Battery diagnostic device and method
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-13
- Publication Date
- 2026-08-11
Smart Images
Figure CN122555858A_ABST
Abstract
Description
Technical Field
[0001] This application is based on and claims priority to Korean Patent Application No. 10-2024-0168345, filed with the Korean Intellectual Property Office on November 22, 2024, the disclosure of which is incorporated herein by reference in its entirety.
[0002] This disclosure relates to a battery diagnostic apparatus and method for diagnosing the state of a battery. Background Technology
[0003] Recently, demand for portable electronic products such as laptops, cameras, and mobile phones has increased dramatically, and electric vehicles, energy storage batteries, robots, and satellites have seen significant development. Therefore, high-performance batteries that allow for repeated charging and discharging are being actively researched.
[0004] Currently available batteries include nickel-cadmium (NiCd), nickel-metal hydride (NiMH), nickel-zinc (NiZn), and lithium-ion batteries. Among them, lithium-ion batteries have attracted much attention due to their virtually non-existent memory effect compared to nickel-based batteries, as well as their very low self-discharge rate and high energy density.
[0005] While extensive research is underway to increase the capacity and density of these batteries, improving their lifespan and safety is also crucial. To enhance battery safety, technologies for accurately diagnosing the state of the battery are needed. Summary of the Invention
[0006] Technical issues
[0007] This disclosure aims to provide a battery diagnostic apparatus and method for more accurately estimating the current state of a battery.
[0008] These and other objects and advantages of this disclosure will become apparent from the following detailed description and from exemplary embodiments thereof. Furthermore, it will be readily understood that the objects and advantages of this disclosure can be achieved by the means shown in the appended claims and combinations thereof.
[0009] Technical solution
[0010] A battery diagnostic apparatus according to one aspect of the present disclosure may include: a curve acquisition unit configured to acquire a voltage curve of a battery voltage measured according to a preset measurement cycle; and a control unit configured to determine a first voltage range and a second voltage range from a plurality of voltage curves acquired by the curve acquisition unit in a plurality of cycles, determine a first number of voltages contained in the first voltage range and a second number of voltages contained in the second voltage range in each of the plurality of voltage curves, and diagnose the state of the battery based on a first ratio of the plurality of first voltages and a second ratio of the plurality of second voltages.
[0011] The control unit can be configured to compare a first ratio with a second ratio and diagnose the battery state as normal, warning, or abnormal based on the comparison result.
[0012] The control unit can be configured to diagnose the battery state as normal when the first ratio is greater than the second ratio.
[0013] When the first ratio is less than or equal to the second ratio, the control unit can be configured to compare the first rate of change of the first ratio and the second rate of change of the second ratio with a preset reference rate of change, and diagnose the battery state as a warning state or an abnormal state based on the comparison result.
[0014] The control unit can be configured to diagnose the battery state as a warning state when the first rate of change and the second rate of change are less than or equal to the reference rate of change.
[0015] The control unit can be configured to diagnose the battery state as abnormal when the first rate of change and the second rate of change exceed the reference rate of change.
[0016] The control unit can be configured to set a reference voltage range in multiple voltage curves and divide the reference voltage range into a first voltage range and a second voltage range.
[0017] The control unit can be configured to divide the reference voltage range into a low voltage range and a high voltage range, with the low voltage range designated as the first voltage range and the high voltage range designated as the second voltage range.
[0018] The control unit can be configured to exclude voltage curves from the state of the diagnostic battery that do not include at least a portion of the reference voltage range among multiple voltage curves.
[0019] The control unit can be configured to set a preset voltage range or a common voltage range of multiple voltage curves as a reference voltage range.
[0020] The control unit can be configured to set the common voltage range as the reference voltage range when there is a common voltage range of multiple voltage curves.
[0021] The control unit can be configured to set a preset voltage range as a reference voltage range when no common voltage range exists.
[0022] The control unit can be configured to calculate a first ratio of each of a plurality of first voltage quantities based on a first reference quantity, and to calculate a second ratio of each of a plurality of second voltage quantities based on a second reference quantity.
[0023] The control unit can be configured to set a first voltage number of the initial cycle in a plurality of cycles as a first reference number, and set a second voltage number of the initial cycle as a second reference number.
[0024] The control unit can be configured to diagnose the battery status based on a cycle that is greater than or equal to a preset reference cycle among multiple cycles.
[0025] According to another aspect of this disclosure, a battery pack includes a battery diagnostic device according to one aspect of this disclosure.
[0026] A battery diagnostic method according to another aspect of this disclosure may include: a curve acquisition step, acquiring a voltage curve of the battery voltage measured according to a preset measurement cycle; a voltage range determination step, determining a first voltage range and a second voltage range from a plurality of voltage curves acquired in the curve acquisition step; a voltage quantity determination step, determining a first voltage quantity of voltages included in the first voltage range and a second voltage quantity of voltages included in the second voltage range in each of the plurality of voltage curves; and a diagnostic step, diagnosing the state of the battery based on a first ratio of the plurality of first voltage quantities and a second ratio of the plurality of second voltage quantities.
[0027] According to another aspect of this disclosure, a computer-readable recording medium may store a computer program for performing a battery diagnostic method according to one aspect of this disclosure.
[0028] Beneficial effects
[0029] According to one aspect of this disclosure, a battery diagnostic device can diagnose the state of a battery by taking into account the variation patterns of the number of voltages measured within a predetermined voltage range, while also considering changes in battery state or performance.
