Battery diagnosis device and method

Abstract

A battery diagnosis device according to one embodiment of the present invention comprises: a voltage measurement unit for measuring voltages of a plurality of batteries; and a control unit for calculating a voltage deviation of the plurality of batteries, calculating a voltage deviation variance of each of the plurality of batteries, and diagnosing a state of each of the plurality of batteries based on the voltage deviation variance and a calculation period of the voltage deviation variance.

Description

Technical Field

[0001] This application claims priority to Korean Patent Application No. 10-2022-0172883 filed in Korea on December 12, 2022, the disclosure of which is incorporated herein by reference.

[0002] The present disclosure relates to a battery diagnosis device and method, and more particularly, to a battery diagnosis device and method capable of diagnosing an internal micro short circuit of a battery. Background Art

[0003] Recently, the demand for portable electronic products such as notebook computers, video cameras, and portable phones has increased dramatically, and electric vehicles, energy storage batteries, robots, satellites, etc. have been vigorously developed. Therefore, high-performance batteries that allow repeated charge and discharge are being actively studied.

[0004] Currently available batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, lithium batteries, etc. Among them, lithium batteries have attracted much attention because they have almost no memory effect compared to nickel-based batteries and also have a very low self-charging rate and high energy density.

[0005] An energy storage system using such a battery can be a device that stores large-scale electricity and provides the stored electricity to multiple load facilities. For example, the energy storage system is used in the form of an industrial, building or home energy management system and is used as a permanent power grid and / or emergency power grid by providing stored electricity to load facilities at each point of use.

[0006] If a micro short circuit occurs inside a battery, leakage current from the battery may occur. For example, assume that a plurality of batteries are included in a battery pack. If an internal micro short circuit occurs in any battery and leakage current occurs, the voltage of the battery may gradually decrease compared to the voltages of other batteries. Furthermore, if this phenomenon continues, a hard short circuit may occur, causing permanent damage to the battery pack.

[0007] Therefore, it is necessary to develop a technology that can diagnose in advance whether a micro short circuit has occurred inside the battery. Summary of the invention

[0008] Technical issues

[0009] The present disclosure is designed to solve the problems of the prior art, and thus the present disclosure aims to provide a battery diagnosis device and method, which can diagnose whether an internal micro short circuit occurs in a battery.

[0010] These and other objects and advantages of the present disclosure can be understood from the following detailed description and will be more fully apparent from the exemplary embodiments of the present disclosure.In addition, it can be easily understood that the objects and advantages of the present disclosure can be achieved by the means shown in the appended claims and their combinations.

[0011] Technical Solution

[0012] A battery diagnostic device according to one aspect of the present disclosure may include: a voltage measuring unit configured to measure the voltage of a plurality of batteries; and a control unit configured to calculate voltage deviations of the plurality of batteries, calculate a voltage deviation change of each of the plurality of batteries, and diagnose a state of each of the plurality of batteries based on the voltage deviation change and a calculation cycle of the voltage deviation change.

[0013] The control unit may be configured to determine a diagnosis score of each of the plurality of batteries according to the voltage deviation change amount and the calculation cycle based on a preset score table, and diagnose a state of each battery according to the accumulated diagnosis score of each of the plurality of batteries.

[0014] The control unit may be configured to determine a battery having a cumulative diagnosis score higher than or equal to a preset reference value among the plurality of batteries, and diagnose that an internal micro short circuit has occurred in the determined battery.

[0015] The control unit may be configured to determine a corresponding diagnosis score by substituting the voltage deviation change amount and the calculation period into the score table.

[0016] The control unit may be configured to determine the diagnosis score based on a first score table when the voltage deviation change amount is a positive number, and determine the diagnosis score based on a second score table when the voltage deviation change amount is a negative number or zero.

[0017] The first score table may be configured such that the higher the voltage deviation change amount and the shorter the calculation cycle, the higher the score is set.

[0018] The second score table may be configured such that the lower the voltage deviation change amount is and the shorter the calculation cycle is, the lower the score is set.

[0019] The control unit may be configured to calculate current voltage deviations of the plurality of batteries at a second time point after a predetermined period has elapsed from a first time point at which the voltage deviations are calculated, and calculate the voltage deviation change amount by calculating a difference between the voltage deviations and the current voltage deviations.

[0020] The control unit may be configured to calculate current voltage deviations of the plurality of batteries at a second time point after a predetermined period has elapsed from a first time point at which the voltage deviations are calculated, and calculate the calculation period by calculating a difference between the first time point and the second time point.

[0021] The control unit may be configured to calculate an average voltage of the plurality of batteries, and calculate a voltage deviation of each of the plurality of batteries by calculating a difference between the calculated average voltage and a voltage of each of the plurality of batteries.

[0022] A battery pack according to another aspect of the present disclosure may include the battery diagnosis device according to one aspect of the present disclosure.

[0023] A vehicle according to another aspect of the present disclosure may include the battery diagnosis device according to one aspect of the present disclosure.

[0024] According to another aspect of the present disclosure, a battery diagnosis method may include: a voltage measurement step, which measures the voltage of multiple batteries; a voltage deviation calculation step, which calculates the voltage deviation of the multiple batteries; a voltage deviation change calculation step, which calculates the voltage deviation change of each battery in the multiple batteries; and a diagnosis step, which diagnoses the state of each battery in the multiple batteries based on the voltage deviation change and the calculation period of the voltage deviation change.

