Secondary battery and secondary battery module including gas adsorbing material

Abstract

The present invention relates to a secondary battery and a module including the same. The secondary battery has a gas adsorption material coated on the inner surface of a case, which adsorbs internal gas at a normal operating temperature based on a critical temperature and desorbs the adsorbed internal gas at a high temperature. When exposed to an abnormally high temperature, the internal pressure can reach a critical point in a short time, accelerating the time point at which the internal gas is released, thereby further improving the thermal propagation and fire safety of the battery. In addition, the secondary battery has an excellent effect of absorbing gas generated within the normal operating temperature range, reducing the pressure inside the battery case, suppressing deformation of the battery case, and not deteriorating battery performance.

Description

[Technical field]

[0001] The present invention relates to a secondary battery in which the inner surface of a battery case is coated with a material that adsorbs and desorbs gas depending on temperature conditions, and a secondary battery module including the same.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2021-0157299 dated November 16, 2021, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference. [Background technology]

[0003] Recently, with the increase in technological development and demand for mobile devices and the popularization of electric vehicles (EVs), the demand for batteries as an energy source has increased dramatically. As a result, much research is being conducted on batteries that can meet various needs.

[0004] Typically, from the viewpoint of battery shape, there is a high demand for prismatic secondary batteries and pouch-type secondary batteries which are thin and applicable to products such as mobile phones, and from the viewpoint of materials, there is a high demand for lithium secondary batteries such as lithium ion batteries and lithium ion polymer batteries which have advantages such as high energy density, discharge voltage, and output stability.

[0005] However, despite these advantages, lithium secondary batteries have safety shortcomings. Specifically, the electrolyte reacts to generate gas during the primary charge immediately after injecting the electrolyte into the battery assembly, aging, and charge / discharge. The generated gas is trapped inside the battery, causing problems such as capacity reduction and lithium precipitation.

[0006] In addition, when a large amount of gas is generated, the pressure in the dead space between the case and the electrode assembly increases, making it difficult for the gas trapped inside the electrode assembly to be discharged to the dead space, and the trapped gas may deteriorate the battery performance.Furthermore, the increase in the internal pressure of the battery may induce deformation of the cylindrical or rectangular battery case, which may cause serious problems such as an explosion of the secondary battery.

[0007] In order to solve the above problems, gas exhaust means for exhausting gas generated inside the secondary battery case to the outside and reducing the internal pressure is generally formed in the case. However, since the gas exhaust means ruptures at a relatively high critical temperature and the pressure inside the battery increases slowly, when the temperature of one of the multiple individual secondary batteries in the secondary battery module increases abnormally, heat is transmitted to the adjacent individual secondary batteries, and the gas exhaust means of the normal individual secondary batteries are also ruptured in a chain reaction, causing the batteries to stop operating or to deteriorate in performance. Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a secondary battery and a module including the same that can adsorb gas inside the battery at normal operating temperatures, and when an abnormal temperature rise occurs in the secondary battery, can quickly discharge gas and increase the internal pressure to quickly reach a pressure critical point and discharge gas to the outside of the case.

[0009] Another object of the present invention is to provide a secondary battery that adsorbs gas generated within the normal operating temperature range of a secondary battery, reduces the pressure inside the battery case, suppresses deformation of the battery case, and does not deteriorate battery performance. [Means for solving the problem]

[0010] To solve the above problem, In one embodiment, the present invention comprises: An electrode assembly; a case in which the electrode assembly is housed, The case provides a secondary battery having a coating layer on the inside surface thereof, the coating layer containing a gas adsorbing material that adsorbs or desorbs internal gas depending on the temperature inside the case.

[0011] At this time, the gas adsorbent has a critical temperature of 70 to 150° C., and can adsorb the internal gas below the critical temperature and desorb the internal gas above the critical temperature.

