Battery cells, battery modules, battery packs, and automobiles including them

Abstract

Provided are battery cells, battery modules, battery packs and vehicles configured to direct the exhaust of vent gas in a desired direction in the event of a thermal event. A battery cell according to one aspect of the present invention includes an electrode assembly, an electrode lead connected to the electrode assembly, a cell case configured to house the electrode assembly therein and support the electrode lead, and a vent induction portion provided in the cell case and configured to induce the discharge of vent gas to a certain region of the cell case as internal pressure of the cell case increases.

Description

Technical Field

[0001] The present invention relates to a battery cell, a battery module, a battery pack, and an automobile including the same, and more particularly, to a battery cell, a battery module, a battery pack, and an automobile including the same with enhanced stability.

[0002] This application claims priority based on Korean Patent Application No. 10-2021-0187854 filed on December 24, 2021 and Korean Patent Application No. 10-2022-0053129 filed on April 28, 2022, and all the contents disclosed in the specifications and drawings of the applications are incorporated into this application.

Background Art

[0003] Recently, the demand for portable electronic products such as notebook PCs, video cameras, and mobile phones has increased rapidly. Also, as the development of electric vehicles, energy storage batteries, robots, satellites, etc. has become full-scale, research on high-performance batteries capable of repeated charging and discharging has been actively underway.

[0004] Currently, commercially available batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, lithium secondary batteries, etc. Among these, lithium secondary batteries have attracted attention because they have almost no memory effect compared to nickel-based secondary batteries, can be charged and discharged freely, have a very low self-discharge rate, and have a high energy density.

[0005] Such lithium secondary batteries mainly use lithium-based oxides and carbon materials as the positive electrode active material and the negative electrode active material, respectively. A lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate coated with such positive electrode active material and negative electrode active material are arranged with a separator interposed therebetween, and an exterior material for sealing and housing the electrode assembly together with an electrolytic solution.

[0006] Lithium-ion batteries can be further classified into two types based on the shape of the battery case: can-type batteries, in which the electrode assembly is housed in a metal can, and pouch-type batteries, in which the electrode assembly is housed in an aluminum laminate sheet pouch. Can-type batteries can be further classified into cylindrical batteries and prismatic batteries based on the shape of the metal can.

[0007] Here, the pouch of a pouch-type secondary battery can be broadly divided into a lower sheet and an upper sheet that covers it. In this case, an electrode assembly formed by stacking and winding a positive electrode, a negative electrode, and a separator is housed in the pouch. After housing the electrode assembly, the periphery of the upper sheet and the lower sheet is sealed by heat welding or the like. In addition, electrode tabs drawn out from each electrode are connected to electrode leads, and an insulating film may be added to the part of the electrode lead that comes into contact with the sealed part.

[0008] Thus, pouch-type rechargeable batteries can be easily configured into a variety of forms. Furthermore, pouch-type rechargeable batteries have the advantage of being able to realize the same capacity with a smaller volume and mass.

[0009] The aforementioned lithium secondary battery is constructed by stacking or arranging multiple battery cells, either individually or mounted in cartridges, to create a dense structure that provides high voltage and high current. These are then electrically connected and used as a battery module or battery pack.

[0010] One of the most important issues in such battery pack configurations is safety. In particular, if a thermal event occurs in any one of the battery cells contained in the battery pack, the propagation of such an event to the other battery cells must be suppressed. If thermal propagation between battery cells is not properly suppressed, it can lead to thermal events in the other battery cells contained in the battery pack, potentially causing larger problems such as the battery pack catching fire or exploding. Furthermore, a fire or explosion in a battery pack can cause damage to human life and property. Therefore, in the case of battery packs, a configuration that can appropriately control the aforementioned thermal events is required. [Overview of the Initiative] [Problems that the invention aims to solve]

[0011] The present invention aims to provide battery cells, battery modules, battery packs, and automobiles configured to guide the discharge of vent gas in a desired direction when a thermal event occurs.

[0012] However, the technical problems that the present invention aims to solve are not limited to those described above, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention below. [Means for solving the problem]

[0013] A battery cell according to one aspect of the present invention for achieving the above objectives includes an electrode assembly, electrode leads connected to the electrode assembly, a cell case configured to house the electrode assembly and support the electrode leads, and a vent guide section provided in the cell case, configured to guide the discharge of vent gas to a certain area of ​​the cell case as the internal pressure of the cell case increases.

