JP6351393B2 - Battery module manufacturing method and portable electronic device manufacturing method - Google Patents

Description

  The present invention relates to a battery module for wireless power feeding using a planar coil, a portable electronic device equipped with the battery module, and a method for manufacturing the battery module.

  Conventionally, portable electronic devices may be required to have a waterproof function. Since it is desirable that the portable electronic device having such a waterproof function avoids exposure of the charging terminal, it is preferable to adopt a wireless power feeding method. Therefore, in recent years, a battery pack with a charging function by a wireless power feeding method provided with a coil has been developed.

  As an example of the battery pack with a charging function, Patent Document 1 discloses that a flat coil is disposed on a flat surface of a thin battery having a width wider than the thickness, and a planar coil is disposed through a sheet-like electromagnetic shield film, and charged by magnetic induction. A battery pack technology is disclosed.

  Here, when the battery pack disclosed in Patent Document 1 is wirelessly charged in a state where it is incorporated into a portable electronic device, or when it is incorporated into a portable electronic device after being wirelessly charged with a single battery pack. The following two usage situations are assumed. Therefore, the battery pack has a structure in which a battery and a coil are protected by assembling a number of components such as a substrate holder, a resin battery case covering the power receiving coil, and a coil protection rib. Moreover, the battery used with the said battery pack can form the exterior can which integrally molded each surface, and can be used as a metal case. That is, the battery has a robust structure using a metal case.

  On the other hand, the user of the portable electronic device may not handle the battery outside the portable electronic device case. For example, the battery is shipped in a state in which a battery is incorporated in advance in the portable electronic device case so that it cannot be easily opened and closed by the user, and the battery replacement operation is also performed at the manufacturing factory. As such a battery for portable electronic devices, for example, a battery technology disclosed in Patent Document 2 is known. Patent Document 2 discloses a laminated battery as a very thin secondary battery. The laminate battery is manufactured by laminating an exterior film on both surfaces of a battery element, and tightly adhering the exterior films on both sides at the periphery of the battery element. A laminated battery having such a structure is characterized by being thin and capable of increasing capacity as compared with a battery in which a battery element is inserted into a metal outer can.

JP 2013-2605 A JP 2005-183242 A

  However, when assembling a battery module to be charged by magnetic induction by arranging a planar coil on a flat surface of a laminated battery via a sheet-like electromagnetic shield film, the above-mentioned conventional technique solders the planar coil to a circuit board. It is necessary to perform a number of assembly operations such as bonding to the laminated battery together with the laminated battery. These assembly operations may cause various damages such as heat, scratches, pin poles, and dents on the surface of the laminated battery. In particular, soldering may cause thermal damage to the laminated battery surface. And the said damage becomes a cause which reduces the long-term reliability of a laminated battery. Therefore, there is a need for a highly reliable battery module configuration that does not cause thermal damage to the laminated battery.

  The present invention has been made in view of the above problems, and a main object of the present invention is to provide a battery module, a portable electronic device, and a battery module manufacturing method with high long-term reliability by preventing damage during assembly. That is.

In order to solve the above problems, the present invention has the following configuration.
A first invention includes a circuit unit comprising a planar coil, a circuit board, a coil lead member that electrically connects the planar coil and the circuit board, and a terminal lead member that is connected to the circuit board. And a step of welding and joining the circuit board of the circuit unit to the negative electrode terminal and the positive electrode terminal of the laminate battery.

According to the first aspect of the present invention, a planar coil, a circuit board, or the like related to the function of charging the laminated battery by electromagnetic induction to the battery module is integrated as a circuit unit in advance and connected to the circuit board in the circuit unit. And a laminated battery. In other words, since the laminated battery is connected to the integrated circuit unit, the surface of the laminated battery is subject to thermal damage, scratches, pin poles, assembling by incorporating individual components in the circuit unit into the battery module as in the prior art. There is no risk of damaging damage. Furthermore, in the battery module of the present invention, since the coil lead member connected to the planar coil in the circuit unit has flexibility, the planar coil can be arranged freely. For example, the planar coil can be arranged in a state separated from the laminate film by a predetermined distance. Therefore, it is possible to suitably prevent the eddy current from flowing through the laminated battery, in particular, the metal layer of the laminated film, due to the current generated in the planar coil, so that the reliability of the laminated battery can be improved.
Further, since the circuit unit, the negative electrode terminal, and the positive electrode terminal are connected by welding, it is possible to avoid the scattering of solder balls and the like as compared with the case of using solder.

According to a second invention, in the first invention, the planar coil is provided with a magnetic sheet on one surface.
According to a third invention, in any one of the first and second inventions, the planar coil includes an air core portion penetrating in a thickness direction, and a magnetic sheet embedded in the air core portion. Features.
According to the second and third inventions, since the magnetic sheet is provided on one surface of the planar coil and the air core portion of the planar coil, the transmitter is provided when the battery module is fed with the wireless power feeding transmitter. Improvement in coupling efficiency with the transmission coil can be expected.

