Battery pack comprising monopole antenna, and battery pack inspection device for inspecting same

Abstract

The present invention relates to a battery pack, and a battery pack inspection device for inspecting same, the battery pack comprising: a plurality of cylindrical battery cells; a metal plate for electrically connecting the plurality of cylindrical battery cells; a monopole antenna attached to the plurality of cylindrical battery cells; and an antenna module connected to the monopole antenna.

Description

Battery pack including a monopole antenna and a battery pack inspection device for inspecting the same

[0001] This application claims the benefit of priority based on Korean Patent Application No. 2024-0180208 filed on December 6, 2024, and all contents disclosed in the document of said Korean patent application are incorporated herein as part of this specification.

[0002] The present invention relates to a battery pack including a monopole antenna and a battery pack inspection device for inspecting the same. Specifically, the invention relates to a battery pack including a monopole antenna capable of verifying the defect status of individual battery cells in a battery pack comprising a plurality of battery cells using a non-destructive inspection method, and a battery pack inspection device for inspecting the same.

[0003]

[0004] Rechargeable lithium secondary batteries are widely used as energy sources for wireless mobile devices or wearable devices worn on the body, as well as for electric vehicles and hybrid electric vehicles, which are presented as alternatives to conventional gasoline and diesel vehicles that cause air pollution.

[0005] Lithium-ion batteries with high energy density pose a risk of explosion due to overheating, and if ignition occurs, it is difficult to suppress until the entire battery is consumed.

[0006] Meanwhile, depending on the need for high-voltage and high-output energy sources, battery modules and battery packs containing multiple battery cells can be assembled and used; however, it is necessary to check whether there are any defective battery cells among the multiple battery cells inside to prevent risks such as explosions in advance.

[0007] However, conventionally, it was difficult to identify defective battery cells without disassembling battery modules and battery packs, and it was difficult to determine whether individual battery cells were defective using methods that measure the voltage of battery modules or battery packs.

[0008] In addition, while a method of checking for defects by attaching wired sensors to individual battery cells can be used, there is a problem in that additional costs are required to form lines for such wired sensing.

[0009] Patent Document 1 discloses a battery management device comprising a communication unit that transmits a first signal to a battery cell, a switch that connects the communication unit to the battery cell, and a controller that controls the operation of the switch, receives a second signal corresponding to the first signal, and diagnoses the state of the battery cell based on the second signal.

[0010] Patent Document 1 diagnoses the state of a battery cell based on a second signal transmitted from a battery cell, wherein the communication unit is connected to the battery cells via a wired connection, and the second signal indicating the state of the battery cells is configured to be transmitted through a wired line.

[0011] Therefore, facilities are required to establish wired lines, and expenditure is necessary for this.

[0012] Patent document 2 discloses a battery module comprising a plurality of battery cells constituting the battery module, an RFID tag attached to the plurality of battery cells, and a printed circuit board equipped with a radio frequency receiver that receives a temperature signal sent from the RFID tag.

[0013] Patent Document 2 must be equipped with multiple radio frequency receivers to receive temperature signals sent from each of the multiple battery cells.

[0014] Therefore, there is a need for a technology that can easily and quickly identify defective cells among the multiple battery cells constituting a battery pack, while simplifying the equipment required for this purpose to prevent wasted space and costs.

[0015] (Prior Art Literature)

[0016] (Patent Document 1) Korean Published Patent Application No. 2024-0016134 (February 6, 2024)

[0017] (Patent Document 2) Korean Published Patent Application No. 2020-0022309 (March 3, 2020)

[0018]

[0019] The present invention aims to solve the above-mentioned problems by providing a battery pack including a monopole antenna capable of detecting defective battery cells by wirelessly checking the state changes of cylindrical battery cells embedded in the battery pack, and a battery pack inspection device for inspecting the same.

[0020]

[0021] A battery pack according to the present invention for achieving such an objective may include a plurality of cylindrical battery cells, a metal plate electrically connecting the plurality of cylindrical battery cells, a monopole antenna attached to the plurality of cylindrical battery cells, and an antenna module connected to the monopole antenna.

[0022] In the battery pack according to the present invention, a monopole antenna may be attached to each of the plurality of cylindrical battery cells.

[0023] In the battery pack according to the present invention, the monopole antenna can be welded to a metal plate that is coupled to the positive terminal of a cylindrical battery cell.

[0024] In the battery pack according to the present invention, the monopole antenna may be made of a metal piece including copper or nickel.

[0025] In the battery pack according to the present invention, the monopole antenna is a planar rectangle, and the length of the longer side of the rectangle may be smaller than the diameter of the cylindrical battery cell.

