KR102390992B1 - A system of leaking inspection of toxic substance and leaking inspection method of toxic substance using thereof - Google Patents

Abstract

A secondary battery electrolyte leakage inspection system according to the present invention accommodates an object to be detected (pouch cell) and a sensor in a vacuum chamber and a sensor chamber, which are a kind of closed system, respectively, changes fluid pressure inside the vacuum chamber and the sensor chamber to quickly detect the leakage of harmful components and quickly detect the generation of toxic gases such as carbon monoxide and acetylene, thereby preventing the occurrence of a fire in advance, and more accurately and easily detecting whether a defect has occurred in an exterior material of the object to be detected (pouch cell), in particular, a battery cell.

Description

BACKGROUND OF THE INVENTION Field of the Invention [0002] A system of leak inspection of secondary battery electrolyte and a leak inspection method of electrolyte using the same

The present invention relates to a leak test system for a secondary battery and a leak test method for an electrolyte using the same, and more particularly, to rapidly detect the leak of harmful components in a battery such as a battery to be detected (a pouch cell), in particular, electrolyte potassium hydroxide, It relates to a secondary battery electrolyte leakage inspection system capable of suppressing the generation of toxic gases such as acetylene and preventing the occurrence of fire in advance, and an electrolyte leakage inspection method using the same.

Recently, with the rapid spread of electric vehicles, laptops, and mobile communication devices, the need for a light-weight and large-capacity power supply means that can be recharged is increasing.

According to this trend, nickel-hydrogen (Ni-MH) batteries, lithium (Li) batteries, and lithium-ion (Li-ion) batteries, which charge and discharge power by ionizing the electrolyte and generating electromotive force between electrodes, are being used. Most of the batteries are called secondary batteries.

In general, secondary batteries are rechargeable, small and large-capacity, and they are divided into cylindrical batteries, prismatic batteries, and pouch batteries. ) The positive and negative terminals are side by side at the top of the battery, and the lead plate with a safety vent and electrolyte injection hole formed on the top of the case is sealed, and the electrolyte is injected through the electrolyte injection hole and then sealed.

The secondary battery manufactured in this way is operated in such a way that ions are generated from the electrolyte injected between the positive electrode and the negative electrode and move between the electrodes, thereby generating an electromotive force, and charging and discharging by the action.

Accordingly, the secondary battery has a closed type structure capable of preventing the loss of the electrolyte affecting the charge/discharge capacity and preventing leakage of the electrolyte in consideration of the generation of internal pressure.

In these secondary batteries, if the electrolyte leaks due to poor sealing of the case, it is treated as a product defect, so a leak test is performed in the manufacturing process line. Inspection is carried out by visual inspection.

However, in the case of X-ray inspection, since the process and facilities are complicated, the realization is low, and the visual inspection has a problem of low reliability. A method of inspecting a leak in a secondary battery by injecting nitrogen (N ₂ ) gas and checking whether He gas or N ₂ gas is detected with a He gas or N ₂ gas detection sensor is presented.

However, this method has disadvantages in terms of economics because the gas or sensor used is expensive, and the reliability is still low when applied to the actual field because the airtight test is performed in a state in which the electrolyte is not injected.

Republic of Korea Patent Publication No. 10-2001-0011231 (February 05, 2001)

The present invention has been devised to solve the above problems, and specifically, by rapidly detecting the leakage of electrolyte from a battery such as a detected object (pouch cell), especially secondary battery electrolyte, generation of toxic gases such as carbon monoxide and acetylene The purpose of the present invention is to provide an electrolyte leakage inspection system that can suppress the occurrence of fires and prevent the occurrence of fires, and a leak inspection method for hazardous substances using the same.

The present invention relates to an electrolyte leakage inspection system and a method for inspecting leakage of harmful substances using the same.

One aspect of the present invention is

A vacuum chamber including an upper housing and a lower housing that provides a space for accommodating an object (pouch cell) inside through coupling, and can shield the space for accommodating the object (pouch cell) from the outside ;

a sensor chamber accommodating the sensor therein; and

a connection unit sequentially connecting the vacuum chamber, the sensor chamber, and the vacuum pump;

It relates to an electrolyte leakage test system comprising a.

In the present invention, the sensor measures any one or a plurality of measurement targets selected from the total volatile organic compound content, the electrolytic component content, the carbon dioxide content, humidity and temperature of the fluid, and more specifically, the total volatile organic compound content of the fluid. The gas sensor that measures

Board;

a heating layer positioned on the substrate;

an electrode positioned on the heating layer but provided to cover a portion of the top portion of the heating layer and having a through-hole formed in the center thereof; and

a sensing unit provided to cover a portion of the electrode and the heating layer and including a metal oxide;

It is characterized in that it includes.

In addition, the connection part includes a connection pipe connecting the vacuum chamber and the sensor chamber, the sensor chamber and the vacuum pump, respectively,

The connection pipe further includes a throttle valve that can be opened and closed to control the flow of fluid in the vacuum chamber or the sensor chamber,

The leak inspection system of the hazardous substance,

an opening and closing unit for automatically opening and closing the upper housing; and

a vacuum chuck for inserting or removing an object (pouch cell) to be detected inside the lower housing after the upper housing is opened;

It is characterized in that it further comprises.

In addition, the electrolyte leak inspection system,

It is connected to the sensor to check any one or a plurality of information selected from total volatile organic compound content, electrolyte content, carbon dioxide content, humidity and temperature of the fluid, and select from vacuum pump, throttle valve, opening/closing part and vacuum chuck It may further include a control unit for controlling driving any one or all of the

The electrolyte leakage test system may be provided with a plurality of pairs of a vacuum chamber and a sensor chamber as a pair.

