PCB containing current lines around the boss hole

Abstract

The present invention provides a PCB having boss holes in the shape of holes for fixing the PCB substrate, and having an electrical pattern arranged along the inner surface of the boss holes. As a result, the present invention makes it possible to utilize conventional PCBs as they are and ensure the allowable current by increasing the energy density even in environments where physical and spatial constraints are increasingly imposed.

Description

Technical Field

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0160458 filed on November 20, 2023, and all the contents disclosed in the Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a PCB including current lines around a boss hole. Specifically, it relates to a PCB including a vertical metal plate for current lines around a boss hole (Boss hole) through which the PCB can be fixed to a device.

Background Art

[0003] Lithium secondary batteries measure and monitor the temperature, voltage, etc. of battery cells for safety. A PCB manufactured for such purposes is called a BMU (Battery Management Unit), and the electrode leads of battery cells are electrically connected to the PCB.

[0004] IT products such as smartphones and notebook computers are miniaturized and lightweight, but the battery modules or battery packs used therein are rather high-density and high-capacity. Due to the limitation of the space where components can be arranged, the BMU is also very dense. Nevertheless, in the case of IT products that are frequently moved, the BMU must necessarily have a boss hole (Boss Hole) for fixation.

[0005] Figure 1 is a schematic diagram showing a portion of the top surface of a conventional BMU 100, and Figure 2 is a perspective view showing a portion of the BMU configuration in a conventional battery pack. The x, y, and z coordinates shown in Figures 1 and 2 are based on the same reference points. Referring to Figure 2, the BMU 100 is positioned in the center of a battery cell 200 equipped with electrode leads 210, and the BMU 100 is connected to an external current line 140. The BMU 100 is provided with boss holes 120 for fixing to the battery pack. Referring to Figure 1, the left side of the BMU 100 is provided with numerous welds 110. These welds 110 are welded to the external current line 140 in Figure 2. The electrode leads of the battery cell, sensors, external output terminals, etc., are welded to these welds 110. The central part of Figure 1 is provided with boss holes 120 for fixing the BMU 100. Each weld 110 is connected to its respective current line 130 and electrically connected to various elements within the BMU. In Figure 1, the main current line 130, used for illustrative purposes, is omitted, while the rest are omitted.

[0006] By providing the boss hole 120 in the horizontal plane (xy plane) of the BMU, there is insufficient space to arrange the current lines horizontally. Since the boss hole 120 is simply a hole for fixing the BMU 100, the current lines must be arranged in the remaining area after removing it. As the width of the current line 130 becomes narrower, the maximum allowable current also decreases. Although the maximum allowable current should increase as the energy density of the battery module or battery pack increases, the problem arises that the space for arranging the current lines actually decreases due to the compact and densely packed BMUs.

[0007] Even though BMUs are multilayer PCBs, the problem of gradually decreasing current capacity persists. Due to issues such as heat generation, it's impossible to place high-capacity current lines in the inner layers of the PCB. Nevertheless, additional means must be provided to ensure sufficient current capacity through increased energy density.

[0008] Patent Document 1 relates to a technique for ensuring electrical connection, i.e., conductivity, between a conductor pattern formed on a printed circuit board and a case via mounting screws for fixing the printed circuit board and the case, and for ensuring grounding, i.e., a GND connection, to the case.

[0009] Patent Document 2 provides a printed circuit board with a thinned frame ground portion, comprising a frame ground portion 11 with conductor patterns 13a and 13b formed around fixing mounting holes 12, and a plurality of through-holes 14 provided around the mounting holes 12 in the frame ground portion 11, wherein solder paste 15 is applied to the through-holes 14 in the solder paste printing step of the component mounting process, the solder paste 15 is melted in the reflow step, and a portion of the molten solder paste 15 is introduced into the through-holes 14 to adhere to the through-holes 14 and the conductor patterns 13a and 13b around them, thereby forming a solder coating.

[0010] Patent Document 3 describes a method for preventing screw holes from being blocked by solder during the soldering process without requiring special treatment. It involves forming screw holes 16 in the circuit board 10 through which screws 50 pass. Copper foil is not formed on the inner wall of the screw holes 16. A first conductive portion 20 is formed around the screw holes 16 on the first main surface 12 of the circuit board 10. The head 52 of the screw 50 contacts the first conductive portion and is electrically connected when the circuit board 10 is fixed to the housing. The ground layer 28 of the circuit board 10 and the first conductive portion 20 are connected by through-holes 18. A second conductive portion is further present on the second main surface of the circuit board 10 and is electrically connected by through-holes 18. When the screw 50 is screwed into the screw hole 62 of the fixing column 60 of the electronic equipment housing, the screw 50 and the second conductive portion 22 are electrically connected to the housing, and thus the ground layer 28 is electrically connected to the housing.

