Electrical device and method for manufacturing same

Abstract

The present invention suppresses springback with a simple configuration. The electrical device is provided with: a lead plate (30) having a bent piece (32) in which a part of the lead plate (30) is bent along a bending line (31); a circuit board (3) electrically connected to the bent piece (32) of the lead plate (30); and a holder part (20) that holds the lead plate (30). The holder part (20) is provided with a holding part (26) for locking a part of the upper surface of the bent piece (32). The holding part (26) is configured to abut against a part of the upper surface of the bent piece (32) and hold the bent piece (32) in a posture opposite to the direction of resilience generated by bending the bent piece (32) of the lead plate (30) along the bending line (31). The circuit board (3) is provided with a connection region (4) that is electrically connected to the lead plate (30). The bending sheet (32) is electrically connected to the connection region (4).

Description

Technical Field

[0001] The present disclosure relates to an electrical device and a method of manufacturing the same. Background Art

[0002] In an electrical device such as a battery pack, a lead plate is fixed by soldering, welding, etc. in order to obtain electrical connection during the manufacturing process (e.g., Patent Document 1). In such a manufacturing process, due to the constraints of the structure of each component, the assembly method, etc., the lead plate is sometimes bent during the assembly process and then welded to the circuit board or soldered.

[0003] Here, when the lead plate is bent to a specific position, springback occurs, which is the inevitable return of the lead plate to its original shape. When springback occurs, the lead plate will not be closely attached to the circuit board and will separate, which may cause poor welding and soldering, resulting in poor electrical connection such as poor contact. Therefore, in order to reliably fix the lead plate at the bent position and stably perform welding and soldering, it is necessary to provide a structure to suppress springback and perform soldering in a completely fixed state.

[0004] As such a structure for suppressing springback, for example, a clamp or a screw fastener is used to fix the lead plate to the circuit board by a fixing mechanism such as a screw. However, in such a structure, there are the following problems: the number of components for fixing the lead plate to the circuit board increases, resulting in an increase in cost. In addition, there is also a problem that the degree of freedom in designing the fixing mechanism is small.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Publication No. 2014-514722 Summary of the invention

[0008] Problems to be solved by the invention

[0009] One of the objects of the present disclosure is to provide an electric device capable of suppressing springback with a simple structure and a method for manufacturing the same.

[0010] Means for solving problems

[0011] An electrical device according to one embodiment of the present invention comprises: a lead plate, wherein the lead plate has a bent piece obtained by bending a portion of the lead plate along a bending line; a circuit substrate, wherein the circuit substrate is electrically connected to the bent piece of the lead plate; and a holder portion, wherein the holder portion holds the lead plate, the holder portion is formed with a holding portion for locking a portion of the upper surface of the bent piece, the holding portion being configured to hold the lead plate in contact with a portion of the upper surface of the bent piece in a posture opposite to a direction of rebound caused by bending the bent piece of the lead plate along the bending line, the circuit substrate having a connection area electrically connected to the lead plate, and the bent piece is electrically connected to the connection area.

[0012] In addition, in another embodiment of the present invention, the manufacturing method of an electrical device comprises a lead plate, a circuit substrate electrically connected to the lead plate, and a retainer portion for retaining the lead plate. The manufacturing method of the electrical device comprises: a step of bending the lead plate, inserting a retaining portion formed on the electrical device into a window portion opened in the lead plate, and retaining the lead plate by abutting a portion of the periphery of the window portion with the retaining portion; and a step of laser welding the lead plate to connect it to the circuit substrate while the lead plate is retained by the retaining portion.

[0013] Effects of the Invention

[0014] According to the electric device and the method for manufacturing the electric device of one aspect of the present invention, the springback generated when the lead plate is bent can be suppressed by the holding portion, thereby improving the stability of the lead plate when being fixed. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a perspective view of the battery pack according to the first embodiment.

[0016] Figure 2 yes Figure 1 An exploded perspective view of the battery pack.

[0017] Figure 3 yes Figure 2 An exploded perspective view of a battery module.

