Apparatus for diagnosing battery state and method thereof

Abstract

The present invention relates to a battery condition diagnostic device comprising: a voltage sampling unit for measuring the voltage of an upper battery and a lower battery connected in series; a time control unit for measuring the elapsed time from the start of current supply; a communication unit for transmitting and receiving data with an external device; and a microcontroller unit for diagnosing the condition of the battery using voltage data measured from the voltage sampling unit and time data obtained from the time control unit. The microcontroller unit is characterized by supplying current to the lower battery when the voltage of the lower battery is lower than a reference voltage, calculating an effective capacity or voltage rise rate using a voltage change amount and a time change amount, and determining whether the battery is degraded by comparing the calculated value with a threshold value.

Description

Technology Field

[0001] The present invention relates to battery management technology, and more specifically, to a battery condition diagnosis device and method that enable the diagnosis of the degradation state of a battery using a battery equalizer. Background Technology

[0003] Generally, in the power systems of commercial vehicles, two 12V batteries are connected in series to form a 24V power supply. In this series connection structure, voltage imbalance between the two batteries may occur during use, and a battery equalizer (hereinafter referred to as 'BEQ') is used to resolve this.

[0004] Conventional BEQs operate by measuring the total voltage and setting a reference voltage, and then supplying current to the lower battery if the voltage of the lower battery is lower than the reference voltage. Such BEQs consist of a DC-DC converter (Direct Current to Direct Current Converter, a device that converts direct current into direct current of a different voltage) for charging and discharging and a simple voltage detection circuit, and perform only balancing operations based on simple voltage comparison.

[0005] However, in most commercial vehicles, a Battery Management System (hereinafter referred to as 'BMS') is not applied due to driving conditions, vibration, and installation space issues, and conventional BEQ also lacks the function to evaluate or diagnose the condition of the battery other than simple balancing functions.

[0006] Therefore, conventional technology has the problem of being unable to detect changes in the battery's state, such as a decrease in State of Health (hereinafter referred to as 'SOH,' an indicator of the battery's health status) or an increase in internal resistance. Furthermore, even if degraded batteries are mixed in, they cannot be identified early, which may lead to a decrease in system efficiency and safety as charging attempts continue.

[0007] Furthermore, since the battery condition cannot be accurately assessed even during maintenance, there is a problem of reduced maintainability as one is forced to rely on a complete replacement or arbitrary replacement of the battery.

[0008] Accordingly, there is a need for technology capable of diagnosing battery condition and determining degradation even in commercial vehicle environments where BMS is not applied.

[0009] The background technology of the present invention is disclosed in Korean Registered Patent No. 10-2539821 (registered on May 31, 2023). The problem to be solved

[0011] According to one aspect, the present invention aims to provide a battery condition diagnosis device and method that enable the diagnosis of the degradation state of a battery using only a battery equalizer without a BMS.

[0012] According to another aspect, the present invention aims to provide a battery condition diagnosis device and method that can diagnose the battery condition using only voltage change amount and time information by utilizing the current supply operation of an existing battery equalizer without additional sensors or circuits.

[0013] According to another aspect, the present invention aims to provide a battery condition diagnostic device and method that can improve maintenance efficiency by detecting battery degradation early and providing criteria for battery replacement or maintenance.

[0014] According to another aspect, the present invention aims to provide a battery condition diagnostic device and method that enable effective management of the battery condition even in commercial vehicle environments where a BMS is not applied. means of solving the problem

[0016] A battery condition diagnostic device according to one aspect of the present invention comprises: a voltage sampling unit for measuring the voltage of an upper battery and a lower battery connected in series; a time control unit for measuring the elapsed time from the start of current supply; a communication unit for transmitting and receiving data with an external device; and a microcontroller unit for diagnosing the condition of the battery using voltage data measured from the voltage sampling unit and time data obtained from the time control unit. The microcontroller unit is characterized by supplying current to the lower battery when the voltage of the lower battery is lower than a reference voltage, calculating an effective capacity or voltage rise rate using a voltage change amount and a time change amount, and determining whether the battery is degraded by comparing the calculated value with a threshold value.

[0017] In the present invention, the voltage sampling unit is characterized by including an ADC that converts an analog signal into a digital signal.

[0018] In the present invention, the microcontroller unit is characterized by calculating the total voltage by adding the voltage of the upper battery and the voltage of the lower battery, and calculating the reference voltage by dividing the total voltage by 2.

[0019] In the present invention, the microcontroller unit is characterized by further including a memory for storing diagnostic results.

[0020] In the present invention, the communication unit is characterized by transmitting a diagnostic result through at least one communication interface among CAN, UART, or GPIO.