Another aspect of the present invention is a leak inspection method of harmful substances using the secondary battery electrolyte leakage inspection system according to the above, the inspection method comprising:

a) opening the opening/closing door of the vacuum chamber and accommodating the detection target (pouch cell) in the lower housing;

b) closing the upper housing and opening a connection part;

c) moving the fluid in the vacuum chamber to the sensor chamber by suctioning the vacuum pump with vacuum pressure;

d) measuring any one or a plurality of measurement objects selected from total volatile organic compound content, electrolyte content, carbon dioxide content, humidity and temperature in the fluid sucked through the sensor in the sensor chamber;

e) stopping the operation of the vacuum pump and closing the connection part; and

f) analyzing the measurement target measured by the sensor to determine whether the electrolyte leaks in the object to be detected (pouch cell);

It is characterized in that it includes.

In the present invention, the inspection method is after step f),

g) classifying the to-be-detected object (pouch cell) from which electrolyte is leaked by generating a signal in the vacuum chamber accommodating the detected object (pouch cell) when the electrolyte is detected in the object (pouch cell);

It may further include, if necessary, the inspection method after step g),

h) opening the upper housing of the vacuum chamber in which the detected object (pouch cell) from which the electrolyte is leaked is accommodated, and discharging the vacuum pump to discharge the fluid to the outside of the vacuum chamber and the sensor chamber.

The secondary battery electrolyte leakage inspection system according to the present invention accommodates a detection object (pouch cell) and a sensor in a vacuum chamber and a sensor chamber, which are a kind of closed system, respectively, and detects electrolyte leakage by changing the fluid pressure inside the vacuum chamber and the sensor chamber By quickly detecting the generation of toxic gases such as carbon monoxide and acetylene, it is possible to block the occurrence of fire in advance, and it is more accurate and easy to determine whether defects have occurred in the object to be detected (pouch cell), especially the exterior material of the secondary battery. can be captured

1 is a flowchart of an electrolyte leakage inspection method using a secondary battery electrolyte leakage inspection system according to the present invention.
2 is a diagram illustrating a process of receiving and removing a detection target (a pouch cell) in a vacuum chamber in the secondary battery electrolyte leakage inspection system according to the present invention.
3 shows a cross-section of a gas sensor according to the present invention.
4 is a diagram illustrating an example of a secondary battery electrolyte leakage inspection system according to the present invention.

Hereinafter, the secondary battery electrolyte leakage inspection system and the secondary battery electrolyte leakage inspection method using the same according to the present invention will be described in more detail by way of Examples and Comparative Examples. However, the embodiments introduced below are provided as examples so that the spirit of the present invention can be sufficiently conveyed to those skilled in the art.

Therefore, the present invention is not limited to the embodiments presented below and may be embodied in other forms, and the embodiments presented below are only described to clarify the spirit of the present invention, and the present invention is not limited thereto.

At this time, unless there are other definitions in the technical terms and scientific terms used, it has a meaning commonly understood by a person of ordinary skill in the art to which this invention belongs, and in the following description, it may unnecessarily obscure the subject matter of the present invention. A description of possible known functions and configurations will be omitted.

Also, the singular forms used in the specification and appended claims may also be intended to include the plural forms unless the context specifically dictates otherwise.

In addition, the drawings introduced below are provided as examples so that the spirit of the present invention can be sufficiently conveyed to those skilled in the art. Therefore, the present invention is not limited to the drawings presented below and may be embodied in other forms, and the drawings presented below may be exaggerated to clarify the spirit of the present invention. Also, like reference numerals refer to like elements throughout.

Also, the singular forms used in the specification and appended claims may also be intended to include the plural forms unless the context specifically dictates otherwise.

In describing the components of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only for distinguishing the elements from other elements, and the essence, order, or order of the elements are not limited by the terms. When it is described that a component is “connected”, “coupled” or “connected” to another component, the component may be directly connected or connected to the other component, but another component is formed between each component. It should be understood that elements may also be “connected,” “coupled,” or “connected.”

The secondary battery electrolyte leakage inspection system may target a detection target (pouch cell), in particular, a battery (B) that may leak due to damage. In this case, the battery includes an electrode, an electrolyte (liquid), an active material, and a casing material, and by the damage of the casing material, for example, substances such as potassium hydroxide or other carbon dioxide, sulfide, nitride, etc. are detected and their chemical Or it is characterized in that it suppresses the occurrence of a fire according to a physical reaction.

In addition, the secondary battery electrolyte is a generic term for leakage of components that should not occur through chemical or physical reactions due to damage to the object (pouch cell) to be detected, etc. In particular, as described above, when the secondary battery leaks It may include a metal oxide or metal hydroxide such as cobalt, nickel, manganese, and potassium.

If the battery, which is an example of the detected object (pouch cell), will be described in detail, since most of the battery's exterior material is formed of a pouch processed with a multi-layered polymer film, flexibility may be secured, but damage to the exterior may occur. there is. In particular, damage such as scratches or tears may occur in the process of forming an exterior material such as drawing or packaging an assembly such as an electrode or electrolyte using the exterior material. When the exterior material is damaged, external impurities may flow through the damaged exterior material depending on the pressure difference between the inside and outside of the battery. Aside from the fact that they are not good for the human body, expansion and reaction heat may occur, which may cause damage to the battery or fire.

Specifically, the lithium battery, which accounts for most of the battery, is at risk derived from the use of lithium metal. Lithium is highly reactive and has the characteristic of having a violent autocatalytic reaction. Lithium has a relatively low melting point of 181°C, and molten lithium can cause the battery to become out of control. For example, if the temperature rises above the melting point of lithium metal due to a technical defect, an explosive reaction may occur between lithium and the electrolyte.

