JP2012129023A - Battery system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery system which, by detecting a sealed state of a battery container, can prevent a fault in the battery system or adverse effects on the user, etc. caused by an inability to maintain the sealed state.SOLUTION: The battery system includes a battery cell provided with a sealed battery container, a cap joined under pressure to the battery container to form a sealed space between it and the battery container and also provided in the sealed space with a gas conversion substance which converts first gas to second gas and a gas sensor which measures the quantity or concentration of the second gas, and a control unit which receives information corresponding to the quantity or concentration of the second gas. The control unit, if the information shows an increase in the quantity or concentration of the second gas, determines that airtightness of the battery container has broken.

Description

  The present invention relates to a battery system, and more particularly to a battery system that determines a sealed state of a battery cell.

A battery cell is stored in a battery container in which a positive electrode plate, a negative electrode plate, an electrolytic solution, and the like are sealed, and is commercially available as a product. However, battery containers that should be sealed at the time of manufacture may not be strictly sealed at the time of manufacture due to defects such as welding. Moreover, a hole may open in the sealed location of a battery container depending on the state and use environment where a battery cell is used after being marketed. That is, the sealed state of the battery container may not be maintained.
As described above, when the sealed state of the battery container cannot be maintained, the electrolytic solution that is a chemical or the chemical gas generated inside the battery cell when used is incorporated into the battery cell and receives power supply from the battery cell. There is a risk of causing a failure in the battery system as a result of, for example, contacting the component parts of the battery system and corroding the component parts.
In addition, the electrolyte and gas are generally toxic to the human body, and if the sealed state of the battery container cannot be maintained, the battery system user or the person performing maintenance work may be adversely affected. There is a fear.
Therefore, a structure for inspecting the gas leaked from the battery container in the factory by the gas sensor at the time of manufacturing the battery cell (see Patent Document 1), and a plurality of battery cells used in the battery system are connected after the market. In order to detect gas leaking from the assembled battery, a configuration in which a gas sensor is arranged in the container of the assembled battery (see Patent Document 2) has been reported.

Japanese Patent Laid-Open No. 9-259898 JP 2008-251307 A

However, the techniques of Patent Document 1 and Patent Document 2 can detect a gas generated in a battery container and leaking outside the battery container with a gas sensor. However, as long as the gas is floating, the gas However, it is not easy to avoid contact with components of the battery system or contact with a person who performs maintenance work in the factory. That is, it has been difficult to prevent the battery system from being damaged due to the corrosion and adversely affecting users.
Therefore, the present invention not only can detect whether or not the sealed state of the battery container can be maintained, but also has a negative effect on the user or the like due to the failure of the battery system caused by the failure to maintain the sealed state. An object of the present invention is to provide a battery system that can be prevented.

In order to achieve the above object, the battery system of the present invention forms a sealed space between a battery cell having a sealed battery container and the battery container by being crimped to the battery container, A cap having a gas converting substance for converting the first gas into the second gas and a gas sensor for measuring the amount or concentration of the second gas in the sealed space, and corresponding to the amount or concentration of the second gas A control device that receives the information to be performed, and the control device determines that the sealing of the battery container is broken when the information indicates an increase in the amount or concentration of the second gas. To do.

  That is, when the sealed state of the battery container cannot be maintained, the first gas generated from the inside of the battery container is converted into a predetermined second gas by the gas conversion substance, and the gas sensor determines the amount or concentration of the second gas. Since the measurement is performed, the control device not only can easily detect whether or not the sealed state of the battery container can be maintained, but also by converting to the predetermined second gas, It is possible to prevent the above adverse effects.

  According to the battery system of the present invention, it is possible not only to detect whether or not the sealed state of the battery container can be maintained, but also to a failure or a user of the battery system caused by the failure to maintain the sealed state. It is possible to provide a battery system that can prevent the adverse effects of the battery.

It is a battery system schematic diagram of an embodiment of the present invention. It is a schematic diagram which shows the physical connection relationship of the battery cell and gas detection cap in the battery system of embodiment of this invention.

