circuit board with tab leads

Abstract

The aim is to achieve both miniaturization and improved mechanical strength of substrates with tab leads. [Solution] The tab-lead substrate 11 comprises a substrate unit 40 having a printed circuit board 20 and electronic components 30 mounted on the printed circuit board 20, a first tab lead 60 and a second tab lead 70 connected to the printed circuit board 20, and a battery 12 positioned alongside the printed circuit board 20 in a first direction L1 perpendicular to the thickness direction T of the printed circuit board 20, and held so as to be sandwiched in the thickness direction T by the first tab lead 60 and the second tab lead 70. The battery 12 has a bottom wall portion 81 of a positive electrode can 80 joined to the first tab lead 60, a bottom wall portion 91 of a negative electrode can 90 joined to the second tab lead 70, and a peripheral wall portion 82 facing the printed circuit board 20 side and conductive to the bottom wall portion 81 of the positive electrode can 80. The first tab lead 60 is in contact with the peripheral wall portion 82 from the printed circuit board 20 side. The second tab lead 70 is separated from the peripheral wall portion 82.

Description

Technical Field

[0001] The present invention relates to a substrate with tab leads.

Background Art

[0002] In an electronic module in which electronic components including various elements and the like are mounted on a substrate, in order to meet the requirements for miniaturization, thinning, etc. of an electronic device or the like on which the electronic module is mounted, further miniaturization, thinning, etc. are required. In particular, considering the application to ultra-small IoT (Internet of Things) devices, the requirements for miniaturization, thinning, etc. of electronic modules are even stronger.

[0003] In a substrate and a battery constituting an electronic module, for example, when the battery is directly mounted on the substrate, a battery with tab leads may be used. A general battery with tab leads includes a positive tab lead electrically connected to the positive electrode side of the battery and a negative tab lead electrically connected to the negative electrode side of the battery (see, for example, Patent Document 1). At least one of the positive tab lead and the negative tab lead is often a tab lead having a Z shape in a side view that is bent and deformed in the middle.

[0004] When mounting such a battery with tab leads on a substrate, for example, as shown in Patent Document 1 below, it is also known to connect a pair of tab leads and the substrate in a state where the battery is housed in a battery housing hole formed in the substrate.

[0005] By the way, in a substrate with tab leads on which a battery with tab leads is mounted, there is a desire for miniaturization. In order to achieve miniaturization of the substrate with tab leads, a configuration in which the substrate and the battery are arranged in the in-plane direction of the substrate can be considered. According to this configuration, compared with a configuration in which the battery is stacked on the substrate or a configuration in which a battery housing hole is formed in the substrate, the substrate can be made smaller than the outer dimensions of the battery, and the entire substrate with tab leads can be miniaturized. In addition, since the battery is not surrounded by the substrate, the heat dissipation of the battery can be ensured.

Prior Art Documents

[0006] [Patent Document 1] Japanese Patent Publication No. 2017-183004 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] However, in a tab-lead substrate where the substrate and battery are arranged in the in-plane direction of the substrate, if the battery is positioned close to the substrate, one tab lead connected to the substrate will come close to the side of the battery that is electrically connected to the other tab lead. This may cause a short circuit in the battery. On the other hand, if the battery is positioned away from the substrate, it is difficult to achieve the miniaturization effect of the tab-lead substrate, and because the battery is supported by the substrate at a position away from the substrate via the tab leads, the load on the tab leads increases, which may cause the tab leads to breakage. Therefore, the development of technology to miniaturize tab-lead substrates is desired.

[0008] Therefore, the present invention aims to achieve both miniaturization and improved mechanical strength of substrates with tab leads. [Means for solving the problem]

[0009] A tab-lead substrate according to a first aspect of the present invention comprises a substrate unit having a substrate and electronic components mounted on the substrate, a first tab lead and a second tab lead connected to the substrate, and a battery arranged alongside the substrate in a first direction perpendicular to the thickness direction of the substrate and held so as to be sandwiched in the thickness direction by the first tab lead and the second tab lead, wherein the battery has a first pole joined to the first tab lead, a second pole joined to the second tab lead, and a side portion facing the substrate side and conductive to the first pole, the first tab lead contacting the side portion from the substrate side, and the second tab lead being away from the side portion.

[0010] According to the first embodiment, the substrate and the battery can be positioned close together in the first direction, which is the in-plane direction of the substrate, while avoiding contact between the side of the battery and the second tab lead, thereby reducing the dimensions of the tab-lead substrate in the first direction. Furthermore, since the first tab lead is in contact with the side of the battery from the substrate side, the battery is stably supported by the first tab lead compared to a configuration in which the first tab lead is not in contact with the side of the battery. As a result, the load on the first tab lead is reduced, damage to the first tab lead can be suppressed, and consequently, a tab-lead substrate in which the battery is firmly held can be formed. Therefore, it is possible to achieve both miniaturization and improved mechanical strength of the tab-lead substrate.

