JPH10248171A - Power supply device and portable terminal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the faulty connection and the like of a connecting terminal and enable the proper discharge of a secondary battery, by so constituting a power supply that the power supply can be detached from an external load, and supplying power to charge the secondary battery to the external load by electromagnetic induction. SOLUTION: The oscillation circuit section 4a of a power supply converts a direct-current voltage output from a secondary battery 3 into a sine-wave voltage V1 at approx. 100kHz, and outputs it to the primary coil 4c of the power supply. The secondary coil 5b of a portable terminal device 5 converts an electromagnetic wave input from the primary coil 4c of the power supply into a voltage by electromagnetic induction, boosts the voltage, and outputs the boosted voltage from the secondary coil 5b to a control circuit section 5c. The control circuit section 5c smoothes the input boosted voltage to generate a smoothed voltage V2, controls the smoothed voltage V2 and thereby obtains a stable output voltage. The control circuit section 5c then supplies this voltage to an external load 5a. Thereby the faulty connection of a connecting terminal is prevented and the secondary battery 3 is properly discharged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a power supply device,
More specifically, the present invention relates to a power supply device that supplies an output voltage of a secondary battery to an external load.

[0002]

2. Description of the Related Art Recently, storage batteries (secondary batteries) have become widespread, and in particular, lithium ion secondary batteries have become widespread. Such a lithium ion secondary battery uses a metal lithium as a negative electrode instead of a conventional lithium battery,
This is a battery system using a carbon material or a transition metal cargokenite in which lithium ions are present in the negative electrode. In this type of battery, a coin-shaped battery using vanadium pentoxide (V2O5) as a positive electrode and carbon (C) as a negative electrode was put into practical use in 1989.
A lithium cobalt oxide (LiCoO2) / carbon (C) battery was put into practical use in 991, and research and development are being actively conducted along with business development.

[0003] A lithium ion secondary battery has an operating voltage that is about three times that of a conventional NiCd battery or nickel-metal hydride battery, which is a power supply for driving portable electronic equipment.
It has high volumetric energy density and about twice the energy density by weight. That is, when compared with batteries having the same energy, the batteries are small and light. In particular, taking advantage of this light feature, lithium ion secondary batteries have been adopted as power supplies for driving cellular phones, video cameras, and notebook computers.

In general, a secondary battery is generally made of a steel outer can with an electrode formed by winding a sheet-like cathode plate through a separator, covered with a cap, and the cap and the outer can are mechanically mounted. Alternatively, it has a structure in which it is firmly adhered by a laser or the like. The terminal electrode for extracting electricity to the outside has a structure in which the negative electrode is an outer can and the anode is a cap, and the metal terminal is directly exposed. Further, recently, a power supply device for charging a secondary battery by an electromagnetic induction method has been developed and is in a practical stage.

[0005]

However, as described above, in the conventional secondary battery, since the terminal electrodes of the battery are formed of metal and exposed to the outside, the terminal electrodes are oxidized or stained. As a result, there are problems such as an increase in contact resistance, a connection failure, and a short circuit of a battery due to a short circuit of a terminal. Further, a power supply device for charging a secondary battery by an electromagnetic induction method has a problem that terminals are not exposed, but must be configured integrally with a load, and the versatility of the power supply device is impaired.

SUMMARY OF THE INVENTION An object of the present invention is to provide a general-purpose power supply device and a portable terminal device capable of preventing a connection failure of a connection terminal or the like and appropriately discharging a secondary battery.

[0007]

A power supply device according to the first aspect of the present invention is a power supply device having a secondary battery and charged by an electromagnetic induction method, and is configured to be detachable from an external load. The above problem is solved by supplying the electric power charged in the secondary battery to the external load by an electromagnetic induction method.

That is, according to the first aspect of the present invention, since the secondary battery is not in contact with the external load (terminalless), connection failure of the connection terminal and destruction of the secondary battery due to short-circuit of the connection terminal are prevented. This can be prevented. In addition, since the external load and the power supply device including the secondary battery are configured separately, there is an effect that the power supply device has versatility.

The power supply according to the second aspect of the present invention is
A coil for converting electromagnetic waves into electrical energy, a charging circuit for smoothing electrical energy changed by the coil, and charging the smoothed electrical energy to a secondary battery; and electrical energy charged to the secondary battery And an oscillating circuit for converting the electric power into AC electric energy and outputting the converted electric energy to the coil.