[0030] Furthermore, according to the battery diagnostic device, since variation pattern analysis is relatively easy, battery diagnostics can be performed quickly, and the system resources required for battery diagnostics can be saved. Additionally, because it employs a method of counting the number of measured voltages, it has the advantage of being more robust to noise compared to methods that diagnose battery status using measured voltage values.
[0031] The effects of this disclosure are not limited to those mentioned above, and those skilled in the art will clearly understand other effects not mentioned in the claims. Attached Figure Description
[0032] The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the foregoing disclosure, are intended to provide a further understanding of the technical features of the present disclosure; therefore, the present disclosure should not be construed as limited to the drawings.
[0033] Figure 1This is a schematic diagram illustrating a battery diagnostic apparatus according to an embodiment of the present disclosure.
[0034] Figure 2 This is a schematic diagram illustrating voltage curves according to embodiments of the present disclosure.
[0035] Figures 3 to 6 It is a diagram schematically showing the first and second ratios for each cycle of the first through fourth cells.
[0036] Figure 7 This is a schematic diagram illustrating a battery pack according to another embodiment of the present disclosure.
[0037] Figure 8 This is a schematic diagram illustrating a battery diagnostic method according to yet another embodiment of the present disclosure. Detailed Implementation
[0038] Before the description, it should be understood that the terms used in the specification and appended claims should not be construed as limited to their general or dictionary meanings, but rather should be interpreted based on their meanings and concepts corresponding to the technical aspects of this disclosure, on the basis of the principle that the inventors are allowed to define the terms appropriately for the best interpretation.
[0039] Therefore, the description presented herein is merely the best example for illustrative purposes and is not intended to limit the scope of this disclosure. It should be understood that other equivalents and modifications may be made thereto without departing from the scope of this disclosure.
[0040] Furthermore, in interpreting this disclosure, if a detailed description of a relevant known structure or function is deemed likely to obscure the essential points of this disclosure, such detailed description will be omitted.
[0041] Ordinal terms such as “first” and “second” can be used to distinguish one element from another among various elements, but are not intended to limit these elements.
[0042] Throughout this specification, when a part is referred to as “including” or “containing” any element, it means that the part may further include other elements, rather than excluding other elements, unless otherwise expressly stated.
[0043] Furthermore, throughout the instruction manual, when a part is referred to as being “connected” to another part, it is not limited to the case where they are “directly connected,” but also includes the case where they are “indirectly connected” when another element is inserted between them.
[0044] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.
[0045] Figure 1This is a schematic diagram illustrating a battery diagnostic device 100 according to an embodiment of the present disclosure.
[0046] refer to Figure 1 The battery diagnostic device 100 may include a curve acquisition unit 110 and a control unit 120.
[0047] Here, a battery refers to a physically separable, individual cell with a negative and a positive terminal. For example, a lithium-ion cell or a lithium polymer cell can be considered a battery. Furthermore, batteries can be cylindrical, prismatic, or pouch-shaped. Additionally, a battery can also refer to a battery bank, battery module, or battery pack containing multiple cells connected in series and / or parallel. For clarity, in the following description, a battery refers to a single, independent cell.
[0048] The curve acquisition unit 110 can be configured to acquire a voltage curve of the battery voltage measured according to a preset measurement cycle.
[0049] Specifically, the battery voltage can be measured according to a preset measurement cycle. Then, a voltage curve representing voltage changes over time or voltage changes based on capacity can be generated.
[0050] For example, during the charging process, the battery voltage can be measured every 0.1 seconds. In this case, a voltage curve can be generated representing the voltage measured at each measurement point at 0.1-second intervals during the battery charging process.
[0051] Figure 2 This is a schematic diagram illustrating voltage curves according to embodiments of the present disclosure. Figure 2 In some embodiments, the voltage curve can be represented as an XY graph, where the X-axis is set to time and the Y-axis is set to voltage. However, it should be noted that... Figure 2 The voltage curve is presented in graphical form for ease of explanation only, and there are no restrictions on the format of the voltage curve, as long as the correspondence between the measurement time and the battery voltage is shown.
[0052] Specifically, Figure 2 The voltage curve was generated during the process of charging the battery from 3.4V to 4.3V. Then, the battery voltage was measured from time point t0 to time point t19 according to a preset measurement period (Δt). That is, the battery voltage was measured a total of 20 times during the battery charging process.
[0053] For example, curve acquisition unit 110 can receive voltage curves directly from an external source connected via wired and / or wireless means.
[0054] As another example, the curve acquisition unit 110 can receive battery information regarding the battery voltage and the voltage measurement time point. Furthermore, the curve acquisition unit 110 can generate a voltage curve based on the received battery information. In other words, the curve acquisition unit 110 can acquire a voltage curve by directly generating a voltage curve based on the battery information.
[0055] The curve acquisition unit 110 can be connected to communicate with the control unit 120. For example, the curve acquisition unit 110 can be connected to the control unit 120 via wired and / or wireless means. The curve acquisition unit can send the acquired voltage curve to the control unit 120.
[0056] The control unit 120 can be configured to determine a first voltage range and a second voltage range from multiple voltage curves acquired by the curve acquisition unit 110 in multiple cycles.
