JP2014053145A - Mobile speech communication device battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mobile speech communication device battery pack, capable of shielding additional electromagnetic field induced externally which is generated from a mobile speech communication device.SOLUTION: A mobile speech communication device battery pack 1 housed in a housing section 104 disposed on a back face section of an enclosure 110 constituting a mobile speech communication device 100, includes: a unit cell 30; and a magnetic sheet 40. In a state where the mobile speech communication device battery pack 1 is housed in the housing part 104, the magnetic sheet 40 is disposed on a device 100 side of the unit cell 30 as a member for shielding an electromagnetic field occurred in the device 100 side of the unit cell 30 which is generated from the unit cell.

Description

  The present invention relates to a battery pack for mobile phone devices.

In mobile phone devices, strict regulations are taken to prevent electromagnetic waves radiated during communication from affecting human bodies and malfunctioning of electronic devices attached to human bodies such as hearing aids and pacemakers.
In order to cope with the above-mentioned regulations regarding electromagnetic waves, not only the device main body of the mobile phone device but also the housing portion that houses the battery pack provided on the back surface of the mobile phone device casing is radiated from the housing portion. It has been proposed to take shielding means against electromagnetic waves (Patent Document 1).

  In Patent Document 1, electromagnetic waves radiated from the device main body part may leak into the housing part via the external terminal and amplify the external terminal as an antenna, and also shield the area near the external terminal constituting the battery pack. It is pointed out that this is a source of electromagnetic waves that should be. And the technique of shielding the radiation of the electromagnetic wave from an accommodating part by providing a magnetic sheet on the connection wiring which the external terminal of a battery pack joins is shown.

JP 2004-103248 A

However, Patent Document 1 focuses on electromagnetic waves radiated to the outside from the accommodating portion of the mobile phone, but there is no suggestion about the viewpoint of shielding the electromagnetic field induced by the battery pack itself, and shielding means therefor Has not been studied.
Regarding electromagnetic fields induced externally from mobile phone devices, not only electromagnetic waves but also electrostatic magnetic fields are only relevant to the effect on the human body, and it is in accordance with social demands to shield as much as possible. . Therefore, it is not necessary to handle the battery pack exceptionally.
Moreover, the weight and volume energy density of the secondary battery according to the battery pack are improved in response to the reduction in weight and thickness of the battery pack accommodated in the mobile telephone device. In light of this situation, it can be said that it is an urgent technical issue to examine shielding means for the electromagnetic field generated by the secondary battery during charging and discharging of the battery pack.
The present invention has been made in view of the above problems, and provides a battery pack for a mobile phone device that can further shield an electromagnetic field induced outside using the mobile phone device as a generation source. For the purpose.

  Therefore, the present invention relates to a mobile phone device battery pack (hereinafter also referred to as a “battery pack”) accommodated in a housing portion provided on a back surface portion of a mobile phone device case. And a magnetic sheet, and in the storage state in the storage portion, the magnetic sheet serves as a member for shielding an electromagnetic field generated on the device side of the unit cell using the unit cell as a generation source. It is arranged on the side.

  In the battery pack for mobile phone devices according to the present invention, in a state where the battery pack is housed in the housing portion, the magnetic sheet is the device side of the unit cell, that is, the surface of the unit cell facing the device (hereinafter referred to as “device side surface”) It is provided in any part between the device side surface and the bottom surface of the accommodating portion, which is above or above the device side surface. For this reason, the magnetic field which a unit cell induces according to charging / discharging of a unit cell will be bent toward the magnetic sheet. As a result, the magnetic field intensity above the device side surface of the unit cell can be reduced. In other words, in the state where the battery pack is housed in the housing portion provided on the back surface portion of the mobile phone case, the front side of the mobile phone having the receiving portion is provided above the device side surface of the unit cell. Although it is located, it is possible to reduce the magnitude of the electromagnetic field induced on the receiver side of the portable telephone device using the unit cell as a generation source.

For example, the following variations can be employed in the battery pack for mobile phone devices according to the present invention.
In the battery pack for portable telephone equipment according to the present invention, the unit cell includes an electrode body that is wound in a state in which a positive electrode element and a negative electrode element are arranged to face each other via a separator.
As the structure of the electrode body, a wound type structure and a laminated type structure can be adopted from the viewpoints of high energy density and thinning, but the wound type structure is excellent from the viewpoint of mass productivity. . When the structure of the electrode body is a wound structure, it can be said that the magnetic field strength related to the magnetic field using the unit cell as a generation source is increased as in the case of the stacked structure. Therefore, it is particularly useful to use a battery pack provided with the magnetic sheet according to the present invention.

In the battery pack for a portable telephone device according to the present invention, the unit cell has a flat rectangular shape, and the magnetic sheet is in the unit side of the pair of wide surfaces of the unit cell when stored in the storage unit. The battery is disposed on the first main surface of the battery or at any portion above the first main surface of the battery.
As the external shape of the unit cell, those having a cylindrical shape or a rectangular shape can be adopted, but those having a flat rectangular shape are excellent in consideration of the reduction in the thickness of the mobile phone. When adopting a unit cell having a flat rectangular shape, a position where the battery first main surface located on the device side of the pair of wide surfaces of the unit cell faces the bottom surface of the storage unit in the storage state in the storage unit It becomes a relationship. Since the battery first main surface has a relatively large area, it can be said that the magnetic field intensity generated above the battery first main surface also increases. Therefore, it is particularly useful to use a battery pack provided with the magnetic sheet according to the present invention.

In the battery pack for portable communication devices according to the present invention, the unit cell is packaged, the package further includes an outer package having a flat rectangular shape, and the magnetic sheet is a first wide surface of the unit cell, or a pair of wide outer packages. Among the surfaces, it is arranged on at least one main surface of the exterior first main surface located on the battery first main surface side.
When the external shape of the unit cell has a flat rectangular shape and a configuration including an exterior body that covers the unit cell is employed, the exterior of the exterior body has a flat rectangular shape corresponding to the external appearance of the unit cell. Is done. Therefore, by providing a magnetic sheet on the exterior first main surface located on the battery first main surface side of the pair of wide surfaces of the exterior body, the unit cell is induced on the receiver side of the portable telephone device as a generation source. The magnitude of the electromagnetic field can be reduced. Here, the first main surface of the battery or the first main surface of the exterior is relatively flat and has a large area as compared with the surfaces of the other components. Therefore, by adopting a configuration in which the magnetic sheet is provided on at least one main surface of the battery first main surface or the exterior first main surface, the magnetic sheet is prevented from being bent on the arrangement surface, and the magnetic field The effect of reducing the strength can be favorably expressed.

