Battery state diagnosis device and method

Abstract

The battery state diagnosis device and method according to the embodiments and experimental examples of the present invention monitor the charging voltage and charging time of the battery, and diagnose the abnormal state of the battery that occurs as a precursor before the battery catches fire, thereby enabling safe use of the battery.

Description

Technical Field

[0001] This application claims the benefit of the filing date of Korean Patent Application No. 10-2023-0017802, filed with the Korean Intellectual Property Office on February 10, 2023, and all of the contents disclosed in the document of the Korean patent application are incorporated herein.

[0002] The present invention relates to a battery state diagnosis device and method, and more specifically, to a battery state diagnosis device and method for diagnosing an abnormal state of a battery by monitoring a charging voltage and a charging time during a charging cycle of the battery.

Background Art

[0003] As fossil fuels are depleted and interest in environmental pollution increases, the importance of environmentally friendly alternative energy sources is becoming increasingly significant. Among various alternative energy sources, the demand for rechargeable lithium secondary batteries is rapidly increasing.

[0004] Lithium secondary batteries are applied to many industrial fields such as mobile application devices, automobiles, robots, and energy storage devices as countermeasures against environmental regulations and high crude oil prices. However, since lithium secondary batteries pose a risk of ignition or explosion when internal or external defects occur, it is important to diagnose their state in real time.

[0005] Therefore, conventionally, in order to diagnose an abnormal state of a battery, the strength of the voltage and the temperature have been monitored.

[0006] However, the conventional battery state diagnosis method has a disadvantage in that the measured values are likely to vary due to peripheral environmental factors.

Summary of the Invention

Problems to be Solved by the Invention

[0007] An object of the present invention for solving the above problems is to provide a battery state diagnosis device.

[0008] Another object of the present invention for solving the above problems is to provide a battery state diagnosis method.

Means for Solving the Problems

[0009] A battery state diagnosis apparatus according to an embodiment of the present invention for achieving the above object includes a memory and a processor that executes at least one instruction in the memory. The at least one instruction includes an instruction for monitoring whether there is a specific cycle in which an abnormality occurs in a voltage measurement value among charging cycles of a battery, an instruction for confirming a charging time of the battery in the next cycle that proceeds after the specific cycle, and an instruction for diagnosing an abnormal state of the battery based on the charging time of the battery in the next cycle.

[0010] At this time, the charging time can include a first charging time that is a time for charging the battery in a constant current (CC) charging method and a second charging time that is a time for charging the battery in a constant voltage (CV) charging method.

[0011] On the other hand, the instruction for diagnosing the abnormal state of the battery can include an instruction for comparing the charging time in the specific cycle with the charging time in the next cycle and diagnosing the abnormal state of the battery.

[0012] More specifically, the instruction for diagnosing the abnormal state of the battery includes an instruction for determining that an abnormality has occurred in the battery if the constant current (CC) charging time in the next cycle with respect to the specific cycle increases by a first threshold value or more defined in advance or the constant voltage (CV) charging time in the next cycle with respect to the specific cycle decreases by a second threshold value or less defined in advance.

[0013] In addition, the instruction for diagnosing the abnormal state of the battery may include an instruction for diagnosing that an abnormality has occurred in the battery if the constant current (CC) charging time in the next cycle with respect to the specific cycle increases by a predefined first threshold or more, and the constant voltage (CV) charging time in the next cycle with respect to the specific cycle decreases by a predefined second threshold or less.

[0014] On the other hand, the monitoring instruction may include an instruction for obtaining a plurality of open circuit voltage (OCV) measurement values measured for each charging cycle, an instruction for monitoring whether there is at least one of the OCV measurement values having a change amount greater than or equal to a predefined threshold with respect to the OCV measurement value in the immediately preceding cycle among the plurality of OCV measurement values, and an instruction for determining the cycle in which at least one of the OCV measurement values is measured as the specific cycle.

[0015] In addition, the abnormal state of the battery may include a state of fire risk of the battery or a state in which venting of the battery occurs.