[0057] Specifically, the control unit 120 can receive voltage curves corresponding to each of the multiple cycles from the curve acquisition unit 110. For example, if the curve acquisition unit 110 acquires voltage curves for each of the first to nth cycles, the control unit 120 can receive a total of n voltage curves from the curve acquisition unit 110. The control unit 120 can determine a first voltage range and a second voltage range for the n voltage curves. Preferably, the first voltage range and the second voltage range are common voltage ranges for the n voltage curves.
[0058] First, the control unit 120 can determine a reference voltage range for multiple voltage curves. In one embodiment, the reference voltage range can be set based on the voltage ranges of the multiple voltage curves. For example, the reference voltage range can be set to a common voltage range of the multiple voltage curves. In another embodiment, the reference voltage range can be preset based on experiments or theories for diagnosing the state of the battery. For example, the reference voltage range can be preset to 3.8V to 4.2V.
[0059] In addition, the control unit 120 can be configured to divide the reference voltage range into a first voltage range and a second voltage range.
[0060] Specifically, the control unit 120 can be configured to divide a reference voltage range into a low-voltage range and a high-voltage range. The reference voltage range can be divided into a low-voltage range and a high-voltage range based on the voltage contained within that range. Furthermore, the control unit 120 can be configured to designate the low-voltage range as a first voltage range and the high-voltage range as a second voltage range.
[0061] For example, suppose the reference voltage range is a voltage range greater than or equal to Va and less than or equal to Vc, and Vb is included within the reference voltage range. That is, Va is less than Vb, and Vb is less than Vc. The reference voltage range can be divided into a low voltage range (greater than or equal to Va and less than or equal to Vb) and a high voltage range (greater than or equal to Vb and less than or equal to Vc) based on Vb. Furthermore, the low voltage range can be designated as the first voltage range, and the high voltage range can be designated as the second voltage range.
[0062] exist Figure 2 In this embodiment, it is assumed that the reference voltage range RV is set to a voltage range of 3.8V or higher and 4.2V or lower. The control unit 120 can divide the reference voltage range RV into a first voltage range RV1 and a second voltage range RV2 based on 4.0V. Here, the first voltage range RV1 is a voltage range of 3.8V or higher and 4.0V or lower, and the second voltage range RV2 is a voltage range of 4.0V or higher and 4.2V or lower.
[0063] The control unit 120 can be configured to determine, in each of a plurality of voltage curves, a first number of voltages contained in a first voltage range and a second number of voltages contained in a second voltage range.
[0064] Specifically, the control unit 120 can determine the first voltage quantity by counting the number of times the voltage is measured in the first voltage range. Furthermore, the control unit 120 can determine the second voltage quantity by counting the number of times the voltage is measured in the second voltage range. For example, if a voltage is measured at the upper limit of the first voltage range (the lower limit of the second voltage range), that voltage can be included in both the first voltage quantity and the second voltage quantity.
[0065] exist Figure 2 In this embodiment, since the battery voltage is measured 6 times in the first voltage range RV1, the control unit 120 can determine the first voltage quantity as 6. Furthermore, since the battery voltage is measured 4 times in the second voltage range, the control unit 120 can determine the second voltage quantity as 4. Here, since the voltage measured at 4.0V can be included in both the first voltage range RV1 and the second voltage range RV2, the first voltage quantity can be determined as 6, and the second voltage quantity can be determined as 4.
[0066] The control unit 120 can be configured to diagnose the state of the battery based on a first ratio of a plurality of first voltage quantities and a second ratio of a plurality of second voltage quantities.
[0067] Specifically, the control unit 120 can be configured to calculate a first ratio of each of a plurality of first voltage quantities based on a first reference quantity. Here, the control unit 120 can be configured to set the first voltage quantity of the initial cycle in a plurality of cycles as the first reference quantity. That is, the control unit 120 can calculate a ratio of the first voltage quantities of each cycle based on the first voltage quantity of the initial cycle. For example, assuming the first voltage quantity of the initial cycle is n, and the first voltage quantity of the k-th cycle is m, the control unit 120 can calculate "m ÷ n" or "m ÷ n × 100" to calculate the first ratio of the first voltage quantity of the k-th cycle.
[0068] Similarly, control unit 120 can be configured to calculate a second ratio of each of a plurality of second voltage quantities based on a second reference quantity. Control unit 120 can be configured to set the second voltage quantity of the initial cycle to the second reference quantity.
[0069] Figures 3 to 6 It is a diagram schematically showing the first and second ratios for each cycle of the first through fourth cells.
[0070] Figure 3 This diagram schematically illustrates a first curve P1 and a second curve P2 for the first battery. Here, the first curve P1 represents a first ratio for the first battery in each cycle. And the second curve P2 represents a second ratio for the first battery in each cycle. Comparing the first curve P1 and the second curve P2, the first ratio is higher than the second ratio in all cycles. Based on the fact that the first ratio is higher than the second ratio in multiple cycles, the control unit 120 can diagnose the state of the first battery as normal.
[0071] Figure 4 The diagram schematically illustrates the third curve P3 and the fourth curve P4 of the second battery. Here, the third curve P3 represents the first ratio of the second battery for each cycle. And the fourth curve P4 represents the second ratio of the second battery for each cycle. Comparing the third curve P3 and the fourth curve P4, in early cycles (e.g., before cycle k), the first ratio tends to be lower than the second ratio, but in subsequent cycles (e.g., after cycle k), the first ratio tends to be higher than the second ratio. Based on the fact that the first ratio is higher than the second ratio in the overall cycle (especially in cycles after the early cycles), the control unit 120 can diagnose the state of the second battery as normal.