Another hazard associated with lithium arises from contact with water. In this case, water molecules (H ₂ O) are decomposed into respective elements due to the strong reactivity of alkali metals, and hydrogen gas is formed. The explosion range of the hydrogen-air mixture is 4 to 75% by volume, and the risk of ignition is high, and even static electricity or electric sparks with very low ignition energy can be the ignition source of hydrogen explosion.

Another hazard from contact with water arises due to the direct current between the electrode potential and the battery terminals. Even if the inside of the electrode is unlikely to come into contact with water, water may be generated due to the voltage between the battery terminals, and in addition, it may come into contact with moisture in the air due to damage to the package. As a result, hydrogen gas is generated and there is a risk of hydrogen explosion.

In addition, the lithium battery is sealed to prevent gas leakage by the exterior material, and the material contained therein is made not to leak. However, due to mechanical damage or fire on the cell surface, toxic and flammable substances such as dust, gas, and liquid may leak. Oxides such as cobalt, nickel, and manganese are used in secondary batteries, and the smoke generated during a fire contains harmful and toxic substances generated from oxides. In the case of cobalt compounds, even as low as 25 mg of skin exposure can damage tumors, heart and kidneys, nickel compounds are associated with lung cancer and upper respiratory tract disorders.

The present invention accommodates the battery in a vacuum chamber that can block the external air in order to detect that the components generated when the battery casing is damaged are leaking out of the battery while intensive research is being conducted to solve this problem, and in the vacuum chamber It has been found that measurement accuracy can be improved by inducing air to flow back into a chamber having a sensor or the like. In particular, in the general process, the leaked components of the battery rapidly diffused into the air according to the flow of air, making it very difficult to measure. became

Referring to the drawings together, the secondary battery electrolyte leakage inspection system includes a vacuum chamber 100 including an upper housing 110 and a lower housing 120 disposed to face each other with a battery accommodating space therebetween, the vacuum chamber and the Similarly, it is provided in the form of a housing (chamber) to prevent the flow of fluid (air, electrolyte, or other components leaked from the battery) with the outside, but is connected to the receiving space of the vacuum chamber so that the flow of fluid can occur, and The sensor chamber 200 including a sensor (S) capable of checking components, temperature, humidity, etc., is connected to the space and fluid flow in the sensor chamber, and the air in the sensor chamber or vacuum chamber is sucked or The vacuum pump 300 capable of pushing air toward the sensor chamber or the vacuum chamber and the sensor chamber, the vacuum chamber, and the vacuum pump are sequentially connected to block the mixing of the air inside and outside, and the air in the accommodation space, etc. It is characterized in that it includes a connection part 400 for guiding the flow in a certain direction.

That is, in the secondary battery electrolyte leakage inspection system according to the present invention, sequentially from the vacuum chamber in which the battery is accommodated, the vacuum chamber-sensor chamber-vacuum pump is not mixed with external air through the connection part, and the fluid flow can occur. can be connected Therefore, when the vacuum pump performs the suction or discharge operation, the fluid in the internal space may be transferred from the vacuum chamber to the vacuum pump or from the vacuum pump to the vacuum chamber. In this process, as the fluid in the receiving space of the vacuum chamber is transferred toward the sensor chamber, it comes into contact with the sensor to measure the component or content of harmful substances in the electrolyte, or as the fluid of the vacuum pump is transferred to the vacuum chamber, it is transferred to the sensor chamber or inside the vacuum chamber. The remaining harmful components are washed away.

In addition, the leak inspection system for hazardous substances as described above each includes one vacuum chamber, a sensor chamber, a vacuum pump, and a connection unit connecting them, but in order to further increase the inspection efficiency, the vacuum chamber and the sensor chamber are paired to make a plurality of pairs It is preferable to provide In particular, when the vacuum chamber and the sensor chamber are connected in parallel as shown in FIG. 4(b), the pressure of the fluid in the vacuum chamber and the sensor chamber can be adjusted at once with one pump, and the control unit and each component can be connected more efficiently can

When the secondary battery electrolyte leak inspection system is described in more detail based on the measurement method shown in FIGS. 1 to 4,

a) opening the upper housing of the vacuum chamber, and accommodating the object to be detected (pouch cell) in the lower housing (S1);

b) closing the upper housing and opening the connection part (S2);

c) moving the fluid in the vacuum chamber to the sensor chamber by suctioning the vacuum pump (S3);

d) measuring any one or a plurality of measurement targets selected from the total volatile organic compound content, the electrolyte content, the carbon dioxide content, the humidity and the temperature in the fluid sucked through the sensor in the sensor chamber (S4);

e) stopping the operation of the vacuum pump and closing the connection part (S5); and

f) analyzing the measurement target measured by the sensor and determining whether the electrolyte leaks from the object (pouch cell) to be detected (S6);

can proceed, including

In the present invention, step a) is a step of accommodating a detection target (pouch cell) in the vacuum chamber, opening the upper housing using an opening/closing part, etc., and vacuuming the detection target (pouch cell) with a vacuum chuck. It is a step of transferring to the receiving space of the chamber.

In the present invention, the vacuum chamber provides a space for accommodating an object to be detected (pouch cell) such as a battery, and at the same time maintains a constant flow of a fluid around the object (pouch cell) or a concentration of a component in the fluid To do this, a connection part, which is a flow path communicating enough to generate a flow of fluid with the sensor chamber, may be provided on one surface. In addition, the vacuum chamber is a signal generating unit that generates a signal so as to easily confirm that the vacuum chamber accommodates the abnormally detected object (pouch cell) when the electrolyte is detected in the detected object (pouch cell). (not shown) may be further included.

