JP2013004298A - Battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure with high shock resistance by a simple and low-cost configuration, in a battery pack having a unit cell attached with a protection circuit board.SOLUTION: A battery pack (1) comprises: a unit cell (2) having a positive electrode terminal (11) and a negative electrode terminal (12); a protection frame (4) which has walls (4a) in three directions so as to form an opening (4b), and which is attached to the unit cell (2) so that the opening (4b) is opened to the outside; and a protection circuit board (3) which is electrically connected to the positive electrode terminal (11) and the negative electrode terminal (12), and which is arranged inside the opening (4b) of the protection frame (4).

Description

  The present invention relates to a battery pack having a configuration in which a protection circuit board is attached to a unit cell.

  Conventionally, a battery pack having a configuration in which a protection circuit board is attached to a unit cell is known. In such a battery pack, for example, as disclosed in Patent Document 1, a protection circuit board is attached to a side surface of a square flat battery (unit cell). In such a battery pack, when the battery pack is removable from the device, the battery and the protective circuit board are covered with a resin outer frame. On the other hand, in the case of a battery pack of a type incorporated in a device, the battery and the protection circuit board are covered with a heat shrinkable tube or a label.

JP 2011-3510 A

  As described above, since the battery pack of the type incorporated in the device only covers the battery and the protection circuit board with a heat-shrinkable tube or label, the manufacturing cost of the battery pack is reduced compared to the battery pack removable from the device. Can be planned. In addition, since the outside of the battery is only covered with a heat-shrinkable tube or label, the battery pack can be reduced in size. In other words, even in the same space, a battery pack having a larger capacity can be mounted in the device.

  However, even if the battery pack is incorporated in the device as described above, there is a risk of dropping or a shock until the battery pack is incorporated in the device in the device manufacturing process. For this reason, the battery pack needs to have a certain degree of impact resistance. Even in this case, a low-cost and compact battery pack is desired.

  An object of the present invention is to realize a configuration with high impact resistance by a simple and low-cost configuration in a battery pack in which a protection circuit board is attached to a unit cell.

  A battery pack according to an embodiment of the present invention has a unit cell having an external terminal, and walls in three directions so as to form an opening, and the opening is opened outward. A protection frame attached to the unit cell; a protection circuit board electrically connected to the external terminal; and disposed in an opening of the protection frame; the unit cell, the protection frame, and the protection circuit board; And a film member covering the unit cell and the protective frame so as to be integrated (first configuration).

  With the above configuration, the protection circuit board can be protected by the protection frame attached to the unit cell in a simple configuration in which the unit cell and the protection frame are covered with the film member. That is, since the protection circuit board is disposed in the protection frame, it is possible to prevent the battery pack from being damaged even when the battery pack receives an impact.

  In addition, since the protective frame has wall portions in three directions so as to form an opening, and is attached to the unit cell so that the opening opens outward, the protective circuit board is attached to the protective frame. Can be easily inserted into the opening. Thereby, the protection circuit board can be easily assembled to the protection frame.

  In addition, as described above, the battery and the protective frame are covered with a film member, so that the battery is compared with a configuration in which the unit cell 2 is covered with a resin frame member or a part of the unit cell 2 is covered with a resin. The manufacturing cost of the pack can be reduced and the battery pack can be downsized.

  In the first configuration, the protective frame is attached to the unit cell other than a portion where the external terminal is provided (second configuration). As a result, the protective frame is arranged at a position that does not overlap the external terminals with respect to the unit cell, so the lead plate extending from the protective circuit board arranged in the protective frame can be easily connected to the external terminals outside the protective frame. can do. Therefore, the protection circuit board can be easily attached to the unit cell by the above-described configuration.

  In the first or second configuration, the protection circuit board is disposed in the protection frame so as to be inserted in a plane direction with respect to the opening (third configuration). Thereby, the protection circuit board can be easily inserted into the protection frame. In addition, in the above configuration, the lead plate can be positioned on the unit cell only by bending the lead plate connected to the protection circuit board. Thereby, the workability | operativity at the time of assembling a battery pack can be aimed at.