[0012] Such gas adsorbent materials may include diamine compounds containing one or more metals selected from the group consisting of magnesium, manganese, iron, zinc, and cobalt, and the diamine compounds may include one or more of mmen-Mg2(dobpdc), mmen-Mn2(dobpdc), mmen-Fe2(dobpdc), mmen-Zn2(dobpdc), and mmen-Co2(dobpdc).

[0013] The gas adsorbent material may also include one or more of carbon fiber, activated carbon, zeolite, alumina, silica, bauxite, and molecular sieves.

[0014] The coating layer may include a first gas adsorption substance having a critical temperature of 70 to 110° C., a second gas adsorption substance having a critical temperature of 110 to 140° C., and a binder.

[0015] The first gas adsorption substance and the second gas adsorption substance may be contained in an amount of 60 to 80% by weight and 19 to 50% by weight, respectively, based on the total weight of the coating layer.

[0016] The coating layer may have an average thickness of 50 μm to 500 μm.

[0017] The coating layer may have a pattern structure with an area ratio of 50 to 90% based on the total area of ​​the case.

[0018] The internal gas may also include one or more of oxygen (O2), hydrogen (H2), ethylene (C2H4), acetylene (C2H2), propylene (C3H6), carbon monoxide (CO), carbon dioxide (CO2), methane (CH4), ethane (CH3CH3), propane (CH3CH2CH3), nitric oxide (NO), and nitrogen dioxide (NO2).

[0019] The secondary battery may further include a gas exhaust means that is vented by pressure.

[0020] In one embodiment, the present invention provides a method for producing a composition comprising: There is provided a secondary battery module including the secondary battery according to the present invention as described above. Effect of the Invention

[0021] The secondary battery according to the present invention has a gas adsorption material coated on the inner surface of the case, which adsorbs internal gas at normal operating temperature based on the critical temperature and desorbs the adsorbed internal gas at high temperature. When exposed to abnormally high temperatures, the internal pressure can reach the critical point in a short time, accelerating the time point at which the internal gas is released, thereby further improving the heat propagation and fire safety of the battery.

[0022] In addition, the secondary battery is excellent in the effect of absorbing gas generated within the normal operating temperature range to reduce the pressure inside the battery case, suppressing deformation of the battery case, and preventing deterioration of battery performance. [Brief description of the drawings]

[0023] [Figure 1] 1 is a cross-sectional view showing a structure of a pouch-type secondary battery according to an embodiment of the present invention. [Diagram 2] FIG. 4 is a cross-sectional view showing a structure of a pouch-type secondary battery according to another embodiment of the present invention. [Diagram 3] Graph (a) shows the CO2 adsorption isotherm of a typical CO2 adsorbent, and graph (b) shows the CO2 adsorption isotherm of the mmen-M2 (dobpdc) adsorbent. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described with reference to the drawings according to the embodiments of the present invention. However, this is for easier understanding of the present invention, and the scope of the present invention is not limited thereby.

[0025] <Secondary battery> In one embodiment, the present invention comprises: An electrode assembly; a case in which the electrode assembly is housed, The case provides a secondary battery having a coating layer on the inside surface thereof, the coating layer containing a gas adsorbing material that adsorbs or desorbs internal gas depending on the temperature inside the case.

[0026] The secondary battery according to the present invention includes an electrode assembly, and the electrode assembly is housed in a case. The case may be of various shapes depending on the shape, structure, and manufacturing method of the secondary battery, and may be of a cylindrical shape, a square shape, a pouch shape, etc. For example, the case may be a pouch-type case.

[0027] In addition, the case may be provided with a coating layer containing a gas adsorption material that adsorbs or desorbs internal gas generated during charging and discharging of the secondary battery on an inner surface thereof. Specifically, the case may include a coating layer in the form of a mixture of the gas adsorption material and a binder that fixes the gas adsorption material on an inner surface where the electrode assembly is disposed.

