Apparatus and method for managing battery

Abstract

An apparatus for managing a battery according to an embodiment of the present invention includes: a profile acquisition unit configured to acquire a differential profile representing a corresponding relationship between a voltage and a differential capacity of the battery; and a control unit configured to determine a feature point included in a preset reference voltage section of the differential profile and determine the state of the battery on the basis of a result of determining the feature point.

Description

Battery management device and method

[0001] This application claims priority to Korean Patent Application No. 10-2024-0105530, filed on August 7, 2024, and all contents disclosed in the specification and drawings of the said application are incorporated herein by reference.

[0002] The present invention relates to a battery management device and method, and more particularly, to a battery management device and method for determining the state of a battery.

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

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

[0005] While extensive research is being conducted on these batteries to improve capacity and density, improving lifespan and safety are also crucial. To improve battery safety, technology that accurately assesses the current battery condition is required. In particular, as batteries increasingly incorporate not just a single active material but a mixture of multiple active materials, accurately assessing the battery condition becomes even more crucial.

[0006] The present invention has been devised to solve the above problems, and its purpose is to provide a battery management device and method capable of more accurately determining the state of a battery.

[0007] Other objects and advantages of the present invention can be understood through the following description and will be more clearly understood through the embodiments of the present invention. Furthermore, it will be readily apparent that the objects and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims.

[0008] A battery management device according to one aspect of the present invention may include a profile acquisition unit configured to acquire a differential profile indicating a correspondence between a voltage and a differential capacity of a battery; and a control unit configured to determine a characteristic point included in a preset reference voltage section of the differential profile and determine a state of the battery based on a result of determining the characteristic point.

[0009] The control unit may be configured to detect a peak and an inflection point in the reference voltage section of the differential profile, and determine the detected peak and the detected inflection point as the feature point.

[0010] The control unit may be configured to determine a target voltage section corresponding to a voltage higher than the peak voltage among the reference voltage sections, and to detect the inflection point in the target voltage section.

[0011] The control unit may be configured to determine the battery as a first battery including a first active material or a second battery including a second active material when only the peak is detected as the feature point.

[0012] The above control unit may be configured to divide the reference voltage section into a first reference voltage section and a second reference voltage section.

[0013] The control unit may be configured to determine the battery as the first battery if the detected peak is included in the first reference voltage range.

[0014] The control unit may be configured to determine the battery as the second battery if the detected peak is included in the second reference voltage range.

[0015] The control unit may be configured to determine the battery as a third battery including a first active material and a second active material when the peak and the inflection point are detected as the characteristic points.

[0016] The control unit may be configured to calculate a differential capacity ratio of the peak and the inflection point, and to calculate a mixing ratio of the first active material and the second active material included in the third battery based on the calculated differential capacity ratio.

[0017] The above control unit may be configured to set an upper limit voltage for the battery based on the determination result of the feature point.

[0018] The above control unit may be configured to set the upper limit voltage to a voltage value preset to correspond to the type of the battery when the determined characteristic point is one.

[0019] The control unit may be configured to calculate a differential capacity ratio between a plurality of characteristic points when there are two of the determined characteristic points, and to set the upper limit voltage by adding the differential capacity ratio to voltage values ​​preset to correspond to a type of battery having one corresponding characteristic point.

[0020] A battery pack according to another aspect of the present invention may include a battery management device according to one aspect of the present invention.

[0021] A battery management method according to another aspect of the present invention may include a profile acquisition step of acquiring a differential profile indicating a correspondence between a voltage and a differential capacity of a battery; a feature point determination step of determining a feature point included in a preset reference voltage section of the differential profile; and a battery state determination step of determining a state of the battery based on a result of determining the feature point.

[0022] According to another aspect of the present invention, a computer-readable recording medium may store a computer program for executing a battery management method, including a profile acquisition step of acquiring a differential profile indicating a correspondence between a voltage and a differential capacity of a battery; a feature point determination step of determining a feature point included in a preset reference voltage section of the differential profile; and a battery state determination step of determining a state of the battery based on a result of determining the feature point.

[0023] According to one aspect of the present invention, a battery management device has an advantage in that it can effectively detect the composition of an active material included in a battery as status information about the battery based on a differential profile of the battery.

[0024] In addition, the battery management device has the advantage of preventing the battery from being overcharged by setting an upper limit voltage optimized for the battery based on the composition of the active material of the battery, thereby increasing the lifespan of the battery.

[0025] The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0026] The following drawings attached to this specification serve to further understand the technical idea of ​​the present invention together with the detailed description of the invention described below, and therefore the present invention should not be interpreted as being limited to the matters described in such drawings.

[0027] FIG. 1 is a schematic diagram illustrating a battery management device according to one embodiment of the present invention.

[0028] FIG. 2 is a diagram schematically illustrating a battery profile according to one embodiment of the present invention.

[0029] Figures 3 to 7 are schematic drawings illustrating differential profiles according to one embodiment of the present invention.

[0030] FIG. 8 is a schematic drawing of a battery pack according to another embodiment of the present invention.

[0031] FIG. 9 is a schematic diagram illustrating a battery management method according to another embodiment of the present invention.

[0032] Terms or words used in this specification and claims should not be interpreted as limited to their usual or dictionary meanings, but should be interpreted as meanings and concepts that conform to the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the term to explain his or her own invention in the best possible manner.

