JPH1141828A - Charging and discharging method and device for secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To start charging and discharging after a battery pack recognizes that charging and discharging side is a circuit of normal specification, by starting charging and discharging after the battery pack detects a signal sent continuo usly or intermittently from the charging and discharging side. SOLUTION: On a charging and discharging side 6, a charging control circuit 2 always transmits pulse signals at fixed intervals. When a battery pack 34 is mounted on the charging and discharging aide 6, a change in the cycle and level of the pulse signal is detected by a signal detection circuit 27. A change in current or voltage is determined in advance, and when no change is made or cycle level and the like are different, no charging or discharging is conducted as no recognition is performed at the signal detection cincut 27 that it is an exact charging and discharging circuit. On the other hand, when signal detection circuit 27 recognizes that it is a proper charging and discharging circuit, a detection signal is transmitted to a battery pack side control circuit 33 to turn on a charging switch 28. As a result, the charging control circuit 2 detects energizing, and the recognition of a charging circuit by pulse charging is completed for charging.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging / discharging method for charging / discharging a battery pack using a chargeable / dischargeable secondary battery such as nickel-cadmium, nickel-metal hydride, lithium ion or the like.

[0002]

2. Description of the Related Art Conventionally, in the charging and discharging of secondary batteries such as nickel-cadmium and nickel-metal hydride batteries, the development of the safety of a charger / discharger or a charge pack has not been very active. Lithium ion secondary batteries that are being used have a problem in terms of safety of the substance itself, and research and development for improving safety are being actively conducted in various fields.

FIG. 7 shows a configuration diagram of a battery pack using a conventional lithium ion secondary battery. In this configuration, 6
Reference numeral 1 denotes a charging switch that is closed during charging, and 62 denotes a discharging switch that is closed during discharging. 63
64 is a charging and discharging diode, respectively. 65
Is a charge / discharge switch 61 for charging or discharging.
A current detection circuit for detecting a current flowing through each of the switches 62 and 62. When an abnormal current is detected, the switches 61 and 62 are opened to forcibly stop charging and discharging. 66 is a secondary battery composed of one or more cells, 67 is a voltage detection circuit that detects the voltage of each single cell or a plurality of cells of the secondary battery 66, and switches the switches 61 and 62 when an abnormal voltage is detected. Open and forcibly stop charging and discharging. Reference numeral 68 denotes a thermal fuse such as an electronic switch using an FET, which is opened when the temperature of the charge / discharge switches 61 and 62 rises to a certain level or more, and forcibly interrupts the current. This thermal fuse 68
Since it does not return once it has expired, it needs to be replaced.

The operation principle of this battery pack is as follows. At the time of charging, the charging switch 61 conducts, and charges the secondary battery 66 through the charging diode 63. At this time, the current detection circuit 65 and the voltage detection circuit 6
If an abnormal current or abnormal voltage is detected in step 7, the charging switch 61 is opened to forcibly stop charging. When the temperature of the charging switch 61 rises above a certain level, the temperature fuse 68 is opened and the charging operation is forcibly stopped.

At the time of discharging, the discharging switch 62 is turned on, and the secondary battery 66 is discharged through the discharging diode 64. At this time, when an abnormal current and an abnormal voltage are detected by the current detection circuit 65 and the voltage detection circuit 67, the discharge switch 62 is opened to forcibly stop the discharge. When the temperature of the discharge switch 62 rises above a certain level, the thermal fuse 68 is opened, and the discharging operation is forcibly stopped.

[0006]

However, in the above-mentioned conventional configuration, since the safety measures are provided by the battery pack alone, the battery chargers and notebook computers which do not have the specified specifications or have no safety measures have been taken. However, even if there is a charging / discharging side and a battery pack, they cannot detect each other, and charging / discharging is performed, which may be a cause of failure. Further, when the charging / discharging side or the battery pack side has failed, there is a possibility that the other side may be affected by the failure or the like.

