JP3371785B2 - Battery application circuit - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a storage battery application circuit for use in which one or more storage batteries such as a lithium battery, an electric double layer capacitor, and a pack battery in which a plurality of unit batteries are connected in series and parallel are used in series, In particular, the present invention relates to a charging / discharging device using multiple series of capacitors having an open-type protection element or a safety device inside the capacitor, and a capacitor application circuit suitable for an electric device using these.

[0002]

2. Description of the Related Art Conventionally, there has been a lithium secondary battery having a built-in pressure switch that opens an electrode terminal and shuts off an electric current when the battery internal pressure rises. For example, JP-A-6-215746.

FIG. 11 is a cross-sectional view of a conventional safety device. In the figure, 1101 is a metal safety valve, 11
02 is an insulating ring, 1103 is a perforated metal terminal plate, 11
Reference numeral 04 is a metal lead mounting plate, 1105 is a bent portion, 1
Reference numeral 106 is a welded portion.

When the internal pressure of the secondary battery rises due to a short circuit, overcharge or reverse charge, it is transmitted to the metal safety valve 1101 through the metal lead mounting plate 1104, the metal perforated terminal plate 1103, and the ventilation holes provided in the insulating ring 1102. To be Since the outer peripheral portion of the metal safety valve 1101 is caulked by the secondary battery case, when the internal pressure of the secondary battery reaches a predetermined value, the central portion is lifted upward, the bent portion 1105 is inverted and deformed, and the welded portion 1106 is peeled off. Metallic perforated terminal board 110
The connection with 3 is released and the current is cut off.

[0005]

FIG. 12 is a diagram showing a storage battery application circuit in which storage batteries are connected in series. In the figure, 1201 is a storage battery, 1202 is a built-in protection device,
1203 is a secondary battery, 1204 is a second load circuit, 12
Reference numeral 05 is a first load circuit.

Built-in protection device 1202 and secondary battery 1203
The electric storage device 1201 constituted by and is connected in series, and the first load circuit is connected to both ends thereof. Further, the second load circuit 1204 is connected in parallel with a part of the capacitor 1201 connected in series.

In this circuit, even if the structure of the housing is devised so that the plus and the minus of the condenser are not mistakenly attached, even if the upper condenser 1201 is removed or the condenser is attached to the lower side. From the above, a reverse bias is applied to the second load circuit 1204,
This will damage the second load circuit 1204. Even if the capacitor 1201 is attached from the upper battery 1201 and fixed so as not to be removed, in particular, in a battery having a built-in protection device 1202 such as a conventional lithium secondary battery, Built-in protection device 120
When 2 is opened due to overcurrent or the like, a reverse bias is similarly applied to the second load circuit 1204, which damages the second load circuit 1204. Therefore, the second load circuit 1204 needs to be designed to withstand reverse bias.

Furthermore, when the number of capacitors 1201 in series increases, or when the voltage of the capacitor 1201 on the lower side is high,
When the connection of the upper power storage device 1201 is broken, a reverse bias is applied to the second load circuit 1204 and a voltage higher than the voltage of the upper power storage device 1201 is applied. Therefore,
The second load circuit 1204 needs to be designed to withstand reverse bias and high voltage.

In addition, in a general storage battery application circuit using a rechargeable storage battery, the first load circuit is a charge / discharge circuit. In this case, when the upper battery 1201 is cut off due to overcharge, a high forward bias voltage is applied to the second load circuit 1204. Therefore, the second load circuit 1204
Must be able to withstand the voltage of the total number of series connected to the reverse bias minus the voltage of the capacitors connected in parallel, and the voltage of the forward bias to compensate for overcharge minus the voltage of the other capacitors. Need to be designed. But,
When the voltage rating of the second load circuit 1204 is set so as to satisfy the above requirement, the second load circuit 1204 becomes large and the cost becomes high. Further, it is practically impossible to realize a voltage rating that satisfies these requirements in a high-voltage power storage device in which a large number of power storage devices are connected in series. If the negative second load circuit 1204 is used without the sufficient voltage rating, the second load circuit 1204 is damaged and the dangerous state occurs when the upper battery 1201 is cut off.

