Apparatus for thermal propagation test of secondary battery

Abstract

The present invention relates to an ignition test device for a secondary battery module. The test device has the advantage of being able to measure changes in internal pressure in real time by providing a partition separating and shielding the space where the secondary battery is mounted, together with a pressure sensor, inside a chamber that simulates a secondary battery module with a secondary battery mounted therein, and by providing means for analyzing temperature and / or gas, etc. inside the chamber, thereby enabling comprehensive acquisition of information related to the ignition of the battery module.

Description

Technology Field

[0001] The present invention relates to an ignition test device for a secondary battery module. Background Technology

[0003] Recently, rechargeable secondary batteries are being widely used as energy sources for wireless mobile devices. Furthermore, modularized devices utilizing these secondary batteries are attracting attention as energy sources for electric vehicles and hybrid electric vehicles, which are being proposed as solutions to address air pollution caused by conventional gasoline and diesel vehicles that use fossil fuels. Consequently, the types of applications using secondary batteries are becoming highly diversified due to their advantages, and it is expected that secondary batteries will be applied to a wider range of fields and products in the future than they are today.

[0004] A secondary battery is formed by housing an electrode assembly, comprising a positive electrode, a separator, and a negative electrode, within a pouch and then injecting an electrolyte into the interior. The positive and negative electrodes constituting the electrode assembly of the secondary battery are formed by applying positive and negative electrode materials onto electrode sheets. Secondary batteries require various performance characteristics tailored to the devices to which they are applied.

[0005] Generally, secondary batteries may generate gas internally as they operate in an abnormal state due to overcharging, over-discharging, overheating, or external impact. In particular, an overheated battery generates gas, and the gas pressurized within the case further accelerates the decomposition reaction of battery components, leading to continuous overheating and gas generation. This phenomenon causes changes in the internal pressure of the secondary battery, which in turn causes deformation of the battery and can lead to ignition of the battery due to an internal short circuit, as well as ignition of the module containing the battery. Therefore, to further improve the safety of battery modules at high temperatures, information regarding the type and amount of gas generated from the secondary battery at high temperatures, the resulting pressure changes within the module, and temperature changes within the secondary battery and the battery module containing it is considered important.

[0006] However, test devices developed to obtain such information only measure the type of gas generated from a secondary battery placed under overheating conditions or the temperature of the secondary battery itself at the time of ignition, so it is difficult to obtain comprehensive information about the inside of the battery module at the time of ignition, and there is a limitation in that safety is low due to frame collapse as the battery module is completely burned due to ignition during the test. Prior art literature

[0008] Republic of Korea Published Patent Application No. 10-2017-0057759 The problem to be solved

[0009] Accordingly, the objective of the present invention is to provide a device capable of comprehensively acquiring information regarding changes occurring inside a secondary battery module upon ignition, specifically changes in internal pressure, temperature, and / or gas. means of solving the problem

[0011] In order to solve the aforementioned problem,

[0012] In one embodiment of the present invention,

[0013] A chamber in which a plurality of battery pouches are mounted inside; and

[0014] It includes a partition wall positioned internally to face a battery pouch mounted in the chamber, shielding the space where the battery pouch is mounted, and movable according to changes in internal pressure of the shielded space.

[0015] The above-described partition provides an ignition test device for a secondary battery module that includes a pressure sensor on the other side of the surface facing the battery pouch.

[0016] At this time, the pressure sensor may include an elastic body that is inserted to contact the surface of the partition wall where the pressure sensor is provided and the inner surface of the chamber facing said surface, respectively, and is compressed or expanded by the movement of the partition wall.

[0017] In addition, the ignition test device may include a gas analysis unit on one inner side of the space where the battery pouch is mounted.

[0018] In addition, the above-mentioned ignition test device may include a temperature sensor on one inner side of the space where the battery pouch is mounted to measure the internal temperature of the chamber and the surface temperature of the battery pouch.

[0019] Here, the temperature sensor may have a stripe-shaped pattern structure that is horizontal to the bottom surface of the chamber.