[0011] A tab-lead substrate according to a second aspect of the present invention is a tab-lead substrate according to the first aspect, wherein the first tab lead has a first substrate bonding portion bonded to the substrate, a first battery bonding portion bonded to the first electrode, and a first intermediate portion located between the first substrate bonding portion and the first battery bonding portion and extending along the thickness direction, wherein the first intermediate portion may be in contact with the side portion.

[0012] According to the second embodiment, the side portion of the battery is precisely aligned with the first intermediate portion, so that variations in the dimensions of the substrate with tab leads in the first direction can be suppressed.

[0013] A tab-lead substrate according to a third aspect of the present invention is a tab-lead substrate according to the second aspect, wherein the second tab-lead has a second substrate bonding portion bonded to the substrate, a second battery bonding portion bonded to the second electrode, and a second intermediate portion located between the second substrate bonding portion and the second battery bonding portion, extending from the second substrate bonding portion toward the first battery bonding portion along the thickness direction, wherein the second intermediate portion may face the side portion with a gap between them.

[0014] According to the third embodiment, the battery can be placed within the thickness range of the substrate, and it is possible to suppress the battery from protruding significantly in one direction from one side of the substrate. Therefore, the entire substrate with tab leads can be made thinner.

[0015] A tab-lead substrate according to a fourth aspect of the present invention is a tab-lead substrate according to the third aspect, wherein the second intermediate portion may be located inward from the edge of the substrate when viewed in the thickness direction.

[0016] According to the fourth embodiment, since the edge of the substrate is located between the second intermediate portion and the side portion of the battery in the first direction, the edge of the substrate can restrict the side portion of the battery from approaching the second intermediate portion. Therefore, contact between the second intermediate portion and the side portion of the battery can be reliably suppressed.

[0017] A tab-lead substrate according to a fifth aspect of the present invention is a tab-lead substrate according to any of the first to fourth aspects described above, wherein the battery may be located at one end in the first direction.

[0018] According to the fifth embodiment, the dimensions of the tab-lead substrate in the first direction change depending on the position of the battery relative to the substrate. That is, the tab-lead substrate can be miniaturized in the first direction simply by bringing the battery closer to the substrate. Therefore, a tab-lead substrate that can effectively exert the above effects can be obtained.

[0019] A tab-lead substrate according to a sixth aspect of the present invention is a tab-lead substrate according to the third aspect or any of the above aspects referencing it, wherein the dimension in the thickness direction of the first intermediate portion may be larger than the dimension in the thickness direction of the second intermediate portion.

[0020] According to the sixth aspect, compared with the configuration in which the dimension in the thickness direction of the first intermediate portion is less than or equal to the dimension in the thickness direction of the second intermediate portion, the dimension of the contact portion between the first tab lead and the side surface portion of the battery in the thickness direction can be ensured to be large. Thereby, the battery is supported in a stable state by the first tab lead. Therefore, a substrate with a tab lead in which the battery is more firmly held can be formed.

[0021] The substrate with a tab lead according to the seventh aspect of the present invention is the substrate with a tab lead according to the third aspect or any of the aspects cited above, wherein the substrate has a mounting surface to which the first substrate bonding portion and the second substrate bonding portion are connected, and the first intermediate portion may be in contact with an edge of the substrate.

[0022] According to the seventh aspect, since the first tab lead is less likely to be displaced with respect to the substrate when the first intermediate portion contacts the edge of the substrate, the first tab lead can be firmly connected to the substrate. Therefore, a substrate with a tab lead in which the battery is firmly supported via the first tab lead can be formed.

Advantages of the Invention

[0023] According to the present invention, it is possible to achieve both miniaturization of the substrate with a tab lead and improvement of mechanical strength.

Brief Description of the Drawings

[0024] [Figure 1] It is a side view of a battery module according to the first embodiment. [Figure 2] It is an enlarged plan view showing a substrate with a tab lead according to the first embodiment. [Figure 3] It is a side view of a substrate with a tab lead according to the second embodiment.

Modes for Carrying Out the Invention

[0025] Hereinafter, embodiments of the tab-lead substrate and battery module according to the present invention will be described with reference to the drawings. In the following description, components having the same or similar functions will be denoted by the same reference numerals. Duplication of these components may be omitted.