[0072] Figure 5The diagram schematically illustrates the fifth curve P5 and the sixth curve P6 of the third battery. Here, the fifth curve P5 represents the first ratio of the third battery for each cycle. And the sixth curve P6 represents the second ratio of the third battery for each cycle. Comparing the fifth curve P5 and the sixth curve P6, the first ratio is lower than the second ratio in all cycles. Based on the fact that the first ratio is lower than the second ratio in multiple cycles, the control unit 120 can diagnose the state of the third battery as a warning state.
[0073] Figure 6 The diagram schematically illustrates the seventh and eighth curves of the fourth battery. Here, the seventh curve P7 represents the first ratio of the fourth battery for each cycle. The eighth curve represents the second ratio of the fourth battery for each cycle. Comparing the seventh and eighth curves, the first ratio is lower than the second ratio in all cycles. In particular, both the first and second ratios tend to decrease rapidly around 400 cycles. Based on the fact that the first ratio is lower than the second ratio in multiple cycles and that both the first and second ratios decrease rapidly in each cycle, the control unit 120 can diagnose the state of the fourth battery as an abnormal state.
[0074] The battery diagnostic apparatus 100 according to embodiments of this disclosure can diagnose the state of a battery by considering the variation patterns of the number of voltages measured within a predetermined voltage range, taking into account changes in battery state or performance. Furthermore, according to the battery diagnostic apparatus 100, since variation pattern analysis is relatively easy, battery diagnostics can be performed quickly, and system resources required for battery diagnostics can be saved. Additionally, since a method of counting the number of measured voltages is used, it has the advantage of being robust to noise compared to methods that diagnose battery state using measured voltage values.
[0075] Meanwhile, the curve acquisition unit 110 and / or control unit 120 included in the battery diagnostic device 100 may optionally include processors, application-specific integrated circuits (ASICs), other chipsets, logic circuits, registers, communication modems, data processing devices, etc., known in the art, to execute the various control logics performed in this disclosure. Furthermore, when the control logic is implemented as software, the curve acquisition unit 110 and / or control unit 120 can be implemented as a collection of program modules. In this case, the program modules can be stored in memory and executed by the curve acquisition unit 110 and / or control unit 120. The memory can be located internally or externally to the curve acquisition unit 110 and / or control unit 120, and can be connected to the curve acquisition unit 110 and / or control unit 120 by various well-known means.
[0076] In addition, the battery diagnostic device 100 may also include a storage unit 130. The storage unit 130 may store data necessary for the operation and function of each component of the battery diagnostic device 100, data generated during the execution of operations or functions, etc. The storage unit 130 is not particularly limited in its type, as long as it is a known information storage device capable of recording, erasing, updating, and retrieving data. As examples, the information storage device may include RAM, flash memory, ROM, EEPROM, registers, etc. Furthermore, the storage unit 130 may store program code defining processes that can be executed by each component of the battery diagnostic device 100.
[0077] For example, storage unit 130 can store voltage curves acquired by curve acquisition unit 110. Control unit 120 can also access storage unit 130 to acquire voltage curves.
[0078] An embodiment in which the control unit 120 diagnoses the state of the battery is described in more detail below.
[0079] The control unit 120 can be configured to compare a first ratio and a second ratio. Specifically, the control unit 120 can compare the first ratio and the second ratio for each cycle. Furthermore, the control unit 120 can be configured to diagnose the battery state as normal, warning, or abnormal based on the comparison result.
[0080] In one embodiment, the control unit 120 may be configured to diagnose the battery state as normal if the first ratio is greater than the second ratio.
[0081] Specifically, the first voltage range is more affected by the negative electrode than the second voltage range, and the second voltage range is more affected by the positive electrode than the first voltage range. Therefore, the first ratio reflects the state of the negative electrode, and the second ratio reflects the state of the positive electrode.
[0082] More specifically, as the battery deteriorates, the capacity of the positive and negative electrodes decreases, and as the capacity of the positive and negative electrodes decreases, the number of voltage measurements taken according to a predetermined measurement cycle within a specific voltage range also decreases.
[0083] For example, in the initial state, assume that the voltage is measured 10 times according to a predetermined measurement cycle within a constant voltage range. Subsequently, if the battery deteriorates and the capacity corresponding to the constant voltage range decreases, the number of voltage measurements according to the predetermined measurement cycle may be less than 10. This is because charging proceeds faster as capacity decreases, thus reducing the number of voltage measurements according to the predetermined measurement cycle. Note that the charging rate C is the same from the initial state.
[0084] That is, the voltage range can vary depending on the degradation state of the positive and negative electrodes. Therefore, the ratio of electrodes with greater capacity reduction (more degraded electrodes) may be lower. For example, if the first ratio is greater than the second ratio, it means that less degradation has occurred on the negative electrode than on the positive electrode. As another example, if the first ratio is less than the second ratio, it means that more degradation has occurred on the negative electrode than on the positive electrode.
[0085] Typically, since battery degradation occurs more at the positive electrode than the negative electrode, the first ratio may be greater than the second ratio in a normally degraded battery. Therefore, if the first ratio is greater than the second ratio, the control unit 120 determines that the positive electrode has degraded more than the negative electrode and can diagnose the battery state as normal.
