Electronic apparatus, battery pack, and method for manufacturing battery pack

Abstract

An electronic apparatus according to one embodiment of the present disclosure comprises an apparatus body and a battery pack provided to the apparatus body. The battery pack includes: a battery cell; an exterior material wound around the battery cell; and a top cover and a bottom cover that seal the battery cell by being provided in openings in both ends of the exterior material so as to sandwich the battery cell around which the exterior material is wound.

Description

Electronic device, battery pack, and method of manufacturing the battery pack

[0001] The present disclosure relates to an electronic device, a battery pack, and a method for manufacturing a battery pack.

[0002] Various electronic devices, such as mobile phones (e.g., smartphones) and tablet computers, are known. These electronic devices use secondary batteries that can be repeatedly charged and discharged. Lithium-ion secondary batteries are widely used as one type of such secondary battery due to their various advantages, such as high voltage, high energy density, long cycle life, and rapid charging capability.

[0003] Lithium-ion secondary batteries are generally used in the form of a battery pack that incorporates battery cells, protection circuits, etc. A battery pack is formed by connecting a circuit board to the battery cells, wrapping a laminate sheet around the battery cells, and attaching a top cover and a bottom cover to the battery cells wrapped around the laminate sheet (see, for example, Patent Document 1).

[0004] JP 2019-160467 A

[0005] However, the top cover and bottom cover are sometimes fixed to the battery cells using, for example, a laminate sheet or adhesive. In this case, the rigidity of the battery pack may be insufficient, and the battery pack may not be able to withstand handling by users. For this reason, there is a demand for improving the rigidity of the battery pack.

[0006] Therefore, the present disclosure proposes an electronic device, a battery pack, and a method for manufacturing a battery pack that can improve the rigidity of the battery pack.

[0007] An electronic device according to one embodiment of the present disclosure includes a device main body and a battery pack provided in the device main body, the battery pack having a battery cell, an exterior material wrapped around the battery cell, and a top cover and a bottom cover provided in openings at both ends of the exterior material so as to sandwich the wrapped battery cell and seal the battery cell.

[0008] A battery pack according to one embodiment of the present disclosure includes a battery cell, an exterior material wrapped around the battery cell, and a top cover and a bottom cover provided at openings at both ends of the exterior material so as to sandwich the wrapped battery cell and seal the battery cell.

[0009] A manufacturing method of a battery pack according to one embodiment of the present disclosure includes wrapping an outer casing material around a battery cell, and providing a top cover and a bottom cover at openings at both ends of the outer casing material so as to sandwich the wrapped battery cell, thereby sealing the battery cell.

[0010] FIG. 1 is a perspective view showing an example of the appearance of a battery pack according to a first embodiment; FIG. 2 is an exploded perspective view showing an example of the configuration of a battery pack according to the first embodiment; FIG. 3 is a cross-sectional view showing an example of the configuration of a battery pack according to the first embodiment; FIG. 4 is a view showing a plan view and a bottom view of an example of the configuration of a battery pack according to the first embodiment; FIG. 5 is a view showing an example of the configuration of a battery pack of a comparative example according to the first embodiment; FIG. 6 is a cross-sectional view showing an example of the configuration of a battery pack according to a second embodiment; FIG. 7 is a view showing a plan view and a bottom view of an example of the configuration of a battery pack according to the second embodiment; FIG. 8 is a view showing a plan view and a bottom view of an example of the configuration of a battery pack of a modified example according to the second embodiment; FIG. 9 is a view for explaining an example of a manufacturing method of a battery pack according to the first or second embodiment; and FIG. 10 is a view showing an example of the configuration of an electronic device including a battery pack according to the first or second embodiment.

[0011] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The embodiments include examples and modifications. Note that the embodiments do not limit the electronic device, battery pack, and battery pack manufacturing method according to the present disclosure. In the following embodiments, the same reference numerals are used to designate essentially the same components, and redundant description will be omitted.

[0012] One or more of the following embodiments can be implemented independently. However, at least a portion of the following embodiments may be implemented in appropriate combination with at least a portion of another embodiment. These embodiments may include novel features that are different from one another. Therefore, each embodiment may contribute to solving different objectives or problems and may achieve different effects. The effects of each embodiment are merely examples and are not intended to be limiting, and other effects may also be achieved.

[0013] The present disclosure will be described in the following order: 1. First embodiment 1-1. Example of battery pack configuration 1-2. Comparative example 2. Second embodiment 2-1. Example of battery pack configuration 2-2. Modification 3. Manufacturing method of battery pack according to each embodiment 4. Application example of battery pack according to each embodiment 4-1. Example of electronic device configuration 5. Functions and effects according to each embodiment 6. Other embodiments 7. Supplementary notes

[0014] In this specification, for example, a structure including a battery element before being packaged in an exterior material is referred to as a battery cell, and a battery pack is a structure in which a circuit board is connected to a battery cell and an exterior material, a top cover, and a bottom cover are attached. In the battery pack, battery cell, and exterior material, the side from which the positive and negative terminals are led out is referred to as the top portion, the side opposite the top portion is referred to as the bottom portion, and the remaining portions are referred to as the side portions. Furthermore, the length in the direction of both side portions is sometimes referred to as the width, and the length in the direction from the top portion to the bottom portion is sometimes referred to as the height.