  In the battery system according to the embodiment of the present invention, when a gas detection cap (described later) is fitted to the battery container of each battery cell and the sealed state of the battery container cannot be maintained (when the sealed battery container is broken), the battery system Gas that leaks from the inside of the container to the outside, such as toxic gas, is converted into non-toxic gas inside the gas detection cap, and the amount or concentration of the non-toxic gas is measured by a gas sensor arranged in the gas detection cap. One of the features is that the display device appropriately displays that the sealed state of the battery container can no longer be maintained. Hereinafter, it will be described in detail with reference to the drawings.

Hereinafter, a battery system according to an embodiment of the present invention will be described with reference to the drawings. First, the outline of the configuration of the battery system 1 will be described with reference to FIG. 1, and further, the configuration of the gas detection cap used in the battery system 1 will be described in detail with reference to FIG. 2, and then the battery system will be described with reference to FIGS. 1 describes how to detect whether the sealed state of the battery container can no longer be maintained (hereinafter referred to as “battery container breakage detection”).

FIG. 1 is a diagram showing a configuration of the battery system 1. The battery cell used in the battery system 1 can be any battery such as a primary battery or a secondary battery depending on the use of the battery system 1. Here, as an example of the battery cell, a chargeable / dischargeable battery It demonstrates using the battery cell of the cell, for example, the lithium ion secondary battery which is a storage battery.
The battery system 1 includes a battery module 2, a power load 3, a host control device 4, and a display device 5.
A battery module 2 including an assembled battery composed of a plurality of battery cells CEa to CEh and a BMS (Battery Management System) 6 that is a monitoring control device for the assembled battery is fitted from the outside of the battery system 1 to the inside of the battery system 1. Fixed. By using a module, the battery system 1 can be easily replaced from the outside. Note that the power load 3, the host control device 4, and the display device 5 are incorporated in the battery system 1 in advance. Here, the host control device 4 and the BMS 6 may be simply referred to as a control device.
Here, the battery system 1 includes, for example, an industrial vehicle such as a forklift that has wheels connected to an electric motor that is an electric load 3, a moving body such as a train or an electric vehicle, and an electric motor that is an electric load 3 with a propeller or a screw. It may be a moving body such as an airplane or a ship connected to each other. Furthermore, the battery system 1 may be a stationary system such as a home power storage system or a grid-connected smoothing power storage system combined with a natural energy power generation such as a windmill or sunlight. That is, the battery system 1 is a system that uses at least discharge of electric power from a plurality of battery cells that constitute an assembled battery, and may be a system that uses charge and discharge.

The assembled battery in the battery module 2 supplies power to the power load 3 of the battery system 1, from the battery cells CEe to CEh connected in series with the first arm composed of the battery cells CEa to CEd connected in series. Are connected in parallel. In addition, hereinafter, for each configuration of the voltage sensor V, temperature sensor T, gas sensor G and the like corresponding to each of the battery cells CEa to CEh, a to h are appropriately described at the end of the explanation symbol of each corresponding configuration. Whether or not it is an explanation of the configuration corresponding to the battery cell.
The plurality of battery cells CEa to CEh constituting the assembled battery include one temperature sensor Ta to Th for measuring the cell temperature and one voltage sensor Va to Vh for measuring the cell voltage for each battery cell. They are arranged corresponding to each other. Moreover, in order to detect the gas which leaks from the battery container of each battery cell in each of these battery cells, gas sensor Ga-Gh is arrange | positioned corresponding to each battery cell, respectively.
Furthermore, each arm has one corresponding current sensor, here a current sensor Iα is arranged for the first arm, and a current sensor Iβ is arranged for the second arm. It can be measured.
Detection / measurement information output by various sensors that detect and measure the cell temperature, cell voltage, current flowing through each arm, and the presence or absence of gas leakage described above is input to the BMS 6 described later.
Here, four battery cells are connected in series to form one arm, and a total of two arms are connected in parallel. However, the number of battery cells connected to each arm and the number of arms can be designed to be one or more.

The BMS 6 includes two CMUs (Cell Monitor Units), that is, CMU1 and CMU2, and a BMU (Battery Management Unit).
Here, the CMU 1 and the CMU 2 include an ADC (Analog Digital Converter) (not shown), and each of the plurality of detection / measurement information detected and output by the various sensors is received as an analog signal. After converting into a digital signal corresponding to each, the related information (information related to the detection / measurement information, including the charging rate (SOC) of each battery cell calculated by the BMU. Also, each battery cell. Are output to the BMU as a plurality of parameters for calculating and the like. In this embodiment, as shown in FIG. 1, each CMU is connected to each of the various sensors corresponding to four battery cells by buses or signal lines.