[0022] A battery condition diagnosis method according to another aspect of the present invention comprises: a step in which a microcontroller unit measures the voltages of an upper battery and a lower battery through a voltage sampling unit; a step in which the microcontroller unit calculates a total voltage and a reference voltage using the measured voltage data; a step in which the microcontroller unit determines whether the voltage of the lower battery is lower than the reference voltage; a step in which, if the result of the determination is that the voltage of the lower battery is lower than the reference voltage, the microcontroller unit starts supplying current to the lower battery; a step in which the microcontroller unit measures an initial voltage and initializes a timer; a step in which the microcontroller unit measures the voltage after a preset time has elapsed; a step in which the microcontroller unit calculates the voltage change amount; a step in which the microcontroller unit calculates the effective capacity or the voltage rise rate; a step in which the microcontroller unit determines whether degradation has occurred by comparing the calculated value with a threshold value; and a step in which, if degradation is determined in the step of determining whether degradation has occurred, the microcontroller unit generates a warning flag and stores and transmits the diagnosis result.

[0023] In the present invention, the step of calculating the effective capacity or voltage rise rate is characterized in that the microcontroller unit calculates the effective capacity by dividing the value obtained by multiplying the supply current value by the time change amount by the voltage change amount.

[0024] In the present invention, the step of determining whether degradation has occurred is characterized in that the microcontroller unit determines that the battery is degraded when the effective capacity is less than 50% of the rated capacity or when the voltage rise rate is less than a reference rise rate.

[0026] A battery condition diagnosis method according to another aspect of the present invention comprises: a step in which a microcontroller unit measures the voltage of an upper battery and a lower battery; a step in which the microcontroller unit determines whether the voltage of the lower battery is lower than a reference voltage; a step in which, if the result of the determination is that the voltage of the lower battery is lower than the reference voltage, the microcontroller unit starts supplying current to the lower battery and sets a plurality of time intervals; a step in which the microcontroller unit measures the voltage for each time interval and calculates a voltage rise rate value; a step in which the microcontroller unit performs statistical processing on the measured plurality of voltage rise rate values; a step in which the microcontroller unit compares an average value with a threshold value and evaluates reliability using a coefficient of variation; a step in which, if the reliability is greater than or equal to a reference and the average value is less than the threshold value, the microcontroller unit determines that there is deterioration; a step in which the microcontroller unit increases the accumulated count of the diagnosis result; and a step in which, if the accumulated count exceeds a preset number of times, the microcontroller unit generates a confirmed warning.

[0027] In the present invention, the step of performing the statistical processing is characterized in that the microcontroller unit calculates the average value, standard deviation, and coefficient of variation for the plurality of voltage rise rate values.

[0029] A battery condition diagnosis method according to another aspect of the present invention comprises: a step in which a microcontroller unit detects the installation of a new battery; a step in which the microcontroller unit enters an initial learning mode; a step in which the microcontroller unit collects voltage change data during a plurality of charging cycles; a step in which the microcontroller unit generates a reference profile including an average voltage rise rate value and a normal range from the collected data; a step in which the microcontroller unit stores the reference profile in memory; a step in which the microcontroller unit switches to a normal operation mode; a step in which the microcontroller unit periodically performs a diagnosis to measure a current voltage rise rate value; a step in which the microcontroller unit calculates a deviation from the reference profile; and a step in which, if the deviation exceeds an allowable range, the microcontroller unit generates a step-by-step warning.

[0030] The present invention is characterized by further including the step of the microcontroller unit gradually updating the reference profile based on long-term usage data. Effects of the invention

[0032] According to one aspect, the present invention enables the diagnosis of the degradation state of a battery using only a battery equalizer without a BMS, thereby providing a battery management solution suitable for commercial vehicle environments where the application of a BMS is difficult.

[0033] According to another aspect, the present invention enables the addition of a battery status diagnostic function without the need for a separate circuit or expensive sensor, thereby enabling the implementation of a battery management function at a low cost.

[0034] According to another aspect, the present invention enables the detection of an increase in internal resistance and a decrease in capacity of a battery in advance, thereby preventing battery failure at an early stage.

[0035] According to another aspect, the present invention enables a battery replacement decision based on diagnostic data, thereby allowing for the reasonable setting of maintenance cycles and the improvement of maintenance efficiency.