[0086] exist Figure 3 In this embodiment, when comparing the first curve P1 and the second curve P2, the first ratio is greater than the second ratio throughout the entire cycle. Therefore, the control unit 120 can diagnose the battery state as normal.
[0087] In another embodiment, if the first ratio is less than or equal to the second ratio, the control unit 120 can diagnose the battery state as a warning state or an abnormal state.
[0088] Preferably, if the first ratio is lower than or equal to the second ratio in a preset number of consecutive cycles, the control unit 120 can diagnose the battery state as a warning state or an abnormal state. For example, assuming the preset number of cycles is 10, if the first ratio is lower than or equal to the second ratio in 10 or more consecutive cycles, the control unit 120 can diagnose the battery state as a warning state or an abnormal state. That is, the control unit 120 can check whether the first ratio continuously shows a value lower than or equal to the second ratio in order to reduce the possibility of false diagnosis due to measurement noise.
[0089] As mentioned earlier, battery degradation typically occurs more at the positive electrode than the negative electrode, and in normally degraded batteries, the first ratio is greater than the second ratio. Therefore, batteries with a first ratio lower than the second ratio cannot be considered to be in a normal state, and the control unit 120 can additionally diagnose such batteries.
[0090] Specifically, if the first ratio is less than or equal to the second ratio, the control unit 120 can be configured to compare the first rate of change of the first ratio and the second rate of change of the second ratio with a preset reference rate of change.
[0091] Here, the first rate of change refers to the rate of change of the first ratio, and the second rate of change refers to the rate of change of the second ratio. Specifically, the control unit 120 can set the first rate of change by calculating the rate of change of the first ratio for each cycle, and can set the second rate of change by calculating the rate of change of the second ratio for each cycle.
[0092] The control unit 120 can generate a regression model of a curve representing a first rate for each cycle, and set the rate of change of the generated regression model as the first rate of change. In other words, the first rate of change can be considered an indicator of the rate of negative degradation. For example, the control unit 120 can set the value with the largest absolute value among the instantaneous rates of change of each cycle of the regression model as the first rate of change.
[0093] Similarly, the control unit 120 can generate a regression model of a curve representing a second ratio for each cycle, and set the rate of change of the generated regression model as the second rate of change. In other words, the second rate of change can be considered an indicator of the rate of positive degradation. For example, the control unit 120 can set the value with the largest absolute value among the instantaneous rates of change of each cycle of the regression model as the second rate of change.
[0094] Furthermore, the reference change rate is a preset value that distinguishes the battery state into warning states and abnormal states. Preferably, the reference change rate can be preset through experiments or theory. Here, a warning state is a state that requires battery inspection, and an abnormal state is an EOL (end of life) state where battery use is not recommended. In other words, the reference change rate is an indicator representing a reference rate compared to the degradation rate of the positive and negative electrodes.
[0095] The control unit 120 can be configured to compare a first rate of change with a reference rate of change, compare a second rate of change with a reference rate of change, and diagnose the state of the battery as a warning state or an abnormal state based on the comparison results.
[0096] For example, if the first rate of change and the second rate of change are less than or equal to the reference rate of change, the control unit 120 can be configured to diagnose the battery state as a warning state. That is, even though the negative electrode of the battery is in a state of more degradation than the positive electrode, because the rate of degradation of both the positive and negative electrodes is less than or equal to the reference rate, the control unit 120 can diagnose the battery state as a warning state that requires inspection.
[0097] exist Figure 5In this embodiment, the control unit 120 can generate a fifth regression model R5 for the fifth curve P5 and set the rate of change of the fifth regression model R5 as a first rate of change. The control unit 120 can generate a sixth regression model R6 for the sixth curve P6 and set the rate of change of the sixth regression model R6 as a second rate of change. Since the first rate of change and the second rate of change are lower than the reference rate of change, the control unit 120 can diagnose the state of the third battery as a warning state.
[0098] As another example, if the first rate of change and the second rate of change exceed a reference rate of change, the control unit 120 can be configured to diagnose the battery state as an abnormal state. That is, since the negative electrode of the battery deteriorates more than the positive electrode and the rate of deterioration of both the positive and negative electrodes exceeds a reference rate, the control unit 120 can diagnose the battery state as an abnormal state. Since the deterioration of a battery in the end-of-life (EOL) state gradually accelerates, if the first rate of change and the second rate of change exceed a reference rate of change, the control unit 120 can diagnose the battery state as an abnormal state.
[0099] exist Figure 6 In this embodiment, the control unit 120 can generate a seventh regression model R7 for the seventh curve P7 and set the rate of change of the seventh regression model R7 as a first rate of change. The control unit 120 can generate an eighth regression model R8 for the eighth curve and set the rate of change of the eighth regression model R8 as a second rate of change. Since the rates of change of the seventh regression model R7 and the eighth regression model R8 become greater than the reference rate of change at approximately 400 cycles, the control unit 120 can diagnose the battery state as an abnormal state.
[0100] The battery diagnostic apparatus 100 according to embodiments of the present disclosure has the advantage of more accurately diagnosing the current state of the battery by diagnosing the battery's state in detail. Furthermore, the battery diagnostic apparatus 100 has the advantage of being able to diagnose the current state of the battery more accurately by considering not only the increase and decrease in the number of voltage measurements (e.g., a first ratio and a second ratio) but also the rate of increase and decrease in the number of voltage measurements (e.g., a first rate of change and a second rate of change).