Particularly, when the second load circuit 1204 is composed of a semiconductor device, the damage state is a short-circuit type. Therefore, the upper battery 12
01 is bypassed, and the short circuit fault part between the remaining capacitor 1201 and the second load circuit 1204, and the first load circuit 12
A current path 05 is newly formed, and there is a high possibility that the other constituent circuit elements are further damaged.

For example, the first load circuit often includes a voltage regulator to keep the voltage obtained from the capacitor constant. Particularly, in a general lithium secondary battery, the voltage between terminals greatly changes from 2.5 V to 4.2 V, and therefore a voltage regulator is almost indispensable.

In this case, the short-circuited second load circuit 120
4, the voltage regulator absorbs the voltage decrease of the upper battery 1201 and the circuit operates. Then,
The current of the lower power storage device 1201 increases and further damages the lower power storage device 1201 and the first load device 1205.

In a general storage battery application circuit, it is rare that the connection point connected in series is connected to the second load circuit. However, various problems as described above occur when trying to connect and use a battery that is difficult to handle like a lithium secondary battery and needs to be monitored for each connection in series. In particular, when a large number of conventional lithium secondary batteries are connected in series and used, a protective device built therein and a voltage regulator required due to a large voltage change pose a problem.

The present invention has been made to solve the above problems, and reduces the voltage rating of a load circuit connected to a part of a series-connected power storage device to protect the load circuit, the power storage device, and the entire circuit. In addition, it is an object of the present invention to provide a low-cost, small-sized, safe, cheap-handling, highly reliable battery application circuit that does not depend on the mounting order of the batteries.

[0015]

SUMMARY OF THE INVENTION A storage battery application circuit according to the present invention has a storage battery train connected in series, a first load circuit connected to both ends of the storage battery train, and a number less than the number of the storage battery trains in series. Second connected to the series of the capacitors
In the circuit including the load circuit, a protection circuit for preventing reverse bias of the second load circuit is provided in series with the second load circuit. Alternatively, a voltage detection circuit that detects the voltage of the second load circuit is provided in parallel with the second load circuit, and a protection circuit that includes a switch that opens and closes according to the output of the voltage detection circuit is provided in the second circuit. It is provided in series with the load circuit of. Alternatively, a voltage detection circuit that detects the voltage of the second load circuit and a bypass circuit that opens and closes according to the output of the voltage detection circuit are provided in parallel with the second load circuit, and consist of a current-sensitive fuse. The protection circuit is the second
It is provided in series with the load circuit of. When a plurality of second load circuits are connected in series, the number of series connections is divided into predetermined groups. Further, a capacitor state communication circuit may be provided between the second load circuit or the grouped second load circuit and the protection circuit.

In the storage battery application circuit having the above structure, when a voltage exceeding the rated voltage is applied to the second load circuit when the storage battery is attached or detached, or when the built-in protection device is operating, the first load circuit is operated in accordance with the applied voltage. A protection circuit provided in series with the second load circuit electrically disconnects the second load circuit from the capacitor. Alternatively, according to the applied voltage, a bypass circuit provided in parallel with the second load circuit is turned on, and the second load circuit is turned on.
The current-sensitive fuse provided in series with the load circuit of 1 is cut off to electrically disconnect the second load circuit from the capacitor. Further, the storage state communication circuit outputs that the second load circuit has been disconnected. With these, the voltage rating of the load circuit connected to the series-connected capacitors is reduced, the load circuit, the capacitors, and the entire circuit are protected, and the order of mounting the capacitors is not limited, low cost, small size, It is possible to realize a battery application circuit that is safe, easy to handle, and highly reliable.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. In the figure, the same part is 2
The same reference numerals are given to those having three or more, and the description thereof is omitted. FIG. 1 is a diagram showing a first embodiment of the present invention. In the figure, 101 is a storage battery, 102 is a built-in protection device, 103 is a secondary battery, 104 is a second load circuit,
Reference numeral 05 is a first load circuit, and 107 is a protection circuit.

A storage device 101 composed of a built-in protection device 102 and a secondary battery 103 is connected in series, and a first load circuit is connected to both ends of the storage device 101. Also, the second load circuit
104 is connected in parallel with a part of the battery 101 connected in series. Then, the protection circuit 107 is the second load circuit 1
04 is connected in series.

Here, the protection circuit 107 is composed of an N-type MOS transistor, and the gate thereof is the second load circuit 10.
4 is connected to the positive side of the battery 101 that is connected in parallel.

