JP2021150004A - Battery pack - Google Patents

Abstract

To secure a wide storage space in a battery pack without making its outer shape large.SOLUTION: A battery pack comprises: one or more secondary battery cells 1; a circuit board 4 mounted with a circuit connected electrically to the secondary battery cells 1; a holder part 20 including a space defined with one or more wall parts 8 as a storage space 9 and having one surface, communicating with the storage space 9, opened; a cover part 26 connected to the wall parts 8 to close the opening part of the holder part 20; and an outer package label 3 stuck on surfaces of the holder part 20 and the cover part 26 with the opening part of the holder part 20 closed with the cover part 26. The battery pack is coupled through a fitting coupling part 7 consisting of a fitting recessed part 7A and a fitting projection part 7B formed by forming the wall parts 8 and the cover part 26 in a dovetail shape in plan view.SELECTED DRAWING: Figure 6

Description

The present invention relates to a battery pack including a thin secondary battery cell and a circuit board.

A battery pack equipped with a rechargeable secondary battery cell is used as a power source for portable electronic devices such as smartphones, tablets, and notebook computers. As the secondary battery cell of the battery pack, a pouch battery that can be made thinner is used. On the other hand, due to portability and the like, there are increasing conflicting demands for miniaturization and high performance of battery packs.

Generally, a battery pack has a structure in which a secondary battery cell and a circuit board on which a charge / discharge control circuit and a protection circuit thereof are mounted are arranged in a case or a frame. Therefore, in order to improve the performance of the secondary battery cell, it is necessary to enlarge the secondary battery cell and the circuit board. In this case, in order to avoid increasing the size of the battery pack, it is necessary to secure a relatively large internal storage space, and the holding member side such as the case and the frame must be thinned.

As shown in FIG. 16, the holder and cover, which are holding members conventionally used in a thin battery pack, are provided with a claw 97 on the cover 96 side and a groove 94 on the holder 90 side to receive the claw 97. Claw fitting is adopted.

Japanese Unexamined Patent Publication No. 2013-080569

However, in such a fitting structure, as shown in FIG. 16, a claw 97 on the cover 96 side and three walls 92 and 93 on the holder 90 side sandwiching both sides of the claw 97 are required to have a thickness D2. As a result of the storage space 91 in the holder being compressed by such a thick wall, the storage space for the secondary battery cell, the circuit board, and the like has become smaller.

One of an object of the present invention is to provide a battery pack in which a wide internal storage space can be secured without enlarging the outer shape of the pack battery.

A battery pack according to an embodiment of the present invention is a space defined by one or more secondary battery cells, a circuit board on which a circuit electrically connected to the secondary battery cells is mounted, and one or more walls. As a storage space, a holder portion that opens one side that communicates with the storage space, a cover portion that is connected to the wall portion and closes the opening portion of the holder portion, and a state in which the opening portion of the holder portion is closed by the cover portion. , It is equipped with an exterior label attached to the surface of the holder portion and the cover portion. In the battery pack, the wall portion and the cover portion are connected via a fitting connecting portion formed of a fitting concave portion and a fitting convex portion formed in a dovetail shape in a plan view.

According to the battery pack of the present invention, a large internal storage space can be secured without enlarging the outer shape of the pack battery.

It is a perspective view of the battery pack which concerns on one Embodiment of this invention. It is an exploded perspective view of the battery pack shown in FIG. It is an exploded perspective view which further disassembled the battery pack shown in FIG. It is a partially enlarged plan view which removed the exterior label of the battery pack shown in FIG. It is a perspective view which shows an example of a secondary battery cell. It is an enlarged exploded perspective view which shows the connection structure of a holder part and a cover part. It is an enlarged plan view which shows an example of the fitting connection part. It is an enlarged plan view which shows another example of the mating connection part. It is an enlarged plan view which shows another example of the mating connection part. It is a cross-sectional perspective view which shows another example of a mating connection part. FIG. 10 is a vertical cross-sectional perspective view of the fitting connection portion shown in FIG. It is a cross-sectional perspective view which shows another example of a mating connection part. FIG. 12 is a vertical cross-sectional perspective view of the fitting connection portion shown in FIG. It is an enlarged exploded perspective view which shows another example of the connection structure of a holder part and a cover part. It is a bottom perspective view which shows the state which the 1st label is attached to the holding member which attached the 2nd label. It is an enlarged sectional view of the main part of the conventional battery pack.

The battery pack of the first embodiment of the present invention is defined by one or more secondary battery cells, a circuit board on which a circuit electrically connected to the secondary battery cells is mounted, and one or more walls. The storage space is used as a storage space, and the holder portion that opens one side that communicates with the storage space, the cover portion that is connected to the wall portion and closes the opening portion of the holder portion, and the opening portion of the holder portion are closed by the cover portion. In this state, the battery pack includes an exterior label attached to the surface of the holder portion and the cover portion, and the wall portion and the cover portion are formed in a dovetail shape in a plan view. It is connected via a fitting connecting portion composed of a portion.

According to the above configuration, the thickness of the wall portion can be reduced as compared with the conventional fitting structure in which the claws are provided on the cover portion side and received by the groove on the wall portion side, so that the storage space defined by the wall portion can be created. It is possible to secure a large size, and thus it is possible to secure a large storage space for the secondary battery cell, the circuit board, etc. without enlarging the outer shape of the battery pack.

In the present specification, the dovetail groove shape means a shape similar to a dovetail groove formed so that the cross-sectional shape has an inverted C shape. Therefore, the fitting recess formed in the shape of a dovetail groove in the plan view means the shape of the recess notched so as to gradually widen inward from the boundary surface in contact with each other in the plan view. The fitting convex portion formed in a dovetail shape in a plan view means a convex portion shape protruding from a boundary surface in contact with each other toward a fitting recess so as to gradually widen in a plan view. Shall be.

