Gas collection device

Abstract

Disclosed is a gas collection device capable of sampling gas generated in a secondary battery by adjusting the concentration of the gas to a level suitable for analysis.

Description

APPARATUS FOR COLLECTING GAS

[0001] This application claims the benefit of priority from Korean Patent Application No. 10-2023-0183114, filed December 15, 2023, the entire disclosure of which is incorporated herein by reference.

[0002] The present application relates to a gas collection device, and more specifically, to a gas collection device capable of sampling gas generated inside a secondary battery by adjusting the concentration to an appropriate level for analysis.

[0003] Secondary batteries are batteries that can be reused repeatedly through the process of discharging, which converts chemical energy into electrical energy, and charging, which converts electrical energy into chemical energy. Commonly known types include nickel-cadmium (Ni-Cd) batteries, nickel-metal hydride (Ni-MH) batteries, lithium-metal batteries, lithium-ion (Li-ion) batteries, and lithium-ion polymer batteries. Among these secondary batteries, lithium secondary batteries have been commercialized and are widely used due to their high energy density and voltage, long cycle life, and low self-discharge rate.

[0004] Inside the lithium secondary battery, hydrogen, oxygen, nitrogen, carbon monoxide, carbon dioxide, and C are produced according to the charge and discharge reaction. n H 2n-2 (n=2~5), C n H 2n (n=2~5), C n H 2n+2 Various types of gases such as hydrocarbons and other organic gases (n=1~5) can be generated.

[0005] Furthermore, lithium secondary batteries generate large amounts of gas as the electrolyte decomposes and degrades with repeated charging and discharging. This phenomenon varies depending on the battery design and usage. Therefore, analyzing the gases generated within the battery to infer the battery degradation mechanism is essential during battery development.

[0006] Therefore, capturing and accurately analyzing the gases generated within secondary batteries is crucial. Information on the composition and content of various gases generated during charging and discharging of lithium secondary batteries is useful for developing battery materials, optimizing battery manufacturing processes, and identifying the causes of battery failures. To achieve this, the development of technologies to capture gases generated within secondary batteries is crucial.

[0007] The following process can be performed as one of the methods for analyzing gases generated inside a secondary battery.

[0008] To capture the gas to be analyzed generated inside the secondary battery, a hole is formed in the case of the secondary battery, and the gas to be analyzed is extracted through the hole.

[0009] The extracted target gas is diffused into a sealed gas diffusion space.

[0010] The target gas diffused in the gas diffusion space is sampled in a sampling container.

[0011] Gas analysis is performed by injecting the sampled target gas into a sampling container into a gas analysis device such as GC-MS.

[0012] In the above process, the sensitivity of the gas analysis device is affected by the concentration of the target gas. If the concentration of the target gas is too low, purified analysis is difficult. The concentration of the target gas can be determined by the volume of the gas path, including the gas diffusion space and sampling vessel. Accurate quantitative analysis requires accurate volume values ​​of the gas diffusion space and gas path within the entire gas analysis system, but this is not easy. Therefore, gas capture technology for such gas analysis systems is necessary.

[0013] The present invention relates to a gas collection device, and provides a gas collection device capable of sampling an analysis target gas generated inside a secondary battery by adjusting the concentration to an appropriate level for analysis.

[0014] The technical problems to be solved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0015] The gas collection device is

[0016] A gas extraction unit for extracting gas from a target cell;

[0017] A gas diffusion unit having a gas diffusion space for receiving and diffusing the extracted gas from the gas extraction unit;

[0018] A sampling unit having a gas sampling space for receiving and sampling the diffused gas from the gas diffusion unit; and

[0019] A control unit for controlling the above gas diffusion unit is included,

[0020] The volume of the above gas diffusion space is variable,

[0021] The volume of the above gas sampling space may be fixed.

[0022] According to one embodiment, the gas extraction unit may include a gas extraction chamber portion having a battery receiving space in which the analysis target cell is received, and a punching portion for punching a gas extraction hole in the analysis target cell received in the battery receiving space.

[0023] According to one embodiment, the gas diffusion unit includes a base plate portion formed as a plane perpendicular to the vertical direction; a cylindrical side wall portion having a lower end fixed to the base plate portion and extending in the vertical direction; a vertical moving portion having an upper end fixed to the cylindrical side wall portion and moving in the vertical direction; a guide support portion guiding the vertical moving portion's movement in the vertical direction; and a vertical driving portion providing a driving force for the vertical moving portion to move in the vertical direction, wherein the gas diffusion space may be formed as a space surrounded by the base plate portion, the cylindrical side wall portion, and the vertical moving portion.