[0026] In the battery pack according to the present invention, the monopole antenna may have a short side length of 1 mm or more in the rectangle.

[0027] A battery pack inspection device for inspecting a battery pack according to the present invention may include a power supply device that supplies power to the antenna module, and a measuring device that measures the pattern of a monopole antenna attached to the battery pack.

[0028] In a battery pack inspection device for inspecting a battery pack according to the present invention, the measuring device is an electromagnetic anechoic chamber, and the battery pack is placed in the electromagnetic anechoic chamber, and the 3D pattern radiated from the monopole antenna can be analyzed.

[0029] In a battery pack inspection device for inspecting a battery pack according to the present invention, the measuring device is a spectrum analyzer, and the spectrum analyzer can be connected to the battery pack to analyze the pattern of the measured signal.

[0030] In a battery pack inspection device for inspecting a battery pack according to the present invention, the radio wave pattern radiated by the monopole antenna varies depending on the impedance of the cylindrical battery cell to which it is coupled, and the measuring device measures the radio wave pattern of the monopole antenna, and if the shape is different among the radio wave patterns radiated by a plurality of monopole antennas, it can be determined as a defective battery cell.

[0031]

[0032] The present invention can also be provided in a form that combines various means for solving the above problem.

[0033]

[0034] The present invention uses a non-destructive inspection method that does not disassemble the battery pack, wherein a monopole antenna is attached to all battery cells and defective battery cells can be identified by analyzing the radiation pattern of the monopole antenna.

[0035] In addition, since a battery cell equipped with a monopole antenna that sends an abnormal pattern among the signals sent from the monopole antennas attached to each battery cell can be determined as defective, the defect status of the battery cell can be easily and accurately verified.

[0036] In addition, since the radiation pattern of the monopole antenna can be analyzed wirelessly, there is no need to build wired sensing lines to detect signals sent by the battery cell, thereby saving the necessary costs.

[0037]

[0038] FIG. 1 is a schematic diagram showing the interior of a battery pack according to the present invention.

[0039] FIG. 2 is an exploded perspective view showing the relationship in which a monopole antenna and a metal plate are combined with the cylindrical battery cell of FIG. 1.

[0040] FIG. 3 is a diagram showing the configuration of a battery pack inspection device according to the present invention.

[0041]

[0042] Embodiments that enable a person skilled in the art to easily practice the present invention are described in detail below with reference to the attached drawings. In describing the operating principles of the embodiments of the present invention in detail, specific descriptions of related known functions or configurations are omitted if it is determined that such detailed descriptions may unnecessarily obscure the essence of the present invention.

[0043] The same reference numerals are used for parts having similar functions and operations throughout the drawings. Throughout the specification, when a part is described as being connected to another part, this includes not only cases where they are directly connected but also cases where they are indirectly connected with other elements in between. Furthermore, the inclusion of a certain component means that, unless specifically stated otherwise, it does not exclude other components but rather implies that additional components may be included.

[0044] Descriptions that specify components by limiting or adding them may be applied to all inventions unless specifically limited, and are not limited to descriptions of specific inventions.

[0045] Throughout the description of the invention and claims of this application, anything indicated in the singular includes cases where it is plural unless otherwise noted.

[0046] Throughout the description of the invention and the claims of the present invention, "or" includes "and" unless otherwise noted. Therefore, "comprising A or B" means all three of the above cases: including A, including B, or including both A and B.

[0047] The present invention is described in detail with reference to the drawings and embodiments.

[0048] FIG. 1 is a schematic diagram showing the interior of a battery pack according to the present invention.

[0049] Referring to FIG. 1, a battery pack according to the present invention comprises a plurality of cylindrical battery cells (100), a metal plate (120) electrically connecting the plurality of cylindrical battery cells (100), a monopole antenna (210) attached to the plurality of cylindrical battery cells (100), and an antenna module (220) connected to the monopole antenna (210).

[0050] FIG. 1 is illustrated to include four cylindrical battery cells (100), but the number of cylindrical battery cells is not limited thereto. However, the plurality of cylindrical battery cells (100) are individually coupled one-to-one with a single monopole antenna (210). Additionally, within a single battery pack, all monopole antennas are configured to have the same size and shape.

[0051] Each monopole antenna (210) emits a unique pattern according to the impedance of the attached cylindrical battery cell (100), and since all monopole antennas have the same size and shape, all normal battery cells emit the same pattern.