In the battery pack according to the second embodiment of the present invention, the wall portion has a stepped recess formed inside the tip portion along the opening edge of the holder portion, and the outside of the tip portion has a stepped protrusion. The outer peripheral edge portion is fitted into the stepped recess, and the outer peripheral surface of the cover portion is arranged so as to be close to the inner peripheral surface of the stepped convex portion.

With the above configuration, the outer peripheral edge of the cover is supported by the stepped recess provided in the wall of the holder, so that the cover and the wall are connected in close contact with each other while stably holding the cover. By doing so, the connected part can be made inconspicuous.

In the battery pack according to the third embodiment of the present invention, the fitting connection portion is formed by cutting out the outer peripheral edge portion of the cover portion in a dovetail groove shape in a plan view, and the fitting concave portion and the stepped protrusion of the wall portion. It is composed of a fitting convex portion formed in a shape that protrudes into the stepped concave portion and is fitted into the fitting concave portion.

According to the above configuration, the fitting concave portion formed on the outer peripheral edge portion of the cover portion is fitted and connected to the fitting convex portion formed by projecting from the stepped convex portion of the wall portion to the stepped concave portion, so that the cover portion is connected. Can be connected while reliably preventing misalignment. By arranging the outer peripheral edge of the cover part in the stepped recess, the cover part is stably supported, and the cover is covered by fitting the fitting recess formed in the shape of a dovetail groove in a plan view and the fitting ridge. This is because it is possible to reliably prevent the displacement of the front, back, left and right of the portion.
In particular, since the wall portion forms the fitting convex portion protruding from the stepped convex portion in the stepped concave portion, the fitting convex portion is formed in a space-saving manner without forming the wall portion thickly in order to form the fitting convex portion. can. Further, also in the cover portion, by forming a fitting recess in the outer peripheral edge portion, the fitting recess is fitted to the fitting convex portion and firmly connected, and the region of the outer peripheral edge portion without the fitting recess is formed. It is stably supported by placing it on the step recess.

In the battery pack according to the fourth embodiment of the present invention, the fitting connection portion has a fitting protrusion protruding outward from the outer peripheral edge of the cover portion in a dovetail shape in a plan view, and a stepped protrusion on the wall portion. , It is composed of a stepped recess formed by notching a dovetail groove shape to fit the fitting convex portion.

According to the above configuration, the fitting protrusion formed by projecting from the outer peripheral edge of the cover portion is fitted and connected to the fitting recess formed by notching the stepped protrusion of the wall portion, so that the cover portion can be connected. Can be connected while reliably preventing misalignment. By arranging the outer peripheral edge of the cover part in the stepped recess, the cover part is stably supported, and the cover is covered by fitting the fitting recess formed in the shape of a dovetail groove in a plan view and the fitting ridge. This is because it is possible to reliably prevent the displacement of the front, back, left and right of the portion.
In particular, since the wall portion is formed in the stepped recess by notching the stepped protrusion, the fitting recess can be formed in a space-saving manner without forming the wall portion thickly in order to form the fitting recess. Further, also in the cover portion, by forming a fitting convex portion protruding from the outer peripheral edge, the fitting convex portion is fitted into the fitting concave portion and firmly connected, and the outer peripheral edge portion is placed on the stepped concave portion. It is stably supported by.

In the battery pack of the fifth embodiment of the present invention, the fitting convex portion and the fitting concave portion form facing surfaces facing each other in an undercut shape.

According to the above configuration, on the facing surfaces of the fitting convex portion and the fitting concave portion, the facing surfaces formed in an undercut shape are brought into contact with each other to prevent the fitting convex portion from coming off from the fitting concave portion. , The cover part can be held so that it does not come off in the fixed position of the holder part.

In the battery pack of the sixth embodiment of the present invention, the fitting convex portion and the fitting concave portion are provided with moderation protrusions on either one of the facing surfaces facing each other and the moderation recesses for guiding the moderation protrusions on the other side. It is provided.

According to the above configuration, on the facing surface between the fitting protrusion and the fitting recess, the moderation protrusion is guided to the moderation recess to prevent the fitting protrusion from coming out of the fitting recess, and the cover portion is placed on the holder portion. Can be held so that it does not come off in place.

In the battery pack according to the seventh embodiment of the present invention, the holder portion is provided with wall portions that define a storage space on at least three sides, and each wall portion and the cover portion are fitted with a fitting connection portion. It is provided.

With the above configuration, the cover portions are connected by providing dovetail-shaped fitting connecting portions on the wall portions arranged on at least three sides that define the storage space, so that the misalignment of the cover portions can be reliably prevented and each of them can be prevented. By making the wall portions thin, it is possible to secure a wide storage space defined by these wall portions.

In the battery pack of the eighth embodiment of the present invention, the exterior label is attached so as to cover the fitting connection portion formed by connecting the wall portion and the cover portion.

With the above configuration, by attaching the exterior label to the cover portion and the wall portion fitted by the dovetail-shaped fitting connection portion, it is possible to reliably prevent the cover portion from coming off from the holder portion.

In the battery pack according to the ninth embodiment of the present invention, the exterior label attached to the surface side of the cover portion includes a plurality of folded pieces protruding from the outer peripheral edge, and the folded pieces are projected from the surface side of the cover portion. It is designed to be folded back and attached to the bottom surface side of the holder portion, and the folded-back piece is arranged in the area corresponding to the fitting connection portion.

According to the above configuration, a plurality of folded pieces are provided on the outer peripheral edge of the exterior label to be attached to the surface side of the cover portion, and the folded pieces are attached across the surface side of the cover portion to the bottom surface side of the holder portion. As a result, the exterior label can be firmly attached. In particular, by providing the folded piece in the region corresponding to the fitting connecting portion provided in the holder portion and the cover portion, the region connected via the fitting connecting portion can be held so as not to come off more reliably.