Further, when adopting a configuration including an exterior label as the configuration of the exterior body, since the exterior label is usually composed of a resin material, the magnetic sheet is easily integrated on the exterior label using a known printing method. By forming the magnetic sheet, it is possible to simplify the work and arrangement of the magnetic sheet.
In the battery pack for mobile phone devices according to the present invention, the magnetic sheet is disposed on the central region of the battery first main surface or the exterior first main surface.

  As long as the magnetic sheet is configured to cover the battery first main surface, the arrangement position is not particularly limited. However, according to the verification result described later, the configuration is such that only the battery first main surface is covered. A significant electromagnetic field shielding effect can be obtained by covering only the central region of the main surface. Therefore, by adopting a configuration in which a magnetic sheet is provided on the central region of the battery first main surface or the exterior first main surface, the thickness of the battery pack can be reduced, the cost can be reduced, and the magnetic field strength can be reduced. Can be expressed well.

In the battery pack for portable telephone equipment according to the present invention, the magnetic sheet is made of a magnetic metal material made of a Co-based amorphous alloy.
The type of the magnetic material constituting the magnetic sheet is not particularly limited, but the effect of reducing the magnetic field strength can be further exhibited by employing a magnetic material having a higher magnetic permeability. Also, when thinning the battery pack, the thickness of the magnetic sheet is in the order of microns. Therefore, by adopting a magnetic material with excellent mechanical strength, the magnetic sheet strength is maintained and the magnetic field strength is reduced. Can be expressed more. Specifically, by adopting an amorphous alloy, particularly a Co-based amorphous alloy, the effect of reducing the magnetic field strength by the magnetic sheet can be expressed more favorably.

In the battery pack for portable telephone equipment according to the present invention, the unit cell is a lithium ion secondary battery.
The type of battery material used for the unit cell is not limited. However, when a lithium ion secondary battery that is superior to other battery materials in terms of weight and volume energy density is adopted, it depends on the magnetic field that uses the unit cell as a source. It can be said that the magnetic field intensity also increases. Therefore, it is particularly useful to use a battery pack provided with the magnetic sheet according to the present invention.

1 is a perspective view showing an external appearance of a battery pack 1 for a mobile phone device according to Embodiment 1. FIG. (A) is a front view which illustrates the portable telephone apparatus in which the battery pack 1 for portable telephone devices is accommodated, (b) is the back perspective view of the portable telephone apparatus which shows the accommodation process of the battery pack 1 for portable telephone devices. FIG. 3C is a cross-sectional view of the portable telephone device showing the accommodation state of the portable telephone device battery pack 1 as seen from the side. It is a perspective view which shows the external appearance of the core pack 20 with which the battery pack 1 for portable telephone devices is provided. 3 is a developed perspective view showing a configuration of a core pack 20. FIG. (A) is a partially cutaway perspective view showing the configuration of the unit cell 30 provided in the battery pack 1 for portable telephone equipment, and (b) is a perspective view showing the configuration of the electrode body 34 provided in the unit cell 30. is there. (A) is a figure which shows typically the electric field in the inside of the unit cell 30, (b) is a figure which shows typically the magnetic field which the unit cell 30 induces, (c) is the magnetic sheet 40. It is a figure which shows the function of no. It is the perspective view which shows the external appearance of the battery pack 5 for portable telephone apparatuses which concerns on Embodiment 2, and sectional drawing which expands and shows the principal part. It is an expansion | deployment perspective view which shows the internal structure in the battery pack 5 for portable telephone devices. (A), (b), (c) is a figure which shows the arrangement | positioning form of the magnetic sheet 40 used for each verification experiment, (d) is a figure which shows the measurement position of a verification experiment. (A), (b), (c) shows the change of the magnetic field intensity in the X-axis, Y-axis, and Z-axis directions, respectively, obtained by the magnetic force measurement in the arrangement form of each magnetic sheet 40 shown in FIG. It is an experimental result. (A), (b) is a figure which shows the arrangement | positioning form of the magnetic sheet 40 used for each verification experiment. (A), (b), (c) are the magnetic field strengths in the X-axis, Y-axis, and Z-axis directions, respectively, obtained by magnetic force measurement in the arrangement of the magnetic sheets 40 shown in FIG. It is an experimental result which shows a change. (A), (b), and (c) are the magnetic field strengths in the X-axis, Y-axis, and Z-axis directions, respectively, obtained by magnetic force measurement in the arrangement form of each magnetic sheet 40 shown in FIG. It is an experimental result which shows a change. It is a disassembled perspective view which shows the structure of the battery pack 90 for portable telephone apparatuses which concerns on a modification.

Below, the form for implementing this invention is demonstrated. The embodiment used in the following description is an example used to explain the configuration, operation, and effect of the present invention in an easy-to-understand manner, and the present invention is not limited to the following form other than its essential part. It is not something to receive.
[Embodiment 1]
1. External Configuration of Battery Pack for Mobile Phone Device As shown in FIG. 1, the external appearance of the battery pack for mobile phone device (hereinafter also referred to as “battery pack”) 1 according to Embodiment 1 is a shallow dish-shaped bottom case 12. And the main part is comprised by the exterior body 10 which has the exterior label 11 stuck on the outer periphery.