[0016] And the battery state diagnosis device may further include an instruction for counting the number of times of diagnosing the abnormal state of the battery, and an instruction for outputting an alarm when the counted number of times of diagnosing the abnormal state is equal to or greater than a predefined threshold.

[0017] A battery state diagnosis method by a battery state diagnosis device according to another embodiment of the present invention for achieving the above object includes a step of monitoring whether there is a specific cycle in which an abnormality occurs in a voltage measurement value among charging cycles of a battery, a step of checking a charging time of the battery in the next cycle that proceeds after the specific cycle, and a step of diagnosing an abnormal state of the battery based on the charging time of the battery in the next cycle.

[0018] At this time, the charging time can include a first charging time which is the time for charging the battery in a constant current (CC) charging mode, and a second charging time which is the time for charging the battery in a constant voltage (CV) charging mode.

[0019] On the other hand, the step of diagnosing an abnormal state of the battery can include a step of comparing the charging time in the specific cycle with the charging time in the next cycle to diagnose the abnormal state of the battery.

[0020] More specifically, the step of diagnosing an abnormal state of the battery can include a step of determining that an abnormality has occurred in the battery if the constant current (CC) charging time in the next cycle increases by a predefined first threshold value or more with respect to the specific cycle, or if the constant voltage (CV) charging time in the next cycle decreases by a predefined second threshold value or less with respect to the specific cycle.

[0021] Also, the step of diagnosing an abnormal state of the battery can include a step of diagnosing that an abnormality has occurred in the battery if the constant current (CC) charging time in the next cycle increases by a predefined first threshold value or more with respect to the specific cycle and the constant voltage (CV) charging time in the next cycle decreases by a predefined second threshold value or less with respect to the specific cycle.

[0022] On the other hand, the monitoring step can include a step of obtaining a plurality of open circuit voltage (OCV) measurement values measured for each charging cycle, a step of monitoring whether there is at least one OCV measurement value having a change amount greater than or equal to a predefined threshold value with respect to the OCV measurement value in the previous cycle among the plurality of OCV measurement values, and a step of determining the cycle in which at least one of the OCV measurement values is measured as the specific cycle.

[0023] The abnormal state of the battery may include a risk of fire of the battery or a venting state of the battery.

[0024] The battery status diagnosis method may further include a step of counting the number of abnormal state diagnosis of the battery, and a step of outputting an alarm when the counted number of abnormal state diagnosis is equal to or greater than a predefined threshold value. Effect of the Invention

[0025] The battery state diagnosis device and method according to the embodiments and experimental examples of the present invention can provide a battery state diagnosis device and method with improved safety by diagnosing damage to a battery caused by an external impact. [Brief description of the drawings]

[0026]

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Embodiments for Carrying Out the Invention

[0027] Since the present invention can be modified in various ways and can have various embodiments, specific embodiments will be illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, but should be understood to include all modifications, equivalents or alternatives included in the spirit and technical scope of the present invention. Similar reference numerals are used for similar components while explaining each drawing.

[0028] Terms such as first, second, A, B, etc. can be used to describe various components, but the above components should not be limited by the above terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the rights of the present invention, the first component can be named the second component, and similarly the second component can be named the first component. The term "and / or" includes a combination of a plurality of relatedly described items or one of a plurality of relatedly described items.

[0029] When it is mentioned that a certain component is "connected to" or "connected with" another component, it should be understood that it may be directly connected or connected to the other component, but there may also be another component in the middle. On the contrary, when it is mentioned that a certain component is "directly connected to" or "directly connected with" another component, it should be understood that there is no other component in the middle.

[0030] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as "including" or "having" are intended to specify the presence of the features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and it should be understood that the presence or possibility of addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof is not precluded in advance.

[0031] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention pertains. Terms defined as in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or overly formal sense unless clearly defined in this application.

[0032] Figure 1 is a block diagram of a battery system to which an embodiment of the present invention can be applied.

[0033] Referring to Figure 1, a battery pack or a battery module can be configured to include a plurality of battery cells connected in series. The battery cell or module can be connected to a load via a positive terminal and a negative terminal to perform charge and discharge operations. The most commonly used battery cell is a lithium-ion (Li-Ion) battery cell.