In the battery pack according to the tenth embodiment of the present invention, the storage space defined by the wall portion of the holder portion is used as a space for accommodating the circuit board. With the above configuration, it is possible to secure a wide storage space for the circuit board.

The battery pack according to the eleventh embodiment of the present invention includes a plurality of secondary battery cells, and the holder portion inserts the plurality of secondary battery cells side by side so that the main surfaces are flush with each other. The insertion space is formed like a window.

Hereinafter, the present invention will be described in detail with reference to the drawings. In the following description, terms indicating a specific direction or position (for example, "upper", "lower", and other terms including those terms) are used as necessary, but the use of these terms is used. This is for facilitating the understanding of the invention with reference to the drawings, and the meaning of these terms does not limit the technical scope of the present invention. Further, the parts having the same reference numerals appearing in a plurality of drawings indicate the same or equivalent parts or members.
Further, the embodiments shown below show specific examples of the technical idea of the present invention, and do not limit the present invention to the following. In addition, the dimensions, materials, shapes, relative arrangements, etc. of the components described below are not intended to limit the scope of the present invention to the specific description, but are exemplified. It was intended. Further, the contents described in one embodiment and the embodiment can be applied to other embodiments and the examples. In addition, the size and positional relationship of the members shown in the drawings may be exaggerated in order to clarify the explanation.

The battery pack of the present invention is mainly suitable for use as a power source for portable electronic devices such as smartphones, tablets, and notebook computers. However, the present invention does not specify the use of the battery pack, and can also be used as a power source for various other electronic devices.

(Embodiment 1)
The battery pack according to the embodiment of the present invention is shown in FIGS. 1 to 4. 1 is a perspective view of the battery pack, FIG. 2 is an exploded perspective view of the battery pack shown in FIG. 1, FIG. 3 is an exploded perspective view of the battery pack of FIG. 2, and FIG. 4 is a battery shown in FIG. A partially enlarged plan view of the pack with the exterior label removed is shown.

The battery pack 100 shown in FIGS. 1 to 4 includes one or more secondary battery cells 1, a circuit board 4 on which a circuit electrically connected to the secondary battery cells 1 is mounted, and one or more wall portions 8. The defined space is used as the storage space 9, and the holder portion 20 having an opening on one side communicating with the storage space 9, the cover portion 26 connected to the wall portion 27 and closing the opening of the holder portion 20, and the holder portion. The holder portion 20 and the exterior label 3 attached to the surface of the cover portion 26 are provided in a state where the opening of the 20 is closed by the cover portion 26.

In the battery pack 100 shown in the figure, a holding member 2 is composed of a holder portion 20 and a cover portion 26 forming a storage space 9 inside, and the secondary battery cell 1 and the circuit board 4 are attached to the holding member 2. It has a structure that can be stored and held in place. The battery pack 100 shown in FIGS. 1 to 4 includes three secondary battery cells 1 and is arranged on the holding member 2 so that the secondary battery cells 1 are arranged in the same plane. .. However, the battery pack of the present invention does not limit the number of secondary battery cells. The battery pack can include one secondary battery cell, or can include two or more secondary battery cells.

(Secondary battery cell 1)
The secondary battery cell 1 is a thin secondary battery having a flat shape as a whole, and as shown in FIG. 5, the outer shapes of the first main surface 1A and the second main surface 1B facing each other are quadrangular. .. Further, the secondary battery cell 1 is provided with positive and negative electrode terminals 15 at one end to serve as an output side end 1E, and the surface opposite to the output side end 1E is designated as an end face 1D. The surfaces on both sides of the main surface 1A and the second main surface 1B are designated as the side surface 1C.

The secondary battery cell 1 shown in FIG. 5 is a pouch battery in which the periphery of an electrode body (not shown) is covered with an exterior film 11. The thin pouch battery is a lithium ion polymer battery having a thickness of 3 mm to 10 mm. However, the present invention does not specify the pouch battery as a lithium ion polymer battery. The pouch battery can be any pouch battery that can be charged and discharged.

Furthermore, the present invention does not specify a secondary battery cell as a pouch battery. As the secondary battery cell, a secondary battery cell provided with a metal outer can can also be used as long as it is a flat thin battery having a quadrangular outer shape. As such a secondary battery cell, a thin square battery in which the opening of the metal outer can is airtightly closed by a sealing plate can be used. Therefore, the secondary battery cell may be a lithium ion battery or a nickel-hydrogen battery.

(Holding member 2)
The holding member 2 houses the secondary battery cell 1 and the circuit board 4 to which the secondary battery cell 1 is connected and holds the secondary battery cell 1 in a fixed position. The holding member 2 shown in the figure has a storage space 9 defined by a plurality of wall portions 8 formed inside, and is connected to a holder portion 20 having an opening on one side communicating with the storage space 9 and a wall portion 8. It is provided with a cover portion 26 that closes the opening of the holder portion 20. The holding member 2 shown in the figure has a structure in which the opening of the holder portion 20 formed in a frame shape by the wall portion 8 is partially closed by the cover portion 26. However, the holding member may have a structure in which the entire holder portion is formed into a container shape having a bottom plate, and the entire surface of the opening opened on one surface of the holder portion is closed by the cover portion.

(Holder part 20)
The holder portion 20 shown in FIG. 3 has a frame shape for holding the secondary battery cell 1 and the circuit board 4 along the outer peripheral edge, and has a first main surface 1A and a second main surface 1A of the secondary battery cell 1. The opening for exposing the surface 1B is opened on both sides. The holder portion 20 in the figure has a rectangular outer shape as a whole, and a substrate storage space 21 for accommodating the circuit board 4 is provided at an end portion along one side of the rectangle. Further, the holder portion 20 in the figure is provided with insertion spaces 22 for inserting the three secondary battery cells 1 side by side in the same plane in the extension direction of the circuit board 4, and the three secondary battery cells 1 are arranged. The electrode terminals 15 arranged at the output side end 1E of each secondary battery cell 1 are connected to the circuit board 4 while being arranged side by side.