When the upper power storage device 101 is removed first, or when the lower power storage device 101 is attached first, and the built-in protection device 1 for the upper power storage device 101.
If 02 is opened due to overcurrent, etc., the protection circuit 107
The gate potential of the N-type transistor becomes low and the transistor turns off. On the contrary, when the upper battery 101 is attached and the built-in protection device 102 is conducting,
The gate potential of the N-type MOS transistor becomes high and the transistor turns on. That is, the second load circuit 10
When a reverse bias is applied to No. 4, the protection circuit 107 cuts off the connection and prevents the reverse bias of the second load circuit. Then, in the forward bias, it conducts and makes the connection effective.

Here, a protection circuit 1 for preventing reverse bias
07 can also be achieved with a diode. However, since the MOS transistor has a smaller voltage drop, it is more suitable than the diode.

As described above, in this capacitor application circuit, the voltage rating of the second load circuit 104 can be reduced to the value of only forward bias, and the cost and size of the second load circuit 104 can be reduced. it can. Further, the protection circuit 107 also has one N
Type MOS transistor and low cost and small size can be realized. Further, the storage battery 101 can be freely attached and detached, and the easiness of handling can be improved.

FIG. 2 is a diagram showing a second embodiment of the present invention. Voltage detection circuit 201 composed of operational amplifier
Are connected in parallel with the second load circuit 104. Further, the protection circuit 107 includes an N-type MOS transistor and a P-type M
It is configured by connecting OS transistors in series. The output of the voltage detection circuit 201 is connected to the gates of the N-type MOS transistor and the P-type MOS transistor.

When the upper power storage device 101 is removed first, or when the lower power storage device 101 is attached first, and the built-in protection device 1 for the upper power storage device 101.
When 02 is opened due to overcurrent, voltage detection circuit 2
The input of 01 becomes negative, and its output also outputs an amplified negative value. Then, the N-type MOS transistor turns off.
Then, the connection of the second load circuit 104 is cut off.

When the power storage device 101 is a rechargeable power storage device and the first load circuit is a charging / discharging circuit, the built-in protection device 102 of the upper power storage device 101 is shut off due to overcharge, and the second load circuit 104 is provided. Even when a high forward bias voltage is applied to the P-type MOS transistor,
Then, the connection of the second load circuit 104 is cut off.

The voltage value for cutting off the connection of the second load circuit 104 by the reverse bias and the forward bias exceeding the rating can be adjusted by the threshold voltage of the MOS transistor or the gain of the operational amplifier. Therefore, it is possible to reduce the value of the rated voltage of the forward bias that is guaranteed when the second load circuit 104 is abnormal.

On the other hand, when the voltage within the rating is applied to the second load circuit 104, both the N-type MOS transistor and the P-type MOS transistor are turned on to enable the connection of the second load circuit 104.

As described above, in this capacitor application circuit, the reverse bias of the second load circuit 104 can be prevented, and the value of the rated voltage of the forward bias that can be guaranteed at the time of abnormality can also be reduced, and the low load of the second load circuit 104 can be reduced. Cost and size can be reduced. Further, the electric storage pack 101 can be freely attached and detached, and the easiness of handling, safety, and reliability can be improved.

FIG. 3 is a diagram showing a third embodiment of the present invention. Reference numeral 301 is a comparator, and 302 is a reference voltage generation circuit. Comparator 301 and voltage detection circuit 20
1 (op-amp) is connected in parallel with the second load circuit 104, and these outputs are connected to the control terminal of the protection circuit 107 composed of an N-type MOS transistor. The reference voltage generation circuit 302 is composed of a Zener diode, and is set to the forward bias rated voltage of the second load circuit 104. Further, the comparator 301 compares the applied voltage of the second load circuit 104 with the voltage of the reference voltage generation circuit 302. When the applied voltage of the second load circuit 104 exceeds the voltage of the reference voltage generation circuit 302, that is, the forward bias rated voltage of the second load circuit 104, the comparator 301 inverts the output to a low potential, and The protection circuit 107 connected to is turned off, and the connection of the second load circuit 104 is cut off.

Further, by comparing with the reference voltage generation circuit 302 by the comparator 301, the protection circuit 107 can be controlled more accurately.

