A method for testing the surface roughness of cylindrical batteries using surface gloss testing, the equipment for performing this method, and the storage medium for recording the program to execute this method.

Abstract

A method for testing the surface roughness of cylindrical batteries using surface gloss consists of two steps: firstly, using a testing device, obtaining an image of the cylindrical battery with applied illumination; and secondly, using a surface roughness testing device, obtaining the surface roughness of the area corresponding to the electrodes of the cylindrical battery using this image. A device for testing the surface roughness of cylindrical batteries using surface gloss is also proposed.

Description

A method for inspecting the surface roughness of a cylindrical battery through surface brightness, a device for performing the same, and a storage medium on which a program for performing the same is recorded.

[0001] This document relates to a method for inspecting the surface roughness of a cylindrical battery through surface brightness, an apparatus for performing the same, and a storage medium on which a program for performing the same is recorded.

[0002] Currently commercialized rechargeable batteries include nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium-ion batteries. Among these, lithium-ion batteries are gaining attention for their advantages over nickel-based batteries, such as the almost complete absence of the memory effect, allowing for free charging and discharging, a very low self-discharge rate, and high energy density.

[0003] Recently, secondary batteries are being widely used for propulsion or energy storage in vehicles such as electric motorcycles and electric vehicles, as well as in medium-to-large devices such as Energy Storage Systems (ESS). As a result, interest in batteries is increasing, and research and development related to batteries is becoming more active. Furthermore, in the case of batteries used in vehicles, commercialization and research on interchangeable battery packs are also being actively conducted.

[0004] Lithium secondary batteries primarily utilize lithium-based oxides and carbon materials as the positive and negative active materials, respectively. Furthermore, a lithium secondary battery comprises an electrode assembly in which a positive plate and a negative plate, each coated with the positive and negative active materials respectively, are arranged with a separator in between, and an outer casing (i.e., a battery case) that seals and encloses the electrode assembly along with the electrolyte. Depending on the shape of the outer casing, lithium secondary batteries can be classified into can-type secondary batteries, in which the electrode assembly is housed in a metal can, and pouch-type secondary batteries, in which the electrode assembly is housed in a pouch made of an aluminum laminate sheet. Additionally, can-type secondary batteries can be further classified into prismatic and cylindrical secondary batteries based on their shape.

[0005] A battery module or battery pack can be formed by housing multiple secondary batteries together inside a module case (module housing) or a pack case (pack housing) while electrically connected to each other. In this case, each secondary battery included in the battery module or battery pack may be referred to as a battery cell.

[0006] In particular, welding quality control is crucial during the welding process between the positive current collector of a cylindrical battery and the positive terminal of a can, as differences in weldability arise depending on the quality of the two materials to be welded. In the case of rivet-type positive terminals on cans, major factors affecting the welding of the positive current collector and the positive terminal include surface roughness, flatness, and hardness. Regarding surface roughness, one of these major factors, conventional surface roughness inspection methods consist of two types: contact and non-contact. Contact surface roughness inspection has the limitation that 100% inspection is practically impossible. Non-contact surface roughness inspection allows for 100% inspection but suffers from the problem of lower precision.

[0007] According to one embodiment of the present document, a method for inspecting the surface roughness of a cylindrical battery using surface brightness, an apparatus for performing the same, and a storage medium having a program for performing the same may be provided.

[0008] The problems to be solved in this disclosure are not limited to those mentioned above and can be extended in various ways without departing from the spirit and scope of this disclosure.

[0009] A method for inspecting the surface roughness of a cylindrical battery through surface brightness according to one embodiment of the present document comprises: a step of acquiring an inspection image of a cylindrical battery irradiated with light; and a step of acquiring the surface roughness of an area corresponding to a terminal of the cylindrical battery using the inspection image.

[0010] The above surface roughness acquisition step may be performed by acquiring the surface roughness of the area where the positive terminal of the cylindrical battery is welded.