(Wall 8 and intermediate wall 27)
In the holder portion 20 shown in FIGS. 2 to 4, a plurality of wall portions 8 along the outer peripheral edge define a storage space 9 inside, and a plurality of intermediate wall portions 27 are also provided inside, so that the storage space 9 is provided. Is partitioned into an insertion space 22 and a substrate storage space 21 of the secondary battery cell 1 so that a plurality of secondary battery cells 1 and a circuit board 3 can be stored while being positioned in the partitioned space. The wall portion 8 along the outer peripheral edge of the holder portion 20 is a pair of side wall portions 23 that cover both ends of the substrate storage space 21 and the outer side surface 1C of the secondary battery cell 1 arranged adjacent to each other, and a pair of side surfaces. An end face wall portion 24 that is connected to the wall portion 23 and covers the end surface 1D of the secondary battery cell 1 and a peripheral wall portion 25 that is arranged to face the end face wall portion 24 and covers one side of the battery storage space 21. I have. Further, the holder portion 20 in the figure is a first intermediate wall portion 27A arranged between adjacent secondary battery cells 1 as an intermediate wall portion 27 arranged inside, and an end face wall portion 24 and a peripheral wall portion. It is provided between the 25 and the second intermediate wall portion 27B to which one end of the first intermediate wall portion 27A is connected. The second intermediate wall portion 27B is formed inside the holder portion 20 in a posture parallel to the peripheral wall portion 25, and one end of the first intermediate wall portion 27A is connected at the intermediate portion. In this structure, the strength of the first intermediate wall portion 27A and the second intermediate wall portion 27B are integrally molded in an intersecting posture to enhance each other's strength. Further, the second intermediate wall portion 27B is provided with a notch portion 27a by cutting out a region facing the electrode terminal 15 of the secondary battery cell 1, and the electrode terminal 15 is passed through the notch portion 27a, or A lead plate (not shown) or the like connected to the electrode terminal 15 is passed through and connected to the circuit board 4.

(Insert space 22)
The holder portion 20 inserts the secondary battery cells 1 on both sides into the side wall portion 23 and the first intermediate wall portion 27A that cover the side surface 1C of the secondary battery cell 1 and the end face wall portion 24 that covers the end surface 1D. An insertion space 22 is provided, and the intermediate secondary battery cell 1 is inserted inside a pair of first intermediate wall portions 27A covering both side surfaces 1C of the secondary battery cell 1 and an end surface wall portion 24 covering the end surface 1D. An insertion space 22 is provided. The holder portion 20 positions the secondary battery cell 1 inserted into each insertion space 22 at a fixed position by the side wall portion 23, the first intermediate wall portion 27A, and the end face wall portion 24, while the output side end portion 1E The electrode terminals 15 arranged in the above are arranged so as to face the fixed positions of the circuit board 4.

(Board storage space 21)
Further, the holding member 2 is a substrate storage space for accommodating the circuit board 4 in an internal space formed by an end portion of the holder portion 20 and a cover portion 26 that closes the opening at the end portion of the holder portion 20. It is set to 21. The substrate storage space 21 shown in FIGS. 3 and 6 has a plurality of wall portions 8 and intermediate wall portions 27 along the outer peripheral edge of the circuit board 4 as a bottom plate of the holder portion 20 so that the elongated rectangular circuit board 4 can be accommodated. It is connected to the part 28 and defined. The substrate storage space 21 shown in the figure is a peripheral wall portion 25 provided so as to face one side on the long side side of the circuit board 4 and forming an outer peripheral surface of the holder portion 20, and two sides on the short side side of the circuit board 4. One end of the side wall portion 23 that is provided so as to face the outer peripheral wall of the holder portion 20 and is provided inside the holder portion 20 that is provided so as to face the other one side on the long side side of the circuit board 4. It is defined by a second intermediate wall portion 27B to be arranged.

(Cover part 26)
The cover portion 26 is a plastic plate material, which is a part of the opening of the holder portion 20, and is defined by a wall portion 8 and a second intermediate wall portion 27B arranged along the outer circumference of the circuit board 4. The opening of the space is closed. The cover portion 26 is connected to the upper end portion of the wall portion 8 in a fitting structure to close the opening of the holder portion 20. The wall portion 8 shown in FIG. 6 has a stepped recess 29 formed inside the tip portion along the opening edge of the holder portion 20 so that the cover portion 26 can be connected while positioning, and a stepped protrusion 29 is formed on the outside of the tip portion. 17 is provided. The cover portion 26 is connected to the holder portion 20 with the outer peripheral edge portion fitted to the stepped recess 29, and the outer peripheral surface thereof is brought close to the inner peripheral surface of the stepped convex portion 17. The depth of the step recess 29 is equal to the thickness of the cover portion 26, so that the holder portion 20 and the surface side of the cover portion 26 are flush with each other in a state where the cover portion 26 is fitted to the step recess 29. There is.

Further, in the battery pack 100 according to the present embodiment, in order to secure a wide storage space 9 formed inside the holder portion 20, the thickness of the wall portion 8 to which the cover portion 26 is connected is formed thinner than before. However, the structure is such that the cover portion 26 can be reliably connected. In order to realize this, in the battery pack according to the present embodiment, the wall portion 8 and the cover portion 26 are formed from a fitting recess 7A and a fitting protrusion 7B formed in a dovetail shape in a plan view. It is connected via the fitting connecting portion 7.