Then, when a reverse bias is applied to the second load circuit 104, the output of the voltage detection circuit 201 outputs an amplified negative value. Then, the N-type MOS transistor is turned off, and the connection of the second load circuit 104 is cut off.

On the other hand, when the voltage within the rating is applied to the second load circuit 104, the N-type MOS transistor is turned on to enable the connection of the second load circuit 104.

As described above, in the present capacitor application circuit, the reverse bias of the second load circuit 104 can be prevented, and the value of the rated voltage of the forward bias that is guaranteed at the time of abnormality can be accurately reduced.
The cost and size of the second load circuit 104 can be reduced. Further, the electric storage pack 101 can be freely attached and detached, and the easiness of handling, safety, and reliability can be improved.

FIG. 4 is a diagram showing a fourth embodiment of the present invention. A bypass circuit 401 including an N-type MOS transistor and a P-type MOS transistor connected in series and a voltage detection circuit 201 including an operational amplifier are both connected in parallel with the second load circuit 104. A protection circuit 107 formed of a current-sensitive fuse is connected in series with the second load circuit 104.

When the voltage within the rating is applied to the second load circuit 104, the bypass circuit 401 is off, and the connection of the second load circuit 104 is validated.

However, when a reverse bias or a forward bias exceeding the rated voltage is applied to the second load circuit 104, the N-type MOS transistor and the P-type MOS transistor are turned on, and the second load circuit 104 is connected. Short circuit. Then, a current more than the rated current flows through the current-sensitive fuse,
The current-sensitive fuse is blown to cut off the connection of the second load circuit 104. Then, even if the abnormality is avoided and the voltage becomes normal, the connection of the second load circuit 104 is not restored unless the protection circuit 107 is replaced. Therefore, it is effective for an electric device that needs to handle an abnormality more carefully.

Further, the bypass circuit 401 of this circuit can be used also as a balance compensation circuit used for equalizing the voltage difference between the capacitors connected in series, so that the number of parts can be reduced, the size can be reduced, and the size can be reduced. Cost can be reduced.

As described above, in the capacitor application circuit of the present invention, the reverse bias of the second load circuit 104 can be prevented and the value of the rated voltage of the forward bias that is guaranteed in the case of an abnormality can be reduced, and the second load circuit 104 and the bypass circuit can be reduced. Cost reduction of the circuit 401,
The size can be reduced. Further, the electric storage pack 101 can be freely attached and detached, and the easiness of handling, safety, and reliability can be improved. In particular, it is effective for an electric device that needs to handle an abnormality more carefully.

FIG. 5 is a diagram showing a fifth embodiment of the present invention. Bypass circuit 4 consisting of N-type MOS transistor
01, a voltage detection circuit 201 including an operational amplifier, a second
Applied voltage of the load circuit 104 and the reference voltage generation circuit 302
A comparator 301 for comparing the voltage of the second load circuit 104 is connected in parallel with the second load circuit 104. A protection circuit 107 including a current-sensitive fuse is connected in series with the second load circuit 104.

When the voltage within the rating is applied to the second load circuit 104, the bypass circuit 401 is off, and the second load circuit 104 validates the connection.

However, when a reverse bias or a forward bias exceeding the rated voltage is applied to the second load circuit 104, the N-type MOS transistor turns on, and the second load circuit 1
Short circuit between 04. Then, a current higher than the rated current flows through the current-sensitive fuse, and the current-sensitive fuse melts down.
The connection of the second load circuit 104 is cut off. Then, even if the abnormality is avoided and the voltage becomes normal, the connection of the second load circuit 104 is not restored unless the protection circuit 107 is replaced. Therefore, it is effective for an electric device that needs to handle an abnormality more carefully.

Further, the bypass circuit 401 of this circuit can be shared with a balance compensation circuit used for equalizing the voltage difference between the capacitors connected in series, and the number of parts can be reduced, the size can be reduced, and the size can be reduced. Cost can be reduced.

By comparing the reference voltage generating circuit 302 with the comparator 301, the bypass circuit 401 can be controlled more accurately.

As described above, in the present battery application circuit, the reverse bias of the second load circuit 104 can be prevented, and the value of the rated voltage of the forward bias that is guaranteed at the time of abnormality can be accurately reduced.
The cost and size of the second load circuit 104 and the bypass circuit 401 can be reduced. In addition, the battery 10
1 can be freely attached and detached, and it is possible to improve ease of handling, safety, and reliability. In particular, it is effective for an electric device that needs to handle an abnormality more carefully.