[0025] Beneficial Effects

[0026] According to one aspect of the present disclosure, a battery diagnosis apparatus may diagnose the state of each battery by tracking a trend of a voltage deviation variation amount of the battery.

[0027] Furthermore, according to one aspect of the present disclosure, the state of the battery may be quantified in the form of a diagnostic score, and thus the state of the battery may be diagnosed on an objective basis.

[0028] The effects of the present disclosure are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the foregoing disclosure, are used to provide a further understanding of the technical features of the present disclosure. Therefore, the present disclosure is not to be construed as being limited to the accompanying drawings.

[0030] Figure 1 is a diagram schematically showing a battery diagnosis device according to an embodiment of the present disclosure.

[0031] Figure 2 is a diagram schematically illustrating voltages of a plurality of battery cells according to an embodiment of the present disclosure.

[0032] Figure 3 is a diagram schematically showing a voltage deviation change amount according to an embodiment of the present disclosure.

[0033] Figure 4is a diagram schematically showing a first score table according to an embodiment of the present disclosure.

[0034] Figure 5 is a diagram schematically showing a second score table according to an embodiment of the present disclosure.

[0035] Figure 6 is a diagram schematically illustrating a first diagnosis example according to an embodiment of the present disclosure.

[0036] Figure 7 is a diagram schematically illustrating a second diagnosis example according to an embodiment of the present disclosure.

[0037] Figure 8 is a diagram schematically showing an exemplary configuration of a battery pack according to another embodiment of the present disclosure.

[0038] Fig. 9 is a diagram schematically showing a vehicle according to another embodiment of the present disclosure.

[0039] Fig.10 is a diagram schematically illustrating a battery diagnosis method according to still another embodiment of the present disclosure. DETAILED DESCRIPTION

[0040] It should be understood that the terms used in the specification and the appended claims should not be interpreted as limited to the general meaning and dictionary meaning, but should be interpreted based on the meaning and concept corresponding to the technical aspects of the present disclosure on the basis of the principle allowing the inventor to appropriately define the terms for the best interpretation.

[0041] Therefore, the description presented herein is merely a preferred example for illustrative purposes, and is not intended to limit the scope of the present disclosure, and it should be appreciated that other equivalents and modifications may be proposed thereto without departing from the scope of the present disclosure.

[0042] Furthermore, in describing the present disclosure, when a detailed description of related known elements or functions is deemed to make the key subject matter of the present disclosure obscure, the detailed description is omitted herein.

[0043] Terms including ordinal numbers (for example, “first,” “second,” etc.) may be used to distinguish one element from another among various elements, but are not intended to limit the elements by the terms.

[0044] Throughout the specification, when a portion is referred to as “comprising” or “including” any element, it means that the portion may further include other elements without excluding other elements, unless specifically stated otherwise.

[0045] Furthermore, throughout the specification, when one part is referred to as being “connected” to another part, it is not limited to the case where the two are “directly connected” but also includes the case where the two are “indirectly connected” with another element interposed therebetween.

[0046] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0047] Figure 1 is a diagram schematically showing a battery diagnosis device 100 according to an embodiment of the present disclosure.

[0048] Reference Figure 1 The battery diagnosis device 100 may include a voltage measuring unit 110 and a control unit 120 .

[0049] Here, a battery refers to an independent cell having a negative terminal and a positive terminal and being physically separable. As an example, a lithium-ion cell or a lithium-polymer cell may be considered a battery. In the following, for ease of explanation, a battery is interpreted as meaning an independent cell.

[0050] The voltage measuring unit 110 may be configured to measure voltages of a plurality of batteries.

[0051] Specifically, the voltage measuring unit 110 may be configured to measure a voltage of each of the plurality of batteries.

[0052] Figure 2 is a diagram schematically illustrating voltages of a plurality of battery cells according to an embodiment of the present disclosure.

[0053] exist Figure 2 In the embodiment of the present invention, it is assumed that a first battery Ba, a second battery Bb, a third battery Bc, and a fourth battery Bd are provided. The voltage measuring unit 110 may measure the voltage of the first battery Ba as Va, the voltage of the second battery Bb as Vb, the voltage of the third battery Bc as Vc, and the voltage of the fourth battery Bd as Vd.

[0054] In addition, the voltage measuring unit 110 may be connected to enable communication with the control unit 120. For example, the voltage measuring unit 110 and the control unit 120 may be connected wiredly and / or wirelessly. The voltage measuring unit 110 may transmit information about the measured voltage to the control unit 120.

[0055] The control unit 120 may be configured to calculate voltage deviations of the plurality of batteries.

[0056] Specifically, the control unit 120 may receive voltage information of the plurality of batteries from the voltage measurement unit 110 and calculate voltage deviations of the plurality of batteries based on the received voltage information.

[0057] First, the control unit 120 may be configured to calculate an average voltage of the plurality of batteries. Figure 2 In the embodiment, the control unit 120 may calculate the average voltage of the voltages of the first to fourth batteries Ba, Bb, Bc, and Bd. For example, the control unit 120 may calculate the average voltage as Vavg by the calculation formula “(Va+Vb+Vc+Vd)÷4”.

