CN-122003614-A - Battery diagnosis apparatus and method of operating the same

Abstract

The battery diagnosis apparatus according to one embodiment of the present disclosure may include an acquisition unit that acquires Open Circuit Voltage (OCV) data of a plurality of battery cells, a deviation calculation unit that calculates an OCV variation value of the plurality of battery cells in a first period based on the OCV data and calculates an OCV deviation value with respect to an average value that represents a difference between the average OCV variation value of the plurality of battery cells and an OCV variation value of a target battery cell among the plurality of battery cells, a standard deviation calculation unit that calculates a first determination value that represents a standard deviation of the target battery cell with respect to the average value in a second period, and a diagnosis unit that diagnoses an abnormality of the target battery cell based on the first determination value of the target battery cell.

Inventors

• JIN YONGMIN

Assignees

• 株式会社LG新能源

Dates

Publication Date

20260508

Application Date

20240923

Priority Date

20231013

Claims (14)

1. 1. A battery diagnosis apparatus, the battery diagnosis apparatus comprising: an acquisition unit configured to acquire Open Circuit Voltage (OCV) data of a plurality of battery cells; A deviation calculation unit configured to calculate OCV variation values of the plurality of battery cells over a first period of time based on the OCV data, and calculate an OCV deviation value with respect to an average value, which is a difference value between the average OCV variation value of the plurality of battery cells and an OCV variation value of a target battery cell among the plurality of battery cells; A standard deviation calculation unit configured to calculate a first determination value representing a standard deviation of the target battery cell with respect to an OCV deviation value of an average value in a second period of time, and And a diagnosis unit configured to diagnose an abnormality of the target battery cell based on the first determination value of the target battery cell.
2. 2. The battery diagnosis device according to claim 1, wherein the diagnosis unit is further configured to diagnose the target battery cell as an abnormal battery cell when the first determination value is greater than or equal to a first threshold value.
3. 3. The battery diagnosis apparatus according to claim 1, further comprising an average value calculation unit configured to calculate a second determination value representing an average value of the first determination values of the plurality of battery cells, Wherein the diagnosis unit is further configured to diagnose abnormality of a high-level battery cell including the plurality of battery cells based on the second determination value.
4. 4. The battery diagnosis apparatus according to claim 3, wherein the diagnosis unit is further configured to diagnose the high-level battery cell as an abnormal battery cell when the second determination value is greater than or equal to a second threshold value.
5. 5. The battery diagnosis device according to claim 1, wherein the first period is a period between a point in time before charging is performed on a battery cell and a point in time after the charging is performed.
6. 6. The battery diagnosis device according to claim 1, wherein the acquisition unit is further configured to: acquiring time-series voltage data and time-series current data of the plurality of battery cells, and Based on the time-series voltage data and the time-series current data, the OCV data having a specified current value and a specified voltage range is acquired.
7. 7. The battery diagnosis apparatus according to claim 1, further comprising an abnormality processing unit configured to perform an abnormality processing function based on an abnormality diagnosis result of each of the plurality of battery cells, Wherein the exception handling function includes a notification function or a short circuit function.
8. 8. A battery diagnosis method, comprising the steps of: acquiring Open Circuit Voltage (OCV) data of a plurality of battery cells; Calculating OCV variation values of the plurality of battery cells over a first period of time based on the OCV data; Calculating an OCV deviation value with respect to an average value, the OCV deviation value with respect to the average value being a difference between an average OCV variation value of the plurality of battery cells and an OCV variation value of a target battery cell among the plurality of battery cells; calculating a first determination value representing a standard deviation of the OCV deviation value of the target battery cell with respect to the average value in a second period of time, and An abnormality of the target battery cell is diagnosed based on the first determined value of the target battery cell.
9. 9. The battery diagnosis method according to claim 8, wherein the step of diagnosing abnormality of the target battery unit includes the step of diagnosing the target battery unit as an abnormal battery unit when the first determination value is greater than or equal to a first threshold value.
10. 10. The battery diagnosis method according to claim 8, further comprising the steps of: calculating a second determination value representing an average value of the first determination values of the plurality of battery cells, and Diagnosing abnormality of a high-level battery cell including the plurality of battery cells based on the second determination value.
11. 11. The battery diagnosis method according to claim 10, wherein the step of diagnosing abnormality of the high-level battery unit includes the step of diagnosing the high-level battery unit as an abnormal battery unit when the second determination value is greater than or equal to a second threshold value.
12. 12. The battery diagnosis method according to claim 8, wherein the first period of time is a period of time between a point of time before charging is performed on a battery cell and a point of time after the charging is performed.
13. 13. The battery diagnosis method according to claim 8, wherein the step of acquiring OCV data of the plurality of battery cells includes the steps of: acquiring time-series voltage data and time-series current data of the plurality of battery cells, and Based on the time-series voltage data and the time-series current data, the OCV data having a specified current value and a specified voltage range is acquired.
14. 14. The battery diagnosis method according to claim 8, further comprising the step of performing an abnormality processing function based on an abnormality diagnosis result of each of the plurality of battery cells, Wherein the exception handling function includes a notification function or a short circuit function.