The exterior body 10 includes a pair of wide surfaces (indicated only on one wide surface 10a on the drawing) that face each other in the thickness direction (Z direction) and a side surface surrounding the wide surface (on the drawing, two of the four side surfaces). It has a flat rectangular shape with only the side surfaces 10b and 10c.
On the side surface 10c, five terminals 23a to 23e are exposed through the window portion. Of the five terminals 23a to 23e, the terminals 23a to 23c are external connection terminals, and the terminals 23d and 23e are test terminals. The terminals 23d and 23e are covered with a submergence determination seal 13 from above so as not to touch the user's eyes.
2. Configuration of Cell Phone Device When Battery Pack is Stored FIG. 2A is a front view showing an example of a cell phone device in which the battery pack is stored. As shown in the figure, the main part of the front surface 100 a of the mobile call device 100 is composed of a receiver unit 101, a display unit 102, and a button unit 103 provided on the front surface of the housing 110.

FIG. 2B is a rear perspective view showing the configuration of the mobile call device 100. As shown in the figure, the back surface 100b of the mobile phone 100 has a housing portion 104 for housing the battery pack 1 provided on the back surface portion of the housing 110 and a main body portion 106 for housing the device main body portion. Yes.
The battery pack 1 is accommodated with the other wide surface 10 a (see FIG. 1) facing the wide surface 10 d of the pair of wide surfaces in the exterior body 10 facing the bottom surface 104 a of the housing portion 104. Further, a terminal portion 105 is provided on the side surface of the accommodating portion 104, and the terminal portion 105 and the terminals 23a to 23c of the battery pack 1 are connected when the battery pack 1 is accommodated.

FIG. 2C is a cross-sectional view of the configuration of the mobile phone 100 as seen from the side. As shown in the figure, a reception unit 101 is located on the front surface 100 a of the mobile call device 100, and a storage unit 104 is located on the back side of the reception unit 101. The battery pack 1 is accommodated with the wide surface 10 a of the pair of wide surfaces 10 a and 10 d of the exterior body 10 facing the bottom surface 104 a of the accommodating portion 104, and the accommodating portion 104 is sealed by the outer lid 106. The Here, of the pair of opposed wide surfaces 10a and 10d, the wide surface 10a is located on the device side (the upper side in the drawing) of the accommodating portion 104, and the wide surface 10a corresponds to the above-described first exterior main surface. The wide surface 10d corresponds to the other wide surface (hereinafter also referred to as “exterior second main surface”).
3. As shown in FIG. 3, the core pack 20 provided in the battery pack 1 includes a unit cell 30, a circuit board 23 connected thereto, and a board holder 24 interposed therebetween. Composed.

  The unit cell 30 includes a pair of wide surfaces (in the drawing, only one wide surface 30a is indicated) opposed to each other in the thickness direction (Z direction) and a side surface surrounding the wide surface (on the drawing, one of the four side surfaces). It has a flat rectangular shape with only the side face 30c. Here, in the housing state shown in FIG. 2C, the wide surface 30a of the pair of wide surfaces of the unit cell 30 is located on the device side (upper side in the drawing) of the housing portion 104, and the exterior first main surface 10a. Are positioned on the wide surface 30a side. Therefore, the wide surface 30a corresponds to the battery first main surface described above. Hereinafter, the other wide surface is also referred to as “battery second main surface”.

A magnetic sheet 40 is provided on the battery first main surface 30 a of the unit cell 30. More specifically, the magnetic sheet 40 is provided on a central region that is a partial region of the battery first main surface 30a. Here, an adhesive layer (not shown) for holding the magnetic sheet 40 on the battery first main surface 30a is interposed between the magnetic sheet 40 and the battery first main surface 30a.
The battery first main surface 30a is rectangular, but the “central region” of the battery first main surface 30a is a rectangular shape projected when only the unit cell 30 is projected onto the XY plane. Each of the short side (side along the Y-axis direction) and the long side (side along the X-axis direction) is translated by an arbitrary distance inside the unit cell 30 and is surrounded by these translated sides. It shall mean an area. In the battery first main surface 30a, it is sufficient that at least the central region and the remaining peripheral region excluding the central region are formed. For example, in the present embodiment, only the unit cell 30 is projected onto the XY plane. The long side is about 60 mm, the short side is about 45 mm, and the central region has a rectangular shape with a long side of about 50 mm and a short side of about 20 mm.
4). Configuration of Core Pack As shown in FIG. 4, in the core pack 20, a negative electrode terminal 33 projects from the side surface 30 b of the unit cell 30 that forms the end surface of the sealing plate 32 that configures the unit cell 30. The negative electrode terminal 33 is insulated from the side surface 30b. Moreover, in the core pack 20, the side surface 30b which makes the end surface of the armored can 31 and the sealing board 32 which comprise the unit cell 30 plays the role of a positive electrode terminal.
A PTC (Positive Temperature Coefficient) element 26 is connected to the negative electrode terminal 33 via an insulating plate 25 provided with an opening through which the negative electrode terminal 33 passes. Further, a clad plate 27 is joined to a side surface 30b that forms an end face of the sealing plate 32, and the clad plate 27 is connected to a conductive land of the circuit board 23 via a connection lead 28 bent into a U-shape. (Not shown).
5. Configuration of Magnetic Sheet As shown in FIGS. 3 and 4, the magnetic sheet 40 is provided on the battery first main surface 30 a of the unit cell 30.

The magnetic sheet 40 is obtained by mixing a magnetic metal material and a polymer into a sheet shape. As the magnetic metal material, a material having a higher magnetic permeability and superior mechanical strength and workability is preferable. For example, an amorphous alloy is preferable, and a Co-based amorphous alloy is more preferable.
As for the thickness of the magnetic sheet 40, the effect of reducing the magnetic field strength increases as the thickness increases until the penetration depth of the magnetic field lines is reached. Therefore, the thickness of the magnetic sheet 40 is preferably at least 10 μm or more. On the other hand, the upper limit of the thickness of the magnetic sheet 40 is not particularly limited and may be, for example, 200 μm or less. However, since an increase in the thickness of the magnetic sheet leads to an increase in the thickness of the battery pack 1, the thickness of the battery pack 1 is reduced. Considering this, it is preferable that the thickness is 60 μm or less.
6). Configuration of Unit Cell As shown in FIG. 5A, the electrode body 34 is accommodated in a metal outer can 31 constituting the unit cell 30. The opening of the outer can 31 is sealed by the sealing plate 32 in a state where the resin spacer 35 and the insulating plate 36 are placed on the electrode body 34 (upper in the X-axis direction) in the outer can 31.