[0014] Preferably, the vent guide portion may include a material that hardens due to heat conduction caused by an increase in the internal temperature of the cell case.

[0015] Preferably, the vent guide portion is coupled to a portion of the surface of the cell case, and as the internal pressure of the cell case increases, it can guide the vent passage through which the vent gas is discharged to form in a portion of the cell case other than the portion to which the vent guide portion is coupled.

[0016] Preferably, the cell case includes a housing portion for housing the electrode assembly inside, and a sealing portion having a shape that extends a certain length from the housing portion, and the vent guide portion may be provided in a case terrace which is located in the area of ​​the entire sealing portion where the electrode leads are drawn out.

[0017] Preferably, the vent guide portion may be coupled to the portion of the case terrace where the electrode leads are located.

[0018] Preferably, the vent guide portion may be configured to be coupled to one side of the case terrace and the other side of the case terrace in the cell case.

[0019] Preferably, the vent guide portion may be configured to surround a portion of the lead film interposed between the electrode lead and the case terrace.

[0020] Preferably, the vent guide portion may be configured to surround a portion of the electrode lead.

[0021] Preferably, the vent guide portion can guide the vent passage through which the vent gas is discharged to form in a portion of the case terrace other than the portion to which the vent guide portion is connected, as the internal pressure of the cell case increases.

[0022] Preferably, as the internal pressure of the cell case increases, the vent guiding portion can guide the vent flow path to be formed at a corner portion of the case terrace.

[0023] Preferably, the case terrace may have a shape in which at least a part of the corner portion at the corner portion is chamfered.

[0024] Preferably, the case terrace may be configured to have a shape in which a corner portion located below the electrode lead is chamfered.

[0025] Preferably, the vent guiding portion may include a first vent guiding portion coupled to a case terrace located on one side in the longitudinal direction of the battery cell, and a second vent guiding portion coupled to a case terrace located on the other side in the longitudinal direction of the battery cell.

[0026] Preferably, the vent guiding portion may further include a third vent guiding portion coupled to a portion connecting between a case terrace located on one side in the longitudinal direction of the battery cell and a case terrace located on the other side in the longitudinal direction of the battery cell in the sealing portion.

[0027] Also, a battery module according to an aspect of the present invention includes at least one battery cell according to an aspect of the present invention as described above.

[0028] Also, a battery pack according to an aspect of the present invention includes at least one battery module according to an aspect of the present invention as described above.

[0029] Also, an automobile according to an aspect of the present invention includes at least one battery pack according to an aspect of the present invention as described above.

Advantages of the Invention

[0030] According to an embodiment of the present invention, the possibility of ignition inside the battery cell is reduced, so that the structural stability of the battery cell can be enhanced.

[0031] Furthermore, since the vent gas is discharged in parts of the cell case other than the weak point where the vent guide is connected, it is possible to discharge the vent gas in the intended direction.

[0032] Furthermore, various embodiments of the present invention can achieve other additional effects. These various effects of the present invention will be described in detail in each embodiment, and effects that are easily understood by those skilled in the art will not be described.

[0033] The following drawings accompanying this specification illustrate preferred embodiments of the invention and, together with the detailed description of the invention, serve to further illustrate the technical idea of ​​the invention. Therefore, the invention should not be construed as being limited solely to what is shown in the drawings. [Brief explanation of the drawing]

[0034] [Figure 1] This figure shows a battery cell according to one embodiment of the present invention. [Figure 2] Figure 1 is a front view of the battery cell. [Figure 3] This figure shows the detailed structure of the battery cell in Figure 1. [Figure 4] This diagram illustrates the venting process when thermal runaway occurs in the battery cell shown in Figure 1. [Figure 5] This diagram illustrates the venting process when thermal runaway occurs in a conventional battery cell. [Figure 6] Figure 5 is a diagram illustrating the voltage and temperature changes over time. [Figure 7] This figure shows a battery cell according to another embodiment of the present invention. [Figure 8] This figure shows a battery cell according to yet another embodiment of the present invention. [Figure 9] This figure shows a battery cell according to yet another embodiment of the present invention. [Figure 10]This figure shows a battery module including the battery cell of the present invention. [Figure 11] Figure 9 shows a battery pack including the battery module. [Figure 12] Figure 10 shows a car including a battery pack. [Modes for carrying out the invention]

[0035] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. Prior to this, terms and words used in this specification and in the claims should not be interpreted in a manner limited to their ordinary or dictionary meanings, but rather in a manner and concept that is in line with the technical idea of ​​the present invention, in accordance with the principle that the inventor himself can appropriately define the concepts of terms in order to best describe the invention.