Therefore, since the secondary battery and the external load are not in contact with each other (terminalless), it is possible to prevent connection failure of the connection terminal and breakage of the secondary battery due to short-circuit of the connection terminal. In addition, since the external load and the power supply device including the secondary battery are configured separately, there is an effect that the power supply device has versatility.

According to a third aspect of the present invention, there is provided a secondary battery which is charged by an electromagnetic induction system and is detachably attached to the portable terminal device. Is supplied with power.

Thus, since the secondary battery is not in contact with the external load (terminalless), it is possible to prevent connection failure of the connection terminal and breakage of the secondary battery due to short-circuit of the connection terminal. In addition, since the external load and the power supply device including the secondary battery are configured separately, there is an effect that the power supply device has versatility.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view showing a schematic configuration of a power supply device according to the present invention. As shown in FIG. 1, the basic structure of the power supply device 1 includes an outer case 2, a rechargeable battery 3 disposed in the outer case 2, and a rechargeable battery disposed in the outer case 2 at a position facing the rechargeable battery 3. The secondary battery 3 and the charging / discharging circuit 4 are mounted on substantially the same plane.

As the secondary battery 3, a lithium-ion secondary polymer battery which does not generate gas during charging and can be made thinner is optimal. The charge / discharge circuit 4 includes a coil and electronic components. Further, the outer case 2 is made of a non-conductive material such as a resin, and has a structure without a metal external connection terminal on the surface of the case. As described above, a thinner battery is realized by mounting the secondary battery 3 and the charging / discharging circuit 4 on substantially the same plane.

FIG. 2 is a perspective view showing a schematic configuration in which the power supply device 1 is mounted on a portable terminal device (portable telephone) 5 which is an external load.

The power supply device 1 is configured to be detachable from the portable terminal device 5, and any type of mounting means may be used. For example, the power supply device 1 is mounted by screwing or fitting.

The portable terminal device 5 includes an antenna 11 for transmitting / receiving a radio signal, and a liquid crystal display unit 13 for displaying key input contents and various function guidance in a key input unit 12.
And a key input unit 1 including a numeric keypad, a registration key, and the like
2, a receiving speaker 14 for reproducing a receiving voice, a microphone 15 for inputting a transmitting voice, and a speaker 16 for acoustically notifying a user that the user is in a receiving state or a registered position. I have.

FIG. 3 is a block diagram showing a circuit configuration of the power supply device. The power supply device 1 includes the chargeable / dischargeable secondary battery 3 and the charge / discharge circuit 4 as described above.
Is composed of an oscillating circuit 4a, a control circuit 4b, and coils 4c1 and 4c2 that become primary coils during charging and secondary coils during discharging.

The charge / discharge circuit 4 is a circuit for charging and discharging the secondary battery 3, and the structure of the charge / discharge circuit 4 will be described below.

The coil 4c is for transmitting and receiving power without contact by electromagnetic induction. The control circuit 4b smoothes the input of power to the coil 4c,
This is a circuit for preventing overcharging of the battery. Oscillation circuit 4a
Is a circuit for boosting and converting the battery voltage of the secondary battery 3 into a sine wave and outputting it to the coil. The operations of the control circuit 4b and the oscillation circuit 4a are automatically switched by periodically monitoring the voltage across the coil 4c.

Next, the charging / discharging operation of the power supply device will be described.

FIG. 4 is a diagram functionally showing the power supply device for explaining the charging operation of the power supply device 1. FIG.
FIG. 3 is a diagram illustrating voltage waveforms at various parts of the power supply device 1. Hereinafter, an operation at the time of charging the power supply device 1 will be described with reference to FIG.

In FIG. 4, a power supply device 1 includes a charging circuit 6
Is charged. When charging, the coil 4 of the power supply circuit 1
c functions as a secondary coil, and the control circuit 4b operates to charge the secondary battery 3. Oscillation circuit section 6a of charging circuit 6
Outputs an AC voltage of 100 V input from an AC power supply (not shown) into a sine wave voltage V1 of about 100 KHZ as shown in FIG. I do. The secondary coil 4c is a primary coil 6b
Is converted into a voltage by electromagnetic induction and boosted, and the boosted voltage is output to the control circuit 4b. This step-up rate is determined by the winding ratio of the coil. The control circuit unit 4b smoothes the input boosted voltage to generate a smoothed voltage V2 as shown in FIG. 5B, and controls the smoothed voltage V2 to charge the secondary battery 3. Appropriate charging is performed by controlling the voltage.

