WO2015037210A1

WO2015037210A1 - Switching circuit

Info

Publication number: WO2015037210A1
Application number: PCT/JP2014/004503
Authority: WO
Inventors: 吉弘米田
Original assignee: デクセリアルズ株式会社
Priority date: 2013-09-11
Filing date: 2014-09-02
Publication date: 2015-03-19
Also published as: TWI653654B; JP2015056960A; CN105531895A; KR20160055148A; TW201517107A; CN105531895B; JP6196856B2; KR102180652B1

Abstract

The present invention disconnects a shorted current path and shorts an open current path in a prescribed order and irreversibly switches a current path. A switch element (26) for energizing a second heating element (11) is connected to the second heating element (11). An open terminal of a first heating element (2) is connected to a connecting terminal (16) for the second heating element (11) and an open-side soluble conductor (12). As a result of the operation of the switch element (26), the second heating element (11) is energized and generates heat, the open-side soluble conductor (12) fuses, and a main circuit (25) and second circuit (24) are disconnected. As a result of the the fusing of the open-side soluble conductor (12), the first heating element (2) is energized and generates heat, a short-side soluble conductor (3) fuses, a switch (4) is shorted, and current flows between the main circuit (25) and a first circuit (23).

Description

Switching circuit

Cross-reference to related applications

This application claims the priority of Japanese Patent Application No. 2013-188804 (filed on September 11, 2013), the entire disclosure of which is incorporated herein by reference.

The present invention relates to a switching circuit that switches current paths.

Many of secondary batteries that can be charged and repeatedly used are processed into a battery pack and provided to the user. In particular, in lithium ion secondary batteries with high weight energy density, in order to ensure the safety of users and electronic devices, a number of protection circuits such as overcharge protection and overdischarge protection are generally incorporated in the battery pack, It has a function to shut off the output of the battery pack in a predetermined case.

Among such protection elements, there is one that performs overcharge protection or overdischarge protection operation of the battery pack by turning on / off the output using an FET switch built in the battery pack. However, if the FET switch is short-circuit-broken for some reason, a lightning surge or the like is applied and a momentary large current flows, or the life of the battery cell abnormally decreases the output voltage, or conversely, an excessive abnormality Even when a voltage is output, the battery pack or the electronic device must be protected from an accident such as ignition. Therefore, in order to safely shut off the output of the battery cell under any such conceivable abnormal condition, a protection element consisting of a fuse element having a function of interrupting the current path by an external signal is used. .

As described in Patent Document 1, as a protection element of a protection circuit for a lithium ion secondary battery or the like, it is possible to extend across the first electrode, the heating element lead electrode, and the second electrode on the current path. In some cases, a molten conductor is connected to be a part of a current path, and the soluble conductor on this current path is fused and cut by self-heating due to an overcurrent or a heating element provided inside a protective element. In such a protective element, the current path is interrupted by collecting the molten liquid soluble conductor on the conductor layer connected to the heating element.

JP, 2010-003665, A JP 2004-185960 A JP 2012-003878 A

However, even if the charge / discharge current circuit of the abnormal lithium ion secondary battery is shut off, a large amount of energy corresponding to the battery capacity is still stored in the battery cell, and an abnormality occurs in the protection circuit, etc. Risks such as heat generation accident due to leakage current from the battery cell are assumed. Therefore, after stopping use of the battery pack, it is preferable to discharge the internal battery cells until the voltage drops to a safe voltage.

Thus, for example, in a battery pack of a lithium ion secondary battery, an element is required which reliably switches the current path of the battery cell from the charge / discharge path in the normal state to the discharge path in the abnormal state.

Therefore, an object of the present invention is to provide a switching circuit that switches a current path irreversibly by performing shutoff of a current path that is short-circuited in a normal state and shorting of a current path used in an abnormal state in a predetermined order. I assume.

In order to solve the problems described above, the switching circuit according to the present invention is connected to the first heating element that generates heat when current flows, one end connected to the first heating element, and the other end connected to the main circuit And a switch connected to the main circuit at one end and to the first circuit at the other end, and connected at one end to the first circuit. The short-circuited soluble conductor is fused by the heat generated by the body, and the switch is short-circuited by the molten conductor, a second heating element generating heat when current flows, and the second heating element The open-side soluble conductor includes an open-side soluble conductor connected at one end and connected to the second circuit at the other end and connected to the main circuit at the other end, and the heat generated by the second heating element generates heat. Open circuit to melt the At one end of the second heating element, a switch element for receiving current from the main circuit is connected to the second heating element in response to the switching signal, and the open end of the first heating element of the short circuit The second heating element of the open circuit is connected to the connection end of the open-side soluble conductor, and the switch element is operated, whereby the second heating element of the open circuit is energized and generates heat. And the main circuit and the second circuit are cut off, and the first heating element of the short circuit is energized and generates heat due to the melting of the open side soluble conductor. The short circuit side soluble conductor melts, the switch is short circuited, and the main circuit and the first circuit are energized.

In the switching circuit according to the present invention, the first heating element that generates heat when a current flows, and the short-circuit side soluble conductor having one end connected to the first heating element and the other end connected to the main circuit And a switch having one end connected to the short circuit side soluble conductor and the other connected to the main circuit, and the other end connected to the first circuit, the heat generated by the first heating element generating heat A short circuit which melts the short circuit side soluble conductor and shorts the switch by the molten conductor, a second heating element which generates heat when current flows, and the second heating element are connected with one end being the first An open circuit comprising an open-side soluble conductor connected to the second circuit and having the other end connected to the main circuit, wherein the heat generated by the second heat generating member melts the open-side soluble conductor At one end of the first heating element A first switch element for receiving current from the main circuit is connected to the first heat generating body in response to the switching signal, and a switching signal is received at one end of the second heat generating body to generate the second heat generation. A second switch element for conducting current from the main circuit is connected to the body, and the second heating element of the open circuit is energized and generates heat when the second switch element is operated. The soluble conductor is melted off, the main circuit and the second circuit are disconnected, and the first switch element operates to cause the first heating element of the short circuit to conduct electricity and generate heat. The short circuit side soluble conductor melts, the switch is short circuited, and the main circuit and the first circuit are energized.