[0015] <1. First embodiment> <1-1. Configuration example of battery pack> A configuration example of a battery pack 10 according to this embodiment will be described with reference to Figs. 1 to 4. Fig. 1 is a perspective view showing an external appearance example of the battery pack 10 according to this embodiment. Fig. 2 is an exploded perspective view showing the configuration example of the battery pack 10 according to this embodiment. Fig. 3 is a cross-sectional view showing the configuration example of the battery pack 10 according to this embodiment. Fig. 4 is a view showing the top and bottom of the configuration example of the battery pack 10 according to this embodiment.

[0016] As shown in Fig. 1, the battery pack 10 is, for example, a device of a rectangular or flat lithium-ion secondary battery. The battery pack 10 is mounted, for example, in an electronic device. The electronic device may be configured so that the battery pack 10 cannot be detached by the user, or may be configured so that the battery pack 10 can be detached by the user. Examples of the electronic device include mobile phones such as smartphones, and personal computers such as tablet and notebook computers. The configuration of the electronic device will be described in detail later.

[0017] 2 and 3, the battery pack 10 includes a battery cell 20, a top cover 11, a bottom cover 12, a circuit board 40, and an exterior material 30. The top cover 11 may also be referred to as a top holder, and the bottom cover 12 may also be referred to as a bottom holder.

[0018] The battery cell 20 has a battery element covered with a laminate film such as a soft aluminum sheet. The battery element is electrically connected to a circuit board 40. An exterior material 30 is wrapped around and attached to the outer periphery of the battery cell 20. Openings are formed in both a top portion 31 and a bottom portion 32 (see FIG. 3 ) of the exterior material 30 wrapped around the battery cell 20. A top cover 11 is attached to the top portion 31, and a bottom cover 12 is attached to the bottom portion 32. The top portion 31 and the bottom portion 32 each function as an opening having an opening.

[0019] (Battery Cell) The battery cell 20 includes a battery element having a positive terminal 21a and a negative terminal 21b (see FIG. 2). The positive terminal 21a and the negative terminal 21b of this battery element are led out to one end of the battery element and are covered with an insulating sheet (not shown), for example, except for the portion connected to the circuit board 40. The battery cell 20 is formed in a thin plate shape, such as a flat type, to accommodate the miniaturization and thinning of electronic devices.

[0020] The battery element is, for example, a laminate in which a positive electrode, a separator, a negative electrode, and a separator are laminated in this order. This battery element may be a wound-type battery element in which a strip-shaped laminate is wound. A positive electrode terminal 21a is connected to the positive electrode of the battery element, and a negative electrode terminal 21b is connected to the negative electrode. Such a battery element is covered with a laminate film to form a battery cell 20. The laminate film, together with the battery element, is filled with an electrolyte. This battery element may be a known one.

[0021] 3 , the circuit board 40 is provided at an end of the battery cell 20, more specifically, on the top portion 31 of the exterior material 30 wrapped around the battery cell 20. The circuit board 40 is fixed to the battery cell 20 and the exterior material 30 by the top cover 11. The positive terminal 21 a and negative terminal 21 b of the battery element of the battery cell 20 are connected to the circuit board 40.

[0022] The circuit board 40 is mounted with connection terminals 41, a temperature detection element 42, and various elements 43 such as fuses and thermosensitive resistors. The circuit board 40 also has a first main surface M1 on the battery cell 20 side and a second main surface M2 on the opposite side from the battery cell 20 side. The temperature detection element 42 and various other elements 43 are provided on the first main surface M1. The connection terminals 41 are provided on the second main surface M2.

[0023] 3, the first principal surface M1 and the second principal surface M2 are parallel to the surface of the battery cell 20 on the first principal surface M1 side. Therefore, the circuit board 40 is parallel to the surface of the battery cell 20 on the first principal surface M1 side. In other words, the circuit board 40 is provided so as to be perpendicular to the planar direction of the battery cell 20 (e.g., the extension direction of the battery cell 20). Note that "parallel" includes both completely parallel and almost parallel, and "perpendicular" includes both completely perpendicular and almost perpendicular.

[0024] The connection terminal 41 is a terminal that is connected to a connection terminal on the device body of the electronic device. This connection terminal 41 is configured, for example, by a plurality of contacts or connectors. The connection terminal 41 is mounted, for example, at an end portion in the width direction of the circuit board 40 (see FIG. 2). The temperature detection element 42 is mounted, for example, at the center portion in the width direction of the circuit board 40. The various elements 43 are mounted, for example, at a portion other than the center portion in the width direction of the circuit board 40. The various elements 43 include, for example, a thermosensitive resistor element and a fuse.

[0025] A protection circuit including, for example, a temperature detection element 42 and various elements 43 is formed on the circuit board 40. The protection circuit includes, for example, a charge / discharge control field effect transistor (FET) (not shown), an integrated circuit (IC) (not shown) that monitors the secondary battery and controls the charge / discharge control FET, and the like.

[0026] The temperature detection element 42 is, for example, a thermistor, and its electrical resistance changes with changes in temperature of the temperature detection element 42. The protection circuit monitors the temperature detected by the temperature detection element 42, and if the detected temperature exceeds a preset threshold, it turns off the charge control FET to prohibit or suspend charging, or transmits temperature information to a charging circuit provided in the device main body to reduce the voltage during charging.