[0020] In addition, the temperature sensor may be provided on the inner side of the space in which the battery pouch is mounted, facing the surface of the battery pouch. Among the provided temperature sensors, the temperature sensor positioned on the lower side contacts the surface of the battery pouch to measure the temperature of the battery pouch surface, while the temperature sensor positioned on the upper side does not contact the surface of the battery pouch to measure the internal temperature of the chamber.

[0021] In addition, the ignition test device may include a heating means for applying heat to the battery pouch on the inner surface of the space in which the battery pouch is mounted.

[0022] Specifically, the heating means may be positioned on the lower surface of the mounted battery pouch among the inner surfaces of the space in which the battery pouch is mounted, or on the surface facing the battery pouch.

[0023] In addition, the heating means may include one or more of a heating pad, a heating coil, and a heating cable. Effects of the invention

[0025] The ignition test device for a secondary battery module according to the present invention has the advantage of being able to measure changes in internal pressure in real time by providing a partition separating and shielding the space where the secondary battery is mounted, together with a pressure sensor, inside a chamber that simulates a secondary battery module with a secondary battery mounted therein, and by providing means for analyzing temperature and / or gas, etc. inside the chamber, thereby enabling comprehensive acquisition of information related to the ignition of the battery module. Brief explanation of the drawing

[0027] FIGS. 1 and 2 are cross-sectional views showing the structure of an ignition test device for a secondary battery module according to the present invention. FIGS. 3 and 4 are perspective views showing the structure of an ignition test device for a secondary battery module according to the present invention. Specific details for implementing the invention

[0028] The present invention is capable of various modifications and may have various embodiments, and specific embodiments are to be described in detail in the detailed description.

[0029] However, this is not intended to limit the invention to specific embodiments, and it should be understood that it includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention.

[0030] In the present invention, terms such as "comprising" or "having" are intended to specify the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not excluding in advance the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0031] Furthermore, in the present invention, when a part such as a layer, film, region, or plate is described as being "on" another part, this includes not only cases where it is "immediately above" the other part, but also cases where there is another part in between. Conversely, when a part such as a layer, film, region, or plate is described as being "under" another part, this includes not only cases where it is "immediately below" the other part, but also cases where there is another part in between. Additionally, in the present application, being "placed on" may include cases where it is placed on the lower part as well as on the upper part.

[0033] The present invention will be described in more detail below.

[0035] Ignition test device for secondary battery modules

[0036] In one embodiment of the present invention,

[0037] A chamber in which a plurality of battery pouches are mounted inside; and

[0038] It includes a partition wall positioned internally to face a battery pouch mounted in the chamber, shielding the space where the battery pouch is mounted, and movable according to changes in internal pressure of the shielded space.

[0039] The above-described partition provides an ignition test device for a secondary battery module that includes a pressure sensor on the other side of the surface facing the battery pouch.

[0041] The ignition test device for a secondary battery module according to the present invention facilitates the measurement of pressure changes that may occur inside the module by separating and shielding the space in which the secondary battery is mounted within a chamber simulating a secondary battery module with a secondary battery mounted inside, and introducing a partition wall that moves in accordance with changes in the internal pressure of the space in which the secondary battery is mounted, together with a pressure sensor. Furthermore, by providing means within the chamber to measure changes in the internal environment in real time, information related to the ignition of the battery module can be comprehensively acquired; thus, compared to conventional technologies that acquired this information individually, there is an advantage of high reliability of information within the module.

[0043] FIGS. 1 to 4 are a cross-sectional view and a perspective view showing the structure of an ignition test device for a secondary battery module according to the present invention. First, referring to FIGS. 1 and 2, the ignition test device (1) for a secondary battery module according to the present invention includes a chamber (10) in which a plurality of secondary batteries, specifically a plurality of battery pouches (2), are mounted inside. The chamber (10) functions to provide a space for simulating the interior of a battery module, and the battery pouches (2) mounted inside the chamber (10) can be provided in the same manner as they are mounted in an actual battery module.

[0044] The present invention simulates the configuration of a battery module inside a chamber (10) and applies it to an ignition test, thereby preventing the collapse of the frame structure even after ignition. Unlike conventional test devices, this eliminates the difficulty of data collection due to the complete burning of the module and offers the advantage of excellent stability. Furthermore, the ignition test device (1) can comprehensively observe changes in the battery pouch (2) upon ignition. Since the observation results reflect changes in temperature, pressure, and internal gas composition within the chamber and have a high degree of similarity to the results generated in an actual battery module, the reliability of the observation results is high.