  In any one of the first to third configurations, the wall portion of the protective frame is provided with a holding portion for holding the protective circuit board (fourth configuration). Thereby, since the protection circuit board can be held by the holding portion in the protection frame, the protection circuit board can be prevented from moving and being damaged in the protection frame.

  In the fourth configuration, the protection circuit board includes a substrate and a mounting component mounted on the substrate, and the holding portion prevents the mounting component from contacting a wall portion of the protection frame. The protection circuit board is configured to protrude from the wall portion to the inside of the protection frame (fifth configuration).

  In this way, the holding part can prevent the wall part of the protective frame and the mounting part of the protective circuit board from being contacted, so that when the battery pack receives an impact, the mounting part of the protective circuit board and the wall part of the protective frame It can prevent contact and damage.

  In the fourth configuration, the holding portion is a protruding portion for locking the protective circuit board in the protective frame (sixth configuration). Thereby, even when an impact is applied to the battery pack, it is possible to prevent the protection circuit board from jumping out of the protection frame and being damaged.

  In any one of the first to sixth configurations, the unit cell is formed in a flat plate shape having a width dimension and a length dimension that are larger than a thickness dimension, and the protection frame includes the element frame. On the side surface extending in the thickness direction of the battery, the opening is attached so as to open in the thickness direction of the unit cell (seventh configuration).

  Thereby, a protection frame and a protection circuit board can be more compactly attached to a unit cell formed in a flat plate shape. In addition, when the shape of the unit cell is a flat plate as described above, a large force is applied to the side surface when an impact is applied to the side surface extending in the thickness direction of the battery pack. Since the impact is received on a relatively wide surface of the battery pack, a large force is not applied to the protection circuit board in the protection frame. Therefore, by attaching the protective frame so that the opening thereof opens in the thickness direction of the unit cell, the impact applied to the side surface extending in the thickness direction can be received by the wall portion of the protective frame, and the protective circuit in the protective frame The substrate can be protected more reliably.

  According to the battery pack of one embodiment of the present invention, the protective frame is attached to the unit cell so that the opening portion opens outward, and the protective circuit board is disposed in the protective frame. Thereby, it is possible to prevent the protection circuit board from being damaged when the battery pack receives an impact with a simple and low-cost configuration.

FIG. 1 is a perspective view showing an overall configuration of a battery pack according to an embodiment of the present invention. FIG. 2 is a longitudinal sectional view showing the battery pack in a cross section excluding the unit cell and the external cable. FIG. 3 is a perspective view showing a schematic configuration of the protection frame. FIG. 4 is a perspective view showing how a protective frame is attached to a unit cell in an example of a battery pack manufacturing method. FIG. 5 is a perspective view showing a state in which the wiring unit is inserted into the protective frame in an example of the battery pack manufacturing method. FIG. 6 is a perspective view showing a state in which the wiring unit is arranged in the protective frame in an example of the battery pack manufacturing method. FIG. 7 is an exploded perspective view showing an example of a method for manufacturing a wiring unit. FIG. 8 is a partial cross-sectional view showing a schematic configuration of a protective frame of a battery pack according to another embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are denoted by the same reference numerals and description thereof will not be repeated.

(overall structure)
FIG. 1 is a perspective view showing a schematic configuration of a battery pack 1 according to an embodiment of the present invention. The battery pack 1 includes a unit cell 2 that is a unit cell, and an output cable 37 that is led out from a wiring unit 7 attached to the unit cell 2. The battery pack 1 is electrically connected to the inside of an electric device (not shown) via the output cable 37. That is, the battery pack 1 according to the present embodiment is a battery pack that is used in a state of being incorporated in the electric device without being removed from the electric device (not shown).