The sealing plate 32 is attached with a negative electrode terminal 33 projecting upward from the outer principal surface in the X-axis direction. The negative electrode terminal 33 has an electrode body within the outer can 31 sealed with the sealing plate 32. A negative electrode lead tab connected to the negative electrode plate (negative electrode element) 34 is connected.
On the other hand, the positive electrode lead tab connected to the positive electrode plate (positive electrode element) of the electrode body 34 is sandwiched between the inner surface of the outer can 31 and the outer edge of the sealing plate 32 at the opening edge of the outer can 31. In the state, it is joined to the outer can 31 and the sealing plate 32 by laser welding or the like. And the outer surface of the armored can 31 and the outer surface of the sealing board 32 become a positive electrode terminal.

  As shown in FIG. 5B, the electrode body 34 is formed by winding a strip-like positive electrode plate (positive electrode element) and a negative electrode plate (negative electrode element) with a separator interposed therebetween, It is configured to be flattened according to the shape. A non-aqueous electrolyte containing an organic polymer or an electrolyte salt is held between the positive electrode plate and the negative electrode plate. The positive electrode plate and the negative electrode plate are connected to a positive electrode lead tab 37 and a negative electrode lead tab 38, respectively.

The unit cell 30 having the above-described configuration is a thin nonaqueous electrolyte secondary battery such as a lithium ion secondary battery. The outer can 31 and the sealing plate 32 are made of an alloy of a metal material such as aluminum, for example.
7). Superiority (Overview)
4 and 5, in the core pack 20, when the unit cell 30 is discharged, from the positive electrode plate of the electrode body 34, the positive electrode lead tab 37, the outer can 31 that is a positive electrode terminal, the circuit board 23, the PTC element 26, A current path that returns to the negative electrode plate of the electrode body 34 via the negative electrode terminal 33 and the negative electrode lead tab 38 is formed. Therefore, an interlinkage magnetic flux is generated around the unit cell 30 with the electrode body 34 as a base point.

  Here, the exterior of the unit cell 30 is composed of a metal outer can 31 and a sealing plate 32. The metal material constituting these members must be selected not only from the viewpoint of increasing the magnetic permeability but also from the viewpoint of workability and weight reduction. Therefore, an aluminum alloy that is a material having a relatively low magnetic permeability is selected. Yes. Therefore, the electromagnetic field cannot be confined in the unit cell 30 and an electromagnetic field is induced around the unit cell 30. Further, if the thickness of the outer can 31 and the sealing plate 32 is increased, the shielding effect of the electromagnetic field can be enhanced, but it is contrary to weight reduction and is therefore difficult to select.

In the battery pack 1 according to the present embodiment, as shown in FIG. 3 and the like, the magnetic sheet 40 is provided on the battery first main surface 30 a of the unit cell 30. Therefore, the magnetic flux generated around the battery first main surface 30 a by the magnetic metal in the magnetic sheet 40 is bent toward the magnetic sheet 40. As a result, it is possible to reduce the magnetic field strength above the battery first main surface 30a, and as a result, the battery pack 1 is induced on the receiver 101 side of the mobile call device 100 in the state of being accommodated in the mobile call device 100. It is possible to reduce the magnitude of the electromagnetic field.
(About wound cell)
In the battery pack 1 according to the present embodiment, the electrode body 34 has a wound structure as shown in FIG. FIG. 6A shows a schematic cross-sectional view of the unit cell 30 of FIG. 5B viewed from the ZY plane. As shown in FIG. 6A, it can be said that the direction of the electric field E generated in the electrode body 34 when the unit cell 30 is discharged is along the strip-shaped electrode plate. The direction of the electric field is the same along the X-axis direction, and the electric field generated in the electrode body 34 can be said to be the same as when the coil is wound around the X-axis.
FIG. 6B shows a schematic cross-sectional view of the unit cell 30 shown in FIG. 5B when viewed from the XZ plane, with the magnetic sheet 40 removed, and FIG. 6C with the magnetic sheet 40 provided. ). Since the electric field in the electrode body 34 of the unit cell 30 is as shown in FIG. 6A, the magnetic field B generated in the unit cell 30 is generated from the sealing plate 32 in the X-axis direction as shown in FIG. Along the inside of the unit cell 30 and returns to the sealing plate 32. Here, the schematic shape of the magnetic field shown in FIG. 6B is consistent with the measurement result of the magnetic field strength (FIG. 10) described later.
Then, as shown in FIG. 6C, the magnetic field B generated in the unit cell 30 is bent toward the magnetic sheet 40 by providing the magnetic sheet 40 on the battery first main surface 30a. The magnetic field intensity above the main surface 30a is reduced.
(Summary)
As described above, by providing the magnetic sheet 40, the magnetic field strength on the upper side of the battery first main surface 30a can be reduced with respect to the electromagnetic field using the unit cell 30 as a generation source. Here, the shape of the magnetic field generated in the unit cell 30 is, for example, an arrangement of electrode plates such as whether the electrode body is a laminated structure in which a positive electrode plate and a negative electrode plate are laminated, or a wound structure as shown in FIG. Varies with structure. However, regardless of the structure of the electrode body, an electromagnetic field is generated on the device side of the unit cell (above the battery first main surface 30a), although the magnitude of the magnetic field strength is different. It can be said. Therefore, by providing the magnetic sheet according to the present invention, the magnetic field strength on the device side of the unit cell (above the battery first main surface 30a) can be reduced. Here, when the winding structure shown in FIG. 5B is adopted, it can be said that the magnetic field strength generated on the battery first main surface of the unit cell tends to be relatively large as shown in FIG. For this reason, when the electrode body has a wound structure, it is particularly useful to provide the magnetic sheet according to the present invention.
[Embodiment 2]
1. Configuration of Battery Pack 5 for Mobile Phone Device FIG. 7 is a perspective view showing the external appearance of the battery pack 5 and a cross-sectional view of a virtual plane S surrounded by a dot-and-dash point in the drawing showing an enlarged main part.