[0027] The thermosensitive resistor element is, for example, a PTC (Positive Temperature Coefficient) element and is connected in series with the battery element of the battery cell 20. When the temperature of the thermosensitive resistor element becomes higher than a set temperature, the electrical resistance of the thermosensitive resistor element increases rapidly, effectively cutting off the current flowing through the battery element. The fuse is connected in series with the battery element and, when an overcurrent flows through the battery element, melts down due to its own current, cutting off the current. In addition, a heater resistor is provided near the fuse, and when an overvoltage occurs, the temperature of the heater resistor rises, melting down and cutting off the current.

[0028] Furthermore, if the terminal voltage of the battery cell 20 becomes too high, it may cause heat generation or fire. For this reason, the protection circuit monitors the voltage of the battery cell 20, and if the voltage rises and an overcharge state occurs, it turns off the charge control FET to prohibit charging. Furthermore, if the terminal voltage of the battery cell 20 falls and the terminal voltage becomes 0 V due to an overdischarge state, the battery cell 20 may become internally shorted, making it impossible to recharge. For this reason, the protection circuit monitors the voltage of the battery cell 20, and if the battery cell 20 becomes overdischarged, it turns off the discharge control FET to prohibit discharging.

[0029] 3 , the top cover 11 is provided on the end of the battery cell 20, more specifically, on the top portion 31 of the exterior material 30 wrapped around the battery cell 20. The top cover 11 is a member that seals the battery cell 20 together with the exterior material 30 and the bottom cover 12. The top cover 11 is formed by filling the top portion 31 of the exterior material 30 wrapped around the battery cell 20 with a material for forming the top cover 11 (for example, a resin material), and is fixed to the battery cell 20 and the exterior material 30.

[0030] 3 , the entire surface of the top cover 11 on the battery cell 20 side is in contact with the battery cells 20. Note that it is sufficient if at least a part of the surface of the top cover 11 on the battery cell 20 side is in contact with the battery cells 20, but it is preferable that the entire surface of the top cover 11 on the battery cell 20 side be in contact with the battery cells 20 in order to fix the battery cells 20, etc.

[0031] The top cover 11 covers and seals the circuit board 40. For example, the top cover 11 contacts and covers almost the entire surface of the circuit board 40. However, the top cover 11 has openings 11a at positions corresponding to the connection terminals 41 of the circuit board 40 so that the connection terminals 41 are exposed to the outside. In other words, the top cover 11 covers the circuit board 40 while exposing the connection terminals 41 on the circuit board 40. The connection terminals 41 of the circuit board 40 contact connection terminals on the device body of the electronic device through the openings 11a in the top cover 11. This electrically connects the battery pack 10 to the device body.

[0032] As shown in Figures 3 and 4, the top cover 11 has multiple protrusions 11b and 11c. Each of the protrusions 11b and 11c is provided, for example, on both ends of the top surface of the top cover 11 and is rectangular in plan view (see Figure 4). These protrusions 11b and 11c function as fixing portions for fixing the battery pack 10 to the device body of the electronic device. The device body of the electronic device has recesses corresponding to the protrusions 11b and 11c of the top cover 11. The protrusions 11b and 11c of the top cover 11 are fitted into the recesses of the device body. Note that the protrusions 11b and 11c are omitted in the examples of Figures 1 and 2.

[0033] 3 , the bottom cover 12 is provided on the end of the battery cell 20, more specifically, on the bottom portion 32 of the exterior material 30 wrapped around the battery cell 20. The bottom cover 12 is a member that seals the battery cell 20 together with the exterior material 30 and the top cover 11. The bottom cover 12 is formed by filling the bottom portion 32 of the exterior material 30 wrapped around the battery cell 20 with a material for forming the bottom cover 12 (e.g., a resin material), and is fixed to the battery cell 20 and the exterior material 30.

[0034] 3 , the entire surface of the bottom cover 12 on the battery cell 20 side is in contact with the battery cells 20. Note that it is sufficient if at least a part of the surface of the bottom cover 12 on the battery cell 20 side is in contact with the battery cells 20, but for the purpose of fixing the battery cells 20, it is preferable that the entire surface of the bottom cover 12 on the battery cell 20 side be in contact with the battery cells 20.

[0035] As shown in Figures 3 and 4, the bottom cover 12 has a recess 12a. The recess 12a is formed, for example, in a rectangular shape in a plan view at the center of the bottom surface of the bottom cover 12 (see Figure 4). This recess 12a functions as a fixing portion for fixing the battery pack 10 to the device body of the electronic device. The device body of the electronic device has a protrusion formed thereon that corresponds to the recess 12a of the bottom cover 12. The recess 12a of the bottom cover 12 is fitted into the protrusion of the device body. The recess 12a of the bottom cover 12 fits into the device body, and the protrusions 11b and 11c of the top cover 11 fit into the device body, thereby fixing the battery pack 10 to the device body.