[0011] Patent documents 1 to 3 describe a PCB configuration that includes conductive material on the inner surface or above and below the grounding hole for grounding purposes. While this is intended to electrically connect the PCB to the case, it does not provide a suitable solution to the problem of needing to secure a current line, as in the present invention.

[0012] Patent Document 4 describes a technique for simply fixing a circular hole and a metal tube inserted therein electrically and physically using a riveting method, but it does not provide a solution to the problems of the present invention.

[0013] Thus, no technology has been presented that allows for the continued use of conventional PCBs while ensuring sufficient current capacity through increased energy density, even in environments where physical and spatial constraints gradually increase. In particular, the problem of BMUs used in IT products such as smartphones and notebook PCs, where energy density increases as they become smaller and lighter, must be solved. [Prior art documents] [Patent Documents]

[0014] [Patent Document 1] Japanese Patent Publication No. 2014-090018

[0015] [Patent Document 2] Japanese Patent Publication No. 2009-212124

[0016] [Patent Document 3] Japanese Patent Publication No. 1996-236878 Specification

[0017] [Patent Document 4] Korean Patent Publication No. 2179678 [Overview of the project] [Problems that the invention aims to solve]

[0018] Thus, an object of the present invention is to provide a technology that can utilize a conventional PCB as it is and ensure an allowable current by increasing the energy density even in an environment where physical / space constraints gradually occur. In particular, an object is to provide a technology that can ensure an allowable current in a BMU used in IT products where the energy density increases as they are miniaturized / lightweighted, such as smartphones and notebook PCs.

Means for Solving the Problems

[0019] In order to achieve the above object, there is provided a PCB having a boss hole in the form of a hole for fixing a PCB substrate, the PCB comprising an electrical pattern disposed along the inner surface of the boss hole. The hole form of the boss hole is usually cylindrical, but is not limited thereto. If necessary, the hole form of the boss hole can be polygonal.

[0020] The electrical pattern can be composed of metal. The electrical pattern can be anything as long as it is a conductive substance. A paste form having conductive properties can also be used, but it is preferable to use copper metal usually used for PCBs.

[0021] The electrical pattern can be composed of copper used for the circuit pattern of the PCB in the form of a thin strip-shaped metal plate. The strip form is disposed along the side surface of the boss hole. The width of the strip form may be smaller than the depth of the boss hole. That is, the circuit pattern of a normal PCB is disposed horizontally on the PCB substrate. Here, it can also be laminated in multiple layers. On the other hand, the electrical pattern according to the present invention is characterized in that it is disposed vertically.

[0022] On the other hand, the electrical pattern can be composed of multiple layers. By configuring the electrical pattern disposed along the inner surface of the boss hole in multiple layers, it is possible to further arrange the electrical pattern that becomes insufficient due to the boss hole.

[0023] It can be provided with a connecting portion located on the upper surface of the PCB and electrically connected to the electrical pattern. Since the electrical pattern is arranged vertically, different from the existing circuit patterns arranged on the PCB, a connecting portion capable of connecting it to the existing circuit patterns is required. Two connecting portions can be provided at the start and end of the electrical pattern. The connecting portion is arranged horizontally and is electrically continuously connected to the electrical pattern.

[0024] It is provided with a vertical gap portion which is a vertical cutting gap further extending from the boss hole, and the electrical pattern can extend to the vertical gap portion. Two vertical gap portions are provided symmetrically with respect to the boss hole, and the connecting portion can be electrically connected to the electrical pattern extending to the vertical gap portion. On the other hand, the electrical pattern can be physically fixed by the vertical gap portion.

[0025] Two electrical patterns can be provided on the left and right along the inner surface of the boss hole. The portion of the electrical pattern exposed to the outside can be coated with an insulating substance.

[0026] The electrical pattern can be adhered to the inner surface of the boss hole.

[0027] A ring-shaped protection portion can be provided outside the electrical pattern. The protection portion is an insulator and can electrically isolate the electrical pattern from bolts fixed through the boss hole and the like.

[0028] The PCB can be used as a BMU (Battery Management Unit) used in a battery module.