[0026] [First Embodiment] Figure 1 is a side view of a battery module according to the first embodiment. As shown in Figure 1, the battery module 10 of this embodiment comprises a substrate 11 with tab leads and a resin molded portion 13. In Figure 1, the resin molded portion 13 is shown in a cross-sectional view to represent the substrate 11 with tab leads inside the battery module 10.

[0027] In the battery module 10 of this embodiment, multiple electronic components 30 constituting the battery module 10 are mounted on a printed circuit board 20, which will be described later. At least one of these electronic components 30 includes a functional component (not shown). This functional component may be, for example, a SoC (system-on-a-chip) that includes communication and control functions. Therefore, the battery module 10 itself functions as an electronic module.

[0028] (Circuit board with tab leads) The tab-lead substrate 11 comprises a substrate unit 40 having a printed wiring board 20 and various electronic components 30 mounted on the printed wiring board 20, a battery holder 50 connected to the printed wiring board 20, and a battery 12 held in the battery holder 50. The substrate unit 40 and the battery 12 are aligned in a first direction L1 perpendicular to the thickness direction T of the printed wiring board 20. The battery 12 is located at one end of the tab-lead substrate 11 in the first direction L1, and the printed wiring board 20 is located at the other end. Hereinafter, the direction perpendicular to the thickness direction T and the first direction L1 will be referred to as the second direction L2. Note that the direction perpendicular to the thickness direction T may be referred to as the in-plane direction if it is not limited to the first direction L1 or the second direction L2. Furthermore, of the two directions that are parallel to the thickness direction T and facing opposite directions, one is defined as the front side, and the direction opposite to the front side is defined as the back side.

[0029] The printed circuit board 20 is an example of a "circuit board". The printed circuit board 20 comprises an insulating blank substrate 21 and printed wiring (first printed wiring 22 and second printed wiring 23) formed on the blank substrate 21. The printed circuit board 20 is formed in a rectangular shape when viewed from the thickness direction T in a plan view. The printed circuit board 20 has a plan view shape with the first direction L1 as the longitudinal direction and the second direction L2 as the short direction. However, the shape of the printed circuit board 20 is not limited to a rectangular shape in a plan view and may be changed as appropriate. The printed circuit board 20 has a battery-side edge 26 that faces the battery 12 in the in-plane direction. The battery-side edge 26 is one edge of the printed circuit board 20 in the first direction L1 and extends in the second direction L2.

[0030] The raw substrate 21 is a flat, rigid substrate having a uniform thickness throughout, and has a first main surface 21a facing the front side and a second main surface 21b facing the back side.

[0031] Multiple first printed circuit boards 22 are formed on the first main surface 21a of the raw substrate 21. The first printed circuit boards 22 are formed using a conductive material such as copper or gold to form a predetermined circuit pattern. The surface of the first printed circuit boards 22 functions as the first mounting surface 22a. Similarly, multiple second printed circuit boards 23 are formed using a conductive material on the second main surface 21b of the raw substrate 21 to form a predetermined circuit pattern. The surface of the second printed circuit boards 23 functions as the second mounting surface 23a.

[0032] Figure 2 is a plan view showing an enlarged view of a substrate with tab leads according to the first embodiment. As shown in Figure 2, the printed circuit board includes a first terminal 24 connected to the positive terminal of the battery 12 and a second terminal 25 connected to the negative terminal of the battery 12. The first terminal 24 and the second terminal 25 are formed on the first mounting surface 22a. The first terminal 24 and the second terminal 25 are arranged side by side in a second direction L2 along the battery-side edge 26 of the printed circuit board 20. The first terminal 24 and the second terminal 25 are arranged on opposite sides of the center of the printed circuit board 20 in the second direction L2.

[0033] Furthermore, the multiple first printed wirings 22 and the multiple second printed wirings 23 may be electrically connected as appropriate via through-electrodes (not shown) that penetrate the raw substrate 21 in the thickness direction T. In addition, the printed substrate 20 may be configured as a multilayer substrate such as a through-layer substrate or a build-up substrate.

[0034] The electronic components 30 include, for example, active elements (including various semiconductor elements such as transistors and diodes), passive elements (including resistors, capacitors, and condensers), functional components such as integrated circuits, piezoelectric elements, safety components such as fuses, and auxiliary components such as relays and switches. These various electronic components 30 are mounted on the first mounting surface 22a and the second mounting surface 23a, respectively, using solder or the like, and are fixed in a state of electrical conductivity with the first printed circuit board 22 and the second printed circuit board 23.

[0035] Figure 1 schematically illustrates the electronic components 30 to be mounted on the first mounting surface 22a and the second mounting surface 23a. Furthermore, the size, arrangement, number, etc. of the electronic components 30 to be mounted may be appropriately changed according to the functions required of the battery module 10.

