JP2902200B2 - Battery overcharge / discharge monitoring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an integrated battery,
The present invention relates to an overcharge / discharge monitoring device that monitors overcharge and overdischarge.

[0002]

2. Description of the Related Art Generally, in an assembled battery, a predetermined number of cells are connected in series to form a string, and a predetermined number of strings are connected in parallel to form a block, and the block is used as a basic unit. By connecting a predetermined number in series, an assembled battery is configured.

In a conventional overcharge / discharge monitoring apparatus for a battery pack of this type, a detector 22 for detecting a voltage is connected to each block 21 as shown in FIG. Block overcharge and overdischarge
It was designed to detect one unit. These detectors 2
2 has a complicated configuration including a comparator, a resistor, and the like so that detection is performed independently.

[0004]

As described above, in this conventional overcharge / discharge monitoring apparatus, it is necessary to provide a complicated detector 22 for each block 21 of the assembled battery, which increases the cost and increases the cost. In addition, there has been a problem that the dimensions of the entire battery assembly also increase. In particular, when the present invention is applied to a large-scale battery system such as a power storage battery as in the case of a sodium-sulfur battery, the cost of the monitoring device has been significantly increased and a large installation space has been required.

[0005] The present invention has been made in view of the problems existing in such prior art, and aims at simplifying the structure and reducing the cost. It is an object of the present invention to provide an overcharge / discharge monitoring device for an assembled battery that can reduce the size of the device and reduce the installation space.

[0006]

In order to achieve the above object, according to the present invention, in an assembled battery in which a block composed of unit cells is used as a basic unit and a predetermined number of the blocks are connected in series, an adjacent battery is connected. One or more blocks are connected in parallel with voltage-dividing resistors, and between the circuit between the voltage-dividing resistors and the circuit between the blocks, a battery pack with a detector for detecting voltage or current is overcharged. The gist is a discharge monitoring device.

[0007]

In the overcharge / discharge monitoring apparatus for an assembled battery configured as described above, for example, when one block is overcharged or overdischarged, the block voltage becomes unbalanced with respect to the other block voltages. This state is detected by the detector. Then, such detection operation is performed for each adjacent block, and overcharge and overdischarge of the battery pack are monitored.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an overcharge / discharge monitoring apparatus for an assembled battery according to an embodiment of the present invention;

In this embodiment, as shown in FIG. 2, a single cell 1 is used alone or a predetermined number m of cells are connected in series.
Are connected in series to form a string 1s, and the string 1s is connected in parallel for a predetermined number n of parallels to form a block 1b. Then, as shown in FIG. 1, the block 1b is used as a basic unit,
Are connected in series by a predetermined number to form an assembled battery B.

Further, as shown in FIG. 1, a series circuit of a voltage dividing resistor 2 is connected in parallel to the series circuit of the block 1b. Each resistor 2 has the same resistance value, and they are arranged one by one for each block 1. Another circuit is connected between the circuit between each resistor 2 and the circuit between each block 1, and a current detector 3 is connected to every other circuit. Each current detector 3 is configured by a parallel circuit of a pair of light emitting diodes having different directions.

As shown in FIG. 3, the block voltage of each block 1 undergoes a predetermined change during charging and discharging according to the amount of charging and discharging. When one block 1b is in an overcharged or overdischarged state and its block voltage is unbalanced with that of another adjacent block 1b, the potential difference, that is, the current caused by the voltage division difference, causes one of the detectors 3 to generate a current. A light emitting diode emits light for detection.

An optical fiber 5 is extended between each detector 3 and the centralized monitoring device 4, and light emitted from the detector 3 is guided to the centralized monitoring device 4 via the optical fiber 5. The centralized monitoring device 4 is provided with a lens 6 and a phototransistor 7. When light enters the phototransistor 7 from the detector 3 via the optical fiber 5 and the lens 6, a detection circuit 8 is provided.
, An overcharge or overdischarge detection signal is output. And
A stop signal is output from the detection circuit 8 to the AC / DC converter 9 provided in the charging / discharging circuit of the battery pack B, so that charging of the battery pack B or discharging from the battery pack is stopped, and a buzzer, a lamp or the like is used. An operation signal is output to the alarm device 10 to notify an overcharged or overdischarged state.

In this embodiment, a charge / discharge end monitoring device 11 is connected between both terminals of the battery pack B, and the charge / discharge end of the whole battery pack B is monitored by the charge / discharge end monitor device 11. It is supposed to be.

Therefore, in the overcharge / discharge monitoring device of this embodiment, the overcharge and overdischarge of the block 1b can be accurately monitored by the detectors 3 provided for each of the adjacent blocks 1b of the battery pack B. it can. In addition, the detector 3 has a simple and non-bulky configuration in which only a pair of light emitting diodes is provided, and only a small number of monitoring devices 4 need to be installed as shown in FIG. Therefore, the number of detectors 3 can be reduced by half, the cost can be reduced, and the device can be reduced in size and the installation space can be reduced, as compared with the conventional device in which a detector is provided for each block of the assembled battery. Can be reduced. In particular, when the present invention is applied to a large-scale battery system such as a power storage battery, it is possible to prevent the cost of the monitoring apparatus from significantly increasing and from requiring a large installation space.

The present invention is not limited to the configuration of the above embodiment, but may be embodied in the following manner, for example. (1) Instead of the light emitting diode of the above-described embodiment, an instrument for directly detecting a voltage difference, such as a voltmeter, is provided as the detector 3. (2) The charge / discharge end monitoring device 11 of the above embodiment is omitted. (3) As shown in FIG. 4, a circuit between each block 1b,
Detectors 3 are connected to both ends of the entire circuit between the resistors 2 and the series circuit of the resistors 2. (4) As shown in FIG. 5, a plurality of adjacent blocks 1b
As one block unit, and the resistor 2 is arranged for each block unit. That is, when a block unit is composed of two blocks 1b, one block 1b constitutes a unit with both adjacent blocks 1b. Therefore, a series circuit of the resistors 2 is formed in two rows. When one block unit is constituted by three blocks 1b, three series circuits of resistors 2 are formed. (5) The above-described embodiment and the configurations of the above-described other examples (1) to (4) are appropriately combined.

[0016]

Since the present invention is constructed as described above, the structure can be simplified and the cost can be reduced, and the apparatus can be downsized and the installation space can be reduced. It works.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing an embodiment of an overcharge / discharge monitoring device for an assembled battery embodying the present invention.

FIG. 2 is a circuit diagram showing one block in the assembled battery in detail.

FIG. 3 is a graph showing a relationship between a block voltage and a discharge depth.

FIG. 4 is a circuit diagram showing another example of the present invention.

FIG. 5 is a circuit diagram showing still another example of the present invention.

FIG. 6 is a circuit diagram showing a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... unit cell, 1b ... block, 2 ... voltage division resistance, 3 ... detector, B ... collective battery

Claims (1)

(57) [Claims] 1. An assembled battery comprising a block of unit cells as a basic unit and a predetermined number of such blocks connected in series, wherein a voltage dividing resistor is connected in parallel to one or a plurality of adjacent blocks. An overcharge / discharge monitoring apparatus for an assembled battery, wherein a detector for detecting voltage or current is connected between a circuit between resistors and a circuit between blocks.