  As shown in FIG. 7, the battery pack 5 as a whole has a flat rectangular appearance having a pair of wide surfaces parallel to the XY plane and four side surfaces surrounding the pair of wide surfaces. As shown in the enlarged view of the main part, the exterior of the battery pack 5 is the same as the exterior body 10 of the battery pack 1 according to the first embodiment, and the exterior label 51 constituting the exterior body 50 is arranged on the outer periphery of the unit cell. It is the structure which stuck. However, the magnetic sheet 70 is provided on the central region of the exterior first main surface 50 a of the exterior body 50, which is the main surface of the exterior label 51, and a protective sheet 71 for protecting the magnetic sheet 70 is provided by the exterior label 51. The magnetic sheet 70 is different in that it is provided on the entire area of the outer surface of the exterior label 51 so as to sandwich the magnetic sheet 70 in the thickness direction (Z direction).

  In addition, the exterior label 51 and the protective sheet 71 can be comprised, for example from the same resin material, and can also be comprised as the same member. Here, the exterior label 51 has a function of protecting the unit cell from external impact and ensuring electrical insulation between the unit cell and the outside. On the other hand, the protective sheet 71 prevents corrosion of the magnetic sheet 70. Since it has the function which complements mechanical strength, paying attention to the difference of these functions, the exterior label 51 and the protection sheet 71 are made into another member.

The battery pack 5 has an outer package at the left end in the Y-axis direction, and an external lead 68 connected to the external connection terminal 69 extends from a portion in front of the X-axis direction.
In the present embodiment, unlike the first embodiment, the magnetic sheet 70 is provided on a central region that is a partial region of the exterior first main surface 50 a of the exterior body 50. Here, the “central region” refers to that given by the same definition as the “central region” of the battery first main surface 30a when the exterior body 50 is projected onto the XY plane. Therefore, the exterior first main surface 50a only needs to be formed with at least the central region and the remaining peripheral region excluding the central region. For example, in the present embodiment, only the exterior body 50 is projected onto the XY plane. In this case, the long side is about 60 mm and the short side is about 45 mm, and the central region has a rectangular shape having a long side of about 50 mm and a short side of about 20 mm.
2. Configuration of Core Pack As shown in FIG. 8, in the battery pack 5 according to the present embodiment, unlike the unit cell 30 of the battery pack 1 according to the first embodiment, the unit cell 60 having a flat rectangular external shape is a metal. A secondary battery including a laminate exterior 61 is configured. In the unit cell 30 according to the first embodiment, the magnetic sheet 40 is provided on the battery first main surface 30a. However, in the unit cell 60 according to the present embodiment, the battery first main surface 61a includes A magnetic sheet is not provided.
In the unit cell 60 according to the present embodiment, positive and negative electrode tabs 62 and 63 are extended from a sealing portion 61 b on the left side in the X-axis direction of the metal laminate exterior 61.

The negative electrode tab 62 of the unit cell 60 is bent upward in the Z-axis direction of the sealing portion 61b, and the connection lead portion of the PTC element 64 is joined to the tip portion. Here, an insulating sheet (not shown) is interposed between the metal laminate exterior 61 constituting the exterior of the unit cell 60 and the bent negative electrode tab 62 and the connection lead portion of the PTC element 64.
On the other hand, the positive electrode tab 63 of the unit cell 60 is bent to the lower side (back side) in the Z-axis direction of the sealing portion 61b, and the connection lead 65 is joined to the tip portion. Here, similarly to the above, an insulating sheet (not shown) is interposed between the metal laminate exterior 61 and the bent positive electrode tab 63 and connection lead 65.

The PTC element 64 is connected to a conductive land (not shown) of the circuit board 66 on which the control IC 67 is mounted with a U-shaped tip portion extending from the outer surface to the upper side in the Z-axis direction. The connection lead 65 has an L shape, and is connected to a conductive land (not shown) of the circuit board 66 at the U-shaped tip portion on the right side in the Y-axis direction.
3. Other Configurations Except for the elements described above, including the configuration of the magnetic sheet 70 and the unit cell 60, the same configuration as that of the first embodiment can be adopted, and thus the description thereof is omitted. Here, the protection sheet 71 will be described for the magnetic sheet 70.

  The protective sheet 71 is provided for the purpose of preventing corrosion of the magnetic sheet 70 and complementing mechanical strength. If the object can be achieved, the constituent material of the protective sheet 71 is not limited. For example, the protective sheet 71 can be substituted for the function of the external label 51 by forming the protective sheet 71 from the same resin material as the constituent material of the external label 51. it can. Further, if the exterior label 51 and the protective sheet 71 are formed using the same constituent material, the magnetic sheet and the protective sheet can be easily formed on the exterior label by a known printing method. In addition, the protective sheet can be easily and integrally formed.

The thickness of the protective sheet 71 is not particularly limited, but excessively thickening may hinder the thinning of the battery pack 5 and the effect of the magnetic sheet 70. Is preferably 10 μm or more and 50 μm or less.
The protective sheet 71 only needs to be able to cover the magnetic sheet 70, and may be provided only on a partial region of the exterior first main surface 50a. Further, the magnetic sheet 70 has good corrosion resistance and mechanical strength. If it exists, it is not necessary to provide, and the structure which provides a protection sheet in this invention is not essential.
4). Superiority In the battery pack 5 according to the present embodiment, the magnetic sheet 70 is provided on the exterior first main surface 50 a of the exterior body 50. The exterior first main surface 50a is located on the battery first main surface 61a side of the unit cell 60. When the battery pack 5 is housed in a mobile phone, the exterior first main surface 10a shown in FIG. It is assumed that it is in the same position.

Therefore, by providing the magnetic sheet 70, it is possible to reduce the magnitude of the electromagnetic field induced on the receiver side of the portable telephone device that uses the unit cell 60 as a source during charging and discharging.
[Verification experiment]
Hereinafter, various experiments verifying the effects of the present invention produced by providing a magnetic sheet will be described.