[0046] In addition, the chamber (10) may be provided with a partition (12) inside to separate and shield the space where the battery pouch (2) is mounted, and the partition (12) may be positioned to face the battery pouch (2). The partition (12) is configured to be movable according to changes in internal pressure of the shielded space and may respond to changes in internal pressure caused by the battery pouch (2), and may include a pressure sensor (20) for measuring such changes in internal pressure.

[0047] Specifically, the above partition (12) may include a pressure sensor (20) on the other side of the surface facing the battery pouch, that is, on the surface of the space where the battery pouch is not mounted, in order to measure the degree of pressure change in the space where the battery pouch (2) is mounted.

[0048] The pressure sensor (20) may be in the form of a pad that can see the pressure distribution of the battery pouch (2), and the pressure sensor (20) in the form of a pad is placed on the other side of the surface facing the battery pouch (2) so as to measure the local pressure difference on the surface of the battery pouch (2) due to swelling phenomenon inside the battery, as well as the pressure difference between locations according to the placement of the battery pouch (2).

[0049] Additionally, as shown in FIGS. 1 and 2, the pressure sensor (20) may have a structure in which it is placed on the other side of the partition wall (12) facing the battery pouch (2), and is inserted so as to contact the surface of the partition wall (12) where the pressure sensor (20) is placed and the inner side of the chamber (10) facing the said surface. The pressure sensor (20) inserted in this manner may have a configuration including an elastic body that is compressed or expanded by the movement of the partition wall (12). Such an elastic body may include a spring, a sponge, etc., but is not limited thereto.

[0050] As an example, the pressure sensor (20) may include a pad-shaped sensor disposed on the other side of the surface facing the battery pouch (2), and may include a spring member inserted into the pad-shaped sensor to contact the inner surface of the chamber (10) facing the sensor surface.

[0051] The present invention allows for real-time measurement of the degree of compression or expansion of the elastic body by placing a pressure sensor (20) including an elastic body on the other side of the partition wall (12) facing the battery pouch (2), and allows for the calculation of the pressure change in the space where the battery pouch (2) is mounted from the measured amount of change in the elastic body. In addition, compared to pressure sensors such as conventional pressure measuring elements, it has the advantage of being able to precisely measure the pressure difference on the surface of the battery pouch caused by internal changes in the battery, such as swelling.

[0052] Additionally, the above partition (12) is positioned adjacent to the battery pouch (2) mounted inside the chamber (10) to minimize the space around the battery pouch (2). Accordingly, the above partition (12) has the advantage of being able to move more sensitively to pressure changes caused by gas generated from the battery pouch (2) when the battery pouch (2) is exposed to high temperatures or heated, and to rapid internal pressure changes when ignition occurs.

[0053] For example, the distance between the above partition (12) and the surface of the battery pouch (2) mounted inside the chamber (10) may be 5 cm or less, specifically 4 cm or less, 3 cm or less, or 2 cm or less, and in some cases, the test may be performed with the above partition (12) in contact with the surface of the battery pouch (2).

[0055] In addition, the ignition test device (1) for a secondary battery module of the present invention may include a gas analysis unit (30) on one side of the inner surface of the space where the battery pouch (2) is mounted.

[0056] Specifically, the gas analysis unit (30) is a means for analyzing gas generated from a battery pouch (2) mounted inside during ignition, and may be provided on the inner surface of the space where the battery pouch (2) is mounted, the inner surface (11, 11a and 11b) of the chamber forming the space, and / or the surface of the partition wall (12).

[0057] In addition, the gas sensor (30) may include a gas detection sensor that observes whether gas is generated from the battery pouch (2) and detects the type of gas generated.

[0058] Specifically, the gas analysis unit (30) may be equipped with a Micro-electro-mechanical Systems (MEMS) sensor, etc., capable of checking whether gas is generated and analyzing the type of gas, on the inner side of the space where the battery pouch (2) is mounted, and in some cases, may additionally be equipped with a configuration (not shown) for extracting gas inside the chamber and analyzing the type and amount of gas generated from the battery pouch (2).