The host controller 4 controls the power load 3 according to a user instruction (for example, when the battery system 1 is an electric vehicle, the amount of depression of the accelerator pedal by the user), and the battery pack transmitted from the BMS 6 The related information is received, the display device 5 is controlled, and the related information is appropriately displayed on the display device 5. When the host control device 4 determines that the related information is an abnormal value, it turns on an abnormal lamp built in the display device 5 and sounds such as a buzzer built in the display device 5. Operate the device to sound an alarm and stimulate the user's attention by stimulating vision and hearing with light and sound.
The display device 5 is a monitor such as a liquid crystal panel provided with the acoustic device, for example, and displays the related information of each of the plurality of battery cells CEa to CEh constituting the assembled battery based on control from the host control device 4. It can be performed.
The power load 3 is a power converter such as an electric motor or an inverter connected to the wheels of the electric vehicle, for example. The electric power load 3 may be an electric motor that drives a wiper or the like.

The physical connection relationship between the battery cells CEa to CEh and the gas detection caps CAa to CAh used in the battery system 1 will be described with reference to FIG. Since all the battery cells CE and the gas detection cap CA have the same configuration and the same physical connection relationship, the battery cell CEa and the gas detection cap CAa will be representatively described here. .
2A to 2E all use the same orthogonal coordinate system. In addition, the dimensions L1 to L7, W1 to W3, and D1 to D3 shown below are as follows: 0 <L7 <L3 ≦ L5 <L4 <L6 <L1 ≦ L2, 0 <W2 ≦ W1 <W3, 0 <D2 ≦ D1 <D3.

Fig.2 (a) is a figure which shows the structure outline | summary of the battery cell CEa. The battery container of the battery cell CEa has a rectangular shape, and the container 7 in which a laminated electrode body (not shown) is housed is sealed with a lid 8 to constitute the battery cell CEa. The battery container includes a container 7 and a lid 8.
The container 7 has a substantially rectangular bottom surface with a short side (dimension D1) in the Y-axis direction and a long side (dimension W1) in the X-axis direction, and is connected to all the sides of the bottom surface in a direction perpendicular to the bottom surface. It is a container having a wall surface extending in the (+ Z direction).
The lid 8 has a plate shape that is substantially the same as the bottom surface of the battery case 2, and the electrode terminals (the positive electrode terminal 9 or the negative electrode terminal 10) penetrate and are fixed to both sides of the plate shape. . Although not shown, the lid 8 is also formed with a liquid injection hole for injecting an electrolytic solution. Here, a cylindrical electrode terminal having a substantially circular shape with a radius r on the XY plane is used.
The container 7 and the lid 8 may be made of an insulating plastic resin that is not altered by an electrolytic solution or the like, or may be made of a conductive metal such as aluminum. If these are made of the same material, the container 7 and the lid 8 can be effectively sealed by welding, adhesion, heat welding, or the like. Here, since these are conductive cases, an insulating member 11 such as a plastic resin is provided between the electrode terminal and the lid 8 so that the electrode terminal is not electrically connected to the lid 8.
In addition, since the injection hole is not filled in the sealing stage, in a strict sense, it is not a substantially complete sealed state. After the sealing, an electrolyte solution (not shown) is injected from the injection hole, and the injection hole is closed with a sealing member such as a screw to obtain a substantially complete sealed state. In order to make the substantially complete sealed state more complete, the sealing member is preferably made of the same material as the lid 8.

The laminated electrode body may be a laminated electrode body (laminated laminated electrode body) in which a plurality of positive electrode plates and a plurality of negative electrode plates are sequentially laminated via separators, or one positive electrode plate and one negative electrode plate. May be a laminated electrode body (rolled laminated electrode body) in a state of being laminated and wound via one separator.
Although not shown, the laminated electrode body is coated with a positive electrode tab (which is coated with a positive electrode active material such as lithium manganate) and a negative electrode plate (which is coated with a negative electrode active material such as carbon). And a negative electrode tab extending from the positive electrode terminal 9 and the negative electrode terminal 10 corresponding to the positive electrode terminal 9 and the negative electrode terminal 10 respectively.