FIG. 6 is a diagram showing a sixth embodiment of the present invention. In the figure, 601 is a piezoelectric switch. The piezoelectric switch 601 is composed of a piezoelectric element and a switch, the piezoelectric element is connected in parallel with the second load circuit 104, and the switch section is inserted in series with the second load circuit 104.
When a voltage is applied, this piezoelectric element expands and contracts in a certain direction according to the voltage value. Then, the switch is opened and closed by this expansion and contraction movement. Therefore, when the rated voltage of the second load circuit 104 is exceeded, the movement amount of the piezoelectric element is set so as to open the switch.

As a result, in the storage battery application circuit of the present invention, the second
The voltage rating of the load circuit 104 can be reduced, and the cost and size of the second load circuit 104 can be reduced. Also, the protection circuit 107 can be realized at low cost and in a small size.
Then, the storage battery 101 can be freely attached and detached, the easiness of handling can be improved, and the safety and reliability can be improved.

FIG. 7 is a diagram showing a seventh embodiment of the present invention. The Zener diode 701 having the cathode connected to the positive side of the second load circuit 104 is connected to the second load circuit 10
4 is provided in parallel with the second load circuit 104 and a protection circuit 107 including a current-sensitive fuse is inserted in series with the second load circuit 104.

Forward bias to the Zener diode 701,
Alternatively, when a reverse bias equal to or higher than the breakdown voltage is applied, that is, a reverse bias is applied to the second load circuit 104, or
When a forward bias equal to or higher than the rated voltage is applied, the Zener diode 701 becomes conductive and short-circuits the second load circuits 104. Then, a current larger than the rated current flows through the current-sensitive fuse, the current-sensitive fuse is melted, and the connection of the second load circuit 104 is cut off.

Then, even if the abnormality is avoided and the voltage becomes normal, the connection of the second load circuit 104 is not restored unless the protection circuit 107 is replaced. Therefore, it is effective for an electric device that needs to handle an abnormality more carefully.

As described above, in the present battery application circuit, the voltage rating of the second load circuit 104 can be reduced, and the cost and size of the second load circuit 104 can be reduced.
Also, the protection circuit 107 can be realized at low cost and in a small size. Then, the storage battery 101 can be freely attached and detached, the easiness of handling can be improved, and the safety and reliability can be improved.

FIG. 8 is a diagram showing an eighth embodiment of the present invention. The Zener diode 701 having the cathode connected to the positive side of the second load circuit 104 is connected to the second load circuit 10
4 is provided in parallel, and a protection circuit 107 made of PTC is inserted in series with the second load circuit 104.

When a current exceeding the rated current flows in the PTC,
It is an element whose resistance rapidly increases due to self-heating.

Forward bias to the Zener diode 701,
Alternatively, when a reverse bias equal to or higher than the breakdown voltage is applied, that is, when a reverse bias equal to or higher than the rated voltage is applied to the second load circuit 104, the Zener diode 701 is turned on and the second load circuit is turned on. Short circuit between 104. Then, a current exceeding the rated current flows through the PTC, and P
The resistance of TC increases rapidly and the second load circuit 104 cuts off the connection. Then, when the abnormality is avoided, the voltage becomes normal, and the temperature of the PTC decreases, the resistance decreases, and the connection of the second load circuit 104 is restored.

As described above, in the present battery applied circuit, the voltage rating of the second load circuit 104 can be reduced, and the cost and size of the second load circuit 104 can be reduced.
Also, the protection circuit 107 can be realized at low cost and in a small size. Then, the storage battery 101 can be freely attached and detached, the easiness of handling can be improved, and the safety and reliability can be improved.

FIG. 9 is a diagram showing a ninth embodiment of the present invention. In the figure, reference numeral 901 denotes a capacitor circuit row group, 9
02 is a battery state communication circuit, 903 is a PWM inverter,
A converter, 904 is a step-up / down chopper, and 905 is a control microcomputer.