[0033] Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, it should be understood that there may be various equivalents and modified examples that can replace them at the time of filing this application.

[0034] In addition, when describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description is omitted.

[0035] Terms that include ordinal numbers, such as first, second, etc., are used to distinguish one of the various components from the rest, and are not used to limit the components by such terms.

[0036] Throughout the specification, whenever a part 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.

[0037] Additionally, throughout the specification, when we say that a part is "connected" to another part, this includes not only cases where it is "directly connected" but also cases where it is "indirectly connected" with other elements in between.

[0038]

[0039] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0040] FIG. 1 is a schematic diagram illustrating a battery management device (100) according to one embodiment of the present invention.

[0041] Referring to FIG. 1, the battery management device (100) may include a profile acquisition unit (110) and a control unit (120).

[0042] Here, a battery refers to a physically separate, independent cell having a negative terminal and a positive terminal. For example, a lithium-ion battery or a lithium polymer battery may be considered a battery. Furthermore, the battery may be of a cylindrical type, a prismatic type, or a pouch type. Furthermore, a battery may also refer to a battery bank, a battery module, or a battery pack in which multiple cells are connected in series and / or parallel. For convenience of explanation, the term "battery" will be described herein below as referring to a single, independent cell.

[0043] The profile acquisition unit (110) can be configured to acquire a differential profile indicating a correspondence between the voltage and differential capacity of the battery.

[0044] For example, a battery profile (BP) is a profile that represents the relationship between voltage (V) and capacity (Q) when the battery's SOC is charged from a preset start SOC or 0% to a preset end SOC or 100%. As another example, a battery profile (BP) may represent the relationship between voltage (V) and capacity (Q) when the battery's SOC is discharged from a preset start SOC or 100% to a preset end SOC or 0%.

[0045] FIG. 2 is a diagram schematically illustrating a battery profile (BP) according to one embodiment of the present invention. In the embodiment of FIG. 2, the battery profile (BP) can be expressed as an XY graph in which the X-axis is set to capacity (Q) and the Y-axis is set to voltage (V). However, it should be noted that the battery profile (BP) of FIG. 2 is expressed in the form of a graph only for the convenience of explanation, and that there is no limitation on the format in which the battery profile (BP) is expressed as long as a correspondence between the capacity and voltage of the battery is shown.

[0046] For example, there are no specific restrictions on the C-rate during charging or discharging to generate a battery profile (BP). However, to obtain more accurate battery profiles (BP) and differential profiles, it is desirable to charge or discharge the battery at a low rate. For example, a battery profile (BP) can be generated during the process of charging or discharging the battery at 0.05C.

[0047] Furthermore, by differentiating the battery profile (BP) with respect to voltage, a differential profile representing the correspondence between the differential capacity (dQ / dV) and the voltage (V) can be generated. Here, the differential capacity refers to the value obtained by differentiating the capacity with respect to the voltage. In other words, the differential profile can be said to be a profile obtained by differentiating the battery profile (BP) with respect to the voltage.

[0048] FIGS. 3 to 7 are schematic diagrams illustrating a differential profile according to an embodiment of the present invention. In the embodiments of FIGS. 3 to 7, the differential profile can be expressed as an XY graph in which the X-axis is set to voltage (V) and the Y-axis is set to differential capacity (dQ). Note that, similar to the battery profile (BP), there is no limitation on the format in which the differential profile can be expressed as long as a corresponding relationship between the differential capacity and voltage of the battery is shown.

[0049] For example, the profile acquisition unit (110) can directly receive the differential profile of the battery from the outside. That is, the profile acquisition unit (110) can acquire the differential profile by receiving the differential profile through a wired and / or wireless connection to the outside.

[0050] As another example, the profile acquisition unit (110) can directly receive the battery profile (BP) of the battery from the outside. Furthermore, the profile acquisition unit (110) can differentiate the battery profile (BP) with respect to voltage to generate a differential profile. That is, the profile acquisition unit (110) can be connected to the outside via wires and / or wirelessly to receive the battery profile (BP) and directly generate a differential profile from the battery profile (BP), thereby acquiring the differential profile.

[0051] As another example, the profile acquisition unit (110) may receive battery information regarding the voltage and capacity of the battery. Furthermore, the profile acquisition unit (110) may generate a battery profile (BP) based on the received battery information, and may generate a differential profile based on the generated battery profile (BP). In other words, the profile acquisition unit (110) may directly generate a differential profile based on the battery information, thereby acquiring the differential profile.

[0052] The profile acquisition unit (110) may be connected to the control unit (120) so as to be able to communicate with it. For example, the profile acquisition unit (110) may be connected to the control unit (120) by wire and / or wirelessly. The profile acquisition unit may transmit the acquired differential profile to the control unit (120).

[0053] The control unit (120) may be configured to determine a feature point included in a preset reference voltage section (R) of the differential profile.

[0054] Specifically, the reference voltage section (R) may correspond to a portion of the entire voltage section of the differential profile. Furthermore, the battery's condition may be determined by characteristic points included in the reference voltage section (R). Accordingly, the control unit (120) may determine characteristic points for the reference voltage section (R) among the voltage sections of the differential profile.