[0024] According to one embodiment, a gas inlet / outlet is formed in the base plate portion, and the gas may be injected or discharged into the gas diffusion space through the gas inlet / outlet.

[0025] According to one embodiment, the cylindrical side wall portion may be a bellows structure.

[0026] According to one embodiment, the vertical moving part may include a cylindrical body member extending in the vertical direction, and an upper plate member formed in a plane perpendicular to the vertical direction and having an upper end of the body member fixedly coupled to a bottom surface, an upper end of the cylindrical side wall portion may be fixedly coupled to a bottom surface of the upper plate member, the body member may be positioned inside the cylindrical side wall portion, and a space surrounded by a lower end of the body member, an upper surface of the base plate portion, and an inner circumferential surface of the cylindrical side wall portion may be formed as the gas diffusion space.

[0027] According to one embodiment, when the vertical moving part is lowered to the lowest point, the lower end of the body member may contact the upper surface of the base plate part, and all inner surfaces of the cylindrical side wall part may face the outer surface of the body member.

[0028] According to one embodiment, the upper plate member is formed in a disk shape, the guide support member is formed in a cylindrical shape extending in the vertical direction, the inner diameter of the guide support member is the same as the diameter of the upper plate member, and the upper plate member may slide and be guided on the inner circumferential surface of the guide support member.

[0029] According to one embodiment, the lower end of the guide support is fixed to the upper surface of the base plate, a guide hole extending vertically is formed on a side surface of the guide support, the vertical driving unit has one end inserted into the guide support through the guide hole and the other end positioned outside the guide support, and may include a power transmission member coupled to the upper surface of the upper plate member, a vertical movement shaft extending vertically and coupled to the other end of the power transmission member, and a driving actuator supported on the base plate and moving the vertical movement shaft vertically.

[0030] The gas collection device of the present invention may be capable of sampling the gas to be analyzed generated inside a secondary battery by adjusting the concentration to an appropriate level for analysis.

[0031] The gas collection device of the present invention can control the speed of gas diffusion by adjusting the volume of the gas diffusion space with a driving force operating on the gas diffusion chamber unit when sampling internal gas generated in a target battery such as a cylindrical or square secondary battery.

[0032] The gas collection device of the present invention can sample the gas to be analyzed at an optimized concentration for analysis by varying the volume of the gas diffusion space when sampling the gas to be analyzed diffused in the gas diffusion space of the gas diffusion chamber unit to the sampling unit.

[0033] Figure 1 is a conceptual diagram showing a gas collection device according to one embodiment.

[0034] Figure 2 is a side view of a gas diffusion unit according to one embodiment.

[0035] Figures 3 and 4 are cross-sectional views showing a longitudinal section of a gas diffusion unit according to one embodiment.

[0036] Fig. 5 is a perspective view showing a guide support according to one embodiment.

[0037] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. Throughout this process, the sizes and shapes of components depicted in the drawings may be exaggerated for clarity and convenience. Furthermore, terms specifically defined in consideration of the structure and operation of the present invention may vary depending on the intentions or practices of the user or operator. Definitions of these terms should be based on the overall content of this specification.

[0038] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms “center,” “upper,” “lower,” “left,” “right,” “vertical,” “horizontal,” “inner,” “outer,” “one side,” “other side,” etc., is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present invention is normally placed when used, and is only for the purpose of explaining and briefly explaining the present invention, and does not suggest or imply that the indicated device or element must have a specific orientation and be configured or operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0039] Fig. 1 is a conceptual diagram illustrating a gas collection device according to an embodiment. Fig. 2 is a plan view illustrating a side view of a gas diffusion unit (100) according to an embodiment. Figs. 3 and 4 are cross-sectional views illustrating a longitudinal section of a gas diffusion unit (100) according to an embodiment. Fig. 5 is a perspective view illustrating a guide support member (140) according to an embodiment.

[0040] Hereinafter, the gas collection device of the present invention will be described in detail with reference to FIGS. 1 to 5.

[0041] The gas capture device may use a secondary battery having a rigid case, such as a cylindrical secondary battery or a square secondary battery, as the analysis target battery (11), but is not limited thereto.

