Electronic component and method of manufacturing the same

Abstract

To provide an electronic component that is enhanced in connectivity of a terminal member and explosion proofing function of an explosion-proof valve, and a method of manufacturing the same.SOLUTION: An electronic component includes: a case (4) which houses an element; a first case face part (base part 6-1) set for the case; a second case face part (protrusion base part 6-2) protruded from the first case face part; a standing wall part (6-4) connecting with the first case face part and second case face part; and an explosion-proof valve (10) which is installed at the second case face part, and is opened as the internal pressure in the case rises to discharge gas from the case.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to electronic components, such as capacitors, condensers, batteries, etc., that include explosion-proof valves and methods for manufacturing the same. [Background technology]

[0002] It is already known that in this type of electronic component, the internal pressure of the case rises due to the gas that fills the case during operation, and an explosion-proof valve is provided to prevent deformation of the case and sudden gas discharge. When the internal pressure of the case exceeds a predetermined pressure, the explosion-proof valve is quickly opened to quickly discharge the gas from the case, thereby avoiding unexpected events. This explosion-proof valve is provided on the case side or in the sealing material that seals the case.

[0003] Regarding electronic components equipped with such explosion-proof valves, a case structure equipped with an explosion-proof mechanism by providing a plurality of grooves on the bottom of an electricity storage device is known (for example, Patent Document 1, paragraphs 0050 and 0051).

[0004] It is known that an explosion-proof mechanism is achieved by providing a sealing plate that seals the case with a thin rubber layer that blocks the through-hole (for example, Patent Document 2, FIG. 1 and its explanation).

[0005] Moreover, terminal members are attached to the body of the electronic component, for example, a case, and these terminal members are used to fix the electronic component to a board or to connect components together.

[0006] Regarding fixing electronic components, it is known to provide mounting legs on protrusions provided on the case (for example, Patent Document 3). Also, for axial-type electronic components, it is known to place metal members on both ends of the case and connect lead wires to each metal member to fix and electrically connect to the board (for example, Patent Document 4). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2019-145478 A [Patent Document 2] Jpn. Jpn. Published No. 51-8679 [Patent Document 3] Japanese Utility Model Application Publication No. 55-122334 [Patent Document 4] Japanese Utility Model Application Publication No. 50-106654 Summary of the Invention [Problem to be solved by the invention]

[0008] In electronic components such as capacitors, condensers, and batteries, the explosion-proof function of the explosion-proof valve is essential to ensure the reliability of the electronic components. For example, the explosion-proof valve formed in an aluminum case is affected by the functional range of the explosion-proof valve and the thickness of the stress surface to which the internal pressure of the case acts.

[0009] For example, in the case of an axial type electronic component, it is necessary to provide a terminal member on the case side. The terminal member is generally connected by a method such as welding. It is known that welding causes distortion not only at the connection points of the case member and the terminal member but also in the surrounding area. For this reason, if stress caused by welding is applied to the functional area of ​​the explosion-proof valve, the function of the explosion-proof valve may be affected.

[0010] In view of these issues, if the functional area of ​​the explosion-proof valve is reduced, the specified explosion-proof function cannot be obtained, and there is also the issue that moving the explosion-proof valve away from the welding points increases the case volume, preventing the miniaturization and compactification of electronic components.

[0011] In view of such problems, the inventors of the present disclosure have discovered that by strengthening the area around the functional area of ​​the explosion-proof valve, the reliability of the explosion-proof function can be improved and the effects of welding of the terminal members connected to the case can also be avoided.

[0012] Therefore, an object of the present disclosure is to provide an electronic component and a manufacturing method thereof that improve the connectivity of the terminal members and the reliability of the explosion-proof function of the explosion-proof valve. [Means for solving the problem]

[0013] In order to achieve the above object, the electronic component of the present disclosure includes a case for accommodating an element, a first case surface portion set on the case, a second case surface portion protruding from the first case surface portion, a vertical wall portion connecting the first case surface portion and the second case surface portion, and an explosion-proof valve provided on the second case surface portion that opens when the internal pressure of the case increases to release gas from the case. Contains:

[0014] The electronic component may further include a terminal member connected to the case, the terminal member being welded to at least the vertical wall portion.