Here, the vacuum chamber may provide a seal for maintaining a relatively lower pressure (vacuum pressure) than the pressure outside the housing corresponding to atmospheric pressure. The sealing is formed on the surface in contact with the upper housing and the lower housing or on the surface in contact with the connection part. By transferring the component to the sensor chamber, it is possible to determine the degree of damage or the time at which the battery is damaged from the content of the component in the fluid.

As described above, the vacuum chamber can more easily control the pressure of the receiving space by providing a seal for the receiving space inside, block the inflow of external fluid, and set and break the vacuum in the receiving space at the same time. .

In the present invention, the pressure outside the housing may correspond to atmospheric pressure, which is the external pressure of the vacuum chamber, and when the upper and lower housings are in close contact with each other to seal the vacuum chamber and suction of the fluid in the accommodation space occurs, in the accommodation space The fluid pressure may be lower than the atmospheric pressure.

The upper housing and the lower housing constituting the vacuum chamber may form an accommodating space therein by coupling similarly to a container, and may be coupled to each other or driven to be spaced apart as needed. For example, in a state in which the lower housing is fixed to an arbitrary facility, the upper housing may descend in the direction of the lower housing to seal the accommodation space. In addition, after determining whether the object (pouch cell) is damaged, the upper housing rises away from the lower housing or opens an additionally provided opening/closing door to open the vacuum chamber and expose the accommodation space to the outside. .

The opening and closing part and the vacuum chuck are for automating the inspection of the object (pouch cell) to be detected and further reducing the inspection time. is provided to automatically elevate or lower the upper housing before receiving or discharging the object (pouch cell) to be detected in the housing. It is provided as a kind of cylinder rod and is connected to the upper surface of the upper housing. In addition, one or a plurality of vacuum suction units are formed on a surface in contact with the upper housing, and a vacuum tube connected to the vacuum suction unit is provided inside to communicate with the vacuum suction unit, and a suction device such as a motor (not shown) ) may be provided to generate vacuum suction.

The vacuum chuck 700 is provided to transport and fix the object (pouch cell) to be detected, and is not limited in shape, but similarly to the opening/closing part, one on the surface in contact with the object (pouch cell). Alternatively, a plurality of vacuum suction units may be formed, and a vacuum tube connected to the vacuum suction unit may be provided in communication with the vacuum suction unit to generate vacuum suction by a suction device (not shown) such as a motor.

Accordingly, when the receiving space is opened by moving the upper housing by the opening/closing unit, the detected object (pouch cell) is moved to the inner surface of the lower housing by the vacuum chuck. When the object to be detected (pouch cell) is located in the accommodation space of the housing, the opening/closing unit moves the upper housing again to close the accommodation space. In addition, after the inspection is finished, the opening/closing unit moves the upper housing to open the receiving space, and the vacuum chuck comes into contact with the upper part of the detected object (pouch cell), sucks it, and removes it from the housing.

Next, as in step b), the upper housing is closed and the connection part is opened. Closing the upper housing is to block the flow of air between the inside and the outside of the vacuum chamber, because it is necessary to reduce the internal pressure in order to transfer the fluid inside the housing toward the sensor chamber to be described later.

In the present invention, the connection part 400 serves to connect the housing, the chamber, and the vacuum pump so that the flow of the fluid can occur, and for this purpose, it may be provided in the form of a tube to facilitate the transfer of pressure.

In addition, if necessary, the connection part may further include a throttle valve 410 to control the flow of internal flow according to the operation of the vacuum pump. The throttle valve is also called a throttle valve, and is a valve used to control the flow rate. In particular, the throttle valve can control the flow rate regardless of the viscosity of the fluid, and since the control flow rate can be linearly controlled, the pump can stably perform suction and discharge operations even when electrolytes can be included in the fluid as in the present invention. It is preferable to be able to do it.

One or more throttle valves may be provided between the housing and the chamber and at a connection part provided between the chamber and the vacuum pump. Through this, suction or discharge of a desired fluid can be adjusted for each chamber and housing through opening and closing of the connection part.

The throttle valve may have various shapes, but preferably a butterfly valve type. The butterfly-type throttle valve installs two semi-disk plates on a rotatable shaft for the passage on the pipe, and turns the shaft to change the position of the semi-disk from the vertical direction that blocks the flow of the fluid to the horizontal direction that does not obstruct the flow. It has a high flow control effect as a valve that can control the flow of

In addition, the throttle valve may be signally connected to a control unit to be described later to control opening and closing of each throttle valve as needed. For example, to measure the TVOC content after a certain time has elapsed after receiving the object (pouch cell), a throttle valve that connects the housing and the chamber independently of whether the pump is operating, and a throttle valve that connects the chamber and the vacuum pump can be closed to block the flow of fluid in the chamber.

The opening of the connection part in step b) opens all of the connection parts provided in the vacuum chamber and the sensor chamber, and the sensor chamber and the vacuum pump, and the opening of the connection part as described above may be made by the above-described throttle valve.

Next, as in steps c) and d), the vacuum pump is suctioned to move the fluid in the vacuum chamber to the sensor chamber for the transport of harmful components, and the total volatile organic compound content in the fluid sucked through the sensor in the sensor chamber , any one or a plurality of measurement targets selected from the content of electrolytic components, carbon dioxide content, humidity and temperature are measured.