The present invention solves such a conventional problem, and starts charging / discharging after recognizing that the charging / discharging side and the battery pack side operate as a circuit having a proper specification. Accordingly, an object of the present invention is to provide a highly reliable and safe charging and discharging method and device.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a charging / discharging method for charging / discharging a battery pack including at least one cell or more of secondary batteries. This is a charging / discharging method that starts charging / discharging of the battery pack after the battery pack detects a signal that has been transmitted in a specific manner. This allows the battery pack to recognize that the charging / discharging side is a circuit with proper specifications and then charge / discharge the battery. Discharge can be started.

The present invention is also directed to a charge / discharge device that embodies the above-described charge / discharge method. In the charging / discharging device configured with the discharging side, the charging / discharging side is provided with a charging / discharging control circuit that constantly or intermittently transmits a signal, and the battery pack receives the signal transmitted from the charging / discharging side. It comprises a signal detection circuit for detecting, and a battery pack side switch control circuit for receiving a signal from the signal detection circuit and controlling the charging switch and the discharging switch. According to this device, the charge / discharge can be started after the battery pack side recognizes that the charge / discharge side is a circuit of a proper specification.

When the battery pack is mounted on the charging / discharging side, a signal is transmitted from the charging / discharging side to the battery pack after detecting that the battery pack is mounted on the charging / discharging side.
If the charging and discharging method starts charging and discharging the battery pack after the signal is detected by the battery pack, a signal is transmitted only when the charging / discharging side detects the mounting of the battery pack. Can be eliminated.

The present invention is also directed to a charge / discharge device that embodies the above-described charge / discharge method. In a charging / discharging device composed of a discharging side, a charging / discharging side switch for controlling a charging / discharging side switch based on a signal from the battery detecting circuit for detecting that a battery pack is mounted on the charging / discharging side. A control circuit; a charge / discharge control circuit for receiving a signal from the battery detection circuit and transmitting a signal; the battery pack includes a signal detection circuit for detecting a signal transmitted from the charge / discharge control circuit; and a signal detection circuit. And a battery pack-side switch control circuit that receives a signal from the battery pack and controls the charge switch and the discharge switch. Thus, after the charging / discharging side recognizes the mounting of the battery pack, the charging / discharging side can start charging / discharging after the charging / discharging side recognizes that the circuit has the proper specification.

According to another aspect of the present invention, there is provided a battery pack including at least one cell or more of a secondary battery, and a battery pack including a positive electrode, a negative electrode, and an identification terminal. In the charging / discharging device configured to perform charging / discharging, the charging / discharging side includes an identification signal generating circuit that transmits an identification signal to the battery pack. And a battery pack-side switch control circuit that receives a signal from the identification signal detection circuit and controls a charging switch and a discharging switch. Thus, the charging / discharging side can start charging / discharging after the charging / discharging side recognizes that the charging / discharging side is a circuit of the normal specification using the identification terminal.

Further, after the battery pack is mounted on the charging / discharging side, the battery pack detects a signal sent from the charging / discharging side, so that the battery pack can be charged / discharged. If the charging / discharging side detects the signal, the charging / discharging side can be charged / discharged, and the charging / discharging method in which the charging / discharging of the battery pack is started after both the battery pack and the charging / discharging side can be charged / discharged. Charge / discharge can be started after recognizing that the circuit configuration has the proper specification.

According to the present invention, a charge / discharge device embodying the above-described charge / discharge method includes a battery pack including at least one cell or more of a secondary battery, a battery pack including a positive electrode, a negative electrode, and one or more identification terminals. In a charging / discharging device configured with a charging / discharging side that performs charging / discharging, a charging / discharging side identification signal generating circuit that transmits an identification signal to a battery pack and a identification signal sent from the battery pack are detected on the charging / discharging side. A charge / discharge side identification signal detection circuit, and a charge / discharge side switch control circuit that controls a charge / discharge side switch based on a signal from the charge / discharge side identification signal detection circuit, and the battery pack is provided with an identification terminal from the charge / discharge side. A pack-side identification signal detection circuit for detecting the sent identification signal, a pack-side identification signal generation circuit for sending an identification signal to the charge / discharge-side identification signal detection circuit through an identification terminal, and a pack-side identification signal It is obtained and a battery pack side switch control circuit for controlling the charging switch receives a signal from the detection circuit and discharge switch. As a result, charging and discharging can be started after both sides recognize that the circuit configuration has the proper specifications.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings.