[0015] In this electronic component, the terminal member may be further welded to the first case surface portion.

[0016] In this electronic component, the standing wall portion or the first case surface portion may be thicker than the second case surface portion.

[0017] In this electronic component, a peripheral edge portion of the second case surface portion may be reinforced by the vertical wall portion, and further reinforced by a welded portion to the terminal member.

[0018] In this electronic component, the length over which the terminal member and the standing wall portion butt against each other may be at least a quarter or more than a quarter of the circumferential length of the standing wall portion.

[0019] In order to achieve the above-mentioned objective, according to the manufacturing method for electronic components disclosed herein, the method includes a step of forming a case using a case member, forming a first case surface portion and a second case surface portion on the case, as well as a vertical wall portion connecting the first case surface portion and the second case surface portion, and a step of forming an explosion-proof valve on the second case surface portion.

[0020] Any of the methods for manufacturing an electronic component may further include the step of welding a terminal member to at least the standing wall portion, or to the standing wall portion and the first case surface portion. Effect of the Invention

[0021] According to the electronic component of the present disclosure, any one of the following effects can be obtained. (1) The first case surface portion and the second case surface portion can be connected by the vertical wall portion, and a terminal member can be connected to the vertical wall portion, thereby improving the explosion-proof function of the explosion-proof valve and its connectivity with the terminal member, the reliability of the explosion-proof function, and the connectivity with the terminal member, thereby improving the reliability of the electronic component.

[0022] (2) The terminal members can be connected to the vertical wall portion by welding, for example, by laser welding, which prevents the connection of the terminal members from affecting the explosion-proof portion including the explosion-proof valve, and prevents a decrease in the explosion-proof function due to the connection of the terminal members.

[0023] (3) When the terminal members are connected to the vertical wall portions, the terminal members can be positioned relative to the case by the vertical wall portions, and the terminal members can be firmly connected to the vertical wall portions.

[0024] (4) The increase in internal pressure inside the case can be concentrated on the second case face side, preventing deformation of the case, including the first case face, due to the increase in internal pressure, and by opening the explosion-proof valve, gas can be quickly released from inside the case into the atmosphere.

[0025] (5) The terminal member can be placed on the first case surface portion and connected to the upright wall portion, and the terminal member can be supported by the first case surface portion, thereby enhancing the stability of the terminal member.

[0026] (6) If a gap is provided between the terminal member and the first case surface portion, expanded air can be released when the terminal member and the vertical wall portion are laser welded.

[0027] According to the method for manufacturing an electronic component of the present disclosure, it is possible to manufacture an electronic component that can provide any one of the above-mentioned advantages (1) to (4). [Brief description of the drawings]

[0028] [Figure 1] FIG. 1 is a partially cutaway plan view of an electricity accumulation device according to an embodiment. [Diagram 2] 2A is a cross-sectional view taken along line IIA-IIA in FIG. 1, and FIG. 2B is an enlarged cross-sectional view of a portion B shown in FIG. 2A. [Diagram 3] FIG. 3 is a diagram showing the power storage device and the bus bar before connection. [Figure 4] FIG. 4 is a diagram showing the relationship between the weld length and the weld strength of a welded portion. [Diagram 5] FIG. 5A is a diagram showing the relationship between the diameter of the protruding bottom and the amount of expansion of the explosion-proof valve, and FIG. 5B is a diagram showing the relationship between the diameter of the protruding bottom and the central pressure of the explosion-proof valve. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] [One embodiment] An embodiment of the present disclosure will be described with reference to the reference numerals of the examples of the present disclosure. The electronic component (electricity storage device 2) according to the present disclosure includes a case 4, a first case surface portion (base portion 6-1), a second case surface portion (protruding bottom portion 6-2), a vertical wall portion 6-4, and an explosion-proof valve 10. The case 4 is a member for housing elements in the electronic component. The case 4 includes a first case surface portion and a second case surface portion. The second case surface portion is a range excluding the thickness of the vertical wall portion 6-4, and protrudes from the first case surface portion. The bottom surface portion of the case 4 includes the first case surface portion and the second case surface portion. Therefore, the first case surface portion (base portion 6-1) having the function of placing the terminal member (bus bar 12) and the second case surface portion (protruding bottom portion 6-2) having the function of concentrating the case deformation when the internal pressure rises are separated from the vertical wall portion 6-4.