[0018] Figure 4 yes Figure 2 An enlarged view of the main parts of the battery module.

[0019] Figure 5 Yes means Figure 4 An enlarged view of the main parts of the battery module before assembly.

[0020] Figure 6 Observe from different angles Figure 5 An enlarged stereoscopic image of a battery module.

[0021] Figure 7 It means that Figure 6 An enlarged stereoscopic view of the lead plate of a battery module after being bent.

[0022] Figure 8 yes Figure 7 sectional view of .

[0023] Fig. 9A is an enlarged cross-sectional view of a main part showing a lead plate fixing structure of a battery pack according to a second embodiment, Fig. 9B yes Fig. 9A A top view of the lead plate fixing structure.

[0024] Fig. 10A is an enlarged cross-sectional view of a main part showing a lead plate fixing structure of a battery pack according to a third embodiment, Fig. 10B yes Fig. 10A A top view of the lead plate fixing structure.

[0025] Fig.11A is an enlarged cross-sectional view of a main part showing a lead plate fixing structure of a battery pack according to a fourth embodiment, Fig. 11B yes Fig.11A A top view of the lead plate fixing structure. DETAILED DESCRIPTION

[0026] The aspects of the present invention can be identified by the following configurations and features.

[0027] In another embodiment of the present invention, the lead plate is formed with a through window in the above embodiment, and the holding portion is configured to hold the lead plate by contacting a portion of the periphery of the window in a posture opposite to the direction in which the bending piece rebounds when the holding portion is inserted through the window of the lead plate. According to the above configuration, by inserting the holding portion through the window and contacting the upper surface of the bending piece, the rebound of the lead plate can be suppressed and the stability of the lead plate when it is fixed can be improved.

[0028] Furthermore, in another embodiment of the electrical device of the present invention, in any of the above embodiments, the lead plate has a laser welding area on a portion of the lower surface of the bending piece for laser welding with the connection area. According to the above configuration, the following advantages can be obtained: during laser welding, the retaining portion can be used to suppress the generation of a gap between the lead plate and the connection area, thereby improving the reliability of laser welding.

[0029] Furthermore, in an electric device according to another aspect of the present invention, in any of the above aspects, the holding portion is formed in a hook shape.

[0030] In addition, in the electrical device of other modes of the present invention, in any of the above modes, the lead plate is formed with a leaf spring at the end edge of the window portion and at a position opposite to the holding portion. According to the above configuration, the following advantages can be obtained: the pressing force of the leaf spring can be used to increase the reaction force (rebound force) of the contact surface with the holding portion, and the lead plate can be pressed toward the circuit substrate side more reliably to improve reliability.

[0031] In addition, in another embodiment of the present invention, in any of the above embodiments, the holding portion is formed into a columnar shape, the window portion of the lead plate is formed into a hole shape for inserting the columnar holding portion, and the electrical device is configured such that, when the columnar holding portion is inserted into the hole-shaped window portion, the front end of the columnar holding portion is flattened to press the periphery of the hole-shaped window portion. According to the above configuration, the lead plate can be pressed by a simple configuration of flattening the front end of the columnar holding portion.

[0032] In addition, in other forms of electrical equipment of the present invention, in any of the above-mentioned forms, the retaining portion is formed into a cylindrical shape, and the lead plate forms the window portion into a circular shape for inserting the cylindrical retaining portion, and the electrical equipment is configured so that when the cylindrical retaining portion is inserted into the circular window portion, the front end of the cylindrical retaining portion is flattened to press the surrounding area of ​​the circular window portion.

[0033] Furthermore, in an electric device according to another aspect of the present invention, in any of the above aspects, the holding portion and the holder portion are integrally formed.

[0034] In addition, in another embodiment of the present invention, the electrical device further comprises one or more secondary battery cells connected to the circuit substrate via the lead plate in any of the above embodiments, the retainer portion is formed with the retainer portion in the area around the circuit substrate, and the electrical device is a battery pack. According to the above configuration, by providing the retainer portion with the retainer portion, the lead plate can be stably retained and connected to the circuit substrate without the need to prepare a fixing mechanism for retaining the lead plate separately.