In a fourth aspect based on the second aspect , a part of the coil lead member is connected to the magnetic sheet of the planar coil, and a connection portion between the coil lead member and the magnetic sheet is insulative. It has the sheet | seat reinforcement resin part covered with the reinforcement resin which consists of resin, It is characterized by the above-mentioned.
According to the fourth invention, since the insulating resin is provided at the connection portion between the coil lead member and the magnetic sheet, the tensile strength of the coil lead member can be improved.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the connecting portion between the coil lead member and the circuit board is a substrate reinforcing resin portion covered with a reinforcing resin made of an insulating resin. It is characterized by having.
According to the fifth invention, since the insulating resin is provided at the connection portion between the coil lead member and the circuit board, the tensile strength of the coil lead member can be improved.

A sixth invention is characterized in that, in the second or fourth invention, a surface of the magnetic material sheet on which the planar coil is not disposed is adhered to the laminated battery.
According to the sixth invention, since the planar coil is disposed at the fixed position, the coil lead member connected to the planar coil is less likely to jump out and is easy to handle. Further, in the battery module battery according to the present invention, since the planar coil and the laminated battery can be handled integrally, replacement maintenance is facilitated even when the battery module battery is incorporated in a portable electronic device.

A seventh invention is characterized in that, in the sixth invention, the outer shape of the magnetic sheet is the same as the outer shape of the laminated battery.
According to the seventh aspect, by forming the same outer shape as the attachment surface of the laminated battery 1, the reference position when attaching the planar coil to the magnetic sheet can be easily matched with the outer shape of the laminated battery.

An eighth invention is characterized in that, in the sixth or seventh invention, the magnetic sheet is laminated with a spacer sheet having a through hole, and the planar coil is disposed in the through hole. To do.
According to the eighth invention, since the planar coil is passed through the through hole of the spacer sheet, the planar coil can be fixed to the portable electronic device via the spacer sheet. In addition, since the spacer sheet and the planar coil have the same thickness, it is possible to flatten the fixing surface to the portable electronic device, and the area of the fixing surface is increased, so that the adhesive force when pasting to the portable electronic device is not impaired. .

A ninth invention is characterized in that, in the sixth invention, the magnetic sheet covers up to the side surface of the laminated battery to which the magnetic sheet is bonded.
According to the ninth aspect of the invention, since the magnetic sheet is covered up to the side surface to which the magnetic sheet is bonded, the swelling generated on the outer peripheral portion of the laminated film is prevented when the magnetic sheet covered with the planar coil is bonded to the laminated battery. As a result, strong adhesion is possible.

According to a tenth aspect of the invention, in any one of the seventh to ninth aspects of the invention, the magnetic sheet covered with the planar coil is formed of an adhesive seal portion of the laminated battery on the outer peripheral surface of the laminated battery. It is affixed to the surface which becomes a return | turnback base point.
According to the tenth invention, reliable and strong adhesion can be realized by sticking the magnetic sheet coated with the planar coil to the flat surface that is the folding base point of the adhesive seal portion of the laminate film.

An eleventh invention is characterized in that, in the eighth invention, the spacer sheet is fixed to a portable electronic device case via a heat conductive double-sided adhesive tape.
According to the eleventh aspect , since the thermally conductive double-sided adhesive tape is bonded to the upper layer of the spacer sheet, the planar coil can be more easily fixed to the portable electronic device.

A twelfth aspect of the present invention is a battery module manufactured by the method according to any one invention of the first to fifth invention is a manufacturing method of a portable electronic device which is fixed to the inner wall surface of the casing, the plane The coil is fixed to another inner wall surface different from the inner wall surface to which the laminate battery is fixed via a heat conductive double-sided adhesive tape.
According to the twelfth invention, the planar coil is fixed to the inner wall surface different from the fixed surface of the battery module in the inner wall surface of the casing of the portable electronic device, so that it is separated from the laminate film (metal film) constituting the laminate battery. A planar coil can be arranged, and the influence of heat generated by the planar coil can be mitigated.

  Therefore, the present invention can provide a highly reliable battery module, portable electronic device, and battery module manufacturing method by taking advantage of the advantages of lightweight, thin, and low cost, which are the characteristics of a laminated battery.

1 is a perspective view schematically showing a basic configuration of a battery module according to Example 1. FIG. It is a longitudinal cross-sectional view which shows the typical structure of the portable electronic device incorporating the battery module which concerns on Example 1. FIG. 3 is a schematic diagram for explaining an assembly method of the circuit unit and the laminated battery according to Example 1. FIG. 1 is a circuit diagram of a battery module according to Example 1. FIG. 6 is a schematic diagram for explaining a method of assembling a circuit unit and a laminated battery according to Example 2. FIG. 6 is a longitudinal sectional view schematically showing a configuration of a battery module according to Example 3. FIG. It is a longitudinal cross-sectional view along the AA cross section line of FIG. 6, Comprising: The battery module shown in FIG. 6 is typically shown in the state mounted in the portable electronic device. 10 is a longitudinal sectional view schematically showing a configuration of a battery module according to Modification 1. FIG. 10 is a longitudinal sectional view schematically showing a configuration of a battery module according to Modification 2. FIG. It is a longitudinal cross-sectional view which shows typically the structure of the portable electronic device incorporating the battery module shown in FIG.