[0036] (Exterior Material) As shown in FIG. 2 , the exterior material 30 has a substantially rectangular shape and is attached to the battery cell 20 so as to encase the battery cell 20. The exterior material 30 is formed, for example, in a sheet shape. This exterior material 30 is attached to the periphery of the battery cell 20 via, for example, an adhesive layer. The exterior material 30 is a protective material for protecting the battery cell 20 and has higher strength than, for example, a resin laminate sheet. This allows it to protect the battery cell 20 from external impact. The exterior material 30 may be formed, for example, from hard aluminum or stainless steel, or may be formed as a laminate in which electrically insulating resin layers are laminated on both sides of a hard aluminum layer. The resin layers may be layers made of, for example, PET (Polyethylene Terephthalate) resin. The exterior material 30 has a thickness of, for example, about 0.1 mm, which is strong enough to withstand user handling.

[0037] <1-2. Comparative Example> A configuration example of a battery pack 10A as a comparative example according to the present embodiment will be described with reference to Fig. 5. Fig. 5 is a diagram showing a configuration example of a battery pack 10A as a comparative example according to the present embodiment. The battery pack 10A as the comparative example is a general built-in battery pack.

[0038] As shown in Figure 5, in the battery pack 10A of the comparative example, a flexible circuit board 51 is connected to the circuit board 40. The flexible circuit board 51 has a connector 52. The connector 52 is a component that connects to a connector on the device body side of the electronic device. The flexible circuit board 51 is connected to the device body of the electronic device via the connector 52. This flexible circuit board 51 is mounted, for example, on an end of the circuit board 40 in the width direction. The circuit board 40 is fixed to the battery cell 20 by an adhesive insulating sheet 53.

[0039] In the battery pack 10A of the comparative example, the battery cells 20 are exposed, and the method of fastening the circuit board 40 to the battery cells 20 is simply to wrap tape such as an adhesive insulating sheet 53 around the ends of the battery cells 20. The connector 52 requires connection work such as insertion and removal with the connector on the device main body. Furthermore, double-sided tape is generally used to fasten the battery pack 10A to the device main body, and dedicated tools (special tools) and specialized knowledge are required to attach and detach the battery pack 10A.

[0040] On the other hand, in the battery pack 10 according to this embodiment, the battery cells 20 are protected by the exterior material 30, and are further sandwiched between the top cover 11 and the bottom cover 12 and sealed in the internal space of the exterior material 30. As a result, the battery cells 20 are firmly joined to the exterior material 30 by the top cover 11 and the bottom cover 12. In addition, the circuit board 40 is firmly joined to the battery cells 20 and the exterior material 30 by the top cover 11. As a result, the rigidity of the battery pack 10 is increased, making it possible to provide a battery pack 10 that can withstand handling by a user.

[0041] Furthermore, the battery pack 10 has exposed connection terminals 41. This allows the battery pack 10 to be attached to the device body and the connection terminals 41 of the battery pack 10 to contact the connection terminals on the device body, eliminating the need for connecting the connector 52 to the device body. Furthermore, by using a hook structure, such as the protrusions 11b and 11c and the recesses 12a, to secure the battery pack 10 to the device body, special tools or specialized knowledge are not required for attaching or detaching the battery pack 10, making it easy to attach or detach the battery pack 10. In other words, by molding a convex or concave shape on the top cover 11 or the bottom cover 12 and providing a structure with the opposite shape on the device body, the battery pack 10 can be easily attached or detached.

[0042] In conventional removable battery packs using pouch-type cells, the exterior is typically a resin case with a certain degree of strength. The exterior of pouch-type cells is made of very thin, soft aluminum (O-type material), making it susceptible to damage. O-type material is aluminum that has been softened by annealing. Considering moldability, a resin case requires a wall thickness of 0.3 mm or more. The minimum wall thickness for flame retardancy varies depending on the resin material. For example, polycarbonate is often used as a case material, and one example is polycarbonate with a minimum wall thickness of 0.75 mm and a flame retardant grade of V-0 (UL standard). Considering moldability and flame retardancy, it is difficult to make a resin case thinner.

[0043] Therefore, for example, hard aluminum (H material) or stainless steel is used as the exterior material 30. In this case, the exterior material 30 can be strong enough to withstand user handling with a plate thickness of about 0.1 mm. H material is work-hardened aluminum. Also, compared to a resin case, a complex molding die is not required. Furthermore, printing can be done directly on the exterior material 30, eliminating the need for labels, etc. Also, since the exterior material 30 serves as a support during molding of the top cover 11 and bottom cover 12, molding of the top cover 11 and bottom cover 12 is facilitated.

[0044] 2. Second Embodiment 2-1. Configuration Example of Battery Pack An example configuration of the battery pack 10 according to this embodiment will be described with reference to Figs. 6 and 7. Fig. 6 is a cross-sectional view showing the configuration example of the battery pack 10 according to this embodiment. Fig. 7 is a diagram showing the top and bottom surfaces of the configuration example of the battery pack 10 according to this embodiment. Note that this embodiment is basically the same as the first embodiment, but differences will be described below.

[0045] As shown in Figures 6 and 7, in this embodiment, the top cover 11 has multiple protrusions 11d and 11e. Each of the protrusions 11d and 11e is provided, for example, on both ends of the top surface of the top cover 11 and has a rectangular shape in plan view (see Figure 7). Each of the protrusions 11d and 11e has a through-hole H1. For example, the through-hole H1 of the protrusion 11d is formed approximately at the center of the protrusion 11d in plan view, and the through-hole H1 of the protrusion 11e is formed approximately at the center of the protrusion 11e in plan view.