<About the effect of magnetic sheet>
(Measurement condition)
A unit cell 30 according to the first embodiment is prepared, and a magnetic sheet 40 is provided on the entire area of the outer surface of the unit cell 30 as shown in FIGS. 9A, 9B, and 9C. 9 (a), a magnetic sheet 40 provided on the peripheral region of the battery first main surface 30a of the unit cell 30, on the side surface 30b forming the end surface of the sealing plate, and on the other side surface facing the side surface 30b ( FIG. 9 (b)) and the one provided with the magnetic sheet 40 on the four side surfaces of the unit cell 30 (FIG. 9 (c)) were used as verification samples. In addition, a sample in which the magnetic sheet 40 was not provided for the unit cell 30 was used as a comparative sample. Here, the unit cell 30 was a lithium ion secondary battery, the magnetic metal material constituting the magnetic sheet 40 was a Co-based amorphous alloy having a magnetic permeability of 75000, and the thickness of the magnetic sheet 40 was 18 μm.
Then, a battery tester is connected to the positive electrode terminal and the negative electrode terminal of the unit cell 30, and under the load of the GSM (Global System for Mobile communications) standard as a load under the same condition as the use condition in the portable telephone device, The unit cell 30 was discharged with a GSM standard pulse current (frequency: 217 Hz). In the discharge state, as shown in FIG. 9 (d), the height h of the unit cell 30 from the battery first main surface 30a is 1 cm, and on the measurement surface S of 13 cm × 18 cm, The magnetic field strength was measured by scanning the measurement probe (the coil winding axis is the Z-axis direction). Here, the measurement position was set for each 1 cm in the X-axis direction and the Y-axis direction, and the holding time at each measurement position was set to 1 second. Moreover, in order to prevent electromagnetic wave noise from the outside, it measured in the dark room where the magnetic shield was made. Of the obtained measurement results, a measurement result on a chain line corresponding to the center of the battery first main surface 30a shown in FIG. 9D is shown as a representative in FIG.
(Measurement results and discussion)
The measurement results shown in FIGS. 10 (a), 10 (b), and 10 (c) show the measured values of the magnetic field strength B obtained with respect to changes in the magnetic field strength in the X-axis direction. Respectively. Note that, in the vicinity of the end of the unit cell (cell), the magnetic field strength in each axial direction (particularly in the Z-axis direction) is judged to be better as the magnetic field strength is further reduced toward the reference value of −20 dBA / m. did.
As shown in FIG. 10, it can be seen that the magnetic field strength B is smaller in the case where the magnetic sheet is provided than in the case where the magnetic sheet is not provided. That is, it is shown that the magnetic field strength above the battery first main surface is reduced by providing the magnetic sheet.
Here, in the measurement results for the magnetic sheet not provided, the magnetic field strength Bx tends to increase from both ends of the unit cell (cell) toward the central region in the X-axis direction (FIG. 10A). The magnetic field strength Bz shows a tendency to decrease in the X-axis direction after increasing in a convex quadratic curve shape from both ends of the unit cell (cell) toward the central region (FIG. 10C). This indicates that the magnetic field generated around the unit cell is consistent with the schematic magnetic field shown in FIG.
In addition, as shown in FIG. 10, a magnetic sheet is provided only on the entire side surface of the unit cell (FIG. 9C), and a magnetic sheet is provided on the peripheral region of the battery first main surface of the unit cell. It can be seen that the effect of reducing the magnetic field strength increases in the order of (FIG. 9B), in which the magnetic sheet is provided over the entire outer surface of the unit cell (FIG. 9A). This result shows that the effect of reducing the magnetic field strength is more manifested when the magnetic sheet is provided on the first main surface of the battery than when the magnetic sheet is provided on the side surface of the unit cell.
<Arrangement position of magnetic sheet and constituent material of magnetic sheet>
(Measurement condition)
In order to examine a favorable arrangement position and constituent materials related to the magnetic sheet, as shown in FIG. 11, a magnetic sheet 40 is provided on the central region of the battery first main surface 30a of the unit cell 30 (FIG. 11). (A)), what provided the magnetic sheet 40 on the peripheral area | region of the battery 1st main surface 30a of the unit cell 30 (FIG.11 (b)), and the thing which does not provide the magnetic sheet 40 in the unit cell 30 were prepared. . Here, the magnetic sheet 40 shown in FIG. 11A has a rectangular shape with a long side in the X-axis direction of 45 mm and a short side in the Y-axis direction of 20 mm, and the X-axis of the rectangular battery first main surface 30a. 7 mm from the long side in the direction toward the Y-axis direction, and 3 mm from the short side in the Y-axis direction toward the X-axis direction. Further, each of the magnetic sheets 40 shown in FIG. 11B has a rectangular shape having a long side in the X-axis direction of 45 mm and a short side in the Y-axis direction of 5 mm so as to overlap the long side of the battery first main surface 30a. Are arranged along the long side.
Furthermore, with respect to the one shown in FIG. 11A, the magnetic metal material constituting the magnetic sheet 40 is a Co-based amorphous alloy having a magnetic permeability of 75000 and the thickness of the magnetic sheet 40 is 22 μm, A verification sample 2 in which the magnetic metal material constituting the magnetic sheet 40 is an Fe-based nanocrystalline alloy having a magnetic permeability of 50000 and the thickness of the magnetic sheet 40 is 18 μm is prepared. Further, with respect to the one shown in FIG. 11B, a verification sample 3 in which the magnetic metal material constituting the magnetic sheet 40 is a Co-based amorphous alloy having a magnetic permeability of 75000 and the thickness of the magnetic sheet 40 is 18 μm; The verification sample 3 is the same as the verification sample 4 except that the thickness of the magnetic sheet 40 is set to 36 μm. The magnetic metal material constituting the magnetic sheet 40 is an Fe-based amorphous alloy having a magnetic permeability of 10,000 and the magnetic sheet. A verification sample 5 having a thickness of 40 having a thickness of 25 μm was prepared.
Then, the magnetic field strength was measured under the same conditions as the above-described measurement conditions related to the experimental results shown in FIG. Of the obtained measurement results, the measurement results on the alternate long and short dash point shown in FIG. 9 (d) are represented, the measurement results on FIG. 11 (a) are shown in FIG. 12, and the measurement results on FIG. The results are shown in FIG.
(Measurement results and discussion)
The measurement results shown in FIGS. 12 (a), 12 (b), and 12 (c) show the measured values of the magnetic field strength B obtained with respect to changes in the magnetic field strength in the X-axis direction. Respectively.
As shown in FIG. 12, in the samples 1 and 2 in which the magnetic sheet is provided on the central region of the first main surface of the battery, the magnetic field strength is dramatically reduced as compared with the sample without the magnetic sheet. I understand that. Further, in contrast to the measurement results shown in FIG. 10, it is possible to reduce the magnetic field strength to the same extent even when the magnetic sheet is provided over the entire region of the outer surface of the unit cell. I understand. This result shows that even in a partial region of the battery first main surface of the unit cell, it is preferable to provide the magnetic sheet particularly in the central region from the viewpoint of further reducing the magnetic field strength.
It can also be seen that Sample 1 and Sample 2 have the same effect of reducing the magnetic field strength. As a result, the magnetic metal material constituting the magnetic sheet is made of a material having a relatively high magnetic permeability, such as a Co-based amorphous alloy (Sample 1) or an Fe-based nanocrystalline alloy (Sample 2). It shows that it can be reduced. However, when an Fe-based nanocrystalline alloy is used as a magnetic metal material, it is not excellent in mechanical strength, so that it may be necessary to further provide a reinforcing layer on the magnetic sheet. Considering the mechanical strength of the magnetic sheet, it is preferable to use a Co-based amorphous alloy as the magnetic metal material.
The measurement results shown in FIGS. 13 (a), 13 (b), and 13 (c) show the measured values of the magnetic field strength B obtained with respect to changes in the magnetic field strength in the X-axis direction, in the X-axis direction, Y-axis direction, and Z-axis direction. Respectively.
As shown in FIG. 13, in the samples 3, 4 and 5 in which the magnetic sheet is provided on the peripheral region of the battery first main surface, the magnetic field strength is dramatically reduced as compared with the sample without the magnetic sheet. I understand that Compared with the results shown in FIG. 12, the magnetic sheet is inferior to that provided on the central region of the battery first main surface, but the magnetic sheet is provided on a partial region of the battery first main surface. Thus, it can be seen that the effect of reducing the magnetic field strength appears more favorably.
Sample 3 and sample 4 differ only in the thickness of the magnetic sheet, but it can be seen that the effect of reducing the magnetic field strength is comparable. This result shows that the effect of reducing the magnetic field strength is satisfactorily exhibited when the thickness of the magnetic sheet is at least 18 μm or more. However, from the viewpoint of thinning the battery pack, the upper limit of the thickness of the magnetic sheet is preferably 60 μm.
Further, in Sample 5, the magnetic sheet is made of a magnetic metal material having a lower magnetic permeability than Samples 3 and 4, but the effect of reducing the magnetic field strength is almost the same as Samples 3 and 4. I understand that This result shows that the effect of reducing the magnetic field strength is satisfactorily exhibited when the magnetic permeability is at least 10,000 or more. Further, in contrast to the results of Samples 1 and 2 above, by using an amorphous alloy such as an Fe-based amorphous alloy or a Co-based amorphous alloy as a magnetic metal material, the mechanical strength of the magnetic sheet can be secured and the magnetic field strength can be reduced. Can be expressed well.