[0059] As an example, the gas analysis unit (30) may include: a gas outlet provided on one inner side of a space in which a battery pouch is mounted to discharge gas generated from the battery pouch; a gas suction pump fluidly connected to the gas outlet to suck in gas generated from the battery pouch; a gas analysis module located between the gas outlet and the suction pump to analyze the components and amount of gas sucked into the suction pump; a gas supply port provided on one inner side of the space in which the battery pouch is mounted to be spaced apart from the gas outlet to supply inert gas; and a gas supply pump fluidly connected to the gas supply port to supply inert gas into the chamber.

[0060] In this case, the gas supply pump can supply gas at the same speed as the gas sucked in by the gas suction pump so as not to affect the pressure change inside the chamber (10).

[0061] In addition, the gas analysis module may include gas chromatography (GC) capable of analyzing the components and amount of gas generated.

[0063] In addition, the ignition test device (1) for the secondary battery module may include a temperature sensor (40) that measures the surface temperature of the battery pouch (2) and the temperature inside the chamber (10) on an inner surface of the space where the battery pouch (2) is mounted.

[0064] The temperature sensor (40) may be provided on an inner surface of the space in which the battery pouch (2) is mounted, that is, on an inner surface (11, 11a and 11b) of the chamber (10) forming the space, and the sensor for measuring the surface temperature of the battery pouch (2) and the sensor for measuring the temperature inside the space may have the same shape or different measurement method.

[0065] Specifically, the temperature sensor (40) is provided on one inner surface of the chamber (10) that forms the space in which the battery pouch (2) is mounted, and may be provided on the surface facing the battery pouch. Its shape is not particularly limited, but preferably, it may include a temperature sensor having a stripe-shaped pattern structure using a coin-shaped temperature sensor or a thermocouple wire.

[0066] As an example, as shown in FIG. 3, the temperature sensor may include a coin-shaped temperature sensor (41) for measuring the temperature inside the chamber and a temperature sensor (40) having a stripe-shaped pattern structure for measuring the surface temperature of the battery pouch (2), wherein the stripe-shaped temperature sensor (40) may be arranged to be horizontal with the bottom surface of the chamber.

[0067] As another example, as shown in FIG. 4, the temperature sensor is provided on an inner surface (11a) of the chamber in the form of a stripe that is horizontal to the lower surface of the chamber. Among the temperature sensors provided on the inner surface of the chamber, the temperature sensor (40a) positioned on the lower side contacts the battery pouch (2) to measure the surface temperature of the battery pouch (2), and the temperature sensor (40b) positioned on the upper side does not contact the surface of the battery pouch (2) to measure the temperature of the space in which the battery pouch (2) is mounted. In addition, in this case, the gas sensor (30) described above may be placed on an inner surface (11b) adjacent to the inner surface (11a) of the chamber where the temperature sensors (40a and 40b) are provided.

[0068] The present invention allows for real-time observation of temperature changes inside the battery pouch (2) and chamber (10) until ignition is induced after high-temperature exposure or heating of the battery pouch (2), by including a temperature sensor (40) in the device as described above, and can avoid affecting measuring means such as a gas sensor (30).

[0070] Furthermore, the ignition test device (1) for the secondary battery module may include a heating means (50) for applying heat to a battery pouch (2) mounted inside. Since the ignition test device (1) according to the present invention is intended to observe internal changes in a battery module equipped with a secondary battery under conditions where heat is applied, such as overcharging, over-discharging, overheating, or exposure to high temperature, it may include a heating means (50) for applying heat to a battery pouch (2) mounted inside.

[0071] Here, the heating means (50) may be provided on the inner surface of the space in which the battery pouch (2) is mounted, specifically on the inner surface of the chamber (10) facing the battery pouch (2); or on one surface of the partition wall (12) facing the battery pouch (2); or on the lower surface of the mounted plurality of battery pouches (2), i.e., on the lower surface of the chamber (10).

[0072] As one example, as shown in FIG. 1, the heating means (50) may be placed on one side of the partition (12) facing the battery pouch (2).