[0046] These protrusions 11d, 11e function as fixing portions for fixing the battery pack 10 to the device body of the electronic device. The device body of the electronic device has female threads formed therein that correspond to the through-holes H1 of the protrusions 11d, 11e. The recesses 12a of the bottom cover 12 are fitted into the protrusions of the device body, and the through-holes H1 of the protrusions 11d, 11e are aligned with the respective female threads of the device body, thereby attaching the battery pack 10 to the device body. Then, male screws are screwed into the respective female threads of the device body, and the battery pack 10 is fixed to the device body.

[0047] In addition, the inner surface of each through hole H1 of each convex portion 11d, 11e may be threaded to form a screw hole in both of each convex portion 11d, 11e, or the inner surface of the through hole H1 of one of each convex portion 11d, 11e may be threaded to form a screw hole in one of each convex portion 11d, 11e.

[0048] According to this embodiment, similar to the first embodiment, it is possible to improve the rigidity of the battery pack 10. Furthermore, similar to the first embodiment, no dedicated tool or specialized knowledge is required for attaching or detaching the battery pack 10, making it possible to easily attach or detach the battery pack 10.

[0049] <2-2. Modifications> A configuration example of a battery pack 10 according to a modification of the present embodiment will be described with reference to Fig. 8. Fig. 8 is a diagram showing a plan view and a bottom view of the configuration example of a battery pack 10 according to a modification of the present embodiment.

[0050] 8, in this modification, the bottom cover 12 has a protrusion 12b. The protrusion 12b is provided, for example, in the center of the bottom surface of the bottom cover 12 and is formed in a rectangular shape in a plan view. The protrusion 12b has a through-hole H1. For example, the through-hole H1 of the protrusion 12b is formed approximately in the center of the protrusion 12b in a plan view.

[0051] The protrusions 12b function as fixing parts for fixing the battery pack 10 to the device body of the electronic device. The device body of the electronic device has female threads formed therein that correspond to the through-holes H1 of the protrusions 12b. The through-holes H1 of the protrusions 12b of the bottom cover 12 and the through-holes H1 of the protrusions 11d and 11e are aligned with the female threads of the device body, and the battery pack 10 is attached to the device body. Then, male screws are threaded into the female threads of the device body, and the battery pack 10 is fixed to the device body.

[0052] According to the modified example, similar to the first embodiment, it is possible to improve the rigidity of the battery pack 10. Furthermore, similar to the first embodiment, no dedicated tool or specialized knowledge is required for attaching or detaching the battery pack 10, making it possible to easily attach and detach the battery pack 10.

[0053] In the above-described embodiments (including modified examples), any one of the convex portions 11b, 11c, 11d, 11e, and 12b and the concave portion 12a is provided on both the top cover 11 and the bottom cover 12, but for example, they may be provided on only one of the top cover 11 and the bottom cover 12. Furthermore, the number of any one of the convex portions 11b, 11c, 11d, 11e, and 12b and the concave portion 12a may be one or more, and the installation positions of any one of the convex portions 11b, 11c, 11d, 11e, and 12b and the concave portion 12a are not limited.

[0054] 3. Manufacturing Method of Battery Pack According to Each Embodiment A manufacturing method of the battery pack 10 according to each embodiment will be described with reference to Fig. 9. Fig. 9 is a diagram for explaining an example of a manufacturing method of the battery pack 10 according to each embodiment. In the example of Fig. 9, components other than the battery cells 20 and the exterior material 30 (e.g., circuit board 40, etc.) are omitted.

[0055] As shown in Figure 9, one example of a manufacturing method uses a mold 61 for injection molding. Injection molding (molding) is a method in which heated and melted material is injected from a cylinder or the like into the mold 61 to fill it, and then cooled and solidified to form a mold. Injection molding makes it possible to realize low-temperature resin molding.

[0056] The mold 61 may be used in common for molding the top cover 11 and the bottom cover 12, or may be prepared separately for molding the top cover 11 and the bottom cover 12. For example, even if the mold 61 is used in common for molding the top cover 11 and the bottom cover 12, other mold parts may be added to or removed from the mold 61 as needed for each molding of the top cover 11 and the bottom cover 12.

[0057] In the manufacturing process of the battery pack 10, the exterior material 30 is wrapped around the battery cell 20, and the battery cell 20 wrapped with the exterior material 30 is prepared. The end of the battery cell 20 wrapped with the exterior material 30 is inserted into a mold 61. Specifically, the top portion 31 of the exterior material 30 wrapped around the battery cell 20 is inserted into the mold 61. Next, a resin material (an example of a material for forming the top cover 11) that has been melted by heating is injected into the mold 61, and the resin material fills the top portion 31 of the exterior material 30. The filled resin material is then cooled and solidified. As a result, the top cover 11 having a shape based on the mold 61 is formed on the top portion 31 of the exterior material 30. At this time, the top cover 11 is firmly attached to the battery cell 20, the circuit board 40, and the exterior material 30, firmly joining the battery cell 20, the circuit board 40, and the exterior material 30.

