JP3282859B2 - Power supply - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device mounted on an electric device such as a portable wireless device or a personal computer which can be carried independently from a charging device, and a detachable and detachable electric device. The present invention relates to a secondary battery pack and a charging device used for charging a secondary battery.

[0002]

2. Description of the Related Art Various types of electrical equipment that can be carried and used independently of a charging device and used as they are, for example,
Portable radios and notebook computers have been put into practical use.
Many of the power supply devices mounted on these electric devices adopt a form in which a secondary battery is fixed in the electric device, or a form in which a secondary battery pack containing a secondary battery is detachably attached to the electric device. In the latter, a power supply device is constituted by a secondary battery pack and a circuit portion in an electric device. For charging these secondary batteries, a charging device capable of quick charging can be used.

[0003] A charging device capable of quick charging is generally
It is a stationary type connected to a household 100V power supply,
For example, quick charging of a secondary battery is performed without using a power supply device or a secondary battery pack from an electric device in a state where the electric device is connected to the charging device by using the time when the electric device is not used.

[0004] A general recharging process is, for example, a rapid charging process of supplying a constant current of a magnitude enough to charge the entire capacity of the secondary battery within 30 minutes to the secondary battery, and charging the secondary battery.
A normal charging step of supplying a constant current of a magnitude enough to charge the entire capacity of the secondary battery in 5 to 8 hours to the secondary battery and charging the battery, which is performed subsequent to the quick charging step; The transition from to the normal charging process is performed when the charging voltage detection circuit built in the charging device detects a decrease in the charging voltage called -ΔV.

[0005] The decrease in charging voltage called -ΔV is a peculiar phenomenon observed in the charging of a limited type of secondary battery such as a nickel-cadmium battery, and is relatively small from the state of completion or halfway of discharging. When charging the secondary battery with a large constant current, the charging voltage gradually increases, but the internal resistance of the secondary battery temporarily decreases with the completion of regeneration of the active material inside the secondary battery. This is a phenomenon in which a slight decrease in charging voltage is suddenly observed immediately before completion of charging.

[0006] In the case of a nickel-cadmium battery having a capacity of 600 mAh, rapid charging is performed, for example, through a constant current of 600 mA. Switch to

However, depending on the discharge history of the secondary battery, long-term storage after discharge, temperature environment at the time of charging, etc., an apparent -ΔV may not be detected when charging is completed. If the completion time of the quick charge depends only on the detection of -ΔV, the secondary battery may be damaged and cannot be reused.

That is, when the secondary battery in which the regeneration of the internal active material has been completed is left as it is and rapid charging is continued, the supplied electric power is directly converted into Joule heat in the secondary battery, causing internal heat generation. The internal pressure of the next battery rises,
The electrode structure inside the secondary battery may be damaged.

Therefore, the charging device is provided with a timer, and for a fixed time after the start of the quick charging, the charging is forcibly switched to the normal charging even if -ΔV is not detected. As a result, even if the detection of -ΔV fails, the quick charge is terminated before the secondary battery falls into a dangerous state.

[0010]

The electric device equipped with the secondary battery pack can be used during the period in which the quick charging is performed by connecting the electric device to the charging device. If the load on the device side is kept connected, there is a possibility that a false detection of -ΔV may occur on the charging device side. When current is drawn to the load side from the secondary battery pack during quick charging, or when a part of the current for quick charging is drawn to the load side, the load resistance of the power supply unit viewed from the charging device side. And the charging voltage decreases. If this voltage drop is erroneously recognized as -ΔV on the charging device side, even if the charging of the secondary battery is insufficient, the rapid charging is stopped at that point.

In the case of normal charging, when the current consumption of the load is large, the amount of discharge becomes larger than the amount of charge.
The charging may be stopped with insufficient charging.