Example 1
Hereinafter, the battery module, the portable electronic device, and the method for manufacturing the battery module according to the first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a schematic diagram illustrating a basic configuration of the battery module according to the first embodiment. FIG. 2 is a longitudinal sectional view schematically showing a state in which the battery module shown in FIG. 1 is incorporated in a portable electronic device. FIG. 3 is a schematic diagram showing a state before a circuit unit and a laminate battery constituting a battery module described later are connected. FIG. 4 is a circuit diagram according to the battery module shown in FIG.

“Battery module configuration”
First, the configuration of each part of the battery module 12 will be described.
The battery module 12 according to the first embodiment is configured to be incorporated into various portable electronic devices such as a smartphone and supply power to each unit, and can be charged via a transmitter (not shown) for wireless power feeding. The The battery module 12, at least a laminated battery 1 that supplies power to a portable electronic device, a planar coil 3 that is not attached to the laminated battery 1, a circuit board 5 that is placed on the laminated battery 1, and a planar coil 3 and a coil lead wire 4 that connects the circuit board 5 and a connector 10 that is connected to the circuit board 5 via the terminal lead wire 11 and serves as a power supply port to the portable electronic device. In the following description, the planar coil 3, the coil lead wire 4 (coil lead member), the circuit board 5, the connector 10, and the terminal lead wire 11 (terminal lead member) are collectively referred to as a battery. A configuration excluding the laminated battery 1 in the module 12 is a circuit unit 13.

  The laminated battery 1 is, for example, a chargeable / dischargeable secondary battery using Li having a high voltage of 3 to 3.7 V and a high energy capacity density. As shown in FIG. 2, the laminate battery 1 is formed by covering the peripheral surface of the electrode body 1a with a laminate film 1b and closely adhering the periphery of the electrode body 1a to each other in an airtight state.

  The electrode body 1a is obtained by laminating electrodes including a positive electrode material, a separator, and a negative electrode material in multiple layers. The laminate film 1b is configured to include a resin layer or metal layer film. As shown in FIG. 1, the laminate film 1b is formed to be longer than the electrode body 1a with respect to the longitudinal direction of the laminate battery 1. It has a shape that can be placed. The laminate battery 1 has a positive electrode terminal 15 and a negative electrode terminal 14 at a place (component mounting surface, terrace) of the circuit board 5 of the laminate film 1b, and can be electrically connected to the circuit board 5. Configured.

  The positive electrode terminal 15 is made of, for example, an Al material, and the negative electrode terminal 14 is made of, for example, an Ni material. The positive electrode terminal 15 and the negative electrode terminal 14 are welded to, for example, a pattern land portion covered with a Ni material on the back side of the component mounting surface of the circuit board 5. Since they are connected by welding, it is possible to avoid scattering of solder balls and the like as compared with the case of joining using solder. In addition, when the Al material of the positive electrode terminal 15 is difficult to weld, a Ni material thin plate may be relayed and welded to the Al material. Thereby, there is no spark and scattering at the time of welding, and the laminate film 1b can be welded without damage. As a connection method between the positive electrode terminal 15 and the pattern land portion of the negative electrode terminal 14 other than welding, a connection method that does not involve heat generation and scattering such as ultrasonic bonding, a connector, and crimping may be used.

  The planar coil 3 is, for example, an air core coil having a circular shape in plan view and having an air core portion penetrating in the thickness direction, and a single wire or a stranded wire having an insulating layer provided on the surface is spirally wound in substantially the same plane. It is a coil wound in a shape. The planar coil 3 is connected to the circuit board 5 via a coil lead wire 4 and is supplied with an alternating magnetic field transmitted at a resonance frequency or a frequency close to the resonance frequency from a transmission coil provided in a transmitter (not shown) for wireless power feeding. Electromagnetically coupled to generate an alternating current. Here, as shown in FIG. 1, the planar coil 3 is arranged in a state physically separated from the laminated battery 1, that is, in a state where it is not attached to the laminated battery 1. Specifically, as shown in FIG. 2, the planar coil 3 has a heat conductive double-sided adhesive silicone tape 19 (heat conductive double-sided adhesive tape) on the inner surface of a portable electronic device case 20 (casing of the portable electronic device). By being attached, the laminate battery 1 (laminate film 1b) is fixed in a separated state. The arrangement structure of the planar coil 3 will be described in detail later.