[0055] More specifically, the control unit (120) may be configured to detect peaks and inflection points in the reference voltage section (R) of the differential profile.

[0056] Here, the peak represents a maximum point (a point with an upward convex shape) included in the differential profile. In other words, the rate of change of the differential capacitance with respect to voltage at the peak is 0, and the rate of change of the differential capacitance with respect to voltage can change from positive to negative based on the peak. For example, the control unit (120) can detect a peak corresponding to a maximum point in the reference voltage section (R) of the differential profile.

[0057] And, the inflection point indicates the point where the direction of the bend changes in the differential profile. Specifically, the inflection point of the differential profile (V-dQ / dV profile) indicates a peak (e.g., a maximum point) included in the second differential profile (Vd(dQ)dV profile) obtained by differentiating the differential profile with respect to voltage. For example, the control unit (120) can detect a peak corresponding to a maximum point in the reference voltage section (R) of the second differential profile of the differential profile, and detect the inflection point of the differential profile based on the detected peak.

[0058] The control unit (120) can be configured to determine the detected peak and the detected inflection point as feature points.

[0059] Specifically, if a peak is detected in the reference voltage section (R) of the differential profile, the control unit (120) may determine the detected peak as a feature point. Similarly, if an inflection point is detected in the reference voltage section (R) of the differential profile, the control unit (120) may determine the detected inflection point as a feature point. In other words, the feature point may include both the detected peak and the detected inflection point.

[0060] For example, if both a peak and an inflection point are detected in the reference voltage section (R) of the differential profile, the control unit (120) can determine both the detected peak and inflection point as feature points.

[0061] As another example, if a peak is detected in the reference voltage section (R) of the differential profile and an inflection point is not detected, the control unit (120) can determine the detected peak as a feature point.

[0062] As another example, if an inflection point is detected in the reference voltage section (R) of the differential profile and no peak is detected, the control unit (120) may not determine a feature point. Preferably, if no peak is detected, the control unit (120) may not determine a feature point even if an inflection point is detected.

[0063] As another example, if neither a peak nor an inflection point is detected in the reference voltage section (R) of the differential profile, the control unit (120) may not determine a feature point.

[0064] The control unit (120) may be configured to determine the state of the battery based on the result of determining the characteristic point.

[0065] Specifically, the control unit (120) can determine the state of the battery by determining the type of active material included in the battery based on the result of determining the characteristic point. Preferably, the control unit (120) can determine whether the battery includes a single active material or a mixed active material in which multiple active materials are mixed. For example, the control unit (120) can determine the state of the battery as a battery including a first active material, a battery including a second active material, or a battery including both a first active material and a second active material.

[0066] Specifically, the first active material and the second active material may be positive electrode active materials. Here, the positive electrode active material includes nickel (Ni), cobalt (Co), and manganese (Mn), and the first active material and the second active material may be distinguished based on the nickel content.

[0067] For example, the first active material has a nickel content of 80% or more of the positive electrode active material, and a battery including the first active material includes an NCM811 (Ni:Co:Mn=8:1:1) battery.

[0068] As another example, the second active material has a nickel content of 70% or less of the positive electrode active material, and batteries including the second active material include NCM712 (Ni:Co:Mn=7:1:2) batteries, NCM721 (Ni:Co:Mn=7:2:1) batteries, NCM622 (Ni:Co:Mn=6:2:2) batteries, NCM523 (Ni:Co:Mn=5:2:3) batteries, and NCM532 (Ni:Co:Mn=5:3:2) batteries.

[0069] That is, the battery management device (100) has the advantage of being able to non-destructively detect the composition of the active material included in the battery as status information about the battery based on the differential profile of the battery.

[0070]

[0071] Meanwhile, the profile acquisition unit (110) and the control unit (120) provided in the battery management device (100) may optionally include a processor, an application-specific integrated circuit (ASIC), another chipset, a logic circuit, a register, a communication modem, a data processing device, etc. known in the art to execute various control logics performed in the present invention. In addition, when the control logic is implemented in software, the profile acquisition unit (110) and the control unit (120) may be implemented as a set of program modules. At this time, the program modules may be stored in a memory and executed by the profile acquisition unit (110) and the control unit (120). The memory may be located inside or outside the profile acquisition unit (110) and the control unit (120), and may be connected to the profile acquisition unit (110) and the control unit (120) by various well-known means.

[0072] In addition, the battery management device (100) may further include a storage unit (130). The storage unit (130) may store data or programs required for each component of the battery management device (100) to perform operations and functions, or data generated in the process of performing operations and functions. The storage unit (130) is not particularly limited in type as long as it is a known information storage means known to be capable of recording, erasing, updating, and reading data. As an example, the information storage means may include RAM, flash memory, ROM, EEPROM, registers, etc. In addition, the storage unit (130) may store program codes defining processes executable by each component of the battery management device (100).

[0073]

[0074] Hereinafter, with reference to FIGS. 3 to 7, an embodiment in which the control unit (120) determines peaks and inflection points in a differential profile is specifically described. Here, the first to fifth differential profiles (DP1, DP2, DP3, DP4, DP5) are differential profiles for different batteries.

[0075] Preferably, the control unit (120) may be configured to determine a target voltage section corresponding to a voltage higher than the peak of the reference voltage section (R).