Further, in the switching circuit according to the present invention, the first heating element that generates heat when a current flows and the short-circuit side whose one end is connected to the first heating element and the other end is connected to the first circuit A heat conductor, and a switch having one end connected to the short circuit side soluble conductor and the switch connected to the first circuit and the other end connected to the main circuit, the heat generated by the first heating element Is connected to the second heating element that generates heat when current flows, and the short-circuited portion that melts the short-circuit side soluble conductor and short-circuits the switch by the molten conductor, and is connected to the second heating element Is connected to the other end of the switch and the main circuit, and the other end is connected to the second circuit, and the open side soluble is generated by the heat generated by the second heating element. And an open portion for melting the conductor; The heating element is connected to a first switch element for receiving current from the main circuit in response to the switching signal to cause the first heating element to conduct current, and the second heating element receives the switching signal to receive the second signal. The heating element is connected to a second switch element for supplying a current from the main circuit, and the second switching element operates to cause the second heating element in the open portion to conduct electricity, generate heat, and open the opening. The side soluble conductor is melted off, the main circuit and the second circuit are disconnected, and the first switch element operates to cause the first heating element of the short circuit portion to conduct electricity and generate heat. The short circuit side soluble conductor melts, the switch is short circuited, and the main circuit and the first circuit are energized.

According to the present invention, by operating the switch element, the current path from the main circuit to the second circuit is cut off and a current path to the first circuit is constructed, and the current path of the main circuit is set to the second The circuit can be switched to the first circuit. At this time, according to the present invention, interruption and short circuit of the current path can be performed irreversibly by melting the first, open-side soluble conductor.

FIG. 1 is a circuit diagram of a short circuit constituting a switching circuit, in which (A) shows before a short circuit and (B) shows after a short circuit. FIG. 2 is a circuit diagram of an open circuit constituting the switching circuit, in which (A) shows the state before opening and (B) shows the state after opening. FIG. 3 is a block diagram showing the configuration of the first switching circuit. FIG. 4 is a circuit diagram showing a first switching circuit before switching, in which (A) is an example provided with two open-side soluble conductors, (B) an example provided with one open-side soluble conductor Indicates FIG. 5 is a circuit diagram showing a first switching circuit in which the second heating element is energized by the switch element. FIG. 6 is a circuit diagram showing a first switching circuit in which the first heating element is energized. FIG. 7 is a circuit diagram showing a first switching circuit after switching. FIG. 8 is a circuit diagram of a battery pack to which the first switching circuit is applied. FIG. 9 is a circuit diagram showing a modification of the first switching circuit. FIG. 10 is a circuit diagram of a battery pack to which a first switching circuit according to a modification is applied. FIG. 11 is a block diagram showing the configuration of the second switching circuit. FIG. 12 is a circuit diagram showing a second switching circuit, wherein (A) shows an example provided with two open-side soluble conductors, and (B) shows an example provided with one open-side soluble conductor. FIG. 13 is a circuit diagram of a battery pack to which the second switching circuit is applied. FIG. 14 is a circuit diagram showing a modification of the second switching circuit. FIG. 15 is a circuit diagram of a battery pack to which a second switching circuit according to a modification is applied. FIG. 16 is a circuit diagram showing a third switching circuit, in which (A) shows an example having two open-side soluble conductors, and (B) shows an example having one open-side soluble conductor. FIG. 17 is a circuit diagram of a battery pack to which the third switching circuit is applied. FIG. 18 is a circuit diagram showing a modification of the third switching circuit. FIG. 19 is a circuit diagram of a battery pack to which a third switching circuit according to a modification is applied.

Hereinafter, the switching circuit to which the present invention is applied will be described in detail with reference to the drawings. The present invention is not limited to the following embodiments, and it goes without saying that various modifications can be made without departing from the scope of the present invention. Further, the drawings are schematic, and the ratio of each dimension may be different from the actual one. Specific dimensions and the like should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios among the drawings are included.

The switching circuit to which the present invention is applied is a short circuit or a short circuit part connected between electrodes mutually opened through the melting conductor by melting the fusible conductor, and a short circuit through the fusible conductor Between the electrodes being made has an open circuit or opening that is interrupted by melting the fusible conductor. First, the operation principle of the short circuit and the open circuit will be described.

As shown in FIG. 1A, the short circuit 1 is connected in series to the first heating element 2 and the first heating element 2, and the short circuit side melts due to the heat generation of the first heating element 2. A conductor 3 is provided with first and

second electrodes

5 and 6 which constitute a switch 4 which is open to each other and which is short-circuited through the molten conductor by melting the short-circuit side soluble conductor 3. The first electrode 5 is connected to a power supply (not shown), and the second electrode 6 is connected to an external circuit to be connected when the switch 4 is turned on. Further, the first heat generating body 2 is connected to a switch element such as a FET (not shown) via the first heat generating body electrode 7 so that energization is controlled.

As shown in FIG. 1B, when the switch element is operated, the short circuit 1 is supplied with power to the first heating element 2 through the first electrode 5 and the short circuit soluble conductor 3. Due to the heat generation of the first heating element 2, the short circuit side soluble conductor 3 is fused and cut. Then, in the short circuit 1, the molten conductor of the short circuit side soluble conductor 3 agglomerates between the first and

second electrodes

5 and 6, thereby shorting the first and

second electrodes

5 and 6. As a result, in the short circuit 1, the switch 4 is turned on to energize the power supply and the external circuit.

As shown in FIG. 2A, the open circuit 10 includes the second heat generating body 11, the open side soluble conductor 12 which is melted and cut by the heat generation of the second heat generating body 11, and the open side soluble conductor 12 And third and

fourth electrodes

13 and 14 connected to each other. The third and

fourth electrodes

13 and 14 are provided on the current path, and the second heat generating body 11 is connected to a switch element such as an FET (not shown) via the second heat generating electrode 15 to energize it. Is controlled.

In the open circuit 10, as shown in FIG. 2 (B), when the switch element is operated, power is supplied to the second heat generating body 11 through the third electrode 13 and the open side soluble conductor 12; Due to the heat generation of the second heat generating body 11, the open side soluble conductor 12 is melted down. Thereby, the open circuit 10 can cut off the current path.