[0034] Such a battery cell or battery module can be interlocked with a battery management system (BMS).

[0035] The battery management system (BMS) can monitor the current, voltage, and temperature of each battery cell or module it manages, calculate the SOC (State Of Charge) based on the monitoring results, and control charging and discharging. Here, SOC (State of Charge; charge rate) represents the current charged state of the battery as a percentage [%], and SOH (State of Health; battery life state) represents the current degradation state of the battery as a percentage [%].

[0036] In this way, the battery management system (BMS) can read the cell voltage while monitoring the battery cells and transmit it to other systems connected to the battery.

[0037] In addition, the battery management system (BMS) can monitor at least one electrical component constituting the battery system and transmit this status data to other devices. For this purpose, the battery management system (BMS) can include a communication module for communicating with other devices within the device included in the battery system.

[0038] The communication module of the battery management system (BMS) can communicate with other systems within the device using CAN (Controller Area Network). In this case, the electrical components, modules, or systems within the battery management system (BMS) are connected to each other via the CAN bus. As a result, the battery management system (BMS) can remotely transmit the status data obtained through the monitoring of the battery pack or module and at least one electrical component constituting the battery management system (BMS) to other systems using CAN communication.

[0039] On the other hand, the battery management system (BMS) balances the charge of the battery cells evenly to extend the life of the battery system.

[0040] To perform such operations, the battery management system (BMS) can include various components such as fuses, current sensing elements, thermistors, switches, balancers, etc. In most cases, however, it further includes an MCU (Micro Controller Unit) or BMIC (Battery Monitoring Integrated Chip) for controlling in conjunction with these components. Here, the BMIC may be a component in the form of an IC located inside the battery management system (BMS) that measures information such as the voltage, temperature, and current of the battery cell / module. According to an embodiment, the battery management system (BMS) can be applied to an automobile.

[0041] On the other hand, generally, the battery management system (BMS) operates in conjunction with a battery protection device to cut off the charge and discharge circuit by the battery protection device when an abnormality occurs in the battery. In other words, the conventional battery protection circuit restricts the use of the battery by cutting off the charge and discharge circuit when an abnormality occurs in any one battery cell or module.

[0042] The battery state diagnosis device according to an embodiment of the present invention can be embodied as being included in the configuration of the battery management system (BMS).

[0043] Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

[0044] FIG. 2 is a block diagram of a battery state diagnosis device according to an embodiment of the present invention.

[0045] The battery state diagnosis device 1000 may be a device that pre-diagnoses an abnormal state of the battery in order to prevent ignition of the battery. In other words, the battery state diagnosis device 1000 may be a device that senses abnormal phenomena of the battery that occur as pre-symptoms before ignition due to thermal runaway of the battery. For example, the abnormal phenomenon may be a vent phenomenon.

[0046] According to an embodiment, the battery state diagnosis device 1000 can monitor the charging voltage values acquired for each cycle and obtain specific cycle information in which an abnormality has occurred in the charging voltage value. Thereafter, the battery state diagnosis device 1000 can monitor the charging time in the next cycle based on the specific cycle and determine that an abnormal phenomenon has occurred in the battery.

[0047] Referring to FIG. 2, if the battery state diagnosis device 1000 is described in more detail by configuration, the battery state diagnosis device 1000 may include a memory 100, a processor 200, a transceiver 300, an input interface device 400, an output interface device 500, and a storage device 600.

[0048] According to an embodiment, each component 100, 200, 300, 400, 500, 600 included in the battery state diagnosis device 1000 can be connected by a bus 700 and communicate with each other.

[0049] Among the above components 100, 200, 300, 400, 500, 600, the memory 100 and the storage device 600 can be composed of at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory 100 and the storage device 600 can be composed of at least one of a read only memory (ROM) and a random access memory (RAM).

[0050] Among these, the memory 100 can include at least one instruction executed by the processor 200.

