. Furthermore, since n can be 3, the process capacity (QP) can have a higher correlation with or be more similar to the actual capacity (QA), and the voltage distribution of multiple secondary batteries can be further reduced, while at the same time reducing the time required for secondary battery activation.

[0228] In the m-th first discharge (C1), the discharge speed of the i-th first discharge (C1) (where i is a natural number greater than or equal to 1 and less than m) may be greater than the discharge speed of the (i+1)th first discharge (C1) (Fig. 3). Alternatively, in the n-th second discharge (C2), the discharge speed of the j-th second discharge (C2) (where j is a natural number greater than or equal to 1 and less than n) may be greater than the discharge speed of the j+1-th second discharge (C2) (Fig. 3).

[0229] Accordingly, the discharge speed increases when the discharge (C1 or C2) is performed first, so even if the discharge (C1 or C2) is performed multiple times, the total required time can be reduced.

[0230] In addition, since the discharge (C1 or C2) is performed later, the discharge speed is lower, so the influence of the internal resistance of the secondary battery (e.g., heat generation, etc.) is reduced, so the discharge can be performed consistently and stably. Accordingly, the accuracy of the cut-off capacity or voltage is improved, and the cut-off state is stably maintained, so that the process capacity (QP) has a high correlation with or is similar to the actual capacity (QA), and the voltage distribution of multiple secondary batteries can be effectively reduced.

[0231] When the discharge unit (300) discharges (C1, C2) in a capacity and voltage cutoff manner, the first discharge (C1) can be performed before the second discharge (C2) (Figs. 1 to 4).

[0232] Accordingly, even if the first discharge (C1) using the capacity cut-off method is performed, the voltage distribution of multiple secondary batteries can be effectively reduced through the second discharge (C2) using the voltage cut-off method performed later.

[0233] The discharge rate of the capacity cut-off method can be greater than the discharge rate of the voltage cut-off method (Fig. 3).

[0234] Accordingly, since the discharge speed of the capacity cutoff method is large, the total required time can be reduced even if the discharge (C1, C2) of the capacity and voltage cutoff methods is performed.

[0235] In addition, since the discharge rate of the voltage cutoff method is low, the influence of the internal resistance of the secondary battery (e.g., heat generation) is reduced, so the accuracy of the cutoff voltage is improved and the cutoff voltage can be stably maintained. Accordingly, the voltage distribution of multiple secondary batteries can be effectively reduced.

[0236]

[0237] Matters not mentioned about the secondary battery activation and capacity calculation system (10) can be inferred from the secondary battery activation and capacity calculation method (S500) described above.

[0238]

[0239] [Secondary battery activation system]

[0240] The secondary battery activation system according to one embodiment of the present invention may include a charging unit (100), an aging unit (200), and a discharge unit (300), similar to the secondary battery activation and capacity calculation system (10) described above. The capacity calculation unit (400) described above may be omitted. Hereinafter, the differences from the secondary battery activation and capacity calculation system (10) described above will be examined.

[0241] The discharge unit (300) can perform a second discharge (C2) of the secondary battery n times (n is a natural number greater than or equal to 2) in a voltage cutoff manner. In the n times of the second discharge (C2), the discharge speed of the jth (j is a natural number greater than or equal to 1 and less than n)th second discharge (C2) can be greater than the discharge speed of the (j+1)th second discharge (C2).

[0242] Accordingly, the secondary battery activation method can be simplified from the conventional full discharge followed by a pre-charge to a pre-discharge, thereby reducing the time and energy required for secondary battery activation and the number of chargers and dischargers required. This can improve secondary battery productivity and reduce manufacturing costs.

[0243] In addition, since the discharge unit (300) can discharge multiple times in a voltage cutoff manner, unlike the conventional method of fully discharging and then charging, the voltage distribution of multiple secondary batteries can be effectively reduced even when discharged. Accordingly, the uniformity of the secondary batteries is improved, and low-voltage defects can be easily sorted out.

[0244] In addition, since the discharge speed is faster when the second discharge (C2) of the voltage cutoff method is performed first, the total required time can be reduced even if the second discharge (C2) of the voltage cutoff method is performed multiple times.

[0245] Additionally, the later the second discharge (C2) using the voltage cutoff method is performed, the lower the discharge rate, reducing the influence of the internal resistance of the secondary battery (e.g., heat generation), allowing for constant and stable discharge. Consequently, the accuracy of the cutoff voltage is improved, and the cutoff voltage state is stably maintained, effectively reducing voltage dispersion among multiple secondary batteries.