[First switching circuit]
As shown in FIG. 3, the first switching circuit 30 constitutes the short circuit 1 and is opened with the short circuit element 21 connected to the power supply circuit 25 serving as the main circuit and the first external circuit 23 to be energized after switching. The circuit 10 is configured, and includes a power supply circuit 25 and an open element 22 connected to a second external circuit 24 to be energized before switching. The first switching circuit 30 is supplied with power to the second heating element 11 by the switch element 26 that has received the switching signal. Thereby, the second heat generating body 11 generates heat, and after the third and

fourth electrodes

13 and 14 are shut off, the first heat generating body 2 generates heat, and the first and

second electrodes

5 and 6 are generated. There is a short circuit between them. Thus, the first switching circuit 30 can switch the current path of the power supply circuit 25 from the second external circuit 24 to the first external circuit 23.

Specifically, the first switching circuit 30 has a circuit configuration shown in FIG. The short circuit 1 includes a first heating element 2 that generates heat when a current flows, and a short circuit soluble conductor 3 having one end connected to the first heating element 2 and the other end connected to a power supply circuit 25; The switch 4 includes one end connected to the short circuit side soluble conductor 3 and the power supply circuit 25 and the other end connected to the first external circuit 23.

The switch 4 is connected to the power supply circuit 25 through the first electrode 5 and to the first external circuit 23 through the second electrode 6. Further, the first heat generating body 2 is connected to the connection end electrode 16 of the open circuit 10 via the first heat generating body electrode 7.

In addition, the open circuit 10 is connected to the second heating element 11 that generates heat when a current flows, and the second heating element 11, and one end is connected to the power supply circuit 25, and the other end is the second external circuit. And an open-side fusible conductor 12 connected to the T.24. In the first switching circuit 30 shown in FIG. 4A, the open side soluble conductor 12 has one end connected to the power supply circuit 25 through the third electrode 13 and the other end connected to the second heating element 11 A first open-ended soluble conductor 12 a, and one end connected to the second external circuit 24 via the fourth electrode 14 and the other end connected to the second heating element 11. And an open side soluble conductor 12b.

In addition, you may comprise the open circuit 10 only by the 1st open | release side soluble conductor 12a, as shown to FIG. 4 (B). In this case, one end of the first open-side soluble conductor 12 a is connected to the power supply circuit 25 through the third electrode 13, and the other end is connected through the second heating element 11 and the fourth electrode 14. It is connected to the second external circuit 24.

In addition, the first switching circuit 30 receives the switching signal at one end of the second heat generating body 11 via the second heat generating body electrode 15 and supplies a current from the power supply circuit 25 to the second heat generating body 11. A switch element 26 to be energized is connected. In the first switching circuit 30, the first heating element electrode 7 of the short circuit 1 and the connection end electrode 16 to which the second heating element 11 of the open circuit 10 and the open side soluble conductor 12 are connected are included. It is connected.

Switch element 26 is formed of, for example, a field effect transistor (FET), and controls conduction and interruption of the current path to second heating element 11 by controlling the gate voltage.

[Operation of first switching circuit]
In the initial state, the first switching circuit 30 having such a configuration forms a current path from the power supply circuit 25 to the second external circuit 24 via the open circuit 10, as shown in FIG. At this time, in the first switching circuit 30, power supply to the second heat generating body 11 is restricted by the switch element 26, and both ends of the first heat generating body 2 have substantially the same potential. Hardly flows.

When it becomes necessary to switch the current path of the power supply circuit 25 from the second external circuit 24 to the first external circuit 23, a switching signal is output to the switch element 26. When the switch element 26 receives the switching signal, it controls the current so as to supply power to the second heating element 11. Thereby, in the first switching circuit 30, as shown in FIG. 5, the second heating element 11 of the open circuit 10 is energized and generates heat, and the open-side soluble conductor 12 is melted and disconnected. Therefore, the current path from the power supply circuit 25 to the second external circuit 24 is cut off.

Then, as shown in FIG. 6, the current from the power supply circuit 25 flows into the short circuit 1 through the first electrode 5, and the short-side soluble conductor 3, the first heating element 2, and the first It flows to the open circuit 10 and the switch element 26 side through the heating element electrode 7. As a result, in the first switching circuit 30, the first heating element 2 of the short circuit 1 is energized and generates heat, and as shown in FIG. A short circuit occurs between the first and

second electrodes

5 and 6, that is, the switch 4 is turned on, and a current path from the power supply circuit 25 to the first external circuit 23 is established.

In addition, since the electric power feeding path is interrupted | blocked by melting and cutting both the open side soluble conductor 12 and the short circuit side soluble conductor 3, the 2nd heat generating body 11 stops heat generation. In addition, since the feeding path is cut off by melting the short-circuit side soluble conductor 3 in the first heating element 2, the heat generation is stopped.

Thus, according to the first switching circuit 30, by operating the switch element 26, the current path to the second external circuit 24 through the third and

fourth electrodes

13 and 14 is interrupted. A current path from the power supply circuit 25 to the first external circuit 23 through the first electrode 5, the switch 4 and the second electrode 6 is constructed, and the current path of the power supply circuit 25 is It is possible to switch to the one external circuit 23.

Further, according to the first switching circuit 30, the open side soluble conductor 12 is a short circuit between the third and

fourth electrodes

13 and 14 and the short circuit between the first and

second electrodes

5 and 6 Irreversible by melting the side soluble conductor 3. Therefore, as compared with the case of electronically switching by software or the like, it is possible to improve the switching failure due to a malfunction and to improve the vulnerability to illegal switching due to cracking or the like.

[Implementation example of first switching circuit]
Such a first switching circuit 30 is used by being incorporated into a circuit in a battery pack 40 of a lithium ion secondary battery, for example, as shown in FIG. The battery pack 40 has, for example, a battery stack 45 consisting of battery cells 41 to 44 of a total of four lithium ion secondary batteries.