[0035] In addition, in other forms of electrical equipment of the present invention, in any of the above forms, when viewed from above, the lead plate has step portions formed on its side surfaces, the retaining portions are respectively arranged on the step portions of the lead plate, and each retaining portion is provided with a locking portion for locking the upper surface of the step portion.

[0036] In addition, an electrical device of another embodiment of the present invention comprises: a lead plate, a portion of which is bent; a circuit substrate, which is electrically connected to the lead plate; and a retainer portion, which retains the lead plate, the lead plate having a through window portion formed therein, the retainer portion having a retaining portion, which, when inserted through the window portion of the lead plate, abuts against a portion of the periphery of the window portion for retaining the lead plate in a posture opposite to a direction in which a rebound is generated relative to the bending of the lead plate.

[0037] Hereinafter, the embodiments of the present invention will be described based on the accompanying drawings. However, the embodiments shown below are examples for concretizing the technical ideas of the present invention, and the present invention is not specific to the following contents. In addition, this specification will never specify the components shown in the claims as the components of the embodiments. In particular, the size, material, shape, relative configuration, etc. of the components recorded in the embodiments are not intended to limit the scope of the present invention to only this, as long as there is no particularly determined record, but are just simple illustrative examples. In addition, the size, positional relationship, etc. of the components shown in the drawings are sometimes exaggerated for the purpose of clear description. Moreover, in the following description, with respect to the same name, figure mark, representing the same or homogeneous components, detailed description is appropriately omitted. Moreover, the elements constituting the present invention can be a method in which the same component constitutes multiple elements and one component is used as multiple elements, or conversely, multiple components can share the function of realizing one component.

[0038] The electrical device of the present invention can utilize an electrical device having a circuit substrate to which a lead plate is fixed and a retainer portion for retaining the circuit substrate. Examples of electrical devices include battery packs having one or more secondary battery cells, mobile phones, smart phones, cameras, wireless devices, and other battery-driven devices having secondary battery cells built in. Here, as an example of electrical devices, an example of application to a battery pack is described.

[0039] The battery pack can be used as a driving power source for auxiliary bicycles, a driving power source for electric carts (carts) for delivery or golf courses, electric scooters and other mobile devices, etc. In addition, it can also be used as a driving power source for vehicles such as construction machinery, hybrid vehicles, and electric vehicles. Moreover, it can also be used as a power source for portable electrical equipment such as electric cleaners, sweeping robots, power tools, and wireless devices. Alternatively, it can also be used as a backup power source for servers, a power supply device for home use, office use, and factory use in fixed power storage applications. Below, as one embodiment of the present invention, a battery pack used as a driving power source for an auxiliary bicycle is cited as an example for explanation.

[0040] [Implementation Method 1]

[0041] Figure 1 to Figure 31 and 2 show a battery pack 100 according to Embodiment 1 of the present invention. In these drawings, Figure 1 A perspective view showing a battery pack 100 according to Embodiment 1, Figure 2 express Figure 1 An exploded perspective view of a battery pack 100 , Figure 3 express Figure 2 1 is an exploded perspective view of a battery module 2. The battery pack 100 shown in these figures includes an outer casing 10, a battery module 2, and a circuit board 3. The battery module 2 includes one or more secondary battery cells 1 and a holder 20 that holds the secondary battery cells 1. In addition, each secondary battery cell 1 is connected to the circuit board 3 via a lead plate 30.

[0042] (External casing 10)

[0043] The outer casing 10 accommodates one or more secondary battery cells 1 and a holder 20. Figure 1 , Figure 2 As shown in the figures, the outer shell 10 has a box-like appearance. The outer shell 10 is formed into a cylindrical shape with the ends in the longitudinal direction opened. The open ends are closed by covers 11 and 12, respectively. In addition, the outer shell is not limited to this structure, and can be divided into an upper shell and a lower shell, for example. The outer shell 10 can be made of a metal with excellent rigidity and heat dissipation, or a lightweight resin with excellent insulation, such as polycarbonate, PC-ABS alloy, etc. In addition, as Figure 2 As shown, a storage space for storing the battery module 2 is provided inside the outer casing 10 .