  In FIG. 1, reference numeral 5 denotes an outer tube (film member) that covers the unit cell 2 and a protective frame 4 to be described later, and reference numeral 6 denotes a label on which the model number of the battery pack 1 is displayed. The outer tube 5 covers the unit cell 2 and the protection frame 4 so as to integrate the unit cell 2, the wiring unit 7 and a protection frame 4 described later. Accordingly, the manufacturing cost of the battery pack 1 can be reduced and the battery pack 1 can be reduced in size as compared with the configuration in which the unit cell 2 is covered with a resin frame member or the unit cell 2 is partially covered with resin. Can be realized.

  FIG. 2 is a longitudinal sectional view showing the battery pack 1 in a cross section excluding the unit cell 2 and the output cable 37. The battery pack 1 includes a unit cell 2, a protection circuit board 3, and a protection frame 4 that is attached to the unit cell 2 and accommodates the protection circuit board 3. As shown in FIGS. 1 and 2, the battery pack 1 as a whole has a width dimension (lateral dimension in FIGS. 1 and 2) and a length longer than a thickness dimension (dimension in the drawing depth direction in FIGS. 1 and 2). It is formed in a flat plate shape having a large dimension (vertical dimension in FIGS. 1 and 2).

  Further, as shown in FIGS. 1 and 2, the battery pack 1 includes center portions of an upper surface and a lower surface of the unit cell 2 to be described later (upper surface and lower surface in FIGS. 1 and 2, respectively). The unit cell 2 and the protective frame 4 are covered with an outer tube 5 except for. In FIG. 2, reference numeral 13 denotes an insulating plate.

  Although not particularly illustrated, the unit cell 2 includes a bottomed rectangular tube-shaped outer can, a cover plate covering the opening of the outer can, and an electrode body housed in the outer can. The unit cell 2 is configured by attaching a cover plate to the outer can by laser welding or the like in a state where the electrode body or the like is housed in the outer can. As shown in FIG. 2, the unit cell 2 has a longitudinal direction (FIG. 2) rather than a lateral direction (lateral direction in FIG. 2, hereinafter the same) when viewed from the thickness direction (the depth direction in FIG. 2, the same applies hereinafter). 2 is formed in a rectangular shape having a long length in the vertical direction (hereinafter the same). Further, nickel-aluminum clad (nickel-aluminum clad material, the same applies hereinafter) functioning as a positive electrode terminal (external terminal) at the end opposite to the cover plate of the unit cell 2 (upper end in FIG. 2). ) The plate 11 is attached by laser welding or the like. Here, the outer can and the cover plate are made of, for example, aluminum or an aluminum alloy. The positive electrode terminal may be a member made of a material other than nickel and aluminum clad.

  Although not particularly illustrated, the electrode body housed in the unit cell 2 is, for example, a spiral shape in which the positive electrode and the negative electrode formed in a sheet shape are overlapped so that the separator is positioned between the two. It is a wound electrode body formed by winding. The electrode body is formed in a flat shape by being wound in a state where the positive electrode, the negative electrode, and the separator are overlapped, and then being crushed. In addition to the electrode body, a nonaqueous electrolytic solution (hereinafter simply referred to as an electrolytic solution) is also enclosed in the unit cell 2.

  Here, the positive electrode constituting a part of the electrode body has a positive electrode active material layer containing a positive electrode active material provided on both surfaces of a positive electrode current collector made of metal foil such as aluminum. Specifically, the positive electrode is formed by applying a positive electrode mixture containing a positive electrode active material, a conductive auxiliary agent, a binder, and the like, which is a lithium-containing oxide capable of inserting and extracting lithium ions, onto a positive electrode current collector made of aluminum foil or the like. And dried.

  Moreover, the negative electrode which comprises a part of electrode body provides the negative electrode active material layer containing a negative electrode active material on both surfaces of the negative electrode collector made from metal foil, such as copper, respectively. Specifically, the negative electrode is formed by applying and drying a negative electrode mixture containing a negative electrode active material capable of occluding and releasing lithium ions, a conductive additive and a binder on a negative electrode current collector made of copper foil or the like. Is done.