[Other matters]
(Electrode structure)
In the first and second embodiments, the electrode structure of the electrode body 34 constituting the unit cells 30 and 60 is taken as an example of a wound type, but a stacked structure in which a positive electrode plate and a negative electrode plate are stacked. Can also be adopted.

In the first and second embodiments, the electrode body 34 constituting the unit cells 30 and 60 is wound counterclockwise around the X-axis direction with respect to the bipolar plates (see FIG. 6A). As an example, it is possible to adopt various configurations that are wound clockwise or counterclockwise around an arbitrary axial direction.
(Appearance of unit cell)
In the first and second embodiments, the unit cell 30 or 60 has a flat rectangular external shape as an example, but it is possible to adopt a known external shape such as a cylindrical shape or a rectangular shape.

(Battery pack components)
In the said Embodiment 1, 2, while providing the exterior bodies 10 and 50 which exteriorize the unit cells 30 and 60, the exterior labels 11 and 51 which comprise the exterior bodies 10 and 50 with respect to the outer surface of the unit cells 30 and 60 are provided. As an example, a structure for sticking is used. However, the configuration of the exterior body is not limited to this. An example of another configuration will be described with reference to FIG.

  FIG. 14 is an exploded perspective view of the battery pack 90. As shown in the figure, the battery pack 90 includes an outer case having an upper case 80 and a lower case 81. The upper case 80 and the lower case 81 are joined by engaging the convex portion 82 with the concave portion 83 and performing ultrasonic welding in a state where the core pack 20 is stored. In this manner, the core pack 20 is housed in the bottomed cylindrical outer case having an opening on the circuit board 23 side constituting the core pack 20. And the bottom case 12 is arrange | positioned on the circuit board 23, and the exterior label 11 is affixed on the outer periphery.

As described above, in the battery pack 90 shown in FIG. 14, the configuration of the exterior body that covers the unit cell 30 includes the exterior case that houses the unit cell 30, and the exterior label 11 that is attached to the outer surface of the exterior case. It is supposed to have. As described above, various configurations of the exterior body that covers the unit cells can be employed.
Here, when the configuration including the exterior case is adopted, as shown in FIG. 14, the battery first of the pair of wide surfaces in the exterior case exhibiting a flat rectangular shape according to the exterior shape of the unit cell 30. It is possible to employ a configuration in which the magnetic sheet 40 is disposed on the wide surface 80a located on the side of the first main surface 30a.
Hereinafter, of the pair of wide surfaces in the exterior case, the wide surface located on the battery first main surface side is also referred to as “case first main surface”, and the other wide surface is also referred to as “case second main surface”. .