[0030] Between the first case surface portion and the second case surface portion is included a vertical wall portion 6-4 that connects the first case surface portion and the second case surface portion. This vertical wall portion 6-4 is, for example, a wall portion of the case 4 that stands in a direction intersecting the first case surface portion and the second case surface portion, and is specified as an area excluding the first case surface portion and the second case surface portion (A in FIG. 2).

[0031] The second case surface is provided with an explosion-proof valve that opens when the internal pressure of the case increases, allowing gas to be released from the case. EXAMPLES

[0032] Fig. 1 shows an electricity storage device 2 according to an embodiment. The configuration shown in Fig. 1 is an example, and the present disclosure is not limited to such a configuration.

[0033] The electricity storage device 2 is an example of an electronic component of the present disclosure. The electricity storage device 2 includes, for example, a cylindrical case 4. A base portion 6-1 and a protruding bottom portion 6-2 are concentrically formed on the bottom of the case 4. The case 4 used in the electricity storage device 2 is not limited to a cylindrical shape. If the bottom of the case 4 is non-circular, such as a rectangular tube shape, the base portion 6-1 and the protruding bottom portion 6-2 on the bottom surface may have similar shapes.

[0034] The base portion 6-1 is an example of a first case surface portion of the present disclosure. In this example, the base portion 6-1 has a cylindrical side wall portion 6-3 on its periphery.

[0035] The protruding bottom portion 6-2 is an example of a second case surface portion of the present disclosure, and protrudes from the base bottom portion 6-1. The protruding bottom portion 6-2 includes an explosion-proof portion 8, and is provided with a cylindrical standing wall portion 6-4 that rises axially from the base bottom portion 6-1 on the periphery of the protruding bottom portion 6-2.

[0036] The explosion-proof section 8 is provided with an explosion-proof valve 10. This explosion-proof valve 10 is a Y-shaped groove formed radially at a specific angle θ1 (for example, θ1 = 120 degrees) from the center O of the bottom surface of the case 4. The explosion-proof valve 10 is a thin-walled groove, and opens when the internal pressure rise of the case 4 exceeds a threshold value. In other words, when the valve opens, a rupture occurs in the explosion-proof valve 10 at the thin-walled groove portion, and the broken pieces generated by this rupture are rolled up by the internal pressure rise, and the gas inside the case 4 is released from the ruptured portion.

[0037] If the length from the center of the explosion-proof valve 10 is L1 and the explosion-proof area of ​​the explosion-proof part 8 is S1, the explosion-proof area S1 can be expressed by formula 1. This explosion-proof area S1 represents the part that mainly performs the explosion-proof function.

[0038] S1 = π × (L1 / 2) 2 ...Formula 1

[0039] The standing wall portion 6-4 is an example of a standing wall portion of the present disclosure, and is a wall portion that connects the base portion 6-1 and the protruding bottom portion 6-2.

[0040] In this electricity storage device 2, if the diameter of the base portion 6-1 is D1 and the diameter of the vertical wall portion 6-4 is D2, the ratio of D2 to D1 (D2 / D1, where D2 includes the thickness t3 of the vertical wall portion 6-4) may be set in the range of, for example, 60% to 80%. If D1 in FIG. 1 is, for example, 25 mm, it is preferable that D2 is 15 to 20 mm. That is, A to D2 in FIG. 5 is preferably 20 mm or less. In this case, the connection stability between the bus bar 12 and the case 4 is good. B to D2 in FIG. 5 is preferably 15 mm or more. In this case, in consideration of the opening characteristics of the explosion-proof valve 10, if the stress of the case material (for example, aluminum) in the center of the explosion-proof valve 10 is low, the opening operation of the explosion-proof valve 10 may be reduced.