  Although not particularly shown, in the unit cell 2, a positive electrode lead is connected to the positive electrode of the electrode body, while a negative electrode lead is connected to the negative electrode. The positive electrode lead is electrically connected to the cover plate inside the unit cell 2. That is, the cover plate and the entire outer can integrated with the cover plate function as the positive electrode of the unit cell 2, and the above-described nickel-aluminum clad plate 11 attached on the unit cell 2 functions as the positive electrode terminal. On the other hand, the negative electrode lead is electrically connected to, for example, a negative electrode terminal 12 (external terminal) attached to the cover plate via an insulating material.

  As shown in FIG. 7, the protection circuit board 3 includes a board 31 and a mounting component 32 that is mounted on the board 31 and constitutes the protection circuit of the unit cell 2. The protection circuit constituted by the mounting component 32 is a circuit for preventing the battery pack 1 from being overcharged or overdischarged.

  As shown in FIG. 7, the substrate 31 of the protection circuit board 3 is formed in a rectangular shape in plan view. Then, as shown in FIGS. 2 and 5, a positive electrode lead plate 33 and a conductive metal plate 34 are connected to the longitudinal end portion of the substrate 31, respectively. As shown in FIG. 2, the positive electrode lead plate 33 is electrically connected to a side surface located on the short side of the unit cell 2 when the unit cell 2 is viewed from the thickness direction.

  The protective element 35 has, for example, a configuration in which a molded body (temperature protective element) of a conductive polymer composition is sandwiched between two conductive metal plates 34, and is generally a PTC thermistor (Positive Temperature Coefficient). Thermistor) (refer to FIG. 7).

  Of the two conductive metal plates 34 connected to the molded body of the protection element 35, one conductive metal plate 34 is connected to the substrate 31 of the protection circuit substrate 3 as described above, and the other conductive metal plate 34 is connected to the other one. The conductive metal plate 34 is connected to the negative electrode lead plate 36 (see FIG. 5). As shown in FIG. 2, the negative electrode lead plate 36 is electrically connected to the negative electrode terminal 12 of the unit cell 2. Thereby, the protection circuit board 3 is electrically connected to the negative electrode terminal 12 via the protection element 35.

  As shown in FIGS. 2 and 5, one end of an output cable 37 is connected to the substrate 31 of the protection circuit substrate 3 on the surface opposite to the surface on which the circuit component 32 is mounted. The output cable 37 is a cable in which positive and negative output wirings and other output wirings are gathered, and an output connector 38 for connection to a device on which the battery pack 1 is mounted is provided on the other end side. . That is, the output connector 38 functions as an output terminal of the battery pack 1.

(Configuration of protection frame)
The protective frame 4 is made of a resin material such as polycarbonate. As shown in FIG. 3, the protective frame 4 is a member having a shape such that one side surface of a square tube is open, and has three wall portions 4a. In other words, the opening 4b is formed in the protective frame 4 by the three walls 4a. In addition, as shown in FIG. 3, in this embodiment, each wall part 4a is formed in the rectangular shape.

  Further, as shown in FIG. 2, the protection frame 4 can accommodate the protection circuit board 3 having the above-described configuration in the opening 4 b in a state where the surface direction of the board 31 coincides with the thickness direction of the unit cell 2. It is configured. That is, in the protective frame 4, the height in the opening direction of the opening 4 b in the pair of walls 4 a forming the opening 4 b is larger than the width (length in the short direction) of the substrate 31 of the protection circuit board 3. It is formed to be large. Thereby, the protection circuit board 3 can be disposed in the protection frame 4 so that the surface direction of the board 31 coincides with the thickness direction of the unit cell 2.

  Moreover, each wall part 4a of the protection frame 4 has a length equivalent to the length of the unit cell 2 in the longitudinal direction (vertical direction in the present embodiment). Further, the protective frame 4 is configured such that the height in the opening direction (the length in the drawing depth direction in FIGS. 2 and 3) is equal to the thickness of the unit cell 2. That is, the pair of wall portions 4a forming the opening 4b of the protective frame 4 has a height equivalent to the thickness of the unit cell 2 in the opening direction.