[0036] According to another aspect, the present invention enables the prevention of reduced system efficiency and safety through the early detection of degraded batteries. Brief explanation of the drawing

[0038] FIG. 1 is an exemplary diagram showing the schematic configuration of a battery condition diagnostic device according to one embodiment of the present invention. FIG. 2 is a flowchart illustrating a battery condition diagnosis method according to an embodiment of the present invention. FIG. 3 is a flowchart illustrating a battery condition diagnosis method according to another embodiment of the present invention. FIG. 4 is a flowchart illustrating a battery condition diagnosis method according to another embodiment of the present invention. Specific details for implementing the invention

[0039] Hereinafter, an embodiment according to the present invention will be described with reference to the attached drawings. In this process, the thickness of lines or the size of components depicted in the drawings may be exaggerated for clarity and convenience of explanation. Furthermore, the terms described below are defined considering their functions in the present invention, and these may vary depending on the intention or convention of the user or operator. Therefore, the definitions of these terms should be based on the content throughout this specification.

[0040] Embodiments of the present invention are described below with reference to the attached drawings so that those skilled in the art can easily implement them. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein. Furthermore, in order to clearly explain the present invention in the drawings, parts unrelated to the explanation have been omitted, and similar parts throughout the specification are denoted by similar reference numerals.

[0041] Throughout the specification, when a part is described as "including" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0042] Terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0043] Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely some of the most preferred embodiments of the invention and do not represent all of the technical spirit of the invention; therefore, it should be understood that various equivalents and modifications capable of replacing them may exist at the time of filing this application. Furthermore, as used herein, "comprise" or "include" and / or "comprising" or "including" specify the presence of the mentioned features, numbers, steps, actions, parts, elements, and / or groups thereof, and do not exclude the presence or addition of one or more other features, numbers, actions, parts, elements, and / or groups. Additionally, when describing embodiments of the invention, "may" or "may be" may include "one or more embodiments of the invention."

[0044] Additionally, to aid in understanding the invention, the attached drawings are not drawn to actual scale, and the dimensions of some components may be exaggerated. Furthermore, the same reference numerals may be assigned to identical components in different embodiments.

[0045] The statement that two subjects of comparison are 'identical' means that they are 'substantially identical.' Therefore, substantial identity may include deviations considered low in the industry, for example, deviations within 5%. Additionally, the statement that a parameter is uniform in a given area may mean that it is uniform from an average perspective.

[0046] Although terms such as "first," "second," etc., are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless specifically stated otherwise, the first component may also be the second component.

[0047] Throughout the specification, unless specifically stated otherwise, each component may be singular or plural.

[0048] The fact that any configuration is placed on the “upper (or lower)” of a component or on the “upper (or lower)” of a component may mean not only that the any configuration is placed in contact with the upper (or lower) surface of said component, but also that another configuration may be interposed between said component and any configuration placed on (or below) said component.

[0049] Furthermore, where it is stated that one component is “connected,” “coupled,” or “joined” to another component, it should be understood that while said components may be directly connected or joined to one another, another component may be “interposed” between each component, or that each component may be “connected,” “coupled,” or “joined” through another component. Additionally, when it is stated that a part is electrically coupled to another part, this includes not only cases where they are directly connected but also cases where they are connected with an intermediate element in between.

[0050] Throughout the specification, “A and / or B” means A, B, or A and B unless specifically stated otherwise. That is, “and / or” includes any combination or any combination of the enumerated items. “C to D” means C or more and D or less, unless specifically stated otherwise.

[0052] FIG. 1 is an exemplary diagram showing the schematic configuration of a battery condition diagnostic device according to one embodiment of the present invention.

[0053] Referring to FIG. 1, the battery condition diagnostic device according to the present embodiment may include a vehicle system (10), a micro controller unit (Micro Controller Unit, hereinafter referred to as 'MCU') (110) functioning as a battery equalizer (hereinafter referred to as 'BEQ'), an upper battery (120), a lower battery (130), a 24V load (140), and a 12V load (150).

[0054] The vehicle system (10) is a system that supplies power to a commercial vehicle and generates 24V power through two 12V batteries connected in series to supply power to various electrical components of the vehicle. The vehicle system (10) can perform pressure transmission (pressure transmission means supplying current) to the BEQ.

[0055] BEQ includes an MCU (110) and is a device for resolving voltage imbalance between an upper battery (120) and a lower battery (130). BEQ may include a DC-DC converter (Direct Current to Direct Current Converter, a device that converts a DC voltage to a different level of DC voltage) and performs a charging operation to supply current to the lower battery (130) when the voltage of the lower battery (130) is lower than the reference voltage.

[0056] The MCU (110) is a processor that performs control and diagnostic functions of the BEQ and may include a communication unit (111), a voltage sampling unit (112), and a time control unit (113).