The battery pack 40 includes a battery stack 45, a charge / discharge control circuit 50 for controlling charge / discharge of the battery stack 45, and the present invention for interrupting charging when the battery stack 45 is abnormal and for radiating the electric energy in the battery stack 45. First switching according to the detection result of the short circuit 21 and open circuit 22 constituting the first switching circuit 30 applied, the detection circuit 46 detecting the voltage of each of the battery cells 41 to 44, and the detection circuit 46 And a switch element 26 for controlling the operation of the circuit 30.

The battery stack 45 is a series connection of battery cells 41 to 44 requiring control for protection from an overcharge and an overdischarge state, and is detachable via the positive electrode terminal 40 a and the negative electrode terminal 40 b of the battery pack 40. The charging circuit 55 is connected to the charging circuit 55, and the charging voltage from the charging circuit 55 is applied. The battery pack 40 charged by the charging circuit 55 can operate the electronic device by connecting the positive electrode terminal 40 a and the negative electrode terminal 40 b to the electronic device operated by the battery.

The charge and discharge control circuit 50 controls the operation of the two

current control elements

51 and 52 connected in series in the current path flowing from the battery stack 45 to the charge circuit 55.

Current control elements

51 and 52 are formed of, for example, a field effect transistor (hereinafter referred to as FET), and control of the gate voltage by charge / discharge control circuit 50 allows conduction and interruption of the current path of battery stack 45. Control. The charge / discharge control circuit 50 operates by receiving power supply from the charge circuit 55, and cuts off the current path when the battery stack 45 is overdischarged or overcharged according to the detection result by the detection circuit 46, The operation of the

current control elements

51 and 52 is controlled.

The short circuiting element 21 is connected in parallel to the battery stack 45 and is connected in series to the protective resistor 31 for discharging the electric energy stored in the battery stack 45 with the upper limit discharge current of the battery cells 41 to 44 or less. There is. Thus, the first switching circuit 30 constitutes a discharge circuit 32 provided with the short circuiting element 21 and the protective resistor 31.

The open element 22 is connected on the charge / discharge current circuit 33 between the battery stack 45 and the charge circuit 55, and the operation is controlled by the switch element 26.

The detection circuit 46 is connected to each of the battery cells 41 to 44, detects the voltage value of each of the battery cells 41 to 44, and supplies each voltage value to the charge and discharge control circuit 50. Further, the detection circuit 46 outputs a control signal for controlling the switch element 26 when any one of the battery cells 41 to 44 becomes the overcharge voltage.

Switch element 26 is formed of, for example, an FET, and when the voltage value of battery cells 41 to 44 becomes a voltage exceeding a predetermined overcharge state by a detection signal output from detection circuit 46, first switching circuit 30. To shut off the charge / discharge current circuit 33 of the battery stack 45 regardless of the switch operation of the

current control elements

51 and 52, and the current path of the battery stack 45 through the open / close element 22. Then, control is made to switch to the discharge circuit 32 via the shorting element 21.

Specifically, when the detection circuit 46 detects an abnormal voltage in any of the battery cells 41 to 44, the battery pack 40 outputs a switching signal to the switch element 26. The switch element 26 controls the current of the battery stack 45 so as to energize the second heating element 11 of the open element 22. Thereby, the first switching circuit 30 melts the open-side soluble conductor 12 and cuts off the charge / discharge current circuit 33 of the battery stack 45. Furthermore, in the first switching circuit 30, the first heating element 2 is energized and the short-circuit side soluble conductor 2 is fused, whereby the first and

second electrodes

5, 6 are short-circuited. The current path is switched to the discharge circuit 32 side provided with the protective resistor 31.

Thus, the battery pack 40 in which the first switching circuit 30 is incorporated cuts off the charge / discharge current circuit 33 of the battery stack 45 which has caused an abnormality, and a battery stack in which a large electric energy corresponding to the battery capacity is stored. The 45 current paths are switched to the discharge circuit 32 provided with the protective resistor 31. Therefore, the battery pack 40 can be discharged until the internal battery cells 41 to 44 drop to a safe voltage after stopping use.

[Built-in protection element]
In the first switching circuit 30, as shown in FIG. 8, in addition to providing the protective resistor 31 on the discharge circuit 32, the protective resistor 31 may be incorporated in the short circuit 1 as shown in FIG. In this case, as shown in FIG. 10, the discharge circuit 32 of the battery pack 40 does not need to have the protective resistor 31.

[Second switching circuit]
Next, the second switching circuit 60 will be described. In the following description, the same components as those of the first switching circuit 30 described above are denoted by the same reference numerals, and the details thereof are omitted. As shown in FIG. 11, the second switching circuit 60 constitutes the short circuit 1, and constitutes the open circuit 10 and the short circuit element 21 connected to the power supply circuit 25 and the first external circuit 23 to be energized after switching. And an open element 22 connected to a power supply circuit 25 and a second external circuit 24 which is energized before switching.

In the second switching circuit 60, the short circuit element 21 is connected to the first switch element 61, and the open element 22 is connected to the second switch element 62. The short circuiting element 21 is supplied with power to the first heating element 2 by the first switch element 61 which has received the switching signal. Further, the open element 22 is supplied with power to the second heating element 11 by the second switch element 62 that has received the switching signal. Therefore, according to the second switching circuit 60, the order of the short circuit by the short circuit element 21 and the opening by the open element 22 is changed according to the output sequence of the switching signals to the first and

second switch elements

61 and 62. Can.

Specifically, the second switching circuit 60 has a circuit configuration shown in FIG. The short circuit 1 includes a first heating element 2, a short circuit soluble conductor 3 and a switch 4, and the heat generated by the first heating element 2 causes the short circuit soluble conductor 3 to melt and cut. Short-circuits the switch 4. In the second switching circuit 60, the short circuit 1 includes the first switching circuit 30 except that the first heating element 2 is connected to the first switch element 61 via the first heating element electrode 7. The same configuration as

In addition, the open circuit 10 includes the second heat generating body 11 and the open side soluble conductor 12, and the heat generated by the second heat generating body 11 causes the open side soluble conductor 12 to melt and cut. In the second switching circuit 60, the open circuit 10 is a first switching circuit except that the second heating element 11 is connected to the second switch element 62 via the second heating element electrode 15. It has the same configuration as 30.