[0011] The above-mentioned surface roughness acquisition step may be performed by measuring the surface brightness of the area where the positive terminal is welded, and acquiring the surface roughness of the cylindrical battery based on the measured surface brightness.

[0012] The above-mentioned surface roughness acquisition step may be performed by acquiring the surface roughness of the cylindrical battery based on the measured surface brightness using a preset relationship between surface brightness and surface roughness.

[0013] The method may further include the step of determining whether the cylindrical battery is defective based on the surface roughness of the cylindrical battery.

[0014] The above defect determination step may be performed by determining that the cylindrical battery is defective if the surface roughness of the cylindrical battery is greater than or equal to a preset roughness reference value.

[0015] The above inspection image acquisition step may be performed by acquiring the inspection image of the cylindrical battery through an in-line inspection device used to measure floating foreign matter and dimensions of the cylindrical battery.

[0016] The above inspection image acquisition step and the above surface roughness acquisition step can be performed by the above in-line inspection machine.

[0017]

[0018] A computer-readable storage medium according to one embodiment of the present document records a program for executing on a computer any one of the surface roughness inspection methods of a cylindrical battery through surface brightness described above.

[0019]

[0020] A surface roughness inspection device for a cylindrical battery through surface brightness according to one embodiment of the present document comprises: a memory storing one or more programs for inspecting the surface roughness of a cylindrical battery; and one or more processors performing an operation for inspecting the surface roughness of the cylindrical battery according to the one or more programs stored in the memory; wherein the processor acquires an inspection image of the cylindrical battery irradiated with light and acquires the surface roughness of an area corresponding to a terminal of the cylindrical battery using the inspection image.

[0021] The above processor can obtain the surface roughness of the area where the positive terminal of the cylindrical battery is welded.

[0022] The above processor can measure the surface brightness of the area where the positive terminal is welded and obtain the surface roughness of the cylindrical battery based on the measured surface brightness.

[0023] The above processor can obtain the surface roughness of the cylindrical battery based on the measured surface brightness by using a preset relationship between surface brightness and surface roughness.

[0024] The above processor can determine whether the cylindrical battery is defective based on the surface roughness of the cylindrical battery.

[0025] The processor can determine that the cylindrical battery is defective if the surface roughness of the cylindrical battery is greater than or equal to a preset roughness reference value.

[0026] The above processor can acquire the inspection image of the cylindrical battery through an in-line inspection device used to measure floating foreign matter and dimensions of the cylindrical battery.

[0027] The above-mentioned in-line inspection device is configured as an integral unit, so that the inspection image acquisition operation and the surface roughness acquisition operation can be performed by the in-line inspection device.

[0028] According to one embodiment of the present document, by inspecting the surface roughness of a cylindrical battery using surface brightness, the welding quality of the positive current collector plate of the cylindrical battery and the positive terminal of the can can be ensured, and component management through full inspection is possible.

[0029] In addition, according to one embodiment of the present document, it is possible to reduce losses by preventing semi-finished product defects and to reduce costs due to welding defects.

[0030] The effects according to the various embodiments of this document are not limited to those described above, and it is obvious to those skilled in the art that various effects are inherent in this disclosure.

[0031] FIG. 1 is a block diagram illustrating a surface roughness inspection device for a cylindrical battery through surface brightness according to one embodiment of the present document.

[0032] FIG. 2 is a drawing for explaining an example of an in-line inspection device illustrated in FIG. 1.

[0033] FIG. 3 is a block diagram illustrating the configuration of the surface roughness inspection device shown in FIG. 1.

[0034] FIG. 4 is a flowchart illustrating a method for inspecting the surface roughness of a cylindrical battery through surface brightness according to one embodiment of the present document.

[0035] FIG. 5 is a drawing for explaining an example of an area where the positive terminal of a cylindrical battery is welded in an inspection image according to one embodiment of the present document.

[0036] FIG. 6 is a diagram illustrating the relationship between surface brightness and surface roughness according to one embodiment of the present document, showing the surface roughness of each set of cylindrical batteries.