[0073] As another example, as shown in FIG. 2, the heating means (50) may be placed at the bottom of a plurality of battery pouches mounted inside the chamber.

[0074] The present invention allows heat to be applied uniformly to a plurality of battery pouches (2) by adjusting the position of the heating means (50) as described above, and allows for precise measurement of the temperature change of the battery pouches (2) over time at the time of ignition by appropriately controlling the distance from the temperature sensor.

[0075] Additionally, the heating means (50) can be applied without special limitation as long as it is in a form capable of applying heat to the battery pouch, but specifically, a heating pad, heating coil, heating cable, etc. can be used as the heating means (50) alone or in combination.

[0077] As described above, the ignition test device (1) for a secondary battery module according to the present invention simulates the configuration of a battery module inside a chamber (10) and applies it to an ignition test, so that the frame structure does not collapse even after ignition. Therefore, unlike conventional test devices, it has the advantage of easy collection of data related to the ignition of the module and excellent stability. In addition, the ignition test device (1) can comprehensively observe changes in the battery pouch (2) upon ignition, and the observation results reflect changes in temperature, pressure, and internal gas composition inside the chamber, and thus have a high degree of similarity to the results generated in an actual battery module, which has the advantage of high reliability of the observation results.

[0079] Although the present invention has been described above with reference to preferred embodiments, those skilled in the art or those with ordinary knowledge in the art will understand that various modifications and changes can be made to the present invention without departing from the spirit and technical scope of the invention as described in the claims set forth below.

[0080] Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be determined by the claims. Explanation of the symbols

[0082] 1: Ignition test device for battery modules 2: Battery pouch 10: Chamber 11, 11a, and 11b: Inner surfaces of the chamber 12: Bulkhead 20: Pressure sensor 30: Gas sensor 40 and 41: Temperature sensors 40a: Lower temperature sensor 40b: Upper temperature sensor 50: Heating means

Claims

Claim 1 A secondary battery module ignition test device comprising: a chamber in which a plurality of battery pouches are mounted; a partition disposed internally to face the battery pouches mounted in the chamber, shielding the space in which the battery pouches are mounted, and movable according to changes in internal pressure of the shielded space; and a heating means disposed on the inner side of the space in which the battery pouches are mounted and applying heat to the battery pouches, wherein the partition comprises a pressure sensor on the other side of the surface facing the battery pouches, and the pressure sensor comprises an elastic body inserted to contact each of the one side of the partition in which the pressure sensor is provided and the inner side of the chamber facing said one side, and which is compressed or expanded by the movement of the partition, and the degree of compression or expansion of the elastic body is measured to calculate changes in pressure of the space in which the battery pouches are mounted. Claim 2 delete Claim 3 In claim 1, the ignition test device is an ignition test device for a secondary battery module comprising a gas analysis unit on one inner surface of a space in which a battery pouch is mounted. Claim 4 In claim 1, the ignition test device is an ignition test device for a secondary battery module comprising a temperature sensor that measures the internal temperature of the chamber and the surface temperature of the battery pouch on one inner surface of the space in which the battery pouch is mounted. Claim 5 In paragraph 4, the temperature sensor is a ignition test device for a secondary battery module having a stripe-shaped pattern structure that is horizontal to the lower surface of the chamber. Claim 6 In claim 5, a temperature sensor is provided on the inner surface of a space in which a battery pouch is mounted, which faces the surface of the battery pouch, and among the provided temperature sensors, a temperature sensor positioned on the lower side contacts the surface of the battery pouch to measure the temperature of the battery pouch surface, and a temperature sensor positioned on the upper side does not contact the surface of the battery pouch to measure the internal temperature of the chamber, for an ignition test device for a secondary battery module. Claim 7 delete Claim 8 In claim 1, the heating means is an ignition test device for a secondary battery module disposed at the bottom of a mounted battery pouch. Claim 9 In claim 1, the heating means is an ignition test device for a secondary battery module disposed on a surface facing the battery pouch. Claim 10 In claim 1, the heating means comprises one or more of a heating pad, a heating coil, and a heating cable, for an ignition test device for a secondary battery module.

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