Next, the configuration of the gas detection cap CA will be described with reference to FIGS.
In order to facilitate understanding of the positional relationship between the components shown in FIGS. 2B to 2D, alternate long and short dash lines are appropriately described between these drawings.
The gas detection cap CA is a portion where a poor connection or breakage is likely to occur, such as “a joint where the container 7 and the lid 8 are welded, bonded, or thermally welded” or “the electrode terminal and the lid 8 are joined with a resin or the like. A space between the battery cell and the inside of the gas detection cap CA that covers and seals a portion (hereinafter referred to as a gas leakage risk portion) with a probability that the sealed state of the battery container such as the “joint” cannot be maintained. The gas flow path is formed so that the gas leaking from the gas leakage risk site can be guided to the gas sensor arranged inside the gas detection cap CA.
Specifically, the gas detection cap CA is made of an elastic resin such as rubber, and the outer shape is a substantially rectangular flat plate portion 12 having a dimension W3 in the X direction and a dimension D3 in the Y direction (in the Z direction). The thickness is (L4-L5)) and is connected to the four sides of the flat plate portion 12 and extends in the −Z direction from the four sides (the container 7 is pressed with substantially no gap and is in close contact with the container 7) Is referred to herein as “crimping”, and the crimping portion 13 can perform this crimping), and on the −Z side surface (the back surface of the flat plate portion 12) of the two surfaces existing on the XY plane of the flat plate portion 12. The support column 15 connected and extending in the −Z direction from the back surface (when the gas detection cap CA is attached to the battery cell, the space is formed by supporting the flat plate portion 12 interposed between the flat plate portion 12 and the lid 8. Forming).
Of the two surfaces existing on the XY plane of the flat plate portion 12, the + Z side surface is hereinafter referred to as the surface of the flat plate portion 12.
A circuit board 17 to be described later may be fixed to the surface of the flat plate portion 12 and the gas detection cap CA including the circuit board 17 may be used.
Hereinafter, each configuration of the gas detection cap CA will be described in detail.

FIG. 2E shows the gas detection cap CA as viewed from the −Z side, that is, a rear view of the gas detection cap CA.
The flat plate portion 12 is formed with a through-hole 14 at a position corresponding to the electrode terminal, which is substantially the same and slightly smaller than the cross-sectional shape of the electrode terminal in the XY plane and penetrates the flat plate portion 12 in the Z direction. ing. Here, since the cross-sectional shape of the electrode terminal is a substantially circle having a diameter (2 × r), the shape of the through hole 14 is also a shape of the substantially circle. The reason why the shape is slightly smaller as described above is to press the flat plate portion 12 into close contact with the electrode terminal and to prevent a gap from being substantially formed between the electrode terminal and the flat plate portion 12. is there.
The “crimping” is a term including that the flat plate portion 12 presses the electrode terminal substantially without any gap and adheres to the electrode terminal. Therefore, it can be said that the flat plate portion 12 is crimped to the electrode terminal.