[0057] The communication unit (111) transmits and receives data with an external device through a communication interface such as CAN (Controller Area Network, a network protocol for communication between electronic control units in a vehicle) or UART (Universal Asynchronous Receiver / Transmitter, an asynchronous serial communication interface). The communication unit (111) can transmit the diagnostic results to the vehicle system (the vehicle's upper control unit or maintenance equipment) and can output a warning signal.

[0058] The voltage sampling unit (112) includes an ADC (Analog to Digital Converter, a device that converts an analog signal into a digital signal) and periodically measures the voltage (Vh) of the upper battery (120) and the voltage (Vl) of the lower battery (130). The voltage sampling unit (112) samples the battery voltage at regular time intervals, converts it into a digital value, and then transmits it to the operation logic inside the MCU (110).

[0059] The time control unit (113) performs a timer function that measures and records the elapsed time (△t) from the point when the current supply begins. The time control unit (113) initializes the timer at the time when battery charging begins, and then calculates the elapsed time in real time to provide time information necessary for voltage change rate analysis.

[0060] The MCU (110) performs a calculation to diagnose the state of the battery using voltage data measured from the voltage sampling unit (112) and time data obtained from the time control unit (113). Specifically, the MCU (110) calculates the effective capacity (Ceff) or the voltage rise rate (△V / △t) using the voltage change amount (△V) and the time change amount (△t), and determines whether the battery is degraded by comparing this with a preset threshold value. The MCU (110) may further include a diagnosis judgment unit (not shown) and a storage unit (memory), the diagnosis judgment unit (not shown) determines whether degradation is present by comparing the calculated value with the threshold value, and the storage unit (not shown) stores the diagnosis result.

[0061] The upper battery (120) is labeled as 12V BAT (Vh) and is the upper battery of two batteries connected in series. The upper battery (120) is connected in series with the lower battery (130) to form the total voltage (Vin).

[0062] The lower battery (130) is labeled as 12V BAT(Vl) and is the battery located at the bottom of two batteries connected in series. The lower battery (130) can be charged by receiving current from the BEQ and is the battery to be diagnosed in this embodiment.

[0063] The upper battery (120) and the lower battery (130) are connected in series to generate a total voltage Vin = Vh + Vl. The MCU (110) measures this total voltage and calculates a reference voltage Vref = Vin / 2. If the voltage (Vl) of the lower battery (130) is lower than the reference voltage (Vref), the BEQ supplies current to the lower battery (130) to balance the voltage.

[0064] The 24V load (140) is a load that uses 24V power supplied through the series connection of the upper battery (120) and the lower battery (130). The 24V load (140) is a major electrical device of a commercial vehicle and may include, for example, a starter motor, a large lamp, etc.

[0065] The 12V load (150) is a load that receives 12V power from the lower battery (130). The 12V load (150) is an auxiliary electrical device in the vehicle, and may include, for example, an interior light, an instrument panel, an audio system, etc.

[0066] The battery condition diagnostic device according to the present embodiment can diagnose the condition of the battery using the MCU (110) included in the BEQ even in a commercial vehicle environment where a BMS is not applied. Through this, it is possible to detect battery degradation without additional hardware and notify the user when maintenance is required.

[0067] (Example 1)

[0068] FIG. 2 is a flowchart illustrating a battery condition diagnosis method according to an embodiment of the present invention.

[0069] Referring to FIG. 2, the MCU (110) measures the voltage of the upper battery (120) and the lower battery (130) through the voltage sampling unit (112) (S101).

[0070] Specifically, the voltage sampling unit (112) uses an ADC to convert the voltage (Vh) of the upper battery (120) and the voltage (Vl) of the lower battery (130) from analog signals into digital signals and transmits them to the MCU (110).

[0071] Next, the MCU (110) calculates the total voltage (Vin) and the reference voltage (Vref) using the measured voltage data (S102). The total voltage (Vin) is calculated as Vin = Vh + Vl, and the reference voltage (Vref) is calculated as Vref = Vin / 2. Here, Vh represents the voltage of the upper battery (120), and Vl represents the voltage of the lower battery (130).

[0072] Next, the MCU (110) determines whether the voltage (Vl) of the lower battery (130) is lower than the reference voltage (Vref) (S103). This determination in step S103 is a process of checking whether a voltage imbalance has occurred between batteries and serves as a criterion for determining whether to start the charging operation of the BEQ.

[0073] If, as a result of the judgment in step S103, the voltage (Vl) of the lower battery (130) is lower than the reference voltage (Vref), BEQ starts supplying current to the lower battery (130) (S104). BEQ operates a DC-DC converter to receive energy from the upper battery (120) and supplies current to the lower battery (130). On the other hand, if the voltage (Vl) of the lower battery (130) is higher than the reference voltage (Vref), it is determined that the voltage is balanced, and the process can be terminated without performing a charging operation.