(Embodiment 1) A case where the number of connection terminals is two will be described with reference to the configuration diagram of the charge / discharge device of FIG. In FIG. 1, 1 is a power supply circuit for supplying power, and 2 is an ON / O power supply provided by the power supply circuit.
A charge control circuit for controlling the FF and the like, 3 is a current detection resistor for supplying current information to the charge control circuit 2, and 4 and 5 are positive electrodes for connecting the charge / discharge side and the battery pack side, respectively. And a negative electrode. From the power supply circuit 1 to the negative electrode 5
Up to this point, the configuration of the charge / discharge side 6 is not limited to the charger described in this embodiment, and may be an electronic device such as a notebook computer. In that case, the charging / discharging side 6 does not always include the power supply circuit 1, and the charging control circuit 2 needs to be a circuit capable of discharging control.

Reference numeral 27 denotes a signal detection circuit for detecting a pulsed voltage transmitted from the charger / discharger 6 under the control of the charge control circuit 2, reference numeral 28 denotes a charging switch which is closed during charging, and reference numeral 29 denotes a charging switch. This is a discharge switch that is closed during discharge. Reference numeral 30 denotes a charging diode that is passed during charging and prevents a backflow of current, and 31 denotes a discharging diode that is passed during discharging and prevents a backflow of current. Reference numeral 32 denotes a secondary battery composed of one cell or a plurality of cells. Reference numeral 33 denotes an output from the signal detection circuit 27, and switches the charging switch 28 and the discharging switch 29 to O.
This is a battery pack side switch control circuit for N / OFF control. Here, the battery-pack-side switch control circuit 33 performs switch control while also serving as the voltage detection circuit 67 in the conventional example. The structure from the signal detection circuit 27 to the battery pack side switch control circuit 33 is a battery pack side 34.

FIG. 1B is a timing chart of a pulse signal transmitted from the charge control circuit 2.
In the present embodiment, the signal is always transmitted at a constant interval, but the signal may be transmitted constantly or may be transmitted intermittently.

The operation in this configuration will be described with reference to the flowcharts of FIGS. FIG. 2 shows a flow at the time of charging using the charger. Charge / discharge side 6
In, the charge control circuit 2 always transmits a pulse signal at regular intervals. This may be controlled electrically, or may be controlled mechanically using a switch. Then, a pulsed voltage as shown in FIG. 1B is applied to the positive electrode, and supplied from the charge / discharge side 6 to the battery pack side 34. When the battery pack side 34 is mounted on the charging / discharging side 6, a change in the cycle, level, or the like of the DC voltage is detected by the signal detection circuit 27. The current and voltage to be changed are determined in advance, and if there is no change, or if there is a change in the cycle level or the like, the correct charge / discharge circuit is not recognized. When the signal detection circuit 27 recognizes a correct charge / discharge circuit, a detection signal is sent to the battery pack side switch control circuit 33. Then, the battery pack side switch control circuit 33 sets the charging switch 28 to O
When N is set, it is detected that the charging control circuit 2 is energized, and the recognition of the charging circuit by pulse charging ends, and charging starts. Thereby, the battery pack side 34 can be easily configured.
In the above, charging can be started after the charging / discharging side 6 is recognized as having a circuit configuration of regular specifications.

Although the operation at the time of charging has been described here, the flow is substantially the same at the time of discharging when electronic equipment is used. That is, instead of turning on the charging switch 28, the discharging switch 29 is turned on to start discharging.