[0041] A bus bar 12 is connected to the vertical wall portion 6-4. The bus bar 12 is an example of a terminal member of the present disclosure. The bus bar 12 is welded to the vertical wall portion 6-4 at a welded portion 14, and laser welding is used for this welding, for example. The connection means may be a welding or fastening means other than laser welding.

[0042] If the width of the bus bar 12 is W1, the size of this width W1 can be expressed by Equation 2 if it is determined according to the angle θ1 set for the explosion-proof valve 10 and the diameter D2 of the vertical wall portion 6-4.

[0043] W1 = D2 × sin(θ1 / 2) < D2 ··· Equation 2

[0044] In this case, if the butt joint length of the two that brings the vertical wall portion 6-4 into contact with the bus bar 12 is L2, this butt joint length L2 can be expressed by Equation 3.

[0045] L2 = π × D2 × θ1 ÷ 360 ··· Equation 3

[0046] Here, if θ1 = 120 degrees, the butt joint length L2 can be expressed as follows from Equation 3.

[0047] L2 = π × D2 × 120 ÷ 360 = π × D2 ÷ 3 ··· Equation 4

[0048] Therefore, the width W1 shown in Equation 2 can satisfy the butt joint length L2 set in the range of θ1 = 120 degrees.

[0049] <Cross-sectional view taken along line IIA-IIA of FIG. 1> A in FIG. 2 shows a cross-sectional view taken along line IIA-IIA of FIG. 1 with a part of the power storage device 2 omitted.

[0050] The vertical wall portion 6-4 is a wall portion formed together with the protruding bottom portion 6-2 by molding the case member. This vertical wall portion 6-4 rises from the base portion 6-1 in the intersecting direction (for example, the vertical direction), is formed in the intersecting direction (for example, the vertical direction) with the protruding bottom portion 6-2, and a step is provided between the base portion 6-1 and the protruding bottom portion 6-2.

[0051] Elements (not shown) are housed in the case 4. The bus bar 12 constitutes the terminal portion on the cathode side, and a terminal portion 18 is arranged on the anode side on the sealing portion 16 side of the case 4.

[0052] If the diameter of the recess surrounded by the standing wall portion 6-4 is D3, the diameter D3 can be expressed by Equation 5 using the diameter D2 of the protruding bottom portion 6-2 and the thickness t3 of the standing wall portion 6-4.

[0053] D3 = D2 - t3 × 2 Equation 5

[0054] If the pressure-receiving area set within the recess surrounded by the standing wall portion 6-4 is denoted as S2, this pressure-receiving area S2 can be expressed by the following formula 6.

[0055] S2 = π × (D3 ÷ 2) 2 =π×{D2÷2-t3} 2 >S1...Formula 6

[0056] Therefore, the pressure inside the case 4 can be applied to the pressure-receiving area S2 surrounded by the standing wall portion 6-4.

[0057] <Welding section 14> At the weld 14, the bus bar 12 is welded to the vertical wall portion 6-4, and in this embodiment, the weld nugget 20 extends to the three components of the bus bar 12, the vertical wall portion 6-4, and the base portion 6-1, and the bus bar 12 is also welded to the base portion 6-1.

[0058] If the thickness of base portion 6-1 is t1, the thickness of protruding bottom portion 6-2 and explosion-proof portion 8 is t2, the thickness of vertical wall portion 6-4 is t3, the height of the spacing portion of vertical wall portion 6-4 is d (≧0), the height of vertical wall portion 6-4 is h, the thickness of explosion-proof valve 10 is t4, and the thickness of busbar 12 is t5, then the following size relationship exists.

[0059] t3>t1, t1=t3 or t1≒t3 t1, t3>t2>t4 h=t1+t2+d h>t5+t1, h=t5+t1 or h≒t5+t1 In this manner, the vertical wall portion 6-4 is set to a thickness equal to or greater than that of the base portion 6-1, and reinforces the surrounding area of ​​the protruding bottom portion 6-2 and the explosion-proof portion 8.