[0074] When current supply begins, the MCU (110) measures the initial voltage (V0) through the voltage sampling unit (112) and initializes the timer through the time control unit (113) (S105). The initial voltage (V0) refers to the voltage value of the lower battery (130) at the time of charging start and is used as a reference value for calculating the voltage change amount thereafter. Timer initialization means that the time control unit (113) sets the elapsed time to 0.

[0075] After that, the MCU (110) measures the voltage (V1) through the voltage sampling unit (112) after a preset time (△t) has elapsed (S106). The preset time (△t) can be set, for example, 1 second, 2 seconds, etc., and the time control unit (113) monitors whether this time has elapsed.

[0076] Next, the MCU (110) calculates the voltage change amount (△V) (S107). The voltage change amount (△V) is calculated as △V = V1 - V0. Here, V1 is the voltage of the lower battery (130) measured after a preset time has elapsed, and V0 is the initial voltage of the lower battery (130) at the start of charging. The larger the voltage change amount (△V), the more the battery is being charged normally.

[0077] Next, the MCU (110) calculates the effective capacity or voltage rise rate (S108). The effective capacity (Ceff) can be calculated as Ceff = I × △t / △V, where I represents the current value supplied by the BEQ to the lower battery (130), △t represents the change in time, and △V represents the change in voltage. The current value I may be set to a fixed value in the DC-DC converter of the BEQ or may be a value that can be estimated from the circuit structure. Additionally, the MCU (110) may calculate the voltage rise rate (△V / △t) instead of the effective capacity.

[0078] Next, the MCU (110) compares the calculated value with a threshold value to determine whether it is degraded (S109). For example, if the effective capacity (Ceff) is less than 50% of the rated capacity, or if the voltage rise rate (△V / △t) is less than the reference rise rate (e.g., 0.3V / 1s), the MCU (110) may determine that the battery is degraded. The threshold value may be pre-set according to the type and specifications of the battery.

[0079] If, as a result of the judgment in step S109, it is determined that the battery is degraded, the MCU (110) generates a warning flag (S110). The warning flag is a digital signal indicating the degraded state of the battery and can be stored in memory inside the MCU (110).

[0080] Finally, the MCU (110) stores the diagnostic result through the communication unit (111) and transmits it externally (S111). The diagnostic result can be stored in an EEPROM (Electrically Erasable Programmable Read-Only Memory) or flash memory inside the MCU (110), and the communication unit (111) can transmit the diagnostic result to a higher-level control unit or maintenance equipment of the vehicle through interfaces such as CAN, UART, and GPIO (General Purpose Input / Output). In addition, the diagnostic result can be visually or audibly notified to the user in the form of LED flashing, warning sounds, etc.

[0081] The battery status diagnosis method according to the present embodiment can diagnose the battery status without additional sensors by utilizing the existing charging operation of the BEQ, so that battery management functions can be implemented at a low cost.

[0082] (Example 2)

[0083] FIG. 3 is a flowchart illustrating a battery condition diagnosis method according to another embodiment of the present invention, showing a method to improve diagnosis reliability through multiple interval measurements and statistical processing.

[0084] Referring to Fig. 3, it starts similarly to the basic diagnostic method of Fig. 2, but differs in that it additionally performs multiple interval measurements and statistical processing.

[0085] First, the MCU (110) measures the voltage of the upper battery (120) and the lower battery (130) through the voltage sampling unit (112) (S201). This step is the same as step S101 of FIG. 2.

[0086] Next, the MCU (110) determines the charging condition (S202). Specifically, the MCU (110) determines whether the voltage (Vl) of the lower battery (130) is lower than the reference voltage (Vref). The reference voltage (Vref) is calculated as half the value of the total voltage (Vin), which is the same process as steps S102 and S103 of FIG. 2.

[0087] If the result of the judgment in step S202 is that the charging condition is not satisfied (i.e., Vl ≥ Vref), the process is terminated, and if the charging condition is satisfied (i.e., Vl < Vref), the process proceeds to the next step.

[0088] When the charging condition is met, the BEQ starts supplying current to the lower battery (130), and the MCU (110) sets multiple time intervals (S203). For example, the MCU (110) can set multiple different time intervals such as 0.5 seconds, 1 second, 2 seconds, and 3 seconds. These multiple time interval settings are intended to reduce measurement error and increase the reliability of the diagnosis compared to a single point-in-time measurement.