Second load circuit 104 and capacitor 101
Are connected in series in units of four, and these are connected in parallel in a ladder shape via the protection circuit 107. Also, 4
A voltage detection circuit 201 and a comparator 301 for comparing with a reference voltage generation circuit 302 are connected in parallel to each of the second load circuits 104 divided into groups.
It is connected to the control terminal of each protection circuit 107. A battery state communication circuit 902 is connected to both ends of the second load circuit 104 connected in series in units of four. Then, the first load circuit 105 is connected to both ends of which the electric storage device circuit row group 901 and the electric storage device row configured by these are further connected in series.

Here, the protection circuit 107 is an N-type MOS transistor, and its control circuit is the voltage detection circuit 201, the reference voltage generation circuit 302, and the comparator 301.
The other circuit configurations described above may be used.

The first load circuit 105 is a charging / discharging device, and is mainly a PWM inverter / converter 903.
It is composed of a step-up / down chopper 904 and a control microcomputer 905. And, in the whole circuit, convert AC into DC,
It has the function of storing electricity and the function of converting the stored direct current into alternating current and outputting it.

Now, assuming that the battery 101 is a lithium secondary battery, the second load circuit 104 includes a detection circuit for detecting overcharge, overdischarge, and temperature of each battery 101, and each battery 10
1 corresponds to a balance compensation circuit that corrects variations in current and voltage. In particular, the detection circuit corresponds to a dedicated IC corresponding to the connection of 4 series or less. Then, these detection circuits can also serve as the voltage detection circuit 201, the comparator 301, the reference voltage generation circuit 302, or the bypass circuit 401.

In this circuit, when outputting alternating current,
The DC of the battery 101 is boosted by the step-up / down chopper 904 and converted into AC by the PWM inverter converter 903. At this time, the voltage per unit of the lithium secondary battery generally changes from 2.5V to 4.2V,
As shown in the figure, the difference is even larger with 13.6V in total with 8 units in series. Therefore, the output voltage of the buck-boost chopper 904 is detected and fed back to the boost chopper operation to stabilize the output voltage.

If, at the time of assembling this circuit, a certain capacitor 101
Is removed, or when the last battery 101 is attached, or when the built-in protection device 102 of the battery 101 during output operation is opened due to overcurrent or the like, the operation is as follows.

First, the remaining load 104 is connected to the second load circuit 104 which is connected in parallel with the focus of charge 101.
, A reverse bias voltage of up to −29.4 V is likely to be applied. However, at the moment when the reverse bias is applied to the second load circuit 104, the voltage detection circuit 201 outputs a low voltage, turning off the protection circuit 107 composed of an N-type MOS transistor to cut off the connection. However, the remaining capacitor 101 and the second load circuit 104 connected in series
2 is present, the connection of the second load circuit 104 to which the reverse bias is applied next is cut off. Then, in the same manner, the next second load circuit 104 is cut off in the same manner, and eventually,
Each of the second load circuits 104 divided into groups of four is shut off. In addition, the connection between the battery array and the second load circuit 104 and the first load circuit 105 is completely cut off.

Next, when charging the battery array, the PWM inverter / converter 903 converts the AC input into DC. The converted direct current is charged by lowering the rated voltage of the battery array by the buck-boost chopper.

If the buck-boost chopper 904 malfunctions or malfunctions and a voltage exceeding the rated voltage of the second load circuit 104 and the capacitor 101 is applied, the comparator 30
1 outputs a low potential, and the protection circuit 107 cuts off the connection between the second load circuit 104 and the capacitor 101. Then, when there is a path that passes through the remaining second load circuit 104, the next second load circuit 104 is similarly cut off in the same manner, and as a result, each second load circuit 104 is divided into four second groups. The load circuit 104 is shut off. In addition, the connection between the battery array and the second load circuit 104 and the first load circuit 105 is completely cut off.