[0060] <Part B of A in Fig. 2> 2B shows an enlarged view of portion B in FIG. 2A. A weld nugget 20 is formed in the welded portion 14. The weld nugget 20 is a hardened portion of the molten metal of the busbar 12, the standing wall portion 6-4, and the base portion 6-1 that was generated by irradiating the butt portion of the busbar 12 and the standing wall portion 6-4 with a laser. In this example, the busbar 12 and the standing wall portion 6-4 that have been irradiated with the laser are welded, and the weld nugget 20 spreads to the base portion 6-1 and is welded to the base portion 6-1 as well as to the busbar 12 and the standing wall portion 6-4.

[0061] <Electricity storage device 2 and bus bar 12 before welding> 3 shows a part of the electricity storage device 2 and the busbar 12 before welding. The busbar 12 is formed with a fitting portion 22 for fitting into the standing wall portion 6-4 of the protruding bottom portion 6-2. The fitting portion 22 has an arcuate surface having the same curvature as the standing wall portion 6-4.

[0062] As shown by arrow m, fitting portion 22 of bus bar 12 is fitted into vertical wall portion 6-4 of case 4, and a laser is irradiated along the butted surface thereof to form welded portion 14 (FIG. 1).

[0063] If the length of the butt joint between the fitting portion 22 and the vertical wall portion 6-4 is L2, for example, the angle θ1=120 degrees, then this butt joint length L2 can be expressed by the above-mentioned formula 4.

[0064] If the contact area of ​​fitting portion 22 and standing wall portion 6-4 is S3, this contact area S3 can be expressed by Equation 7 using butt length L2 and thickness t5 of bus bar 12 when θ1=120 degrees.

[0065] S3=L2×t5=(π×D2÷3)×t5...Equation 7

[0066] Then, if the weld length of welded portion 14 is L3 (FIG. 1) and the angle of welded portion 14 is θ2, then this weld length L3 can be expressed by Equation 8.

[0067] L3 = π×D2×θ2÷360 < L2 ··· Equation 8

[0068] In the illustrated power storage device 2, the welding length L3 is set shorter than the butting length L2 (L2 > L3), and the butting length L2 is set longer than the welding length L3, but they may be the same (L2 = L3) or substantially the same (L2 ≒ L3).

[0069] <Manufacturing Process of Power Storage Device 2> The manufacturing process of the power storage device 2 including the bus bar 12 is an example of the manufacturing method of the electronic components of the present disclosure. This manufacturing process includes a forming process of the case 4, a forming process of the explosion-proof valve 10, and a connecting process of the bus bar 12.

[0070] The forming process of the case 4 includes a process of forming the case 4 with a case member made of a metal material such as aluminum, and a process of forming the base portion 6-1 and the protruding base portion 6-2 on the case 4. This process includes a process of forming the side wall portion 6-3 together with the base portion 6-1, and a process of forming the standing wall portion 6-4 between the base portion 6-1 and the protruding base portion 6-2.

[0071] The forming process of the explosion-proof valve 10 includes a process of forming the explosion-proof valve 10 with respect to the protruding base portion 6-2. The forming process of the explosion-proof valve 10 may be simultaneous with the forming process of the protruding base portion 6-2.

[0072] The connecting process of the bus bar 12 includes a process of welding the bus bar 12 to the standing wall portion 6-4. This welding process includes a process in which the welding nugget 20 growing on the welded portion 14 spreads to the base portion 6-1 by welding the bus bar 12 and the standing wall portion 6-4.

[0073] <Laser Welding> For laser welding, the laser may be irradiated along the butting surface of the fitting portion 22 of the bus bar 12 fitted to the standing wall portion 6-4 of the case 4. The laser irradiation may be performed within the range of the target welding length L3, and may be performed along the arc surfaces of the standing wall portion 6-4 and the bus bar 12.

[0074] <Effect of One Embodiment> According to this embodiment, any one of the following effects can be obtained.