[0101] The control unit 120 can be configured to diagnose the battery status based on a cycle that is greater than or equal to a preset reference cycle among multiple cycles.
[0102] Typically, when a battery in its beginning-of-life (BOL) state is charged and discharged, a stabilization reaction occurs, in which a solid electrolyte interphase (SEI) layer is formed, the volume of the negative electrode material changes, and the electrochemical properties are stabilized. Since the structure of the negative electrode material gradually stabilizes due to the stabilization reaction, the first ratio may be affected by the stabilization reaction. In other words, since it is desirable to exclude the amount of voltage generated during the negative electrode stabilization reaction from the diagnostic battery state, the control unit 120 can diagnose the battery state based on cycles greater than or equal to a reference cycle.
[0103] Here, the reference cycle can be preset to a cycle in which the negative electrode stabilization reaction of the battery no longer occurs. For example, typically, the negative electrode stabilization reaction can proceed for approximately 10 to 100 cycles. Assuming the reference cycle is preset to the 101st cycle, the control unit 120 can diagnose the state of the battery based on a first voltage number and a second voltage number greater than the 101st cycle.
[0104] For example, in Figure 4 In this embodiment, the reference cycle is preset to the k-th cycle. Since the negative electrode stabilization reaction of the battery is active in cycles prior to the reference cycle, many cycles occur where the first ratio is lower than or equal to the second ratio. Additionally, some cycles where the first ratio is lower than or equal to the second ratio also occur after the reference cycle. However, since the first ratio does not fall below the second ratio and is greater than the second ratio in consecutive cycles of a preset number or more, the control unit 120 can diagnose the state of the second battery as normal.
[0105] The battery diagnostic device 100 according to embodiments of the present disclosure has the advantage of being able to diagnose the state of the battery more accurately by taking into account the noise generated due to the negative electrode stabilization reaction.
[0106] The following describes in detail an embodiment in which the control unit 120 sets a reference voltage range.
[0107] The control unit 120 can be configured to set a reference voltage range in multiple voltage curves.
[0108] Specifically, the control unit 120 can be configured to set a preset voltage range or a common voltage range of multiple voltage curves as a reference voltage range.
[0109] For example, if there is a common voltage range among multiple voltage curves, the control unit 120 can be configured to set the common voltage range as a reference voltage range. Preferably, the control unit 120 can set the common voltage range in a cycle greater than or equal to the reference cycle as the reference voltage range.
[0110] As another example, if a common voltage range does not exist, the control unit 120 can be configured to set a preset voltage range as a reference voltage range. In this case, the control unit 120 can be configured to exclude voltage curves from the diagnostic battery state that do not include at least a portion of the reference voltage range.
[0111] Specifically, if some voltage curves do not include a reference voltage range, the first voltage quantity and the second voltage quantity calculated from these voltage curves cannot be used to calculate the first ratio and the second ratio. Therefore, the control unit 120 can diagnose the battery state based on voltage curves that include a reference voltage range among multiple voltage curves.
[0112] The battery diagnostic device 100 according to this disclosure can be applied to a battery management system (BMS). That is, the BMS according to this disclosure may include the battery diagnostic device 100 described above. In this configuration, at least some of the components of the battery diagnostic device 100 can be implemented by supplementing or adding the functionality of components included in a conventional BMS. For example, the curve acquisition unit 110, control unit 120, and storage unit 130 of the battery diagnostic device 100 can be implemented as components of the BMS.
[0113] Furthermore, the battery diagnostic device 100 according to this disclosure can be equipped in a battery pack. That is, the battery pack according to this disclosure may include the aforementioned battery diagnostic device 100 and at least one battery cell. In addition, the battery pack may also include electrical components (relays, fuses, etc.) and a casing, etc.
[0114] Figure 7 This is a schematic diagram illustrating a battery pack 10 according to another embodiment of the present disclosure.
[0115] The positive terminal of battery 11 can be connected to the positive terminal P+ of battery pack 10, and the negative terminal of battery 11 can be connected to the negative terminal P- of battery pack 10.
[0116] The measurement unit 12 can be connected to the first sensing line SL1, the second sensing line SL2 and the third sensing line SL3.
[0117] Specifically, the measurement unit 12 can be connected to the positive terminal of the battery 11 via a first sensing line SL1 and to the negative terminal of the battery 11 via a second sensing line SL2. The measurement unit 12 can measure the voltage of the battery 11 based on the voltage measured from each of the first sensing line SL1 and the second sensing line SL2. At this time, the measurement unit 12 can measure the voltage of the battery 11 according to a preset measurement cycle.
[0118] Furthermore, the measuring unit 12 can be electrically connected to the current measuring unit A via 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 and calculate the charging amount via the third sensing line SL3. Additionally, the measuring unit 12 can measure the discharging current of the battery 11 and calculate the discharging amount via the third sensing line SL3.
[0119] For example, curve acquisition unit 110 can directly receive the battery voltage curve from measurement unit 12.
[0120] As another example, the curve acquisition unit 110 can receive voltage information about the battery from the measurement unit 12 and generate a voltage curve based on the received voltage information.