The crimping portion 13 is in contact with and surrounds the entire circumference of the flat plate 12 as viewed in the XY plane. Specifically, on the back surface of the substantially rectangular flat plate portion 12 having the dimension W3 × D3, the thickness {(W3) from the two sides of the substantially rectangular shape in the Y direction toward the inside of the flat plate portion 12 in the X axis direction, respectively. -W1) / 2} and the height in the Z direction is a dimension L2 from the surface of the flat plate portion 12, and the first region 13a is in contact with the first region 13a on the back surface of the flat plate portion 12 and is in the X-axis direction. And a second region 13b having a thickness {(W1-W2) / 2} and a height in the Z direction being a dimension L3 from the surface of the flat plate portion 12, and the substantially rectangular shape in the X direction. The thickness from the two sides to the inside of the flat plate portion 12 in the Y-axis direction is a width {(D3-D1) / 2}, and the height in the Z direction is a dimension L2 from the surface of the flat plate portion 12. It is arranged on the back surface of the flat plate portion 12 in contact with the region 13c and the third region 13c, and each is in the Y-axis direction. The pressure-bonding portion 13 has a fourth region 13d having a width {(D1−D2) / 2} and a height in the Z direction that is a dimension L3 from the surface of the flat plate portion 12 in the direction toward the inside of the flat plate portion 12. I have.
The two first regions 13a and the two third regions 13c are connected to each other, and as shown in FIG. 2 (e), when viewed from the back surface of the flat plate portion 12, they form a square shape. This square shape is a part that is directly crimped to the battery cell CE (hereinafter referred to as a direct crimping part).
Also, the two second regions 13b and the two fourth regions 13d are connected to each other, and as shown in FIG. 2 (e), when viewed from the back surface of the flat plate portion 12, they form a square shape. This square shape does not come into contact with the battery cell CE by the support column 15 to be described later, but is formed by connecting to the flat plate portion 12 and the direct crimping portion, thereby providing a pressure bonding strength at the direct crimping portion. It becomes a part (henceforth a crimping | compression-bonding reinforcement part) which can increase this.
In addition, a groove (hereinafter referred to as a first groove) is formed in the vicinity of the direct crimping portion in the vicinity of the “joint where the container 7 and the lid 8 are welded, bonded, or thermally welded”, which is a gas leakage risk portion. In this first groove, a gas conversion material 16 (described later) is disposed so as to be applied. In addition, a groove (hereinafter referred to as a second groove) is formed in the vicinity of the “bonding portion in which the electrode terminal and the lid 8 are bonded with a resin or the like”, which is a gas leakage risk portion, in the crimping reinforcement portion. In the second groove, a gas conversion material 16 to be described later is disposed, for example. In FIG.2 (e), the area | region where the gas conversion substance 16 is arrange | positioned is shown with the wavy line, and the gas conversion substance 16 is substantially entirely surrounded by the direct crimping | compression-bonding site | part and a crimping | compression-bonding reinforcement site | part so that a gas leak risk site | part may be surrounded. Is placed.

  The column portion 15 is connected to the back surface of the flat plate portion 12 and has a columnar configuration extending by a dimension L5 in the −Z direction from the back surface. When the gas detection cap CA is inserted and fitted into the battery cell CE, and the battery cell CE is pressure-bonded with the gas detection cap CA, the support column 15 is a flat plate so that the support column 15 can directly contact the battery cell CE. 12 are appropriately arranged on the back surface. In FIG. 2 (e), four support columns 15 are formed so as to surround a gas sensor G described later in contact with the pressure-bonding reinforcement portion. However, the thickness and shape of the support column 15 are appropriately designed so as not to hinder the formation of the gas flow path that can guide the gas leaking from the gas leakage risk site to the gas sensor G by the support column 15. .

The gas sensor G (the gas sensor Ga in FIG. 2) has a dimension in the Z direction of L7, and here, the shape of the XY plane is a cylindrical shape having a diameter smaller than the dimension D2. Furthermore, here, when the gas detection cap CA is inserted into the battery cell CE and fitted together, a safety valve formed on the lid 8 (not shown. The safety valve is generally thinner than the lid 8 and has a risk of gas leakage. It is arranged and fixed on the back surface of the flat plate portion 12 so as to be positioned in the + Z direction.
Any kind of gas sensor G may be used as appropriate according to the type of gas generated in the battery cell CE or the type of gas conversion substance described below. Details will be described later.

With the above-described configuration of the gas detection cap CA, when the gas detection cap CA is inserted and fitted into the battery cell CE and the battery cell CE is pressure-bonded with the gas detection cap CA, the gas detection cap CA is interposed between the battery cell CE and the gas detection cap CA. A small room, that is, a sealed space (hereinafter referred to as a sealed space) can be formed. Then, when the gas generated inside the battery cell CE leaks from the gas leakage risk site, a gas flow path capable of guiding the gas to the gas sensor G arranged in the sealed space is formed in the sealed space. The
Note that the flat plate portion 12, the crimping portion 13, and the support column portion 15 of the gas detection cap CA may be integrally formed of the same material by using molding.