[0076] Specifically, the control unit (120) can first detect a peak in the reference voltage section (R) of the differential profile. When a peak is detected, the control unit (120) can determine a voltage section higher than the voltage of the peak among the reference voltage sections (R) as the target voltage section.

[0077] Here, the reference voltage range (R) is a preset voltage range that can include both peaks and inflection points, and is commonly applied to the battery (or differential profile) being diagnosed. That is, even if the differential profiles are for different batteries, the reference voltage range (R) is applied as a common voltage range. The reference voltage range (R) can be set as a voltage range from a preset start voltage (Va) to a preset upper limit voltage (Vb). For example, the reference voltage range (R) can be preset to 4.0 [V] to 4.35 [V].

[0078] The target voltage range can be determined as a voltage range from the peak voltage to a preset upper limit voltage. For example, assuming that the peak voltage is Vp[V] and the preset upper limit voltage is 4.35[V], the target voltage range can be determined as Vp[V] to 4.35[V].

[0079] Additionally, the control unit (120) can be configured to detect an inflection point in the target voltage range.

[0080] Specifically, the control unit (120) can detect an inflection point only for an area included in the target voltage section among the differential profiles.

[0081] In the embodiment of FIG. 3, the control unit (120) can detect a first peak (p1) in the reference voltage section (R) of the first differential profile (DP1). Then, the control unit (120) can determine a voltage section higher than or equal to the voltage of the first peak (p1) as a target voltage section. That is, the first target voltage section (TR1) of the first differential profile (DP1) can be determined as a section higher than or equal to 4.35 [V] of the voltage of the first peak (p1). Then, since the first target voltage section (TR1) does not include an inflection point, the control unit (120) may not detect an inflection point in the first target voltage section (TR1). Therefore, the control unit (120) can determine the first peak (p1) as a characteristic point for the battery.

[0082] In the embodiment of FIG. 4, the control unit (120) can detect the second peak (p2) in the reference voltage section (R) of the second differential profile (DP2). Then, the control unit (120) can determine a voltage section higher than or equal to the voltage of the second peak (p2) as a target voltage section. That is, the second target voltage section (TR2) of the second differential profile (DP2) can be determined as a section higher than or equal to 4.35 [V] of the voltage of the second peak (p2). Then, since the second target voltage section (TR2) does not include an inflection point, the control unit (120) may not detect the inflection point in the second target voltage section (TR2). Therefore, the control unit (120) can determine the second peak (p2) as a characteristic point for the battery.

[0083] In the embodiment of FIG. 5, the control unit (120) can detect a third peak (p3) in the reference voltage section (R) of the third differential profile (DP3). Then, the control unit (120) can determine a voltage section higher than or equal to the voltage of the third peak (p3) as a target voltage section. That is, the third target voltage section (TR3) of the third differential profile (DP3) can be determined as a section higher than or equal to 4.35 [V] of the voltage of the third peak (p3). Here, since the third target voltage section (TR3) includes an inflection point, the control unit (120) can detect the third inflection point (i3) in the third target voltage section (TR3). Therefore, the control unit (120) can determine the third peak (p3) and the third inflection point (i3) as characteristic points for the battery.

[0084] In the embodiment of FIG. 6, the control unit (120) can detect the fourth peak (p4) in the reference voltage section (R) of the fourth differential profile (DP4). Then, the control unit (120) can determine a voltage section higher than or equal to the voltage of the fourth peak (p4) as a target voltage section. That is, the fourth target voltage section (TR4) of the fourth differential profile (DP4) can be determined as a section higher than or equal to 4.35 [V] of the voltage of the fourth peak (p4). Here, since the fourth target voltage section (TR4) includes an inflection point, the control unit (120) can detect the fourth inflection point (i4) in the fourth target voltage section (TR4). Therefore, the control unit (120) can determine the fourth peak (p4) and the fourth inflection point (i4) as characteristic points for the battery.

[0085] In the embodiment of FIG. 7, the control unit (120) can detect the fifth peak (p5) in the reference voltage section (R) of the fifth differential profile (DP5). Then, the control unit (120) can determine a voltage section higher than or equal to the voltage of the fifth peak (p5) as a target voltage section. That is, the fifth target voltage section (TR5) of the fifth differential profile (DP5) can be determined as a section higher than or equal to 4.35 [V] of the voltage of the fifth peak (p5). Here, since the fifth target voltage section (TR5) includes an inflection point, the control unit (120) can detect the fifth inflection point (i5) in the fifth target voltage section (TR5). Therefore, the control unit (120) can determine the fifth peak (p5) and the fifth inflection point (i5) as characteristic points for the battery.

[0086] In the above embodiments, the reference voltage section (R) is the same as the voltage section of 4.0 [V] to 4.35 [V], but the first to fifth target voltage sections (TR5) can be determined to be the same or different from each other according to the voltages (Vp1, Vp2, Vp3, Vp4, Vp5) of the first to fifth peaks (p1, p2, p3, p4, p5).

[0087]

[0088] Below, an embodiment in which the control unit (120) determines the state of the battery based on the determined characteristic points is specifically described.

[0089] In one embodiment, the control unit (120) may be configured to determine the battery as a first battery including a first active material or a second battery including a second active material when only a peak is detected as a feature point.