[0058] Next, the control unit 120 may be configured to calculate a voltage deviation of each of the plurality of batteries by calculating a difference between the calculated average voltage and the voltage of each of the plurality of batteries. Figure 2 In an embodiment, the control unit 120 can calculate the voltage deviation of the first to fourth batteries Ba, Bb, Bc, Bd by calculating the difference between the voltage of the first to fourth batteries Ba, Bb, Bc, Bd and the average voltage. For example, the control unit 120 can calculate the voltage deviation of the first battery Ba as dVa by the calculation formula "|Va-Vavg|", and calculate the voltage deviation of the second battery Bb as dVb by the calculation formula "|Vb-Vavg|". In addition, the control unit 120 can calculate the voltage deviation of the third battery Bc as dVc by the calculation formula "|Vc-Vavg|", and can calculate the voltage deviation of the fourth battery Bd as dVd by the calculation formula "|Vd-Vavg|". Here, "||" is an absolute value symbol, and the calculated voltage deviation can be expressed as the absolute value of the difference between the battery voltage and the average voltage.

[0059] The control unit 120 may be configured to calculate a voltage deviation variation amount of each of the plurality of batteries.

[0060] Specifically, the control unit 120 may calculate the voltage deviation of each of the plurality of batteries. Here, the voltage deviation may be the voltage deviation of the plurality of batteries measured at the current time point. In addition, for each of the plurality of batteries, the control unit 120 may calculate the voltage deviation change amount between the voltage deviation calculated at the previous time point and the voltage deviation calculated at the current time point.

[0061] Figure 3 Schematically illustrates the voltage deviation variation according to an embodiment of the present disclosure. Specifically, Figure 3 The embodiment is a diagram showing only the voltage deviation of the first battery Ba among the voltage deviations of the first to fourth batteries Ba, Bb, Bc, Bd calculated at time points t0, t1, t2, and t3. Here, t0, t1, t2, and t3 may be time points at which the voltages of the first to fourth batteries Ba, Bb, Bc, Bd are measured.

[0062] In addition, Figure 3, only the voltage deviation of the first battery Ba is shown, but note that the voltage deviations of the second to fourth batteries Bb, Bc, Bd are also calculated to diagnose the states of the second to fourth batteries Bb, Bc, Bd.

[0063] exist Figure 3 In the embodiment, the voltage deviation of the first battery Ba calculated at the time point t0 is dV0, the voltage deviation of the first battery Ba calculated at the time point t1 is dV1, the voltage deviation of the first battery Ba calculated at the time point t2 is dV2, and the voltage deviation of the first battery Ba calculated at the time point t3 is dV3. The control unit 120 can calculate the voltage deviation change as △dV1 by calculating the difference between the voltage deviations at the time point t0 and the time point t1 according to the formula "dV1-dV0". The control unit 120 can calculate the voltage deviation change as △dV2 by calculating the difference between the voltage deviations at the time point t1 and the time point t2 according to the formula "dV2-dV1". The control unit 120 can calculate the voltage deviation change as △dV3 by calculating the difference between the voltage deviations at the time point t3 and the time point t2 according to the formula "dV3-dV2".

[0064] The control unit 120 may be configured to diagnose a state of each of the plurality of batteries based on the voltage deviation change amount and a calculation cycle of the voltage deviation change amount.

[0065] Specifically, the control unit 120 may be configured to calculate the current voltage deviations of the plurality of batteries at a second time point after a predetermined period has passed from a first time point at which the voltage deviations are calculated.

[0066] For example, in Figure 3 In the embodiment of the present invention, the time point t1 may be a time point after a predetermined period has passed since the time point t0. Here, assuming that the predetermined period is set to 10 days, the difference between the time point t0 and the time point t1 may be more than 10 days. Similarly, the time point t2 may be a time point after a predetermined period has passed since the time point t1. In addition, the time point t3 may be a time point after a predetermined period has passed since the time point t2.

[0067] exist Figure 3In the embodiment, if the time point t3 is a time point before the predetermined period from the time point t2 (for example, the difference between the time point t2 and the time point t3 is less than 10 days), the voltage deviation and the voltage deviation change amount may not be calculated at the time point t3. Assuming that the time point after the predetermined period from the time point t2 is the time point t4 (the time point after the time point t3), the control unit 120 may calculate the voltage deviation of the first battery Ba at the time point t4 as dV4. In addition, the control unit 120 may calculate the voltage deviation change amount at the time point t4 as △dV4 by calculating the difference between the voltage deviations at the time point t4 and the time point t2 according to the formula "dV4-dV2".

[0068] The control unit 120 may be configured to calculate the voltage deviation variation by calculating the difference between the voltage deviation and the current voltage deviation. In addition, the control unit 120 may be configured to calculate the calculation period by calculating the difference between the first time point and the second time point.

[0069] For example, in Figure 3 In the embodiment, the state of the first battery Ba can be diagnosed based on: 1) a first calculation cycle and △dV1 based on the difference between time point t0 and time point t1, 2) a second calculation cycle and △dV2 based on the difference between time point t1 and time point t2, and 3) a third calculation cycle and △dV3 based on the difference between time point t2 and time point t3.

[0070] The battery diagnosis device 100 according to the embodiment of the present disclosure can diagnose the state of a single battery by considering all voltage deviations of multiple batteries, the voltage deviation variation of a single battery, and the calculation cycle of the voltage deviation variation. In other words, the battery diagnosis device 100 can diagnose the state of each battery individually by tracking the trend of the voltage deviation variation of the battery.