(Mating connection part 7)
As shown in FIG. 6, the fitting connecting portion 7 is formed by notching the outer peripheral edge portion of the cover portion 26 in a dovetail shape in a plan view from the fitting recess 7A and the stepped protrusion 17 of the wall portion 8. It is composed of a fitting convex portion 7B formed in a shape that protrudes into the stepped concave portion 29 and is fitted into the fitting concave portion 7A. As shown in the figure, the shape of the fitting connecting portion 7 that connects the holder portion 20 and the cover portion 26 is variously changed depending on the location, conditions, number, and the like where the fitting concave portion 7A and the fitting convex portion 7B are provided. .. Therefore, here, the structure will be described in detail by taking the fitting connection portion 7 shown in the enlarged plan view of FIG. 7 as an example.

(Mating recess 7A)
The fitting recesses 7A are a pair of inner side surfaces 26b and a pair of inner side surfaces 26b formed so as to gradually increase in width in an inverted C shape from the opening edge of the outer peripheral surface 26a of the cover portion 26 toward the inside. It is composed of a bottom surface 26c that connects the other ends of the above. The fitting recess 7A in the figure has an acute angle α formed by the outer peripheral surface 26a and the inner surface 26b of the cover portion 26 so that the width of the bottom surface 26c of the recess is wider than the opening width of the recess in a plan view. ing. The angle α formed by the outer peripheral surface 26a and the inner surface surface 26b is designed to be 20 to 75 degrees, more preferably 30 to 60 degrees, and even more preferably 40 to 50 degrees. The bottom surface 26c is provided parallel to the outer peripheral surface 26a including the opening edge of the recess in a plan view.

(Matching convex portion 7B)
The fitting convex portion 7B is an outer shape that is fitted into the fitting concave portion 7A, and is formed so as to gradually widen in an inverted C shape from the inner peripheral surface 17a of the stepped protrusion 17 toward the inside. It is composed of a pair of side surfaces 17b and a protruding end surface 17c formed by connecting the tips of the pair of side surfaces 17b. As shown in the figure, since the fitting convex portion 7B is formed to have an outer shape that follows the inner shape of the fitting concave portion 7A, the angle formed by the side surface 17b of the fitting convex portion 7B with the inner peripheral surface 17a of the stepped protrusion 17. With α as an acute angle, the width of the protruding end surface 17c at the tip is wider than the width of the rear end of the convex portion in a plan view. The angle α formed by the inner peripheral surface 17a and the side surface 17b of the stepped ridge 17 is 20 to 75 degrees, more preferably 30 to 60 degrees, further preferably 40 to 50 degrees, and the protruding end surface 17c is a step in a plan view. It is provided parallel to the inner peripheral surface 17a of the ridge 17.

The holder portion 20 shown in FIG. 4 is provided with wall portions 8 defining a storage space 9 on at least three sides, and a fitting connecting portion 7 is provided at each connecting portion between each wall portion 8 and the cover portion 26. .. The holder portion 20 and the cover portion 26 shown in FIG. 4 are provided with fitting connecting portions 7 at three locations of the peripheral wall portion 25 which is the peripheral wall 8 along the long side of the circuit board 4, and the peripheral wall along the short side of the circuit board 4. One fitting connecting portion 7 is provided on each of the side wall portions 23 on both sides, which is 8. Since this structure and the cover portion 26 can be connected while being positioned on three sides, there is a feature that the misalignment of the cover portion 26 can be reliably prevented. However, the position and number of fitting connecting portions provided in the connecting portion between the holder portion 20 and the cover portion 26 can be variously changed according to the size and shape of the cover portion.

(Other examples of mating joints)
As described above, the fitting concave portion 7A and the fitting convex portion 7B formed in a dovetail shape in a plan view are preferably formed so as to be gradually widened in an inverted C shape. However, the fitting concave portion and the fitting convex portion do not necessarily have the inner peripheral surface and the side surface formed in an inverted C shape as flat inclined surfaces, and may be curved surfaces. In the fitting recess 7A shown in FIG. 8, the inner side surface 26d cut out inward from the outer peripheral surface 26a is a curved surface of the central concave, and the side surface 17d of the fitting convex portion 7B facing the curved surface is the curved surface of the central convex. .. In this case, the angle formed by the curved inner side surface 26d and the outer peripheral surface 26a at the opening edge of the fitting recess 7A may be an acute angle smaller than 20 degrees.

Further, in the fitting recess 7A shown in FIG. 9, the inner side surface 26e notched inward from the outer peripheral surface 26a is a curved surface having a central convexity, and the bottom surface 26f connecting the inner side surfaces on both sides is also a curved surface. In the fitting recess 7A of FIG. 9, the bottom surface 26f is a curved surface of the central recess. Further, in the fitting convex portion 7B to be fitted with the fitting concave portion 7A, the side surface 17e facing the inner side surface 26e is a curved surface having a central concave shape, and the protruding end surface 17f facing the bottom surface 26f is a curved surface having a central convex shape. It is said. The fitting concave portion 7A and the fitting convex portion 7B shown in the figure have a substantially ginkgo leaf shape as a whole in a plan view.

Further, although not shown, the fitting connecting portion can have various shapes in which the fitting concave portion and the fitting convex portion are similar to the dovetail shape in a plan view. For example, the fitting concave portion can have various concave shapes notched so as to gradually increase in width from the outer peripheral surface toward the inside in a plan view, and the fitting convex portion fits into the fitting concave portion. It is possible to have various convex shapes that protrude so as to gradually increase in width in a plan view. That is, in the present specification, these shapes are collectively referred to as a dovetail shape.

The fitting connecting portion 7 is surely connected at a predetermined position by suppressing the movement in the front-back and left-right directions by the fitting concave portion 7A and the fitting convex portion 7B that are fitted to each other. By moving the cover portion 26 in parallel in the thickness direction of the cover portion 26, the fitting connecting portion 7 guides the fitting concave portion 7A of the cover portion 26 to the fitting convex portion 7B of the wall portion 8 and is in a mated state. It is connected by. The holder portion 20 and the cover portion 26, which are fitted via the fitting connecting portion 7, are restricted from moving back and forth and left and right by the fitting structure, but can move in the insertion direction of the cover portion 26. Therefore, the exterior label 3, which will be described later, is attached to the surface of the cover portion 26 and held in place so that the cover portion 26 connected to the holder portion 20 does not come off.