(Arrangement position of magnetic sheet)
In the first and second embodiments, the configuration in which the magnetic sheets 40 and 70 are provided on the battery first main surface 31a of the unit cell 30 or the exterior first main surface 51a of the exterior body 50 is employed as an example. In this case, the magnetic sheet only needs to be at least on the device side of the unit cell, and when the unit cell has a flat rectangular external shape, it may be any one that covers at least a part of the battery first main surface. Therefore, it is possible to adopt a configuration in which a magnetic sheet is also provided on or above the battery second main surface, which is the other main surface facing the battery first main surface of the unit cell, or the side surface surrounding the main surface. Is possible.

Specifically, the following variations can be employed.
The magnetic sheet may be configured to be provided on at least one of the battery first main surface, the case first main surface, or the exterior first main surface. The first main surface of the battery, the first main surface of the case, or the first main surface of the exterior has relatively flatness, and the area thereof is also ensured to be larger than the surfaces of the other components. Therefore, from the viewpoint of preventing the magnetic sheet from being bent on the arrangement surface and further expressing the effect of reducing the magnetic field strength, and from the viewpoint of ensuring the degree of freedom related to the arrangement position of the magnetic sheet, the magnetic sheet is used. It is desirable to provide it on at least one of the first main surface of the battery, the first main surface of the case, or the first main surface of the exterior.

  Here, if the magnetic sheet is disposed on at least one of the first main surface of the battery, the first main surface of the case, or the first main surface of the exterior, the effect of reducing the magnetic field strength is excellent. To express. However, since the magnetic flux density related to the magnetic field induced by the unit cell increases as the distance from the unit cell becomes shorter, the magnetic sheet is the first main battery from the viewpoint of expressing the effect of reducing the magnetic field strength by the magnetic sheet. It is desirable to provide it on the surface.

  On the other hand, the distance between the battery first main surface and the exterior first main surface in the thickness direction is usually about 0.4 mm. Therefore, for example, even if the magnetic sheet is provided on the exterior first main surface or the case first main surface, the effect of reducing the magnetic field strength by the magnetic sheet is remarkably higher than that provided on the battery first main surface. It does not decrease. Therefore, for example, when the magnetic sheet is disposed on either the battery first main surface or the exterior first main surface, the magnetic field intensity above the battery first main surface related to the electromagnetic field using the unit cell as a source. It is also possible to adopt a configuration in which the magnetic sheet is provided on the exterior first main surface in consideration of the simplicity of the operation for arranging the magnetic sheet without bending, and the like.

  In addition, a magnetic sheet may be provided on the battery second main surface, side surface or above them in the unit cell, but as shown in the verification experiment, if the magnetic sheet covers the battery first main surface, A significant shielding effect is observed. Therefore, it is desirable to provide the magnetic sheet only on the battery first main surface, the case first main surface, or the exterior first main surface from the viewpoint of reducing the thickness of the battery pack and reducing the cost.

Further, the magnetic sheet is provided on a partial region of the battery first main surface, the case first main surface or the exterior first main surface without covering the entire region of the first main surface of the unit cell with the magnetic sheet. By adopting it, it is possible to further reduce the cost.
In addition to the above configuration, a configuration in which a magnetic sheet is provided on the wiring substrate via an insulating sheet may be employed as long as the wiring substrate is provided on the first battery main surface of the unit cell. Furthermore, various configurations such as a configuration in which a magnetic sheet is provided in a region facing the battery first main surface on the inner peripheral surface of the exterior case can be employed.

(About verification experiment)
In the verification experiment, the unit cell according to the first embodiment is targeted. However, as is clear from the experiment result, the unit cell 60 according to the second embodiment is also provided as a target by providing the magnetic sheet 70. It can be said that the result which shows the effect which reduces the magnetic field intensity above the battery 1st main surface is obtained.

  INDUSTRIAL APPLICABILITY The present invention is useful for realizing a battery pack capable of reducing the magnitude of an electromagnetic field induced to the outside as an operation power source for a portable telephone device or the like.

1,5,90 Battery pack for mobile phone 10, 50 Exterior body 11, 51 Exterior labels 10a, 10d, 50a Wide surface 10b, 10c, 50b of exterior body 12 Side surface of bottom body 20 Core pack 30, 60 Element Battery 30a, 61a Wide surface 30b, 30c of unit cell Side surface 34 of unit cell Electrode body 40, 70 Magnetic sheet 100 Mobile phone 101 Reception unit 104 Storage unit

Claims (8)

A battery pack for a mobile phone device accommodated in a housing part provided on the back surface of the mobile phone device case,
Comprising a unit cell and a magnetic sheet;
In the storage state in the storage unit, the magnetic sheet is disposed on the device side of the unit cell as a member that shields an electromagnetic field generated on the device side of the unit cell using the unit cell as a generation source.
A battery pack for mobile phone devices. The unit cell includes an electrode body wound in a state in which a positive electrode element and a negative electrode element are arranged to face each other with a separator interposed therebetween.
The battery pack for portable telephone devices according to claim 1. The unit cell has a flat rectangular appearance.
In the storage state in the storage portion, the magnetic sheet is either on the first battery main surface located on the device side or above the first battery main surface, of the pair of wide surfaces of the unit cell. Arranged in the
The battery pack for a portable telephone device according to claim 1 or 2, characterized in that The exterior of the unit cell is further provided with an exterior body having a flat rectangular appearance,
The magnetic sheet includes at least one main surface of the battery first main surface of the unit cell, or the exterior first main surface positioned on the battery first main surface side of the pair of wide surfaces of the exterior body. Arranged above,
The battery pack for portable telephone equipment according to claim 3. The magnetic sheet is disposed on a central region of the battery first main surface or the exterior first main surface,
The battery pack for a portable telephone device according to claim 4. The magnetic sheet is made of a magnetic metal material made of a Co-based amorphous alloy.
The battery pack for portable telephone devices according to any one of claims 1 to 5, characterized in that The thickness of the magnetic sheet is 10 μm or more and 200 μm or less.
The battery pack for a mobile telephone device according to any one of claims 1 to 6, The unit cell is a lithium ion secondary battery.
The battery pack for portable telephone devices according to any one of claims 1 to 7, wherein the battery pack is a mobile phone.

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