[0052] However, in the case of defective battery cells, the radiation pattern of the monopole antenna is observed in a distorted form due to changes in impedance. Such a distorted pattern can be considered an abnormal pattern.

[0053] In this way, by checking the radiation pattern of the monopole antenna, if an abnormal pattern is observed, the cylindrical battery cell to which the monopole antenna is attached can be determined to be defective.

[0054] FIG. 2 is an exploded perspective view showing the relationship in which a monopole antenna and a metal plate are combined with the cylindrical battery cell of FIG. 1.

[0055] Referring to FIG. 2 together with FIG. 1, a metal plate (120) may be attached to the top of a cylindrical battery cell (100) for electrical connection between the cylindrical battery cells (100).

[0056] As a method for joining the cylindrical battery cell (100) and the metal plate (120), welding using a welding device (400) can be used, for example, laser welding, resistance welding, or ultrasonic welding can be used.

[0057] The monopole antenna (210) can be coupled to the positive terminal of the cylindrical battery cell (100), and the monopole antenna (210) can be attached to the cylindrical battery cell (100) using such a welding process.

[0058] In detail, the monopole antenna (210) can be coupled to the central protrusion of the top cap (110) which functions as a positive terminal in the cylindrical battery cell (100), and can be welded with the monopole antenna (210) interposed between the top cap (110) and the metal plate (120) as shown in FIG. 2. Alternatively, unlike as shown in FIG. 2, the metal plate (120) can be placed on the top cap (110) and the monopole antenna (210) can be welded with the monopole antenna (210) placed on the metal plate (120).

[0059] The monopole antenna (210) can be made of a metal material with excellent electrical conductivity, for example, a piece of metal containing copper or nickel can be used.

[0060] When considering the shape of the radiation pattern of the monopole antenna (210), it is preferable that the monopole antenna (210) be formed in a rectangular shape rather than a square shape in a planar plane. Accordingly, the monopole antenna (210) is configured to include a long side and a short side in a planar plane, and the short side length can be configured to be 1 mm or more. If the short side length of the monopole antenna (210) is smaller than 1 mm, the size of the radiation pattern is small and not easy to observe.

[0061] The long side length of the monopole antenna (210) can be made smaller than the diameter of the cylindrical battery cell. Specifically, when at least a portion of the monopole antenna (210) is coupled to a top cap that functions as a positive terminal, the other portion must not come into contact with a clamping portion that functions as a negative terminal.

[0062] Accordingly, the long side length of the monopole antenna (210) can be determined by considering the diameter of the cylindrical battery cell and the width of the crimping portion. For example, the long side length of the monopole antenna (210) can be longer than the short side length, but smaller than the diameter of the central protrusion of the top cap.

[0063] Meanwhile, the thickness of the monopole antenna (210) can be selected within the range of 50 μm to 150 μm, taking into account weldability.

[0064] FIG. 3 is a diagram showing the configuration of a battery pack inspection device according to the present invention.

[0065] Referring to FIG. 3, the battery pack inspection device according to the present invention can check whether the battery cells included in the battery pack are defective using a non-destructive inspection method.

[0066] Specifically, the battery pack inspection device additionally includes a power supply unit (300) that supplies power to an antenna module (220) in addition to the battery pack, and a measuring device (500) that measures the pattern of a monopole antenna attached to the battery pack.

[0067] In the battery pack inspection device of the present invention, the antenna module (220) can transmit a first signal to monopole antennas (210), and the monopole antennas (210) that receive the first signal can radiate a second signal.

[0068] The second signal radiated from the monopole antennas (210) may vary depending on the strength of the first signal sent from the antenna module (220), and since the component cost is high for high frequencies, the first signal may be a low frequency of 700 MHz to 1 GHz. In detail, the monopole antenna is configured with a short side length of 1 mm or more, so an antenna module having a bandwidth of 717 MHz to 861 MHz may be used.

[0069] After grounding the cylindrical battery cell (100) located at the bottom among the cylindrical battery cells (100) of Fig. 3, when power is applied to the monopole antennas (210) and the cylindrical battery cells (100), current flows between the monopole antennas and the ground plane, and a second signal is radiated.

[0070] Subsequently, the ground plane is removed, and the difference in radiation patterns caused by the impedance of the normal cylindrical battery cell and the impedance of the abnormal cylindrical battery cell is analyzed.

[0071] The measuring device (500) can measure and analyze the radio wave pattern (230, 230') radiated from the entire plurality of monopole antennas (210) coupled to each individual battery cell.