[0044] (Secondary battery cell 1)

[0045] The one or more secondary battery cells 1 can use a secondary battery cell whose outer can is cylindrical or rectangular. Figure 2 , Figure 3 In the example of , a cylindrical secondary battery cell is used. Each secondary battery cell 1 has a positive and negative electrode. The positive and negative electrodes are preferably provided on each end surface of the secondary battery cell 1. Such a secondary battery cell 1 can appropriately utilize a known secondary battery such as a lithium ion secondary battery, a nickel-hydrogen battery, or a nickel-cadmium battery.

[0046] (Retainer portion 20)

[0047] The plurality of secondary battery cells 1 are housed in the holder portion 20. The holder portion 20 is provided with a plurality of housing tubes 22 that house the secondary battery cells 1 independently. Figure 3 In the example of FIG. 1 , the holder portion 20 is divided into two in the horizontal direction, and the cylindrical secondary battery cell 1 in the horizontal position is accommodated in the storage tubes 22 of the split cases 21A and 21B from both sides. Such a holder portion 20 may be made of a resin such as polycarbonate having excellent insulation properties.

[0048] (Lead plate 30)

[0049] A lead plate 30 is disposed on the side surface of the holder portion 20. The lead plate 30 connects the electrodes at the end surfaces of the secondary battery cells 1 to each other, and connects the plurality of secondary battery cells 1 in series or in parallel. Figure 2 , Figure 3 In the example of , 10 secondary battery cells 1 are connected in series and 4 in parallel. The number, arrangement, and number of series and parallel connections of the secondary battery cells are not limited to this example, and any number and arrangement may be appropriately adopted.

[0050] The lead plate 30 is made of a metal plate having excellent electrical conductivity, such as nickel or aluminum. Insulating plates 40 are disposed on the end surfaces of the lead plate 30. The insulating plates 40 are made of a material having excellent insulating properties, such as paper or polycarbonate.

[0051] In addition, if Figure 3 As shown in the exploded perspective view of FIG. 1 , the circuit substrate 3 is placed on the upper surface of the holder portion 20. The holder portion 20 holds the secondary battery cell 1 and the circuit substrate 3. The battery module 2 is connected to the circuit substrate 3 via the lead plate 30. On the upper surface of the holder portion 20 constituting the battery module 2, a placement surface 24 on which the circuit substrate 3 is placed is formed.

[0052] (Circuit board 3)

[0053] The circuit board 3 is mounted with a charge and discharge circuit for charging and discharging the secondary battery cell 1, a protection circuit for monitoring the voltage and temperature of the secondary battery cell 1 and interrupting the current in the event of an abnormality, etc. The circuit board 3 is made of a glass epoxy substrate or the like.

[0054] (Bending piece 32)

[0055] The lead plate 30 has a bent piece 32 in which a portion of the lead plate 30 is bent along a bending line 31. Figure 3 , Figure 4 In the example of FIG. 1 , a bent piece 32 is provided on the upper portion of the lead plate 30 . The lead plate 30 is electrically connected to the circuit board 3 by the bent piece 32 .

[0056] (Holding section 26)

[0057] The retainer portion 20 is formed with a retaining portion 26 that locks a portion of the upper surface of the bent piece 32. The retaining portion 26 is configured to abut against a portion of the upper surface of the bent piece 32 in a posture opposite to the direction of the springback generated when the bent piece 32 of the lead plate 30 is bent along the bending line 31 to retain the lead plate 30. With such a configuration, the retaining portion 26 can suppress the springback generated when the lead plate 30 is bent, and improve the stability of the lead plate 30 when it is fixed. Based on Figures 4 to 8In these figures, Figure 4 yes Figure 2 An enlarged view of the main parts of the battery module 2, Figure 5 Yes means Figure 4 An enlarged view of the main parts of the battery module 2 before assembly, Figure 6 Observe from different angles Figure 5 An enlarged perspective view of the battery module 2, Figure 7 It means that Figure 6 An enlarged perspective view of a battery module 2 in which the lead plate 30 is bent. Figure 8 express Figure 7 sectional view of .