[0051] According to an embodiment, the at least one instruction includes an instruction to monitor whether there is a specific cycle in which an abnormality occurs in the voltage measurement value among the charging cycles of the battery, an instruction to confirm the charging time of the battery in the next cycle that proceeds after the specific cycle, and an instruction to diagnose an abnormal state of the battery based on the charging time of the battery in the next cycle.

[0052] At this time, the charging time may include a first charging time which is the time for charging the battery in a constant current (CC) charging mode, and a second charging time which is the time for charging the battery in a constant voltage (CV) charging mode.

[0053] On the other hand, the instruction for diagnosing the abnormal state of the battery may include an instruction for diagnosing the abnormal state of the battery by comparing the charging time in the specific cycle with the charging time in the next cycle.

[0054] More specifically, the instruction for diagnosing the abnormal state of the battery may include an instruction for determining that an abnormality has occurred in the battery if the constant current (CC) charging time in the next cycle for the specific cycle increases by a first threshold value or more defined in advance, or if the constant voltage (CV) charging time in the next cycle for the specific cycle decreases by a second threshold value or less defined in advance.

[0055] Also, the instruction for diagnosing the abnormal state of the battery may include an instruction for diagnosing that an abnormality has occurred in the battery if the constant current (CC) charging time in the next cycle for the specific cycle increases by a first threshold value or more defined in advance, and if the constant voltage (CV) charging time in the next cycle for the specific cycle decreases by a second threshold value or less defined in advance.

[0056] On the other hand, the monitoring instruction may include an instruction for obtaining a plurality of open circuit voltage (OCV) measurement values measured for each charging cycle, an instruction for monitoring whether there is at least one OCV measurement value having a change amount greater than or equal to a threshold value defined in advance with respect to the OCV measurement value in the immediately previous cycle among the plurality of OCV measurement values, and an instruction for determining the cycle in which at least one of the OCV measurement values is measured as the specific cycle.

[0057] Further, the abnormal state of the battery can include a state of risk of ignition of the battery or a state in which venting of the battery occurs.

[0058] And the battery state diagnosis device can further include an instruction to count the number of times of diagnosing the abnormal state of the battery, and an instruction to output an alarm when the counted number of times of diagnosing the abnormal state is equal to or greater than a predefined threshold value.

[0059] On the other hand, the processor 200 can mean a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor in which the method according to the embodiment of the present invention is performed.

[0060] As described above, the processor 200 can execute at least one program command stored in the memory 100.

[0061] Above, the battery state diagnosis device according to the embodiment of the present invention has been described. Hereinafter, a battery state diagnosis method performed by a process operation in the battery state diagnosis device will be described.

[0062] FIG. 3 is a flowchart for explaining a battery state diagnosis method according to an embodiment of the present invention, and FIG. 4 is a graph showing changes in the magnitude of the charging voltage over time for each charging cycle of the battery according to an embodiment of the present invention.

[0063] Referring to FIGS. 3 and 4, the battery state diagnosis device 1000 can obtain a charging voltage value for each charging cycle of the battery (S1000). According to an embodiment, the charging voltage value may be data measured by the battery state diagnosis device 1000 for each charging cycle or data received from an external device.

[0064] Thereafter, the battery state diagnosis device 1000 can monitor whether a measurement abnormality has occurred in the measured values of the charging voltage values acquired for each cycle, and acquire specific cycle information in which the charging voltage value with the abnormality has occurred (S2000).

[0065] According to the embodiment, when there is a charging voltage value among the plurality of charging voltage values measured for each cycle that has a change amount equal to or greater than a predefined threshold value with respect to the charging voltage value in the immediately preceding cycle, the battery state diagnosis device 1000 can determine that an abnormality has occurred in the corresponding charging voltage value. Thereafter, the battery state diagnosis device 1000 can acquire specific cycle information in which the corresponding charging voltage value has been measured. For example, the charging voltage value may be a charging OCV (Open Circuit Voltage) value. Here, the charging OCV may be a voltage measured when no current flows through the battery in the charged state.

