Battery management system and battery state of health management method therefor

Abstract

Provided is a battery SoH management method for a battery management system, comprising the steps of: checking the SOH of each of a plurality of battery modules included in a battery pack; on the basis of at least some of the respective SoHs of the plurality of battery modules, checking one or more first battery modules, which are at least some of the plurality of battery modules; and rechecking the SoH of the one or more first battery modules by considering at least a portion of the margin capacity of the one or more first battery modules as an available capacity.

Description

Battery management system and method for managing battery health status thereof

[0001] This application claims the benefit of priority to Republic of Korea Patent Application No. 2024-0044649, dated April 2, 2024, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a battery management system and a method for managing the health status of a battery thereof.

[0003] Batteries are typically manufactured in a hierarchical structure of pack-module-cell. Specifically, a battery pack may comprise multiple battery modules, and each battery module may comprise multiple battery cells. In such a battery structure, the state-of-health (SoH) of the battery pack is calculated based on the worst SoH among the battery modules it contains, and similarly, the state-of-health (SoH) of the battery module may be calculated based on the worst SoH among the battery cells it contains. The battery may be managed by a battery management system so that it can be used according to the calculated SoH.

[0004] This SoH calculation method has the advantage of maintaining consistent performance across battery packs or modules, reducing the risk of overload or overcharge, optimizing lifespan, and enabling better performance prediction. However, this method also has its drawbacks. One drawback is that even if a specific battery module ages and is replaced with a new one, the SoH of the entire battery pack is determined by the SoH of the remaining modules, preventing the full performance of the new module from being utilized. Furthermore, if only some battery modules age rapidly, the pack may be used based on the aged module even though the other modules remain healthy, resulting in wasted performance.

[0005] The disclosed embodiments provide a battery management system and a method for managing the battery health status thereof. Specifically, a first object of the present invention is to provide a method for managing battery SoH based on the margin capacity of a battery module or battery cell.

[0006] The technical tasks to be achieved by this embodiment are not limited to the technical tasks described above, and other technical tasks can be inferred from the following embodiments.

[0007] One aspect of the present disclosure provides a method for managing a battery state-of-health (SoH) of a battery management system, the method comprising: checking an SoH of each of a plurality of battery modules included in a battery pack; checking at least one first battery module, which is at least a part of the plurality of battery modules, based on at least a part of the SoH of each of the plurality of battery modules; and re-checking the SoH of the at least one first battery module by considering at least a part of a margin capacity of the at least one first battery module as an available capacity.

[0008] In one embodiment of the present disclosure, the step of identifying the at least one first battery module may include a battery SoH management method including: a step of identifying, based on at least some of the SoHs of each of the plurality of battery modules, that at least one of the difference information between the SoHs of each of the plurality of battery modules is greater than or equal to a first threshold; and a step of identifying, as the at least one first battery module, at least one battery module having a relatively small SoH among the corresponding battery modules for each of the at least one difference information that is greater than or equal to the first threshold.

[0009] In addition, in one embodiment of the present disclosure, the step of identifying the at least one first battery module may include a battery SoH management method including the step of identifying, based on at least some of the SoHs of each of the plurality of battery modules, that at least one of the SoHs is below a second threshold; and the step of identifying at least one battery module corresponding to the SoH below the second threshold as the at least one first battery module.

[0010] In addition, in one embodiment of the present disclosure, the step of re-verifying the SoH of the at least one first battery module may include a battery SoH management method including the steps of: verifying a first SoH corresponding to a battery module remaining among the plurality of battery modules excluding the at least one first battery module; verifying, based on the first SoH, at least a portion of the capacity to be considered as the available capacity among the margin capacity; and re-verifying the SoH of the at least one first battery module based on the at least a portion of the capacity to be considered as the available capacity.

[0011] In addition, in one embodiment of the present disclosure, a battery SoH management method may be included, further comprising: a step of confirming that the SoH of at least some of the plurality of battery modules is equal to or lower than a second threshold; a step of confirming that, for at least one battery module corresponding to the SoH being equal to or lower than the second threshold, a ratio of the margin capacity considered as available capacity is equal to or higher than a third threshold; and a step of transmitting replacement information related to the replacement of the battery pack to a manager terminal.

[0012] In addition, in one embodiment of the present disclosure, the step of checking the at least one first battery module may include a battery SoH management method including a step of checking that at least some of the SoH of each of the plurality of battery modules is less than a second threshold; and a step of checking that at least some of the remaining battery modules, excluding the first battery module having the SoH greater than or equal to the second threshold, among the plurality of battery modules, have been replaced with at least one second battery module.