Therefore, in the conventional electric equipment, the secondary battery pack is detached from the electric equipment, and rapid charging is enabled only in a state where the secondary battery pack alone is loaded in the charging device, and the electric equipment incorporates the secondary battery. When charging is performed in a charged state, only normal charging with a reduced charging current has been performed. However, with normal charging alone, the time required to complete the charging of the secondary battery reaches 4 to 5 times that of rapid charging, resulting in impairing the practicality of the electric device.

Therefore, a switch mechanically operated by an operation of connecting the electric device to the charging device is provided on the electric device side, and the switch disconnects the secondary battery pack from the load in a state where the electric device is connected to the charging device. A solution was considered. That is, during the period when the electric device is connected to the charging device, the electric device cannot be used, so that when charging the secondary battery pack alone, the load conditions are aligned, and the charging voltage decreases as viewed from the charging device side. Do not wake up.

However, in this solution, when normal charging is performed subsequent to rapid charging, the electric device is completely charged until the period of normal charging, which has no effect even when the electric device is operated (no need to detect -ΔV). Becomes unusable. For example, in a portable wireless device, it is desirable that an urgent call can be detected even during a charging period, and a state in which a response to the call can be continued. In portable radios, it is therefore desirable to be able to notify the operator of the call signal at least during the normal charging, and preferably also during the rapid charging, and to be able to perform radio reception and transmission even if charging is interrupted, if necessary. .

Providing a mechanically operated switch on the side of the electrical equipment increases the design constraints of the electrical equipment. For example, in the case of a portable wireless device, a secondary battery pack is detachably mounted on a wireless device main body, and a secondary battery pack portion is inserted into a recess provided in a charging device, and a bottom portion of the secondary battery pack is inserted. Charging is performed through the electrodes provided in the. In this example, even the secondary battery pack removed from the wireless device main body can be charged in the same posture by inserting it into the same recess of the charging device.
However, in this example, it is necessary to provide a mechanically operated switch at the bottom of the secondary battery pack, not at the wireless device main body, and the mounting volume of the switch can be accommodated in a secondary battery pack of the same volume. Reduce the volume of the secondary battery.

[0016] Mechanically actuated switches are generally
The cost is high, and the mounting structure and wiring of the switch are constraints on the miniaturization of the entire electric device, which impairs the portability and operability of the electric device. If the type of charging is restricted, the compatibility with the conventional secondary battery pack is impaired.

It is an object of the present invention, despite the fact that electrical equipment can be at least partially used throughout the charging period,
This is one of the embodiments of the power supply device, in which there is no fear of erroneously detecting ΔV on the side of the charging device, and therefore, there is no fear of ending quick charging or normal charging while the secondary battery is insufficiently charged. It is an object of the present invention to provide a secondary battery pack and a charging device that charges the power supply device.

[0018]

FIG. 1 is an explanatory diagram of a basic configuration of the present invention. In FIG. 1, a power supply device according to claim 1 includes a charging electrode 21 provided in correspondence with a power supply electrode 11 disposed in a charging device 10 that detects a decrease in charging voltage and completes charging, and the charging electrode And a secondary battery 22 connected in series to the battery 21. The secondary battery 22 can be charged by the charging device 10 in a state where power can be supplied to the load 30 from the secondary battery 22. Power supply device 20 in which rapid charging is performed.
And a receiving electrode 23 that receives an electric signal indicating that charging is in progress from the charging device 10 in a connected state of the charging device 10 and
During the period when the receiving electrode 23 is receiving the electric signal, the power supply from the secondary battery 22 to the load 30 causes a voltage drop that exceeds at least the detection level of the charging voltage drop in the charging device 10. And a power saving means 24 for suppressing the power consumption to an unacceptable level.