[0075] (1) Separability of the base 6-1, protruding bottom 6-2 and vertical wall 6-4 A protruding bottom 6-2 is formed together with a base 6-1 on the bottom surface of the case 4, and the protruding bottom 6-2 is separated from the base 6-1 by a standing wall 6-4, which enhances the separability of the base 6-1, the protruding bottom 6-2, and the standing wall 6-4. The welds 14 connecting the standing wall 6-4 and the busbar 12 can be concentrated on the standing wall 6-4 side, which allows the protruding bottom 6-2 and the welds 14 to be separated.

[0076] The thickness of the case member of the vertical wall portion 6-4 can be set thicker than that of the explosion-proof portion 8, and the connection between the explosion-proof portion 8 and the bus bar 12 can be separated.

[0077] (2) Strengthening the bottom of Case 4 The bottom surface of the case 4 has a protruding bottom portion 6-2 protruding from a base portion 6-1 together with an upright wall portion 6-4, which enables the bottom surface of the case 4 to be strengthened.

[0078] (3) Protection of the protruding bottom 6-2 The protruding bottom 6-2 is reinforced by the vertical wall 6-4 rising from the base 6-1, which enhances the protective properties of the protruding bottom 6-2. The protruding bottom 6-2 is provided with an explosion-proof section 8 including an explosion-proof valve 10, which can protect the protruding bottom 6-2.

[0079] (4) Strengthening explosion-proof function The explosion-proof section 8 including the explosion-proof valve 10 formed on the protruding bottom portion 6-2 is protected around its periphery by the annular vertical wall portion 6-4, thereby protecting the explosion-proof function of the explosion-proof section 8 including the explosion-proof valve 10 and enhancing the protective function.

[0080] (5) Deformation prevention of the case 4 except for the explosion-proof part 8 The protruding bottom 6-2 protrudes outward from the bottom surface of the case 4, and the internal pressure rise of the case 4 can be concentrated on the explosion-proof section 8, improving the explosion-proof function. Therefore, the internal pressure rise of the case 4 can be guided to the protruding bottom 6-2 side and acted on the explosion-proof section 8 side, preventing deformation of the case 4 side other than the explosion-proof section 8.

[0081] (6) Strengthening of vertical wall section 6-4 Bus bars 12 are connected to the vertical wall portions 6-4 by, for example, welding, and the connection with the bus bars 12 makes it possible to strengthen the vertical wall portions 6-4.

[0082] (7) Positioning of busbar 12 By fitting fitting portion 22 into standing wall portion 6-4, busbar 12 can be easily positioned with respect to standing wall portion 6-4. In other words, the center line of busbar 12 can be aligned with the center of standing wall portion 6-4, the circumferential position of standing wall portion 6-4 of busbar 12 can be determined, and the positioning accuracy of busbar 12 with respect to protruding bottom portion 6-2 can be improved.

[0083] (8) Strengthening the connection between the vertical wall section 6-4 and the bus bar 12 The weld nugget 20 can be grown in the same direction as the vertical wall portion 6-4, which strengthens the connection between the vertical wall portion 6-4 and the busbar 12 while avoiding the effect of welding on the explosion-proof portion 8 at the protruding bottom portion 6-2. The vertical wall portion 6-4 and the busbar 12 can be connected by butt welding, and the busbar 12 and the base portion 6-1 can be connected by lap welding, which strengthens the connection of the busbar 12 to the case 4.

[0084] (9) Simplification of welding between the vertical wall portion 6-4 and the bus bar 12 The fitting portion 22 of the bus bar 12 is fitted into the vertical wall portion 6-4 and a laser is irradiated along this fitting portion 22, which facilitates the welding work and increases the reliability of the connection between the vertical wall portion 6-4 and the bus bar 12.

[0085] (10) Welding options for busbar 12 case 4 The weld nugget 20 formed by welding the busbar 12 can be grown to the vertical wall portion 6-4, and further to the vertical wall portion 6-4 and the base portion 6-1. Therefore, welding of the busbar 12 to the case 4 can be performed by at least welding the busbar 12 to the vertical wall portion 6-4, and welding the busbar 12 to the vertical wall portion 6-4 and the base portion 6-1. Preferably, welding of the busbar 12 to the vertical wall portion 6-4 is sufficient, and more preferably welding of the busbar 12 to the vertical wall portion 6-4 and the base portion 6-1 is sufficient. If the thickness t1 of the base portion 6-1 is set to be equal to the thickness t3 of the vertical wall portion 6-4, perforation due to welding can be avoided.