[0036] The board unit 40 is a so-called printed circuit board, which functions as an electronic circuit by mounting multiple electronic components 30 on the printed circuit board 20 described above.

[0037] The battery holder 50 has a first tab lead 60 and a second tab lead 70 connected to the printed circuit board 20. The first tab lead 60 and the second tab lead 70 are connected to the first mounting surface 22a of the printed circuit board 20. As a result, the first tab lead 60 and the second tab lead 70 are fixed in a state of electrical connection to the first printed wiring 22. The method of connecting the first tab lead 60 and the second tab lead 70 to the first mounting surface 22a is not particularly limited, but for example, soldering, thermocompression bonding, ultrasonic welding, etc., can be used.

[0038] The first tab lead 60 is formed in a Z-shape in side view by press forming or bending a metal plate with excellent conductivity, such as copper, using a molding die (not shown). The thickness of the first tab lead 60 is uniform throughout. However, this is not the only case; for example, it may be formed with varying thickness in certain areas.

[0039] The first tab lead 60 has a first substrate-side end (first substrate-side joint) 61 joined to the printed circuit board, a first battery-side end (first battery-side joint) 62 joined to the battery 12, and a first intermediate portion 63 located between the first substrate-side end 61 and the first battery-side end 62.

[0040] The first substrate-side end 61 is positioned facing the surface of the printed circuit board 20 and is connected to the first terminal 24 on the first mounting surface 22a. The entire first substrate-side end 61 is positioned inward (closer to the center of the raw substrate 21) in a plan view from the battery-side edge 26 of the printed circuit board 20. The first substrate-side end 61 extends along the in-plane direction. The first battery-side end 62 is positioned outward in a plan view from the battery-side edge 26 of the printed circuit board 20 and is positioned offset to the back side relative to the first substrate-side end 61. The first battery-side end 62 extends along the in-plane direction.

[0041] The first intermediate portion 63 extends along the thickness direction T from one end connected to the first substrate-side end 61 to the other end connected to the first battery-side end 62. The first intermediate portion 63 extends to the back side along the thickness direction T so as to straddle the battery-side edge 26 of the printed circuit board 20. The first intermediate portion 63 is in contact with the battery-side edge 26 of the printed circuit board 20. However, the first intermediate portion 63 may be separated from the battery-side edge 26 of the printed circuit board 20. In the illustrated example, the first intermediate portion 63 extends approximately parallel to the thickness direction T, but the first intermediate portion 63 only needs to straddle the battery-side edge 26 of the printed circuit board 20, and may extend to the back side and outward in the in-plane direction as it moves from one end connected to the first substrate-side end 61 to the other end connected to the first battery-side end 62.

[0042] The first tab lead 60, which is bent into a Z-shape in side view, is cantilevered and held by being connected to the first mounting surface 22a via the first substrate-side end 61, such that the first battery-side end 62 is positioned outside the printed circuit board 20.

[0043] The second tab lead 70 is formed in a Z-shape in side view by press forming or bending a metal plate with excellent conductivity, such as copper, using a molding die (not shown). The thickness of the second tab lead 70 is uniform throughout. However, this is not limited to this case, and it may be formed with varying thickness in certain areas, for example.

[0044] The second tab lead 70 has a second substrate-side end (second substrate-side joint) 71 joined to the printed circuit board, a second battery-side end (second battery-side joint) 72 joined to the battery 12, and a second intermediate portion 73 located between the second substrate-side end 71 and the second battery-side end 72.

[0045] The second substrate-side end 71 is positioned facing the surface of the printed circuit board 20 and is connected to the second terminal 25 on the first mounting surface 22a. The entirety of the second substrate-side end 71 is positioned inward in a plan view from the battery-side edge 26 of the printed circuit board 20. The second substrate-side end 71 extends along the in-plane direction. The second battery-side end 72 is positioned such that at least a portion of it is located outward in a plan view from the battery-side edge 26 of the printed circuit board 20 and is positioned offset to the front side relative to the second substrate-side end 71. The second battery-side end 72 extends along the in-plane direction.

[0046] The second intermediate portion 73 extends along the thickness direction T from one end connected to the second substrate-side end 71 to the other end connected to the second battery-side end 72. The second intermediate portion 73 extends from the second substrate-side end 71 toward the side away from the first battery-side end 62 (the front side) along the thickness direction T. For example, the entirety of the second intermediate portion 73 is positioned inward in a plan view from the battery-side edge 26 of the printed circuit board 20. The dimension of the second intermediate portion 73 in the thickness direction T is smaller than the dimension of the first intermediate portion 63 in the thickness direction T. In the illustrated example, the second intermediate portion 73 extends approximately parallel to the thickness direction T, but the second intermediate portion 73 only needs to be inclined with respect to the in-plane direction, and for example, it may extend toward the front side and outward in the in-plane direction as it moves from one end connected to the second substrate-side end 71 toward the other end connected to the second battery-side end 72.