[0090] Specifically, if a peak is detected in the reference voltage range (R), but no inflection point is detected in the target voltage range, the characteristic point may only include a peak. In this case, the control unit (120) may determine that the battery contains a single active material. Accordingly, the control unit (120) may determine the battery as a first battery containing a first active material or a second battery containing a second active material.

[0091] Here, the first battery and the second battery can be distinguished based on the voltage of the corresponding peak. That is, the battery can be distinguished as the first battery or the second battery depending on the magnitude of the voltage of the peak included in the reference voltage range (R).

[0092] More specifically, the control unit (120) may be configured to divide the reference voltage section (R) into a first reference voltage section (R1) and a second reference voltage section (R2).

[0093] The control unit (120) can divide the reference voltage section (R) into a first reference voltage section (R1) and a second reference voltage section (R2) based on a preset reference voltage. Here, the reference voltage is a voltage set to divide the reference voltage section (R) into the first reference voltage section (R1) and the second reference voltage section (R2). In particular, the reference voltage is commonly applied to the battery (or differential profile) to be diagnosed. That is, even if the differential profiles are for different batteries, the reference voltage is applied as a common voltage value.

[0094] For example, it is assumed that the reference voltage range (R) is a voltage range greater than or equal to the starting voltage (Va) and less than or equal to the upper limit voltage (Vb), and that the reference voltage is Vr[V]. Here, the relationship Va[V] < Vr[V] < Vb[V] is established.

[0095] The control unit (120) can set a voltage range of Va[V] or more and Vr[V] or less as a first reference voltage range (R1), and can set a voltage range of Vr[V] or more and Vb[V] or less as a second reference voltage range (R2).

[0096] For example, the control unit (120) may be configured to determine the battery as the first battery if the detected peak is included in the first reference voltage range (R1). As another example, the control unit (120) may be configured to determine the battery as the second battery if the detected peak is included in the second reference voltage range (R2).

[0097] Hereinafter, for the convenience of explanation, it is assumed that the reference voltage is preset to 4.2 [V]. That is, the control unit (120) can divide the reference voltage section (R, 4.0 [V] to 4.35 [V]) into a first reference voltage section (R1, 4.0 [V] to 4.2 [V]) and a second reference voltage section (R2, 4.2 [V] to 4.35 [V]) based on the reference voltage (4.2 [V]).

[0098] In the embodiment of FIG. 3, since the voltage of the first peak (p1) is lower than the reference voltage (4.2 [V]), the first peak (p1) may be included in the first reference voltage range (R1). Accordingly, the control unit (120) may determine the battery as a first battery including the first active material.

[0099] In the embodiment of FIG. 4, since the voltage of the second peak (p2) is greater than the reference voltage (4.2 [V]), the second peak (p2) may be included in the second reference voltage range (R2). Accordingly, the control unit (120) may determine the battery as a second battery including the second active material.

[0100] In another embodiment, the control unit (120) may be configured to determine the battery as a third battery including the first active material and the second active material when a peak and an inflection point are detected as characteristic points.

[0101] Specifically, when a peak is detected in the reference voltage section (R) and an inflection point is detected in the target voltage section, the control unit (120) may determine the battery as a third battery containing both the first active material and the second active material. Here, the third battery includes an active material in which the first active material and the second active material are blended.

[0102] In the embodiment of FIG. 5, a third peak (p3) is included in the reference voltage section (R), and a third inflection point (i3) is included in the third target voltage section (TR3). Here, the voltage of the third inflection point (i3) is Vi3 [V]. Therefore, the control unit (120) can determine the battery according to the embodiment of FIG. 5 as the third battery.

[0103] In the embodiment of FIG. 6, the reference voltage section (R) includes a fourth peak (p4), and the fourth target voltage section (TR4) includes a fourth inflection point (i4). Here, the voltage of the fourth inflection point (i4) is Vi4 [V]. Therefore, the control unit (120) can determine the battery according to the embodiment of FIG. 6 as the third battery.

[0104] In the embodiment of Fig. 7, the fifth peak (p5) is included in the reference voltage section (R), and the fifth inflection point (i5) is included in the fifth target voltage section (TR5). Here, the voltage of the fifth inflection point (i5) is Vi5 [V]. Therefore, the control unit (120) can determine the battery according to the embodiment of Fig. 7 as the third battery.

[0105] According to a battery management device (100) according to one embodiment of the present invention, the type of battery with an unclear composition can be distinguished or the composition of a manufactured battery can be verified in a non-destructive manner by analyzing a differential profile.

[0106]

[0107] Below, an embodiment in which the control unit (120) calculates the mixing ratio of the first active material and the second active material included in the third battery is specifically described.

[0108] The control unit (120) can be configured to calculate the differential capacity ratio of the peak and the inflection point.

[0109] Specifically, the control unit (120) can calculate the differential capacity ratio by calculating the ratio between the differential capacity of the peak and the inflection point. For example, the control unit (120) can calculate the differential capacity ratio by calculating the ratio of the differential capacity of the inflection point to the differential capacity of the peak.

[0110] Assume that the differential capacity of the peak is dQp and the differential capacity of the inflection point is dQi. Preferably, since the differential capacity of the peak is greater than the differential capacity of the inflection point, the control unit (120) can calculate the differential capacity ratio by calculating the formula "dQi÷dQp". Here, the inflection point means the point where the curve of the differential profile changes from concave (a shape that is convex upward) to convex (a shape that is convex downward). In the reference voltage section (R), the point that is convex upward is detected as a peak, and since the voltage of the inflection point is greater than the voltage of the peak, the differential capacity of the inflection point is less than the differential capacity of the peak.