[0013] Additionally, in one embodiment of the present disclosure, the step of confirming that at least some of the SoH of each of the plurality of battery modules is below the second threshold may include a battery SoH management method including a step of transmitting replacement information related to replacement of at least some of the remaining battery modules to a manager terminal.

[0014] In addition, in one embodiment of the present disclosure, the step of re-verifying the SoH of the at least one first battery module may include a battery SoH management method including: a step of verifying a second SoH corresponding to the at least one second battery module; a step of verifying, based on the second SoH, at least a portion of the capacity to be considered as the available capacity among the margin capacity; and a step of re-verifying the SoH of the at least one first battery module based on the at least a portion of the capacity to be considered as the available capacity.

[0015] Another aspect of the present disclosure provides a battery management system for managing a battery state-of-health (SoH), comprising: a processor; and a memory storing one or more instructions, wherein the processor is configured to perform the one or more instructions to: verify the SoH of each of a plurality of battery modules included in a battery pack; verify at least one first battery module, which is at least one of the plurality of battery modules, based on at least a portion of the SoH of each of the plurality of battery modules; and re-verify the SoH of the at least one first battery module by considering at least a portion of a margin capacity of the at least one first battery module as an available capacity.

[0016] Another aspect of the present disclosure may provide a computer-readable, non-transitory recording medium having recorded thereon a program for executing the battery health status management method described above on a computer.

[0017] Specific details of other embodiments are included in the detailed description and drawings.

[0018] According to the proposed embodiment, one or more of the following effects can be expected.

[0019] According to an embodiment of the present specification, by managing SoH based on the margin capacity of the battery module, the non-replaced module can have a similar SoH to the newly replaced module, and thus the newly replaced module can be used without wasting performance.

[0020] Additionally, according to the embodiment of the present specification, by managing SoH based on the margin capacity of the battery module, even if a specific battery module ages faster than other modules, the SoH of the entire battery pack can be prevented from deteriorating due to this.

[0021] In addition, according to the embodiment of the present specification, by managing the SoH of the battery modules to be generally similar to each other based on the margin capacity of the battery modules, uniform performance can be maintained and battery life can be optimized.

[0022] The effects of the present disclosure are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0023] FIG. 1 is a diagram showing the interlocking relationship between a battery management system and a battery pack that manages a battery health status according to one embodiment.

[0024] Figure 2 is a flowchart of a SoH management method according to one embodiment.

[0025] Figures 3a and 3b are exemplary drawings showing changes in SoH according to a SoH re-verification process according to one embodiment.

[0026] FIGS. 4a and 4b are exemplary diagrams showing changes in SoH according to a SoH re-verification process according to one embodiment.

[0027] FIGS. 5a and 5b are exemplary drawings showing changes in SoH when a battery module is replaced, according to one embodiment.

[0028] FIG. 6 is a diagram showing the interworking relationship between a battery management system for managing a battery health status according to one embodiment and a battery pack designed in another manner.

[0029] FIG. 7 illustrates a block diagram of a battery management system according to one embodiment.

[0030] The terms used in the examples have been selected from widely used, current terms, taking into account the functions of the present disclosure. However, these terms may vary depending on the intentions of those skilled in the art, precedents, the emergence of new technologies, etc. Furthermore, in certain cases, terms may be arbitrarily selected by the applicant, in which case their meanings will be described in detail in the relevant description. Therefore, the terms used in this disclosure should not be defined simply as names, but rather based on the meanings of the terms and the overall content of the present disclosure.

[0031] When a part of a specification is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise stated.

[0032] The expression "at least one of a, b, and c" described throughout the specification may encompass 'a alone', 'b alone', 'c alone', 'a and b', 'a and c', 'b and c', or 'all of a, b, and c'.

[0033] The "terminal" mentioned below may be implemented as a computer or portable terminal that can connect to a server or other terminal via a network. Here, the computer includes, for example, a notebook, desktop, laptop, etc. equipped with a web browser, and the portable terminal may include, for example, a wireless communication device that guarantees portability and mobility, and may include all types of handheld-based wireless communication devices such as communication-based terminals such as IMT (International Mobile Telecommunication), CDMA (Code Division Multiple Access), W-CDMA (W-Code Division Multiple Access), LTE (Long Term Evolution), smartphones, tablet PCs, etc.

[0034] Below, embodiments of the present disclosure are described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present disclosure. However, the present disclosure may be implemented in various different forms and is not limited to the embodiments described herein.

[0035] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0036] FIG. 1 is a diagram showing the interlocking relationship between a battery management system and a battery pack that manages a battery health status according to one embodiment.