[0058] When the upper end of the lead plate 30 fixed to the end surface of the secondary battery cell 1 is fixed to the connection area 4 provided on the circuit substrate 3, first, Figure 5 As shown in FIG. 1 , the circuit board 3 is placed on the placement surface 24 of the holder portion 20 without bending the upper end of the lead plate 30. This is because if the lead plate 30 is bent in advance, it will hinder the placement of the circuit board 3. Then, as shown in FIG. Figure 4 As shown, the bent piece 32 at the upper end of the lead plate 30 is bent and welded in a state of contact with the connection area 4 of the circuit board 3. In recent years, laser welding is preferably used for connecting the lead plate 30 from the viewpoint of solderless (Japanese: Handa Leisu).

[0059] However, even if the metal lead plate 30 is Figure 6 The bent piece 32 is in an upright state. Figure 7 Such bending will also cause springback to return to the original state and cause the bent piece 32 to float, resulting in a possibility of a gap between the lead plate 30 and the connection area 4. If a gap is generated, the reliability of laser welding will be impaired. Therefore, in the past, in order to press the bent piece 32 to the connection area 4, a fixing mechanism such as a screw is required, which has the problem of complicating the structure and taking time.

[0060] In contrast, in the battery pack 100 of the present embodiment, the holding mechanism for preventing the bending piece 32 from floating is added to the holder portion 20, thereby eliminating the need for preparing a separate fixing mechanism. Figure 6 , Figure 7 , Figure 8 As shown in FIGS. 1 and 1B , a holding portion 26 is formed at an end portion of the holder portion 20 and in a region that holds the periphery of the circuit board 3 .

[0061] (Window 34)

[0062] In this example, a window portion 34 is formed to penetrate the lead plate 30. In addition, the holding portion 26 is configured to hold the lead plate 30 by contacting a portion of the periphery of the window portion 34 in a posture opposite to the direction in which the bent piece 32 rebounds while being inserted through the window portion 34 of the lead plate 30. According to such a configuration, by inserting the holding portion 26 through the window portion 34 and contacting the upper surface of the bent piece 32, the rebound of the lead plate 30 can be suppressed and the stability of the lead plate 30 when being fixed can be improved.

[0063] The holding portion 26 is provided on the mounting surface 24 of the holder portion 20 and along each side surface in the longitudinal direction of the circuit board 3 for each lead plate 30. Figures 4 to 8 In the example of FIG. 2 , the holder portion 20 has a wall portion 25 formed on both sides of the mounting surface 24 in a dam-like manner covering the end surface of the circuit board 3 . The holding portion 26 is formed integrally on the upper surface of the wall portion 25 .

[0064] In addition, the holding portion 26 is formed in a hook shape. The hook shape has an inclined surface 27 formed on the upper surface. Figure 8 As shown in the figure, it is easy to pass through the window 34 of the bent piece 32 from above the holding portion 26, and after the hook-shaped portion passes through the window 34, the bottom surface of the hook-shaped portion abuts against the upper surface of the peripheral edge of the window 34 to hold it. With such a structure, the holding portion 26 can easily pass through the window 34 and is not easy to fall off after passing through it temporarily.

[0065] exist Figure 5 to Figure 7 In the example of FIG. 1 , the window portion 34 opens so as to overlap with the second bending line 35 of the lead plate 30 bent according to the outer shape of the holder portion 20. The window portion 34 opens at a position where the holder portion 26 can be inserted when the bending piece 32 is bent.

[0066] The lead plate 30 and the connection area 4 are laser welded in a state of being in contact with each other by the holding portion 26. Figure 8 As shown, a laser welding area 33 for laser welding with the connection area 4 is provided on a part of the lower surface of the bent piece 32 of the lead plate 30. By suppressing the generation of a gap between the lead plate 30 and the connection area 4 by the holding portion 26, the reliability of laser welding can be improved.