[0037] FIG. 7 is a diagram illustrating the relationship between surface brightness and surface roughness according to one embodiment of the present document, showing the surface brightness of each set of cylindrical batteries.

[0038] FIG. 8 is a diagram illustrating the relationship between surface brightness and surface roughness according to one embodiment of the present document, showing a 1:1 matching scatter plot between surface roughness and surface brightness.

[0039] Hereinafter, embodiments of this document will be described in detail with reference to the attached drawings. The advantages and features of the embodiments of this document, and the methods for achieving them, will become clear by referring to the details described below in conjunction with the attached drawings. However, the embodiments of this document are not limited to those disclosed below but can be implemented in various different forms, and the embodiments of this document are defined only by the scope of the claims.

[0040] Throughout the specification, the same reference numerals refer to the same components. Unless otherwise defined, all terms used in this specification (including technical and scientific terms) may be used in a meaning commonly understood by those skilled in the art to which the embodiments of this document pertain. Additionally, terms defined in commonly used dictionaries are not to be interpreted ideally or excessively unless explicitly and specifically defined otherwise.

[0041] In this specification, terms such as "first," "second," etc. are used to distinguish one component from another, and the scope of rights shall not be limited by these terms. For example, the first component may be named the second component, and similarly, the second component may be named the first component.

[0042] In this specification, identification symbols (e.g., a, b, c, etc.) for each step are used for convenience of explanation and do not indicate the order of the steps; the steps may occur differently from the specified order unless the context clearly indicates a specific order. That is, the steps may occur in the same order as specified, may be performed substantially simultaneously, or may be performed in the reverse order.

[0043] In this specification, expressions such as “have,” “may have,” “include,” or “may include” refer to the existence of the relevant feature (e.g., a numerical value, function, operation, or component, etc.) and do not exclude the existence of additional features.

[0044]

[0045] Hereinafter, with reference to the attached drawings, a method for inspecting the surface roughness of a cylindrical battery through surface brightness according to one embodiment of the present document, an apparatus for performing the same, and a storage medium having a program for executing the same are described in detail.

[0046]

[0047] First, with reference to FIG. 1, a surface roughness inspection device for a cylindrical battery through surface brightness according to one embodiment of the present document will be described.

[0048] FIG. 1 is a block diagram for explaining a surface roughness inspection device for a cylindrical battery through surface brightness according to one embodiment of the present document, and FIG. 2 is a drawing for explaining an example of an in-line inspection device shown in FIG. 1.

[0049] Referring to FIG. 1, a surface roughness inspection device for a cylindrical battery (hereinafter referred to as the 'surface roughness inspection device') (100) according to one embodiment of the present document can inspect the surface roughness of a cylindrical battery (200) using surface brightness.

[0050] At this time, the surface roughness inspection device (100) can obtain the surface brightness of the cylindrical battery (200) based on an image obtained through an in-line inspection device (300), and inspect the surface roughness of the cylindrical battery (200) based on the obtained surface brightness.

[0051] Here, the in-line inspector (300) refers to a device used to measure floating foreign matter and dimensions of a cylindrical battery (200). That is, referring to FIG. 2, the in-line inspector (300) can illuminate the "CAN" which is the cylindrical battery (200). Then, the in-line inspector (300) can obtain an inspection image by photographing the "CAN" which is the cylindrical battery (200) while it is illuminated. Then, the in-line inspector (300) can inspect whether floating foreign matter exists in the "CAN" which is the cylindrical battery (200) by using an image analysis algorithm or the like based on the acquired inspection image.

[0052]

[0053] Then, with reference to FIG. 3, the configuration of a surface roughness inspection device according to one embodiment of the present document will be described.

[0054] FIG. 3 is a block diagram illustrating the configuration of the surface roughness inspection device shown in FIG. 1.

[0055] Referring to FIG. 3, the surface roughness inspection device (100) may include one or more processors (110), a computer-readable storage medium (130), and a communication bus (150).