[0058] Next, the bottom portion 32 of the exterior material 30 wrapped around the battery cells 20 is inserted into a mold 61. Next, a resin material (one example of a material for forming the bottom cover 12) that has been heated and melted is injected into the mold 61, filling the bottom portion 32 of the exterior material 30 with the resin material. The filled resin material is then cooled and hardened. As a result, a bottom cover 12 having a shape based on the mold 61 is formed on the bottom portion 32 of the exterior material 30. At this time, the bottom cover 12 is fixed to the battery cells 20, circuit board 40, and exterior material 30, firmly joining the battery cells 20, circuit board 40, and exterior material 30.

[0059] The top cover 11 and the bottom cover 12 are formed by filling the resin in this manner. This integrates the battery cells 20, the circuit board 40, and the exterior material 30, improving the rigidity of the battery pack 10 and providing the battery pack 10 with a rigidity that can withstand handling by a user. For example, the battery pack 10 has a strength that can withstand an impact such as when the user accidentally drops the battery pack 10. Furthermore, the exterior material 30 serves as a support when molding the top cover 11 and the bottom cover 12, making it easier to mold the top cover 11 and the bottom cover 12.

[0060] In the above description, the top cover 11 is formed before the bottom cover 12, but conversely, the bottom cover 12 may be formed before the top cover 11, or the top cover 11 and the bottom cover 12 may be formed simultaneously. Furthermore, the top cover 11 and the bottom cover 12 may be formed from the same material, or may be formed from different materials.

[0061] <4. Application Examples of Battery Packs According to Each Embodiment> <4-1. Configuration Example of Electronic Device> A configuration example of an electronic device 100 including a battery pack 10 according to any of the above-described embodiments will be described with reference to Fig. 10. Fig. 10 is a diagram showing a configuration example of an electronic device 100 including a battery pack 10 according to any of the above-described embodiments.

[0062] As shown in FIG. 10, the electronic device 100 includes a device main body 101, an electronic circuit 102, and a battery pack 10.

[0063] The device main body 101 is a housing that houses the electronic circuit 102, the battery pack 10, etc. The electronic circuit 102 controls the entire electronic device 100. The electronic circuit 102 includes, for example, a CPU (Central Processing Unit), a peripheral logic unit, an interface unit, a memory unit, etc.

[0064] As described above, the battery pack 10 includes the battery cells 20, the circuit board 40, and the like, and is electrically connected to the electronic circuit 102 via the connection terminals 41. In the example of Fig. 10, the connection terminals 41 include a positive terminal 41a, a negative terminal 41b, and a temperature terminal 41c. Gold-plated terminals, for example, can be used as the positive terminal 41a, the negative terminal 41b, and the temperature terminal 41c.

[0065] The battery pack 10 is configured, for example, to be detachable from the device main body 101 by the user. The battery pack 10 may also be configured not to be detachable from the device main body 101 by the user.

[0066] When the battery pack 10 is attached to the device body 101, the positive terminal 41 a, the negative terminal 41 b, and the temperature terminal 41 c of the battery pack 10 are connected to the positive terminal, the negative terminal, and the temperature terminal of the electronic circuit 102 of the device body 101, respectively. The battery pack 10 is charged, for example, while attached to the device body 101.

[0067] However, if the battery pack 10 is detachable from the device body 101 by the user, for example, the battery pack 10 may be removed from the device body 101 and attached to a charger to charge the battery pack 10. At this time, the positive terminal 41a, negative terminal 41b, and temperature terminal 41c of the battery pack 10 are connected to the positive terminal, negative terminal, and temperature terminal of the charger.

[0068] By applying a battery pack 10 according to any of the above-described embodiments to an electronic device 100 configured in this manner, it is possible to provide an electronic device 100 equipped with a battery pack 10 having high rigidity that can withstand handling by a user.

[0069] The electronic device 100 may be a portable electronic device or a non-portable electronic device. Examples of the electronic device 100 include, but are not limited to, mobile phones such as smartphones, tablet or notebook personal computers, personal digital assistants (PDAs), digital still cameras, video cameras, wearable devices, game devices, music devices, e-books, electronic dictionaries, display devices, and navigation systems.

[0070] 5. Functions and Effects of Each Embodiment As described above, according to each embodiment, the electronic device 100 includes a device main body 101 and a battery pack 10 provided in the device main body 101. The battery pack 10 includes battery cells 20, an exterior material 30 wrapped around the battery cells 20, and a top cover 11 and a bottom cover 12 that are provided in openings (e.g., top portion 31 and bottom portion 32) at both ends of the exterior material 30 so as to sandwich the wrapped battery cells 20 (see FIGS. 1 to 4 , etc.). As a result, the battery cells 20 are sandwiched between the top cover 11 and the bottom cover 12 and sealed in the internal space of the exterior material 30, and are firmly joined to the exterior material 30 by the top cover 11 and the bottom cover 12. This improves the rigidity of the battery pack 10.

[0071] The top cover 11 and the bottom cover 12 may be formed by filling openings at both ends of the exterior material 30 (e.g., the top portion 31 and the bottom portion 32) with a resin material (see FIG. 3 ). This can reliably improve the rigidity of the battery pack 10.

[0072] Furthermore, the surface of the top cover 11 facing the battery cells 20 and the surface of the bottom cover 12 facing the battery cells 20 may be in contact with the battery cells 20 (see FIG. 3 ). This can reliably improve the rigidity of the battery pack 10.