When step c) and step d) are described in detail, the fluid in the housing, especially the air component, may change depending on whether the object to be detected (pouch cell) is damaged. The pump is sucked in and transferred to the sensor chamber, and when the transferred fluid in the housing comes into contact with the sensor, the sensor measures whether harmful components are present in the fluid, or whether the temperature or humidity has changed.

For example, if no electrolyte is discharged from the object (pouch cell) to be detected, the sensor will not detect any material change in the fluid even if the vacuum pump is sucked and the fluid in the housing is transferred to the sensor chamber. However, if the electrolyte is released from the object to be detected (pouch cell) for some reason, the released harmful components will be located in the receiving space of the housing in a gas or liquid state. It can detect changes and notify the user.

The sensor chamber has a space for accommodating the sensor therein similarly to the vacuum chamber, so that external air does not come into contact with the sensor inside, and the above-described connection part is provided on one surface to allow the fluid introduced from the vacuum chamber to pass or It allows the fluid of the vacuum pump to be discharged toward the sensor chamber.

In addition, the sensor chamber may have a structure that can be opened and closed like the vacuum chamber. Through this, the inside of the sensor or chamber can be cleaned or the sensor can be replaced as needed. In the case of having a structure that can be opened and closed as described above, a sealing means is provided so that the internal pressure can be maintained differently from the external pressure. desirable.

The sensor is located in the sensor chamber as described above, and when the flow of the fluid inside the system occurs due to the operation of the vacuum pump, it detects the components in the fluid introduced from the vacuum chamber to determine whether the object (pouch cell) is damaged. provided to do

Specifically, the sensor is capable of measuring any one or a plurality of measurement targets selected from the total volatile organic compound content of the fluid, the electrolyte content, the carbon dioxide content, humidity and temperature, and among them, the humidity or temperature is the humidity sensor and It can be measured with a temperature sensor, and the total volatile organic compound content, electrolyte content, carbon dioxide content, etc. of the fluid can be measured through a gas sensor. That is, the sensor includes the humidity sensor, the temperature sensor, and the gas sensor on one large substrate, and may further include a transmitter for transmitting the information received therefrom to a controller to be described later.

The gas sensor 210 may be largely divided into a solid electrolyte type, a catalytic combustion type, an electrochemical type, and a semiconductor type sensor. The semiconductor type gas sensor may be referred to as a semiconductor type micro gas sensor.

The basic principle of the semiconductor type gas sensor is ionized oxygen (O ^- , ^O2- ) adsorbed on the surface of the metal oxide semiconductor, oxidizing gas (Cl ₂ , NO, NO ₂ , etc.) and reducing gas (CH ₃ COCH ₃ , C ₂ H ₅ OH, CO, H ₂ , etc.) reacts to use the property of changing the electrical resistance.

The gas sensor is carbon monoxide (CO), methane (CH ₄ ), ethanol (CH ₂ H ₆ O), toluene (toluene), acetone (acetone), xylene (xylene, xylene), octane (octane), isobutylene (isobutylene), butyl acetate (butyl acetate), formaldehyde (formaldehyde), etc. can be detected. In addition, the types of gases that the gas sensor can detect or sense are very diverse, and are not limited to the above-described gases. That is, the gas sensor can detect or sense not only a gas harmful to the human body, but also a gas harmless or beneficial to the human body. For example, the gas sensor may detect the quality of air in a given environment, which means that the quality of the air may include not only harmful gas but also beneficial gas such as oxygen.

The semiconductor type gas sensor, when a specific gas is adsorbed to the sensing material of the sensor, by measuring the change in electrical conductivity of the sensing material, it is possible to detect the presence or absence of a gas above a certain concentration, so the sensitivity is excellent and the manufacturing process is easy. It is preferable because it is simple and can be manufactured in various types of sensors regardless of size.

Specifically, the gas sensor includes: a substrate including a first substrate 211 and a second substrate 212; a heating layer 213 positioned on the substrate; an electrode 214 positioned on the heating layer but provided to cover a portion of the top portion of the heating layer and having a through hole formed in the center thereof; and a sensing unit 215 provided to cover a portion of the electrode and the heating layer and including a metal oxide.

The substrate is for accommodating a heating layer, which will be described later, and may be provided to be fixed to the inner surface of the sensor chamber. In addition, a heating layer and an electrode are positioned on the upper portion, and a sensing unit including a metal oxide or the like is formed on the heating layer and the electrode.

The substrate is not limited in material, but may be provided as an insulating substrate or a conductive substrate. More specifically, a substrate such as sapphire, silicon oxide, alumina, or a metal on which an insulating layer made of an insulating material is deposited, a conductive oxide, a silicon substrate, etc. this can be used However, the electrode or the electrode line to be described later must be insulated to prevent a short circuit.

In particular, when a conductive substrate is used as the substrate, a substrate made of a material such as a semiconductor with high conductivity such as doped silicon, a metal such as stainless steel, a conductive oxide, or a conductive polymer may be used. Additional insulation is required.

The heating layer 213 is to provide heat to the sensing unit, and since metal oxides constituting the sensing unit, which will be described later, operate in an environment of 200° C. or higher, it is provided at the lower end of the sensing unit to provide the same temperature. will be.

The heating layer is not limited in type or specific configuration as long as it can provide heat of 200° C. or higher to the sensing unit, but is electrically connected to a heating electrode (not shown) including a metal having a resistance and electrically connected to the heating electrode. It may include a connection layer (not shown) that provides power.

The electrode 214 is formed to supply power to the gas sensor, and may be electrically connected to the electrode line 216 through a wire. In addition, it is preferable that the electrode is formed adjacent to the substrate and the heating layer, and an opening is formed to accommodate the sensing unit.