[0246] Matters not mentioned about the activation system of the secondary battery can be inferred from the activation and capacity calculation system (10) of the secondary battery described above.

[0247]

[0248] It should be understood that the above-described embodiments are illustrative in all respects and not restrictive, and the scope of the present invention will be determined by the claims that follow rather than by the detailed description set forth above. Furthermore, the meaning and scope of the claims that follow, as well as all variations and modifications derived from their equivalent concepts, should be construed as encompassing the scope of the present invention.

[0249] Although the present invention has been described with reference to the drawings exemplified above, it is to be understood that the present invention is not limited to the embodiments and drawings disclosed herein, and that various modifications may be made by those skilled in the art within the scope of the technical idea of ​​the present invention. Furthermore, even if the operational effects according to the configuration of the present invention have not been explicitly described while describing the embodiments of the present invention, it is natural that the effects predictable by the corresponding configuration should also be acknowledged.

Claims

1. Charging process for charging a secondary battery (S510); Aging process (S520) for aging the secondary battery; A shipping discharge process (S530) that is performed after the charging process (S510) and the aging process (S520) and includes a capacity cut-off process (S532) for first discharging (C1) the secondary battery in a capacity cut-off manner or a voltage cut-off process (S534) for second discharging (C2) the secondary battery in a voltage cut-off manner; and A capacity calculation process (S540) for calculating the process capacity (QP) of the secondary battery using the discharge information including the end voltage (VE) which is the voltage of the secondary battery obtained at the time of the capacity cut-off of the capacity cut-off process (S532) or after the capacity cut-off or the discharge capacity (QD) of the secondary battery discharged during the voltage cut-off process (S534). Method for activating and calculating the capacity of a secondary battery.

2. In claim 1, The above-mentioned discharge process (S530) is a method for activating and calculating the capacity of the secondary battery, including the voltage cut-off process (S534).

3. In claim 1 or claim 2, The above discharge process (S530) includes the capacity cutoff process (S532) and the voltage cutoff process (S534). A method for activating and calculating capacity of a secondary battery, wherein in the above capacity calculation process (S540), the process capacity (QP) is calculated using the shipment discharge information including the end voltage (VE) and discharge capacity (QD).

4. In any one of claims 1 to 3, The above capacity cut-off process (S532) is performed m times (m is a natural number greater than or equal to 2) or the above voltage cut-off process (S534) is performed n times (n is a natural number greater than or equal to 2). A method for activating and calculating capacity of a secondary battery, wherein, in the capacity calculation process (S540), the process capacity (QP) is calculated using the shipment discharge information that includes at least some of the m termination voltages (VE) obtained through the m capacity cutoff processes (S532) or at least some of the n discharge capacities (QD) obtained through the n voltage cutoff processes (S534).

5. In claim 4, A method for activating and calculating capacity of a secondary battery, wherein the above m is 2 or the above n is 3.

6. In claim 4 or claim 5, In the above m-th capacity cut-off process (S532), the discharge speed of the secondary battery of the i-th capacity cut-off process (S532) (i is a natural number greater than or equal to 1 and less than m) is greater than the discharge speed of the secondary battery of the i+1-th capacity cut-off process (S532), or A method for activating and calculating capacity of a secondary battery, wherein in the nth voltage cut-off process (S534), the discharge speed of the secondary battery in the jth (j is a natural number greater than or equal to 1 and less than n) voltage cut-off process (S534) is greater than the discharge speed of the secondary battery in the j+1th voltage cut-off process (S534).

7. In any one of claims 1 to 6, The above discharge process (S530) includes the capacity cutoff process (S532) and the voltage cutoff process (S534). A method for activating and calculating capacity of a secondary battery, wherein the above capacity cut-off process (S532) is performed before the above voltage cut-off process (S534).

8. In claim 7, A method for activating and calculating capacity of a secondary battery, wherein the discharge speed of the secondary battery in the capacity cut-off process (S532) is greater than the discharge speed of the secondary battery in the voltage cut-off process (S534).

9. In any one of claims 1 to 8, In the above capacity calculation process (S540), the process capacity (QP) is calculated by applying the above shipment discharge information to the correlation function, The above correlation function is a method for activating and calculating the capacity of a secondary battery, which is derived by regression analysis of the shipment discharge information and actual capacity for a plurality of the secondary batteries.