[0066] In other words, when there is an OCV value among the plurality of OCV values measured for each cycle that has a change amount equal to or greater than a predefined threshold value with respect to the OCV value in the immediately preceding cycle, the battery state diagnosis device 1000 can determine that an abnormality has occurred in the corresponding OCV value. Thereafter, the battery state diagnosis device 1000 can acquire specific cycle information in which the corresponding OCV value has been measured. For example, the predefined threshold value may be 0.0001V.

[0067] Thereafter, the battery state diagnosis device 1000 can confirm the charging time in the next cycle based on the specific cycle (S3000). In other words, when the specific cycle is N Cycle, the battery state diagnosis device 1000 can confirm the charging time of the battery in N+1 Cycle.

[0068] Here, the charging time can include a first charging time and a second charging time. According to one embodiment, the first charging time may be the time for charging the battery in a constant current (CC) charging mode. According to another embodiment, it can include the first charging time and a second charging time which is the time for charging the battery in a constant voltage (CV) charging mode.

[0069] In other words, the battery state diagnosis device 1000 can diagnose an abnormal state of the battery by using at least one of the first charging time and the second charging time of the next cycle (N + 1 Cycle) based on the above specific cycle (N Cycle) (S4000).

[0070] According to one embodiment, when the first charging time in the next cycle (N + 1 Cycle) increases by more than a predefined first threshold value or the second charging time decreases by less than a predefined second threshold value based on the above specific cycle (N Cycle), the battery state diagnosis device 1000 can determine that an abnormal phenomenon has occurred in the battery.

[0071] According to another embodiment, when the first charging time in the next cycle (N + 1 Cycle) increases by more than a predefined first threshold value and the second charging time decreases by less than a predefined second threshold value based on the above specific cycle (N Cycle), the battery state diagnosis device 1000 can determine that an abnormal phenomenon has occurred in the battery.

[0072] Here, the abnormal phenomenon of the battery may be a gas ejection phenomenon that occurs before the battery catches fire due to thermal runaway.

[0073] Thereby, the battery state diagnosis device 1000 can diagnose an abnormal state of the battery that occurs as a precursor before the battery catches fire due to thermal runaway. Therefore, the battery state diagnosis device 1000 can provide a battery usage environment with improved safety.

[0074] Thereafter, the battery state diagnostic device 1000 can count the number of times the abnormal state diagnosis has been performed while repeatedly performing steps S1000 to S4000.

[0075] Thereafter, if the number of times (C) that the abnormal state of the battery has been counted is equal to or greater than K (S5000), battery state diagnosis device 1000 can output an alarm to notify an administrator of a dangerous situation (S6000).

[0076] According to one embodiment, the battery state diagnosis device 1000 can generate an alarm sound to notify a manager of a risk of fire if the number of times the battery has entered an abnormal state is K or more.

[0077] According to another embodiment, the battery status diagnosis device 1000 can transmit a warning message to an administrator terminal to notify the administrator that a fire danger situation exists if the number of times the battery has entered an abnormal state is K or more.

[0078] However, the battery status diagnosis device 1000 is not limited to the above, and can notify the administrator of a fire danger situation using various methods such as vibration.

[0079] The battery state diagnosis device and method according to the embodiment of the present invention have been described above. Hereinafter, the battery state diagnosis method will be described in more detail based on experimental examples of the present invention.

[0080] FIG. 5 is a graph showing OCV values ​​measured for each charge cycle of a battery according to an embodiment of the present invention, and FIG. 6 is a table summarizing the OCV values ​​measured for each charge cycle of the battery according to FIG. 5.

[0081] Generally, the voltage value of a battery gradually decreases within a preset threshold value as a charging cycle progresses.

[0082] On the other hand, if an abnormality occurs in the battery, the voltage value of the battery may suddenly decrease by a value equal to or greater than the threshold value.

[0083] Therefore, the battery state diagnosis device 1000 can monitor whether there is an OCV value among a plurality of OCV values (OCV_Charge) measured for each cycle that has a change amount (ΔOCV) greater than or equal to a predefined threshold with respect to the OCV value in the previous cycle.

[0084] After that, when there is an OCV value exceeding the above threshold, the battery state diagnosis device 1000 can check the specific cycle information in which the corresponding OCV value was measured.