  As shown in FIGS. 2 and 5, the protective frame 4 has an opening 4 b in the thickness direction of the unit cell 2 on a side surface positioned in the longitudinal direction among the side surfaces extending in the thickness direction of the unit cell 2. It is attached as follows. That is, the protective frame 4 is positioned on the side surface of the pair of wall portions 4a forming the opening 4b, the one of the side walls 4a extending in the thickness direction of the unit cell 2 in the longitudinal direction. Yes. As described above, the negative electrode terminal 12 of the unit cell 2 is provided on the short side of the unit cell 2 when the unit cell 2 is viewed from the thickness direction. 12 is mounted on a different side. Thereby, as will be described later, the positive electrode lead plate 33 and the negative electrode lead plate 36 extending outward from the protective frame 4 can be easily connected to the unit cell 2 and the negative electrode terminal 12. The protective frame 4 is attached to the unit cell 2 with an adhesive tape 21.

  Thereby, since the impact applied to the side surface extending in the thickness direction of the battery pack 1 can be received by the wall portion 4a of the protective frame 4, the protective circuit board 3 in the protective frame 4 can be protected. The protective frame 4 has an opening 4b on one side in the thickness direction of the battery pack 1, but when an impact is applied in the thickness direction of the battery pack 1, the battery pack 1 is relatively wide. Since the force is received on the surface, a large force is not applied to the protection circuit board 3.

  As shown in FIGS. 2 and 3, among the wall portions 4 a of the protective frame 4, a plurality of wall portions 4 a that are attached to the side surfaces of the unit cells 2 protrude toward the inside of the protective frame 4 (this embodiment). In the case of the form, two) holding portions 4c are provided. These holding portions 4c are integrally formed with the wall portion 4a.

  In the present embodiment, a plurality of holding portions 4c are provided, but this is not restrictive, and only one holding portion 4c may be provided. Moreover, although the holding | maintenance part 4c is integrally formed in the wall part 4a, it is not restricted to this, You may form the holding | maintenance part 4c separately from the wall part 4a.

  As shown in FIG. 2, the holding part 4 c is configured such that the mounting component 32 mounted on the substrate 31 of the protection circuit board 3 is mounted on the wall part 4 a of the protection frame 4 in a state where the protection circuit board 3 is disposed in the protection frame 4. It has a protruding height capable of holding the substrate 31 so as not to come into contact with the substrate 31. That is, the holding portion 4 c has a protruding height that is larger than the thickness of the mounting component 32 mounted on the substrate 31. Thereby, even when an impact is applied to the battery pack 1, it is possible to prevent the mounting component 32 of the protection circuit board 3 from contacting the wall portion 4 a of the protection frame 4. Accordingly, it is possible to more reliably prevent the mounting component 32 of the protection circuit board 3 from being damaged in the protection frame 4.

  In the present embodiment, the holding portion 4c is formed on the wall portion 4a attached to the side surface of the unit cell 2. However, the present invention is not limited to this, and is opposite to the wall portion 4a attached to the side surface of the unit cell 2. A holding portion 4c may be provided on the wall portion 4a. In this case, the protection circuit board 3 may be arranged in the protection frame 4 so that the mounting surface of the board 31 on which the mounting component 32 is mounted is positioned on the holding portion 4c side.

(Battery pack manufacturing method)
Next, a method for manufacturing the battery pack 1 having the above-described configuration will be described with reference to FIGS.

  First, the unit cell 2 and the protective frame 4 are manufactured. Since the manufacturing method of the unit cell 2 is the same as that of the conventional battery, detailed description is omitted. Further, the protective frame 4 having the shape shown in FIG. 3 is formed by using injection molding or the like.

  Then, as shown in FIG. 4, the adhesive tape 21 is attached to one of the side surfaces extending in the thickness direction of the unit cell 2 when the unit cell 2 is viewed from the thickness direction. wear. At this time, the adhesive tape 21 is stuck on the side surface of the unit cell 2 so as to cover a part of the side surface located on the short side when the unit cell 2 is viewed from the thickness direction.