[0071] In addition, the control unit 120 included in the battery diagnostic device 100 may optionally include a processor, an application specific integrated circuit (ASIC), other chipsets, logic circuits, registers, communication modems, data processing devices, etc., known in the art, to execute various control logics executed in the present disclosure. In addition, when the control logic is implemented as software, the control unit 120 may be implemented as a set of program modules. In this case, the program modules may be stored in a memory and executed by the control unit 120. The memory may be located inside or outside the control unit 120 and may be connected to the control unit 120 in various known ways.

[0072] In addition, the battery diagnostic device 100 may further include a storage unit 130. The storage unit 130 may store data required for the operation and function of each component of the battery diagnostic device 100, data generated in the process of performing an operation or function, and the like. The type of the storage unit 130 is not particularly limited as long as it is a known information storage device capable of recording, erasing, updating, and reading data. As an example, the information storage device may include a RAM, a flash memory, a ROM, an EEPROM, a register, and the like. In addition, the storage unit 130 may store a program code in which a process executable by the control unit 120 is defined.

[0073] For example, the storage unit 130 may be connected to communicate with the control unit 120. The storage unit 130 may store voltage information of the plurality of batteries measured by the voltage measuring unit 110. In addition, the storage unit 130 may store voltage deviations and voltage deviation variation amounts of the plurality of batteries calculated by the control unit 120 at each predetermined cycle.

[0074] The control unit 120 may be configured to determine a diagnosis score for each of the plurality of batteries according to the voltage deviation change amount and the calculation cycle based on a preset score table.

[0075] Here, the score table may be a table that sets the diagnosis score according to the score set in the voltage deviation change amount and the score set in the calculation cycle. Preferably, the score table may be configured to set a higher score as the voltage deviation increases (ie, as the voltage deviation change amount increases).

[0076] Specifically, the control unit 120 may be configured to determine the corresponding diagnostic score by substituting the voltage deviation change amount and the calculation cycle into the score table. That is, the control unit 120 may determine the diagnostic score corresponding to the current time point by substituting the voltage deviation change amount and the calculation cycle calculated at the current time point into the score table.

[0077] For example, in Figure 3 In an embodiment, the control unit 120 may determine the first diagnostic score by substituting the first calculation cycle according to the difference between the time point t0 and the time point t1 and △dV1 into the score table. In addition, the control unit 120 may determine the second diagnostic score by substituting the second calculation cycle according to the difference between the time point t1 and the time point t2 and △dV2 into the score table. In addition, the control unit 120 may determine the third diagnostic score by substituting the third calculation cycle according to the difference between the time point t2 and the time point t3 and △dV3 into the score table. In addition, the control unit 120 may diagnose the state of the first battery Ba based on at least one of the first diagnostic score, the second diagnostic score, and the third diagnostic score.

[0078] The control unit 120 may compare the determined diagnostic score with a preset reference value, and diagnose the state of the battery according to the comparison result. For example, if the determined diagnostic score is greater than or equal to the preset reference value, the control unit 120 may diagnose that an internal micro short circuit has occurred in the battery. On the contrary, if the determined diagnostic score is less than the preset reference value, the control unit 120 may diagnose the battery as normal.

[0079] The battery diagnostic device 100 according to the embodiment of the present disclosure can determine the diagnostic score of the battery using a preset score table. In addition, since the battery diagnostic device 100 diagnoses the state of the battery according to the determined diagnostic score, it has the advantage of being able to quickly diagnose the states of multiple batteries using the same standard.

[0080] The control unit 120 may be configured to diagnose a state of each battery according to a cumulative diagnosis score of each battery among the plurality of batteries.

[0081] Specifically, the control unit 120 may diagnose the state of the battery not only based on the diagnosis score determined at any one time point, but may diagnose the state of the battery based on the sum of the diagnosis scores determined at multiple time points (cumulative diagnosis score).

[0082] For example, due to voltage measurement noise or communication noise, the diagnostic score determined at a certain time point may contain errors. If the state of the battery is diagnosed based on the diagnostic score containing errors, there is a problem that the state of the battery may be misdiagnosed. Therefore, the control unit 120 can diagnose the state of the battery based on the cumulative diagnostic score.

[0083] Preferably, the control unit 120 may be configured to determine a battery having a cumulative diagnosis score greater than or equal to a preset reference value among the plurality of batteries.

[0084] For example, the reference value may be preset to 20 points. The control unit 120 may calculate a cumulative diagnostic score by adding all diagnostic scores at multiple time points. In addition, the control unit 120 may diagnose the state of the battery by comparing the calculated cumulative diagnostic score with a preset reference value.

[0085] Preferably, in order to diagnose the state of the battery based on the cumulative diagnosis score, the reference value may be preset to a value greater than the maximum value set in the score table. For example, if the maximum value set in the score table is 16, the reference value may be set to 20.

[0086] Furthermore, the control unit 120 may be configured to diagnose that an internal micro short circuit has occurred in the determined battery. In contrast, if the determined cumulative diagnosis score is less than a preset reference value, the control unit 120 may diagnose the battery as normal.