[0085] Referring to FIG. 5, when the charging cycle of the battery is 58 cycles, it can be confirmed that the OCV value of the battery drops sharply and then recovers sharply at 59 cycles.

[0086] Explaining in more detail with reference to FIG. 6, it can be confirmed that the change amount of OCV in other charging cycles is less than 0.001V, except for the change amount of OCV when the charging cycle of the battery is 58 - 59 cycles.

[0087] For example, when checking the change amount of OCV in cycle 57 immediately before cycle 58, when the charging cycle of the battery is 56 cycles, the OCV value of the battery is 4.17437V, and when the charging cycle of the battery is 57 cycles, the OCV value of the battery is 4.17434V. Therefore, it can be confirmed that the change amount of OCV in cycle 57 is 0.00003V.

[0088] On the other hand, when the charging cycle of the battery is 58 cycles, since the OCV value of the battery is measured as 4.17148V, it can be confirmed that the change amount of OCV in cycle 58 has dropped sharply to 0.00286V with respect to the OCV value in cycle 57 (4.17434V).

[0089] Also, when the charging cycle of the battery is 59 cycles, since the OCV value of the battery is measured as 4.17333V, it can be confirmed that the change amount in cycle 59 has recovered sharply to 0.00185V with respect to the OCV value in cycle 58 (4.17148V).

[0090] Therefore, the battery state diagnosis device 1000 can predict that an abnormality has occurred in the battery at 58 cycles exceeding a predefined threshold. Thus, the battery state diagnosis device 1000 can acquire 58 cycles as specific cycle information. Here, the predefined threshold can be set by the administrator based on the amount of change in OCV measured for each charge cycle. For example, the threshold may be 0.0001V.

[0091] FIG. 7 is a graph showing the first charging time for each charge cycle of the battery in the battery state diagnosis method according to the experimental example of the present invention.

[0092] Referring to FIG. 7, it can be confirmed that at the 59th cycle, which is the cycle following the 58 cycles acquired as specific cycle information in FIG. 5, the first charging time (Chg CC) of the battery dropped sharply.

[0093] Referring to FIG. 6 for a more detailed explanation, it can be confirmed that except for the first charging time (Chg CC) when the battery is at the 59th cycle, the first charging time (Chg CC) at other charge cycles all changed within 30 seconds.

[0094] On the other hand, it was confirmed that the first charging time (Chg CC) at the 58th cycle, which is the specific cycle, took 9254.8 seconds, and the first charging time (Chg CC) at the 59th cycle, which is the next cycle, took 9150.6 seconds. In other words, it can be confirmed that the first charging time (Chg CC) was shortened by 104.2 seconds (△CC) at the 59th cycle compared to the 58th cycle, which was the previous cycle.

[0095] FIG. 8 is a graph showing the second charging time for each charge cycle of the battery in the battery state diagnosis method according to the experimental example of the present invention.

[0096] Referring to FIG. 8, it can be confirmed that in the 59th cycle, which is the next cycle after the 58th cycle obtained as specific cycle information in FIG. 4, the second charging time (Chg CV) of the battery increased rapidly.

[0097] Referring to FIG. 6 for a more detailed description, it can be confirmed that except for the second charging time when the battery is in the 59th cycle, the second charging time (Chg CV) in other charging cycles all changed within 70 seconds.

[0098] On the other hand, it was confirmed that the second charging time (Chg CV) in the 58th cycle, which is a specific cycle, took 1953 seconds, and it was confirmed that the second charging time (Chg CV) in the 59th cycle, which is the next cycle, took 2239 seconds. In other words, it can be confirmed that the second charging time (Chg CV) increased by 286 seconds (△CV) in the 59th cycle compared to the 58th cycle, which is the previous cycle.

[0099] FIG. 9 is a graph showing the change in the magnitude of OCV according to the charging time for each charging cycle of the battery according to the experimental example of the present invention.

[0100] Referring to FIG. 9, based on the 58th cycle, which is a specific cycle, it was confirmed that the first charging time (CC Time) in the 59th cycle, which is the next cycle, decreased by 9150.6 seconds, which is less than or equal to a predefined first threshold value (for example, 100 seconds), compared to the first charging time in the specific cycle.