[0111] In the embodiment of Fig. 5, the differential capacity of the third peak (p3) is dQp3, and the differential capacity of the third inflection point (i3) is dQi3. The control unit (120) can calculate the differential capacity ratio for the battery by calculating the formula “dQi3÷dQp3.”

[0112] In the embodiment of Fig. 6, the differential capacity of the fourth peak (p4) is dQp4, and the differential capacity of the third inflection point (i3) is dQi4. The control unit (120) can calculate the differential capacity ratio for the battery by calculating the formula “dQi4÷dQp4.”

[0113] In the embodiment of Fig. 7, the differential capacity of the fifth peak (p5) is dQp5, and the differential capacity of the fifth inflection point (i5) is dQi5. The control unit (120) can calculate the differential capacity ratio for the battery by calculating the formula “dQi5÷dQp5.”

[0114] The control unit (120) may be configured to calculate the mixing ratio of the first active material and the second active material included in the third battery based on the calculated differential capacity ratio.

[0115] Specifically, the control unit (120) can calculate the differential capacity ratio as the ratio of the first active material among the first and second active materials. For example, if the differential capacity ratio is 50%, the mixing ratio of the first and second active materials is 5:5. As another example, if the differential capacity ratio is 60%, the mixing ratio of the first and second active materials is 6:4.

[0116] The battery management device (100) can calculate the mixing ratio of the first active material and the second active material included in the battery by calculating the differential capacity ratio of the peak and inflection points. That is, since the battery management device (100) can non-destructively calculate the mixing ratio of multiple active materials through differential profile analysis, it has the advantage of effectively confirming and verifying the composition of the battery.

[0117]

[0118] The control unit (120) may be configured to set an upper limit voltage for the battery based on the determination result of the characteristic point. Here, the upper limit voltage is the maximum voltage set to terminate charging of the battery, and is a voltage set to prevent accelerated degradation of the battery.

[0119] In one embodiment, the control unit (120) may be configured to set the upper limit voltage to a preset voltage value corresponding to the type of battery when the determined characteristic point is one.

[0120] Specifically, the case where there is one feature point means that the feature point only contains a peak. In this case, the battery is a first battery containing a first active material or a second battery containing a second active material. Accordingly, the upper limit voltage of the battery may be set to a preset upper limit voltage for the type of active material contained in the battery. For example, if the battery is a first battery, the control unit (120) may set the upper limit voltage of the battery to 4.25 [V]. As another example, if the battery is a second battery, the control unit (120) may set the upper limit voltage of the battery to 4.35 [V].

[0121] In another embodiment, the control unit (120) may be configured to calculate a differential capacity ratio between multiple characteristic points when there are two determined characteristic points. Furthermore, the control unit (120) may be configured to set an upper voltage limit by adding the differential capacity ratio to preset voltage values ​​corresponding to a type of battery having one corresponding characteristic point.

[0122] As previously explained, the differential capacity ratio for the peak and inflection points may correspond to the mixing ratio of the first and second active materials contained in the battery. Accordingly, the control unit (120) can set the upper limit voltage of the battery by adding the calculated differential capacity ratio to the voltage set for the first active material and the voltage set for the second active material.

[0123] It is assumed that the voltage set for the first active material is Vs[V], the voltage set for the second active material is Vt[V], and the calculated differential capacity ratio is k%. Here, the relationship Vs[V] < Vt[V] is established. The control unit (120) can set the upper limit voltage of the battery by calculating the formula "Vt[V] - (Vt[V] - Vs[V])×k%".

[0124] For example, it is assumed that the voltage set for the first active material is 4.25 [V], the voltage set for the second active material is 4.35 [V], and the calculated differential capacity ratio is 60%. That is, the mixing ratio of the first active material and the second active material is 6:4. The control unit (120) can set the upper limit voltage of the battery to 4.29 [V] by calculating the formula “4.35-(4.35-4.25) × 0.6”. That is, as the mixing ratio of the first active material increases, the upper limit voltage can get closer to the voltage set for the first active material, and as the mixing ratio of the second active material increases, the upper limit voltage can get closer to the voltage set for the second active material.

[0125] The battery management device (100) can not only detect the composition of the battery, but also set an upper voltage limit optimized for the battery based on the composition. By setting an optimized upper voltage limit, the battery can be prevented from being overcharged, thereby extending its lifespan.

[0126]

[0127] The battery management device (100) according to the present invention can be applied to a BMS (Battery Management System). That is, the BMS according to the present invention can include the battery management device (100) described above. In this configuration, at least some of the components of the battery management device (100) can be implemented by supplementing or adding to the functions of the components included in a conventional BMS. For example, the profile acquisition unit (110) and the control unit (120) of the battery management device (100) can be implemented as components of the BMS.

[0128] Additionally, the battery management device (100) according to the present invention may be provided in a battery pack. That is, the battery pack according to the present invention may include the battery management device (100) described above and one or more battery cells. Additionally, the battery pack may further include electrical components (relays, fuses, etc.) and a case.