[0121] An external device can be connected to the positive terminal P+ and the negative terminal P- of the battery pack 10. For example, the external device can 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 can be electrically connected.
[0122] The battery pack according to embodiments of this disclosure can be included in a vehicle (not shown), such as an electric vehicle (EV) or a hybrid vehicle (HV). Furthermore, the battery pack can power a motor via an inverter located within the vehicle to drive the vehicle. Here, the battery pack may include a battery diagnostic device 100. That is, the battery diagnostic device 100 can be included in the vehicle. In this case, the battery diagnostic device 100 can be an on-board device included in the vehicle.
[0123] Figure 8 This is a schematic diagram illustrating a battery diagnostic method according to yet another embodiment of the present disclosure.
[0124] Reference Figure 8 The battery diagnostic method may include a curve acquisition step (S100), a voltage range determination step (S200), a voltage quantity determination step (S300), and a diagnostic step (S400).
[0125] Preferably, each step of the battery diagnostic method can be performed by the battery diagnostic device 100. In the following text, for ease of explanation, content overlapping with the foregoing will be briefly described or omitted.
[0126] The curve acquisition step (S100) is a step of acquiring the voltage curve of the battery voltage measured according to a preset measurement cycle, and can be executed by the curve acquisition unit 110.
[0127] For example, curve acquisition unit 110 can receive voltage curves directly from an external source connected via wired and / or wireless means.
[0128] As another example, the curve acquisition unit 110 can receive battery information regarding battery voltage and voltage measurement time points. Then, the curve acquisition unit 110 can generate a voltage curve based on the received battery information. That is, the curve acquisition unit 110 can acquire a voltage curve by directly generating a voltage curve based on the battery information.
[0129] The voltage range determination step (S200) is a step of determining a first voltage range and a second voltage range from multiple voltage curves obtained in the curve acquisition step (S100), and can be executed by the control unit 120.
[0130] First, the control unit 120 can determine reference voltage ranges for multiple voltage curves. Additionally, the control unit 120 can be configured to divide the reference voltage ranges into a first voltage range and a second voltage range.
[0131] Specifically, the control unit 120 can be configured to divide a reference voltage range into a low-voltage range and a high-voltage range. The reference voltage range can be divided into low-voltage and high-voltage ranges based on the voltage contained within that range. Furthermore, the control unit 120 can be configured to designate the low-voltage range as a first voltage range and the high-voltage range as a second voltage range.
[0132] The voltage quantity determination step (S300) is a step of determining a first voltage quantity of voltages included in a first voltage range and a second voltage quantity of voltages included in a second voltage range in each of a plurality of voltage curves, and can be executed by the control unit 120.
[0133] Specifically, the control unit 120 can determine the first voltage quantity by counting the number of times the voltage is measured in the first voltage range. Furthermore, the control unit 120 can determine the second voltage quantity by counting the number of times the voltage is measured in the second voltage range. For example, if a voltage is measured at the upper limit of the first voltage range (the lower limit of the second voltage range), that voltage can be included in both the first voltage quantity and the second voltage quantity.
[0134] The diagnostic step (S400) is a step of diagnosing the state of the battery based on a first ratio of a plurality of first voltage quantities and a second ratio of a plurality of second voltage quantities, and can be executed by the control unit 120.
[0135] Specifically, the control unit 120 can calculate a first ratio of each of a plurality of first voltage quantities based on a first reference quantity, and can calculate a second ratio of each of a plurality of second voltage quantities based on a second reference quantity. Furthermore, the control unit 120 can diagnose the battery state as normal, warning, or abnormal based on the result of comparing the first and second ratios.
[0136] For example, the control unit 120 can be configured to diagnose the battery state as normal if the first ratio is greater than the second ratio.
[0137] As another example, if the first rate of change is less than or equal to the second rate of change, the control unit 120 can diagnose the battery state as a warning state or an abnormal state. Specifically, if the first rate of change and the second rate of change are less than or equal to a reference rate of change, the control unit 120 can be configured to diagnose the battery state as a warning state. Conversely, if the first rate of change and the second rate of change exceed the reference rate of change, the control unit 120 can be configured to diagnose the battery state as an abnormal state.
[0138] The embodiments of this disclosure described above can be implemented not only by apparatus and methods, but also by a program that implements functions corresponding to the configuration of the embodiments of this disclosure, or a recording medium on which the program is recorded. Those skilled in the art can readily implement the program or recording medium based on the above description of the embodiments.
[0139] Another embodiment of this disclosure may provide a computer-readable storage medium having programs recorded thereon for executing the various embodiments described above on a computer.
[0140] A program can be implemented as a hardware component, a software component, and / or a combination of hardware and software components. The program can be executed by any system capable of executing computer-readable instructions.
[0141] Software may include computer programs, code, instructions, or combinations thereof, which may configure processing equipment to perform desired operations or may independently or jointly command processing equipment.
[0142] Software can be implemented as a computer program that includes 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 optically readable media (e.g., CD-ROM, DVD (Digital Versatile Optical Disc)). Computer-readable storage media can be distributed across computer systems on a network, allowing computer-readable code to be stored and executed in a distributed manner. The storage medium can be read by a computer, stored in memory, and executed by a processor.
[0143] Computer-readable storage media may be provided in the form of non-transitory storage media. Here, the term "non-transitory storage media" simply means that it is a tangible device and does not contain signals (e.g., electromagnetic waves), and the term does not distinguish between cases where data is stored semi-permanently on the storage medium and cases where data is temporarily stored. For example, a "non-transitory storage medium" may include a buffer in which data is temporarily stored.