  The protective frame 4 is attached to the side surface of the long side of the unit cell 2 to which the adhesive tape 21 is attached. At this time, the outer side surface of the wall portion 4 a provided with the holding portion 4 c in the protective frame 4 is attached to the side surface on the long side of the unit cell 2.

  Thereafter, as shown in FIG. 5, the wiring unit 7 formed by connecting the output cable 37 and the protection element 35 to the protection circuit board 3 is inserted into the opening 4 b of the protection frame 4.

  Here, the manufacturing method of the wiring unit 7 is demonstrated using FIG. The positive electrode lead plate 33 and the conductive metal plate 34 of the protection element 35 are attached to the mounting surface of the mounting component 32 on the substrate 31 of the protection circuit 3 by welding. At this time, the positive electrode lead plate 33 and the conductive metal plate 34 are welded to the terminals 31a provided at both ends in the longitudinal direction of the substrate 31, respectively. In the protective element 35, a negative electrode lead plate 36 is attached to a conductive metal plate 34 that is not connected to the substrate 31 by welding.

  Then, the thickness direction of the positive electrode lead plate 33 and the negative electrode lead plate 36 (FIG. 7) is such that the respective leading end portions of the positive electrode lead plate 33 and the negative electrode lead plate 36 protrude toward the mounting surface side of the substrate 31 of the protection circuit board 3. Fold it toward the white arrow. Thereby, the positive electrode lead plate 33 and the negative electrode lead plate 36 are bent in the same direction (see FIG. 5).

  Further, the tip portion of the output cable 37 is fixed to the surface of the substrate 31 opposite to the mounting surface by soldering. The output cable 37 is electrically connected to an output terminal surface (not shown) formed on the substrate 31. Thereafter, the output cable 37 is formed into a crank shape as shown in FIG.

  Thereby, the wiring unit 7 having a shape as shown in FIG. 5 is obtained.

  The wiring unit 7 obtained as described above is inserted into the protective frame 4 attached to the unit cell 2 in the surface direction of the substrate 31 (see FIG. 5). Here, the wiring unit 7 is inserted until the substrate 31 hits the inner wall 4 a of the protective frame 4. Accordingly, as shown in FIG. 6, the protection circuit board 3 is accommodated in the protection frame 4 so that the wall 4 a covers the three sides. In this state, the positive electrode lead plate 33 of the wiring unit 7 is connected to the upper surface of the unit cell 2 by welding, while the negative electrode lead plate 36 is connected to the negative electrode terminal 12 by welding.

  Here, in the present embodiment, an example in which the tip portions of the positive electrode lead plate 33 and the negative electrode lead plate 36 are bent (see white arrows in FIG. 7) is shown. However, the present invention is not limited to this. For example, after the wiring unit 7 is inserted into the protective frame 4 before the tip portions of the positive electrode lead plate 33 and the negative electrode lead plate 36 are bent, the positive electrode lead plate 33 and the negative electrode lead plate 33 The tip portions of the lead plate 36 may be bent and the ends may be connected to the upper surface of the unit cell 2 and the negative electrode terminal 12.

  Although not shown in particular, by disposing the insulating plates 13 on the upper and lower surfaces of the unit cell 2 in the assembled state as shown in FIG. 6, the unit cell 2 and the protective frame 4 are covered with a heat shrinkable tube and heated. The outer tube 5 is formed. Thereafter, the label 6 is stuck on the outer tube 5 to obtain the battery pack 1 as shown in FIG.

  As described above, by attaching the protection frame 4 to the unit cell 2 so as to open in the thickness direction of the unit cell 2, the wiring unit 7 can be easily inserted into the protection frame 4. . Thereby, the wiring unit 7 can be easily attached to the protective frame 4 attached to the unit cell 2. Therefore, the assembly workability of the battery pack 1 can be improved.

  Moreover, by arranging the wiring unit 7 in the protective frame 4 as described above, the positive lead plate 33 of the wiring unit 7 is placed on the upper surface of the unit cell 2, and the negative lead plate 36 is placed on the negative terminal 12, respectively. Can be easily positioned. Thereby, the assembly workability | operativity of the battery pack 1 can further be improved.