[0037] Referring to FIG. 1, the battery management system (100) may include a computing device, sensors, and various other equipment used to manage a battery pack (200). Here, the sensors may include various sensors used to manage the battery, such as a current sensor, a voltage sensor, a temperature sensor, an insulation resistance sensor, and a status measurement sensor, and the equipment may include, but is not limited to, a communication interface, a balancing circuit, and the like.

[0038] A battery pack (200) may include a plurality of battery modules, and each battery module may include a plurality of battery cells. Specifically, as shown in FIG. 1, a battery module (210) may include a battery cell (211).

[0039] In one embodiment, the battery pack (200) may be a product designed to output a specific capacity. In this case, the battery pack (200) is generally designed to theoretically output more than the specific capacity, but in actual use, it may be set to output only up to the specific capacity. For example, if the battery pack (200) is intended to be used as a battery capable of outputting a rated capacity of 1000 Wh, it may be designed to actually output a capacity of 1200 Wh. In other words, the battery pack (200) may be designed to have a margin capacity, and may be set by the battery management system (100) to use only the initial capacity obtained by subtracting the margin capacity from the total capacity. In the example described above, the total capacity may be 1200 Wh, the margin capacity may be 200 Wh, and the initial capacity may be 1000 Wh, and the initial capacity of the battery pack (200) of 1000 Wh may be set to be used by the battery management system (100). Such capacity setting of the battery pack (200) may be performed to ensure safety during use and to provide a margin to ensure that the required output capacity can be output from a quality control perspective.

[0040] According to one embodiment, the battery pack (200) may age depending on use. The degree of such aging may be determined by the battery's State-of-Health (SoH) value, which may be calculated as the ratio of the available capacity of the battery pack (200) at the initial point in time to the available capacity at the time of determination. For example, if the initial capacity of the battery pack (200) is set to 1000 Wh as described above, the available capacity may be initially measured as 1000 Wh, but if the available capacity decreases to 950 Wh as the battery pack (200) is used, the SoH of the battery pack (200) at that point in time may be calculated as 95%. According to the prior art, the margin capacity may not be considered in such SoH calculation.

[0041] In addition, when calculating the SoH of the battery pack (200), it is not measured by simply adding up the available capacities of each battery module included in the battery pack (200) and then calculating the ratio with the initial available capacity. Specifically, in order to calculate the SoH of the battery pack (200), the SoH of each battery module included therein is checked, and the lowest SoH among the SoHs of the battery pack (200) can be checked as the SoH of the battery pack (200). For example, if there are 10 battery modules, all of which had an initial capacity of 100 Wh, and the battery module in the best condition still has an available capacity of 97 Wh, so that the SoH is 97%, but the battery module in the worst condition has an available capacity of only 85 Wh, so that the SoH is calculated as 85%, then the SoH of the battery pack (200) is measured as 85%, and can be managed and used based on this low SoH value. While this conventional SoH measurement and management method has its advantages, it can be inefficient because it cannot fully utilize the performance of battery modules with more remaining capacity. Furthermore, because this SoH measurement method completely ignores margin capacity, this inefficiency is likely to be exacerbated.

[0042] According to one embodiment, the SoH of each battery module is measured by taking the aforementioned margin capacity into account, and the SoH of the battery pack (200) is calculated based on the SoH of the battery module for which the margin capacity is taken into account, thereby enabling more efficient use of the battery pack (200). A SoH management method of this kind will be described below.

[0043] Figure 2 is a flowchart of a SoH management method according to one embodiment.

[0044] Referring to FIG. 2, in step S210, the battery management system (100) can check the SoH of each of the plurality of battery modules included in the battery pack (200). In step S220, the battery management system (100) can check at least one first battery module, which is at least a part of the plurality of battery modules, based on at least a part of the SoH of each of the plurality of battery modules. In step S230, the battery management system (100) can recheck the SoH of at least one first battery module by considering at least a part of the margin capacity of the at least one first battery module as the available capacity. Each step will be described in more detail below.

[0045] First, as described above, the battery management system (100) can verify the SoH of each battery module. Here, verification of the SoH can be performed in various ways. For example, based on the various sensors and equipment described above, the SoH can be verified using various techniques, such as charge / discharge capacity measurement, internal resistance measurement, voltage analysis, coulombic efficiency measurement, impedance spectroscopy, or an estimation method using artificial intelligence. However, the present invention is not limited to these methods.

[0046] Thereafter, the battery management system (100) can identify the first battery module based on at least some of the SoH of each of the plurality of battery modules. Various embodiments of identifying the first battery module will be described below.