[0042] The gas capture device may be for capturing gases generated inside the secondary battery, i.e., gases generated from active materials, binders, additives, electrolytes, etc.

[0043] The gas capture device may include three sealed spaces. Specifically, it may be provided as a battery receiving space (211), a gas diffusion space (121), and a gas sampling space.

[0044] In the gas capture device, the battery receiving space (211) may be a space where the target battery (11) is stored. For example, in the battery receiving space (211), the target battery (11) may have a perforated hole formed in the case. In addition, the target gas generated inside the target battery (11) may be initially discharged from the target battery (11) in the battery receiving space (211), and depending on the situation, the target gas and the electrolyte may be mixed in the battery receiving space (211).

[0045] The gas diffusion space (121) may be a space for controlling the concentration and pressure of the gas to be analyzed. The volume of the gas diffusion space (121) may be variable. Specifically, the volume of the gas diffusion space (121) is controlled by a control unit, and the concentration and pressure of the gas to be analyzed can be controlled to a state optimized for analysis.

[0046] The gas sampling space may be a space for storing the target gas for analysis in an optimized state. The gas sampling space may be connected to a gas chromatography-mass spectroscopy (GC-MS), a gas chromatography-pulsed discharge detector (GC-PDD), a gas chromatography-thermal conductivity detector (GC-TCD), a gas chromatography-flame ionization detector (GC-FID), a Fourier transform infrared spectroscopy (FT-IR), and a Raman spectroscopy.

[0047] As shown in FIG. 1 and FIG. 2, the gas collection device of the present invention,

[0048] A gas extraction unit (200) that extracts the gas to be analyzed from the inside of the analysis target cell (11);

[0049] A gas diffusion unit (100) having a gas diffusion space (121) for receiving and diffusing the gas to be analyzed from the gas extraction unit (200);

[0050] A sampling unit (300) having a gas sampling space for receiving and sampling gas diffused in the above gas diffusion space (121); and

[0051] It may include a control unit (not shown) that controls the above gas diffusion unit (100).

[0052] The control unit may be a combination of hardware and software and may be a computing device for controlling the gas extraction unit (200), the gas diffusion unit (100), and the gas sampling unit (300).

[0053] In the gas capture device, the volume of the gas diffusion space (121) may be variable, and the volumes of the battery receiving space (211) and the gas sampling space may be fixed.

[0054] The gas capture device can prevent gas from being dissolved again in the electrolyte by providing a gas diffusion space (121) and a battery receiving space (211) as separate spaces, thereby improving the accuracy of quantitative analysis.

[0055] The gas collection device can control the gas diffusion rate by changing the volume of the gas diffusion space (121) through a control unit, and can adjust the concentration of the analysis target gas sampled in the gas sampling space.

[0056] As illustrated in FIG. 1, the gas extraction unit (200) may include a gas extraction chamber portion (210) in which a battery receiving space (211) for receiving a battery (11) to be analyzed is formed inside, and a punching portion (220) for punching a gas extraction hole in the case of the battery (11) to be analyzed received in the battery receiving space (211). A jig (not shown) for fixing the battery (11) to be analyzed in a fixed position may be provided inside the gas extraction chamber portion (210). In addition, the gas extraction chamber portion (210) may be provided with a heater for heating the battery (11) to be analyzed, a chiller for cooling the battery (11) to be analyzed, an impact means or vibration means for applying a physical force to the battery (11) to be analyzed, a charge / discharge module for charging or discharging the battery (11) to be analyzed, etc.

[0057] The punching unit (220) may include a punching needle that penetrates the case of the battery (11) to be analyzed. The punching needle is located in the battery receiving space (211), and the punching unit (220) may further include a driving means for providing driving force to the punching needle from the outside of the gas extraction chamber unit (210).

[0058] As shown in FIG. 2 and FIG. 3, the gas diffusion unit (100)

[0059] A base plate portion (110) formed as a plane perpendicular to the vertical direction;

[0060] A cylindrical side wall portion (120) having a lower portion fixed to the base plate portion (110) and extending in the vertical direction;

[0061] A vertical moving part (130) in which the upper part of the cylindrical side wall (120) is fixed and moves up and down;

[0062] A guide support member (140) that guides the vertical movement of the vertical moving member (130); and

[0063] The above vertical moving part (130) may include a vertical driving part (150) that provides driving force for moving in the up and down direction.