On the other hand, while the abnormality occurs as described above and the connection of the second load circuit 104 is cut off, the battery state communication circuit 902 is powered off, and the information is stored in the control microcomputer.
Passed to 905. Then, receiving this information, the control microcomputer 905 stops the PWM inverter converter 903 and the step-up / down chopper 904. This allows
It is also possible to protect the entire device. Especially for the maximum output voltage of a single cell of 4.2V,
In a circuit with a large fluctuation of 13.6V, the first load circuit 105 will operate normally even if several unit cells are cut off, and other circuits will be destroyed. Therefore, in the case where the storage device 101 is disconnected as described above, detecting the information and stopping the entire device not only protects a partial circuit but also the safety, reliability and handling of the entire device. Greatly contributes to the improvement of sex. As described above, in the present storage battery application circuit, even when the second load circuit 104 is connected in series, the second load circuit can be blocked and protected in units of four series divided into groups. Then, the withstand voltage of the second load circuit 104, the voltage detection circuit 201, and the comparator 301 can be reduced to four series. In particular, the maximum voltage of the four series is 16.8V, which is compatible with the rated voltage of general-purpose semiconductor devices. For this reason,
The second load circuit and voltage detection circuit 201, the reference voltage generation circuit 302, the comparator 301, or the bypass circuit 401 can be realized by the same IC. Then, the cost and size of the second load circuit 104 can be reduced. Further, the electric storage pack 101 can be freely attached and detached, and the easiness of handling, safety, and reliability can be improved.

FIG. 10 is a diagram showing a tenth embodiment of the present invention. In the figure, 1001 is an analog switch,
1002 is an isolation amplifier.

The input of the isolation amplifier 1002 is connected via an analog switch 1001 to each connection point of the capacitors 101 connected in series in units of four. The output of the isolation amplifier 1002 and the input of the analog switch 1001 are connected to the control microcomputer 905. And
The first load circuit 105 is connected to both ends of the electric storage device circuit row group 901 and the electric storage device row that are configured in series.

The isolation amplifier 1002 detects the voltage between the terminals of each battery 101, and the analog switch 1001 also serves as a selection switch of the battery 101 for detecting the voltage and a balance compensation.

In this circuit, at the time of assembly, a certain electric storage device 1
01 is removed, or the last battery 101 is attached, the built-in protection device 102 of the battery 101 during output operation is opened due to overcurrent, or the buck-boost chopper 904 malfunctions or malfunctions. If an abnormal voltage is applied, the control microcomputer 905
Abnormality is determined from the voltage of the isolation amplifier 1002, and all analog switches 1001 are shut off. Further, the PWM inverter / converter 903 and the buck-boost chopper 904 are stopped. As a result, the input rating of the isolation amplifier 1002 can reduce the voltage for four series. In addition, the isolation amplifier 1002 includes the voltage detection circuit 201 and the battery state communication circuit 902, the analog switch 1001 includes the selection switching circuit, the balance compensation circuit, and the protection circuit 107, and the control microcomputer 905 includes the reference voltage generation circuit 302 and the comparator 301. It is possible to combine. Therefore, the number of parts can be reduced, the cost can be reduced, and the size can be reduced.

As described above, in the present battery application circuit, the withstand voltage of the insulation amplifier 1002 can be reduced to 4 series, and by sharing each circuit, the cost and size can be reduced. Further, the electric storage pack 101 can be freely attached and detached, and the easiness of handling, safety, and reliability can be improved.

[0071]

As described above, according to the present invention, the voltage rating of the load circuit connected to the series-connected capacitors is reduced, the load circuit, the capacitors, and the entire circuit are protected, and the capacitor It is possible to provide a low-cost, small-sized, safe, easy-to-handle, and highly reliable battery application circuit that can be installed in any order.

Therefore, in particular, a lithium battery, an electric double layer capacitor, a battery pack in which a plurality of unit cells are connected in series and parallel, and a charging / discharging device in which an open-type protection device or a safety device are connected in series in a capacitor, , It is useful in electric devices using these.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention.

FIG. 2 is a diagram showing a second embodiment of the present invention.

FIG. 3 is a diagram showing a third embodiment of the present invention.

FIG. 4 is a diagram showing a fourth embodiment of the present invention.

FIG. 5 is a diagram showing a fifth embodiment of the present invention.

FIG. 6 is a diagram showing a sixth embodiment of the present invention.

FIG. 7 is a diagram showing a seventh embodiment of the present invention.

FIG. 8 is a diagram showing an eighth embodiment of the present invention.

FIG. 9 is a diagram showing a ninth embodiment of the present invention.

FIG. 10 is a diagram showing a tenth embodiment of the present invention.

FIG. 11 is a view showing a cross-sectional view of a conventional safety device.

FIG. 12 is a diagram showing a storage battery application circuit in which storage batteries are connected in series.