[0019]

[0020]

[0021]

[0022]

According to the first aspect of the present invention, at least during the charging, the power saving means suppresses the current flowing from the secondary battery to the load, or the current supplied from the charging device and flowing to the load. And the charging device 10
The decrease in the terminal voltage of the secondary battery 22 as viewed from the side is suppressed to at least the level detected as −ΔV. This suppression is performed, for example, in such a manner that a part of the charging current supplied from the charging device 10 is usually consumed by a resistor or the like, and when power is required on the load side, the operation of switching from the resistor to the load is performed. May be realized.

One example of the current suppression is to turn off the supply current to the load 30 and keep the function of the load 30 completely stopped while the power supply is connected to the charging device 10.

By avoiding erroneous detection of -ΔV due to the operation of the load 30 during charging, it is not necessary to oblige the operator to turn off the power switch at the start of charging. Also,
In the state where the charging device 10 is connected to the charging device 10 after the charging is completed, the operation of the load 30 that is not noticed by the operator causes an unexpected consumption of the storage capacity of the secondary battery 22, and the operator determines that the charging is completed and determines that the charging device 10 is completed. It is also possible to avoid a situation where the residual capacity is actually small when the connection to is released.

The fact that the battery is being charged is recognized by receiving the electric signal transmitted from the charging device 10 by the power saving means 24 via the receiving electrode 23. Receiving electrode 23
Performs the transfer of an electric signal indicating that charging is in progress to the power supply device.

The operation of connecting the power supply device 20 to the charging device 10 simultaneously connects the receiving electrode 23 and the charging electrode 21 to the corresponding electrodes (13, 23) on the charging device 10 side, respectively.

The receiving electrode 23 is preferably arranged adjacent to the charging electrode 21 and has the same dimensions and shape as the charging electrode 21. This configuration includes mounting of the receiving electrode 23 in the power supply device 20 and the signal electrode 1 in the charging device 10.
3 facilitates the mounting of the power supply device 20 and further ensures the contact between the receiving electrode 23 and the signal electrode 13 when the power supply device 20 is connected to the charging device 10.

The charging device 10 outputs a constant current large enough to charge the entire capacity of the secondary battery in about 30 minutes, for example, to charge the secondary battery 22 and to change the output voltage of the secondary battery 22. It is detected every moment as a terminal voltage and memorized,
The current output voltage value is compared with the previous value, and charging is stopped when a voltage drop that can be regarded as −ΔV is confirmed.

[0029]

[0030]

[0031]

[0032]

FIG. 2 is an explanatory diagram of a charging system for a portable wireless device according to an embodiment. Here, in a state where the wireless device main body 80 is inserted into the recess 39 of the charger 40, rapid charging of the secondary battery 61 of the battery unit 60 connected to the wireless device main body 80 is performed.

In FIG. 2, the wireless communication device main body 80 has a terminal 8
3, 84, 85 and terminals 63, 64, 65
0 can be separated. The battery unit 60 includes the charging electrode 6
A nickel-cadmium battery 61 is connected in series between 7 and 68, and outputs are taken out from both ends of the nickel-cadmium battery 61 to terminals 63 and 64. The receiving electrode 69 for receiving an electric signal indicating that charging is in progress from the charger 40 is connected to the terminal 6.
Connect directly to 5.

The radio unit 80 modulates the operator's voice signal into a radio signal and transmits the signal from the antenna 90.
1 and a receiving unit 82 that demodulates an external radio signal received through the antenna 90 into an audio signal, activates a speaker, and reproduces audio. The switch 91 turns on and off the power supply of the whole wireless device main body 80.

The transmission power supply 86 supplies power to the transmission section 81 to operate its oscillator, amplification circuit, modulation circuit and the like. The reception power supply 87 supplies power to the reception unit 82 to operate the reception circuit, the modulation circuit, the audio amplification circuit, and the like.

The one-chip microcomputer 89 transmits the transmission unit 81 in response to an operator's switch operation in a normal use state in which the wireless device main body 80 is removed from the charger 40.
And the receiving unit 82 are alternately switched. Microcomputer power supply 88
Supplies power to the one-chip microcomputer 89.