[0144] Furthermore, programs can be provided as part of a computer program product. Computer program products can be traded as commodities between sellers and buyers.
[0145] Computer program products may include software programs and computer-readable storage media storing the software programs. For example, a computer program product may include a product that is electronically distributed in the form of a software program (e.g., a downloadable application) 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 the storage medium of a server of an electronic device manufacturer, a server of an electronic marketplace, or a relay server temporarily storing the software program.
[0146] This disclosure has been described in detail. However, it should be understood that while the detailed description and specific examples indicate preferred embodiments of this disclosure, they are given by way of illustration only, as various changes and modifications within the scope of this disclosure will be apparent to those skilled in the art based on the detailed description.
[0147] Furthermore, those skilled in the art can make many substitutions, modifications and changes to the present disclosure described above without departing from the technical aspects of the present disclosure, and the present disclosure is not limited to the above embodiments and drawings, and each embodiment can be selectively combined in part or in whole to allow various modifications.
[0148] [Explanation of reference numerals in the attached figures]
[0149] 10: Battery Pack
[0150] 11: Battery
[0151] 12: Measurement Unit
[0152] 100: Battery diagnostic device
[0153] 110: Curve Acquisition Unit
[0154] 120: Control Unit
[0155] 130: Storage unit
Claims
1. A battery diagnostic device, comprising: A curve acquisition unit is configured to acquire a voltage curve of a battery voltage measured according to a preset measurement cycle. as well as A control unit is configured to determine a first voltage range and a second voltage range from a plurality of voltage curves acquired by the curve acquisition unit in a plurality of cycles, determine a first number of voltages contained in the first voltage range and a second number of voltages contained in the second voltage range in each of the plurality of voltage curves, and diagnose the state of the battery based on a first ratio of the plurality of first voltages and a second ratio of the plurality of second voltages.
2. The battery diagnostic device according to claim 1, in, The control unit is configured to compare the first ratio with the second ratio and diagnose the state of the battery as normal, warning, or abnormal based on the comparison result.
3. The battery diagnostic device according to claim 2, in, The control unit is configured to diagnose the state of the battery as the normal state when the first ratio is greater than the second ratio.
4. The battery diagnostic device according to claim 2, in, When the first ratio is less than or equal to the second ratio, the control unit is configured to compare the first rate of change of the first ratio and the second rate of change of the second ratio with a preset reference rate of change, and diagnose the state of the battery as the warning state or the abnormal state based on the comparison result.
5. The battery diagnostic device according to claim 4, in, The control unit is configured to: When the first rate of change and the second rate of change are less than or equal to the reference rate of change, the state of the battery is diagnosed as the warning state, and When the first rate of change and the second rate of change exceed the reference rate of change, the state of the battery is diagnosed as the abnormal state.
6. The battery diagnostic device according to claim 1, in, The control unit is configured to set a reference voltage range in the plurality of voltage curves and to divide the reference voltage range into a first voltage range and a second voltage range.
7. The battery diagnostic device according to claim 6, in, The control unit is configured to divide the reference voltage range into a low voltage range and a high voltage range, setting the low voltage range as the first voltage range and the high voltage range as the second voltage range.
8. The battery diagnostic device according to claim 6, in, The control unit is configured to exclude voltage curves from the plurality of voltage curves that do not contain at least a portion of the reference voltage range from the diagnosis of the state of the battery.
9. The battery diagnostic device according to claim 6, in, The control unit is configured to set a preset voltage range or a common voltage range of the plurality of voltage curves as the reference voltage range.
10. The battery diagnostic device according to claim 9, in, The control unit is configured to: When a common voltage range exists among the plurality of voltage curves, the common voltage range is set as the reference voltage range, and When the common voltage range does not exist, the preset voltage range is set as the reference voltage range.
11. The battery diagnostic device according to claim 1, in, The control unit is configured to calculate a first ratio of each of the plurality of first voltage quantities based on a first reference quantity, and to calculate a second ratio of each of the plurality of second voltage quantities based on a second reference quantity.
12. The battery diagnostic device according to claim 11, in, The control unit is configured to set a first voltage quantity of the initial cycle in the plurality of cycles to the first reference quantity, and to set a second voltage quantity of the initial cycle to the second reference quantity.
13. The battery diagnostic device according to claim 1, in, The control unit is configured to diagnose the state of the battery based on a cycle that is greater than or equal to a preset reference cycle among the plurality of cycles.
14. A battery pack comprising a battery diagnostic device according to any one of claims 1 to 13.
15. A battery diagnostic method, comprising: The curve acquisition step involves acquiring the voltage curve of the battery voltage measured according to a preset measurement cycle. The voltage range determination step involves determining a first voltage range and a second voltage range from multiple voltage curves obtained in the curve acquisition step. The voltage quantity determination step involves determining, in each of the plurality of voltage curves, a first voltage quantity containing voltages in the first voltage range and a second voltage quantity containing voltages in the second voltage range; as well as The diagnostic steps diagnose the state of the battery based on a first ratio of a plurality of first voltage quantities and a second ratio of a plurality of second voltage quantities.
Citation Information
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A vehicle signaling system with multiple force generators for generating user experience feedback.
KR1020240168345A