[0056] The processor (110) can control the surface roughness inspection device (100) to operate. For example, the processor (110) can execute one or more programs (131) stored in a computer-readable storage medium (130). One or more programs (131) may include one or more computer-executable instructions, and the computer-executable instructions may be configured to cause the surface roughness inspection device (100) to perform an operation to inspect the surface roughness of a cylindrical battery when executed by the processor (110).

[0057] A computer-readable storage medium (130) is configured to store computer-executable instructions or program code, program data and / or other suitable forms of information for inspecting the surface roughness of a cylindrical battery. A program (131) stored in the computer-readable storage medium (130) includes a set of instructions executable by a processor (110). In one embodiment, the computer-readable storage medium (130) may be memory (volatile memory such as random access memory, non-volatile memory, or a suitable combination thereof), one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, other forms of storage media that are accessed by the surface roughness inspection device (100) and capable of storing desired information, or a suitable combination thereof.

[0058] The communication bus (150) interconnects various other components of the surface roughness inspection device (100), including the processor (110) and the computer-readable storage medium (130).

[0059] The surface roughness inspection device (100) may also include one or more input / output interfaces (170) and one or more communication interfaces (190) that provide interfaces for one or more input / output devices. The input / output interface (170) and the communication interface (190) are connected to a communication bus (150). An input / output device (not shown) may be connected to other components of the surface roughness inspection device (100) through the input / output interface (170).

[0060]

[0061] Then, with reference to FIGS. 4 to 8, a method for inspecting the surface roughness of a cylindrical battery through surface brightness according to one embodiment of the present document will be described.

[0062] FIG. 4 is a flowchart for explaining a method for inspecting the surface roughness of a cylindrical battery through surface brightness according to one embodiment of the present document, FIG. 5 is a diagram for explaining an example of an area where the positive terminal of a cylindrical battery is welded in an inspection image according to one embodiment of the present document, FIG. 6 is a diagram for explaining a relationship between surface brightness and surface roughness according to one embodiment of the present document, showing the surface roughness of each set of cylindrical batteries, FIG. 7 is a diagram for explaining a relationship between surface brightness and surface roughness according to one embodiment of the present document, showing the surface brightness of each set of cylindrical batteries, FIG. 8 is a diagram for explaining a relationship between surface brightness and surface roughness according to one embodiment of the present document, showing a 1:1 matching scatter plot between surface roughness and surface brightness.

[0063] Referring to FIG. 4, the processor (110) of the surface roughness inspection device (100) can acquire an inspection image of a cylindrical battery (200) that has been illuminated (S110).

[0064] At this time, the processor (110) can obtain an inspection image of the cylindrical battery (200) through the in-line inspector (300).

[0065] Then, the processor (110) can obtain the surface roughness of the area corresponding to the terminal of the cylindrical battery (200) using the inspection image (S120).

[0066] That is, the processor (110) can obtain the surface roughness of the area where the positive terminal of the cylindrical battery (200) is welded.

[0067] To explain in more detail, the processor (110) can measure the surface brightness of the area where the positive terminal of the cylindrical battery (200) is welded. For example, in an inspection image as shown in FIG. 5, the surface brightness of the "surface brightness inspection area," which is the area where the positive terminal of the cylindrical battery (200) is welded, can be measured.

[0068] And, the processor (110) can obtain the surface roughness of the cylindrical battery (200) based on the measured surface brightness. At this time, the processor (110) can obtain the surface roughness of the cylindrical battery (200) based on the measured surface brightness by using a preset relationship between surface brightness and surface roughness.