(Effect of embodiment)
As described above, according to this embodiment, the protection frame 4 is attached to the side surface of the unit cell 2 so as to open in the thickness direction of the unit cell 2, and the protection circuit board 3 is disposed in the protection frame 4. Thereby, the protection circuit board 3 can be easily attached to the unit cell 2, and the protection circuit board 3 can be protected by the protection frame 4. Therefore, the battery pack 1 having high impact resistance can be configured in a simple and low-cost configuration in which the unit cell 2 and the protective frame 4 are covered with the outer tube 5.

  In addition, in the present embodiment, the protective circuit board 3 is inserted into the opening 4b of the protective frame 4 in the surface direction of the board 31, so that the strong shock received by the side surface extending in the thickness direction of the battery pack 1 is received. Can be received by. Thereby, the protection circuit board 3 can be protected from the impact which the battery pack 1 receives.

  Further, in the above-described configuration, the positive electrode lead plate 33 connected to the protection circuit board 3 and the negative electrode lead plate 36 connected to the protection circuit board 3 via the protection element 35 are bent, so that Can be easily positioned. Therefore, the positive electrode lead plate 33 and the negative electrode lead plate 36 can be easily connected to the unit cell 2 in a state where the protective circuit board 3 is disposed in the protective frame 4. Therefore, with the above-described configuration, the assembly workability of the battery pack 1 can be further improved.

  Further, the wall 4a of the protective frame 4 is provided with a holding portion 4c that protrudes inward so as to hold the protective circuit board 3, so that the battery pack 1 is protected when an impact is applied. It is possible to prevent the mounting component 32 mounted on the circuit board 3 from coming into contact with the wall portion 4 a of the protective frame 4.

(Other embodiments)
While the embodiments of the present invention have been described above, the above-described embodiments are merely examples for carrying out the present invention. Therefore, the present invention is not limited to the above-described embodiment, and the above-described embodiment can be appropriately modified and implemented without departing from the spirit of the invention.

  In the embodiment, the unit cell 2 and the protective frame 4 are covered with the exterior tube 5, but the present invention is not limited thereto, and the unit cell 2 and the protection frame 4 may be covered with an exterior label. That is, any configuration may be used as long as the unit cell 2 and the protective frame 4 are covered with the film member.

  In the embodiment, in the unit cell 2, the protective frame 4 is attached on the side surface of the unit cell 2 positioned in the longitudinal direction when the unit cell 2 is viewed from the thickness direction. However, when the unit cell 2 is viewed from the thickness direction, a protective frame may be attached on the side surface of the unit cell 2 positioned in the short direction.

  In the embodiment, the unit cell 2 is formed in a flat plate shape that is rectangular in plan view. However, the present invention is not limited to this, and any shape can be used as long as the electrode body can be accommodated therein. Also good.

  In the embodiment, the protective circuit board 3 is arranged in the protective frame 4 so that the surface direction of the board 31 coincides with the thickness direction of the unit cell 2. However, as shown in FIG. 8, the protection circuit board 3 may be arranged so that the thickness direction of the substrate 31 coincides with the thickness direction of the unit cell 2. Since the thickness of the battery pack can be reduced by such an arrangement, the arrangement as described above is preferably employed when the thickness of the unit cell 2 is small, for example. FIG. 8 is a diagram showing a partial cross section including the protective frame 50 in the cross section of the battery pack.

  Specifically, in the protective frame 50 having the wall portions 50a in three directions as in the above-described embodiment, the protruding portions 50c that protrude inward are formed on the pair of wall portions 50a that form the opening portions 50b. The protruding portion 50c is provided integrally with the wall portion 50a at a position where the pair of wall portions 50a face each other. Further, the protruding portion 50c is provided at a position inward of the protective frame 50 with respect to the protruding portion 50c and at a position so as to form a space in which the substrate 31 and the output cable 37 can be accommodated. It is formed so as to have a protruding height at which the mounting component 32 can be disposed between the portions 50c.