In the second switching circuit 60 shown in FIG. 12A, one end of the open-side soluble conductor 12 is connected to the power supply circuit 25 through the third electrode 13 and the other end is the second heating element 11. A first open-ended soluble conductor 12a connected to the second external circuit 24 via the fourth electrode 14 at one end and a second heating element 11 at the other end And two open side soluble conductors 12b.

Further, also in the switching circuit 60, as shown in FIG. 12B, the open circuit 10 may be configured by only the first open-side soluble conductor 12a. In this case, one end of the first open side soluble conductor 12 a is connected to the power supply circuit 25 via the third electrode 13, and the other end is connected via the second heating element 11 and the fourth electrode 14 to the first open side soluble conductor 12 a. It is connected to the two external circuits 24.

[Operation of second switching circuit]
In the initial state, the second switching circuit 60 having such a configuration configures a current path from the power supply circuit 25 to the second external circuit 24 via the open circuit 10, as shown in FIG. At this time, in the short circuit 1, the power supply to the first heating element 2 is restricted by the first switch element 61, and the switch 4 is turned off. Further, in the open circuit 10, the power supply to the second heating element 11 is restricted by the second switch element 62.

When it becomes necessary to switch the current path of the power supply circuit 25 from the second external circuit 24 to the first external circuit 23, first, a switching signal is output to the second switch element 62. When the second switch element 62 receives the switching signal, it controls the current to supply power to the second heating element 11. As a result, in the second switching circuit 60, the second heating element 11 of the open circuit 10 is energized and generates heat, and the open-side soluble conductor 12 is fused. Therefore, the current path from the power supply circuit 25 to the second external circuit 24 is cut off.

Next, the second switching circuit 60 outputs a switching signal to the first switch element 61. When receiving the switching signal, the first switch element 61 controls the current so as to supply power to the first heating element 2. As a result, in the second switching circuit 60, the first heating element 2 of the short circuit 1 is energized and generates heat, and the short circuit side soluble conductor 3 is fused and disconnected, and the first and second electrodes 5 are made by this molten conductor. , 6 are shorted, that is, the switch 4 is turned on, and a current path from the power supply circuit 25 to the first external circuit 23 is established.

The second switching circuit 60 first outputs a switching signal to the first switch element 61 when the current path of the power supply circuit 25 needs to be switched from the second external circuit 24 to the first external circuit 23. After the current path from the power supply circuit 25 to the first external circuit 23 is constructed, a switching signal is output to the second switch element 62 to interrupt the current path leading to the second external circuit 24. It is also good. Thus, the current path can be switched from the second external circuit 24 to the first external circuit 23 without interruption of the power of the power supply circuit 25.

In addition, since the electric power feeding path is interrupted | blocked by the melting | disruption of the open side soluble conductor 12, the 2nd heat generating body 11 stops heat generation. In addition, since the feeding path is cut off by melting the short-circuit side soluble conductor 3 in the first heating element 2, the heat generation is stopped.

As described above, according to the second switching circuit 60, the first and

second switch elements

61 and 62 are operated to pass the third and

fourth electrodes

13 and 14 to the first external circuit 23. The current path from the power supply circuit 25 to the first external circuit 23 via the first electrode 5, the switch 4 and the second electrode 6 is constructed, and the current path of the power supply circuit 25 is The second external circuit 24 can be switched to the first external circuit 23.

At this time, also in the second switching circuit 60, the short circuit between the third and

fourth electrodes

13 and 14 and the short circuit between the first and

second electrodes

5 and 6 is released. Irreversible by melting the side soluble conductor 12. Therefore, as compared with the case of electronically switching by software or the like, it is possible to improve the switching failure due to a malfunction and to improve the vulnerability to illegal switching due to cracking or the like.

Further, according to the second switching circuit 60, the order of the short circuit by the short circuit element 21 and the opening by the open element 22 is changed according to the output sequence of the switching signals to the first and

second switch elements

61 and 62. Can.

[Implementation example of second switching circuit]
Such a second switching circuit 60 is incorporated in a circuit in a battery pack 40 of a lithium ion secondary battery, for example, as shown in FIG. In this case, the switching signal is sequentially output from the detection circuit 46 to the second switch element 62 and the first switch element 61, so that the charge / discharge current circuit 33 is first interrupted by the open element 22. Then, the discharge circuit 32 is shorted by the shorting element 21.

That is, when the detection circuit 46 detects an abnormal voltage in any of the battery cells 41 to 44, the battery pack 40 first outputs a switching signal to the second switch element 62. The second switch element 62 controls the current of the battery stack 45 so as to energize the second heating element 11 of the open element 22. Thereby, the second switching circuit 60 melts the open-side soluble conductor 12 and cuts off the charge / discharge current circuit 33 of the battery stack 45. When the interruption of the charge / discharge current circuit 33 is detected, then the detection circuit 46 outputs a switching signal to the first switch element 61. The first switch element 61 controls the current of the battery stack 45 such that the first heating element 2 of the short circuit element 21 is energized. As a result, the first heating element 2 is energized, and the short-circuit side soluble conductor 3 is fused, whereby the first and

second electrodes

5 and 6 are shorted, and the current path of the battery stack 45 is protected. It switches to the provided discharge circuit 32 side.

Thus, the battery pack 40 in which the second switching circuit 60 is incorporated cuts off the charge / discharge current circuit 33 of the battery stack 45 which has caused an abnormality, and a battery stack in which a large electric energy corresponding to the battery capacity is stored. The 45 current paths are switched to the discharge circuit 32 provided with a protective resistance. Therefore, the battery pack 40 can be discharged until the internal battery cells drop to a safe voltage after the use is stopped.

[Built-in protection element]
In the second switching circuit 60, as shown in FIG. 13, the protective resistance 31 may be provided on the discharge circuit 32. Alternatively, as shown in FIG. 14, the protective resistance 31 may be incorporated in the short circuit 1. . In this case, as shown in FIG. 15, the discharge circuit 32 of the battery pack 40 does not need to have the protective resistor 31.