[0089] After that, the MCU (110) measures the voltage for each time interval and calculates the △V / △t value (S204). Specifically, the MCU (110) measures the voltage (V1, V2, V3, V4) for each time interval (e.g., 0.5 seconds, 1 second, 2 seconds, 3 seconds) based on the initial voltage (V0) at the start of charging, and calculates the voltage change amount (△V1, △V2, △V3, △V4) and voltage rise rate (△V1 / △t1, △V2 / △t2, △V3 / △t3, △V4 / △t4) for each interval. This calculation can be repeated n times.

[0090] Next, the MCU (110) performs statistical processing on the multiple measured △V / △t values ​​(S205). Statistical processing may include calculating the mean value, calculating the standard deviation, and calculating the coefficient of variation (the standard deviation divided by the mean). The mean value indicates the central tendency of the multiple measurements, the standard deviation indicates the degree of dispersion of the measurements, and the coefficient of variation indicates the relative variability of the measurements.

[0091] Next, the MCU (110) compares the average value with the threshold value and evaluates the reliability using the coefficient of variation (S206). If the average value is lower than the threshold value, it can be seen that the battery performance has deteriorated, but if the coefficient of variation is large, it means that the measurement reliability is low, so the two factors are considered together to make a comprehensive judgment.

[0092] Next, the MCU (110) determines that the battery is degraded if the reliability is above a standard and the average value is below a threshold value (S207). For example, if the measurement reliability is high with a coefficient of variation of 10% or less and the average voltage rise rate is below a threshold value (e.g., 0.3V / 1s), the MCU (110) can determine that the battery is degraded.

[0093] If degradation is determined, the MCU (110) increases the diagnosis result accumulation count (S208). The accumulation count records the number of times degradation is determined and is used to distinguish between temporary measurement errors and actual battery degradation.

[0094] Next, the MCU (110) determines whether the accumulated count exceeds a preset number of times (S209). For example, if the preset number of times is set to 3, a definite warning is generated when the degradation judgment accumulates 3 or more times. This is a method to exclude one-time errors and only warn of continuous battery degradation.

[0095] When the accumulated count exceeds a preset number of times, the MCU (110) generates a confirmation warning (S209). The confirmation warning is a warning signal that clearly informs the user that a battery replacement or inspection is required.

[0096] Finally, the MCU (110) stores the diagnostic result through the communication unit (111) and transmits it externally (S210). This step is the same as step S111 of FIG. 2.

[0097] The battery condition diagnosis method according to the present embodiment can significantly improve the accuracy and reliability of the diagnosis compared to a single measurement through multiple interval measurements and statistical processing.

[0098] (Example 3)

[0099] FIG. 4 is a flowchart illustrating a battery status diagnosis method according to another embodiment of the present invention, showing a self-learning-based adaptive diagnosis method.

[0100] Referring to FIG. 4, the present embodiment is a method for automatically learning individual characteristics of a battery to generate an adaptive reference value and diagnosing the battery condition based thereon.

[0101] First, the MCU (110) detects the installation of a new battery (S301). The detection of a new battery installation can be achieved through a sudden change in the voltage pattern, input of a reset signal by the user, or a preset initialization procedure. The MCU (110) monitors the battery voltage through the voltage sampling unit (112), and when it is determined that a new battery has been installed, it starts an initial learning process.

[0102] When a new battery is detected, the MCU (110) enters an initial learning mode (S302). The initial learning mode is a mode for identifying the unique characteristics of the new battery, and in this mode, the focus is on data collection rather than diagnosis.

[0103] In the initial learning mode, the MCU (110) collects voltage change data during multiple charging processes (S303). For example, the MCU (110) collects and stores data such as voltage change amount (△V), time change amount (△t), and voltage rise rate (△V / △t) for each cycle during 10 or more charging cycles. These multiple measurements are intended to identify consistent characteristics of the battery and exclude accidental fluctuations.

[0104] When data collection is complete, the MCU (110) generates a reference profile from the collected data (S304). The reference profile includes an average △V / △t value, a normal range (average ± standard deviation), etc., and is a reference value that reflects the individual characteristics of the battery. For example, if the average voltage rise rate of the battery is 0.5V / 1s and the standard deviation is 0.05V / 1s, the normal range can be set to 0.45V / 1s ~ 0.55V / 1s.

[0105] The generated reference profile is stored in memory inside the MCU (110) (S305). The storage is performed in non-volatile memory such as EEPROM or flash memory so that the data is retained even when the power is turned off.

[0106] When the reference profile saving is complete, the MCU (110) switches to normal operation mode (S306). Normal operation mode is a mode that performs actual battery status diagnosis after learning is complete.