[0047] First, according to one embodiment, the battery management system (100) can determine that at least one of the difference information between the SoHs of each of the plurality of battery modules is greater than or equal to a first threshold based on at least a portion of the SoHs of each of the plurality of battery modules. For example, in the case where there are 10 battery modules, the difference information between the SoHs can be calculated for each of 45 combinations, and it can be determined that at least one of the 45 combinations is greater than or equal to the first threshold. For two battery modules corresponding to at least one piece of difference information whose difference is greater than or equal to the first threshold, the battery management system (100) can determine at least one module having a relatively smaller SoH as at least one first battery module. For example, if the difference information is greater than or equal to the first threshold, the combination may include a battery module having a large SoH and a battery module having a small SoH, and among these, the battery module having the smaller SoH can be determined as the first battery module. For a more specific example, if the first threshold corresponds to 5%, and a specific combination of battery modules has SoH of 91% and 85%, respectively, then the specific combination corresponds to difference information greater than the first threshold, and here, the battery module having SoH of 85% can be identified as the first battery module mentioned above.

[0048] In one embodiment, the first threshold may be set to a predetermined value that allows for confirmation that a specific battery module is aging faster than other battery modules. A specific value may be approximately 5%, but is not limited thereto. The above first battery module confirmation method may basically be intended to confirm a battery module that is aging faster than other battery modules and has a decreasing SoH as the first battery module. Therefore, various methods other than the above-described method may be applied as long as they can achieve this purpose.

[0049] Thereafter, the battery management system (100) can check the first SoH corresponding to the remaining battery modules excluding at least one first battery module among the plurality of battery modules. According to one embodiment, the battery management system (100) can check a value that can represent the SoH of the remaining battery modules as the first SoH. For example, the average or median value of the SoH of the remaining battery modules can be checked as the first SoH, but the present invention is not limited thereto. The battery management system (100) can check at least a portion of the capacity to be considered as the available capacity among the margin capacity based on the first SoH. For example, the battery management system (100) calculates the difference information between the available capacity of the first battery module at the corresponding point in time and the capacity corresponding to the first SoH, compares the size between the difference information and the margin capacity, and if the difference information is smaller than the margin capacity, the amount of the difference information can be checked as the available capacity from the margin capacity. If the difference information is larger than the margin capacity, the entire margin capacity can be checked as the available capacity. For example, if the available capacity of the first battery module at the given time is 84Wh and the first SoH is 91%, the difference information between the capacity corresponding to the first SoH, 91Wh, and the available capacity can be calculated as 7Wh. If the margin capacity is 20Wh, the battery management system (100) can confirm only the difference information of 7Wh among the margin capacity of 20Wh as the available capacity of the first battery module. If the margin capacity is 5Wh, the entire 5Wh can be confirmed as the available capacity of the first battery module. This confirmation process can be performed for each first battery module.

[0050] Thereafter, the battery management system (100) can re-verify the SoH of at least one first battery module based on at least a portion of the capacity to be considered as available capacity among the margin capacity. For example, the battery management system (100) can re-verify the SoH of the first battery module based on the ratio of the total capacity and the available capacity at the initial point in time, by adding at least a portion of the capacity to be considered as available capacity among the aforementioned margin capacity to the available capacity confirmed at the time point before applying the margin capacity. This process can be performed for each first battery module. To take the numerical values ​​of the above-mentioned example again, the battery management system (100) can re-verify the SoH based on 91 Wh, which is the available capacity of the first battery module before applying the margin capacity, plus 7 Wh, which is newly considered as available capacity. The change in SoH according to the SoH re-verification process can be visually confirmed with reference to FIGS. 3a and 3b. In FIGS. 3a to 5a and 3b to 5b below, a white square (10) may represent the SoH of each battery module to which the SoH re-verification process according to an embodiment of the present disclosure is not applied, a dotted square (30) may represent a margin capacity, and a hatched square (20) may represent a capacity considered as an available capacity among the margin capacities. In addition, since FIGS. 3a to 5a depict the SoH of a battery before the SoH re-verification process according to an embodiment of the present disclosure is applied, the hatched square (20) may not be displayed.

[0051] Figures 3a and 3b are exemplary drawings showing changes in SoH according to a SoH re-verification process according to one embodiment.

[0052] Referring to FIG. 3A, it can be seen that the modules (311, 321, and 331) prior to the SoH re-verification process have SoHs of 91%, 85%, and 91%, respectively, with their available capacities decreasing compared to the initial available capacity (301) when the SoH was 100%. Here, a battery pack including such modules (311, 321, and 331) can be used and managed based on having an SoH of 85%, such as the second module (321), according to the prior art. However, each battery module is designed to have a margin capacity, and using it based on an SoH of 85% while leaving the margin capacity of 20% unused can be viewed as a waste of performance.