[Third switching circuit]
Next, the third switching circuit 70 will be described. In the third switching circuit 70, as shown in FIG. 16, a short circuit portion 71 having the same function as the short circuit 1 described above and an open portion 72 having the same function as the open circuit 10 described above are integrally formed. There is.

The shorting portion 71 includes a first heating element 2 and a shorting-side soluble conductor 3 having one end connected to the first heating element 2 and the other end connected to the first external circuit 23 and one end on the shorting side The switch 4 is connected to the fusible conductor 3 and to the first external circuit 23, and the other end is connected to the power supply circuit 25.

The open portion 72 is connected to the second heat generating body 11 and the second heat generating body 11 and has one end connected to the other end of the switch 4 and the power supply circuit 25 and the other end connected to the second external circuit 24 And the open side soluble conductor 12.

In the short circuit portion 71, the first heat generating body 2 is connected to the first switch element 61 via the first heat generating body electrode 7. In the short circuit portion 71, the switch 4 is connected to the first external circuit 23 through the first electrode 5 and to the power supply circuit 25 through the second electrode 6. The second electrode 6 is also connected to one end side of the open side soluble conductor 12 provided in the open portion 72.

In the open portion 72, the second heat generating body 11 is connected to the second switch element 62 through the second heat generating body electrode 15. Further, in the open part 72, the open side soluble conductor 12 is connected to the second external circuit 24 through the fourth electrode 14, and connected to the power supply circuit 25 through the second electrode 6. In the third switching circuit 70 shown in FIG. 16 (A), the open side soluble conductor 12 has one end connected to the second external circuit 24 via the fourth electrode 14 and the other end a second heating element 11, a first open-side soluble conductor 12a connected to the second power supply circuit 25 via the second electrode 6 and a second heat-generating member 11 having the other end connected to the second heating element 11 And an open side soluble conductor 12b.

In addition, you may comprise the open part 72 only by the 1st open | release side soluble conductor 12a, as shown to FIG. 16 (B). In this case, one end of the first open side soluble conductor 12 a is connected to the power supply circuit 25 through the second electrode 6, and the other end is connected through the second heat generating body 11 and the fourth electrode 14. It is connected to the second external circuit 24.

[Operation of third switching circuit]
In the initial state, the third switching circuit 70 having such a configuration forms a current path from the power supply circuit 25 to the second external circuit 24 through the open portion 72, as shown in FIG. At this time, in the short circuit portion 71, power supply to the first heating element 2 is restricted by the first switch element 61, and the switch 4 is turned off. Further, in the open portion 72, power supply to the second heating element 11 is restricted by the second switch element 62.

When it becomes necessary to switch the current path of the power supply circuit 25 from the second external circuit 24 to the first external circuit 23, first, a switching signal is output to the second switch element 62. When the second switch element 62 receives the switching signal, it controls the current to supply power to the second heating element 11. As a result, in the third switching circuit 70, the second heating element 11 of the open portion 72 is energized and generates heat, and the open-side soluble conductor 12 is fused. Therefore, the current path from the power supply circuit 25 to the second external circuit 24 is cut off.

Next, the third switching circuit 70 outputs a switching signal to the first switch element 61. When receiving the switching signal, the first switch element 61 controls the current so as to supply power to the first heating element 2. Thereby, in the third switching circuit 70, the first heating element 2 of the short circuit portion 71 is energized and generates heat, and the short circuit side soluble conductor 3 is fused and cut, and the first and second electrodes 5 are made by the molten conductor. , 6 are shorted, that is, the switch 4 is turned on, and a current path from the power supply circuit 25 to the first external circuit 23 is established.

The third switching circuit 70 first outputs a switching signal to the first switch element 61 when the current path of the power supply circuit 25 needs to be switched from the second external circuit 24 to the first external circuit 23. After the current path from the power supply circuit 25 to the first external circuit 23 is constructed, a switching signal is output to the second switch element 62 to interrupt the current path leading to the second external circuit 24. It is also good. Thus, the current path can be switched from the second external circuit 24 to the first external circuit 23 without interruption of the power of the power supply circuit 25.

Thus, according to the third switching circuit 70, the first and

second switch elements

61 and 62 are operated to pass the second and

fourth electrodes

6 and 14 to the first external circuit 24. The current path from the power supply circuit 25 to the first external circuit 23 via the second electrode 6, the switch 4 and the first electrode 5 is constructed, and the current path of the power supply circuit 25 is The second external circuit 24 can be switched to the first external circuit 23.

At this time, also in the third switching circuit 70, the short circuit between the second and

fourth electrodes

6 and 14 and the short circuit between the first and

second electrodes

5 and 6 are opened. Irreversible by melting the side soluble conductor 12. Therefore, as compared with the case of electronically switching by software or the like, it is possible to improve the switching failure due to a malfunction and to improve the vulnerability to illegal switching due to cracking or the like.

Further, according to the third switching circuit 70, the order of the short circuit by the short circuit element 21 and the opening by the open element 22 is changed according to the output order of the switching signals to the first and

second switch elements

61 and 62. Can.

[Implementation example of the third switching circuit]
Such a third switching circuit 70 is incorporated in a circuit in a battery pack 40 of a lithium ion secondary battery, for example, as shown in FIG. In this case, the first switch element 61 connects between the first heat generating electrode 7 of the switching circuit 70 and the + side terminal of the battery stack 45. Further, the second switch element 62 connects between the second heating element electrode 15 of the switching circuit 70 and the negative side terminal of the battery stack 45. Further, in the switching circuit 70, the first electrode 5 connected to the negative side terminal of the battery stack 45 is at the negative potential, and the second electrode 6 connected to the positive side terminal of the battery stack 45 is at the positive potential The first heating element electrode 7 connected to the first switch element 61 is set to a positive potential. Further, in the switching circuit 70, the fourth electrode 14 connected to the charge / discharge current circuit 33 is set to the positive potential, and the second heating element electrode 15 connected to the second switch element 62 is set to the negative potential. .

In the battery pack 40, when a voltage abnormality is detected in any of the battery cells 41 to 44, a switching signal is sequentially output from the detection circuit 46 to the second switch element 62 and the first switch element 61. Thus, first, the charge / discharge current circuit 33 is interrupted by the open portion 72, and then the discharge circuit 32 is shorted by the short circuit portion 71.

