JP4821691B2 - Secondary battery pack - Google Patents

Description

  The present invention relates to a secondary battery pack having a secondary battery block composed of one to a plurality of secondary batteries and a protection circuit, and more particularly to a secondary battery pack capable of reducing power consumption when not in use.

  A secondary battery such as a lithium ion battery uses a battery pack in which a protection circuit for preventing deterioration of battery performance and ensuring safety is integrated. Normally, this protection circuit is configured to operate by receiving power supply internally from the secondary battery body. FIG. 3 is a diagram showing an example of a circuit configuration of a conventional secondary battery pack, where 1 is a secondary battery, 5 is a secondary battery block in which they are connected in multiple stages, and 2 is a protection circuit. The protection circuit 2 detects at least one abnormality among overcharge, overdischarge, overcurrent, and overheat of the secondary battery pack, and adjusts the charge voltage of each secondary battery and the secondary battery based on the detection result. It has a protection function for controlling block charging and discharging circuit shut-off and connection.

  As described above, even when the conventional secondary battery pack is not connected to the external load circuit, the protection circuit is always in an operating state. Patent Document 1 shows a case where a control circuit for monitoring and displaying the battery remaining amount together with the protection circuit is installed in the secondary battery pack, and when the secondary battery is not attached, Means for reducing the power consumption by stopping the power supply to the control circuit is shown. Patent Document 2 discloses a secondary battery pack having a built-in semiconductor power consuming circuit that realizes a circuit for calculating the remaining capacity of the secondary battery together with a protection circuit. The above-described semiconductor power consuming circuit includes a secondary battery pack. A method of reducing power consumption when not in use by adopting a configuration in which power is supplied via an external device connected to is shown.

JP 2001-155781 A JP 2002-324588 A

  In a secondary battery pack, minimizing the power consumption during periods when it is not being used, that is, during storage, such as before shipment, is to allow the secondary battery itself to have an acceptable storage period and the electrical equipment in which it is installed. This is very important for extending the storage period. For this purpose, as described above, Patent Document 1 discloses means for reducing power consumption by stopping power supply to the control circuit when the secondary battery is not attached. Document 2 also shows means for not supplying power to the semiconductor power consumption circuit when not in use.

  However, the power of the protection circuit is also a consumption that cannot be ignored in the long term. In general, the protection circuit is integrated into an IC for obtaining low power consumption and reducing the price, and its operation mode is automatically switched between the low consumption mode and the normal mode based on the charge amount of the secondary battery. For example, if the shipping charge amount of the secondary battery pack is about 30 to 50%, the operation mode of the protection circuit becomes the normal mode, and a consumption current of several tens to several hundreds μA is generated. Become. Even in the secondary battery packs of Patent Documents 1 and 2 described above, if a means for reducing the power consumption of the protection circuit itself is not provided, the allowable storage period is not sufficient and is limited by the self-consumption current.

  Therefore, an object of the present invention is to provide a secondary battery pack that can reduce the self-consumption current of the protection circuit when the secondary battery pack is not used and extend the allowable storage period.

  In order to solve the above problems, a secondary battery pack according to the present invention includes a secondary battery block including one to a plurality of secondary batteries, and at least one of overcharge, overdischarge, overcurrent, and overheat of the secondary battery block. In a secondary battery pack having a protection circuit that performs protection by detecting one or more abnormalities, the power supply line is cut off or connected to at least one of the power supply lines connecting the protection circuit and the secondary battery block. A forced cutoff circuit is inserted.

  It is also possible to have a trigger circuit connected to an external connection terminal of the secondary battery pack, and to shut off and control connection of the forced cutoff circuit by an electric signal generated by the trigger circuit.

  The forced cutoff circuit or the trigger circuit may have an input terminal, and the forced cutoff circuit may be in a cutoff state by applying a specified voltage to the input terminal.

  The forced cutoff circuit or the trigger circuit may have at least two input terminals, and the forced cutoff circuit may be in a cutoff state by short-circuiting the two input terminals.