[0064] The space surrounded by the base plate portion (110), the cylindrical side wall portion (120), and the vertical moving portion (130) may form the gas diffusion space (121).

[0065] The above base plate portion (110) may be a plate of a rigid material having a flat shape perpendicular to the vertical direction. For example, the material of the base plate portion (110) may be SUS.

[0066] A gas inlet (111) is formed in the base plate portion (110), and the gas to be analyzed may be injected or discharged into the gas diffusion space (121) through the gas inlet (111). The center of the gas inlet (111) may be located at the center of a circular area of ​​the base plate portion (110) that faces the cylindrical side wall portion (120). A flow path connected to the sampling unit (300) and the gas extraction unit (200) may be connected to the gas inlet (111). The flow path connected to the gas inlet (111) may include a hose, a tube, a pipe, or the like. As illustrated in FIG. 1, the flow path connected to the gas inlet (111) may branch off at a specific point and branch off to the sampling unit (300) and the gas extraction unit (200), respectively.

[0067] A valve may be provided in a passage connecting the gas inlet (111) and the specific point, and the valve may be controlled by a control unit. In addition, a valve may also be provided in a passage connecting the specific point and the gas extraction unit (200), and the valve may also be controlled by a control unit. As illustrated in FIG. 1, the sampling unit (300) may include a sampling container (320) in which a gas sampling space, which is a space in which an analysis target gas is sampled and stored at an optimal pressure and concentration, is formed, and an opening / closing valve (310) for opening and closing the sampling container (320). The opening / closing valve (310) may be connected to a passage branched from the specific point. The opening / closing valve (310) may also be controlled by a control unit.

[0068] As illustrated in FIGS. 3 and 4, the cylindrical side wall portion (120) may be formed in a cylindrical shape having a vertical central axis. The cylindrical side wall portion (120) may be extended or contracted in the vertical direction. The inner diameter of the cylindrical side wall portion (120) may be fixed when extended or contracted in the vertical direction. For example, the cylindrical side wall portion (120) may be formed in a bellows structure.

[0069] The above vertical moving part (130) may include a cylindrical body member (131) extending in the vertical direction, and an upper plate member (133) formed as a plane perpendicular to the vertical direction and having the upper end of the body member (131) fixedly joined to the bottom surface.

[0070] The upper end of the cylindrical side wall portion (120) is fixedly joined to the lower surface of the upper plate member (133), and the body member (131) is positioned inside the cylindrical side wall portion (120), and a space surrounded by the lower end of the body member (131), the upper surface of the base plate member (110), and the inner surface of the cylindrical side wall portion (120) may form the gas diffusion space (121). At this time, an ideal structure may be one in which the inner diameter of the cylindrical side wall portion (120) and the outer diameter of the body member (131) are the same, and the coefficient of friction between the outer surface of the body member (131) and the inner surface of the cylindrical side wall portion (120) is 0.

[0071] When the vertical moving part (130) is lowered to the lowest point, the lower end of the body member (131) may contact the upper surface of the base plate part (110), and the entire inner surface of the cylindrical side wall part (120) may face the outer surface of the body member (131). That is, in an ideal structure, the volume of the gas diffusion space (121) in the lowest point lowered state of the vertical moving part (130) as shown in FIG. 4 may be 'O'.

[0072] The upper plate member (133) is formed in a disk shape, the guide support member (140) is formed in a cylindrical shape extending in the vertical direction, the inner diameter of the guide support member (140) is the same as the diameter of the upper plate member (133), and the upper plate member (133) may slide and be guided on the inner surface of the guide support member (140). For example, in an ideal state, the coefficient of friction between the side surface of the upper plate member (133) and the inner surface of the guide support member (140) may be 0. The upper plate member (133) may have a predetermined thickness to prevent the position from being twisted when moving in the vertical direction.

[0073] As shown in Fig. 5, the lower part of the guide support part (140) is fixed to the upper surface of the base plate part (110), and a guide hole (141) extending in the vertical direction can be formed on the side of the guide support part (140).

[0074] The vertical driving unit (150) may include a power transmission member (151) having one end inserted into the guide support member (140) through the guide hole (141) and the other end of the power transmission member (151) located outside the guide support member (140), a vertical movement shaft (152) extending in the vertical direction and coupled to the other end of the power transmission member (151), and a driving actuator (153) supported on the base plate part (110) and moving the vertical movement shaft (152) in the vertical direction.