By the way, as described above, the circuit board 16 may be fixed to the surface of the flat plate portion 12 to form the gas detection cap CA.
Here, the circuit board 16 is a plastic substrate having a weaker elastic force than the flat plate portion 12. The circuit board 16 has a shape that is substantially the same as the cross-sectional shape of the XY plane of the electrode terminal at a position corresponding to the through hole 14 of the flat plate portion 12 and is slightly larger. A penetrating through hole (hereinafter referred to as a circuit board through hole) is formed. Here, since the cross-sectional shape of the electrode terminal is a substantially circular shape, the shape of the through hole 14 is also a substantially circular shape.
On the circuit board 16, temperature sensors Ta to Th corresponding to the battery cells CEa to CEh shown in FIG. 1 and voltage sensors Va to Vh for measuring cell voltages are arranged and fixed. The circuit board 16 is connected to a printed wiring that transmits the measured values of the temperature sensor and the voltage sensor, and a printed wiring that is connected to an electrical path that penetrates the flat plate portion 12 for transmitting the measured values of the gas sensor G. Are appropriately formed. Further, when the gas detection cap CA is inserted into the battery cell CE and fitted in the battery cell CE in order to appropriately supply operating power to these sensors and measure the cell voltage, the battery is inserted through the through hole for the circuit board. Printed wiring and terminals that are automatically electrically connected to the positive terminal 9 and the negative terminal 10 of the cell CE are also formed on the circuit board 16.
Although not shown, the circuit board 16 is appropriately connected to a bus or a signal line that electrically connects the printed wiring and the BMS 6.
By using the gas detection cap CA including the circuit board 16 as described above, when the gas detection cap CA is inserted into the battery cell CE and fitted and crimped, various sensors corresponding to the battery cell are simultaneously connected with one touch. Therefore, the battery system 1 can be easily and easily manufactured and repaired, and the manufacturing cost and repair cost can be reduced.

Note that the bus bar, which is a wiring that electrically connects the battery cells CEa to CEh constituting each arm in series connection or the like, passes through the circuit board through hole of the circuit board 16 arranged in each battery cell, and the circuit board 16. It is connected to the protruding portion of the electrode terminal protruding in the + Z direction. Thereby, the battery system 1 of FIG. 1 is comprised.

Now, “battery container breakage detection” by the battery system 1 will be described with reference to FIGS. 1 and 2.
In this embodiment, since a lithium ion secondary battery is mentioned as an example of the battery cell CE, the battery container hermetic breakage detection of each battery cell CE is performed by detecting the gas generated from the battery container of the lithium ion secondary battery. .
By charging or discharging a lithium ion secondary battery, not only carbon dioxide (CO ₂ ), which is harmless to the human body, but also hydrogen fluoride (HF), carbon monoxide (CO), etc., which are toxic gases to the human body, are battery containers. Occurs inside. This hydrogen fluoride (HF) is also a gas that causes the corrosion.
Therefore, here, a description will be given assuming that the battery container hermetic breakage is detected by converting typically harmful hydrogen fluoride gas into harmless gas and measuring the amount of the harmless gas.
For this reason, sodium carbonate (Na ₂ CO ₃ ) that converts hydrogen fluoride gas, which is a harmful gas, into carbon dioxide gas, which is a harmless gas, is disposed in the gas detection cap CA as a gas conversion substance 16. As the gas sensor G, a carbon dioxide gas sensor that detects carbon dioxide (for example, TGS4161 manufactured by Figaro Giken Co., Ltd.) is used. Sodium carbonate (Na ₂ CO ₃ ) can also function as a fire extinguishing agent when the battery cell ignites, so it is very useful in terms of improving the safety of the battery system 1.
In addition, the conversion from hydrogen fluoride gas to carbon dioxide gas is performed by bringing the hydrogen fluoride gas into contact with sodium carbonate as the gas conversion material 16, and thus the chemistry of “Na ₂ CO ₃ + HF → NaF ₂ + H ₂ O + CO ₂ ”. This is achieved when a reaction occurs.