The one-chip microcomputer 89 is also connected to the charger 40 while the switch 91 is turned on while the wireless device main body 80 is connected to the charger 40, that is, the receiving terminal 6.
9, a transmission power supply 86, a power supply 86,
By controlling the receiving power supply 87, the functions of the transmitting unit 81 and the receiving unit 82 are completely stopped. The power consumption of the entire wireless device main body 80 is reduced to the power consumption level of the one-chip microcomputer.

In FIG. 2, a charger 40 is used for home use.
It is a stationary type equipped with an outlet plug 41 connected to a 00V power supply, and has a recess 39 for inserting the wireless device main body at the time of charging.

The charger 40 includes a transformer 42 for obtaining a DC voltage used in the charger 40, a rectifier 43, a constant voltage circuit 44 for obtaining a constant voltage output for operating an electric circuit in the charger 40, A quick charging circuit 45 for obtaining a constant current output for rapidly charging a nickel-cadmium battery 61
Is provided.

The quick charging circuit 45 detects the voltage of the constant current output for quick charging every moment and continuously stores the voltage, and compares the current voltage value with the stored voltage value. Then, when the voltage drop corresponding to −ΔV is detected, the rapid charging is stopped, and thereafter, a low constant current is output to shift to the normal charging.

The quick charge circuit 45 further measures the time after the start of the quick charge, and if a predetermined time elapses, it is temporarily determined that -Δ
Even if V is not detected, a timer is provided for forcibly stopping rapid charging and switching to normal charging. Thus, even if the part that detects a decrease in the charging voltage fails to detect −ΔV, rapid charging is terminated before the secondary battery enters a dangerous state.

Here, the capacity of the nickel-cadmium battery 61 of the battery section 60 is selected to be 600 mAh, the constant current value for rapid charging is 600 mA, and the constant current value for normal charging is 60 mAh.
mA is selected. Therefore, the discharge of nickel
When the cadmium battery 61 is mounted on the charger 40 and rapid charging is started, -ΔV is detected in about one hour, and normal charging is started.

In the charging system for a portable wireless device of the embodiment configured as described above, the battery unit 60 connected to the wireless device main body 80 with the wireless device main body 80 inserted in the recess 39 of the charger 40. Of the secondary battery 61, the switch 91 may be kept ON during the period from the quick charge to the normal charge. Machine body 80
Stops functions other than the power saving operation by the internal one-chip microcomputer 89.

This avoids erroneous detection of -ΔV due to the operation of the transmitting unit 81 and the receiving unit 82 during charging. In addition, after the charging is completed, the transmission unit 81 and the receiving unit 82 are operated while being connected to the charging device 40 to deplete the capacity of the nickel-cadmium battery 61. Avoid situations where the residual capacity is actually small when extracted from

Even if the detection of -ΔV fails in the quick charging circuit 45, the timer stops the quick charging within a certain period of time, so that the secondary battery does not fall into a dangerous state. .

In the embodiment of FIG. 2, most of the functions of the radio main unit 80 are stopped. However, a portion with low power consumption is selected so that the radio main unit 80 can be used for a limited time during charging. Is also good. While the transmission function requires a large current of 1.2 to 1.3 A, reception wait state (squelch state)
Is maintained at 10 to 50 mA or less. Therefore, if only the reception waiting state is maintained and the operator is notified of the reception, it is not necessary to cause a decrease in the charging voltage that is erroneously detected as -ΔV.

In the portable wireless device of such a modified example, the transmission power supply 86 shown in FIG.
2 can be turned on and off at the same time while the power is continuously supplied to the reception detection unit 2. Even during the charging period set to the power saving state by a command from the one-chip microcomputer 89, the reception detection unit Only keep it working.

While the switch 91 is turned on, the one-chip microcomputer 89 detects an external call signal to the receiving unit 82 and notifies the operator of the signal while the electric signal is being input through the terminal 85. Leave the function.