The electrode or the electrode line is not limited to a forming method, and may be formed by, for example, patterning the heating layer or the substrate through lithography. In this case, the components forming the electrode and the like may include metals, but are not limited to platinum, gold, titanium, palladium, iridium, silver, rubidium, nickel, stainless, aluminum, molybdenum, chromium, tungsten, Indium tin oxide (ITO), may include any one or a plurality selected from the fluorine tin oxide.

The sensing unit 215 is for detecting the presence or absence of harmful components in the gas, and may be formed to protrude on the electrode and the heating layer by molding a composition containing a metal oxide. When it is formed to protrude as described above, since the surface area that can be in contact with the air increases that much, the detection performance of harmful components can be further improved.

As a metal oxide forming the sensing part, for example, SnO ₂ , TiO ₂ , ZnO, CuO, NiO, CoO, In ₂ O ₃ , WO ₃ , MgO, CaO, La ₂ O ₃ , Nd ₂ O ₃ , Y ₂ O ₃ , CeO ₂ , PbO, ZrO ₂ , Fe ₂ O ₃ , Bi ₂ O ₃ , V ₂ O ₅ , VO ₂ , Nb ₂ O ₅ , Co ₃ O ₄ and Al ₂ O ₃ Any one or multiple days selected from can

In general, the metal oxide may be added in the form of nano-sized particles, but it is preferable to add the metal oxide in the form of nanofibers prepared by electrospinning with a spinning solution containing them. Through this, it is possible to have selectivity for various gases that may be variously required according to high sensitivity characteristics required to detect trace amounts of gas and application fields.

The composition for forming the sensing unit may further include a carbon component such as graphene in addition to the metal oxide. Since the graphene is formed through planar structural bonding of carbon atoms, it basically has a wide two-dimensional planar structure. Accordingly, when binding it to the metal oxide semiconductor nanofiber, the graphene can further improve the gas sensing performance as the catalytic function is activated when an external gas comes into contact with the metal oxide semiconductor nanofiber.

As the graphene catalyst material, one of single-layer graphene, multi-layer graphene, graphite, graphene oxide, or graphene quantum dots is used, or two or more of these are mixed. It is also possible to use At this time, although the mixing ratio is not limited, it is preferable to mix in an amount of 0.001 to 20 parts by weight based on 100 parts by weight of the metal oxide semiconductor nanofiber.

In addition, the composition may further include a binder capable of mixing them and maintaining the shape. The binder can be used without limitation as long as it is a component capable of maintaining its shape and having heat resistance and insulation properties, and preferred examples of these components include trimethoxy(methyl)silane (TMMS), tetramethoxysilane (TMOS), tetraethoxysilane ( TEOS), tetra-n-propoxysilane, tetra-i-propoxysilane, and tetra-n-butoxy silane. In addition to the above components, to further improve moldability, organic materials such as polyvinylpyrrolidone (PVP), polyvinylidene fluoride (PVDF), polyvinyl alcohol (PVA), polyvinyl acetate (PVAc), polystyrene (PS), polymethyl methacrylate (PMMA), poly (n -butylacrylate)(PBA), polyacrylonitrile(PAN), styrene acrylonitrile(SAN), polyamide-imide(PAI), styrene butadiene rubber(SBR), carboxymethyl cellulose(CMC), alginate, polyacrylic acid(PAA), polyesteramides(PEA) , polyethylene (PE), polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), polyurethane (PU), polyester, epoxy, ethylene glycol (EG), polychloroprene, polyisoprene and polybutadiene, etc. may be further included.

Although the amount of the binder is not limited, it is preferable that the metal oxide semiconductor nanofiber be mixed enough to be in contact with the fluid while maintaining the shape of the sensing part, and specifically, in the range of 30 to 100 parts by weight relative to 100 parts by weight. it is preferable

The method of forming the sensing unit is also not limited. Specifically, a liquid or gel phase composition is prepared by mixing a sufficient amount of a solvent capable of dissolving the binder together with the above components, and then applying it on top of a substrate provided with an electrode and a heating layer, and heat-treating it It can be produced by curing.

As described above, the gas sensor can measure the total volatile organic compounds (TVOC) content in the fluid very accurately. Specifically, the gas sensor can measure an output range of up to 60,000 ppb (parts per billion, 10 ^-9 ) within 1 second, and it varies depending on the total volatile organic compound content in the fluid, but up to 2008 ppb 1 ± ppb, from 2008 to Up to 11,110 ppb may have an accuracy of ±6 ppb, and from 11,110 to 60,000 ppb may have an accuracy of ±32 ppb.

In addition, the temperature sensor, the moisture sensor, and the carbon dioxide sensor are for measuring the temperature, humidity, and carbon dioxide in the fluid, respectively, and if it is a sensor commonly used in the art, it can be used without limitation to the type, and the specifications of the sensors are Although not limited, each ±30 ppm / 400 to 10,000 ppm / 1 second to 1 minute (accuracy, output range, measurement speed, abnormal carbon dioxide sensor), ±1.5℃ / -40° to 120° / 1 second (abnormal temperature sensor) ), ±2 %RH / 0 to 100 %RH / 1 second (more than humidity sensor) can have measurement specifications.

As described above, the sensor according to the present invention includes a gas sensor, a temperature sensor, a moisture sensor, and a carbon dioxide sensor on one substrate. In particular, it has the advantage of increasing the accuracy of determining whether the object (pouch cell) is damaged by measuring the change in temperature, humidity, and carbon dioxide of the fluid according to the damage of the battery casing.