Further, the fitting connecting portion 7 may have a structure in which the fitting concave portion 7A and the fitting convex portion 7B to be fitted to each other are connected so as not to come off. The fitting recesses 7A and the fitting protrusions 7B shown in FIGS. 10 and 11 are connected to each other by forming facing surfaces facing each other in an undercut shape so as not to come off. The fitting connecting portion 7 shown in FIG. 10 has an undercut shape on both inner side surfaces 26b of the fitting recess 7A and both side surfaces 17b of the fitting convex portion 7B. Further, in the fitting connecting portion 7 shown in FIG. 11, the bottom surface 26c of the fitting recess 7A and the protruding end surface 17c of the fitting convex portion 7B have an undercut shape. In the above structure, the fitting convex portion 7B is formed into the fitting concave portion by bringing the side surface 17b and the inner side surface 26b formed in an undercut shape into contact with each other on the facing surface of the fitting convex portion 7B and the fitting concave portion 7A. The cover portion 26 can be held so as not to come off from the fixed position of the holder portion 20 by preventing the cover portion 26 from coming off from the 7A. The fitting connection portion 26 shown in the figure is connected to each other by press-fitting the cover portion 26 into the holder portion 20, in other words, by press-fitting the fitting recess 7A into the fitting convex portion 7B.

Here, in the fitting connecting portion 7 shown in FIG. 10, the inclination angle (β2) of the side surface 17b formed in an undercut shape and the inclination angle (β1) of the inner side surface 26b are made equal to each other. Further, in the fitting connecting portion 7 shown in FIG. 11, the inclination angle (β2) of the protruding end surface 17c formed in the undercut shape and the inclination angle (β1) of the bottom surface 26c are made equal to each other. However, although not shown, the fitting connecting portion 7 is also formed in an undercut shape by making the inclination angle (β1) of the inner side surface smaller than the inclination angle (β2) of the side surface formed in the undercut shape. It is also possible to make the inclination angle (β1) of the bottom surface smaller than the inclination angle (β2) of the protruding end face. According to this structure, the cover portion can be easily press-fitted into the holder portion.

Further, the fitting connecting portion 7 shown in FIGS. 12 and 13 is provided with a moderation protrusion 38 on one of the facing surfaces of the fitting concave portion 7A and the fitting convex portion 7B facing each other, and the other. Is provided with a moderation recess 39 guided by the moderation protrusion 38. The fitting connecting portion 7 shown in the figure is provided with moderation protrusions 38 on the side surface 17b and the protruding end surface 17c of the fitting convex portion 7B, and is the inner side surface 26b and the bottom surface 26c of the fitting recess 7A and faces the moderation protrusion 38. A moderation recess 39 is provided. However, although not shown, the fitting connection portion may be provided with a moderation protrusion on the inner side surface or the bottom surface of the fitting recess, and the moderation recess may be provided on the side surface or the protruding end surface of the fitting protrusion. The above structure prevents the fitting protrusion 7B from coming out of the fitting recess 7A by guiding the moderation protrusion 38 to the moderation recess 39 on the facing surface between the fitting protrusion 7B and the fitting recess 7A. The cover portion 26 can be held so as not to come off in the fixed position of the holder portion 20.

The above-mentioned fitting connecting portion 7 shows an example in which the fitting concave portion 7A is provided in the cover portion 26 and the fitting convex portion 7B is provided in the wall portion 8, but the fitting connecting portion 7 is as shown in FIG. The cover portion 26 may be provided with a fitting convex portion 7D, and the wall portion 8 may be provided with a fitting concave portion 7C. The fitting connecting portion 7 shown in this figure fits the fitting convex portion 7D protruding outward in a dovetail shape from the outer peripheral edge of the cover portion 26 in a dovetail shape and the stepped protrusion 17 of the wall portion 8. It is composed of a stepped recess 7C formed by notching a dovetail groove shape into which the convex portion 7D is fitted. The fitting convex portion 7D shown in the figure has a pair of side surfaces 26g formed so as to gradually widen in an inverted C shape from the outer peripheral surface of the cover portion 26 toward the outside, and the tips of the pair of side surfaces 26g. It is composed of a protruding end face 26h formed by connecting the above. The fitting recess 7C is a pair of inner side surfaces 17g formed by notching from the opening edge formed on the inner peripheral surface 17a of the stepped ridge 17 so as to gradually widen in an inverted C shape toward the outside. And a support surface 17h formed in the same plane as the stepped surface of the stepped recess 29.

In the fitting connecting portion 7 having the above structure, the fitting convex portion 7D protruding from the outer peripheral edge of the cover portion 26 is fitted into the fitting concave portion 7C formed by notching the stepped protrusion 17 of the wall portion 8. By connecting them together, the cover portion 26 can be connected while being surely prevented from being displaced. Further, although not shown, even in the fitting connection portion of this structure, the fitting protrusions can be formed by forming the facing surfaces of each other in an undercut shape or by providing the moderation protrusions and the moderation recesses on the facing surfaces of each other. It is also possible to have a structure that can be connected so as not to come off from the fitting recess.

(Protruding part 19)
Further, as shown in FIGS. 1 to 4, the holder portion 20 is provided with a plurality of projecting portions 19 projecting outward from the outer peripheral surface by integrally molding. The protruding portion 19 is used as a positioning convex portion for positioning and a connecting convex portion for fixing when the battery pack 100 is attached to a portable electronic device. The holding member 2 in the figure includes one connecting convex portion 19A protruding from each of the facing side wall portions 23, five positioning convex portions 19B protruding from the end face wall portion 24, and both ends of the peripheral wall portion 25. It is provided with two positioning convex portions 19B protruding from the portions.