[0086] (11) Support of busbar 12 by base 6-1 The terminal member can be placed on the first case surface portion and connected to the upright wall portion, and the terminal member can be supported by the first case surface portion, thereby enhancing the stability of the terminal member.

[0087] (12) Release of expanding air during laser welding Providing a gap between bus bar 12 and base portion 6-1 allows the expanded air to be released when bus bar 12 and standing wall portion 6-4 are laser welded together.

[0088] <Relationship between weld length L3 and weld strength> FIG. 4 is a diagram showing the relationship between the weld length L3 and the weld strength.

[0089] The relationship between the weld length L3 and the weld strength was confirmed by an experiment. In this experiment, the width W1 of the busbar 12 was arbitrarily changed, and the weld strength of the welded portion 14 was measured when the weld length L3 was set to 4 to 20 [mm].

[0090] According to this experiment, as shown in Figure 4, for a weld length L3: L3 = 4 to 20 [mm], a weld strength of 500 [N] was obtained at 12.5 [mm]. The experimental results showed that higher weld strength was obtained as the weld length L3 increased. The experimental results confirmed that high weld strength can be obtained by setting L3 = 12.5 [mm] or more.

[0091] <Relationship between diameter D2 of protruding bottom 6-2 and swelling amount of explosion-proof valve 10> FIG. 5A is a diagram showing the relationship between the diameter D2 of the protruding bottom portion 6-2 and the amount of expansion of the explosion-proof valve 10. FIG.

[0092] The relationship between the diameter D2 of the protruding bottom 6-2 and the amount of expansion of the explosion-proof valve 10 was confirmed by an experiment. In this experiment, the amount of expansion of the explosion-proof valve 10 was measured when 1.8 [MPa] was applied to the case 4 in which the diameter D2 of the protruding bottom 6-2 was set to D2 = 12 to 24 [mm].

[0093] According to this experiment, as shown in Fig. 5A, the expansion amount [mm] of the explosion-proof valve 10 was measured for diameter D2 of the protruding bottom 6-2 of D2 = 12 to 24 [mm]. From this experimental result, the expansion amount [mm] of the explosion-proof valve 10 was obtained as a quadratic function as the diameter D2 of the protruding bottom 6-2 increases. From this experimental result, it was confirmed that the expansion amount [mm] of the explosion-proof valve 10 is within the allowable value if the diameter D2 of the protruding bottom 6-2 is 20 [mm] or less at the assumed case internal pressure = 1.8 [MPa].

[0094] <Relationship between the diameter D2 of the protruding bottom 6-2 and the central pressure of the explosion-proof valve 10> FIG. 5B is a diagram showing the relationship between the diameter D2 of the protruding bottom portion 6-2 and the central pressure of the explosion-proof valve 10.

[0095] The relationship between the diameter D2 of the protruding bottom 6-2 and the pressure at the center of the explosion-proof valve 10 was confirmed by an experiment. In this experiment, the pressure at the center of the explosion-proof valve 10 was measured when 1.8 MPa was applied to the case 4 in which the diameter D2 of the protruding bottom 6-2 was set to D2 = 12 to 18 mm.

[0096] According to this experiment, as shown in FIG. 5B, the stress of the central member (aluminum) of the explosion-proof valve 10 was measured for diameter D2 of the protruding bottom 6-2 of D2 = 12 to 18 [mm]. From this experimental result, it was confirmed that the central pressure of the explosion-proof valve 10 increases in a quadratic function manner as the diameter D2 of the protruding bottom 6-2 increases. From this experimental result, it was confirmed that the central pressure required to operate the explosion-proof valve 10 is 15 [mm] or more for the diameter D2 of the protruding bottom 6-2 at the assumed case internal pressure = 1.8 [MPa].