[0028] At this time, the gas adsorbent contained in the coating layer has a critical temperature of 70 to 150° C., and can adsorb the internal gas below the critical temperature and desorb the internal gas above the critical temperature. That is, the gas adsorbent adsorbs the internal gas generated by charging and discharging the battery at a normal operating temperature below the critical temperature, thereby reducing the pressure inside the case, and when heat is generated above the critical temperature due to abnormal operation of the battery, the gas adsorbent desorbs the adsorbed gas and increases the gas pressure inside the case in a short time or instantaneously, thereby quickly venting the internal gas before thermal runaway.

[0029] For this reason, the gas adsorbent may have a critical temperature of 70 to 150° C., specifically, 70 to 130° C., 70 to 110° C., 70 to 90° C., 90 to 120° C., 100 to 110° C., 110 to 125° C., or 120 to 140° C. By adjusting the critical temperature of the gas adsorbent within the above range, the present invention is able to adsorb the internal gas at the normal operating temperature of the battery and effectively desorb the gas at an abnormal operating temperature, for example, under exothermic conditions, thereby increasing the internal pressure within a short period of time or instantaneously.

[0030] Such a gas adsorption material can be applied without any particular limitation so long as it adsorbs or desorbs gas based on a critical temperature of 70 to 150°C. Specifically, it may include a diamine compound containing one or more metals selected from magnesium, manganese, iron, zinc, and cobalt. In addition to the diamine compound, a material having a porous structure that captures gas, such as carbon fiber, activated carbon, zeolite, alumina, silica, bauxite, and molecular sieves, may be used alone or in combination.

[0031] As an example, the gas adsorption material may include a diamine compound having a critical temperature of 70 to 90°C, the diamine compound including one or more of mmen-Mg2(dobpdc), mmen-Mn2(dobpdc), mmen-Fe2(dobpdc), mmen-Zn2(dobpdc) and mmen-Co2(dobpdc), where "mmen" means N,N-dimethylethylenediamine and "Dobpdc" means 4,4'-dioxidobiphenyl-3,3'-dicarboxylate.

[0032] The diamine compound is an amine compound that does not coordinate with the mmen molecule, and acts as a strong base to remove acidic protons from the metal-bound amines of the adjacent mmen molecules, causing a phase transition in which a carbamate with an ammonium counter cation is formed when gas (e.g., CO2) is adsorbed. When appropriate temperature and pressure are applied, the MN bond breaks, allowing the carbamate to rearrange to form an MO bond. The ion-pairing interaction stretches the mmen molecule, destabilizing the MN bond and promoting the insertion of gas (e.g., CO2) at the next metal site. This cooperative effect propagates until a complete one-dimensional ammonium carbamate chain is formed, and a large amount of gas (e.g., CO2) is adsorbed due to this cooperative effect, resulting in a steep vertical adsorption isotherm.

[0033] In contrast, when the gas (e.g., CO2) was adsorbed on mmen-M2(dobpdc) at higher temperatures and pressures (T in Figure 3), medium or T high Temperature and P des When a pressure of 10 ...

[0034] On the one hand, in mmen-M2(dobpdc), the metal-amine bond strength varies depending on the type of divalent metal M. Therefore, the positions of the gas adsorption stage and the gas desorption stage change. However, at a given same temperature, the positions of the gas adsorption stage and the desorption stage change in the order of Mg < Mn < Fe < Zn < Co. That is, when the above mmen-M2(dobpdc) is lower than the critical temperature, it absorbs internal gas, and when it is higher than the critical temperature, it releases internal gas. By appropriately selecting the above M, the critical temperature at which the adsorption and desorption of internal gas are converted can be adjusted.

[0035] The present invention uses the gas (such as CO2) adsorption and desorption characteristics of mmen-M2(dobpdc) as described above. Internal gases such as CO2 generated during the normal charge and discharge process of a secondary battery can increase the adsorption rate using the gas adsorption substance of the above mmen-M2(dobpdc). When an abnormal reaction such as a temperature rise due to a short circuit of the secondary battery occurs, the internal gas adsorbed in the gas adsorption substance is rapidly desorbed at a temperature above the critical temperature, and the internal pressure of the secondary battery case is rapidly increased, thereby rupturing the rupture member of the gas discharge means to discharge the gas. Thereby, the secondary battery in which an abnormal reaction has occurred in the secondary battery module can be quickly disabled, and the chain-like heat propagation to adjacent secondary batteries can be prevented.