  The forced cut-off circuit or the trigger circuit has an input portion configured such that two electrode terminals are brought into contact with each other by elastic force, and an insulator is inserted between the two electrode terminals to be in an open state. The forced cutoff circuit can be configured to be in a cutoff state, and further, the insulator inserted between the two electrode terminals is pulled out, and the two electrode terminals are returned to a short-circuited state, thereby The interruption circuit may be connected.

  Moreover, you may set so that the said forced cutoff circuit will be in a connection state by charging a secondary battery pack.

  As described above, the present invention enables a significant reduction in current consumption during a non-use period of the secondary battery pack by cutting off the power supply from the secondary battery to the protection circuit. According to the present invention, it is possible to obtain a secondary battery pack capable of reducing the self-consumption current of the protection circuit when the secondary battery pack is not used and extending the allowable storage period.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a circuit configuration diagram showing a first embodiment of a secondary battery pack according to the present invention. In FIG. 1, protection is performed by detecting at least one abnormality among a secondary battery block 5 composed of a plurality of secondary batteries 1 and overcharge, overdischarge, overcurrent, and overheat of the secondary battery block 5. In the secondary battery pack having the protection circuit 2, a forced cutoff circuit 3 for cutting or connecting the power supply line is inserted into one of the power supply lines connecting the protection circuit 2 and the secondary battery block 5.

  In addition, the trigger circuit 4 is connected to the external connection terminal 6 of the secondary battery pack, and the forcible cutoff circuit 3 is cut off and connected by an electric signal generated by the trigger circuit 4. The trigger circuit 4 has a function of generating an electrical signal for controlling the cutoff and connection of the forced cutoff circuit 3 based on input information.

  Here, the forced cutoff circuit 3 is a circuit having a switching function for turning on and off a current of about several tens to several hundreds μA supplied to the protection circuit 2, and can be configured by a normal FET element or the like. The trigger circuit 4 is also a general circuit that generates a signal for turning on and off the FET element based on input information such as an input voltage and an input resistance value.

  Next, the interruption / connection operation of the protection circuit 2 of the secondary battery pack according to the present embodiment will be described. In the secondary battery pack shown in FIG. 1, first, a prescribed potential state is applied to the input part of the trigger circuit 4 of the secondary battery pack that has undergone the prescribed treatment and can be shipped. The trigger circuit 4 outputs a cutoff signal to the forced cutoff circuit 3 when a specified potential state is input. When the cutoff signal is input, the forced cutoff circuit 3 cuts off the power supply line to the protection circuit 2, and the protection circuit 2 enters a low current consumption state. In this state, the secondary battery pack is shipped.

  When used after shipment, when the secondary battery pack is charged, the trigger circuit 4 detects the charge and outputs a return signal to the forced cutoff circuit 3. When the return signal is input, the forced cutoff circuit 3 connects the power supply line to the protection circuit 2, and the secondary battery pack enters the normal operation mode.

  FIG. 2 is a circuit configuration diagram of the second embodiment of the secondary battery pack according to the present invention. In FIG. 2, as in FIG. 1, a secondary battery block 5 composed of a plurality of secondary batteries 1 and at least one abnormality detection among overcharge, overdischarge, overcurrent, and heating of the secondary battery block 5 is detected. In the secondary battery pack having the protection circuit 2 that performs protection, the forced cutoff circuit 3 that shuts off or connects the power supply line is inserted into one of the power supply lines that connect the protection circuit 2 and the secondary battery block 5. ing.

  In addition, the trigger circuit 4 is connected to the external connection terminal 6 of the secondary battery pack, and the forcible cutoff circuit 3 is cut off and connected by an electric signal generated by the trigger circuit 4. In the present embodiment, the trigger circuit 4 has an input portion 7 configured such that the two electrode terminals are brought into contact with each other by elastic force, and the insulator 10 is inserted between the two electrode terminals to open the trigger circuit 4. As a result, the forced cutoff circuit 3 enters a cutoff state, and the forced cutoff circuit 3 is connected by pulling out the insulator 10 inserted between the two electrode terminals and returning the two electrode terminals to a short-circuit state. It is set to become. That is, the trigger circuit 4 is configured by a mechanical switch whose input unit 7 is normally short-circuited, and has a function of controlling the shut-off and return of the forced shut-off circuit 3 based on open / short information depending on whether or not the insulator 10 is inserted. It is.