[0053] Referring to FIG. 3b, an example of a situation where performance waste that could occur in a situation like FIG. 3a is prevented by applying the SoH management method according to the present disclosure can be confirmed. For example, the second module (322) whose SoH has been reconfirmed by applying margin capacity can be confirmed to have 91% SoH, the same as the other modules (312 and 332), by considering 6% of the margin capacity as available capacity, unlike FIG. 3a. This allows the battery pack to be managed and used as having 91% SoH, thereby preventing performance waste.

[0054] Below, another embodiment of verifying the first battery module is described.

[0055] According to one embodiment, the battery management system (100) may determine, based on at least a portion of the SoH of each of a plurality of battery modules, that at least one of the SoHs is below a second threshold. Thereafter, at least one battery module corresponding to an SoH below the second threshold may be identified as at least one first battery module. Here, the second threshold may correspond to an SoH value at which the battery is deemed to be aging and in need of replacement. A specific value may be, for example, approximately 80%, but is not limited thereto. According to this embodiment, a battery module whose SoH falls below a threshold associated with aging may be selected as the first battery module.

[0056] At this time, the battery management system (100) can, similarly to the process described above, confirm at least a portion of the capacity to be considered as the available capacity among the margin capacity. Thereafter, the SoH of the first battery module can be re-verified based on at least a portion of the capacity described above. Here, at least a portion of the capacity to be considered as the available capacity among the margin capacity may be determined by calculating, similarly to the process described above, the difference information between a specific value corresponding to the SoH of the remaining modules excluding the first battery module and the SoH of the first battery module, comparing the difference information with the margin capacity of the first battery module, and then considering the smaller amount of the two as the available capacity. Alternatively, in another embodiment, the battery management system (100) may calculate the difference information between the second threshold value and the SoH of the first battery module, comparing the difference information with the margin capacity of the first battery module, and then considering the smaller amount of the two as the available capacity. The SoH re-verification process can be performed by performing this process for each first battery module. The changes in SoH according to the SoH reconfirmation process can be visually confirmed by referring to Figures 4a and 4b.

[0057] FIGS. 4a and 4b are exemplary diagrams showing changes in SoH according to a SoH re-verification process according to one embodiment.

[0058] Referring to FIG. 4A, it can be seen that the modules (411, 421, and 431) prior to the SoH re-verification process have SoHs of 82%, 79%, and 83%, respectively, with their available capacities decreasing compared to the initial available capacity (401) when the SoH was 100% as they are used. Here, according to the prior art, since the SoH of a battery pack including such modules (411, 421, and 431) is calculated as 79% of that of the second module (421), it can be recognized that the battery pack is aging and needs to be replaced. However, since each battery module is designed to have a margin capacity, replacing a battery pack when the margin capacity has not yet been used can be seen as wasting the remaining margin capacity.

[0059] Referring to FIG. 4b, an example of a situation where waste of margin capacity, which may occur in a situation like FIG. 4a, is prevented by applying the SoH management method according to the present disclosure. For example, by applying 2% of the margin capacity as available capacity and reconfirming the SoH of the second module (422) at 81%, the battery pack is determined to have a higher SoH than the 80% SoH, which indicates aging and requires replacement. Therefore, the battery pack can be used for a longer period of time without replacement.

[0060] The two methods for verifying the first battery module described above can be applied together. For example, a battery module whose SoH decreases significantly faster than other battery modules can be verified as the first battery module through selection based on a first threshold, or a battery module determined to be aged can be verified as the first battery module through selection based on a second threshold, and the SoH re-verification method of the present disclosure described above can be applied. Accordingly, by re-verifying the SoH by applying a margin capacity to a battery module that deteriorates faster than other battery modules or a battery module determined to be aged, efficiency can be improved in terms of battery pack use and management.

[0061] Furthermore, the SoH re-verification method of the present disclosure can be continuously performed during the use of the battery pack. For example, although the examples of FIGS. 3 and 4 both depict a case where the margin capacity is first applied after the margin capacity was at 20% with no margin capacity used at all, alternatively, an embodiment in which the margin capacity is sequentially and continuously applied is also possible. For example, in the example of FIG. 3b, if the SoH of the second battery module (322) is again 6% lower than that of the other modules (312 and 332), the margin capacity corresponding to 6% SoH can be additionally applied to bring the SoH back to normal. This will reduce the margin capacity to a capacity corresponding to 8%. Similarly, in the example of FIG. 4b, if the SoH of the second module (422) again drops to 79%, the margin capacity corresponding to 2% SoH can be re-applied to bring the SoH back to 81%. Accordingly, the margin capacity may be reduced to a capacity corresponding to 16%. In the examples of FIGS. 3b and 4b, the margin capacity may also be applied to other battery modules instead of the second battery module (322 and 422).