[0067] (Manufacturing method of electric device)

[0068] Here, a method for manufacturing an electric device having such a lead plate 30, a circuit board 3, and a holder portion 20 is described. First, the lead plate 30 is bent, and the holder portion 26 formed in the electric device is inserted into the window portion 34 opened in the lead plate 30, and the holder portion 26 abuts against a part of the periphery of the window portion 34 to hold the lead plate 30. Then, while the lead plate 30 is held by the holder portion 26, the lead plate 30 is connected to the circuit board 3 by laser welding. In this way, the holder portion 26 can suppress the springback generated when the lead plate 30 is bent, and the stability during fixing can be improved.

[0069] [Implementation Method 2]

[0070] The structure of pressing the bent piece 32 toward the connection area 4 by the holding portion 26 is not limited to the above structure, and other structures can be appropriately adopted. For example, a structure that increases the pressing force can also be added on the window side. Fig. 9A , Fig. 9B Such an example is shown in FIG. 2 as a battery pack 200 according to Embodiment 2. In these drawings, the same reference numerals are given to the same components as those in Embodiment 1 described above, and detailed descriptions thereof are appropriately omitted.

[0071] like Fig. 9A A cross-sectional view of Fig. 9B As shown in the top view of the embodiment 2, the battery pack 200 of the second embodiment has a leaf spring 37 formed at the edge of the window portion 34B of the bent piece 32B so as to face the holding portion 26B. The leaf spring 37 is formed by forming a pair of sides (at the left and right sides) of the rectangular window portion 34 that are not engaged with the holding portion 26. Fig. 9B On the other hand, the holding portion 26B provided in the holder portion 20B is formed in a claw shape similarly to the first embodiment.

[0072] In addition, a protrusion 39 that protrudes relative to the holding portion 26 may be provided at the end edge of the leaf spring 37. Fig. 9A In the example shown in the cross-sectional view of FIG, the edge of the leaf spring 37 engaged with the holding portion 26 is folded in a mountain shape to form a protrusion 39. By adding such a protrusion 39, it is possible to avoid the generation of a gap or floating between the window portion 34 and the holding portion 26, and the bent piece 32 can be more reliably abutted against the connection area 4 to improve reliability. In addition, by utilizing the pressing force of the leaf spring 37 to increase the reaction force of the contact surface in contact with the holding portion 26, it is also possible to more reliably press the lead plate 30 toward the circuit substrate 3 side.

[0073] [Implementation method 3]

[0074] In addition, the retaining portion is not limited to a hook shape, and may be formed in a pin shape. For example, the retaining portion may be set in a columnar shape, and the window portion may be formed in a hole shape into which the columnar retaining portion can be inserted. And, when the columnar retaining portion is inserted into the hole-shaped window portion, the front end of the columnar retaining portion is flattened to press the periphery of the hole-shaped window portion. Even with such a simple structure as flattening the front end of the columnar retaining portion, it is possible to press the lead plate. Fig. 10A , Fig. 10B 2 is a diagram showing such an example as a battery pack 300 according to Embodiment 3. In these drawings as well, the same reference numerals are given to the same components as those in Embodiment 1 and the like, and detailed descriptions thereof are omitted as appropriate.

[0075] exist Fig. 10A In the example, the retaining portion 26C provided in the retainer portion 20C is set to a cylindrical shape, and the window portion 34C opened in the bending piece 32C is set to a circular shape with an inner diameter slightly larger than the outer diameter of the cylindrical retaining portion 26C. When the circular window portion 34C is inserted into the cylindrical retaining portion 26C, the front end of the retaining portion 26C is pressed by a heated iron plate to flatten it and expand it into a flange shape 26C1. As a result, the flange shape 26C1 formed on the upper surface of the retaining portion 26 presses the periphery of the circular window portion 34C, so that the bending piece 32C can abut against the connection area 4.

[0076] In the above example, one holding portion is provided for each lead plate and pressed against the connection region. However, the present invention is not limited to this configuration, and a plurality of holding portions may be provided for each lead portion and pressed against the connection region.