[0036] Therefore, it should be understood that the embodiments and configurations shown in the drawings described herein represent only one of the most preferred embodiments of the present invention and do not represent the entirety of the technical concept of the present invention, and that there are various equivalents and modifications that can be substituted for them at the time of this application.

[0037] Figure 1 shows a battery cell 10 according to one embodiment of the present invention, Figure 2 is a front view of the battery cell 10 of Figure 1, and Figure 3 shows the detailed structure of the battery cell 10 of Figure 1. In this case, Figure 3 is a bottom view of the battery cell 10 of Figure 1, obtained by cross-sectional processing with respect to the XY plane with respect to the line B-B' as the reference.

[0038] In embodiments of the present invention, the X-axis direction shown in the drawings may refer to the longitudinal direction of the battery cell 10, the Y-axis direction may refer to the front-to-back direction of the battery cell 10 perpendicular to the X-axis direction in the horizontal plane (XY plane), and the Z-axis direction may refer to the up-and-down direction perpendicular to both the X-axis and Y-axis directions.

[0039] Referring to Figures 1 to 3, a battery cell 10 according to one embodiment of the present invention may include an electrode assembly 100, electrode leads 200, a cell case 300, and a vent guide section 400.

[0040] The aforementioned battery cell 10 may mean a secondary battery. Such a battery cell 10 may be a pouch-type battery cell.

[0041] The electrode assembly 100, although not shown in detail, may include a first electrode plate having a first polarity, a second electrode plate having a second polarity, and a separation membrane interposed between the first and second electrode plates. For example, the first electrode plate may be a positive or negative electrode plate, and the second electrode plate may be an electrode plate having the opposite polarity to the first electrode plate.

[0042] The electrode lead 200 can be electrically connected to the electrode assembly 100. Such an electrode lead 200 may be connected to only one side of the electrode assembly 100 in the longitudinal direction, or to both sides.

[0043] For example, the electrode lead 200 may include a first lead 220 and a second lead 240. The first lead 220 may be drawn out from one side of the cell case 300, and the second lead 240 may be drawn out from the other side of the cell case 300.

[0044] The first lead 220 is connected to the first electrode plate and may indicate either the positive or negative electrode. The second lead 240 is connected to the second electrode plate and may indicate either the positive or negative electrode.

[0045] The cell case 300 can house the electrode assembly 100 inside. That is, the cell case 300 may include a housing space for housing the electrode assembly 100 inside. In this case, the cell case 300 may house an electrolyte inside, and the electrode assembly 100 may be housed inside in a form in which the electrode assembly 100 is impregnated with the electrolyte. For example, the cell case 300 may include, but is not limited to, a metallic material (e.g., aluminum (Al)).

[0046] Furthermore, the cell case 300 may be configured to support the electrode lead 200. In this case, the electrode lead 200 may protrude a predetermined length outside the cell case 300. Although not shown, a lead film F may be interposed between the electrode lead 200 and the cell case 300 to seal the space between them.

[0047] The vent guide unit 400 is provided in the cell case 300 and may be configured to guide the discharge of vent gas to a certain area of ​​the cell case 300 as the internal pressure of the cell case 300 increases.

[0048] In a battery cell 10 as described in the present invention, thermal events such as thermal runaway may occur. In this case, high-temperature and high-pressure vent gas may be generated inside the cell case 300. If such vent gas is discharged randomly from the cell case 300, oxygen may flow into the cell case 300 from the part of the cell case 300 where the internal pressure has decreased due to the discharge of vent gas, which may increase the likelihood of ignition inside the battery cell 10.

[0049] To solve these problems, the vent guide unit 400 of the present invention is provided in the cell case 300 as described above, and is capable of guiding the vent gas to be discharged to a predetermined area of ​​the cell case 300. That is, if a thermal runaway phenomenon occurs inside the cell case 300, the vent guide unit 400 can guide the flow of vent gas to concentrate in the part of the cell case 300 other than the part to which the vent guide unit 400 is connected.