[0062] While continuously consuming the margin capacity in this way, the battery management system (100) can confirm that the SoH of at least some of the plurality of battery modules is below the second threshold, and can confirm that the ratio of the margin capacity considered as available capacity for at least one battery module corresponding to the SoH below the second threshold is above the third threshold. Accordingly, the battery management system (100) can transmit replacement information related to the replacement of the battery pack to the administrator terminal. That is, the battery management system (100) continuously applies the margin capacity to recalculate and use the SoH, and when it is confirmed that the ratio of the margin capacity considered as available capacity reaches above the third threshold, i.e., the margin capacity is almost completely consumed, the battery management system can induce the replacement of the battery pack by transmitting the replacement information related to the replacement of the battery pack to the administrator terminal. In this way, by using the capacity of the battery pack to the limit, efficiency can be promoted.

[0063] Below, another embodiment related to the first battery module verification method is described.

[0064] According to one embodiment, the battery management system (100) can confirm that at least some of the SoH of each of the plurality of battery modules is below a second threshold. The battery management system (100) can confirm that a battery module having an SoH greater than or equal to the second threshold is a first battery module. In addition, the battery management system (100) can confirm that at least some of the remaining battery modules excluding the first battery module have been replaced with at least one second battery module. According to one embodiment, the second battery module may be a new battery module installed to replace the remaining aged battery modules excluding the first battery module, and thus, the SoH may have a value that is 100% or higher than the SoH of the existing aged battery modules. In this case, the replacement of the remaining battery modules with the second battery module may be performed when replacement information related to the replacement of at least some of the remaining battery modules is transmitted to the manager terminal.

[0065] The battery management system (100) can check the second SoH corresponding to the second battery module. Thereafter, based on the second SoH, at least a portion of the capacity to be considered as available capacity among the margin capacity can be checked. For example, the battery management system can calculate difference information between the second SoH and the SoH of the first battery module at the corresponding point in time. Thereafter, the difference information and the margin capacity can be compared, and the capacity corresponding to the smaller value of the two can be considered as available capacity among the margin capacity. For example, if the second SoH corresponds to 100% and the SoH of the first battery module at the corresponding point in time is 83%, and the margin capacity remains in an amount corresponding to 20% of the SoH, the battery management system (100) can restore the SoH to 100% by considering the capacity corresponding to 17% of the SoH as available capacity among the margin capacity. As a similar example, if the second SoH corresponds to 95% and the SoH of the first battery module at that point is 87%, the battery management system (100) can restore the SoH to 95%, the same as that of the newly installed second battery module, by considering the capacity corresponding to 8% as the available capacity among the margin capacity. If, in the latter example, only the amount of margin capacity remaining corresponds to 5% of the SoH, the entire remaining margin capacity corresponding to 5% of the SoH can be considered as the available capacity. Through the SoH restoration of the battery module described above, the SoH of the entire battery pack can be restored, and the effect of battery module replacement can be further enhanced. To examine this effect, refer to FIGS. 5a and 5b.

[0066] FIGS. 5a and 5b are exemplary drawings showing changes in SoH when a battery module is replaced, according to one embodiment.

[0067] Referring to FIG. 5A, it can be seen that the battery modules (511, 521, and 531) have SoHs of 82%, 79%, and 83%, respectively, with their available capacities decreasing compared to the initial available capacity (501) when the SoH was 100% as they are used. Here, since the SoH of the second module (521) is 79%, it can be replaced. However, according to the prior art, if only the second battery module (521) is replaced, since the SoH of the other battery modules is 82% and 83%, respectively, even if a new battery module is installed, the SoH of the battery pack can still be calculated as 82% and used and managed.

[0068] Referring to FIG. 5b, by applying the SoH management method according to the present disclosure, an example can be confirmed in which the SoH of the battery pack is restored to 100% even when only the second battery module (521) is replaced in a situation like FIG. 5a. That is, when the second module (522) is replaced with a new one, the battery management system (100) can ensure that the SoH of all battery modules of the battery pack has a value close to or equal to 100% by applying margin capacity to the first battery module (512) and the third battery module (523). Accordingly, even when only one battery module is replaced, the SoH of the battery pack can be effectively increased.

[0069] The embodiment of verifying the first battery module in relation to the replacement of the battery module described above and the embodiment of verifying the first battery module based on the first threshold and the second threshold described earlier may be applied together. For example, by applying a margin capacity to a battery module whose SoH decreases significantly faster than other battery modules or an aged battery module, the SoH may be continuously rechecked during battery use, and when the aged battery module is eventually replaced, the margin capacity may be applied to the remaining battery modules to maximize the effect of the battery module replacement.