[0087] For example, the voltage deviation of a battery having an internal micro short circuit may gradually increase over time relative to other batteries. Therefore, since a battery having a cumulative diagnostic score greater than or equal to the reference value is a battery whose voltage deviation gradually increases compared to other batteries, the control unit 120 can diagnose that an internal micro short circuit has occurred in the battery.

[0088] The battery diagnostic apparatus 100 according to an embodiment of the present disclosure may more accurately diagnose the state of the battery by diagnosing the state of the battery based on the accumulated diagnostic scores at a plurality of time points.

[0089] In one embodiment, the score table may include a first score table T1 and a second score table T2. Here, the first score table T1 may be a score table used when the voltage deviation change is a positive number, and the second score table T2 may be a score table used when the voltage deviation change is a negative number or 0.

[0090] The control unit 120 may be configured to determine the diagnosis score based on the first score table T1 when the voltage deviation change amount is a positive number.

[0091] If the voltage deviation change is a positive number, it may indicate that the voltage deviation of the battery is gradually increasing. In addition, if the voltage deviation change is large despite a short calculation cycle, it may indicate that the state of the battery is rapidly deteriorating. Therefore, when the voltage deviation change is a positive number, the score corresponding to the voltage deviation change may be set to a positive number so that the cumulative diagnostic score may increase. In other words, the first score table T1 may be configured such that the higher the voltage deviation change and the shorter the calculation cycle, the higher the score is set.

[0092] Figure 4 Schematically shows a first score table T1 according to an embodiment of the present disclosure. Note that Figure 4 The calculation period portion, the voltage deviation change amount portion, and the score included in the embodiments are examples, and the values ​​may be changed.

[0093] exist Figure 4 In the implementation manner, if the calculation period is more than 10 days and less than 20 days, it can be set to 4 points, if the calculation period is more than 20 days and less than 30 days, it can be set to 3 points, if the calculation period is more than 30 days and less than 40 days, it can be set to 2 points, and if the calculation period is more than 40 days, it can be set to 1 point. In addition, if the voltage deviation change is greater than 0 and less than 3, it can be set to 1 point; if the voltage deviation change is greater than 3 and less than 6, it can be set to 2 points; if the voltage deviation change is greater than 6 and less than 9, it can be set to 3 points; and if the voltage deviation change is greater than 9, it can be set to 4 points.

[0094] The control unit 120 may be configured to determine the diagnosis score based on the second score table T2 when the voltage deviation change amount is a negative number or zero.

[0095] If the voltage deviation change is negative or 0, it can indicate that the voltage deviation of the battery has not increased. In addition, even if the calculation cycle is short, if the voltage deviation change is small (in other words, if the absolute value of the voltage deviation change is large), it can also indicate that the state of the battery is rapidly normalizing. Therefore, when the voltage deviation change is negative or 0, the score corresponding to the voltage deviation change can be set to a negative number, so that the cumulative diagnostic score can be reduced. In other words, the second score table T2 can be configured to set a lower score as the voltage deviation change is smaller and the calculation cycle is shorter.

[0096] Figure 5 Schematically shows a second score table T2 according to an embodiment of the present disclosure. Note that Figure 5 The calculation period portion, the voltage deviation change amount portion, and the score included in the embodiments are examples, and the values ​​may be changed.

[0097] exist Figure 5 In the implementation manner, if the calculation period is more than 10 days and less than 20 days, it can be set to 4 points, if the calculation period is more than 20 days and less than 30 days, it can be set to 3 points, if the calculation period is more than 30 days and less than 40 days, it can be set to 2 points, and if the calculation period is more than 40 days, it can be set to 1 point. In addition, if the voltage deviation change is less than 0 and greater than -1, it can be set to -1 points; if the voltage deviation change is less than -1 and greater than -2, it can be set to -2 points; if the voltage deviation change is less than -2 and greater than -3, it can be set to -3 points; and if the voltage deviation change is less than -3, it can be set to -4 points.

[0098] The cumulative diagnostic score can be increased or decreased according to the calculated voltage deviation change. In other words, the change trend of the battery state can be scored and expressed in the form of a cumulative diagnostic score. Therefore, the battery diagnostic device 100 has the advantage of quantifying the battery state and expressing it as an objective indicator.

[0099] In the following, reference will be made to Figure 6 and Figure 7 A specific diagnosis example is described. As in the previous embodiment, it is assumed that the reference value is preset to 20 points.

[0100] Figure 6 is a diagram schematically illustrating a first diagnosis example according to an embodiment of the present disclosure.

[0101] exist Figure 6In the implementation manner, it is assumed that the first calculation period (d1) as the difference between time point t0 and time point t1, the second calculation period (d2) as the difference between time point t1 and time point t2, and the third calculation period (d3) as the difference between time point t2 and time point t3 are set to a predetermined period of 10 days.

[0102] The first calculation period (d1) at time point t1 may be 10 days, and the first voltage deviation change (ΔdV1) may be 4. Since the first voltage deviation change (ΔdV1) is a positive number, the control unit 120 may determine the diagnosis score at time point t1 according to the first score table T1. Figure 4 , since the first calculation period (d1) is 10 days, the score of the calculation period is 4 points, and since the first voltage deviation change (ΔdV1) is 4, the score of the voltage deviation change is 2 points. Therefore, the control unit 120 can determine the diagnosis score at time point t1 as 8 points.