[0050] This allows the vent guide unit 400 to guide the discharge of vent gas by causing damage to a specific area of ​​the cell case 300. In this way, when high-pressure vent gas is discharged to a specific area of ​​the cell case 300, the inflow of oxygen into the interior of the cell case 300 from the area where the vent gas is discharged can be minimized.

[0051] According to this embodiment of the present invention, by guiding the discharge of vent gas to a specific area, the inflow of oxygen into the cell case 300 can be minimized. This reduces the possibility of ignition inside the battery cell 10, thereby strengthening the structural stability of the battery cell 10.

[0052] In particular, the vent guide section 400 may include a material that hardens due to heat conduction caused by an increase in the internal temperature of the cell case 300. For example, the vent guide section 400 may include, but is not limited to, clay that hardens when heated over a specific period of time.

[0053] On the other hand, the portion of the cell case 300 equipped with the vent guide section 400 may be a vulnerable part that is more susceptible to damage from the high-pressure vent gas discharged from inside the cell case 300 compared to the remaining portion. Such vulnerable parts will be explained in more detail in the related explanations described later.

[0054] In this case, the vent guide section 400 includes a material that hardens through heat conduction, thereby stably binding the aforementioned weak parts. As a result, the vent guide section 400 can prevent vent gas from being discharged from the weak parts to the outside of the cell case 300.

[0055] The vent guide section 400 mentioned above will be explained in more detail below.

[0056] Figure 4 is a diagram illustrating the venting process when thermal runaway occurs in battery cell 10 shown in Figure 1. In Figure 4, the vent gas is indicated by the reference numeral "G".

[0057] Referring to Figures 1 to 4, the vent guide portion 400 may be provided, for example, on one side of the cell case 300. The vent guide portion 400 may be coupled to a portion of the surface of the cell case 300.

[0058] In this case, in order to reproduce the thermal runaway environment of the battery cell 10, the temperature of the battery cell 10 was increased from 25°C to 150°C at a rate of 5°C / min, and then heated at approximately 150°C for 1 hour.

[0059] In this case, as the internal pressure of the cell case 300 increases due to the heating of the battery cell 10, the vent passage V through which the vent gas is discharged can be formed in a portion of the cell case 300 other than the portion to which the vent guide portion 400 is connected. The vent passage V can be formed adjacent to the vent guide portion 400. For example, the vent passage V can be formed in a corner region of the cell case 300.

[0060] In other words, the vent guide section 400 can guide the flow of vent gas to concentrate in the parts of the cell case 300 other than the weak parts to which the vent guide section 400 is attached, by stably binding the aforementioned weak parts. As a result, the vent guide section 400 can guide the discharge of vent gas in the parts of the cell case 300 other than the weak parts to which the vent guide section 400 is attached, by causing damage to the parts of the cell case 300 other than the weak parts to which the vent guide section 400 is attached.

[0061] Referring further to Figures 1 to 4, the cell case 300 may include a housing portion 320 configured to house the electrode assembly 100 inside, and a sealing portion 340 having a shape that extends outward for a certain length from the peripheral edge of the housing portion 320. The sealing portion 340 may include case terraces T on one side and the other side, respectively. On the other hand, the cell case 300 may include a first case member 300a and a second case member 300b. The peripheral regions of the first case member 300a and the second case member 300b may abut each other and be joined by heat welding to form the aforementioned sealing portion 340. Inside the sealing portion 340, a space is formed due to the separation between the first case member 300a and the second case member 300b, and such a space may become the housing portion 320 described above.

[0062] The case terrace T may refer to the region within the entire area of ​​the sealing portion 340 where the aforementioned electrode lead 200 is drawn out to the outside of the cell case 300.

[0063] That is, the case terrace T may be configured to extend a certain length from the housing portion 320 and support the electrode lead 200. In this case, the lead film F described above can seal the space between the electrode lead 200 and the cell case 300. Specifically, the lead film F may be interposed between the electrode lead 200 and the case terrace T.

[0064] On the other hand, the vent guide portion 400 may be provided on the case terrace T. In this case, the portion of the case terrace T that supports the electrode lead 200 may become the aforementioned weak point. That is, since the electrode lead 200 is interposed between one surface (e.g., the front) and the other surface (e.g., the rear) of the case terrace T, the portion of the case terrace T that supports the electrode lead 200 may be structurally weaker than other parts of the cell case 300. To reinforce the structural weakness of such a weak point, the vent guide portion 400 may be provided in the region of the case terrace T that includes the portion where the electrode lead 200 is located.