[0070] According to one embodiment, the battery management system (100) can control each battery module and battery pack (200) to be used based on the re-confirmed SoH when the SoH is re-confirmed according to the above-described embodiments. That is, the first battery module can be controlled to be used up to a capacity corresponding to the re-confirmed SoH. At this time, since the SoH of the first battery module can also be determined based on the lowest SoH of the battery cells included therein, the battery management system (100) can control each battery cell included in the first battery module to be used up to a capacity corresponding to the re-confirmed SoH.

[0071] The SoH management method of the present disclosure described above has been described assuming a situation in which a battery module is optimized by applying margin capacity, and thus a battery pack is optimized, but it can also be applied to other situations. For example, the SoH management method of the present disclosure can be applied to a situation in which a battery cell, instead of a battery module, is optimized by applying margin capacity, and thus a battery module, instead of a battery pack, is optimized. Since the relationship between a battery pack and a module is hierarchical, similar to the relationship between a battery module and a cell, the SoH management method of the present disclosure can be applied similarly.

[0072] Additionally, the SoH management method of the present disclosure can be applied to batteries that do not have a cell-module-pack hierarchical structure as described above. Refer to FIG. 6 for a description of such an embodiment.

[0073] FIG. 6 is a diagram showing the interworking relationship between a battery management system for managing a battery health status according to one embodiment and a battery pack designed in another manner.

[0074] Referring to FIG. 6, the battery management system (100) can manage the SoH of a battery pack (600) designed with a cell-to-pack (CTP) structure. Here, the CTP structure is a structure in which battery cells are directly integrated into the battery pack without a module-level assembly process, and is a structure that has recently been receiving attention in terms of improving energy density, simplifying the manufacturing process, reducing weight, and improving cooling system efficiency. The SoH management method according to the present disclosure can also be applied to the battery pack (600) with such a CTP structure. For example, the SoH of the battery pack (600) with a CTP structure can be determined according to the lowest SoH among the SoHs of the plurality of battery cells (601) included therein. In such a case, the lowest SoH can be improved by applying a margin capacity according to the SoH management method according to the various embodiments described above. As described above, by applying the SoH management method of the present disclosure, the performance of the battery pack (600) with a CTP structure can be improved and its lifespan can be extended.

[0075] FIG. 7 illustrates a block diagram of a battery management system according to one embodiment.

[0076] According to one embodiment, the battery management system (100) may include a memory (101) and a processor (102). The battery management system (100) illustrated in FIG. 7 only illustrates components related to the present embodiment. Therefore, those skilled in the art will appreciate that, in addition to the components illustrated in FIG. 7, other general-purpose components may be included. In one embodiment, the processor (102) may be included in a controller.

[0077] The processor (102) can control the overall operation of the battery management system (100) and process data and signals. The processor (102) can be composed of at least one hardware unit. In addition, the processor (102) can operate by one or more software modules generated by executing program codes stored in the memory (101). The processor (102) can include a memory, and the processor (102) can control the overall operation of the battery management system (100) and process data and signals by executing the program codes stored in the memory.

[0078] The processor (102) may be configured to perform one or more instructions to: verify an SoH of each of a plurality of battery modules included in a battery pack; verify at least one first battery module, which is at least a part of the plurality of battery modules, based on at least a part of the SoH of each of the plurality of battery modules; and re-verify the SoH of the at least one first battery module by considering at least a part of the margin capacity of the at least one first battery module as available capacity.

[0079] In some embodiments, the battery management system (100) may additionally include a transceiver for performing wired / wireless communication. The battery management system (100) may communicate with an external battery management system using the transceiver. The external battery management system may be a terminal or a server. In addition, communication technologies used by the transceiver may include GSM (Global System for Mobile communication), CDMA (Code Division Multi Access), LTE (Long Term Evolution), 5G, WLAN (Wireless LAN), Wi-Fi (Wireless-Fidelity), Bluetooth (Bluetooth), RFID (Radio Frequency Identification), Infrared Data Association (IrDA), ZigBee, NFC (Near Field Communication), etc.

[0080] The battery management system according to the above-described embodiments may include a processor, a memory for storing and executing program data, permanent storage such as a disk drive, a communication port for communicating with an external device, a user interface device such as a touch panel, a key, a button, etc. The methods implemented as software modules or algorithms may be stored on a computer-readable recording medium as computer-readable codes or program instructions executable on the processor. Here, the computer-readable recording medium includes a magnetic storage medium (e.g., read-only memory (ROM), random-access memory (RAM), floppy disk, hard disk, etc.) and an optical reading medium (e.g., CD-ROM, DVD: Digital Versatile Disc)). The computer-readable recording medium may be distributed to computer systems connected to a network, so that the computer-readable code may be stored and executed in a distributed manner. The medium may be readable by a computer, stored in a memory, and executed by a processor.