Although pulse signals of the same shape are sent here, two shapes having different periods or levels are used to distinguish whether a charger or a discharge device such as an electronic device is connected. It is needless to say that it is desirable to send the pulse signal of

(Embodiment 2) In this embodiment,
The description of the components having substantially the same configuration as the first embodiment is omitted, and the same reference numerals are given.

Another embodiment in which the number of connection terminals is two will be described with reference to the configuration diagram of the charge / discharge device of FIG. In FIG. 3A, reference numeral 7 denotes a battery detection circuit for detecting that the battery pack is mounted, and reference numeral 8 denotes a charge / discharge-side switch control circuit for performing ON / OFF control of the charge / discharge-side switch 9. The charge / discharge side switch 9 is electrically operated by the charge control circuit 2 in the first embodiment. In the present embodiment, the configuration on the battery pack side 34 is the same as that used in the first embodiment. FIG. 3B shows a timing chart of a pulse signal transmitted from the charge / discharge side 6 to the battery pack side 34.

The operation in this configuration will be described with reference to FIGS. FIG. 4 shows a flow at the time of charging using the charger. When the battery pack is not attached to the device, the discharging switch 29 is closed. When the battery pack is attached to the charging / discharging side 6, the discharging switch 29 and the discharging diode are connected from the battery pack side 34. A current flows to the charging / discharging side 6 via 31. When this is detected by the battery detection circuit 7, a signal for turning on the charge / discharge side switch 9 is sent from the charge control circuit 2 to the charge / discharge side switch control circuit 8, and the pulse-like voltage is sent from the charge / discharge side 6 to the battery pack side 34. To supply. Since the battery pack side 34 is already mounted, the signal detection circuit 27 detects a change in the cycle and level of the DC voltage. The change of the current and voltage is determined in advance, and if there is no change, or if there is a change in the cycle level or the like, the correct charge / discharge circuit is not recognized. When the signal detection circuit 27 recognizes a correct charge / discharge circuit, a detection signal is sent to the battery pack side switch control circuit 33. Then, the battery pack side switch control circuit 33 is connected to the charging switch 2.
8, when the charging control circuit 2 is turned on, the recognition of the charging circuit by pulse charging is terminated,
Start charging.

The addition of the battery detection circuit 7 eliminates the necessity of constantly transmitting a pulse signal, thereby suppressing unnecessary power consumption and not transmitting a pulse signal as in the first embodiment. Since there is no period t2, a responsive structure can be obtained. Although the operation at the time of charging has been described here, it goes without saying that the flow is substantially the same even when an electronic device is used as in the first embodiment. Needless to say, this wasteful power consumption is particularly effective in the case of a portable electronic device.

Although a pulse signal having a single shape is also sent here, two pulses having different periods or levels are used to distinguish whether a charger is connected or a discharging device such as an electronic device is connected. It goes without saying that it is desirable to send a pulse signal having a shape.

In the first and second embodiments,
Although a pulse signal is used as a signal, the present invention is not limited to this. Needless to say, the legitimacy of the charge / discharge side 6 and the battery pack side 34 may be confirmed by changing a unique voltage.

(Embodiment 3) In this embodiment,
The description of the same configuration as that of the above-described embodiment is omitted, and the same reference numeral is given.

The case where the number of connection terminals is three will be described with reference to the configuration diagram of the charge / discharge device of FIG. In FIG. 5, reference numeral 10 denotes an identification signal generation circuit for transmitting an identification signal to the battery pack side 34 through the identification terminal 11, and the signal is transmitted at a constant interval as shown in the above-described embodiment. Alternatively, it is also possible to attach the detection function of the battery pack side 34 and transmit after the battery pack side 34 is mounted. Reference numeral 35 denotes an identification signal detection circuit which detects an identification signal sent from the signal signal generation circuit 10 through the identification terminal 11 and recognizes the signal as a legitimate charge / discharge side 6 and converts the signal to a battery pack side switch control circuit. Send to 33. Other configurations are the same as those in the first embodiment.