[0029] The present invention also provides a battery module including the PCB.

[0030] The present invention can also be provided as a configuration in which the problems to be solved are arbitrarily combined. [Effects of the Invention]

[0031] This invention provides a PCB having boss holes in the shape of holes for fixing the PCB substrate, and further providing an electrical pattern along the inner surface of the boss holes. This allows the invention to utilize conventional PCBs as they are and provide a technology that ensures allowable current through increased energy density, even in environments where physical and spatial constraints are increasingly imposed. This technology can also be used in BMUs (Battery Units) used in IT products such as smartphones and notebook PCs, where energy density increases as they become smaller and lighter, thus ensuring allowable current.

[0032] Existing boss holes are non-conductive, but the present invention adds an electrical pattern to them. Unlike existing circuit patterns, it is arranged vertically, so it can provide additional electrical patterns that are lacking. The electrical pattern can consist of multiple layers. By arranging the electrical pattern along the inner surface of the boss hole in multiple layers, it is possible to provide additional electrical patterns that are lacking due to the boss hole.

[0033] The electrical pattern can consist of multiple layers, or two patterns can be provided on the left and right sides along the inner surface of the boss hole. In this case, the multiple layers or the patterns provided on the left and right sides can be used as separate transmission means. [Brief explanation of the drawing]

[0034] [Figure 1] This is a schematic diagram showing a portion of the top surface of a conventional BMU.

[0035] [Figure 2] This is a perspective view showing part of the BMU configuration in a conventional battery pack.

[0036] [Figure 3]This is a perspective view of a boss hole according to the first embodiment of the present invention.

[0037] [Figure 4] This is a perspective view of a boss hole according to a second embodiment of the present invention. [Modes for carrying out the invention]

[0038] Hereinafter, with reference to the attached drawings, embodiments that allow a person with ordinary skill in the art to carry out the present invention will be described in detail. However, in describing in detail the operating principles of preferred embodiments of the present invention, if it is determined that a specific description of a related known function or configuration may unnecessarily obscure the gist of the present invention, such detailed description will be omitted.

[0039] Furthermore, the same reference numerals shall be used throughout the drawings for parts that have similar functions and operations. Throughout the specification, when it is said that one part is connected to another part, this includes not only direct connections but also indirect connections through other elements in between. Also, when it is said that a component is included, unless otherwise stated, it does not mean that other components are excluded, but rather that other components may be included.

[0040] The PCB according to the present invention will be described below with reference to the attached drawings. The PCB according to the present invention differs from conventional PCBs only in the boss holes and the electrical patterns arranged therein. Figure 3 is a perspective view of a boss hole according to the first embodiment of the present invention. Figure 3 omits other components of the PCB and shows only the boss holes and the electrical patterns arranged therein. Figure 3a is a magnified view of only the boss hole portion, Figure 3b shows only the electrical patterns and connecting portions, and Figure 3c shows other modified examples of the electrical patterns.

[0041] Referring to Figure 3, the PCB, specifically the BMU 500, is provided with boss holes 520 in the shape of holes for fixing the PCB, and electrical patterns 550 arranged along the inner surface of the boss holes 520. The boss holes 520 have a cylindrical shape. The electrical patterns 550 are made of copper metal used in the PCB. The electrical patterns 550 are made of copper metal in the shape of a strip. The strip is arranged along the side surface of the boss hole. The width W of the strip may be the same as or less than the depth D of the boss hole 520. While circuit patterns on a normal PCB are arranged horizontally on the PCB substrate, the electrical patterns 550 according to the present invention are characterized in that they are arranged vertically.

[0042] The BMU 500 may be equipped with a coupling section 560 located on its upper surface and electrically connected to the electrical pattern 550. Unlike existing circuit patterns placed in the BMU, the electrical pattern 550 is arranged vertically. For this reason, a coupling section 560 is required to connect it to the existing circuit patterns. Two coupling sections 560 are provided, one at the beginning and one at the end of the electrical pattern 550. The coupling sections 560 are arranged horizontally and are electrically continuous with the electrical pattern 550.

[0043] The connecting portion 560 can be continuously connected to the circuit pattern in a conventional BMU without being configured in a separate form. However, since the electrical pattern 550 according to the present invention is in a vertical form, a separate connecting portion 560 is provided as shown in Figure 3, and the connecting portion 560 can be connected to the circuit pattern of a conventional BMU.