  Note that the air core portion of the air core coil constituting the planar coil 3 may be filled with a magnetic material. Such an air core coil is formed, for example, by embedding a magnetic sheet made of a resin in which a soft magnetic material is dispersed in an air core portion. According to the air-core coil, an improvement in the coupling efficiency with the transmission coil provided in the transmitter for wireless power feeding can be expected. Further, the coil shape of the planar coil 3 may be an ellipse or a rectangle other than a circle. When the portable electronic device case 20 has a three-dimensional curved shape, the planar coil 3 may have a three-dimensional curved shape in accordance with the shape of the case. When a magnetic sheet is provided on one surface or the air core of the planar coil 3 as described above, when the battery module is supplied with power by a transmitter for wireless power supply, an improvement in coupling efficiency with the transmission coil provided in the transmitter is expected. it can.

  The coil lead wire 4 is a flexible conductive wire that connects the planar coil 3 and the circuit board 5 and transmits an alternating current generated by the planar coil 3 to the circuit board 5 during wireless power feeding. The coil lead wire 4 may be formed of a member different from the planar coil 3, or may be a single wire of the planar coil 3 or a stranded wire lead. However, since the planar coil 3 is fixed to the inner surface of the portable electronic device case 20 as described above, the coil lead wire 4 that connects the planar coil 3 and the circuit board 5 depends on the size of the portable electronic device itself. A case where the line length becomes longer is also conceivable. In such a case, the coil lead wire 4 may be relayed with another flexible lead wire. Since the coil lead wire 4 has flexibility, a planar coil can be freely arranged. For example, the planar coil can be arranged in a state separated from the laminate film by a predetermined distance. Therefore, it is possible to suitably prevent the eddy current from flowing through the laminated battery, in particular, the metal layer of the laminated film, due to the current generated in the planar coil, so that the reliability of the laminated battery can be improved.

  The circuit board 5 is a circuit for realizing charge control of the laminated battery 1 and power supply control to the portable electronic device. On the circuit board 5, for example, a power receiving circuit 6, a board reinforcing resin portion 7 a, a protection circuit 8, and an FET (Field Effect Transistor) circuit 9 are mounted.

The power receiving circuit 6 is a circuit that receives an alternating current transmitted through the coil lead wire 4 and performs rectification of the alternating current and charging control of the laminated battery 1.
The protection circuit 8 is a circuit that realizes a function for protecting the laminated battery 1. Specifically, the protective circuit 8 detects an overcurrent state of the current received by the power receiving circuit 6, a temperature abnormal state of the laminated battery 1, and the like. , Cut off current, etc.
The FET circuit 9 is a switch circuit that switches between an electrical transmission path when the laminated battery 1 is charged by the battery module 12 and an electrical transmission path when power is supplied to the portable electronic device.

  The board reinforcing resin portion 7 is an insulating resin that is provided at a connection portion between the coil lead wire 4 and the circuit board 5 and covers the coil lead wire 4, and improves the tensile strength of the coil lead wire 4. The board reinforcing resin portion 7a is formed by applying an insulating resin to the circuit board 5 and solidifying it. Here, as the insulating resin, an acrylic UV curable resin may be used when potting is formed, and a polyamide thermoplastic resin may be used when hot-melting is formed. It should be noted that the tensile strength of the terminal lead wire 11 may be improved by providing an insulating resin also at the connection portion of the terminal lead wire 11 with the circuit board 5.

“Manufacturing process of laminated battery”
Next, the manufacturing process of the laminated battery 1 is demonstrated using FIG.
Here, as already described, the laminate film (laminate film 1b) used in the laminate battery 1 is easily damaged by stress concentration when pressed against a very thin and hard protrusion. When assembling the battery module 12 having the configuration shown in FIG. 1, in the conventional structure, the operation of replacing the planar coil 3 with the terminal lead wire 11, the operation of soldering to the circuit board 5, and the application of the substrate reinforcing resin 7a Numerous assembly operations such as solidification operations have to be performed with the laminated battery 1. For this reason, the assembly mechanism using the following circuit unit 13 is employed because the probability that these assembly operations will cause damage such as thermal damage, scratches, pin poles, and dents on the surface of the laminated battery 1 (laminate film) increases.

  As described above, in the circuit unit 13, one end of the coil lead wire 4 is connected to the planar coil 3, the other end of the coil lead wire 4 is connected to the circuit board 5, the circuit board 5 is connected to the terminal lead wire 11, and the connector 10. It is a unit formed in the process of connecting to and integrating. That is, the circuit unit 13 is obtained by unitizing a functional configuration for charging the laminate battery 1 by electromagnetic induction in advance. That is, the adoption of the unit makes it possible to perform a process with a stress load such as heat and stress at the time of manufacturing the battery module 12 separately from the laminated battery 1. Can be eliminated. The battery module 12 is formed through a process of connecting the circuit unit 13 completed in the above process to the negative electrode terminal 14 and the positive electrode terminal 15 of the laminated battery 1. Specifically, the battery module 12 is formed by bringing the circuit board 5 of the circuit unit 13 close to the negative terminal 14 and the positive terminal 15 along the arrow line shown in FIG. In the battery module 12, after the circuit board 5, the negative electrode terminal 14, and the positive electrode terminal 15 are welded, the negative electrode terminal 14 and the positive electrode terminal 15 are folded back, and the welded circuit board 5 is connected to the terrace portion of the laminate film 1b. It is completed by placing it on and fixing it by winding an insulating tape around the terrace.