[0069] Here, the relationship between surface brightness and surface roughness can be obtained and established based on the surface brightness and surface roughness measured in advance for a plurality of sets of cylindrical batteries (200). For example, the surface roughness can be measured for sets of cylindrical batteries (200) as shown in FIG. 6. Then, the surface brightness can be measured for sets of cylindrical batteries (200) as shown in FIG. 7. Then, a 1:1 matching scatter plot can be obtained based on the surface brightness and surface roughness measured for sets of cylindrical batteries (200) as shown in FIG. 8. Then, the relationship between surface brightness and surface roughness can be obtained based on the 1:1 matching scatter plot between the obtained surface roughness and surface brightness.

[0070] Afterwards, the processor (110) can determine whether the cylindrical battery (200) is defective based on the surface roughness of the cylindrical battery (200) (S130).

[0071] At this time, the processor (110) can determine that the cylindrical battery (200) is defective if the surface roughness of the cylindrical battery (200) is greater than or equal to a preset roughness reference value.

[0072]

[0073] To explain further, in order to manage the welding quality of the positive current collector plate of a cylindrical battery and the positive terminal of a can, a 100% inspection of surface roughness is required. For example, in the barrel process, which is one of the manufacturing processes for individual rivets, if process control is inadequate, the surface roughness of the rivet weld increases, and if it exceeds a certain roughness value, there is a problem of reduced weldability (reduction in tensile strength, deterioration of fracture mode, etc.). However, considering that a 100% inspection is practically impossible with conventional contact-type surface roughness inspection methods and that conventional non-contact-type surface roughness inspection methods have the problem of low precision, one embodiment of this document adopts surface brightness, which is a characteristic correlated with surface roughness, as a surrogate characteristic for surface roughness. By indirectly measuring surface roughness through surface brightness, a 100% inspection of surface roughness for weldability management can be performed more easily.

[0074]

[0075] Meanwhile, although it has been described that the surface roughness inspection device (100) is implemented as a physically separate device from the in-line inspection device (300) and that the surface roughness inspection device (100) performs an inspection image acquisition operation, a surface roughness acquisition operation, and a defect acquisition operation, this is merely an example, and according to the embodiment, the surface roughness inspection device (100) may be implemented as an integral part of the in-line inspection device (300). In this case, the inspection image acquisition operation, the surface roughness acquisition operation, and the defect acquisition operation may be performed by the in-line inspection device (300). That is, while the in-line inspection device (300) performs a floating foreign matter inspection operation, it may also perform an inspection image acquisition operation, a surface roughness acquisition operation, and a defect acquisition operation.

[0076]

[0077] The operation according to the embodiments of this document described above may be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer-readable storage medium. A computer-readable storage medium refers to any medium that participates in providing instructions to a processor for execution. A computer-readable storage medium may include program instructions, data files, data structures, or a combination thereof. Examples include magnetic media, optical storage media, memory, etc. Computer programs may be distributed over networked computer systems, and computer-readable code may be stored and executed in a distributed manner. Functional programs, code, and code segments for implementing the embodiments of this document will be readily deducible by programmers in the art to which the embodiments of this document belong.

[0078] The embodiments of this document are intended to illustrate technical concepts, and the scope of the technical concepts of the embodiments of this document is not limited by these embodiments. The scope of protection of the embodiments of this document shall be interpreted by the claims below, and all technical concepts within an equivalent scope shall be interpreted as being included within the scope of rights of the embodiments of this document.

[0079]

[0080] < Explanation of Symbols >

[0081] 100 : Surface roughness inspection device,

[0082] 110 : Processor,

[0083] 130 : Computer-readable storage media,

[0084] 131 : Program,

[0085] 150 : Communication bus,

[0086] 170 : Input / Output Interface,

[0087] 190 : Communication interface,

[0088] 200 : Cylindrical battery,

[0089] 300 : In-line inspector

Claims

1. A step of acquiring an inspection image of a cylindrical battery irradiated with light; and A step of obtaining the surface roughness of an area corresponding to the terminal of the cylindrical battery using the above inspection image; A method for inspecting the surface roughness of a cylindrical battery through surface brightness including 2. In Paragraph 1, The above surface roughness acquisition step is, The method comprises obtaining the surface roughness of the area where the positive terminal of the cylindrical battery is welded. Method for inspecting the surface roughness of a cylindrical battery through surface brightness.