That is, when the detection circuit 46 detects an abnormal voltage in any of the battery cells 41 to 44, the battery pack 40 first outputs a switching signal to the second switch element 62. The second switch element 62 controls the current of the battery stack 45 so that the second heating element 11 of the open portion 72 is energized. Thereby, the third switching circuit 70 melts the open-side soluble conductor 12 and cuts off the charge / discharge current circuit 33 of the battery stack 45. When the interruption of the charge / discharge current circuit 33 is detected, then the detection circuit 46 outputs a switching signal to the first switch element 61. The first switch element 61 controls the current of the battery stack 45 so that the first heating element 2 of the short circuit portion 71 is energized. As a result, the first heating element 2 is energized, and the short-circuit side soluble conductor 2 is fused, whereby the first and

second electrodes

Thus, the battery pack 40 in which the third switching circuit 70 is incorporated cuts off the charge / discharge current circuit 33 of the battery stack 45 which has caused an abnormality, and the battery stack in which a large electric energy corresponding to the battery capacity is stored. The 45 current paths are switched to the discharge circuit 32 provided with a protective resistance. Therefore, the battery pack 40 can be discharged until the internal battery cells drop to a safe voltage after the use is stopped.

[Built-in protection element]
In the third switching circuit 70, as shown in FIG. 17, the protective resistance 31 may be provided on the discharge circuit 32. Alternatively, as shown in FIG. 18, the protective resistance 31 may be built in the short circuit portion 71. . In this case, as shown in FIG. 19, the discharge circuit 32 of the battery pack 40 does not need to have the protective resistor 31.

[Industrial availability]
According to the present invention, by making the first external circuit 23 a light emitting circuit, a sound generating circuit, a circuit with electric signal generation or the like, the state in which the open circuit 10 or the open portion 72 operates can be notified as an alarm to the outside It can also be applied to an open circuit with an alarm function.

Further, according to the present invention, the present invention can be applied as a circuit for activation of various devices and software. For example, the first external circuit 23 is a functional circuit of various devices and software, the second external circuit 24 is a circuit in which a part of the function is limited, and the initial setting is a second function limited function. External circuit 24 is connected. When the user performs a license contract procedure to activate the device, the user is switched to the first external circuit 23 which is a functional circuit of the device.

Further, according to the present invention, the present invention can be applied as an information security circuit for protecting information of a database. For example, the second external circuit 24 is a functional circuit connected to a database, the first external circuit 23 is configured as a circuit separated from the database, and the database is set via the second external circuit 24 in initialization. It is supposed to be accessible to When hacking or cracking is detected, switching is made to the first external circuit 23 separated from the database in order to protect information in the database.

In the present invention, since switching to the functional circuit is performed by melting the short-circuit side soluble conductor 3 and the open-side soluble conductor 12, it is possible to control the switching of the function physically and irreversibly. Therefore, unlike a case where a circuit is electronically switched by software, it is possible to improve the switching failure due to a malfunction or to improve the vulnerability to an unauthorized switching due to hacking, cracking or the like.

DESCRIPTION OF SYMBOLS 1 short circuit, 2 1st heat generating body, 3 short circuit side soluble conductor, 4 switches, 5 1st electrode, 6 2nd electrode, 7 1st heat generating electrode, 10 open circuit, 11 2nd heat generation Body, 12 open side soluble conductor, 13 third electrode, 14 fourth electrode, 15 second heat generating electrode, 16 connection end electrode, 21 short circuit element, 22 open element, 23 first external circuit, 24 Second external circuit, 25 power supply circuit, 26 switch elements, 30 first switching circuit, 31 protection resistors, 32 discharge circuits, 33 charge / discharge current circuits, 40 battery packs, 41 to 44 battery cells, 45 battery stacks, 46 Detection circuit, 50 charge and discharge control circuit, 51 current control element, 52 current control element, 55 charge circuit, 60 second switching circuit, 61 first switch element, 62 first Switch element, 70 a third switching circuit, 71 short circuit portion 72 opening