[0103] The control unit 120 may determine the cumulative diagnosis score at time point t1 to be 8 points.

[0104] The second calculation period (d2) at time point t2 may be 10 days, and the second voltage deviation change (ΔdV2) may be -2. Since the second voltage deviation change (ΔdV2) is a negative number, the control unit 120 may determine the diagnosis score at time point t2 according to the second score table T2. Figure 5 , since the first calculation period (d1) is 10 days, the score of the calculation period is 4 points, and since the second voltage deviation change (ΔdV2) is -2, the score of the voltage deviation change is -3 points. Therefore, the control unit 120 can determine the diagnosis score at time point t2 as -12 points.

[0105] The control unit 120 can determine the cumulative diagnosis score at time point t2 as -4 points by calculating formula "8-12".

[0106] The third calculation period (d3) at time point t3 may be 10 days, and the third voltage deviation change amount (ΔdV3) may be 6. Since the third voltage deviation change amount (ΔdV3) is a positive number, the control unit 120 may determine the diagnosis score at time point t3 according to the first score table T1. Figure 4 , since the third calculation period (d3) is 10 days, the score of the calculation period is 4 points, and since the third voltage deviation change (ΔdV3) is 6, the score of the voltage deviation change is 2 points. Therefore, the control unit 120 can determine the diagnosis score at time point t3 as 8 points.

[0107] The control unit 120 may determine the cumulative diagnosis score at time point t3 to be 4 points by using the calculation formula “8-12+8”.

[0108] Therefore, the control unit 120 can Figure 6 The embodiment diagnoses the state of the battery as a normal state.

[0109] Figure 7 is a diagram schematically illustrating a second diagnosis example according to an embodiment of the present disclosure.

[0110] exist Figure 7 In the embodiment of the present invention, it is assumed that the first calculation period (d1) as the difference between the time point t0 and the time point t1 and the third calculation period (d3) as the difference between the time point t2 and the time point t3 are set to 10 days as a predetermined period. In addition, it is assumed that the second calculation period (d2) as the difference between the time point t1 and the time point t2 is 20 days.

[0111] The first calculation period (d1) at time point t1 may be 10 days, and the first voltage deviation change (ΔdV1) may be 4. Since the first voltage deviation change (ΔdV1) is a positive number, the control unit 120 may determine the diagnosis score at time point t1 according to the first score table T1. Figure 4 , since the first calculation period (d1) is 10 days, the score of the calculation period is 4 points, and since the first voltage deviation change (ΔdV1) is 4, the score of the voltage deviation change is 2 points. Therefore, the control unit 120 can determine the diagnosis score at time point t1 as 8 points.

[0112] The control unit 120 may determine the cumulative diagnosis score at time point t1 to be 8 points.

[0113] The second calculation period (d2) at time point t2 may be 20 days, and the second voltage deviation change (ΔdV2) may be 3. Since the second voltage deviation change (ΔdV2) is a positive number, the control unit 120 may determine the diagnosis score at time point t2 according to the first score table T1. Figure 4 , since the second calculation period (d2) is 20 days, the score of the calculation period is 3 points, and since the second voltage deviation change (ΔdV2) is 3, the score of the voltage deviation change is 1 point. Therefore, the control unit 120 can determine the diagnosis score at time point t2 as 3 points.

[0114] The control unit 120 can determine the cumulative diagnosis score at time point t2 to be 11 points by using the calculation formula “8+3”.

[0115] The third calculation period (d3) at time point t3 may be 10 days, and the third voltage deviation change amount (ΔdV3) may be 7. Since the third voltage deviation change amount (ΔdV3) is a positive number, the control unit 120 may determine the diagnosis score at time point t3 according to the first score table T1. Figure 4 , since the third calculation period (d3) is 10 days, the score of the calculation period is 4 points, and since the third voltage deviation change (ΔdV3) is 7, the score of the voltage deviation change is 3 points. Therefore, the control unit 120 can determine the diagnosis score at time point t3 as 12 points.

[0116] The control unit 120 can determine the cumulative diagnosis score at time point t3 to be 23 points by using the calculation formula “8+3+12”.

[0117] Since the cumulative diagnosis score (23 points) at time point t3 exceeds the reference value (20 points), the control unit 120 can Figure 7 The embodiment diagnoses that an internal micro short circuit has occurred in the battery.

[0118] Furthermore, the control unit 120 may compare relative states between the plurality of batteries based on the cumulative diagnosis scores of the plurality of batteries.

[0119] Specifically, the cumulative diagnosis score may be an index for quantifying the state of the battery. Therefore, the control unit 120 may compare the relative states between the plurality of batteries by comparing the cumulative diagnosis scores.

[0120] For example, when the cumulative diagnostic score is low, the relative status may be a normal status. Figure 2 In the embodiment of FIG. 1 , it is assumed that the cumulative diagnostic score of the first battery Ba is 10 points, the cumulative diagnostic score of the second battery Bb is 15 points, the cumulative diagnostic score of the third battery Bc is 7 points, and the cumulative diagnostic score of the fourth battery Bd is 19 points. In this case, the control unit 120 may determine that the third battery Bc is in the most relatively normal state, and the fourth battery Bd is in the most relatively abnormal state.