[0081] The present embodiment may be represented by functional block configurations and various processing steps. These functional blocks may be implemented by various hardware and / or software configurations that perform specific functions. For example, the embodiment may employ direct circuit configurations such as memory, processing, logic, look-up tables, etc., which may perform various functions under the control of one or more microprocessors or other control devices. Similarly, the present embodiment may be implemented in a programming or scripting language such as C, C++, Java, assembler, etc., including various algorithms implemented as a combination of data structures, processes, routines, or other programming configurations. Functional aspects may be implemented as algorithms that execute on one or more processors. Furthermore, the present embodiment may employ conventional techniques for electronic configuration, signal processing, and / or data processing. Terms such as "mechanism," "element," "means," and "composition" can be used broadly and are not limited to mechanical or physical structures. These terms can also encompass a series of software routines, such as those associated with a processor.

[0082] The above-described embodiments are merely examples, and other embodiments may be implemented within the scope of the claims set forth below.

Claims

1. In a method for managing the battery state-of-health (SoH) of a battery management system, A step of checking the SoH of each of a plurality of battery modules included in a battery pack; A step of identifying at least one first battery module, which is at least a part of the plurality of battery modules, based on at least a part of the SoH of each of the plurality of battery modules; and A battery SoH management method comprising a step of re-verifying the SoH of the at least one first battery module by considering at least a portion of the margin capacity of the at least one first battery module as available capacity.

2. In paragraph 1, The step of verifying at least one first battery module is: A step of confirming that at least one of the difference information between the SoHs of each of the plurality of battery modules is greater than or equal to a first threshold based on at least a portion of the SoHs of each of the plurality of battery modules; and A battery SoH management method, comprising a step of identifying at least one battery module having a relatively small SoH among battery modules corresponding to at least one difference information equal to or greater than the first threshold as the at least one first battery module.

3. In paragraph 1, The step of verifying at least one first battery module is: a step of confirming that at least one of the respective SoHs is below a second threshold based on at least some of the SoHs of each of the plurality of battery modules; and A battery SoH management method comprising a step of identifying at least one battery module corresponding to the SoH being less than or equal to the second threshold as the at least one first battery module.

4. In paragraph 1, The step of reconfirming the SoH of at least one first battery module comprises: A step of confirming a first SoH corresponding to the remaining battery modules excluding at least one first battery module among the plurality of battery modules; Based on the first SoH, a step of identifying at least a portion of the margin capacity to be considered as the available capacity; and A battery SoH management method comprising the step of re-verifying the SoH of the at least one first battery module based on at least a portion of the capacity to be considered as the available capacity.

5. In paragraph 1, A step of confirming that the SoH of at least some of the plurality of battery modules is below a second threshold; A step of confirming that, for at least one battery module corresponding to the SoH lower than the second threshold, the ratio of the margin capacity considered as available capacity is higher than the third threshold; and A battery SoH management method further comprising a step of transmitting replacement information related to replacement of the battery pack to a manager terminal.

6. In paragraph 1, The step of verifying at least one first battery module is: A step of confirming that at least some of the SoH of each of the plurality of battery modules is less than a second threshold; A battery SoH management method comprising a step of confirming that at least some of the remaining battery modules, excluding the first battery module having an SoH greater than or equal to the second threshold among the plurality of battery modules, have been replaced with at least one second battery module.

7. In paragraph 6, The step of confirming that at least some of the SoH of each of the plurality of battery modules is less than the second threshold is: A battery SoH management method comprising a step of transmitting replacement information related to replacement of at least some of the remaining battery modules to a manager terminal.

8. In paragraph 6, The step of reconfirming the SoH of at least one first battery module comprises: A step of identifying a second SoH corresponding to at least one second battery module; Based on the second SoH, a step of identifying at least a portion of the margin capacity to be considered as the available capacity; and A battery SoH management method comprising the step of re-verifying the SoH of the at least one first battery module based on at least a portion of the capacity to be considered as the available capacity.

9. A non-transitory computer-readable recording medium having recorded thereon a program for executing the method of any one of clauses 1 to 8 on a computer.

10. As a battery management system that manages the battery state-of-health (SoH), processor; and Contains memory that stores one or more instructions, A battery management system, wherein the processor is configured to perform one or more instructions to: check the SoH of each of a plurality of battery modules included in a battery pack; check at least one first battery module, which is at least a part of the plurality of battery modules, based on at least a part of the SoH of each of the plurality of battery modules; and recheck the SoH of the at least one first battery module by considering at least a part of the margin capacity of the at least one first battery module as an available capacity.

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