The holder portion 20 and the cover portion 26 are made of plastic. As the plastic for molding the holder portion 20 and the cover portion 26, for example, polycarbonate is suitable. Polycarbonate is easy to mold and has excellent strength. Further, since polycarbonate is excellent in flame retardancy, for example, when polycarbonate is used as the material of the holding member, even if the plate thickness is reduced to 0.8 mm, the flame retardancy defined by UL standards and the like is defined. Can meet the criteria for. Therefore, the holding member of polycarbonate can be made thinner while maintaining flame retardancy, and the size of the battery pack can be reduced accordingly. However, since plastics other than polycarbonate can be used as the plastic of the holding member, the plastic is not specified as polycarbonate.

(Circuit board 4)
The circuit board 4 mounts an electronic component that realizes a protection circuit for the secondary battery cell 1 and the like. The protection circuit detects the temperature and voltage of the secondary battery cell 1 and controls the charging / discharging current. In order to realize this, the circuit board 4 has a voltage detection circuit (not shown) that detects the voltage of the secondary battery cell 1, and safety of a breaker, a PTC element, a fuse, etc. that protect the secondary battery cell 1. A component, a temperature sensor that detects the temperature of the secondary battery cell 1, and a semiconductor switching element (not shown) such as an FET that controls the current of the secondary battery cell 1 are mounted.

The circuit board 4 can be housed in the holding member 2 in a state where the secondary battery cell 1 is connected and the battery is assembled. For example, in the secondary battery cell 1, the electrode terminal 15 is circuited via a lead plate (not shown) or a protective element (not shown) in a state where the electrode terminal 15 is accurately positioned with respect to the circuit board 4 via a jig or the like. It can be connected to the substrate 4 to assemble a battery. However, in the battery pack, after the circuit board and the plurality of secondary battery cells are arranged at fixed positions of the holding member 2, the electrode terminals 15 of the secondary battery cells 1 can be connected to the circuit board 4. The lead plate and the protective element are connected to the electrode terminal 15 of the secondary battery cell 1 by resistance spot welding or laser welding, and are connected to the circuit board 4 by resistance spot welding, laser welding, or soldering.

In the battery pack 100 shown in FIGS. 1 to 4, a leader wire 35 connected to the circuit board 4 is pulled out from the holding member 2. The leader line 35 connects the connector 36 to the tip. The leader line 35 is arranged at a fixed position via the circuit board 4 housed in the holding member 2.

(Exterior label 3)
The exterior label 3 is a plastic sheet having an adhesive layer on the inner surface. The exterior labels 3 of FIGS. 2 and 3 include a first label 3A and a second label 3B, which are affixed to both sides of the holding member 2, respectively. The first label 3A is attached to the bottom surface side of the holder portion 20, and the second label 3B is attached to the front surface side of the holder portion 20 to which the cover portion 26 is connected. The outer shape of the first label 3A and the second label 3B is equal to the outer shape of the holder portion 20.

Further, the second label 3B has a plurality of folded pieces 31 along the outer peripheral edge, and these folded pieces 31 are folded back at the outer peripheral edge of the holder portion 20 and attached to the bottom surface side. .. The second label 3B shown in FIGS. 2 and 3 is provided with a plurality of folded pieces 31 protruding outward from the four sides of the rectangular main body portion 30 having an outer shape equal to the outer shape of the holder portion 20. As shown in FIG. 15, the second label 3B has the main body portion 30 attached along the outer peripheral edge of the holder portion 20, and the folded-back piece 31 protruding from the four sides is folded back at the outer peripheral edge to form the holder portion. It is attached so as to straddle the bottom surface side from the wall portion 8 of 20. As shown in FIG. 15, the folded piece 31 folded back to the bottom surface side is attached by extending from the wall portion 8 to the first main surface 1A of the secondary battery cell 1 on the bottom surface side of the holder portion 20. , Attached to the bottom plate portion 28.

The folded piece 31 of the second label 3B is arranged so as to avoid a plurality of protruding portions 19 protruding outward from the outer peripheral surface of the holding member 2. In other words, the folded piece 31 is provided at a position that does not correspond to the protruding portion 19. These folded pieces 31 are surely attached to the outer peripheral surface while avoiding the protruding portion 19 of the holding member 2. The holding member 2 in the figure is provided with a shallow step portion on the outer peripheral surface where the folded piece 31 is attached, and the folded piece 31 is adhered to the portion to prevent the outer shape of the battery pack 100 from becoming large. There is.

The first label 3A attached to the bottom surface side of the holder portion 20 has a rectangular shape having an outer shape equal to the outer shape of the holder portion 20, and is attached along the outer peripheral edge of the holder portion 20 as shown in FIG. ..

In the battery pack 100 shown in the figure, a first label 3A and a second label 3B composed of two labels are attached to both sides of the holding member 2. Although not shown, the pack battery may be composed of a first label and a second label as one label, folded back in the middle, and attached to both sides of the holding member. This label may be provided with an opening between the first label and the second label to expose the protruding portion of the holding member.