[0073] Furthermore, the entire surface of the top cover 11 facing the battery cells 20 and the entire surface of the bottom cover 12 facing the battery cells 20 may be in contact with the battery cells 20 (see FIG. 3 ). This makes it possible to more reliably improve the rigidity of the battery pack 10.

[0074] The battery pack 10 may further include a circuit board 40 electrically connected to the battery cells 20, and the top cover 11 may cover and seal the circuit board 40 (see FIG. 3 ). This allows the circuit board 40 to be firmly joined to the battery cells 20 and the exterior material 30 by the top cover 11, thereby reliably improving the rigidity of the battery pack 10.

[0075] Furthermore, the circuit board 40 may have connection terminals 41 to be connected to the device body 101, and the top cover 11 may cover the circuit board 40, leaving the connection terminals 41 exposed (see FIG. 3 ). This allows the battery pack 10 to be electrically connected to the device body 101 by simply attaching the battery pack 10 to the device body 101 and bringing the connection terminals 41 of the battery pack 10 into contact with connection terminals on the device body 101, thereby eliminating the need for a cumbersome connection process and facilitating attachment and detachment of the battery pack 10.

[0076] The circuit board 40 may have a first main surface M1 on the battery cell 20 side and a second main surface M2 opposite the first main surface M1, and the connection terminals 41 may be provided on the second main surface M2 (see FIG. 3 ). This allows the connection terminals 41 to be easily exposed from the top cover 11.

[0077] Furthermore, the first principal surface M1 and the second principal surface M2 may be parallel to the surface of the battery cell 20 on the first principal surface M1 side (see FIG. 3 ). This makes the circuit board 40 parallel to the surface of the battery cell 20 on the first principal surface M1 side, allowing the battery pack 10 to be more compact than when the circuit board 40 is perpendicular to the surface of the battery cell 20 on the first principal surface M1 side.

[0078] The top cover 11 may also have protrusions (e.g., protrusions 11b and 11c) or recesses (e.g., recess 12a) for fixing the battery pack 10 to the device body 101 (see FIGS. 3 and 4). This allows the battery pack 10 to be easily fixed to the device body 101, eliminating the need for dedicated tools or specialized knowledge for attaching and detaching the battery pack 10, and facilitating the attachment and detachment of the battery pack 10.

[0079] The top cover 11 also has the aforementioned protrusions (e.g., protrusions 11d and 11e), which may have through-holes H1 (see FIGS. 6 to 8). This allows the battery pack 10 to be easily fixed to the device body 101, eliminating the need for specialized tools or specialized knowledge for attaching and detaching the battery pack 10, and facilitating the attachment and detachment of the battery pack 10.

[0080] The bottom cover 12 may also have a protrusion (e.g., protrusion 12b) or a recess (e.g., recess 12a) for fixing the battery pack 10 to the device body 101 (see FIGS. 3, 4, 7, and 8). This allows the battery pack 10 to be easily fixed to the device body 101, eliminating the need for dedicated tools or specialized knowledge for attaching and detaching the battery pack 10, and facilitating the attachment and detachment of the battery pack 10.

[0081] The bottom cover 12 also has the aforementioned protrusion (for example, protrusion 12b), which may have a through-hole H1 (see FIG. 8 ). This allows the battery pack 10 to be easily fixed to the device body 101, eliminating the need for specialized tools or specialized knowledge for attaching and detaching the battery pack 10, and facilitating the attachment and detachment of the battery pack 10.

[0082] The exterior material 30 may also be made of hard aluminum (see FIGS. 2 and 3), which allows the exterior material 30 to have sufficient strength to withstand handling by a user.

[0083] 6. Other Embodiments The configurations and processes according to the above-described embodiments (including examples and modified examples) may be implemented in various different forms other than the above-described embodiments. For example, the configurations and processes are not limited to the above-described examples and may be implemented in various forms. Furthermore, for example, the configurations, processing procedures, specific names, or information including various data and parameters shown in the above documents and drawings may be changed arbitrarily unless otherwise specified.

[0084] Furthermore, the components and processes according to the above-described embodiments (including examples and modifications) do not necessarily have to be physically configured as shown in the drawings. In other words, the specific form of distribution and integration of the components and processes is not limited to that shown in the drawings, and all or part of them may be functionally or physically distributed or integrated in any unit depending on various loads, usage conditions, etc.

[0085] Furthermore, the configurations and processes of the above-described embodiments (including examples and modified examples) may be combined as appropriate. For example, at least a part of an embodiment may be combined as appropriate with at least a part of another embodiment. Furthermore, the effects of the embodiments are merely examples and are not intended to be limiting, and other effects may also be obtained.