[0107] In normal operation mode, the MCU (110) performs periodic diagnosis (S307). Periodic diagnosis may be performed, for example, once a day, once a week, or whenever a charging cycle occurs. The MCU (110) measures the current △V / △t value in a manner similar to the method described in FIG. 2.

[0108] After performing the diagnosis, the MCU (110) calculates the deviation relative to the reference profile (S308). The deviation is the difference between the currently measured △V / △t value and the average value of the reference profile expressed as a percentage. For example, if the average voltage rise rate of the reference profile is 0.5V / 1s and the current measured value is 0.4V / 1s, the deviation is (0.5-0.4) / 0.5 × 100 = 20%.

[0109] Next, the MCU (110) determines whether the deviation exceeds an allowable range and, if it exceeds it, generates a step-by-step warning (S309). Specifically, if the deviation exceeds 20%, a first warning is generated; if it exceeds 40%, a second warning is generated; and if it exceeds 60%, a replacement recommendation warning is generated. These step-by-step warnings progressively inform the user of the severity of the battery condition and provide time to take appropriate action.

[0110] Next, the MCU (110) gradually updates the reference profile based on long-term usage data (S310). Since the battery naturally ages over time, the MCU (110) can gradually adjust the reference profile to reflect this aging trend. For example, if data collected over one year is analyzed and a trend is found where the average voltage increase rate decreases by 5% per year, the reference profile is updated to reflect this. This allows for distinguishing between rapid degradation and gradual aging.

[0111] After that, the MCU (110) stores and transmits diagnostic results and trend information through the communication unit (111) (S311). The trend information is data indicating changes in battery performance over time, which can help users or maintenance personnel predict the remaining lifespan of the battery.

[0112] Finally, the MCU (110) waits until the next diagnostic cycle (S312). Once the waiting period has elapsed, it returns to step S307 to repeat the periodic diagnosis. Through this repeated diagnosis, the battery status can be continuously monitored.

[0113] The battery condition diagnosis method according to the present embodiment automatically learns the individual characteristics of the battery and uses adaptive reference values, so it can be universally applied regardless of the battery type or manufacturer, and the diagnostic accuracy can be significantly improved compared to a method using a fixed threshold value.

[0114] As described above, this embodiment enables the diagnosis of battery degradation using only a battery equalizer without a BMS, thereby providing a battery management solution suitable for commercial vehicle environments where the application of a BMS is difficult. Furthermore, this embodiment enables the addition of a battery condition diagnosis function without the need for separate circuits or expensive sensors, thus enabling the implementation of battery management functions at a low cost. Additionally, this embodiment enables the early detection of increases in internal resistance and decreases in capacity, thereby preventing battery failure at an early stage. Moreover, this embodiment enables the determination of battery replacement based on diagnostic data, allowing for the reasonable setting of maintenance cycles and the improvement of maintenance efficiency. Furthermore, this embodiment enables the prevention of reduced system efficiency and safety through the early identification of degraded batteries.

[0115] Although the present invention has been described with reference to the embodiments illustrated in the drawings, this is merely illustrative, and those skilled in the art will understand that various modifications and equivalent alternative embodiments are possible therefrom. Accordingly, the technical scope of protection of the present invention should be determined by the claims below. Furthermore, the implementations described herein may be implemented, for example, as methods or processes, devices, software programs, data streams, or signals. Even if discussed only in the context of a single form of implementation (e.g., discussed only as a method), the implementation of the discussed features may also be implemented in other forms (e.g., devices or programs). Devices may be implemented in appropriate hardware, software, and firmware, etc. Methods may be implemented in devices such as processors, which generally refer to processing devices including, for example, computers, microprocessors, integrated circuits, or programmable logic devices. Processors also include communication devices such as computers, cell phones, portable / personal digital assistants ("PDAs"), and other devices that facilitate the communication of information between end-users. Explanation of the symbols

[0117] 10: Vehicle System 110 : Microcontroller Unit (MCU) 111 : Communications Department 112 : Voltage sampling section 113 : Time control unit 120: Top Battery 130: Sub-battery 140: 24V load 150: 12V load