[0121] The battery diagnostic device 100 according to the present disclosure may be applied to a battery management system (BMS). That is, the BMS according to the present disclosure may include the above-mentioned battery diagnostic device 100. In this configuration, at least some components of the battery diagnostic device 100 may be implemented by supplementing or adding functions of components included in a conventional BMS. For example, the voltage measuring unit 110, the control unit 120, and the storage unit 130 of the battery diagnostic device 100 may be implemented as components of the BMS.

[0122] In addition, the battery diagnostic device 100 according to the present disclosure may be provided in the battery pack 10. That is, the battery pack 10 according to the present disclosure may include the battery diagnostic device 100 and at least one battery cell. In addition, the battery pack 10 may further include electrical components (relays, fuses, etc.) and a housing.

[0123] Figure 8 2 is a diagram schematically showing an exemplary configuration of a battery pack 10 according to another embodiment of the present disclosure. Preferably, the battery pack 10 may include a battery diagnosis device 100 .

[0124] The battery pack 10 may include a first battery Ba, a second battery Bb, a third battery Bc, and a fourth battery Bd. Figure 8 In the embodiment of the present invention, the first battery Ba, the second battery Bb, the third battery Bc and the fourth battery Bd may be connected in series. Note that the number of batteries included in the battery pack 10 and the connection relationship of the batteries (series and / or parallel) are not affected by Figure 8 limitations on the implementation methods.

[0125] The positive terminal of the first battery Ba may be connected to the positive terminal P+ of the battery pack 10 , and the negative terminal of the fourth battery Bd may be connected to the negative terminal P− of the battery pack 10 .

[0126] The voltage measuring unit 110 may be connected to the first, second, third, fourth, and fifth sensing lines SL1, SL2, SL3, SL4, and SL5.

[0127] Specifically, the voltage measuring unit 110 may be connected to the positive terminal of the first battery Ba through the first sensing line SL1, and may be connected to the negative terminal of the first battery Ba through the second sensing line SL2. The voltage measuring unit 110 may measure the voltage of the first battery Ba based on the voltage measured at each of the first sensing line SL1 and the second sensing line SL2.

[0128] Similarly, the voltage measuring unit 110 can measure the voltage of the second battery Bb through the second sensing line SL2 and the third sensing line SL3, measure the voltage of the third battery Bc through the third sensing line SL3 and the fourth sensing line SL4, and measure the voltage of the fourth battery Bd through the fourth sensing line SL4 and the fifth sensing line SL5.

[0129] The external device may be connected to the positive terminal P+ and the negative terminal P- of the battery pack 10. For example, the external device may be a motor of an electric vehicle that receives power from the battery pack 10. As another example, the external device may be a charging device for charging the battery pack 10.

[0130] Fig. 9is a diagram schematically showing a vehicle 900 according to another embodiment of the present disclosure.

[0131] Reference Fig. 9 The battery pack 910 according to the embodiment of the present disclosure may be included in a vehicle 900 such as an electric vehicle (EV) or a hybrid vehicle (HV). In addition, the battery pack 910 may drive the vehicle 900 by supplying power to a motor through an inverter provided in the vehicle 900. In addition, the battery pack 910 may include the battery diagnostic device 100 according to the embodiment of the present disclosure.

[0132] Fig.10 is a diagram schematically illustrating a battery diagnosis method according to still another embodiment of the present disclosure.

[0133] Preferably, each step of the battery diagnosis method may be performed by the battery diagnosis apparatus 100. Hereinafter, for the convenience of explanation, contents repeated with the previously described contents will be briefly described or omitted.

[0134] The voltage measuring step ( S100 ) is a step of measuring voltages of a plurality of batteries and may be performed by the voltage measuring unit 110 .

[0135] For example, the voltage measurement unit 110 may measure the voltage of each of the plurality of batteries.

[0136] exist Figure 2 In the embodiment of the present invention, the voltage measuring unit 110 may measure the voltages of the first battery Ba, the second battery Bb, the third battery Bc, and the fourth battery Bd as Va, Vb, Vc, and Vd.

[0137] The voltage deviation calculation step ( S200 ) is a step for calculating voltage deviations of a plurality of batteries, and may be performed by the control unit 120 .

[0138] For example, the control unit 120 may calculate an average voltage of the plurality of batteries. In addition, the control unit 120 may calculate a voltage deviation of each of the plurality of batteries by calculating a difference between the calculated average voltage and a voltage of each of the plurality of batteries.

[0139] exist Figure 2 In the embodiment, the control unit 120 may calculate the average voltage of the first battery Ba, the second battery Bb, the third battery Bc, and the fourth battery Bd as Vavg. The control unit 120 may calculate the voltage deviations of the first battery Ba, the second battery Bb, the third battery Bc, and the fourth battery Bd as dVa, dVb, dVc, and dVd by calculating the differences between the voltages of the first battery Ba, the second battery Bb, the third battery Bc, and the fourth battery Bd and the average voltage.

[0140] The voltage deviation change amount calculation step ( S300 ) is a step for calculating the voltage deviation change amount of each of the plurality of batteries, and may be performed by the control unit 120 .

[0141] For example, for each of the plurality of batteries, the control unit 120 may calculate a voltage deviation change amount between a voltage deviation calculated at a previous time point and a voltage deviation calculated at a current time point.