First, the battery system 1 is configured by appropriately connecting the gas detection cap CA to the battery cells CEa to CEh as shown in FIG. 2 and then electrically connecting the components of the battery system 1 as shown in FIG. Has been. Here, the BMS 6 includes a non-volatile memory (not shown), and the gas amount or gas concentration of a predetermined gas (in this case, carbon dioxide gas) in the sealed space when the sealed state of the battery container can be maintained. (Gas reference value) is stored in advance in the non-volatile memory (for example, stored in a factory or the like before being commercially available).
Next, when the battery system 1 constructed on the market or under the user is started and the operation of the battery system 1 is started, the BMS 6 is configured to supply each gas at a predetermined timing (for example, every 5 minutes). Detection / measurement information relating to the gas amount or gas concentration value of a predetermined gas (here, carbon dioxide gas) measured by the sensors Ga to Gh is used as the gas reference value (measurement unit corresponding to the detection / measurement information, for example, voltage, etc. Is the unit value). As a result of comparison, when the value indicated by the detection / measurement information increases by a predetermined amount or a predetermined concentration (for example, 1000 ppm) from the gas reference value, the BMS 6 indicates a battery cell that indicates the increased value. It is determined that the sealing of the battery container is broken. Therefore, the battery container hermetic breakage detection information corresponding to the battery cell is activated and transmitted to the host control device 4 as one of the related information.

At this time, in the battery cell showing the increased value, the gas generated inside the battery cell leaks from the gas leakage risk part. That is, in the battery cell, the sealing of the battery container is broken. Accordingly, carbon dioxide gas, which is part of the gas generated inside the battery cell, spreads as it is in the sealed space and is directly measured by the gas sensor G, which is a carbon dioxide gas sensor, and is generated inside the battery cell. The harmful hydrogen fluoride gas, which is another part of the generated gas, is converted into harmless carbon dioxide gas by contacting the gas conversion substance 16 when spreading into the sealed space, and indirectly by the gas sensor G. It is measured. For this reason, not only the carbon dioxide gas directly measured by the gas sensor G but also the amount or concentration of the hydrogen fluoride gas indirectly measured by the gas sensor G is added, so that the gas conversion substance Compared with the case where 16 is not arranged, the value indicated by the detection / measurement information becomes larger at an early stage.

And the high-order control apparatus 4 which received the said relevant information from BMS6 displays on the display apparatus 5 which battery cell CEa-CEh the battery cell in which battery container sealing destruction detection information became active, and said It is determined that the value is an abnormal value, and the display device 5 is controlled as described above to alert the user.
Further, the host control device 4 controls the display device 5 to prompt the user's attention as described above, and the current from each arm supplied to the power load 3 after a predetermined time has elapsed (for example, after 5 minutes). A warning to the effect of restriction regardless of the user's intention is also displayed on the display device 5. Then, after the predetermined time has elapsed, the host control device 4 uses the related information from the temperature sensor corresponding to the battery cell in which the battery container sealing failure detection information is active, and the measured value of the temperature sensor is set to the predetermined temperature. The upper limit value of the current supplied to the power load 3 or the power supplied to the power load 3 is limited so as to be below (for example, 40 ° C. or lower). When the sealing of the battery container is broken, it may be in a dangerous state where the temperature of the battery cell rises and the battery container expands, and the power load is required to cool quickly below the predetermined temperature. The upper limit of the electric current supplied to the electric power 3 or the electric power supplied to the electric power load 3 is limited.
Therefore, the user is strongly motivated to check and repair the battery system 1 and further the upper limit value of the current to the electric power load 3 is restricted, so that the battery system 1 can be operated safely. That is, the safety of the battery system 1 can be improved.

In the above description, the BMS 6 performs the comparison using the gas reference value stored in the nonvolatile memory (not shown), but there may be a case where the gas reference value of the nonvolatile memory is not used.
In this case, for example, a gas sensor (having the same configuration as the gas sensor G) is arranged in the casing of the battery module 2 in order to obtain a reference value from the outside air of the battery system 1, and information measured by the gas sensor is stored in the BMS 6 May be configured to receive. That is, in this configuration, the gas reference value is not a fixed value but a variable value according to the use environment of the battery system 1 and is compared with the values measured by the gas sensors Ga to Gh.
That is, in the case of the variable value, the BMS 6 is a gas of a predetermined gas (in this case, carbon dioxide gas) measured by each gas sensor Ga to Gh at a predetermined timing (for example, every 5 minutes). Gas amount or gas concentration of a predetermined gas (in this case, carbon dioxide gas) measured by the same gas sensor as the gas sensor G installed in the casing of the battery module 2 as detection / measurement information relating to the amount or gas concentration value Compared with detection / measurement information on the value of (gas reference value). As a result of comparison, when the value indicated by the detection / measurement information corresponding to each gas sensor Ga to Gh increases by a predetermined amount or a predetermined concentration (for example, 1000 ppm) from the gas reference value, the BMS 6 It is determined that the sealing of the battery container of the battery cell showing the obtained value has been broken. Therefore, the battery container hermetic breakage detection information corresponding to the battery cell is activated and transmitted to the host control device 4 as one of the related information. Subsequent operations are the same as those described above.