[0036] As another example, the gas adsorption substance may be zeolite, activated alumina, and / or silica gel having a critical temperature of 110 to 140°C. The zeolite, activated alumina, and / or silica gel may have the same chemical composition, but their critical temperatures vary depending on post-treatment processes such as heat treatment, surface treatment, and surface coating, process conditions during manufacturing, and doping in the material. The critical temperature can be appropriately adjusted according to the internal temperature range predicted by the conditions under which the secondary battery is driven.

[0037] The coating layer may contain a gas adsorption material and may contain two or more gas adsorption materials with different critical temperatures. When the coating layer contains two or more gas adsorption materials with different critical temperatures, the temperature at which the internal gas is released can be easily controlled to a desired range.

[0038] Specifically, the coating layer may include a first gas adsorption substance having a critical temperature of 70 to 110° C., a second gas adsorption substance having a critical temperature of 110 to 140° C., and a binder.

[0039] As an example, the coating layer may include a first gas adsorption material having a critical temperature of 80 to 95° C., a second gas adsorption material having a critical temperature of 115 to 130° C., and a binder.

[0040] As another example, the coating layer may include a first gas adsorption material having a critical temperature of 100 to 110° C., a second gas adsorption material having a critical temperature of 110 to 120° C., and a binder.

[0041] In this case, the first gas adsorption material adsorbs gas generated during normal operation of the secondary battery and / or when the internal temperature is below the critical temperature, thereby reducing the pressure inside the secondary battery, and when the internal temperature exceeds the critical temperature, specifically, 70 to 110°C, due to abnormal operation of the secondary battery, the first gas adsorption material desorbs the adsorbed gas, thereby significantly increasing the internal pressure.

[0042] In addition, since the second gas adsorption material has a higher critical temperature than the first gas adsorption material, when the internal temperature of the secondary battery exceeds the critical temperature of the first gas adsorption material due to abnormal operation of the secondary battery, the second gas adsorption material can adsorb a portion of the gas desorbed from the first gas adsorption material to prevent damage to the electrode assembly accommodated inside the secondary battery, and can desorb the adsorbed gas before heat transfer occurs to the secondary battery adjacent to the secondary battery inside the secondary battery, thereby increasing the pressure inside the secondary battery in a short period of time or instantaneously. For this purpose, the first gas adsorption material may have a critical temperature lower than the temperature at which heat transfer occurs in the secondary battery.

[0043] The first gas adsorption material and the second gas adsorption material may be contained in the coating layer at a certain weight ratio. Specifically, the coating layer of the present invention may contain the first gas adsorption material and the second gas adsorption material at 60 to 80 wt % and 19 to 50 wt % of the total weight, respectively, more specifically, 65 to 75 wt % and 24 to 40 wt %, or 62 to 70 wt % and 29 to 35 wt %, respectively, of the total weight.

[0044] By adjusting the contents of the first gas adsorption material and the second gas adsorption material contained in the coating layer within the above ranges, the present invention can maintain the internal pressure of the battery low at the normal operating temperature of the battery, and when the internal temperature exceeds 120°C due to abnormal operation of the battery, more specifically, at a temperature of 140°C or higher, the internal gas can be desorbed to instantaneously increase the internal pressure before thermal runaway of the battery. Therefore, the internal gas can be released to the outside of the case under lower temperature conditions, thereby further improving the safety of the battery.