The vacuum pump 300 is provided to set the fluid pressure inside the chamber and the housing to a desired degree, and is connected to generate a flow of fluid with the chamber and the housing through a connection part to be described later, and both suction and discharge operations are possible. Thus, the pressure of the fluid inside the chamber and the housing may be lower than atmospheric pressure or a vacuum state, or it may be maintained higher than atmospheric pressure.

The vacuum pump is not limited in its form or configuration, and specifically includes a valve capable of preventing the reverse flow of fluid together with a tube capable of sucking or discharging air, as in Korean Patent Application Laid-Open No. 10-2017-7011372, etc. Any one or a plurality of pumping devices selected from a screw pump, a claw pump, a multi-stage Roots pump, a diaphragm pump, a dry rotary vane pump, and a lubricated rotary vane pump may include

In addition, the vacuum pump may receive a command to the degree of vacuum, operation, stop, etc. from a control unit to be described later. That is, when the detection target (pouch cell) is accommodated in the accommodation space of the housing, the control unit commands the suction operation of the vacuum pump after the housing is opened and closed. If the vacuum pump carries out the command after receiving the command, the pressure in the housing and the chamber can be set to a pressure relatively lower than atmospheric pressure to the extent set by the control unit. In addition, after measuring the content of harmful substances in the fluid after vacuum, the control unit may again command the vacuum pump to discharge, and through this, the vacuum pump operates so that the pressure in the housing and chamber is equal to atmospheric pressure to open and close the housing. It is possible to smoothly or remove the remaining or adhering harmful substances in the housing or chamber.

As described above, when information on hazardous substances in the fluid is measured through the sensor, as in steps e) and f), first stop the operation of the vacuum pump and close the connection part to block the flow of the fluid, then control the measured data By sending it to 500 , it is determined whether the current to be detected (pouch cell) is leaking electrolyte, and this is disclosed to the user.

In the present invention, the control unit 500 checks any one or a plurality of information selected from the total volatile organic compound content, the electrolytic component content, the carbon dioxide content, humidity and temperature of the fluid, and based on this, the detected object (pouch cell) It plays a role in determining whether or not harmful substances leak in .

Although not limited, the control unit includes a processor for processing the information of the fluid received from the sensor, a display for providing a processed result to the user, and in addition, a storage unit or a power supply unit for storing data processed by the processor as needed may include more.

The processor directly processes the fluid information received from the sensor, controls and communicates components such as the vacuum pump described above, and executes calculations or data processing thereon. For example, the processor may control a plurality of sensors or throttle valves connected by driving an operating system or an application program, and may process data received from the sensors or perform an operation. In addition, by comparing the calculated result with a set value, it is finally determined whether the electrolyte is discharged from the detected object (pouch cell) accommodated in the housing, and it can be transmitted to a display or the like to provide it to the user.

In particular, the processor may determine whether harmful substances are emitted from the object (pouch cell) to be detected based on the information received from the sensor, and in particular, whether or not the electrolyte is leaked due to damage to the exterior material of the battery. For example, it determines whether leakage occurs by comparing the normal battery information stored in the storage or preset information with information measured by a sensor. Abnormal rise in temperature, increase in carbon dioxide concentration, increase in humidity, If there is an increase, it can be determined that an electrolyte or the like has leaked from the currently measured battery.

In addition, the processor may perform a designated function in response to the discharge of the secondary battery electrolyte. The processor may classify according to the degree of emission of hazardous substances and give a command to the housing in which the hazardous substance has leaked so as to fit each grade to emit a signal corresponding thereto, for example, a beep sound, lighting, etc., in addition to each throttle In particular, when a plurality of vacuum chambers and sensor chambers are provided by controlling the valves or sensors one by one, it is determined whether the electrolyte is released for each detected object (pouch cell) accommodated in each vacuum chamber, and a hazardous substance is detected In the vacuum chamber in which the sieve (pouch cell) is accommodated, a vacuum pump and a throttle valve are operated to supply a fluid to the housing to clean the remaining electrolyte.

The display provides information corresponding to the leaking state of the hazardous substance to the user under the control of the processor, and may be provided as a kind of image, text, sound, video, or the like, as various notifications. For example, the display displays a notification indicating that the current detected object (pouch cell) is abnormal in response to the degree of leakage of harmful substances, or informs how many harmful substances are released per hour In the case of a place, notifications such as ventilation or opening, handling caution warning, after-sales service recommendation, etc. may be displayed, or one or more of restrictions on use of some housings in the system may be displayed.

In addition, the storage unit is for storing programs or instructions necessary for the operation of the processor, criteria for determination of hazardous substances, data of previously detected hazardous substances, and the like, and may accumulate and store the leakage state according to the detection time, and may be stored in the housing or sensor chamber. It is possible to store one or more context information among temperature, humidity, carbon dioxide concentration, and TVOC concentration.

The control unit may include a communication unit capable of communicating with the housing or the sensor chamber to perform the above-described contents. The communication means of the communication unit is not limited in the present invention, and any one or more of wired and wireless communication may be applied.

As described above, if it is determined whether the electrolyte leaks from the object (pouch cell), the control unit may command to change the operation of the system according to the result. As shown in FIG. 1 , when the electrolyte is not detected, the test may be finished and the detection target (pouch cell) may be removed from the housing (S7-1, S8-1). Separately, when electrolyte is detected in the object to be detected (pouch cell), as in step g), a signal is generated in the vacuum chamber accommodating the object (pouch cell) and the electrolyte is leaked from the object (pouch cell). ) is classified (S7-2).

In step g), first, it is determined that leakage of the electrolyte has occurred based on the operation result performed by the control unit, and then the control unit generates a user-identifiable signal in the housing accommodating the corresponding detected object (pouch cell). send the command Thereafter, by providing the signal to the user in the corresponding housing, the user can easily check in which housing among the various housings the object (pouch cell) leaking the electrolyte is accommodated.