[0097] Other Embodiments (1) Width W1 of busbar 12 In one embodiment, the width W1 of the busbar 12 is set to a width corresponding to the angle θ of the explosion-proof valve 10, but it may be set regardless of the angle θ of the explosion-proof valve 10.

[0098] The width W1 of the busbar 12 may be set to any desired width regardless of the diameter D2 of the protruding bottom portion 6-2 and the standing wall portion 6-4.

[0099] (2) Shape of busbar 12 In one embodiment, the bus bar 12 has a flat plate shape, but may have an L-shaped bent shape.

[0100] The fitting portion 22 of the busbar 12 is formed of an arcuate surface portion that matches the peripheral surface of the standing wall portion 6-4, but may be cylindrical or ring-shaped to be fitted into the standing wall portion 6-4.

[0101] (3) Shape of side wall portion 6-3 Although the side wall portion 6-3 is flush with the bottom surface of the protruding bottom portion 6-2 or the bus bar 12, the side wall portion 6-3 may protrude from the surface of the protruding bottom portion 6-2 or the bus bar 12.

[0102] (4) Shape of explosion-proof valve 10 In one embodiment, the grooves are formed in a Y shape, but any shape such as a - shape, an X shape, a + shape, or a shape in which a plurality of grooves are formed radially from the center may be used.

[0103] (5) Form of electronic component such as power storage device 2 In the embodiment, an axial type is illustrated as the electricity storage device 2, but the present disclosure may also be applied to electronic components such as a radial type electricity storage device.

[0104] As described above, the most preferred embodiment of the electricity storage device of the present disclosure has been described, but the present disclosure is not limited to the above description. Based on the gist of the present disclosure described in the claims or disclosed in the specification, those skilled in the art can make various modifications and changes. It goes without saying that such modifications and changes are included in the scope of the present disclosure. [Industrial Applicability]

[0105] The electronic component and manufacturing method thereof disclosed herein are useful in that they include a vertical wall portion 6-4 connected to a base portion 6-1, which is a first case surface portion, and a protruding bottom portion 6-2, which is a second case surface portion, and a bus bar 12, which is a terminal member, can be connected to this vertical wall portion 6-4, thereby improving the explosion-proof function of the explosion-proof valve, connectivity with the terminal member, and the reliability of the explosion-proof function. [Explanation of symbols]

[0106] 2. Energy storage devices 4 Cases 6-1 Base 6-2 Protruding bottom 6-3 Side wall 6-4 Vertical wall 8 Explosion-proof section 10 Explosion-proof valve 12 Busbar 14 Welding 16 Sealing part 18 Terminal section 20 Welding Nugget 22 Fitting part

Claims

1. A case for storing the element; a first case surface portion set in the case; a second case surface portion protruding from the first case surface portion; a vertical wall portion connecting the first case surface portion and the second case surface portion; an explosion-proof valve provided on the second case surface portion, which opens when the internal pressure of the case increases and releases gas from the case; Including, electronic components.

2. 2. The electronic component according to claim 1, further comprising a terminal member connected to said case, said terminal member being welded to at least said upright wall portion.

3. The electronic component according to claim 2 , wherein the terminal member is further welded to the first case surface portion.

4. The electronic component according to claim 1 , wherein the vertical wall portion or the first case surface portion is thicker than the second case surface portion.

5. 3. The electronic component according to claim 2, wherein a peripheral edge of the second case surface is reinforced by the upright wall and further reinforced by welded portions to the terminal members.

6. 3. The electronic component according to claim 2, wherein the abutment length between the terminal member and the standing wall portion is at least one-fourth or more than one-fourth of the circumferential length of the standing wall portion.

7. a step of forming a case using a case member, and forming a first case surface portion and a second case surface portion on the case, as well as a standing wall portion connecting the first case surface portion and the second case surface portion; forming an explosion-proof valve on the second case surface; A method for manufacturing an electronic component, comprising:

8. The method for manufacturing an electronic component according to claim 7 , further comprising the step of welding a terminal member to at least the vertical wall portion, or to the vertical wall portion and the first case surface portion.

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