  Here, since the connection between the circuit unit 13 and the laminated battery 1 is made by welding as described above, there is no scattering of high-temperature solder balls. Therefore, the battery module 12 has a module structure that does not damage the laminated battery 1. Therefore, the battery module 12 uses the mounting mechanism as described above to take advantage of the light weight, thinness, and low cost, which are the characteristics of the laminated battery 1, and further maintain the reliability of the charging function for the laminated battery 1 by electromagnetic induction. However, the cost can also be reduced. The circuit unit 13 is not limited to this configuration, and necessary additions and deletions may be made as appropriate.

“Operation during wireless power transfer and mounting structure in portable electronic devices”
First, the operation at the time of wireless power feeding by the battery module 12 will be briefly described with reference to FIG. FIG. 4 is a circuit block diagram of the battery module according to the present invention.
The planar coil 3 is electromagnetically coupled to an alternating magnetic field transmitted at a resonance frequency or a frequency close to the resonance frequency from a transmission coil in a transmitter for wireless power feeding to generate an alternating current.

  Then, the alternating current generated in the planar coil 3 flows into the circuit board 5 through the coil lead wire 4. The alternating current is supplied to the laminated battery by the negative electrode terminal 14 and the positive electrode terminal 15 connected to the circuit board 5 through the protection circuit 8 and the FET circuit 9 by the power receiving circuit 6 incorporating the rectification function and the charging control function of the secondary battery. 1 is wirelessly powered. The electric power from the laminated battery 1 charged by the power supply is supplied to each part of the portable electronic device via the terminal lead 11 connected to the circuit board 5 through the protection circuit 8 and the FET circuit 9.

Next, the mounting structure of the battery module 12 on the portable electronic device will be described with reference to FIG.
Here, since the planar coil 3 receives an alternating magnetic field at a resonance frequency or a frequency close to the resonance frequency from the transmitter during the wireless power feeding described above and an alternating current flows, the planar coil 3 has a resistance so as not to generate heat. Value and inductance value are managed by wire diameter, number of turns, etc. However, the inductance of the planar coil 3 changes when a metal or the like is present in the vicinity, the coupling coefficient of the wireless power feeding is reduced, resulting in inefficient transmission, and the heat generation of the metal due to its own heat generation and eddy current. Cause the cause.

  Therefore, in the battery module 12 according to the present embodiment as described above, the planar coil 3 is physically separated from the laminated battery 1 including the resin film / metal layer in order to avoid the influence of the metal in the vicinity of the planar coil 3. (Without being attached to the laminate battery 1). Specifically, as shown in FIG. 2, the planar coil 3 has a battery module 12 mounted on a portable electronic device with a thermally conductive double-sided adhesive silicone tape 19 on the inner surface of the portable electronic device case 20. Arranged in a pasted state. For this reason, the planar coil 3 is disposed in a state of being separated from the laminate film 1b including the metal film, so that the influence of heat generation of the metal can be reduced. Further, the heat generated by the planar coil 3 can be radiated from the portable electronic device case 20 to the outside air via the heat conductive double-sided adhesive silicone tape 19. Furthermore, since the space between the planar coil 3 and the laminated battery 1 is filled with air or a resin material having a high thermal resistance, heat conduction to the laminated battery 1 can be avoided. Here, when the distance between the planar coil 3 and the portable electronic device case 20 is about half or more of the diameter of the planar coil 3, the effect of mitigating the influence of heat generation of the metal can be obtained. Therefore, the length of the coil lead wire 4 is determined in advance according to the arrangement size in the portable electronic device case 20. Note that a space between the planar coil 3 and the laminated battery 1 may be appropriately disposed as long as it is a resin component other than metal.

  Here, as a process of incorporating the battery module 12 into the portable electronic device case 20 as described above, the connector 10 is inserted into the circuit of the portable electronic device, and the planar coil 3 is carried via the heat conductive double-sided adhesive silicone tape 19. It is only necessary to stick it to the electronic device case 20. That is, since the battery module 12 is modularized in advance, damage to the laminate film 1b due to the above-described process can be reduced.

  The heat conductive double-sided adhesive silicone tape 19 can be applied to the planar coil 3 in advance, so that the entire coil configuration to be applied to the portable electronic device can be made uniform. In addition, in an environment with little heat generation, in addition to the thermally conductive double-sided adhesive silicone tape 19, for example, an acrylic adhesive is applied to a cushioning polyurethane foam or polyethylene foam as a tape for attaching the planar coil 3. Double-sided tape may be used. Further, when the battery module 12 is transported, damage to the laminate film due to vibration can be reduced by fixing the planar coil 3 and the laminate battery 1 with a low adhesive tape or the like.

(Example 2)
Example 2 of the battery module according to the present invention will be described. Here, in the battery module according to the second embodiment, the same components as those of the battery module according to the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 5, in the battery module 12 a according to the second embodiment, one surface of the planar coil 3 is covered with the magnetic material sheet 2. Here, FIG. 5 is a diagram schematically showing a state before assembly of the circuit unit 13 and the laminated battery 1 according to the present embodiment.