Thus, even in the case of three terminals, it is possible to perform control such that a signal unique to each charger and each electronic device is provided, and the charge / discharge side 6 is recognized using the signal, and then charged / discharged. Becomes

(Embodiment 4) In this embodiment,
The description of the same configuration as that of the above-described embodiment is omitted, and the same reference numeral is given.

The case where the number of connection terminals is four will be described with reference to the configuration diagram of the charge / discharge device of FIG. In FIG. 6, reference numeral 12 denotes a charge / discharge-side identification signal generating circuit for transmitting an identification signal to the battery pack side 34 through the identification terminal 13.
Reference numeral 6 denotes a pack-side identification signal detection circuit for detecting an identification signal sent through the identification terminal 13. Reference numeral 37 denotes a pack-side identification signal generation circuit for transmitting an identification signal to the charging / discharging side 6 through the identification terminal 15, and reference numeral 14 denotes a charging / discharging-side identification signal detection circuit for detecting the identification signal sent through the identification terminal 15. is there.

In this configuration, when the battery pack side 34 is mounted on the charge / discharge side 6, the charge / discharge side identification signal generation circuit 1
When the pack-side identification signal identification signal detecting circuit 36 recognizes that the charging / discharging side 6 is valid based on the identification signal transmitted from 2, the output signal is sent to the battery pack-side switch control circuit 33. As a result, the charging switch 28 or the discharging switch 29 is closed, and the battery pack 34 is ready for charging and discharging.

When the battery pack side 34 is mounted on the charge / discharge side 6, the charge / discharge side identification signal detection circuit 14 is a legitimate battery pack side 34 based on the identification signal transmitted from the pack side identification signal generation circuit 37. , The output signal is sent to the charge / discharge side switch control circuit 8. As a result, the charge / discharge side switch 9 is closed, and the charge / discharge side 6 is ready for charging / discharging. Then, the actual charging / discharging is started after the recognition of both of them, so that the charging / discharging is not performed unless both the charging / discharging side 6 and the battery pack side 34 are legal devices. Therefore, it is possible to make the configuration high in both safety and reliability.

In the present embodiment, the validity of the charging / discharging side 6 is confirmed, but it is needless to say that the same effect can be obtained even if the validity of the battery pack side 34 is confirmed.

Further, in this embodiment, the case where there are two identification terminals is shown, but it is needless to say that the same effect can be obtained by using the identification terminal as one terminal and performing one-wire bidirectional communication.

[0037]

As described in the above embodiment, according to the present invention, by using a battery detection circuit, a signal detection circuit, an identification signal generation circuit, an identification signal detection circuit, and the like, the charging / discharging side and the battery pack side can be used. Since charge / discharge is performed after the validity is recognized, a charge / discharge method and a charge / discharge device capable of improving both safety and reliability can be provided.

[Brief description of the drawings]

FIG. 1A is a configuration diagram of a charging / discharging device according to a first embodiment of the present invention. FIG. 1B is a timing chart of pulse transmission in the first embodiment of the present invention.

FIG. 2 is a flowchart of a charging method according to the first embodiment of the present invention.

3A is a configuration diagram of a charge / discharge device according to a second embodiment of the present invention. FIG. 3B is a timing chart of pulse transmission according to the second embodiment of the present invention.

FIG. 4 is a flowchart of a charging method according to Embodiment 2 of the present invention.

FIG. 5 is a configuration diagram of a charge / discharge device according to Embodiment 3 of the present invention.

FIG. 6 is a configuration diagram of a charge / discharge device according to Embodiment 4 of the present invention.

FIG. 7 is a configuration diagram of a conventional charge / discharge device.