[0045] The coating layer may be formed on the inner surface of the case and on the entire surface of the inner surface of the case to surround the electrode assembly housed in the case, and may have a pattern structure in order to increase the surface area. The coating layer may be formed on the entire surface of the inner surface of the case to surround the electrode assembly in order to adsorb gas generated by side reactions between active materials of the electrode assembly and / or between the active materials and the electrolyte during charging and discharging of the battery, and may be formed on the entire surface of the inner surface of the case and on the entire surface of the inner surface of the case and on the entire surface of the inner surface of the case to have a pattern structure, thereby increasing the surface area and more efficiently adsorbing gas inside the battery.

[0046] Here, when the coating layer has a pattern structure, the coating layer may be formed with an area ratio of 50 to 90% based on the total area of ​​the case, specifically, with an area ratio of 60 to 90%, 70 to 90%, 75 to 90%, or 70 to 85% based on the total area of ​​the case.

[0047] The coating layer may have an average thickness of 50 μm to 500 μm, specifically, 50 μm to 400 μm, 50 μm to 300 μm, 50 μm to 200 μm, 100 μm to 300 μm, 150 μm to 300 μm, or 80 μm to 150 μm.

[0048] In the present invention, by adjusting the area ratio and average thickness of the coating layer within the above range, it is possible to prevent a decrease in the energy density of the battery and maximize the gas adsorption rate.

[0049] Meanwhile, the internal gas generated inside the battery during charging and discharging of the secondary battery is derived from decomposition of the positive electrode, negative electrode and / or separator constituting the electrode assembly, or from decomposition of the electrolyte, and the type of the internal gas is not particularly limited.

[0050] Specifically, the internal gas may include one or more of oxygen (O2), hydrogen (H2), ethylene (C2H4), acetylene (C2H2), propylene (C3H6), carbon monoxide (CO), carbon dioxide (CO2), methane (CH4), ethane (CH3CH3), propane (CH3CH2CH3), nitric oxide (NO), and nitrogen dioxide (NO2).

[0051] As an example, the internal gas may be carbon monoxide (CO) and / or carbon dioxide (CO2). When heat is generated due to abnormal operation during charging and discharging of the battery, the electrolyte is decomposed and a considerable amount of carbon monoxide (CO) and / or carbon dioxide (CO2) is generated. The present invention can effectively control the internal pressure caused by the gas by adsorbing and desorbing such carbon monoxide (CO) and / or carbon dioxide (CO2) at a high rate.

[0052] In addition, the secondary battery according to the present invention may further include a gas exhaust means for exhausting gas to a case in which the electrode assembly is housed.

[0053] 1 and 2 are cross-sectional views showing the structure of a secondary battery according to the present invention. The structure of the secondary battery according to the present invention comprises an electrode lead 10 and a case 12 that receives an electrode assembly 14, and the electrode lead 10 is connected to the case 12 by a sealing portion 15, and a portion of the electrode lead 10 is exposed to the outside of the case 12.

[0054] Here, the case 12 may further include a gas exhaust means 11 for venting the internal gas caused by the increased internal pressure when the internal pressure is suddenly increased due to the desorption of the internal gas from the coating layer 16 caused by the abnormal operation of the battery.

[0055] Specifically, the gas exhaust means 11 may be formed on one side of the case 12 as shown in FIG. 1, or may be formed between the electrode lead 10 and the electrode tap 10' as shown in FIG. 2. During charging and discharging of the secondary battery, due to temperature rise caused by abnormal heat generation, internal gases such as CO, CO2, etc. may be generated in the secondary battery, and this may cause safety problems such as deformation of the case or fire due to an increase in the internal pressure of the secondary battery case 12. The gas exhaust means 11 is intended to solve the above problems and is not particularly limited in shape, but may include an opening (not shown) connecting the inside and outside of the secondary battery case and a rupture part (not shown) that seals the inside of the secondary battery case and ruptures when the internal pressure of the secondary battery case increases.