  The battery module 12 a is provided with the magnetic material sheet 2 so as to cover one surface of the planar coil 3. Moreover, in the battery module 12a, the intermediate magnetic sheet 17 is provided in the air core part of the planar coil 3, and the coupling efficiency with the transmission coil is improved.

  The magnetic sheet 2 is made of a resin in which a soft magnetic material is dispersed, and is bonded to the planar coil 3. When the magnetic sheet 2 is bonded to the planar coil 3, the inductance changes due to a change in the distance between the planar coil 3 and the magnetic sheet 2 if the magnetic sheet 2 is not in close contact with the planar coil 3. Can be prevented from changing. The magnetic sheet 2 is connected to a coil lead wire 4 whose end is covered with a sheet reinforcing resin portion b7 covered with a reinforcing resin made of an insulating resin. Since the connection portion between the coil lead wire 4 and the magnetic sheet 2 has the sheet reinforcing resin portion b, the tensile strength of the coil lead wire 4 can be improved. Here, the magnetic sheet 2 has a relative magnetic permeability of 40 or more in order to prevent an eddy current from flowing through the metal layer of the laminate film 1b due to an alternating magnetic field at the time of wireless power feeding and impairing the sealing strength against water. The film thickness is preferably 0.2 mm or more. Moreover, although the relative magnetic permeability of the magnetic material sheet 2 may be 40 or more, it is usually 200 or less from the viewpoint of cost. In addition, since the AC magnetic field generated at the time of wireless power supply is attenuated by the square of the distance, the thickness of the magnetic material sheet 2 can be reduced by the attenuation effect of the AC magnetic field due to the gap between the magnetic material sheet 2 and the laminate battery 1. The cost of the magnetic material sheet 2 can be reduced.

  When the battery module 12a is incorporated in the portable electronic device case 20 shown in FIG. 2, compared to the case where the planar coil 3 alone of the first embodiment is fixed to the inner peripheral surface of the portable electronic device case 20, The distance between the planar coil 3 and the laminated battery 1 can be reduced.

  In addition, since the battery module 12 is modularized in advance in the process of incorporating the battery module 12 into the portable electronic device case 20 as in Example 1, damage to the laminate film 1b due to the above process can be reduced. Furthermore, the heat generated by the planar coil 3 can be radiated from the portable electronic device case 20 to the outside air via the thermally conductive double-sided adhesive silicone tape 19. Further, since the space between the magnetic sheet 2 bonded to the planar coil 3 and the laminated battery 1 is covered with air having high thermal resistance, heat conduction to the laminated battery 1 can be avoided. The battery module 12a adopting the structure of the present embodiment can be manufactured at low cost, can increase the cumulative number of times of wireless power feeding, and can extend the product life.

  In addition, it is desirable to apply the heat conductive double-sided adhesive silicone tape 19 to the surface of the planar coil 3 to which the magnetic material sheet 2 is not bonded in advance because workability to be attached to a portable electronic device can be improved.

(Example 3)
Example 3 of the battery module according to the present invention will be described. Here, in the battery module according to Example 3, the same components as those of the battery module according to the above-described example are denoted by the same reference numerals, and the description thereof is omitted. 6 is a diagram schematically illustrating the battery module 12b according to the present embodiment, and FIG. 7 is a cross-sectional view taken along the line AA in FIG. 6 in a state where the battery module 12b is mounted on a portable electronic device. It is the longitudinal cross-sectional view along. In FIG. 7, the portable electronic device case 20 is omitted.

  As shown in FIG. 6, in the battery module 12 b according to Example 3, the planar coil 3 bonded to the magnetic sheet 2 is bonded to the laminated battery 1 with the magnetic sheet 2 and the spacer sheet 16 interposed therebetween. It consists of a structure. That is, the surface of the magnetic sheet 2 on which the planar coil 3 is not disposed is bonded to the laminate battery 1. Since the planar coil 3 is disposed at a fixed position, the coil lead wire 4 connected to the planar coil 3 is less likely to jump out and is easy to handle. In addition, since the planar coil 3 and the laminated battery 1 can be handled integrally, replacement maintenance is facilitated even when incorporated in a portable electronic device.

  The magnetic sheet 2 is made of a resin in which a soft magnetic material is dispersed, similarly to the magnetic sheet according to the second embodiment, and is formed on the upper surface of the laminated battery 1. The magnetic sheet 2 is formed in the same outer shape as the upper surface of the laminated battery 1, so that the reference position when the planar coil 3 is attached to the magnetic sheet 2 can be easily matched with the outer shape of the laminated battery 1.