[0077] Furthermore, in the above example, the following configuration is described: by providing the window portion 34 in the bending piece 32 and locking or engaging the holding portion 26 with the window portion 34, the bending piece 32 is pressed against the connection area 4. However, the present invention is not limited to this configuration, and the bending piece may be held by locking or engaging the holding portion without providing the window portion.

[0078] [Implementation Method 4]

[0079] As an example of a structure in which the bent piece is pressed against the connection area without providing a window portion, Fig.11A The cross-sectional view and Fig. 11BThe battery pack 400 of the fourth embodiment is shown in the top view. In these figures as well, the same reference numerals are given to the same components as those of the first embodiment described above, and detailed descriptions are omitted as appropriate. In this example, when viewed from above, step portions 32D1 are respectively formed on the side surfaces of the bending piece 32D of the lead plate. In addition, the retaining portions 26 are respectively provided on the retainer portion 20 on both sides of the side surface of the bending piece 32D so as to face the step portions 32D1. Each retaining portion 26 is provided with a locking portion 26D1 for locking the upper surface of the step portion 32D1. Thus, by locking the left and right step portions 32D1 of the bending piece 32D using each retaining portion 26, the bending piece 32D can be brought into contact with the connection area 4. According to this configuration, it is not necessary to form a window portion in the bending piece 32D, so that the area of ​​the bending piece 32D can be increased and the resistance can be reduced.

[0080] Furthermore, in the above configuration, the holder 20 for holding the secondary battery cell 1 and the circuit board 3 is provided with the holding portion 26. Thus, there is no need to prepare a separate member for providing the holding portion 26, and a mechanism for holding the lead plate 30 can be added by using an existing member and changing a part of its shape.

[0081] In addition, in the above example, an example is described in which the holding portion 26 for holding the lead plate 30 is provided on the holder portion 20, but the holding portion may be provided on other components. For example, a holding member may be provided on a dedicated battery holder for holding a secondary battery cell or a dedicated substrate holder for holding a circuit substrate. In addition, a dedicated member for providing the holding member may be added.

[0082] In addition, the present invention is not limited to directly connecting the connection area of ​​the lead plate and the circuit substrate, but can also be applied to the following structure: the connection area of ​​the lead plate electrically connected by welding is set on another connection member on the circuit substrate, and the connection area of ​​the connection member is relayed and connected to the circuit substrate.

[0083] Furthermore, the present invention is not limited to the region where the lead plate is connected to the circuit board, and can also be applied to the use of electrically connecting the lead plate to other components by laser welding, etc. For example, the lead plate and the housing, the lead plates each other, the lead plate and the bus bar, etc. can be cited.

[0084] In the above example, the battery pack is installed in the electrical device to be driven to supply power to the electrical device. In addition, when the remaining capacity of the battery pack decreases or the battery pack deteriorates over time, the battery pack can be replaced to continue using the electrical device. However, the present invention is not limited to replaceable battery packs that mainly accommodate secondary battery cells, but can also be applied to a method in which a secondary battery cell is accommodated in a housing of an electrical device. In the present disclosure, a battery pack only needs to accommodate a secondary battery cell in a housing, and a configuration in which a secondary battery cell for driving is built into the housing of the electrical device itself is also referred to as a battery pack. That is, the present invention is not limited to replaceable battery packs, but can also be applied to electrical devices with built-in secondary battery cells.

[0085] Industrial Applicability

[0086] The battery pack of the present invention can be suitably used as a power supply device for assisting mobile bodies such as bicycles and electric carts, and can also be suitably used as a power supply for wireless devices, power supplies for portable electrical equipment such as electric cleaners and electric tools, and the like.