[0065] In this way, since the vent guide section 400 is provided on the case terrace T that supports the electrode lead 200, it is possible to prevent vent gas from being discharged from the part of the cell case 300 where the electrode lead 200 is located, and to guide the discharge of vent gas in the area of ​​the cell case 300 excluding the part where the electrode lead 200 is located.

[0066] In particular, the vent guide portion 400 can be coupled to the portion of the case terrace T where the electrode lead 200 is located. For example, the vent guide portion 400 can be coupled to at least a portion of the portion of the case terrace T where the first lead 220 is located or where the second lead 240 is located.

[0067] In other words, if the vent guide section 400 is connected only to the portion of the case terrace T where the electrode lead 200 is located, the vent guide section 400 can be configured to a minimum extent.

[0068] The vent guide section 400 may be configured to be coupled to one surface of the case terrace T and the other surface of the case terrace T in the cell case 300.

[0069] This makes it possible to more stably bind the first case member 300a and the second case member 300b in the case terrace T region supporting the electrode lead 200 so as not to damage the seal, and more reliably prevent vent gas from being discharged from the region in the cell case 300 where the electrode lead 200 is located or from an adjacent region.

[0070] Furthermore, as shown in Figures 1 to 3, the vent guide section 400 can be configured to surround not only a part of the cell case 300, but also a part of the lead film F interposed between the electrode lead 200 and the case terrace T. With this configuration of the present invention, it is possible to reliably prevent the phenomenon in which the sealing force decreases in the region where the electrode lead 200 is pulled out due to rising temperature and / or increased internal pressure.

[0071] On the other hand, although not shown in the figures, the vent guide portion 400 may be configured to surround not only a part of the cell case 300 but also a part of the electrode lead 200. With such a configuration of the present invention, it is possible to more reliably prevent the phenomenon in which the sealing force in the region where the electrode lead 200 is drawn out decreases due to the rise in temperature and / or the increase in internal pressure.

[0072] The vent guide portion 400 can guide the vent flow path V, through which vent gas is discharged, to form in a portion of the case terrace T other than the portion to which the vent guide portion 400 is connected, as the internal pressure of the cell case 300 increases. The vent guide portion 400 may include an opening through which the first lead 220 extends.

[0073] In other words, since the aforementioned vent guide section 400 can be coupled to a portion of the case terrace T, the vent guide section 400 can guide the flow of vent gas to concentrate in the portion of the case terrace T other than the portion to which the vent guide section 400 is coupled. As a result, the vent flow path V can be formed in the portion of the case terrace T other than the portion to which the vent guide section 400 is coupled.

[0074] According to this embodiment of the present invention, a vent channel V can be formed in the case terrace T provided on the periphery of the cell case 300. Therefore, compared to the case where the vent channel V is formed in other parts of the cell case 300, damage to the cell case 300 is minimized and the vent gas can be discharged to the outside of the cell case 300 more stably.

[0075] On the other hand, the vent guide section 400 may be configured to guide the vent flow path V to form in the corner portion of the case terrace T as the internal pressure of the cell case 300 increases.

[0076] Specifically, the vent channel V may be formed in the corner portion C located below the electrode lead 200 on the case terrace T as the internal pressure of the cell case 300 increases. Although not shown in detail, the vent channel V may also be formed in the corner portion located above the electrode lead 200 on the case terrace T. In this case, the vent guide portion 400 can be provided in the region of the case terrace T excluding the corner portion C located below the electrode lead 200 on the case terrace T, or in the region of the case terrace T excluding the corner portion located above the electrode lead 200 on the case terrace T.

[0077] This allows the vent guide unit 400 to guide the discharge of vent gas to the corner portion of the case terrace T, which is a part of the case terrace T, thereby further minimizing the inflow of oxygen into the cell case 300.

[0078] Preferably, the vent channel V can be formed in a corner portion C located below the electrode lead 200 on the case terrace T as the internal pressure of the cell case 300 increases. That is, when the vent channel V is formed in a corner portion C located below the electrode lead 200 on the case terrace T, the discharge of vent gas is guided downwards from the cell case 300, thereby minimizing the inflow of vent gas into the cell case 300.