Claims

A first heat generating body that generates heat when a current flows, a short circuit side soluble conductor whose one end is connected to the first heat generating body and the other end is connected to the main circuit, and one end is the short circuit side soluble conductor And a switch connected to the main circuit and the other end connected to the first circuit, and the short circuit side soluble conductor is fused and cut by the heat generated by the first heating element, A short circuit which shorts the switch by a molten conductor;
An open-side soluble conductor connected to a second heating element that generates heat when a current flows and to the second heating element, and having one end connected to the second circuit and the other end connected to the main circuit And an open circuit for melting the open-side soluble conductor by the heat generated by the second heating element,
At one end of the second heat generating body, a switch element for receiving a switching signal and causing a current to flow from the main circuit to the second heat generating body is connected.
Connecting the open end of the first heating element of the short circuit to the connection end of the second heating element of the open circuit and the open-side soluble conductor;
When the switch element operates, the second heating element of the open circuit is energized and generates heat to melt the open-side soluble conductor, and the main circuit and the second circuit are disconnected.
The first heat generating element of the short circuit is energized and generates heat by melting of the open side soluble conductor, the short circuit side soluble conductor melts, and the switch is shorted, thereby the main circuit and the first circuit. A switching circuit that is energized with the circuit.
The main circuit is a power supply circuit having a battery stack,
The first circuit is a discharge circuit that discharges the electricity of the battery stack, and the second circuit is a charge / discharge current circuit of the battery stack,
The power supply circuit and the charge / discharge current circuit are disconnected by the open circuit to stop charging the battery stack, and the power supply circuit and the discharge circuit are shorted by the short circuit to accumulate in the battery stack The switching circuit according to claim 1, wherein the switched electric energy is discharged.
3. The switching circuit according to claim 2, wherein the other end of the switch of the short circuit is provided with a protective resistance for discharging the electrical energy stored in the battery stack at a maximum discharge current of the battery cell or less.
3. The switch according to claim 2, wherein said discharge circuit is connected to the other end of said switch of said short circuit, wherein a protective resistance for discharging the electrical energy stored in said battery stack below the upper limit discharge current of the battery cell. circuit.
The open side soluble conductor is connected to the first open side soluble conductor whose one end is connected to the main circuit and whose other end is connected to the second heat generating body, and one end is connected to the second circuit and the other The switching circuit according to any one of claims 1 to 4, further comprising a second open-side soluble conductor whose end is connected to the second heating element.
A first heat generating body that generates heat when a current flows, a short circuit side soluble conductor whose one end is connected to the first heat generating body and the other end is connected to the main circuit, and one end is the short circuit side soluble conductor And a switch connected to the main circuit and the other end connected to the first circuit, and the short circuit side soluble conductor is fused and cut by the heat generated by the first heating element, A short circuit which shorts the switch by a molten conductor;
An open-side soluble conductor connected to a second heating element that generates heat when a current flows and to the second heating element, and having one end connected to the second circuit and the other end connected to the main circuit And an open circuit for melting the open-side soluble conductor by the heat generated by the second heating element,
A first switch element is connected to one end of the first heat generating body for receiving a switching signal and causing a current to flow from the main circuit to the first heat generating body,
At one end of the second heat generating body, a second switch element is connected, which receives a switching signal and causes a current to flow from the main circuit to the second heat generating body,
When the second switch element operates, the second heat generating element of the open circuit is energized and generates heat to melt the open-side soluble conductor, and the main circuit and the second circuit are disconnected. And
When the first switch element operates, the first heating element of the short circuit is energized and generates heat to melt the short circuit side soluble conductor, thereby shorting the switch, the main circuit and the main circuit Switching circuit through which the first circuit is energized.
The main circuit is a power supply circuit having a battery stack,
The first circuit is a discharge circuit that discharges the electricity of the battery stack,
The second circuit is a charge / discharge current circuit of the battery stack,
The second switch is operated to interrupt the power supply circuit and the charge / discharge current circuit by the open circuit to stop the charging of the battery stack, and then the first switch element is operated to cause the short circuit. The switching circuit according to claim 6, wherein the power supply circuit and the discharge circuit are short-circuited to discharge the electrical energy stored in the battery stack.
8. The switching circuit according to claim 7, wherein the other end of said switch of said short circuit is provided with a protective resistor for discharging at a level not exceeding the upper limit discharge current of the electric energy battery cell stored in said battery stack.
The discharge circuit is provided, between the other end of the switch of the short circuit, with a protective resistance for discharging the electrical energy stored in the battery stack at a maximum discharge current of the battery cell or less. Item 7. The switching circuit according to Item 7.
7. The device according to claim 6, wherein the first switch element is operated to short the first circuit by the short circuit, and then the second switch element is operated to disconnect the second circuit by the open circuit. Switching circuit.
7. The apparatus according to claim 6, wherein the second switch element is operated to cut off the second circuit by the open circuit, and then the first switch element is operated to short the first circuit by the short circuit. Switching circuit.
The open side soluble conductor is connected to the first open side soluble conductor whose one end is connected to the main circuit and whose other end is connected to the second heat generating body, and one end is connected to the second circuit and the other The switching circuit according to any one of claims 6 to 11, further comprising a second open-side soluble conductor whose end is connected to the second heating element.
A first heating element that generates heat when current flows, a short-circuited soluble conductor whose one end is connected to the first heating element and whose other end is connected to the first circuit, and one end is the short-circuit side A switch connected to the molten conductor and connected to the first circuit, and having the other end connected to the main circuit, and the short circuit side soluble conductor is fused and cut off by the heat generated by the first heating element A shorting portion shorting the switch by the molten conductor;
A second heating element that generates heat when a current flows, and the second heating element are connected and one end is connected to the other end of the switch and the main circuit, and the other end is connected to the second circuit And an open portion for melting and cutting the open side soluble conductor by the heat generated by the second heat generating body,
The first heat generating body is connected to a first switch element which receives a switching signal and causes a current to flow from the main circuit to the first heat generating body,
The second heat generating body is connected to a second switch element which receives a switching signal and causes a current to flow from the main circuit to the second heat generating body.
When the second switch element operates, the second heating element in the open portion is energized and generates heat, and the open-side soluble conductor is fused and the main circuit and the second circuit are disconnected. And
When the first switch element operates, the first heating element of the short circuit part is energized and generates heat to melt the short circuit side soluble conductor, thereby shorting the switch, the main circuit and the main circuit Switching circuit through which the first circuit is energized.
The main circuit is a power supply circuit having a battery stack,
The first circuit is a discharge circuit that discharges the electricity of the battery stack,
The second circuit is a charge / discharge current circuit of the battery stack,
The second switch is operated to interrupt the power supply circuit and the charge / discharge current circuit by the open portion to stop the charging of the battery stack, and then the first switch element is operated to short the portion The switching circuit according to claim 13, wherein the power supply system circuit and the discharge circuit are short-circuited to discharge the electrical energy stored in the battery stack.
15. The switching circuit according to claim 14, wherein a protection resistor is provided at the other end of the switch in the short circuit portion to discharge the electrical energy stored in the battery stack at a maximum discharge current of the battery cell or less.
The discharge circuit is provided, between the other end of the switch in the short circuit portion, with a protective resistance for discharging the electrical energy stored in the battery stack at a maximum discharge current of the battery cell or less. The switching circuit according to Item 14.
14. The method according to claim 13, wherein the first switch element is operated to short the first circuit by the short circuit portion, and then the second switch element is operated to interrupt the second circuit by the open portion. Switching circuit.
14. The method according to claim 13, wherein the second switch element is operated to cut off the second circuit by the open section, and then the first switch element is operated to short the first circuit by the short circuit section. Switching circuit.
The open side soluble conductor is connected to the first open side soluble conductor whose one end is connected to the second circuit and the other end is connected to the second heating element, and one end is connected to the main circuit and the other The switching circuit according to any one of claims 13 to 18, further comprising a second open-side soluble conductor whose end is connected to the second heating element.
The switching circuit according to any one of claims 1, 6, and 13, wherein the first circuit is a light emitting circuit, a sound generating circuit, or a circuit with electronic signal generation.