[Explanation of symbols]

101, 1201 ... Electric storage device, 102, 1202 ... Built-in protection device, 103, 1203 ... Secondary battery, 104, 1204 ...
Second load circuit, 105, 1205 ... First load circuit,
201 ... Voltage detection circuit, 301 ... Comparator, 302
... reference voltage generation circuit, 401 ... bypass circuit, 601 ...
Piezoelectric switch, 701 ... Zener diode, 901 ...
Condenser circuit row group, 902 ... Battery state communication circuit, 9
03 ... PWM inverter converter, 904 ... Buck-boost chopper, 905 ... Control microcomputer, 1001 ... Analog switch, 1002 ... Insulation amplifier, 1101 ... Metal safety valve, 1102 ... Insulation ring 1103 ... Metal perforated terminal board, 1104 ... Metal lead mounting plate, 1105 ... Bent portion, 1106 ... Welded portion.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akihiro Takanuma 800 Tomita, Ohira-cho, Shimotsuga-gun, Tochigi Prefecture Hitachi Co., Ltd., Tochigi Headquarters, Refrigeration & Thermal Engineering Division (56) Reference JP 3-60336 (JP, A) ) Japanese Patent Laid-Open No. 9-163501 (JP, A) Actual Development Sho 59-52476 (JP, U) Japanese Patent Publication Sho 52-543 (JP, B2) (58) Fields investigated (Int.Cl. ⁷ , DB name) H02J 7/00-7/12 H02J 7/34-7/36

Claims (10)

(57) [Claims] 1. A battery array connected in series, a first load circuit connected to both ends of the battery array, and a second load circuit connected to the battery array having a smaller number of series than the battery array in series. A capacitor application circuit having a load circuit, wherein a protection circuit for preventing reverse bias of the second load circuit is provided in series with the second load circuit. 2. A switch according to claim 1, wherein a voltage detection circuit for detecting the voltage of the second load circuit is provided in parallel with the second load circuit, and the switch opens and closes according to the output of the voltage detection circuit. And a protection circuit that is provided in series with the second load circuit. 3. The voltage detection circuit for detecting the voltage of the second load circuit, the reference value generation circuit for generating a predetermined voltage, the output of the reference value generation circuit, and the second circuit according to claim 1. A comparator for comparing the applied voltage of the load circuit is provided in parallel with the second load circuit, and a protection circuit including a switch that opens and closes according to the output of the voltage detection circuit and the comparator is provided as the second load circuit. A storage battery application circuit characterized in that it is provided in series with. 4. A voltage detection circuit for detecting the voltage of the second load circuit and a bypass circuit which opens and closes according to the output of the voltage detection circuit in parallel with the second load circuit. A storage battery application circuit, comprising a protection circuit provided and provided in series with the second load circuit, the protection circuit including a current-sensitive fuse. 5. The voltage detection circuit for detecting the voltage of the second load circuit, the reference value generation circuit for generating a predetermined voltage, the output of the reference value generation circuit, and the second circuit according to claim 1. A comparator that compares the applied voltage of the load circuit,
A bypass circuit that opens and closes according to the outputs of the voltage detection circuit and the comparator is provided in parallel with the second load circuit, and a protection circuit composed of a current-sensitive fuse is provided with the second load circuit. Characteristic capacitor application circuit. 6. The storage battery application circuit according to claim 1, further comprising a protection circuit formed of a piezoelectric switch that receives an applied voltage of the second load circuit as an input, in series with the second load circuit. . 7. The Zener diode having a cathode connected to the positive side of the second load circuit is provided in parallel with the second load circuit according to claim 1, and a protection circuit including a current fuse is provided in the second load. A capacitor application circuit characterized by being provided in series with the circuit. 8. A Zener diode having a cathode connected to the positive side of the second load circuit is provided in parallel with the second load circuit, and a protection circuit made up of a PTC is provided in the second load circuit. A storage battery application circuit characterized in that it is provided in series with. 9. The electric storage device according to claim 1, wherein the electric storage device, a second load circuit connected in parallel with the electric storage device, and a protection circuit connected in series with the second load circuit are connected in series in a ladder shape. A capacitor having a circuit array and a first load circuit connected to both ends of the capacitor circuit array, wherein the number of series-connected second load circuits in the capacitor circuit array is divided into a predetermined group. Application circuit. 10. The battery state communication circuit according to claim 1, wherein the second load circuit, or the grouped second load circuit and the protection circuit are provided between the second load circuit and the protection circuit. A battery application circuit characterized by.