The spacer sheet 16 has a through hole larger than the outer shape of the planar coil 3 and is laminated on the magnetic material sheet 2. That is, the planar coil 3 according to the third embodiment is bonded to the magnetic sheet 2 in a state where the planar coil 3 is embedded in the through hole of the spacer sheet 16 as shown in FIG. Here, the thickness of the spacer sheet 16 is the same as the thickness of the planar coil 3. Therefore, since the spacer sheet 16 and the planar coil 3 form a flat surface on the upper surface, the area of the fixed surface can be increased, and the adhesive force when pasting on the portable electronic device is not impaired.
The spacer sheet 16 may be formed of an appropriate resin material such as vinyl chloride or polyethylene terephthalate, but preferably has insulating properties.

(Modification 1)
A modification 1 of the battery module according to the third embodiment will be described. Here, in the battery module according to Modification 1, the same components as those of the battery module according to the above-described embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 8 is a longitudinal sectional view showing a schematic configuration of a battery module 12c according to this modification. This modification is different from the battery module according to Example 3 in that the magnetic material sheet 2 c covers the outer surface of the laminated battery 1.

  In FIG. 8, the flat surface 21 (flat surface) which comprises the laminate film 1b is a surface used as the return | turnback base point of the adhesive seal part of a side surface when the laminated battery 1 is packed, and flatness is ensured. On the other hand, the laminate film 1b provided on the surface facing the flat surface 21 has a slight bulge in the outer peripheral portion. When the magnetic sheet 2 with the planar coil 3 bonded thereto is bonded to the laminated battery 1, the laminate film 1b is peeled off on the outer peripheral portion for a long time. May occur. Therefore, in the battery module 12c, the magnetic sheet 2 is configured so as to cover the side surface of the laminated battery 1, so that the swelling generated in the outer peripheral portion of the laminated battery 1 can be prevented, and thus stronger adhesion is possible. Furthermore, the structure of the battery module 12c also has an effect of shielding the battery side surface from an alternating magnetic field, and improves the reliability of the laminated battery 1 due to heat generation.

(Modification 2)
A second modification of the battery module according to the third embodiment will be described. Here, in the battery module according to Modification 2, the same components as those of the battery module according to the above-described embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 9 is a longitudinal sectional view schematically showing the configuration of the battery module 12d according to this modification. This modification is different from the battery module according to the third embodiment in that the magnetic sheet 2 is bonded to the bottom surface side of the laminated battery 1.

  As shown in FIG. 9, the battery module 12 d is a flat surface in which the planar coil 3 bonded to the magnetic sheet 2 is a surface that serves as a turning point of the adhesive seal portion of the laminated battery on the outer peripheral surface of the laminated battery 1. It has a structure in which the magnetic sheet 2 is sandwiched on the 21 side. Reliable and strong adhesion can be realized by sticking the magnetic sheet coated with the planar coil to the flat surface that is the folding base point of the adhesive seal portion of the laminate film. Here, as in Example 3, the spacer sheet 16 has the same thickness as the planar coil 3. Therefore, since the bottom surface of the spacer sheet 16 and the bottom surface of the planar coil 3 form a flat surface, the flat surface and the flat surface 21 with which flatness is ensured are adhered to each other, thereby helping each other and improving reliability. A strong adhesion with a certain level is realized. It should be noted that the heat conductive double-sided adhesive tape such as the heat conductive double-sided adhesive silicone tape 19 is attached in advance to the spacer sheet 16 and the planar coil 3, so that the battery module 12d can be easily incorporated into a portable electronic device. Become.

  The battery module 12d in this modification is formed by bonding the magnetic material sheet 2 to the planar coil 3 in advance and further attaching a spacer sheet 16 to the upper layer of the magnetic material sheet 2. In the battery module 12d, the function of charging by electromagnetic induction is unitized in advance as the circuit unit 13 as in the first embodiment. That is, a process with a stress load such as heat and stress at the time of manufacturing the battery module 12 is performed separately from the laminated battery 1. Therefore, the same effect as that of the first embodiment can be obtained in this modification.

  The magnetic sheet 2 in this modification is for preventing the eddy current from flowing in the metal layer of the laminate film 1b of the laminate battery 1 due to the alternating magnetic field at the time of wireless power feeding, and the sealing strength against water being impaired. The relative permeability is preferably 80 or more, and the film thickness is preferably 0.5 mm or more. When it is desired to reduce the thickness of the battery module 12, a relative permeability of 160 and a film thickness of 0.25 mm may be selected.

  Next, a state in which the battery module 12d according to this modification is incorporated in a portable electronic device will be described. Here, FIG. 10 is a longitudinal sectional view schematically showing the configuration of a portable electronic device incorporating the battery module 12d according to the present modification. In addition, the code | symbol 22 shown in FIG. 10 is a system circuit part for implement | achieving the control function of a portable electronic device.