[0047] The second tab lead 70, which is bent into a Z shape in side view, is cantilevered and held by being connected to the first mounting surface 22a via the second substrate side end 71, such that the second battery side end 72 is positioned outside the printed circuit board 20.

[0048] In the illustrated example, the ends of the first tab lead 60 and the second tab lead 70 are formed in a rectangular shape in plan view, but the explanation is not limited to this case. For example, the ends of the tab leads may be formed in a circular, elliptical, polygonal, or other shape in plan view.

[0049] The first tab lead 60 and the second tab lead 70 are positioned outside the printed circuit board 20, and are capable of holding the battery 12 between the battery-side ends 62 and 72. Furthermore, the first tab lead 60 and the second tab lead 70 are arranged parallel to each other in a plan view along a first direction L1. The first battery-side end 62 and the second battery-side end 72 are arranged to overlap each other in a plan view. The first board-side end 61 and the second board-side end 71 are arranged with a gap between them in a second direction L2 in a plan view.

[0050] The first intermediate section 63 and the second intermediate section 73 are positioned offset from each other in the second direction L2. The first intermediate section 63 and the second intermediate section 73 are positioned on opposite sides of the center of the printed circuit board 20 in the second direction L2. As a result, the entirety of the first intermediate section 63 and the second intermediate section 73 are positioned offset from the center of the printed circuit board 20 in the second direction L2.

[0051] As shown in Figures 1 and 2, the battery 12 is a so-called coin (button) type battery having a predetermined diameter and thickness. The battery 12 is, for example, thicker than the printed circuit board 20. The battery 12 may be a primary battery such as a lithium battery or a silver oxide battery, or a secondary battery such as a non-aqueous electrolyte secondary battery.

[0052] The battery 12 has a positive electrode can 80 and a negative electrode can 90. The positive electrode can 80 is formed in a bottomed cylindrical shape and has a bottom wall portion 81 that forms one end face of the battery 12 and a peripheral wall portion 82 that forms the outer circumferential surface of the battery 12. The bottom wall portion 81 is the positive electrode of the battery 12 and is an example of a "first electrode". The peripheral wall portion 82 is an example of a "side portion" that is conductive to the positive electrode of the battery 12. The negative electrode can 90 is formed in a bottomed cylindrical shape and is inserted inside the peripheral wall portion 82 of the positive electrode can 80. The negative electrode can 90 has a bottom wall portion 91 that forms the other end face of the battery 12. The bottom wall portion 91 is the negative electrode of the battery 12 and is an example of a "second electrode". The battery 12 is arranged with both end faces oriented in the thickness direction T.

[0053] The battery 12 is positioned such that at least a portion of it overlaps with the printed circuit board 20 in a first direction L1 when viewed from above. In this embodiment, the center position of the battery 12 and the center position of the printed circuit board 20 coincide in a second direction L2. At least a portion of the battery 12 is located within the thickness range of the printed circuit board 20 along the thickness direction T.

[0054] The battery 12 is held outside the printed circuit board 20 by being sandwiched in the thickness direction T between the first battery-side end 62 of the first tab lead 60 and the second battery-side end 72 of the second tab lead 70. As a result, the battery 12 is mechanically held by the first tab lead 60 and the second tab lead 70 with its electrodes electrically connected to them. Therefore, the first tab lead 60 and the second tab lead 70 also function as lead terminals for the electrodes of the battery 12.

[0055] The positive electrode casing 80 of battery 12 is electrically connected to the first tab lead 60. The negative electrode casing 90 of battery 12 is electrically connected to the second tab lead 70. Therefore, the first tab lead 60 functions as the positive lead terminal, and the second tab lead 70 functions as the negative lead terminal.

[0056] A first fixing portion 65 is provided between the first battery-side end 62 of the first tab lead 60 and the bottom wall portion 81 of the positive electrode can 80, joining the first tab lead 60 and the positive electrode can 80 together. Similarly, a second fixing portion 75 is provided between the second battery-side end 72 of the second tab lead 70 and the bottom wall portion 91 of the negative electrode can 90, joining the second tab lead 70 and the negative electrode can 90 together. Each fixing portion 65, 75 is a welded portion formed by spot welding or the like, or a welded portion formed by high-frequency welding or the like. The relative positional relationship between the first fixing portion 65 and the second fixing portion 75 is not particularly limited.