[0044] A vertical gap section 525, which is a vertical incision gap extending from the boss hole 520, is provided, and the electrical pattern 550 extends to the vertical gap section 525. Two vertical gap sections 525 are provided symmetrically on the boss hole 520, and the connecting section 560 is electrically connected to the electrical pattern 550 that extends to the vertical gap section 525. The electrical pattern 550 is inserted and fixed by the vertical gap section 525. Figure 3c shows an example in which one of the connecting sections 560 is deformed. The connecting section 560A in Figure 3c is in a form that can be immediately fixed to the upper surface of the BMU 500 even without the vertical gap section 525. The connecting section 560A can be placed on both ends of the electrical pattern 550. In this case, the vertical gap section 525 is not separately required.

[0045] Although Figure 3 shows a single electrical pattern 550, this can be modified to consist of multiple layers. By composing the electrical pattern arranged along the inner surface of the boss hole 520 into multiple layers, additional electrical patterns that would otherwise be lacking due to the boss hole can be provided. In this case, multiple layers of electrical patterns are also inserted into the vertical gap. However, if the electrical patterns arranged as multiple layers operate as independent circuits, multiple connecting parts 560 must also be provided. Figure 3a shows only one connecting part 560 at the beginning and end, but multiple connecting parts 560 can be provided at each end. In this case, the vertical gap extends further, and the connecting parts 560 are electrically disconnected, but multiple connecting parts can be arranged adjacent to each other.

[0046] Figure 4 is a perspective view of a boss hole according to a second embodiment of the present invention. The second embodiment is the same as the first embodiment except that two electrical patterns are provided on the left and right sides along the inner surface of the boss hole, so the explanation of the overlapping parts will be omitted.

[0047] Referring to Figure 4, the second embodiment has two electrical patterns 550, one on each side along the inner surface of the boss hole 520. Consequently, the number of connecting parts 560 has also increased from two to four. The two electrical patterns 550 may consist of a single electrical connection, or an insulator may be provided between the two electrical patterns 550, forming two separate electrical connections.

[0048] Furthermore, the portion of the electrical pattern exposed to the outside is coated with an insulating material, and the electrical pattern can be bonded to the inner surface of the boss hole. In addition, a ring-shaped protective portion may be provided on the outside of the electrical pattern. The protective portion is an insulator and can electrically separate the electrical pattern from bolts and other fasteners fixed through the boss hole.

[0049] The present invention also provides a battery module including the aforementioned PCB.

[0050] Although specific parts of the present invention have been described in detail above, such specific techniques are merely preferred modes of implementation and do not limit the scope of the present invention. It will be obvious to those skilled in the art that various changes and modifications are possible within the scope of the present invention and its technical concept, and it goes without saying that such variations and modifications also fall within the scope of the appended claims. [Explanation of symbols]

[0051] 100, 500 BMU

[0052] 110 Welded section

[0053] 120, 520 Bosshole

[0054] 525 Vertical gap

[0055] 130 Current Line

[0056] 140 External current line

[0057] 200 battery cells

[0058] 210 electrode leads

[0059] 550 Electrical Patterns

[0060] 560, 560A connection part

[0061] D. Depth of the boss hole

[0062] W is the width of the electrical pattern.

Claims

1. A PCB having boss holes in the shape of holes for fixing the PCB substrate, A PCB comprising an electrical pattern arranged along the inner surface of the boss hole.

2. The PCB according to claim 1, wherein the electrical pattern is made of metal.

3. The PCB according to claim 1, wherein the electrical pattern is composed of multiple layers.

4. The PCB according to claim 1, wherein the PCB is located on the upper surface of the PCB and comprises a connecting portion electrically connected to the electrical pattern.

5. It is provided with a vertical gap portion, which is a vertical incision gap extending further from the aforementioned boss hole, The PCB according to claim 1, wherein the electrical pattern extends to the vertical gap.

6. The PCB according to claim 1, wherein two of the electrical patterns are provided on the left and right sides along the inner surface of the boss hole.

7. The PCB according to claim 1, wherein the portion of the electrical pattern that is exposed to the outside is coated with an insulating material.

8. The PCB according to claim 1, wherein the electrical pattern is bonded to the inner surface of the boss hole.

9. The PCB according to claim 1, wherein a ring-shaped protective portion is provided outside the electrical pattern.

10. The PCB according to claim 1, wherein the PCB is used as a battery management unit used in a battery module.

11. A battery module comprising the PCB described in any one of claims 1 to 10.

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