[0142] Preferably, the difference between the previous time point and the current time point may be more than a predetermined period. For example, if the predetermined period is set to 10 days, the previous time point and the current time point may differ by more than 10 days.

[0143] The diagnosis step ( S400 ) is a step of diagnosing the state of each of the plurality of batteries based on the voltage deviation change amount and the calculation cycle of the voltage deviation change amount, and may be performed by the control unit 120 .

[0144] For example, the control unit 120 may be configured to determine the diagnostic score of each of the multiple batteries according to the voltage deviation change amount and the calculation cycle based on a preset score table. Preferably, the control unit 120 may be configured to diagnose the state of each battery according to the cumulative diagnostic score of each of the multiple batteries. If the cumulative diagnostic score is higher than or equal to a preset reference value, the control unit 120 may diagnose that an internal micro short circuit has occurred in the battery. On the contrary, if the cumulative diagnostic score is less than the preset reference value, the control unit 120 may diagnose the battery as normal.

[0145] The embodiments of the present disclosure described above can be implemented not only by devices and methods, but also by programs that implement functions corresponding to the configurations of the embodiments of the present disclosure or recording media having the programs recorded thereon. According to the description of the embodiments described above, those skilled in the art can easily implement the programs or recording media.

[0146] The present disclosure has been described in detail. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the present disclosure, are given by way of illustration only, as various changes and modifications within the scope of the present disclosure will become apparent to those skilled in the art from this detailed description.

[0147] In addition, without departing from the technical aspects of the present disclosure, those skilled in the art may make many substitutions, modifications and changes to the present disclosure described above, and the present disclosure is not limited to the above-mentioned embodiments and drawings, and each embodiment may be selectively combined in part or in whole to allow various variations.

[0148] (Explanation of Reference Numerals)

[0149] 10: Battery Pack

[0150] 100: Battery diagnostic device

[0151] 110: Voltage measurement unit

[0152] 120: Control unit

[0153] 130: Storage unit

[0154] 900: Vehicles

[0155] 910: Battery Pack

[0156] Ba: First Battery

[0157] Bb: Second battery

[0158] Bc: Third battery

[0159] Bd: Fourth battery

Claims

1. A battery diagnostic device, comprising: a voltage measuring unit configured to measure voltages of a plurality of batteries; as well as A control unit is configured to calculate voltage deviations of the plurality of batteries, calculate a voltage deviation change amount of each of the plurality of batteries, and diagnose a state of each of the plurality of batteries based on the voltage deviation change amount and a calculation cycle of the voltage deviation change amount.

2. The battery diagnostic device according to claim 1, in, The control unit is configured to determine a diagnosis score of each of the plurality of batteries according to the voltage deviation change amount and the calculation cycle based on a preset score table, and diagnose a state of each of the plurality of batteries according to a cumulative diagnosis score of each of the plurality of batteries.

3. The battery diagnostic device according to claim 2, in, The control unit is configured to determine a battery whose cumulative diagnosis score is higher than or equal to a preset reference value among the plurality of batteries, and diagnose that an internal micro short circuit has occurred in the determined battery.

4. The battery diagnosis device according to claim 2, in, The control unit is configured to determine a corresponding diagnosis score by substituting the voltage deviation change amount and the calculation period into the score table.

5. The battery diagnosis device according to claim 2, in, The control unit is configured to determine the diagnosis score based on a first score table when the voltage deviation change amount is a positive number, and to determine the diagnosis score based on a second score table when the voltage deviation change amount is a negative number or zero.

6. The battery diagnosis device according to claim 5, in, The first score table is configured such that the higher the voltage deviation change amount is and the shorter the calculation cycle is, the higher the score is set.

7. The battery diagnosis device according to claim 5, in, The second score table is configured such that the lower the voltage deviation change amount is and the shorter the calculation cycle is, the lower the score is set.

8. The battery diagnostic device according to claim 1, in, The control unit is configured to calculate current voltage deviations of the plurality of batteries at a second time point after a predetermined period has passed from a first time point at which the voltage deviations are calculated, and calculate the voltage deviation change amount by calculating a difference between the voltage deviations and the current voltage deviations.

9. The battery diagnostic device according to claim 1, in, The control unit is configured to calculate current voltage deviations of the plurality of batteries at a second time point after a predetermined period has passed from a first time point at which the voltage deviations are calculated, and calculate the calculation period by calculating a difference between the first time point and the second time point.

10. The battery diagnosis device according to claim 1, in, The control unit is configured to calculate an average voltage of the plurality of batteries, and calculate a voltage deviation of each of the plurality of batteries by calculating a difference between the calculated average voltage and a voltage of each of the plurality of batteries. 11 . A battery pack, comprising the battery diagnosis device according to claim 1 . 12 . A vehicle comprising the battery diagnosis device according to claim 1 .

13. A battery diagnosis method, the battery diagnosis method comprising: a voltage measuring step, wherein the voltage measuring step measures the voltage of a plurality of batteries; a voltage deviation calculating step, wherein the voltage deviation calculating step calculates the voltage deviation of the plurality of batteries; a voltage deviation variation calculation step, wherein the voltage deviation variation calculation step calculates the voltage deviation variation of each battery in the plurality of batteries; as well as a diagnosing step of diagnosing a state of each of the plurality of batteries based on the voltage deviation change amount and a calculation cycle of the voltage deviation change amount.

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