[0056] Furthermore, the secondary battery according to an embodiment of the present invention may include a current interrupting member. The current interrupting member may be a fuse that generates a short circuit when the temperature rises, and may be formed in a structure that breaks due to increased pressure caused by the generation of internal gas. Since the present invention utilizes the rapid desorption of internal gas from a gas adsorbing material, the current interrupting member is preferably structured to break due to pressure to interrupt the current.

[0057] That is, in the secondary battery according to the present invention, when the temperature rises due to abnormal heat generation within the battery, the gas adsorbed in the gas adsorption material is desorbed, and as a result, when a pressure above a certain level is generated inside the secondary battery case 12, the gas exhaust means 11 is vented to exhaust activated gas, gas generated during charging and discharging of the battery, and / or gas generated due to exposure of the battery to high temperatures, and the secondary battery stops operating due to the current interrupting member 13.

[0058] <Secondary battery module> The present invention also provides a secondary battery module including the above-mentioned secondary battery according to the present invention.

[0059] The secondary battery module according to the present invention includes a secondary battery according to the present invention, which includes a coating layer on an inner surface of a case, the coating layer containing a gas adsorbing material that adsorbs or desorbs gas based on a critical temperature.

[0060] As a result, the secondary battery module adsorbs internal gas at the normal operating temperature of the battery, and when the battery generates heat due to abnormal operation, it desorbs the adsorbed internal gas and allows the internal pressure (i.e., internal pressure) of the battery to reach a critical point in a short period of time, thereby easily controlling the time when the internal gas is released, which has the advantage of being highly safe.

[0061] The secondary battery module according to the present invention has excellent safety when exposed to high temperatures due to the configuration including the secondary battery of the present invention. Therefore, it can be used as a power source for medium-sized and large-sized devices that require high-temperature safety, long cycle characteristics, and high rate characteristics. Specific examples of such medium-sized and large-sized devices include power tools powered by electric motors, electric vehicles including electric vehicles (EV), hybrid electric vehicles (HEV), and plug-in hybrid electric vehicles (PHEV), electric bicycles (E-bikes), electric two-wheeled vehicles including electric scooters, electric golf carts, and power storage systems, and more specifically, hybrid electric vehicles (HEV) are included, but are not limited thereto.

[0062] The present invention will now be described in more detail with reference to examples and experimental examples. However, the following examples and experimental examples are merely illustrative of the present invention, and the content of the present invention is not limited to the following examples and experimental examples.

[0063] (Examples 1 to 4. Production of secondary batteries) An electrode assembly including a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode was prepared, and the prepared assembly was inserted into a pouch-type case, and an electrolyte was injected and then sealed to prepare a secondary battery.

[0064] The case used had a gas exhaust means on one side and a coating layer (average thickness: about 50 μm) on the inside surface as shown in Figure 1. The coating layer contained 97% by weight of gas adsorption material and 3% by weight of binder, and the first gas adsorption material (critical temperature: about 75-80°C), the second gas adsorption material (critical temperature: about 125-130°C) and the area ratio were adjusted as shown in Table 1 below.

[0065] [Table 1]

[0066] (Comparative Example 1. Manufacture of secondary battery) A secondary battery was fabricated in the same manner as in Example 1, except that a case without a coating layer formed on the inner surface was used.

[0067] (Experimental Example) The secondary batteries manufactured in the examples and comparative examples were overcharged, and the time it took for the internal gas to be discharged (i.e., vented) through the gas exhaust means of each secondary battery and the internal temperature of the secondary battery when the internal gas was discharged were measured.

[0068] Specifically, a temperature sensor was installed inside the secondary batteries manufactured in the examples and comparative examples, and the batteries were charged to 4.2 V, and then overcharged to 10 V at a constant current of 0.05 C. During the overcharge process, the internal temperature of the batteries was measured when the gas exhaust means exhausted the internal gas. The results are shown in Table 2 below.

[0069] [Table 2]

[0070] As shown in Table 2, the secondary battery according to the present invention has improved safety by having a coating layer containing a gas adsorbent material that adsorbs and desorbs internal gases depending on a critical temperature on the inner surface of the case.