[0087] Description of Reference Numerals

[0088] 100, 200, 300, 400...Battery pack

[0089] 1…Secondary battery cell

[0090] 2…Battery Module

[0091] 3…Circuit board

[0092] 4…Connection area

[0093] 10…External housing

[0094] 11, 12... cover part

[0095] 20…Retainer

[0096] 21A, 21B…divided housing

[0097] 22…Storage tube

[0098] 24…Loading surface

[0099] 25…Wall

[0100] 26, 26B, 26C, 26D ... holding portion; 26C1 ... flange-shaped; 26D1 ... locking portion

[0101] 27… Inclined surface

[0102] 30...Lead plate

[0103] 31…Bending line

[0104] 32, 32B, 32C, 32D…bending piece; 32D1…step part

[0105] 33…Laser welding area

[0106] 34, 34B, 34C…Window

[0107] 35…Second bending line

[0108] 37…Leaf spring

[0109] 38…Incision

[0110] 39…protrusion

[0111] 40…Insulation board

Claims

1. An electrical device comprising: a lead plate having a bent piece obtained by bending a portion of the lead plate along a bending line; a circuit substrate electrically connected to the bent piece of the lead plate; and a retainer portion, the retainer portion retaining the lead plate, The retainer portion is formed with a retaining portion that locks a portion of the upper surface of the bent piece. The holding portion is configured to hold the bent piece of the lead plate by contacting with a portion of the upper surface of the bent piece in a posture facing the direction of springback caused by bending the bent piece of the lead plate along the bending line. The circuit substrate includes a connection area electrically connected to the lead plate. The bending piece is electrically connected to the connection area.

2. The electrical device according to claim 1, The lead plate is formed with a through window portion, The holding portion is configured to hold the bent piece by contacting with a portion of the periphery of the window portion in a posture facing a direction in which the bent piece rebounds when the holding portion is inserted through the window portion of the lead plate.

3. The electrical device according to claim 1, The lead plate includes a laser welding region on a portion of a lower surface of the bent piece to be laser-welded to the connection region.

4. The electrical device according to claim 2, The holding portion is formed in a hook shape.

5. The electrical device according to claim 2, The lead plate has a leaf spring formed at an end edge of the window portion and at a position facing the holding portion.

6. The electrical device according to claim 2, The holding portion is formed in a columnar shape, The lead plate forms the window portion into a hole shape into which the columnar holding portion is inserted. The electric device is configured such that, in a state where the columnar holding portion is inserted into the hole-shaped window portion, the front end of the columnar holding portion is crushed to press the periphery of the hole-shaped window portion.

7. The electrical device according to claim 6, The holding portion is formed into a cylindrical shape, The window portion of the lead plate is formed into a circular shape into which the cylindrical holding portion is inserted. The electric device is configured such that, in a state where the cylindrical holding portion is inserted into the circular window portion, the front end of the cylindrical holding portion is flattened to press the periphery of the circular window portion.

8. The electrical device according to claim 1, The holding portion is integrally formed with the retainer portion.

9. The electrical device according to any one of claims 1 to 8, The electric device further includes one or more secondary battery cells connected to the circuit board via the lead plate. The holder portion is formed with the holding portion in a region around the circuit substrate. The electrical device is a battery pack.

10. The electrical device according to claim 1, The lead plate has stepped portions formed on its side surfaces when viewed from above. The holding parts are respectively arranged on the step parts of the lead plate, Each holding portion is provided with a locking portion for locking the upper surface of the step portion.

11. An electrical device comprising: a lead plate, a portion of which is bent; a circuit substrate, the circuit substrate being electrically connected to the lead plate; and a holder portion, the holder portion holding the lead plate, The lead plate is formed with a through window portion, The retainer portion includes a retaining portion that, when inserted through the window portion of the lead plate, abuts against a portion of a periphery of the window portion to retain the lead plate in a posture facing a direction in which springback occurs with respect to bending of the lead plate.

12. A method for manufacturing an electric device, the electric device comprising a lead plate, a circuit substrate electrically connected to the lead plate, and a holder portion for holding the lead plate, The manufacturing method of the electrical device comprises: The step of bending the lead plate, inserting a holding portion formed on the electrical device into a window portion opened in the lead plate, and holding the lead plate by abutting the holding portion against a portion of the periphery of the window portion; and A step of connecting the lead plate to the circuit board by laser welding while the lead plate is held by the holding portion.

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