At this time, the shape of the signal generated in the vacuum chamber is not limited in the present invention. For example, it may have a form such as a beep sound or LED lighting, and preferably, LED lighting that can be easily checked with the naked eye is preferable.

When the housing accommodating the detected object (pouch cell) from which the electrolyte has leaked as described above is checked, as in step h), the upper housing of the vacuum chamber in which the detected object (pouch cell) from which the electrolyte has leaked is accommodated is opened, The vacuum pump is discharged to discharge the fluid to the outside of the vacuum chamber.

In step h), the upper housing is first opened, and then the corresponding object (pouch cell) is removed using a vacuum chuck. And the vacuum pump is discharged to discharge harmful substances from the vacuum pump to the outside. Through this, by removing harmful components that may remain in the vacuum pump, the connection part, the sensor, the sensor chamber, and the vacuum chamber, it is possible to increase the measurement accuracy of the electrolyte leakage to be performed in the future.

The type, release rate, and release time of the fluid used in step h) are not limited in the present invention. For example, the fluid may be general air, may be an inert gas such as nitrogen, or water may be used.

Hereinafter, the present invention will be described in more detail through Examples and Comparative Examples. However, the following examples are only examples for explaining the present invention in more detail, and the present invention is not limited to the following examples.

The specifications of the sensors used in Examples and Comparative Examples are as follows.

[Table 1]

The sensors listed in Table 1 are mounted on the sensor module shown in FIG. As a result of passing the mixed gas to the sensor module and inspecting it, it was confirmed that each component in the mixed gas was stably detected for each set time (1 second) within the range of 1 to 32 ppb.

As described above, although the present invention has been described with reference to limited embodiments and drawings, the present invention is not limited to the above embodiments, and various modifications and variations from these descriptions are provided by those skilled in the art to which the present invention pertains. This is possible. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined by the following claims as well as the claims and equivalents.

100: vacuum chamber
110: upper housing
120: lower housing
121: accommodation space
200: sensor chamber
210: gas sensor
211: first substrate
212: second substrate
213: heating layer
214: electrode
215: sensing unit
216: electrode line
300: vacuum pump
400: connection
410: throttle valve
500: control unit
600: opening and closing part
700: vacuum chuck
B: Detected object (pouch cell)
S: sensor

Claims (10)

a vacuum chamber that provides a space for accommodating a detection target therein through coupling, and includes a housing capable of shielding the accommodating space of the detection target from the outside and a housing opening/closing door;
an opening and closing unit for automatically opening and closing the housing; and
a vacuum chuck for inserting or discharging a detection target (pouch cell) into the housing after the housing is opened;
a sensor chamber accommodating the sensor therein; and
a connection unit sequentially connecting the vacuum chamber, the sensor chamber, and the vacuum pump;
includes,
The connection part includes a connection pipe connecting the vacuum chamber and the sensor chamber, the sensor chamber and the vacuum pump, respectively,
The connection pipe can be opened and closed so as to further include a throttle valve capable of controlling the flow of the fluid in the vacuum chamber or the sensor chamber from the vacuum chamber to the sensor chamber.
The method of claim 1,
The sensor is a secondary battery electrolyte leakage test system, characterized in that for measuring any one or a plurality of measurement targets selected from the total volatile organic compound content, electrolyte content, carbon dioxide content, humidity and temperature of the fluid.
3. The method of claim 2,
The gas sensor for measuring the total volatile organic compound content of the fluid,
Board;
a heating layer positioned on the substrate;
an electrode positioned on the heating layer but provided to cover a portion of the top portion of the heating layer and having a through-hole formed in the center thereof; and
a sensing unit provided to cover a portion of the electrode and the heating layer and including a metal oxide;
A secondary battery electrolyte leakage inspection system comprising a.
delete delete The method of claim 1,
The secondary battery electrolyte leak inspection system,
It is connected to the sensor to check any one or a plurality of information selected from total volatile organic compound content, electrolyte content, carbon dioxide content, humidity and temperature of the fluid, and select from vacuum pump, throttle valve, opening/closing part and vacuum chuck Secondary battery electrolyte leakage inspection system, characterized in that it further comprises a control unit for controlling the driving of any one or both.
The method of claim 1,
The secondary battery electrolyte leakage inspection system comprises a plurality of pairs of a vacuum chamber and a sensor chamber as a pair.
An electrolyte leakage inspection method using the secondary battery electrolyte leakage inspection system according to claim 1, the inspection method comprising:
a) opening the opening/closing door of the vacuum chamber and accommodating the object to be detected in the lower housing;
b) closing the upper housing and opening the connection part;
c) moving the fluid in the vacuum chamber to the sensor chamber by suctioning the vacuum pump with vacuum pressure;
d) measuring any one or a plurality of measurement targets selected from the total volatile organic compound content, the electrolyte content, the carbon dioxide content, the humidity and the temperature in the fluid sucked through the sensor in the sensor chamber;
e) driving the vacuum pump and closing the connection part;
f) analyzing the measurement target measured by the sensor to determine whether the detection object leaks the electrolyte;
g) classifying the object from which the electrolyte has leaked by generating a signal in the vacuum chamber accommodating the detected object when a hazardous substance is detected in the object to be detected; and
h) opening the housing of the vacuum chamber in which the object to be detected, from which the electrolyte is leaked, is accommodated, and discharging the vacuum pump to discharge the fluid to the outside of the vacuum chamber;
Electrolyte leakage test method comprising a. delete delete

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