3. In Paragraph 2, The above surface roughness acquisition step is, The method comprises measuring the surface brightness of the area where the positive terminal is welded, and obtaining the surface roughness of the cylindrical battery based on the measured surface brightness. Method for inspecting the surface roughness of a cylindrical battery through surface brightness.

4. In Paragraph 3, The above surface roughness acquisition step is, The method comprises obtaining the surface illuminance of the cylindrical battery based on the measured surface brightness using a preset relationship between surface brightness and surface illuminance. Method for inspecting the surface roughness of a cylindrical battery through surface brightness.

5. In Paragraph 1, A step of determining whether the cylindrical battery is defective based on the surface roughness of the cylindrical battery; A method for inspecting the surface roughness of a cylindrical battery through surface brightness, further including 6. In Paragraph 5, The above step of obtaining whether there is a defect is, If the surface roughness of the cylindrical battery is greater than or equal to a preset roughness reference value, the cylindrical battery is determined to be defective. Method for inspecting the surface roughness of a cylindrical battery through surface brightness.

7. In Paragraph 1, The above inspection image acquisition step is, The method comprises acquiring the inspection image of the cylindrical battery through an in-line inspection device used to measure floating foreign matter and dimensions of the cylindrical battery. Method for inspecting the surface roughness of a cylindrical battery through surface brightness.

8. In Paragraph 7, The above inspection image acquisition step and the above surface roughness acquisition step are, Performed by the above-mentioned in-line inspector, Method for inspecting the surface roughness of a cylindrical battery through surface brightness.

9. A computer-readable storage medium storing a program for executing on a computer a method for inspecting the surface roughness of a cylindrical battery through surface brightness as described in any one of claims 1 to 8.

10. Memory storing one or more programs for inspecting the surface roughness of a cylindrical battery; and One or more processors that perform an operation to inspect the surface roughness of the cylindrical battery according to one or more programs stored in the memory; Includes, The above processor is, Acquire an inspection image of the above-mentioned cylindrical battery illuminated by light, and Acquiring the surface roughness of an area corresponding to the terminals of the cylindrical battery using the above inspection image, Surface roughness inspection device for cylindrical batteries through surface brightness.

11. In Paragraph 10, The above processor is, Acquiring the surface roughness of the area where the positive terminal of the above-mentioned cylindrical battery is welded, Surface roughness inspection device for cylindrical batteries through surface brightness.

12. In Paragraph 11, The above processor is, Measuring the surface brightness of the area where the positive terminal is welded, and obtaining the surface roughness of the cylindrical battery based on the measured surface brightness, Surface roughness inspection device for cylindrical batteries through surface brightness.

13. In Paragraph 12, The above processor is, Using a preset relationship between surface brightness and surface illuminance, obtaining the surface illuminance of the cylindrical battery based on the measured surface brightness, Surface roughness inspection device for cylindrical batteries through surface brightness.

14. In Paragraph 10, The above processor is, Determining whether the cylindrical battery is defective based on the surface roughness of the cylindrical battery, Surface roughness inspection device for cylindrical batteries through surface brightness.

15. In Paragraph 14, The above processor is, If the surface roughness of the cylindrical battery is greater than or equal to a preset roughness reference value, the cylindrical battery is determined to be defective. Surface roughness inspection device for cylindrical batteries through surface brightness.

16. In Paragraph 10, The above processor is, Acquiring the inspection image of the cylindrical battery through an in-line inspection device used to measure floating foreign matter and dimensions of the cylindrical battery, Surface roughness inspection device for cylindrical batteries through surface brightness.

17. In Paragraph 16, A device configured as a single unit with the above-mentioned in-line inspection device, wherein the inspection image acquisition operation and the surface roughness acquisition operation are performed by the above-mentioned in-line inspection device. Surface roughness inspection device for cylindrical batteries through surface brightness.

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