[0057] The peripheral wall portion 82 of the positive electrode can 80 and the battery-side edge 26 of the printed circuit board 20 face each other in a first direction L1. The peripheral wall portion 82 of the positive electrode can 80 contacts the first intermediate portion 63 of the first tab lead 60 from the outside of the printed circuit board 20. The peripheral wall portion 82 of the positive electrode can 80 contacts the first intermediate portion 63 in a first direction L1. That is, the peripheral wall portion 82 and the first intermediate portion 63 of the positive electrode can 80 are in contact with each other at a point where they overlap when viewed from the first direction L1. As a result, the displacement of the positive electrode can 80 toward the printed circuit board 20 is restricted by the first intermediate portion 63. In this embodiment, since the first intermediate portion 63 extends in a second direction L2, the contact portion between the first intermediate portion 63 and the cylindrical peripheral wall portion 82 of the positive electrode can 80 has substantially no width in the second direction L2. However, the first intermediate portion 63 may be curved along the peripheral wall portion 82 of the positive electrode can 80 and may be in contact with the peripheral wall portion 82 of the positive electrode can 80 with a width in the second direction L2.

[0058] In the illustrated example, the peripheral wall portion 82 of the positive electrode can 80 is not in contact with the printed circuit board 20. However, the peripheral wall portion 82 of the positive electrode can 80 may be in contact with the edge of the printed circuit board 20. For example, in this embodiment, since the first intermediate portion 63 is located offset from the center of the battery 12 in the second direction L2, the center of the peripheral wall portion 82 of the positive electrode can 80 in the second direction L2 can be brought into contact with the battery-side edge 26 of the printed circuit board 20.

[0059] (Resin molded part) The resin molded portion 13 is formed by molding a resin for mold sealing to have a predetermined external shape. The resin for mold sealing is not particularly limited, but for example, a thermosetting resin such as epoxy resin can be used. The molding method for the resin molded portion 13 is not particularly limited, but for example, a molding method similar to injection molding, such as transfer molding, can be used.

[0060] The resin molded portion 13 is formed to cover the entire substrate 11 with tab leads from the outside, sealing them inside. The resin constituting the resin molded portion 13 may contain metal fillers or the like to adjust properties such as heat dissipation and thermal expansion coefficient.

[0061] As described above, the battery 12 of this embodiment faces the printed circuit board 20 and has a peripheral wall portion 82 of a positive electrode casing 80 that is conductive to the positive electrode. The first tab lead 60 is in contact with the peripheral wall portion 82 from the printed circuit board 20 side. The second tab lead 70 is away from the peripheral wall portion 82. With this configuration, contact between the peripheral wall portion 82 of the battery 12 and the second tab lead 70 can be avoided, and the printed circuit board 20 and the battery 12 can be positioned closer together in the first direction L1, which is the in-plane direction of the printed circuit board 20, thereby reducing the dimensions of the tab lead-equipped substrate 11 in the first direction L1. Furthermore, since the first tab lead 60 is in contact with the peripheral wall portion 82 of the battery 12 from the printed circuit board 20 side, the battery 12 is stably supported by the first tab lead 60 compared to a configuration in which the first tab lead 60 is not in contact with the peripheral wall portion 82 of the battery 12. This reduces the load on the first tab lead 60, suppresses damage to the first tab lead 60, and consequently enables the formation of a tab-lead substrate 11 in which the battery 12 is firmly held. Therefore, it is possible to achieve both miniaturization and improved mechanical strength of the tab-lead substrate 11.

[0062] The first tab lead 60 has a first substrate-side end 61 joined to the printed circuit board 20, a first battery-side end 62 joined to the first pole, and a first intermediate portion 63 located between the first substrate-side end 61 and the first battery-side end 62 and extending along the thickness direction T. The first intermediate portion 63 is in contact with the peripheral wall portion 82 of the battery 12. With this configuration, the peripheral wall portion 82 of the battery 12 is in contact with the first intermediate portion 63, so that variations in the dimensions of the tab lead substrate 11 in the first direction L1 can be suppressed.

[0063] The second tab lead 70 has a second substrate-side end 71 joined to the printed circuit board 20, a second battery-side end 72 joined to the second electrode, and a second intermediate portion 73 located between the second substrate-side end 71 and the second battery-side end 72, extending from the second substrate-side end 71 toward the side away from the first battery-side end 62 along the thickness direction T. The second intermediate portion 73 faces the peripheral wall portion 82 with a gap between them. With this configuration, the battery 12 can be placed within the thickness range of the printed circuit board 20, and it is possible to suppress the battery 12 from protruding significantly from one side of the printed circuit board 20 toward one side in the thickness direction T. Therefore, the entire tab lead substrate 11 can be made thinner.