[0129] FIG. 8 is a schematic drawing of a battery pack (10) according to another embodiment of the present invention.

[0130] The positive terminal of the battery (11) can be connected to the positive terminal (P+) of the battery pack (10), and the negative terminal of the battery (11) can be connected to the negative terminal (P-) of the battery pack (10).

[0131] The measuring unit (12) can be connected to a first sensing line (SL1), a second sensing line (SL2), and a third sensing line (SL3). Specifically, the measuring unit (12) can be connected to a positive terminal of the battery (11) through the first sensing line (SL1), and can be connected to a negative terminal of the battery (11) through the second sensing line (SL2). The measuring unit (12) can measure the voltage of the battery (11) based on the voltage measured at each of the first sensing line (SL1) and the second sensing line (SL2).

[0132] And, the measuring unit (12) can be connected to the current measuring unit (A) through the third sensing line (SL3). For example, the current measuring unit (A) can be an ammeter or a shunt resistor capable of measuring the charging current and discharging current of the battery (11). The measuring unit (12) can measure the charging current of the battery (11) through the third sensing line (SL3) to calculate the charging amount. In addition, the measuring unit (12) can measure the discharging current of the battery (11) through the third sensing line (SL3) to calculate the discharging amount.

[0133] For example, the profile acquisition unit (110) can receive battery information about the voltage and current of the battery from the measurement unit (12). Then, the profile acquisition unit (110) can generate a battery profile (BP) and a differential profile based on the battery information.

[0134] As another example, the profile acquisition unit (110) can receive a battery profile (BP) from the measurement unit (12). Then, the profile acquisition unit (110) can generate a differential profile based on the battery profile (BP).

[0135] As another example, the profile acquisition unit (110) can receive a differential profile from the measurement unit (12).

[0136] An external device may be connected to the positive terminal (P+) and negative terminal (P-) of the battery pack (10). For example, the external device may be a charging device or a load. In addition, the positive terminal of the battery (11), the positive terminal (P+) of the battery pack (10), the external device, the negative terminal (P-) of the battery pack (10), and the negative terminal of the battery (11) may be electrically connected.

[0137]

[0138] A battery pack according to an embodiment of the present invention may be incorporated into an automobile, such as an electric vehicle (EV) or a hybrid vehicle (HV). Furthermore, the battery pack may power a motor via an inverter installed in the automobile, thereby driving the automobile. Here, the battery pack may include a battery management device (100). That is, the automobile may include the battery management device (100). In this case, the battery management device (100) may be an onboard device included in the automobile.

[0139]

[0140] FIG. 9 is a schematic diagram illustrating a battery management method according to another embodiment of the present invention.

[0141] Referring to FIG. 9, the battery management method may include a profile acquisition step (S100), a feature point determination step (S200), and a battery status determination step (S300).

[0142] Preferably, each step of the battery management method can be performed by a battery management device (100). In the following, for convenience of explanation, any content that overlaps with the previously described content will be omitted or briefly described.

[0143] The profile acquisition step (S100) is a step of acquiring a differential profile indicating a correspondence between the voltage and differential capacity of the battery, and can be performed by the profile acquisition unit (110).

[0144] For example, the profile acquisition unit (110) can directly receive the differential profile of the battery from the outside. That is, the profile acquisition unit (110) can acquire the differential profile by receiving the differential profile through a wired and / or wireless connection to the outside.

[0145] As another example, the profile acquisition unit (110) can directly receive the battery profile (BP) of the battery from the outside. Furthermore, the profile acquisition unit (110) can differentiate the battery profile (BP) with respect to voltage to generate a differential profile. That is, the profile acquisition unit (110) can be connected to the outside via wires and / or wirelessly to receive the battery profile (BP) and directly generate a differential profile from the battery profile (BP), thereby acquiring the differential profile.

[0146] As another example, the profile acquisition unit (110) may receive battery information regarding the voltage and capacity of the battery. Furthermore, the profile acquisition unit (110) may generate a battery profile (BP) based on the received battery information, and may generate a differential profile based on the generated battery profile (BP). In other words, the profile acquisition unit (110) may directly generate a differential profile based on the battery information, thereby acquiring the differential profile.

[0147] The feature point determination step (S200) is a step of determining a feature point included in a preset reference voltage section (R) of the differential profile, and can be performed by the control unit (120).

[0148] The control unit (120) can be configured to detect peaks and inflection points in the reference voltage section (R) of the differential profile, and determine the detected peaks and inflection points as feature points.

[0149] Specifically, the control unit (120) can detect a peak in the reference voltage section (R). Then, the control unit (120) can determine a target voltage section corresponding to a voltage higher than the peak in the reference voltage section (R). Thereafter, the control unit (120) can be configured to detect an inflection point in the target voltage section.

[0150] The battery status determination step (S300) is a step of determining the status of the battery based on the result of determining the characteristic point, and can be performed by the control unit (120).

[0151] Specifically, the control unit (120) can determine the state of the battery by determining the type of active material included in the battery based on the result of determining the characteristic point.

[0152] In addition, the control unit (120) can detect the composition of the battery and set an upper limit voltage optimized for the battery based on the composition of the battery.

[0153]

[0154] Another embodiment of the present invention can provide a computer-readable recording medium having recorded thereon a program for performing the various embodiments described above on a computer.