10. Charging process for charging a secondary battery (S510); An aging process (S520) for aging the secondary battery; and It includes a shipping discharge process (S530) that is performed after the above charging process (S510) and aging process (S520), and includes a voltage cut-off process (S534) that performs a second discharge (C2) of the secondary battery in a voltage cut-off manner. The above voltage cutoff process (S534) is performed n times (n is a natural number greater than or equal to 2), In the above n-th voltage cut-off process (S534), the discharge speed of the secondary battery of the j-th voltage cut-off process (S534) (j is a natural number greater than or equal to 1 and less than n) is greater than the discharge speed of the secondary battery of the j+1-th voltage cut-off process (S534). Method of activating a secondary battery.

11. Charging unit (100) for charging a secondary battery; An aging unit (200) for aging the secondary battery; A discharge unit (300) that discharges the secondary battery (C1 or C2) in a capacity cut-off manner or a voltage cut-off manner; and In the case of performing the first discharge (C1) using the capacity cut-off method, the terminal voltage (VE) of the secondary battery obtained at or after the capacity cut-off is included, or in the case of performing the second discharge (C2) using the voltage cut-off method, the discharge capacity (QD) of the secondary battery during the discharge is included, and a capacity calculation unit (400) is included to calculate the process capacity (QP) of the secondary battery. Secondary battery activation and capacity calculation system.

12. In claim 11, The above-mentioned discharge unit (300) is an activation and capacity calculation system of the secondary battery that performs the second discharge (C2) using the voltage cut-off method.

13. In claim 11 or claim 12, The above discharge unit (300) discharges (C1, C2) using the capacity cutoff method and voltage cutoff method, The above capacity calculation unit (400) is an activation and capacity calculation system of the secondary battery that calculates the process capacity (QP) using the discharge information including the termination voltage (VE) and discharge capacity (QD).

14. In any one of claims 11 to 13, The above-mentioned discharge unit (300) performs the first discharge (C1) m times (m is a natural number greater than or equal to 2) using the capacity cut-off method or the second discharge (C2) n times (n is a natural number greater than or equal to 2) using the voltage cut-off method. The above capacity calculation unit (400) calculates the process capacity (QP) using the output discharge information including at least a portion of the m number of termination voltages (VE) obtained through the m number of the first discharges (C1) or including at least a portion of the n number of discharge capacities (QD) obtained through the n number of the second discharges (C2). The above secondary battery activation and capacity calculation system.

15. In claim 14, A secondary battery activation and capacity calculation system, wherein the above m is 2 or the above n is 3.

16. In claim 14 or claim 15, In the above m first discharges (C1), the discharge speed of the i (i is a natural number greater than or equal to 1 and less than m) first discharge (C1) is greater than the discharge speed of the i+1 first discharge (C1), or A secondary battery activation and capacity calculation system, wherein in the above n second discharges (C2), the discharge speed of the jth (j is a natural number greater than or equal to 1 and less than n) second discharge (C2) is greater than the discharge speed of the (j+1)th second discharge (C2).

17. In claim 11, The above discharge unit (300) discharges (C1, C2) using the capacity cutoff method and voltage cutoff method, A secondary battery activation and capacity calculation system, wherein the first discharge (C1) is performed before the second discharge (C2).

18. In claim 17, A secondary battery activation and capacity calculation system, wherein the discharge speed of the above capacity cut-off method is greater than the discharge speed of the above voltage cut-off method.

19. In any one of claims 11 to 18, The above capacity calculation unit (400) calculates the process capacity (QP) by applying the above discharge information to the correlation function. The above correlation function is a secondary battery activation and capacity calculation system derived by regression analysis of the shipment discharge information and actual capacity for a plurality of secondary batteries.

20. Charging unit (100) for charging a secondary battery; An aging unit (200) for aging the secondary battery; and The secondary battery includes a discharge unit (300) that discharges the secondary battery n times (n is a natural number greater than or equal to 2) times in a voltage cutoff manner, In the above n-th second discharge (C2), the discharge speed of the j-th second discharge (C2) (j is a natural number greater than or equal to 1 and less than n) is greater than the discharge speed of the j+1-th second discharge (C2). Activation system of secondary batteries.

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