[Explanation of symbols]

 4 Positive electrode 5 Negative electrode 6 Charge / discharge side 7 Battery detection circuit 8 Charge / discharge side switch control circuit 9 Charge / discharge side switch 10, 12, 37 Identification signal generation circuit 11, 13, 15 Identification terminal 14, 35, 36 Identification signal detection circuit 27 Signal detection circuit 28 Charge switch 29 Discharge switch 32 Secondary battery 33 Battery pack side switch control circuit 34 Battery pack side

Claims (7)

[Claims] 1. A charging / discharging method for charging / discharging a battery pack including at least one cell or more of a secondary battery, wherein the battery pack detects a signal constantly or intermittently transmitted from a charging / discharging side. And charging and discharging the secondary battery. 2. A charge / discharge device comprising: a battery pack including at least one cell or more of a secondary battery; and a charge / discharge side for charging / discharging the battery pack with two terminals of a positive electrode and a negative electrode. The battery pack is provided with a charge / discharge control circuit that constantly or intermittently transmits a signal, and the battery pack includes a signal detection circuit that detects a signal transmitted from the charge / discharge side and a signal detection circuit that outputs a signal from the signal detection circuit. A charge / discharge device for a secondary battery, comprising: a battery pack-side switch control circuit that receives a signal and controls a charge switch and a discharge switch. 3. A charge / discharge method for charging / discharging a battery pack including at least one cell or more of a secondary battery, wherein when the battery pack is mounted on the charge / discharge side, the battery pack is charged on the charge / discharge side. A signal is transmitted from the charging / discharging side to the battery pack after detecting that the battery pack is attached, and charging / discharging of the battery pack is started after the battery pack detects the signal. How to charge and discharge the next battery. 4. A charge / discharge device comprising: a battery pack including at least one cell or more of a secondary battery; and a charge / discharge side for charging / discharging the battery pack with two terminals of a positive electrode and a negative electrode. On the side, a battery detection circuit that detects that the battery pack is mounted, a charge / discharge side switch control circuit that controls a charge / discharge side switch by a signal from the battery detection circuit, and a signal from the battery detection circuit. A charge / discharge control circuit for transmitting a reception signal; a signal detection circuit for detecting a signal transmitted from the charge / discharge control circuit in the battery pack; and a charging switch for receiving a signal from the signal detection circuit. A charge / discharge device for a secondary battery, comprising: a battery pack-side switch control circuit that controls a battery and a discharge switch. 5. A charge / discharge device comprising a battery pack including at least one cell or more of a secondary battery, and a charge / discharge side for charging / discharging the battery pack with three terminals of a positive electrode, a negative electrode and an identification terminal, An identification signal generating circuit for transmitting an identification signal to the battery pack on the charge / discharge side, and an identification signal detection circuit for detecting an identification signal sent from the identification signal generation circuit through the identification terminal to the battery pack. And a battery pack-side switch control circuit that receives a signal from the identification signal detection circuit and controls a charge switch and a discharge switch. 6. A charging / discharging method for charging / discharging a battery pack including at least one cell or more of a secondary battery, wherein the battery pack is mounted on the charging / discharging side and then sent from the charging / discharging side. When the battery pack detects a signal, the battery pack can be charged and discharged, and when the charge / discharge side detects a signal sent from the battery pack, the charge / discharge side can be charged / discharged, A charging / discharging method for a secondary battery, wherein charging / discharging of the battery pack is started after both the battery pack and the charging / discharging side are in a chargeable / dischargeable state. 7. A charging / discharging device comprising: a battery pack including at least one or more secondary batteries; and a charging / discharging side for charging / discharging the battery pack with a positive electrode, a negative electrode, and one or more identification terminals. In the charge / discharge side, a charge / discharge side identification signal generation circuit for transmitting an identification signal to the battery pack, a charge / discharge side identification signal detection circuit for detecting an identification signal sent from the battery pack, A charge / discharge side switch control circuit for controlling a charge / discharge side switch based on a signal from a side identification signal detection circuit, wherein the battery pack detects an identification signal sent from the charge / discharge side through an identification terminal. Side identification signal detection circuit, a pack side identification signal generation circuit that sends an identification signal to the charge / discharge side identification signal detection circuit through an identification terminal, and a signal from the pack side identification signal detection circuit. Only discharge device for a secondary battery, characterized by comprising a battery pack side switch control circuit for controlling the charging switch and the discharging switch.