  As shown in FIG. 10, the battery module 12 d is fixed to the inner surface of the portable electronic device case 20 via a heat conductive double-sided adhesive silicone tape 19. Here, the laminated battery 1 incorporated in the portable electronic device may have a change in thickness over time, so that it is necessary to secure a space between the system circuit unit 22 and the laminated battery 1. That is, the laminated battery 1 swells when gas is generated inside the portable electronic device case 20 even on a flat surface when the battery is manufactured. This swelling starts on the opposite side of the flat surface 21 of the laminated battery 1. Therefore, by securing a space between the system circuit unit 22 and the laminated battery 1, bulges due to expansion can be concentrated on the opposite side of the planar coil 3 (that is, the flat surface 21 side). As described above, the planar coil can be arranged in a state of being separated from the laminate film constituting the laminated battery, and the influence of heat generated by the planar coil can be reduced.

  As described above, according to the battery module 12d according to this modification, even when the distance between the planar coil 3 and the laminated battery 1 cannot be sufficiently obtained by combining the magnetic sheet 2, the planar coil 3 and the magnetic sheet 2 A battery module in which the laminated battery 1 is integrated can be provided.

That is, the battery module 12d can be assembled in accordance with the structure of the portable electronic device, and becomes a highly reliable battery module by reducing heat generation due to an alternating magnetic field.
Therefore, the present invention can provide a battery module that realizes wireless power feeding of a portable electronic device with high quality and low cost.

  Furthermore, even when the battery module according to the present invention is incorporated into a portable electronic device, it is possible to easily incorporate an AC magnetic field by securing a sufficient distance between the planar coil and the laminated battery simply by fixing the planar coil and inserting a connector. It is possible to reduce the heat generation due to, and to reduce the damage caused by the built-in laminate battery. Similarly, even when the distance between the planar coil and the laminated battery is not sufficient, a module in which the planar coil, the magnetic sheet, and the laminated battery are integrated and the planar coil, the magnetic sheet, and the laminated battery are integrated can be provided. Incorporation is possible according to the structure of the device, and a highly reliable battery module is obtained by reducing the heat generation of the planar coil by the AC magnetic field and the heat generation of the laminated battery. Therefore, the present invention can provide a battery module that realizes wireless power feeding of a portable electronic device with high quality and low cost.

12, 12a, 12b, 12c, 12d Battery module 1 Laminated battery 1a Electrode body 1b Laminating film 2 Magnetic sheet 3 Planar coil 4 Coil lead wire 5 Circuit board 6 Power receiving circuit 7a Board reinforcing resin part 7b Sheet reinforcing resin part 8 Protection circuit 9 FET circuit 10 Connector 11 Terminal lead wire 13 Circuit unit 14 Negative electrode terminal 15 Positive electrode terminal 16 Spacer sheet 17 Medium magnetic sheet 19 Thermally conductive double-sided adhesive silicone tape 20 Portable electronic device case 21 Flat surface 22 System circuit part

Claims (12)

Producing a circuit unit comprising a planar coil, a circuit board, a coil lead member for electrically connecting the planar coil and the circuit board, and a terminal lead member connected to the circuit board;
Welding the circuit board of the circuit unit with a negative electrode terminal and a positive electrode terminal of a laminated battery;
The manufacturing method of the battery module characterized by comprising. The method for manufacturing a battery module according to claim 1, wherein a magnetic sheet is disposed on one surface of the planar coil. The planar coil, the air-core section penetrating in the thickness direction, a manufacturing method of the battery module according to claim 1 or 2 characterized by having a said air-core magnetic body is embedded in the unit sheet. A part of the coil lead member is connected to the magnetic sheet of the planar coil,
The battery module manufacturing method according to claim 2 , wherein a connecting portion between the coil lead member and the magnetic sheet has a sheet reinforcing resin portion covered with a reinforcing resin made of an insulating resin. The connecting portion of the coil lead member and the circuit board, battery according to any one of claims 1-4, characterized in that it comprises a substrate reinforcing resin portion which is covered with the reinforcing resin formed from an insulating resin Module manufacturing method . 5. The battery module manufacturing method according to claim 2 , wherein a surface of the magnetic sheet on which the planar coil is not disposed is bonded to the laminated battery. 6. The battery module manufacturing method according to claim 6 , wherein an outer shape of the magnetic sheet is the same as an outer shape of the laminated battery. The magnetic sheet is laminated with a spacer sheet having a through hole,
The method of manufacturing a battery module according to claim 6 , wherein the planar coil is disposed in the through hole. The method of manufacturing a battery module according to claim 6 , wherein the magnetic sheet covers up to a side surface of the laminated battery where the magnetic sheet is bonded. The magnetic material sheet coated on the planar coil, any claim 7-9, characterized in that affixed to the surface to be the folding base point of the adhesive sealing portion of the laminate battery of the outer peripheral surface of the laminate battery A method for producing the battery module according to claim 1 . The method for manufacturing a battery module according to claim 8 , wherein the spacer sheet is fixed to a portable electronic device case via a thermally conductive double-sided adhesive tape. Battery module manufactured by the method according to any one of claims 1 to 5 A method of manufacturing a portable electronic device which is fixed to the inner wall surface of the casing,
The method of manufacturing a portable electronic device , wherein the planar coil is fixed to another inner wall surface different from the inner wall surface to which the laminated battery is fixed via a heat conductive double-sided adhesive tape.

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