[0155] The program may be implemented as hardware components, software components, and / or a combination of hardware components and software components. The program may be executed by any system capable of executing computer-readable instructions.

[0156] Software may include computer programs, codes, instructions, or any combination thereof, which may configure a processing device to perform a desired operation or may independently or collectively command a processing device.

[0157] Software may be implemented as a computer program comprising instructions stored on a computer-readable storage medium. Examples of computer-readable storage media include magnetic storage media (e.g., read-only memory (ROM), random-access memory (RAM), floppy disks, hard disks, etc.) and optical reading media (e.g., CD-ROMs, Digital Versatile Discs (DVDs)). The computer-readable storage media may be distributed across network-connected computer systems, so that computer-readable code may be stored and executed in a distributed manner. The storage media may be readable by a computer, stored in a memory, and executed by a processor.

[0158] Computer-readable storage media may be provided in the form of non-transitory storage media. Here, the term "non-transitory storage media" simply means a tangible device that does not contain signals (e.g., electromagnetic waves). This term does not distinguish between cases where data is permanently stored on the storage media and cases where data is temporarily stored. For example, a "non-transitory storage medium" may include a buffer in which data is temporarily stored.

[0159] Additionally, the program may be provided as part of a computer program product. The computer program product may be traded as a commodity between sellers and buyers.

[0160] A computer program product may include a software program or a computer-readable storage medium storing the software program. For example, a computer program product may include a product in the form of a software program (e.g., a downloadable application) distributed electronically by an electronic device manufacturer or through an electronic marketplace. For electronic distribution, at least a portion of the software program may be stored on a storage medium or temporarily generated. In this case, the storage medium may be a storage medium of the electronic device manufacturer's server, an electronic marketplace server, or an intermediary server that temporarily stores the software program.

[0161] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical idea of ​​the present invention and the equivalent scope of the patent claims to be described below by a person having ordinary skill in the art to which the present invention pertains.

[0162] In addition, the present invention described above is not limited to the above-described embodiments and the attached drawings, and all or part of each embodiment may be selectively combined and configured so that various modifications can be made, as those skilled in the art can make various substitutions, modifications, and changes within the scope of the technical idea of ​​the present invention.

[0163] (Explanation of symbols)

[0164] 10: Battery pack

[0165] 11: Battery

[0166] 12: Measurement section

[0167] 100: Battery management device

[0168] 110: Profile acquisition section

[0169] 120: Control unit

[0170] 130: Storage

Claims

1. A profile acquisition unit configured to acquire a differential profile indicating a correspondence between the voltage and differential capacity of the battery; and A battery management device comprising a control unit configured to determine a characteristic point included in a preset reference voltage section of the above differential profile and determine a state of a battery based on a result of determining the characteristic point.

2. In paragraph 1, The above control unit, A battery management device configured to detect peaks and inflection points in the reference voltage section of the differential profile, and determine the detected peaks and inflection points as the feature points.

3. In paragraph 2, The above control unit, A battery management device configured to determine a target voltage section corresponding to a voltage higher than the peak voltage among the reference voltage sections, and to detect the inflection point in the target voltage section.

4. In paragraph 2, The above control unit, A battery management device configured to determine the battery as a first battery including a first active material or a second battery including a second active material when only the peak is detected as the above-mentioned characteristic point.

5. In paragraph 4, The above control unit, The above reference voltage section is divided into a first reference voltage section and a second reference voltage section, If the detected peak is included in the first reference voltage range, the battery is determined as the first battery, A battery management device configured to determine the battery as the second battery if the detected peak is included in the second reference voltage range.

6. In paragraph 2, The above control unit, A battery management device configured to determine the battery as a third battery including a first active material and a second active material when the peak and the inflection point are detected as the above-described characteristic points.

7. In paragraph 6, The above control unit, A battery management device configured to calculate a differential capacity ratio of the peak and the inflection point, and to calculate a mixing ratio of the first active material and the second active material included in the third battery based on the calculated differential capacity ratio.

8. In paragraph 1, The above control unit, A battery management device configured to set an upper limit voltage for the battery based on the determination result of the above characteristic point.

9. In paragraph 8, The above control unit, A battery management device configured to set the upper limit voltage to a preset voltage value corresponding to the type of the battery when the above-determined characteristic point is one.

10. In paragraph 8, The above control unit, If there are two feature points determined above, the differential capacity ratio between multiple feature points is calculated, A battery management device configured to set the upper limit voltage by adding the differential capacity ratio to preset voltage values ​​corresponding to a type of battery having one corresponding feature point.

11. A battery pack comprising a battery management device according to any one of claims 1 to 10.

12. A profile acquisition step for acquiring a differential profile representing the correspondence between the voltage and differential capacity of the battery; A feature point determination step for determining a feature point included in a preset reference voltage section of the above differential profile; and A battery management method comprising a battery status determination step of determining the status of a battery based on the determination result of the above characteristic points.

13. A profile acquisition step for acquiring a differential profile representing the correspondence between the voltage and differential capacity of the battery; A feature point determination step for determining a feature point included in a preset reference voltage section of the above differential profile; and A computer-readable recording medium storing a computer program for executing a battery management method including a battery state determination step of determining the state of the battery based on the determination result of the above characteristic points.

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