The above battery pack is assembled by the following process.
1. 1. The secondary battery cell 1 is connected to the circuit board 4 to assemble the battery. In the secondary battery cell 1, positive and negative electrode terminals 15 are connected to the circuit board 4 via a lead plate and a protective element.
2. The battery assembly is stored in the fixed position of the holder portion 20. At this time, the secondary battery cell 1 is inserted into the insertion space 22 of the holder portion 20 and held at a fixed position, and the circuit board 2 is set at a fixed position of the board storage space 21.
3. 3. The opening of the holder portion 20 is closed by the cover portion 26. The outer peripheral edge of the cover portion 26 is fitted into a stepped recess 29 provided in the wall portion 8 of the holder portion 20. The wall portion 8 and the cover portion 26 are connected to each other via a fitting connecting portion 7 including a fitting concave portion 7A formed in a dovetail shape and a fitting convex portion 7B in a plan view.
4. The second label 3B is attached to the surface of the holder portion 20 to which the cover portion 26 is connected. The second label 3B is attached so that the outer peripheral edge of the main body portion 30 coincides with the outer peripheral edge of the holder portion 20 and covers the fitting connecting portion 7 formed by connecting the wall portion 8 and the cover portion 26. .. Further, a plurality of folded pieces 31 protruding from the outer peripheral edge of the main body portion 30 are folded back at the outer peripheral edge of the holder portion 20 and attached so as to straddle the outer peripheral surface of the holder portion 20 to the bottom surface side.
5. Further, the first label 3A is attached to the bottom surface side of the holder portion 20 to which the second label is attached. The first label 3A is attached so that the outer peripheral edge coincides with the outer peripheral edge of the holder portion 20.

The battery pack of the present invention is conveniently used by being built in a portable electronic device such as a smartphone, a tablet, or a notebook computer.

100 ... Battery pack 1 ... Secondary battery cell 1A ... First main surface 1B ... Second main surface 1C ... Side surface 1D ... End surface 1E ... Output side end 2 ... Holding member 3 ... Exterior label 3A ... First label 3B ... Second label 4 ... Circuit board 7 ... Fitting connector 7A, 7C ... Fitting recess 7B, 7D ... Fitting convex part 8 ... Wall part 9 ... Storage space 11 ... Exterior film 15 ... Electrode terminal 17 ... Step Convex 17a ... Inner peripheral surface 17b, 17d, 17e ... Side surface 17c, 17f ... Protruding end surface 17g ... Inner side surface 17h ... Support surface 19 ... Protruding portion 19A ... Connecting convex portion 19B ... Positioning convex portion 20 ... Holder portion 21 ... Substrate Storage space 22 ... Insertion space 23 ... Side wall part 24 ... End face wall part 25 ... Peripheral wall part 26 ... Cover case 26a ... Outer surface 26b, 26d, 26e ... Inner side surface 26c, 26f ... Bottom surface 26g ... Side surface 26h ... Protruding end face 27 ... Intermediate wall portion 27A ... First intermediate wall portion 27B ... Second intermediate wall portion 27a ... Notch portion 28 ... Bottom plate portion 29 ... Connecting recess 30 ... Main body portion 31 ... Folded piece 35 ... Leader wire 36 ... Connector 38 ... Moderation protrusion 39 ... Moderation recess 90 ... Holder 91 ... Storage space 92, 93 ... Wall 94 ... Groove 96 ... Cover 97 ... Claw

Claims (11)

With one or more rechargeable batteries
A circuit board on which a circuit electrically connected to the secondary battery cell is mounted,
A space defined by one or more wall parts is used as a storage space, and a holder part having an opening on one side communicating with the storage space.
A cover portion that is connected to the wall portion and closes the opening of the holder portion, and a cover portion.
With the opening of the holder portion closed by the cover portion, the outer label affixed to the surface of the holder portion and the cover portion, and
It is a battery pack equipped with
The wall portion and the cover portion
A battery pack characterized in that it is connected via a fitting connecting portion composed of a fitting concave portion and a fitting convex portion formed in a dovetail shape in a plan view. The battery pack according to claim 1.
The wall part
A step recess is formed inside the tip portion along the opening edge of the holder portion, and the outside of the tip portion is a step protrusion.
The outer peripheral edge of the cover is fitted into the stepped recess,
A battery pack characterized in that the outer peripheral surface of the cover portion is arranged so as to be close to the inner peripheral surface of the stepped convex portion. The battery pack according to claim 2.
The fitting connection portion
The fitting recess formed by cutting out the outer peripheral edge portion of the cover portion in a dovetail groove shape in a plan view,
The fitting convex portion formed in a shape that protrudes from the step convex portion of the wall portion to the step concave portion and is fitted into the fitting concave portion.
A battery pack characterized by being composed of. The battery pack according to claim 2.
The fitting connection portion
The fitting convex portion protruding outward from the outer peripheral edge of the cover portion in a dovetail groove shape in a plan view,
A battery pack characterized in that the stepped protrusions on the wall portion are formed by notching the stepped protrusions in the shape of a dovetail to fit the fitting protrusions. The battery pack according to claim 3 or 4.
The fitting protrusion and the fitting recess
A battery pack characterized in that facing surfaces facing each other are formed in an undercut shape. The battery pack according to claim 3 or 4.
The fitting protrusion and the fitting recess
A battery pack characterized in that a moderation protrusion is provided on one of the facing surfaces facing each other, and a moderation recess for guiding the moderation protrusion is provided on the other side. The battery pack according to any one of claims 1 to 6.
The holder portion is provided with the wall portion that defines the storage space on at least three sides.
A battery pack characterized in that the fitting connecting portion is provided at each connecting portion between each wall portion and the cover portion. The battery pack according to any one of claims 1 to 7.
The exterior label
A battery pack characterized in that it is attached so as to cover the fitting connecting portion formed by connecting the wall portion and the cover portion. The battery pack according to claim 8.
The exterior label affixed to the surface side of the cover portion
It has multiple folded pieces that protrude from the outer periphery,
The folded piece is folded back from the front surface side of the cover portion to the bottom surface side of the holder portion and attached.
A battery pack characterized in that the folded piece is arranged in a region corresponding to the fitting connection portion. The battery pack according to any one of claims 1 to 9.
A battery pack characterized in that the holder portion serves as a storage space defined by the wall portion as a space for accommodating the circuit board. The battery pack according to any one of claims 1 to 10.
It is equipped with a plurality of the secondary battery cells.
A battery pack characterized in that the holder portion forms an insertion space in which the plurality of secondary battery cells are inserted side by side so that their main surfaces are flush with each other in a window shape.

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