[0075] The power transmission member (151) may be provided as a support made of a rigid material in the shape of a rod extending in a direction perpendicular to the vertical direction.

[0076] The power transmission member (151) may be coupled to the upper surface of the upper plate member (133). More specifically, the lower surface of the one end side of the power transmission member (151) inserted into the guide support member (140) through the guide hole (141) may be attached to the upper surface of the upper plate member (133).

[0077] While the embodiments of the present invention have been described above, they are merely exemplary, and those skilled in the art will appreciate that various modifications and equivalent embodiments are possible. Therefore, the true technical protection scope of the present invention should be defined by the following claims.

[0078] [Explanation of symbols]

[0079] 11... Analysis target cell 100... Gas diffusion unit 110... Base plate 111... Gas inlet 120... Cylinder side wall 121... Gas diffusion space 130... Vertical moving part 131... Body member 133... Top plate member 140... Guide support 141... Guide hole 150... Vertical driving part 151... Power transmission part 152... Vertical moving shaft 153... Driving actuator 200... Gas extraction unit 210... Gas extraction chamber 211... Battery receiving space 220... Punching part 300... Sampling unit 310... Opening / closing valve 320... Sampling container

Claims

1. A gas extraction unit for extracting gas from the battery; A gas diffusion unit having a gas diffusion space for receiving and diffusing the extracted gas from the gas extraction unit; A sampling unit having a gas sampling space for receiving and sampling the diffused gas from the gas diffusion unit; and A control unit for controlling the above gas diffusion unit is included, The volume of the above gas diffusion space is variable, A gas capturing device wherein the volume of the above gas sampling space is fixed.

2. In paragraph 1, The above gas extraction unit, A gas extraction chamber section having a battery receiving space in which the above battery is received, and A gas collection device including a punching section for punching a gas extraction hole in the battery accommodated in the battery accommodation space.

3. In paragraph 2, The above gas diffusion unit, A base plate portion formed as a plane perpendicular to the up-down direction; A cylindrical side wall portion having a lower portion fixed to the base plate portion and extending upward and downward; A vertical moving part in which the upper part of the above cylindrical side wall is fixedly joined and moves up and down; A guide support member that guides the vertical movement of the above vertical moving member; and The vertical moving part includes a vertical driving part that provides driving force for moving in the up and down direction, A gas collection device, wherein a space surrounded by the base plate portion, the cylindrical side wall portion, and the vertical moving portion is formed as the gas diffusion space.

4. In paragraph 3, A gas inlet / outlet is formed in the above base plate portion, A gas collection device in which the gas is injected or discharged into the gas diffusion space through the gas inlet or outlet.

5. In paragraph 3, A gas collection device wherein the above cylindrical side wall portion has a bellows structure.

6. In paragraph 3, The above vertical moving part, A cylindrical body member extending vertically, It includes a top plate member formed as a plane perpendicular to the up-down direction and to which the upper part of the body member is fixedly joined to the bottom surface, The upper part of the above cylindrical side wall is fixedly joined to the lower surface of the above upper plate member, The above body member is located inside the cylindrical side wall portion, A gas collection device in which the above gas diffusion space is formed as a space surrounded by the lower part of the body member, the upper surface of the base plate part, and the inner surface of the cylindrical side wall part.

7. In paragraph 6, When the above vertical moving part is lowered to the lowest point, The lower part of the above body member is in contact with the upper surface of the above base plate part, A gas collection device in which all inner surfaces of the above cylindrical side wall portion face the outer surface of the above body member.

8. In paragraph 6, The above top plate member is formed in a disk shape, The above guide support member is formed in a cylindrical shape extending in the vertical direction, The inner diameter of the above guide support member is the same as the diameter of the above top plate member, A gas collection device in which the above top plate member is guided by sliding on the inner surface of the above guide support member.

9. In paragraph 8, The lower part of the above guide support is fixed to the upper surface of the above base plate, A guide hole extending in the vertical direction is formed on the side of the above guide support member, The above vertical driving part, A power transmission member having one end inserted into the guide support member through the guide hole and the other end positioned outside the guide support member, and coupled to the upper surface of the upper plate member; A vertical moving shaft extending in the vertical direction and connected to the other end of the power transmission member, A gas collection device including a driving actuator that is supported on the base plate and moves the vertical moving shaft up and down.

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