Claims

Claim 1 A battery condition diagnosis device comprising: a voltage sampling unit for measuring the voltage of an upper battery and a lower battery connected in series; a time control unit for measuring the elapsed time from the start of current supply; a communication unit for transmitting and receiving data with an external device; and a microcontroller unit for diagnosing the condition of the battery using voltage data measured from the voltage sampling unit and time data obtained from the time control unit; wherein the microcontroller unit supplies current to the lower battery when the voltage of the lower battery is lower than a reference voltage, calculates the effective capacity or voltage rise rate using the voltage change amount and the time change amount, and determines whether the battery is degraded by comparing the calculated value with a threshold value. Claim 2 A battery condition diagnostic device according to claim 1, wherein the voltage sampling unit comprises an Analog to Digital Converter (ADC) that converts an analog signal into a digital signal. Claim 3 A battery condition diagnostic device according to claim 1, wherein the microcontroller unit calculates the total voltage by adding the voltage of the upper battery and the voltage of the lower battery, and calculates the reference voltage by dividing the total voltage by 2. Claim 4 A battery condition diagnostic device according to claim 1, wherein the microcontroller unit further comprises a memory for storing diagnostic results. Claim 5 A battery status diagnostic device according to claim 1, wherein the communication unit transmits a diagnostic result through at least one communication interface among CAN (Controller Area Network), UART (Universal Asynchronous Receiver / Transmitter), or GPIO (General Purpose Input / Output). Claim 6 A battery condition diagnosis method characterized by comprising: a step in which a microcontroller unit measures the voltages of an upper battery and a lower battery through a voltage sampling unit; a step in which the microcontroller unit calculates a total voltage and a reference voltage using the measured voltage data; a step in which the microcontroller unit determines whether the voltage of the lower battery is lower than the reference voltage; a step in which, if the result of the determination is that the voltage of the lower battery is lower than the reference voltage, the microcontroller unit starts supplying current to the lower battery; a step in which the microcontroller unit measures an initial voltage and initializes a timer; a step in which the microcontroller unit measures the voltage after a preset time has elapsed; a step in which the microcontroller unit calculates the voltage change amount; a step in which the microcontroller unit calculates the effective capacity or the voltage rise rate; a step in which the microcontroller unit determines whether degradation has occurred by comparing the calculated value with a threshold value; and a step in which, if degradation is determined in the step of determining whether degradation has occurred, the microcontroller unit generates a warning flag and stores and transmits the diagnosis result. Claim 7 A battery condition diagnosis method according to claim 6, wherein the step of calculating the effective capacity or voltage rise rate is characterized by the microcontroller unit calculating the effective capacity by dividing the value obtained by multiplying the supply current value and the time change amount by the voltage change amount. Claim 8 A battery condition diagnosis method according to claim 6, wherein the step of determining whether degradation has occurred is characterized in that the microcontroller unit determines that the battery is degraded when the effective capacity is less than 50% of the rated capacity or when the voltage rise rate is less than a reference rise rate. Claim 9 A battery condition diagnosis method characterized by comprising: a step in which a microcontroller unit measures the voltage of an upper battery and a lower battery; a step in which the microcontroller unit determines whether the voltage of the lower battery is lower than a reference voltage; a step in which, if the result of the determination is that the voltage of the lower battery is lower than the reference voltage, the microcontroller unit starts supplying current to the lower battery and sets a plurality of time intervals; a step in which the microcontroller unit measures the voltage for each time interval and calculates a voltage rise rate value; a step in which the microcontroller unit performs statistical processing on the measured plurality of voltage rise rate values; a step in which the microcontroller unit compares an average value with a threshold value and evaluates reliability using a coefficient of variation; a step in which, if the reliability is above a reference and the average value is below the threshold value, the microcontroller unit determines that there is degradation; a step in which the microcontroller unit increases the accumulated count of the diagnosis result; and a step in which, if the accumulated count exceeds a preset number of times, the microcontroller unit generates a confirmed warning. Claim 10 A battery condition diagnosis method according to claim 9, wherein the step of performing the statistical processing is characterized in that the microcontroller unit calculates the average value, standard deviation, and coefficient of variation for the plurality of voltage rise rate values. Claim 11 A battery condition diagnosis method characterized by comprising: a step in which a microcontroller unit detects the installation of a new battery; a step in which the microcontroller unit enters an initial learning mode; a step in which the microcontroller unit collects voltage change data during a multiple charging process; a step in which the microcontroller unit generates a reference profile including an average voltage rise rate value and a normal range from the collected data; a step in which the microcontroller unit stores the reference profile in memory; a step in which the microcontroller unit switches to a normal operation mode; a step in which the microcontroller unit periodically performs a diagnosis to measure the current voltage rise rate value; a step in which the microcontroller unit calculates a deviation from the reference profile; and a step in which, if the deviation exceeds an allowable range, the microcontroller unit generates a step-by-step warning. Claim 12 A battery condition diagnosis method according to claim 11, further comprising the step of the microcontroller unit progressively updating the reference profile based on long-term usage data.

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