FIG. 6 is a diagram functionally showing the power supply 1 to explain the discharging operation of the power supply 1. Less than,
With reference to FIG. 6, an operation when the battery is discharged, that is, when the external load 5a such as the portable terminal device 5 is operated by the secondary battery 3 of the power supply device 1 will be described.

As shown in FIG. 6, the portable terminal device 5 includes a secondary coil 5b, a control circuit 5c, and an external load 5a. Then, the coil 4c of the power supply device 1 functions as a primary coil, the oscillation circuit 4a operates, and the secondary battery is discharged.

The oscillation circuit section 4a of the power supply device 1 converts the DC voltage output from the secondary battery 3 into a sine wave voltage V1 of about 100 KHz as shown in FIG. 4c. And 2 of the mobile terminal device 5
The secondary coil 5b converts the electromagnetic wave input from the primary coil 4c of the power supply device 1 into a voltage by electromagnetic induction and boosts the voltage, and boosts the voltage from the secondary coil 5b to the control circuit unit 5c.
Output to

The control circuit section 5c smoothes the input boosted voltage to generate a smoothed voltage V2 as shown in FIG. 5B, and controls the smoothed voltage V2 to provide a stable output. A voltage is obtained, and this voltage is supplied to the external load 5a.

As described above, in the present embodiment, since the secondary battery 3 and the external load 5 are in non-contact (terminalless), connection failure of the connection terminal or destruction of the battery due to short-circuit of the connection terminal. Can be prevented. Further, since the external load 5 and the power supply device 1 including the secondary battery 3 are configured separately, there is no need to provide a booster circuit or the like on the external load 5 side, and the circuit configuration and wiring on the load side can be simplified. It has the effect that it can be done.

Further, in this embodiment, since the secondary battery and the charging / discharging circuit are arranged on the same plane, a thin and highly portable power supply device can be provided.

Further, in the present embodiment, the external load is, for example, a portable terminal device, so that the circuit configuration and electric wiring of the portable terminal device can be simplified.

In the above-described embodiment, a lithium-ion secondary polymer battery is used as a secondary battery, but the present invention is not limited to this, and another secondary battery may be used. Needless to say.

In this embodiment, the portable terminal device is used as the external load. However, the present invention is not limited to this, and the power supply device can be mounted on another external load (for example, a headphone stereo). It goes without saying that it is possible.

[0034]

According to the first, second and third aspects of the present invention, since the secondary battery and the external load are not in contact with each other (terminalless), the connection failure of the connection terminal or the secondary connection due to the short-circuit of the connection terminal is prevented. It is possible to prevent the destruction of the battery. In addition, since the external load and the power supply device including the secondary battery are configured separately, there is an effect that the power supply device has versatility.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic configuration of a power supply device according to the present invention.

FIG. 2 is a perspective view showing a schematic configuration in which a power supply device is mounted on a portable terminal device (mobile phone) 5 which is an external load.

FIG. 3 is a block diagram illustrating a circuit configuration of a power supply device.

FIG. 4 is a diagram functionally showing the power supply device for describing a charging operation of the power supply device.

FIG. 5 is a diagram showing voltage waveforms at various parts of the power supply device.

FIG. 6 is a diagram functionally showing the power supply device for describing a discharging operation of the power supply device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power supply device 2 External case 3 Secondary battery 4 Charge / discharge circuit 4a Oscillation circuit 4b Control circuit 4c Coil 5 External load 11 Antenna 12 Key input unit 13 Liquid crystal display unit 14 Speaker 15 Microphone 16 Speaker

Claims (3)

[Claims] 1. A power supply device having a secondary battery and charged by an electromagnetic induction method, configured to be attachable to and detachable from an external load, and supplying power charged to the secondary battery to the external load by an electromagnetic induction method. A power supply device comprising: a discharge circuit for supplying; 2. A coil for converting electromagnetic waves into electric energy, a charging circuit for smoothing electric energy changed by the coil, and charging the smoothed electric energy to a secondary battery, and charging a secondary battery. A power supply device, comprising: an oscillating circuit that converts the electric energy to AC electric energy and outputs the converted electric energy to the coil. 3. A secondary battery which is charged by an electromagnetic induction method and is detachable from the portable terminal device, and supplies power to a circuit in the portable terminal device by the electromagnetic induction method when the secondary battery is mounted. A portable terminal device characterized by the above-mentioned.