Description

Battery diagnosis apparatus and method of operating the same Technical Field Cross Reference to Related Applications The present application claims priority and benefit from korean patent application No. 10-2023-0137714 filed on the korean intellectual property office on day 10 and 13 of 2023, the entire contents of which are incorporated herein by reference. Technical Field Embodiments disclosed herein relate to a battery diagnosis apparatus and a method of operating the same. Background Recently, research and development of secondary batteries have been actively conducted. Herein, the secondary battery, which is a chargeable/dischargeable battery, may include all conventional nickel (Ni)/cadmium (Cd) batteries, ni/Metal Hydride (MH) batteries, etc., as well as recent lithium ion batteries. Among secondary batteries, lithium ion batteries have much higher energy density than conventional Ni/Cd batteries, ni/MH batteries, and the like. Further, lithium ion batteries can be manufactured to be small and light in weight, so that the lithium ion batteries have been used as power sources for mobile devices, and recently, their use ranges have been expanded to power sources for electric vehicles, thereby attracting attention as next-generation energy storage media. In addition, secondary batteries are generally used as battery packs including battery modules in which a plurality of battery cells are connected in series and/or parallel with each other. The secondary battery may be used as a battery chassis including a plurality of battery modules and a chassis frame accommodating the battery modules. The battery cells, battery modules, battery packs, or battery racks may be used in a variety of devices. For example, the battery may be used not only for mobile devices such as mobile phones, laptop computers, smartphones, etc., but also in the fields of electrically driven vehicles (electric vehicles (EVs), hybrid Electric Vehicles (HEVs), plug-in HEVs (PHEVs)), large-capacity Energy Storage Systems (ESS), etc. These batteries may be managed and controlled in terms of their status and operation by a Battery Management System (BMS). The battery management system may be included in one device together with the battery. The battery management system may also manage and control the battery in a state spaced apart from the device including the battery. For example, the battery management system may be implemented as a separate server device. In this case, the battery management system may collect battery data and vehicle data and the like from the vehicle and the like, and use the collected data to manage and control the battery. Disclosure of Invention Technical problem The likelihood of damage to devices (e.g., EV, ESS) including the battery may increase when a short circuit or another type of fault occurs inside the battery. Therefore, a scheme for reducing the possibility of damage to a device including a battery by detecting an abnormal state of the battery is required. Traditionally, battery cells have been diagnosed by a calculation scheme using all state of charge (SOC), current, capacity, and Open Circuit Voltage (OCV) information. According to such a diagnostic method, it may be difficult to perform diagnosis when specific information among the aforementioned information is missing because of the use of many factors. This may be a large problem in the battery management system implemented with the server device that must collect data from the vehicle, and may excessively increase memory usage. Therefore, there is a need to simplify the data required for battery diagnosis. According to the embodiments disclosed herein, a battery diagnosis apparatus and an operation method thereof, by which an abnormality of a battery can be diagnosed using only battery OCV data information, may be provided. The technical problems of the embodiments disclosed herein are not limited to the above-described technical problems, and other technical problems not mentioned will be clearly understood by those of ordinary skill in the art from the following description. Technical proposal The battery diagnosis apparatus according to the embodiments disclosed herein includes an acquisition unit configured to acquire Open Circuit Voltage (OCV) data of a plurality of battery cells, a deviation calculation unit configured to calculate an OCV variation value of the plurality of battery cells over a first period of time based on the OCV data and calculate an OCV variation value with respect to an average value, which is a difference between the average OCV variation value of the plurality of battery cells and an OCV variation value of a target battery cell among the plurality of battery cells, a standard deviation calculation unit configured to calculate a first determination value indicating a standard deviation of the target battery cell with respect to the average value in a second period of time, and a diagnosis unit configured to diagnose