  With such a configuration, as shown in FIG. 8, with the substrate 31 and the output cable 37 disposed inside the protective frame 50 rather than the protrusion 50c, the substrate 31 is engaged with the opposing protrusion 50c. Can be made. Thereby, it is possible to prevent the mounting component 32 mounted on the substrate 31 from coming into contact with the wall portion 50 a of the protective frame 50. Therefore, even when an impact is applied to the battery pack, it is possible to prevent the mounting component 32 of the protection circuit board 3 from coming into contact with the protection frame 50 and being damaged.

  In addition, it is preferable that the protrusion part 50c provided in the wall part 50a of the protection frame 50 has the protrusion height and shape which can mount | wear with the protection circuit board 3 easily from the thickness direction of the unit cell 2. FIG.

  In the said embodiment, each wall part 4a of the protection frame 4 is formed in the rectangular shape. However, each wall portion may have any shape as long as it can form a space for accommodating the protection circuit board 3 and the protection element in the protection frame. For example, an opening may be formed in each wall portion, and the shape of each wall portion may be a shape other than a rectangular shape. Moreover, the wall part which connects a pair of opposing wall parts among three wall parts may be provided partially.

  In the embodiment, the protective frame 4 is attached to the unit cell 2 such that the opening 4 b opens in the thickness direction of the unit cell 2. However, the protective frame 4 may be attached to the unit cell 2 in any way as long as the opening 4b opens outward. However, it is preferable to provide a locking portion on the protective frame 4 so that the protective circuit board 3 does not come out of the protective frame 4 due to an impact received by the battery pack.

  In the embodiment, the nickel-aluminum clad plate attached to the outer can of the unit cell 2 is used as the positive electrode terminal. However, the present invention is not limited to this. For example, a positive electrode terminal as an external terminal is provided on the lid plate of the unit cell 2. May be. A plurality of positive terminals and negative terminals may be provided.

  In the said embodiment, the unit cell 2 is comprised as a lithium ion battery. However, the unit cell 2 may be a battery other than a lithium ion battery.

  The present invention can be used for a battery pack incorporated in a device.

1: battery pack, 2: unit cell, 3: protection circuit board, 4, 50: protection frame, 4a, 50a: wall, 4b, 50b: opening, 4c: holding part, 5: exterior tube (film member) 7: Wiring unit, 11: Positive terminal (external terminal), 12: Negative terminal (external terminal), 31: Substrate, 32: Mounted component, 50c: Protruding part (holding part)

Claims (7)

A unit cell having an external terminal;
A protective frame attached to the unit cell so as to have a wall in three directions so as to form an opening, and so that the opening opens outward,
A protective circuit board that is electrically connected to the external terminal and disposed in the opening of the protective frame;
A battery pack comprising: a film member that covers the unit cell and the protection frame so that the unit cell, the protection frame, and the protection circuit board are integrated. The battery pack according to claim 1,
The said protection frame is a battery pack attached to the said unit cell other than the part in which the said external terminal is provided. The battery pack according to claim 1 or 2,
The said protection circuit board is a battery pack arrange | positioned so that it may insert in the surface direction with respect to the said opening part in the said protection frame. The battery pack according to any one of claims 1 to 3,
A battery pack, wherein a wall portion of the protective frame is provided with a holding portion for holding the protective circuit board. The battery pack according to claim 4,
The protection circuit board includes a board and a mounting component mounted on the board,
The holding part is configured to protrude from the wall part to the inside of the protective frame so as to support the protective circuit board so that the mounting component does not contact the wall part of the protective frame. The battery pack according to claim 4,
The holding part is a battery pack that is a protruding part for locking the protective circuit board in the protective frame. The battery pack according to any one of claims 1 to 6,
The unit cell is formed in a flat plate shape having a large width dimension and a long dimension with respect to a thickness dimension,
The said protection frame is a battery pack attached to the side surface extended in the thickness direction of the said unit cell so that the said opening part may open in the thickness direction of the said unit cell.

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