[0064] The second intermediate portion 73 is located inward from the battery-side edge 26 of the printed circuit board 20 in a plan view. With this configuration, in the first direction L1, the battery-side edge 26 of the printed circuit board 20 is located between the second intermediate portion 73 and the peripheral wall portion 82 of the battery 12, so that the peripheral wall portion 82 of the battery 12 does not approach the second intermediate portion 73, which can be restricted by the battery-side edge 26 of the printed circuit board 20. Therefore, contact between the second intermediate portion 73 and the peripheral wall portion 82 of the battery 12 can be reliably suppressed.

[0065] The battery 12 is located at one end of the tab-lead substrate 11 in the first direction L1. With this configuration, the dimensions of the tab-lead substrate 11 in the first direction L1 change depending on the position of the battery 12 relative to the printed circuit board 20. In other words, the tab-lead substrate 11 can be miniaturized in the first direction L1 by moving the battery 12 closer to the printed circuit board 20. Therefore, a tab-lead substrate 11 can be obtained that can effectively exhibit the above-mentioned effects.

[0066] The dimension of the first intermediate portion 63 in the thickness direction T is larger than the dimension of the second intermediate portion 73 in the thickness direction T. With this configuration, compared to a configuration in which the dimension of the first intermediate portion 63 in the thickness direction T is less than or equal to the dimension of the second intermediate portion 73 in the thickness direction T, a larger contact area between the first tab lead 60 and the peripheral wall portion 82 of the battery 12 can be secured in the thickness direction T. As a result, the battery 12 is supported in a stable state by the first tab lead 60. Therefore, a substrate 11 with tab leads in which the battery 12 is held more firmly can be formed.

[0067] The first intermediate portion 63 is in contact with the battery-side edge 26 of the printed circuit board 20. With this configuration, the contact of the first intermediate portion 63 with the battery-side edge 26 of the printed circuit board 20 makes the first tab lead 60 less susceptible to displacement relative to the printed circuit board 20, thus allowing the first tab lead 60 to be firmly connected to the printed circuit board 20. Therefore, a tab-lead substrate 11 can be formed in which the battery 12 is firmly supported on the printed circuit board 20 via the first tab lead 60.

[0068] Furthermore, the peripheral wall portion 82 of the positive electrode can 80 may be brought into contact with the battery-side edge 26 of the printed circuit board 20, allowing the battery 12 to be positioned as close to the printed circuit board 20 as possible, and enabling miniaturization of the tab-lead circuit board 11 in the first direction L1.

[0069] [Second Embodiment] Next, a second embodiment will be described with reference to Figure 3. The second embodiment differs from the first embodiment in that the first intermediate portion 63A of the first tab lead 60A does not straddle the battery-side edge 26 of the printed circuit board 20. Other than what is described below, the configuration is the same as that of the first embodiment.

[0070] Figure 3 is a side view of a substrate with tab leads according to the second embodiment. As shown in Figure 3, the battery holder 50 is equipped with a first tab lead 60A in place of the first tab lead 60 of the first embodiment.

[0071] The first tab lead 60A is connected to the second mounting surface 23a of the printed circuit board 20. As a result, the first tab lead 60A is fixed in a state of electrical connection to the second printed wiring 23. In this embodiment, the first terminal 24 of the printed wiring is formed on the second mounting surface 23a. The first tab lead 60A has a first board-side end 61 connected to the printed wiring, a first battery-side end 62 connected to the battery 12, and a first intermediate portion 63A located between the first board-side end 61 and the first battery-side end 62.

[0072] The first substrate-side end 61 is positioned facing the back surface of the printed circuit board 20 and is connected to the first terminal 24 on the second mounting surface 23a. The first intermediate portion 63A extends in a direction away from the printed circuit board 20 along the thickness direction T, from one end connected to the first substrate-side end 61 to the other end connected to the first battery-side end 62. The first intermediate portion 63A is positioned outside the battery-side edge 26 of the printed circuit board 20 in a plan view. In the illustrated example, the first intermediate portion 63A extends approximately parallel to the thickness direction T, but for example, the first intermediate portion 63A may extend outward in the in-plane direction and towards the back surface as it moves from one end connected to the first substrate-side end 61 to the other end connected to the first battery-side end 62.

[0073] The peripheral wall portion 82 of the positive electrode can 80 is in contact with the first intermediate portion 63A of the first tab lead 60A from the outside of the printed circuit board 20. The peripheral wall portion 82 of the positive electrode can 80 is in contact with the first intermediate portion 63A in a first direction L1. That is, the peripheral wall portion 82 and the first intermediate portion 63A of the positive electrode can 80 are in contact with each other at a point where they overlap when viewed from the first direction L1. As a result, the displacement of the positive electrode can 80 toward the printed circuit board 20 is restricted by the first intermediate portion 63A. The peripheral wall portion 82 of the positive electrode can 80 may or may not be in contact with the battery-side edge 26 of the printed circuit board 20.