[0101] Also, based on the 58th cycle, which is a specific cycle, it was confirmed that the second charging time (CV Time) in the 59th cycle, which is the next cycle, increased by 2239 seconds, which is greater than or equal to a predefined second threshold value (for example, 150 seconds), and at this time, it was confirmed that gas ejection (Vent) occurred in the battery.

[0102] Therefore, the battery state diagnosis device 1000 according to the embodiments and experimental examples of the present invention can determine that an abnormal phenomenon has occurred in the battery when the changes in the first charging time (CC Time) and the second charging time (CV Time) in the next cycle based on a specific cycle are each greater than or equal to the first threshold value and the second threshold value.

[0103] On the other hand, not only at 58 cycles, but also when the charging cycle of the battery is 114 cycles, it was confirmed that the OCV value of the battery dropped sharply and then recovered sharply at 115 cycles. In other words, it was confirmed that 114 cycles is also a specific cycle.

[0104] After that, as shown in FIG. 9, not only at 59 cycles, but also at 115 cycles, it was confirmed that the first charging time decreased below the first threshold value and the second charging time increased above the second threshold value, and then it was confirmed that a fire occurred in the battery.

[0105] Therefore, the battery state diagnosis device 1000 according to the embodiments and experimental examples of the present invention can enable safe use of the battery by counting the number of times of diagnosing the abnormal state of the battery and transmitting an alarm to the administrator when the number of times is equal to or more than a predefined threshold number of times, as in steps S5000 to S6000 in FIG. 3.

[0106] The battery state diagnosis device and method according to the embodiments and experimental examples of the present invention have been described above.

[0107] The battery state diagnosis device and method according to the embodiments and experimental examples of the present invention can enable safe use of the battery by monitoring whether there is a specific cycle in which an abnormality occurs in the measured voltage value among the charging cycles of the battery, and diagnosing the abnormal state of the battery based on the charging time in the next cycle that progresses after the specific cycle.

[0108] The operations of the method according to the embodiments and experimental examples of the present invention can be embodied as a computer-readable program or code on a computer-readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Also, the computer-readable recording medium can be distributed to a computer system connected by a network, and a computer-readable program or code can be stored and executed in a distributed manner.

[0109] In addition, the computer-readable recording medium can include a hardware device specially configured to store and execute program instructions, such as a read-only memory (ROM), a random access memory (RAM), a flash memory, etc. The program instructions can include not only machine language code generated by a compiler but also high-level language code that can be executed by a computer using an interpreter or the like.

[0110] Some aspects of the present invention have been described in the context of an apparatus, which can also represent a corresponding method, where a block or apparatus corresponds to a method step or a feature of a method step. Similarly, aspects described in the context of a method can be represented by corresponding blocks or items or features of a corresponding apparatus. Some or all of the method steps can be performed by (or using) a hardware device such as a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, one or more of the most important method steps can be performed by such a device.

[0111] As described above with reference to the preferred embodiments of the present invention, those skilled in the art will understand that the present invention can be variously modified and changed without departing from the spirit and scope of the present invention described in the following claims.

Description of Reference Signs

[0112] 1000: Battery state diagnostic device 100: Memory 200: Processor 300: Transceiver 400: Input interface device 500: Output interface device 600: Storage device 700: Bus

Claims

1. A memory; and A processor for executing at least one instruction in the memory; including The at least one instruction is An instruction for monitoring whether there is a specific cycle in which an abnormality occurs in a voltage measurement value during a charging cycle of the battery, An instruction for checking the charging time of the battery in the next cycle proceeding after the specific cycle, and An instruction for diagnosing an abnormal state of the battery based on the charging time of the battery in the next cycle, a battery state diagnosis device.

2. The charging time is A first charging time that is the time for charging the battery in a constant current charging method, and A second charging time that is the time for charging the battery in a constant voltage charging method, the battery state diagnosis device according to claim 1.