[0086] <7. Supplementary Notes> The present technology can also be configured as follows. (1) An electronic device comprising: a device main body; and a battery pack provided in the device main body, wherein the battery pack has: a battery cell; an exterior material wrapped around the battery cell; and a top cover and a bottom cover that are provided in openings at both ends of the exterior material so as to sandwich the wrapped battery cell and seal the battery cell. (2) The electronic device according to (1), wherein the top cover and the bottom cover are formed by filling the openings at both ends of the exterior material with a resin material. (3) The electronic device according to (1) or (2), wherein a surface of the top cover facing the battery cell and a surface of the bottom cover facing the battery cell are in contact with the battery cell. (4) The electronic device according to (3), wherein the entire surface of the top cover facing the battery cell and the entire surface of the bottom cover facing the battery cell are in contact with the battery cell. (5) The electronic device according to any one of (1) to (4), wherein the battery pack further includes a circuit board electrically connected to the battery cells, and the top cover covers and seals the circuit board. (6) The electronic device according to (5), wherein the circuit board has connection terminals connected to the device main body, and the top cover covers the circuit board with the connection terminals exposed. (7) The electronic device according to (6), wherein the circuit board has a first main surface facing the battery cells and a second main surface opposite the first main surface, and the connection terminals are provided on the second main surface. (8) The electronic device according to (7), wherein the first main surface and the second main surface are parallel to a surface of the battery cell facing the first main surface. (9) The electronic device according to any one of (1) to (8), wherein the top cover has a protrusion or a recess for fixing the battery pack to the device main body. (10) The electronic device according to (9), wherein the top cover has the protrusion, and the protrusion has a through-hole.(11) The electronic device according to any one of (1) to (10), wherein the bottom cover has a protrusion or a recess for fixing the battery pack to the device body. (12) The electronic device according to (11), wherein the bottom cover has the protrusion, and the protrusion has a through-hole. (13) The electronic device according to any one of (1) to (12), wherein the exterior material is formed of hard aluminum. (14) A battery pack comprising: a battery cell; an exterior material wrapped around the battery cell; and a top cover and a bottom cover provided in openings at both ends of the exterior material so as to sandwich the battery cell around which the exterior material is wrapped, and sealing the battery cell. (15) A method for manufacturing a battery pack, comprising: wrapping an exterior material around a battery cell; and providing a top cover and a bottom cover in openings at both ends of the exterior material so as to sandwich the battery cell around which the exterior material is wrapped, and sealing the battery cell. (16) A battery pack included in the electronic device according to any one of (1) to (13). (17) A battery pack manufacturing method for manufacturing a battery pack included in the electronic device according to any one of (1) to (13).

[0087] REFERENCE SIGNS LIST 10 Battery pack 10A Battery pack 11 Top cover 11a Opening 11b Convex portion 11c Convex portion 11d Convex portion 11e Convex portion 12 Bottom cover 12a Concave portion 12b Convex portion 20 Battery cell 21a Positive electrode terminal 21b Negative electrode terminal 30 Exterior material 31 Top portion 32 Bottom portion 40 Circuit board 41 Connection terminal 41a Positive electrode terminal 41b Negative electrode terminal 41c Temperature terminal 42 Temperature detection element 43 Various elements 51 Flexible circuit board 52 Connector 53 Adhesive insulating sheet 61 Mold 100 Electronic device 101 Device body 102 Electronic circuit H1 Through hole M1 First main surface M2 Second main surface

Claims

1. An electronic device comprising: a device body; and a battery pack provided in the device body, wherein the battery pack has a battery cell; an exterior material wrapped around the battery cell; and a top cover and a bottom cover that are provided in openings at both ends of the exterior material so as to sandwich the wrapped battery cell, and that seal the battery cell.

2. The electronic device according to claim 1, wherein the top cover and the bottom cover are formed by filling the openings at both ends of the exterior material with a resin material.

3. The electronic device according to claim 1, wherein a surface of the top cover facing the battery cell and a surface of the bottom cover facing the battery cell are in contact with the battery cell.

4. The electronic device according to claim 3, wherein the entire surface of the top cover facing the battery cell and the entire surface of the bottom cover facing the battery cell are in contact with the battery cell.

5. The electronic device according to claim 1, wherein the battery pack further comprises a circuit board electrically connected to the battery cells, and the top cover covers and seals the circuit board.

6. The electronic device according to claim 5, wherein the circuit board has connection terminals connected to the main body of the device, and the top cover covers the circuit board while leaving the connection terminals exposed.

7. The electronic device according to claim 6, wherein the circuit board has a first main surface on the side of the battery cell and a second main surface opposite the first main surface, and the connection terminal is provided on the second main surface.

8. The electronic device according to claim 7, wherein the first principal surface and the second principal surface are parallel to a surface of the battery cell on the first principal surface side.

9. The electronic device according to claim 1, wherein the top cover has a protrusion or recess for fixing the battery pack to the device body.

10. The electronic device according to claim 9, wherein the top cover has a protrusion, and the protrusion has a through hole.

11. The electronic device according to claim 1, wherein the bottom cover has a protrusion or recess for fixing the battery pack to the device body.

12. The electronic device according to claim 11, wherein the bottom cover has the protrusion, and the protrusion has a through hole.

13. The electronic device according to claim 1, wherein the exterior material is made of hard aluminum.

14. A battery pack comprising: a battery cell; an exterior material wrapped around the battery cell; and a top cover and a bottom cover provided at openings at both ends of the exterior material so as to sandwich the wrapped battery cell and seal the battery cell.

15. A method for manufacturing a battery pack, comprising: wrapping an outer casing around a battery cell; and providing a top cover and a bottom cover at openings at both ends of the outer casing so as to sandwich the battery cell wrapped in the outer casing, thereby sealing the battery cell.