The portable wireless device according to the modified example configured as described above has the wireless device body 80 inserted into the charger 40,
The secondary battery 61 of the battery unit 60 is rapidly charged.
Switch 91 is ON throughout the period from quick charge to normal charge
If there is a call to the wireless device main body 80 during this period, the receiving unit 82 of the wireless device main body 80 detects this, and a method of consuming low power (LED blinking, etc.)
Informs the operator that there is a call.

At this time, even during the rapid charging, the operator can withdraw the radio main unit 80 from the charger 40 and perform reception and transmission as usual, and after completing the task, the radio main unit again Insert the battery 80 into the charger 40 to start rapid charging. Even when the quick charge is restarted from the halfway discharge state, the power saving control by the one-chip microcomputer 89 does not cause erroneous detection of -ΔV in the quick charge circuit 45, and the inside of the nickel-cadmium battery 61 is not changed. The quick charge is continued until the active material is regenerated and a real -ΔV is detected.

[0051]

According to the power supply apparatus of the first aspect, even during charging, the charging apparatus does not erroneously detect -ΔV,
Electrical equipment can be used, at least in part. Partial use is, for example, in the case of a portable wireless device, detection of a low-power-consumption paging radio signal, identification of a caller, storage and retention, and time, excluding high-power-consumption parts such as radio wave oscillation and sound reproduction. And functions such as temperature measurement. In the case of a notebook computer, it is used for functions other than the disk drive and the screen display.

Accordingly, rapid charging is stopped in a state of insufficient charging, and there is no fear that a secondary battery in an insufficiently charged state is mistaken for completion of charging, and the secondary battery can be used to its full capacity every time. In addition, since the electric device is operated during charging, the practical use efficiency and practicality of the electric device are improved.

Further, since the signal electrode can be mounted together with the charging electrode which is originally required to be arranged on the surface of the electric device, an additional mounting electrode is required as compared with the case where a mechanically operated switch is mounted. And the wiring structure is simplified. Therefore, restrictions on the design of the electric device are reduced, which is advantageous for reducing the size and thickness of the entire electric device.

Furthermore, the operation of connecting to the charging device ensures the connection of the signal electrode together with the charging electrode which is originally required to be connected, so that there is no risk of erroneous operation at the start of charging. In addition, since the appearance of the power supply unit-side portion (such as the structure for inserting a secondary battery pack) connected to the charging device can be the same as that of a conventional charging device, a conventional charging device that cannot perform rapid charging or a conventional charging device that does not have a signal electrode. There is no problem in compatibility with the secondary battery pack.

[0055]

[0056]

[0057]

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a basic configuration of the present invention.

FIG. 2 is an explanatory diagram of a charging system of the portable wireless device of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Charging device 11 Power supply electrode 12 Quick charging circuit 13 Signal electrode 14 Signal generating means 20 Power supply device 21 Charging electrode 22 Secondary battery 23 Receiving electrode 24 Power saving means 30 Load

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H02J ⁷ /00-7/12 H02J 7/34-7/36 H01M 10/44

Claims (1)

(57) [Claims] 1. A charging electrode (21) provided corresponding to a power supply electrode (11) disposed in a charging device (10) that detects a decrease in charging voltage and completes charging, and a charging electrode (21). And a secondary battery (22) connected in series to the charging device (21) in a state where power can be supplied to the load (30) from the secondary battery (22). A power supply (2) capable of charging the secondary battery (22)
0) In the connection state of the power supply device (20) and the charging device (10) where the quick charging is performed, the receiving electrode (23) receiving an electric signal indicating that charging is in progress from the charging device (10) side.
And supplying power from the secondary battery (22) to the load (30) during the period when the receiving electrode (23) is receiving the electric signal, by at least the charging voltage of the charging device (10). A power supply device, comprising: power saving means (24) for suppressing a voltage drop exceeding a detection level of the voltage drop so as not to occur.