  Next, the interruption / connection operation of the protection circuit 2 of the secondary battery pack of the present embodiment will be described. In the secondary battery pack shown in FIG. 2, first, the insulator 10 is inserted into the input part 7 of the trigger circuit 4 of the secondary battery pack that has been subjected to the prescribed treatment and can be shipped, and is opened. The trigger circuit 4 outputs a cutoff signal to the forced cutoff circuit 3 when the open state is input. When the cutoff signal is input, the forced cutoff circuit 3 cuts off the power supply line to the protection circuit 2, and the protection circuit 2 enters a low current consumption state. In this state, the secondary battery pack is shipped.

  When used after shipment, when the insulator 10 inserted in the input part 7 of the trigger circuit 4 of the secondary battery pack is pulled out and the input part 7 is returned to the normal short circuit state, the trigger circuit 4 detects the input part short circuit. Then, a return signal is output to the forced cutoff circuit 3. When the return signal is input, the forced cutoff circuit 3 connects the power supply line to the protection circuit 2, and the secondary battery pack enters the normal operation mode.

  In the above embodiment, the case where the forcible cutoff circuit is in the cutoff state when the two electrode terminals are open has been shown. However, the two terminals are set to be in the cutoff state when the two electrode terminals are short-circuited. It is also possible to install a device that short-circuits between the two electrode terminals at the time of shipment, and to remove the short-circuited device during use.

  As described above, in the secondary battery pack according to the present invention, the protection circuit 2, the forced cutoff circuit 3, and the trigger circuit 4 shut off the power supply line of the protection circuit 2 at the time of shipment of the secondary battery pack and charge it when used. Until the recovery operation such as the above is performed, the secondary battery pack can be configured such that the consumption current of the protection circuit that occupies most of the circuit consumption can be reduced and the allowable storage period of the secondary battery pack can be extended.

  In the above embodiment of the secondary battery pack according to the present invention, the example in which the potential level and the contact state of the mechanical switch are used as the input information of the trigger circuit 4 has been described. However, light, magnetism, temperature, humidity, vibration Control is performed by generating an electrical signal using a phenomenon that causes a voltage, current generation, or a change in electrical resistance value due to current, gas, etc., and using that as input information to generate a cutoff / reset signal for the forced cutoff circuit 3 May be performed.

  The trigger circuit 4 can be omitted by configuring the trigger circuit 4 as a part of the forced cutoff circuit 3 or by providing the forced cutoff circuit 3 with the function of the trigger circuit 4.

The circuit block diagram which shows 1st embodiment of the secondary battery pack which concerns on this invention. The circuit block diagram which shows 2nd embodiment of the secondary battery pack which concerns on this invention. The figure which shows an example of the circuit structure of the conventional secondary battery pack.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Secondary battery 2 Protection circuit 3 Forced cutoff circuit 4 Trigger circuit 5 Secondary battery block 6 External connection terminal 7 Input part 10 Insulator

Claims (3)

A secondary battery block composed of 1及至plurality of secondary batteries, overcharge of the secondary battery block, overdischarge, overcurrent, and a protection circuit for protecting performing at least one abnormality detection of overheating a, a rechargeable battery pack has been inserted a forced interruption circuit for interrupting or connecting a power supply line to the power line connecting the battery block and the protection circuit,
A trigger circuit connected to an external connection terminal of the secondary battery pack;
The trigger circuit includes an input unit including at least two electrode terminals, and outputs a cut-off signal or a return signal to the forced cut-off circuit according to a short-circuit state of the electrode terminals,
The secondary battery pack, wherein the forced cutoff circuit performs cutoff and connection control of the power supply line in accordance with the cutoff signal and the return signal . By between before Symbol trigger circuit two electrode terminals has an input configured to be in contact with each other by the elastic force, to open and insert an insulator between the two electrode terminals, the forced blocking rechargeable battery pack of claim 1, wherein the circuit are cut off. 3. The secondary circuit according to claim 2 , wherein the forcible cutoff circuit is connected by pulling out an insulator inserted between the two electrode terminals and returning the two electrode terminals to a short-circuited state. Battery pack.

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