3. The instruction for diagnosing the abnormal state of the battery is An instruction for diagnosing the abnormal state of the battery by comparing the charging time in the specific cycle with the charging time in the next cycle, the battery state diagnosis device according to claim 1.

4. The instruction for diagnosing the abnormal state of the battery is Whether the constant current charging time in the next cycle increases by a predefined first threshold value or more with respect to the specific cycle, or If the constant voltage charging time in the next cycle decreases by a predefined second threshold value or less with respect to the specific cycle, an instruction for determining that an abnormality has occurred in the battery, the battery state diagnosis device according to claim 3.

5. The instruction for diagnosing the abnormal state of the battery is The constant current charging time in the next cycle increases by a predefined first threshold value or more with respect to the specific cycle, If the constant voltage charging time in the next cycle decreases by a predefined second threshold value or less with respect to the specific cycle, an instruction for diagnosing that an abnormality has occurred in the battery, the battery state diagnosis device according to claim 3.

6. The monitoring instruction is An instruction for obtaining a plurality of OCV measurement values measured for each charging cycle, An instruction for monitoring whether there is at least one of the plurality of OCV measurement values that has a change amount equal to or greater than a predefined threshold value with respect to the OCV measurement value in the immediately preceding cycle, and An instruction for determining the cycle in which at least one of the OCV measurement values is measured as the specific cycle, the battery state diagnosis device according to claim 1.

7. The abnormal state of the battery is Including the state of risk of ignition of the battery or the state of occurrence of venting of the battery, the battery state diagnosis device according to claim 1.

8. An instruction for counting the number of times of diagnosing an abnormal state of the battery, and The battery state diagnosis device according to claim 1, further comprising an instruction for outputting an alarm when the counted number of times of diagnosing the abnormal state is equal to or greater than a predefined threshold value.

9. A state diagnosis method by a battery state diagnosis device, comprising: Monitoring whether there is a specific cycle in which an abnormality occurs in a voltage measurement value among charging cycles of the battery; Checking the charging time of the battery in the next cycle that proceeds after the specific cycle; and A battery state diagnosis method including a step of diagnosing an abnormal state of the battery based on the charging time of the battery in the next cycle.

10. The charging time is A first charging time which is the time for charging the battery in a constant current charging method, and The battery state diagnosis method according to claim 9, including a second charging time which is the time for charging the battery in a constant voltage charging method.

11. The step of diagnosing an abnormal state of the battery includes The battery state diagnosis method according to claim 9, including a step of comparing the charging time in the specific cycle with the charging time in the next cycle to diagnose an abnormal state of the battery.

12. The step of diagnosing an abnormal state of the battery includes Whether the constant current charging time in the next cycle increases by a predefined first threshold value or more with respect to the specific cycle, or The battery state diagnosis method according to claim 11, including a step of determining that an abnormality has occurred in the battery if the constant voltage charging time in the next cycle decreases by a predefined second threshold value or less with respect to the specific cycle.

13. The step of diagnosing an abnormal state of the battery includes The constant current charging time in the next cycle increases by a predefined first threshold value or more with respect to the specific cycle, The battery state diagnosis method according to claim 11, including a step of diagnosing that an abnormality has occurred in the battery if the constant voltage charging time in the next cycle decreases by a predefined second threshold value or less with respect to the specific cycle.

14. The monitoring step includes Obtaining a plurality of OCV measurement values measured for each charging cycle; Monitoring whether there is at least one of the OCV measurement values having a change amount equal to or greater than a predefined threshold value with respect to the OCV measurement value in the immediately previous cycle among the plurality of OCV measurement values; and The method for diagnosing the state of a battery according to claim 9, comprising the step of determining the corresponding cycle in which at least one of the OCV measurement values is measured as the specific cycle.

15. The abnormal state of the battery is the method for diagnosing the state of a battery according to claim 9, including the state of fire hazard of the battery or the state of venting occurrence of the battery.

16. the step of counting the number of times of diagnosing the abnormal state of the battery; and the method for diagnosing the state of a battery according to claim 9, further including the step of outputting an alarm when the counted number of times of diagnosing the abnormal state is equal to or greater than a predefined threshold value.

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