In the above description, the hydrogen fluoride gas, which is a harmful gas, is focused. However, the carbon monoxide gas, which is a harmful gas, may be focused. In this case, the gas conversion substance 16 is changed to, for example, a substance that converts harmful carbon monoxide gas into harmless carbon dioxide gas (for example, RTC-B2 manufactured by Caterer Co., Ltd. as a carbon monoxide oxidation catalyst). Even if it changes in this way, a battery container sealing destruction detection can be performed by the operation | movement similar to the above.
Of course, the gas conversion substance 16 is not limited to one kind, and two or more kinds of substances may be arranged in the gas detection cap CA. For example, if sodium carbonate and a carbon monoxide oxidation catalyst are disposed in the gas detection cap CA as the gas conversion substance 16, both toxic hydrogen fluoride gas and carbon monoxide gas can be rendered harmless, and these gases are harmless. By converting to carbon dioxide and increasing the amount or concentration of carbon dioxide gas in the sealed space earlier, the battery container hermetic breakage detection information is activated earlier than when the gas converting substance 16 is not disposed. Can do. Therefore, the safety of the battery system 1 can be further improved.
When the battery cell is a battery other than a lithium ion secondary battery, the above battery can be selected by appropriately selecting the types of the gas conversion substance 16 and the gas sensor G according to the gas generated inside the battery. The same operation as the container hermetic breakage detection can be performed.

The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. For example, in the above embodiment, the BMS 6 of the battery module 2 and the host control device 4 are separately discussed, but these may be controlled as one control device.
The shape of the battery container has been described as a square shape, but may be a cylindrical shape.
Furthermore, since the electrode terminal has a cylindrical shape, the shape of the through hole 14 and the through hole for the circuit board is also a substantially circular shape corresponding thereto, but is not limited thereto. The shape of the electrode terminal can be changed as appropriate, such as a triangular prism or a quadrangular prism. In this case, the shape of the through hole 14 or the through hole for the circuit board can also be changed as appropriate according to the shape of the electrode terminal.

DESCRIPTION OF SYMBOLS 1 ... Battery system, 2 ... Battery module, 3 ... Electric power load, 4 ... High-order control apparatus,
DESCRIPTION OF SYMBOLS 5 ... Display apparatus, 6 ... BMS, 7 ... Container, 8 ... Cover, 9 ... Positive electrode terminal, 10 ... Negative electrode terminal,
DESCRIPTION OF SYMBOLS 11 ... Insulating resin, 12 ... Flat plate part, 13 ... Crimp part, 14 ... Through-hole, 15 ... Support | pillar part,
16 ... gas conversion substance, 17 ... circuit board,

Claims (6)

A battery cell with a sealed battery container;
A gas that forms a sealed space between the battery container and the gas conversion substance that converts the first gas into the second gas, and a gas that measures the amount or concentration of the second gas. A cap provided with a sensor in the sealed space;
A control device for receiving information corresponding to the amount or concentration of the second gas,
The control device determines that the sealing of the battery container is broken when the information indicates an increase in the amount or concentration of the second gas. The battery system according to claim 1, wherein the first gas is a toxic gas and the second gas is a harmless gas. The battery system according to claim 2, wherein the first gas is hydrogen fluoride gas and the second gas is carbon dioxide gas. The battery system according to claim 2, wherein the first gas is carbon monoxide gas and the second gas is carbon dioxide gas. Further comprising a power load that operates by receiving power supply from the battery cell;
5. The battery system according to claim 3, wherein the control device limits an upper limit value of the power supply when it is determined that the sealing of the battery container is broken. Further comprising an acoustic device;
6. The battery system according to claim 5, wherein, when it is determined that the sealing of the battery container is broken, the control device operates the sound device to sound an alarm.

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