[0071] Specifically, in the secondary battery of the embodiment, a coating layer containing a gas adsorption material is formed on the inner surface of the case, and when the battery is exposed to high temperatures due to abnormal operation, the internal pressure of the battery can be easily controlled, and thus the internal gas can be released before thermal runaway of the battery is induced.

[0072] On the other hand, it was confirmed that the secondary battery of the comparative example, in which no coating layer was formed, vented after thermal runaway of the battery.

[0073] From these results, it can be seen that the secondary battery according to the present invention can further improve the thermal propagation and fire safety of the battery by coating the inner surface of the case with a gas adsorbing material that adsorbs internal gas at normal operating temperature based on the critical temperature and desorbs the adsorbed internal gas at high temperatures.

[0074] Although the present invention has been described above with reference to preferred embodiments, it will be understood that a person skilled in the art or having ordinary knowledge in the art can make various modifications and changes to the present invention without departing from the spirit and technical scope of the present invention as described in the claims below.

[0075] 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 defined by the claims.

Claims

1. An electrode assembly; a case in which the electrode assembly is housed, the case has a coating layer on an inner surface thereof, the coating layer containing a gas adsorbent material that adsorbs or desorbs an internal gas depending on a temperature inside the case; The gas adsorbent has a critical temperature of 70 to 150° C., adsorbs the internal gas below the critical temperature, and desorbs the internal gas above the critical temperature; The gas adsorbent material includes mmen-M 2 (dobpdc) (mmen is N,N-dimethylethylenediamine, dobpdc is 4,4′-dioxidobiphenyl-3,3′-dicarboxylate, and M is a divalent metal); Secondary battery.

2. 2. The secondary battery according to claim 1, wherein the gas adsorbing material comprises a diamine compound containing one or more metals selected from the group consisting of magnesium, manganese, iron, zinc, and cobalt.

3. The diamine compound is mmen-Mg ２ (dobpdc), mmen-Mn ２ (dobpdc), mmen-Fe ２ (dobpdc), mmen-Zn ２ (dobpdc) and mmen-Co ２ The secondary battery according to claim 2 , comprising one or more of the following:

4. 2. The secondary battery according to claim 1, wherein the gas adsorption material comprises one or more of carbon fiber, activated carbon, zeolite, alumina, silica, bauxite, and molecular sieve.

5. The coating layer is a first gas adsorbent material having a critical temperature of 70 to 110° C.; a second gas adsorbing material having a critical temperature of 110-140° C.; a binder; The first gas adsorbent material comprises mmen-M 2 (dobpdc) (mmen is N,N-dimethylethylenediamine, dobpdc is 4,4′-dioxidobiphenyl-3,3′-dicarboxylate, and M is a divalent metal); The secondary battery according to claim 1 .

6. 6. The secondary battery according to claim 5, wherein the first gas adsorption material and the second gas adsorption material are contained in an amount of 60 to 80% by weight and 19 to 50% by weight, respectively, based on the total weight of the coating layer.

7. The secondary battery according to claim 1 , wherein the coating layer has an average thickness of 50 μm to 500 μm.

8. The secondary battery of claim 1, wherein the coating layer has a pattern structure having an area ratio of 50 to 90% based on the total area of ​​the case.

9. The internal gas is oxygen (O ２ ), hydrogen (H ２ ), ethylene (C ２ H ４ ), acetylene (C ２ H ２ ), propylene (C ３ H ６ ), carbon monoxide (CO), carbon dioxide (CO ２ ), methane (CH ４ ), ethane (CH ３ CH ３ ), propane (CH ３ CH ２ CH ３ ), nitric oxide (NO) and nitrogen dioxide (NO ２ 2. The secondary battery according to claim 1 , comprising one or more of the following:

10. The secondary battery according to claim 1 , further comprising a gas exhaust means for venting by pressure.

11. A secondary battery module comprising the secondary battery according to claim 1 .

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