[0072] The radio wave pattern radiated by the monopole antenna (210) varies depending on the impedance of the combined cylindrical battery cell (100), and the measuring device (500) measures the radio wave pattern (230, 230') of the monopole antenna (210), and if the shape is different among the radio wave patterns (230, 230') radiated from the plurality of monopole antennas (210), it is determined to be a defective battery cell.

[0073] In the case of defective cylindrical battery cells, as the resonance frequency changes with increasing impedance, radiation may not occur, or radiation patterns smaller than tens of times or asymmetrical radiation patterns may appear.

[0074] In the case of FIG. 3, the radio wave pattern (230') radiated from the monopole antenna (210') coupled to the cylindrical battery cell (100') among the four cylindrical battery cells (100, 100') appears as a skewed shape. On the other hand, the radio wave pattern (230) radiated from the monopole antenna (210) coupled to the other cylindrical battery cells (100) is generally symmetrical in shape, and it is measured that the three monopole antennas (210) radiate the same type of radio wave pattern. Therefore, the cylindrical battery cell (100) can be determined to be a normal battery cell, and the cylindrical battery cell (100') can be determined to be a defective battery cell.

[0075] In addition, since the radio wave pattern radiated by the monopole antennas is in the form of a wireless signal, the measuring device (500) is configured to receive the wireless signal.

[0076] For example, the measuring device (500) is an electromagnetic anechoic chamber, and the defective battery cell can be determined by placing the battery pack in the electromagnetic anechoic chamber and analyzing the 3D pattern radiated from the monopole antenna.

[0077] Alternatively, the measuring device (500) is a spectrum analyzer, and the spectrum analyzer is an instrument that decomposes the spectrum or frequency of a signal and displays its magnitude on a screen. The spectrum analyzer can be connected to the battery pack to analyze the pattern of the measured signal.

[0078] Accordingly, the present invention comprises a monopole antenna that radiates a wireless signal attached to each of all battery cells and an antenna module that sends a first signal to the monopole antenna, wherein the monopole antenna radiates a second signal corresponding to the first signal as a radio wave pattern, and since the impedance of the cylindrical battery cell affects the radio wave pattern, the monopole antenna coupled to the defective battery cell emits an abnormal radio wave pattern, thereby confirming that the cylindrical battery cell is defective.

[0079]

[0080] A person skilled in the art to which the present invention pertains would be able to perform various applications and modifications within the scope of the present invention based on the above content.

[0081] (Explanation of symbols)

[0082] 100, 100': Cylindrical battery cell

[0083] 110: Top Cap

[0084] 120: Metal plate

[0085] 210, 210': Monopole antenna

[0086] 220: Antenna module

[0087] 230, 230': Propagation pattern

[0088] 300: Power supply

[0089] 400: Welding device

[0090] 500: Measuring device

Claims

1. Multiple cylindrical battery cells; A metal plate that electrically connects the plurality of cylindrical battery cells above; A monopole antenna attached to the plurality of cylindrical battery cells above; and An antenna module connected to the above monopole antenna; A battery pack including 2. In Paragraph 1, A battery pack having a monopole antenna attached to each of the above plurality of cylindrical battery cells.

3. In Paragraph 2, The above monopole antenna is a battery pack that is welded to a metal plate that is coupled to the positive terminal of a cylindrical battery cell.

4. In Paragraph 1, The above monopole antenna is a battery pack made of a metal piece containing copper or nickel.

5. In Paragraph 1, The above monopole antenna is a planar rectangle, and the battery pack is formed such that the length of the longer side of the rectangle is smaller than the diameter of the cylindrical battery cell.

6. In Paragraph 5, The above monopole antenna is a battery pack in which the short side length of the above rectangle is 1 mm or more.

7. A battery pack inspection device for inspecting a battery pack according to any one of paragraphs 1 through 6, A power supply device that supplies power to the above antenna module; and A measuring device for measuring the pattern of a monopole antenna attached to the battery pack; A battery pack inspection device including 8. In Paragraph 7, The above measuring device is an electromagnetic anechoic chamber, and A battery pack inspection device that places the battery pack in the electromagnetic wave anechoic chamber and analyzes the 3D pattern radiated from the monopole antenna.

9. In Paragraph 7, The above measuring device is a spectrum analyzer, and A battery pack inspection device that analyzes the pattern of a measured signal by connecting the spectrum analyzer to the battery pack.

10. In Paragraph 7, The above monopole antenna has a different radio wave pattern depending on the impedance of the coupled cylindrical battery cell, and The above measuring device measures the propagation pattern of the monopole antenna, and A battery pack inspection device that determines a defective battery cell when the shape of the radio wave patterns radiated from multiple monopole antennas is different.

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