[0074] This embodiment provides the same effects as the first embodiment. In addition, this embodiment provides the following effects. Since the first intermediate portion 63A of the first tab lead 60A does not straddle the battery-side edge 26 of the printed circuit board 20, the first tab lead 60A is not interposed between the battery-side edge 26 of the printed circuit board 20 and the first intermediate portion 63A. This makes it easier to bring the peripheral wall portion 82 of the positive electrode can 80 into contact with the battery-side edge 26 of the printed circuit board 20. Therefore, the battery 12 can be positioned as close to the printed circuit board 20 as possible, and the tab-lead substrate 11 can be miniaturized in the first direction L1.

[0075] In the second embodiment, the relative positional relationship of the first tab lead 60A and the second tab lead 70 in the second direction L2 is not particularly limited. For example, the first intermediate portion 63A and the second intermediate portion 73 may be offset from each other in the second direction L2, or the regions in which they are located may overlap in the second direction L2.

[0076] It should be noted that the present invention is not limited to the embodiments described above with reference to the drawings, and various modifications are conceivable within its technical scope. For example, in the above embodiment, the second tab lead 70 has a second intermediate portion 73 that extends along the thickness direction T, but the configuration is not limited to this. For example, the second tab lead may extend along the in-plane direction from the second substrate side end to the second battery side end.

[0077] In the above embodiment, the second intermediate portion 73 of the second tab lead 70 is positioned inward in a plan view from the battery-side edge 26 of the printed circuit board 20, but the configuration is not limited to this. The second intermediate portion 73 only needs to be positioned inward in a plan view from the first intermediate portions 63, 63A of the first tab leads 60, 60A, and at least a part of the second intermediate portion 73 may be positioned outward in a plan view from the battery-side edge 26 of the printed circuit board 20.

[0078] Furthermore, it is possible to replace the components in the above-described embodiments with well-known components as appropriate, without departing from the spirit of the present invention. [Explanation of Symbols]

[0079] 11...Substrate with tab leads 12...Battery 20...Printed circuit board (substrate) 22a...First mounting surface (mounting surface) 26...Battery side edge (edge) 30...Electronic component 40...Substrate unit 60,60A...First tab lead 61...First substrate side end (first substrate joint) 62...First battery side end (first battery joint) 63,63A...First intermediate section 70...Second tab lead 71...Second substrate side end (second substrate joint) 72...Second battery side end (second battery joint) 73...Second intermediate section 81...Bottom wall (first pole) 82...Peripheral wall (side) 91...Bottom wall (second pole) L1...First direction T...Thickness direction

Claims

1. A substrate unit having a substrate and electronic components mounted on the substrate, A first tab lead and a second tab lead connected to the substrate, A battery is positioned alongside the substrate in a first direction perpendicular to the thickness direction of the substrate and held by the first tab lead and the second tab lead so as to be sandwiched in the thickness direction, Equipped with, The aforementioned battery is The first pole joined to the first tab lead, The second pole joined to the second tab lead, The side portion facing the substrate side and connected to the first pole, It has, The first tab lead contacts the side portion from the substrate side, The second tab lead is separated from the side portion. Circuit board with tab leads.

2. The first tab lead is, A first substrate bonding portion bonded to the aforementioned substrate, The first battery junction connected to the first electrode, A first intermediate portion located between the first substrate bonding portion and the first battery bonding portion, extending along the thickness direction, It has, The first intermediate portion is in contact with the side portion. A substrate with tab leads according to claim 1.

3. The second tab lead is, A second substrate bonding portion bonded to the aforementioned substrate, The second battery junction connected to the second electrode, A second intermediate portion is located between the second substrate joint and the second battery joint, and extends from the second substrate joint toward the first battery joint along the thickness direction, It has, The second intermediate portion is opposite the side portion with a gap between them. A substrate with tab leads according to claim 2.

4. The second intermediate portion is located inward from the edge of the substrate when viewed in the thickness direction. A substrate with tab leads as described in claim 3.

5. At one end in the first direction, the battery is located A substrate with tab leads according to claim 1 or claim 2.

6. The dimension in the thickness direction of the first intermediate portion is larger than the dimension in the thickness direction of the second intermediate portion. A substrate with tab leads as described in claim 3.

7. The substrate has a mounting surface to which the first substrate bonding portion and the second substrate bonding portion are connected. The first intermediate portion is in contact with the edge of the substrate. A substrate with tab leads according to claim 3 or claim 6.

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