[0079] In particular, the case terrace T may be configured such that at least a portion of the corner portion C at the corner is chamfered.

[0080] In this case, the corner portion of the case terrace T, which is configured to have a chamfered shape, may experience stress concentration compared to other parts. That is, the flow of vent gas may be more concentrated in the corner portion C of the case terrace T, which is configured to have a chamfered shape, than in other parts of the case terrace T. When the corner portion C of the case terrace T has a chamfered shape, the sealing width in the chamfered area may be narrower than in the remaining area. Therefore, in the corner portion C of the case terrace T, which is configured to have a chamfered shape, the formation of the vent flow path V may be easier when the internal pressure of the cell case 300 increases.

[0081] According to this embodiment of the present invention, when the battery cell 10 experiences thermal runaway, a vent channel V can be more easily formed in the case terrace T.

[0082] In particular, the corner portion of the case terrace T may be configured such that the corner portion C located below the electrode lead 200 is chamfered. Alternatively, although not shown in detail, the corner portion of the case terrace T may be configured such that the corner portion C located above the electrode lead 200 is chamfered.

[0083] In this case, since the vent gas is discharged downwards from the cell case 300, the upward flow of vent gas is suppressed, making it possible to guide the direction of vent gas discharge in a more consistent direction.

[0084] Figure 5 illustrates the venting process when thermal runaway occurs in a conventional battery cell, and Figure 6 illustrates the voltage and temperature changes over time in Figure 5. In Figure 5, the vent gas is represented by the reference symbol "G".

[0085] Referring to Figure 5, a conventional battery cell 10' includes an electrode assembly (not shown), electrode leads 200', and a cell case 300'.

[0086] In this process, to recreate the thermal runaway environment of a conventional battery cell 10', for example, the temperature of the battery cell 10' was increased from 25°C to 150°C at a rate of 5°C / min, and then heated at 150°C for 1 hour.

[0087] In this case, the vent passage V through which the vent gas is discharged is generated in the cell case 300' where the electrode lead 200' is supported. That is, in the case of a conventional battery cell 10', the vent gas is discharged towards the electrode lead 200' side.

[0088] In this case, as shown in Figure 6, it can be confirmed that a large temperature difference and voltage difference occur between the positive and negative electrode leads of the electrode lead 200'. From this, it can be confirmed that when a thermal runaway phenomenon occurs in the battery cell 10', there is a high possibility that vent gas will be discharged from the region in the cell case 300' where the negative electrode lead is drawn out.

[0089] On the other hand, in the case of the battery cell 10 of the present invention, the vent guide portion 400 can suppress the discharge of vent gas toward the electrode lead 200. For example, when the first lead 220 is configured as the negative electrode lead, the vent guide portion 400 can suppress the discharge of vent gas toward the first lead 220. Therefore, it is desirable that the vent guide portion 400 be coupled to the portion of the case terrace T where the negative electrode lead is located.

[0090] Figure 7 shows a battery cell 12 according to another embodiment of the present invention.

[0091] Since the battery cell 12 in this embodiment is similar to the battery cell 10 in the previously described embodiment, redundant explanations of configurations that are substantially the same or similar to those in the previously described embodiment will be omitted, and the following explanation will focus on the differences from the previously described embodiment.

[0092] Referring to Figure 7, the battery cell 12 may include two vent guides 400 provided on case terraces T located on both sides in the longitudinal direction of the cell case 300.

[0093] Specifically, the electrode lead 200 includes a first lead 220 and a second lead 240, the first lead 220 and the second lead 240 may be provided on both sides of the longitudinal direction of the cell case 300, respectively.

[0094] In other words, the vent guide section 400 can be connected to both the portion of the case terrace T where the first lead 220 is located and the portion where the second lead 240 is located.

[0095] In this case, the vent guide section 400 can prevent vent gas from being discharged from the portions where the electrode leads 200 are located on both sides in the longitudinal direction of the cell case 300 when the battery cell 12 experiences thermal runaway, and can also guide the vent gas to be discharged from the case terraces T located on both sides in the longitudinal direction of the cell case 300, thereby enabling stable and rapid discharge of vent gas.

[0096] Figure 8 shows a battery cell 14 according to yet another embodiment of the present invention.

[0097] Since the battery cell 14 in this embodiment is similar to the battery cell in the previously described embodiment, redundant explanations of configurations that are substantially the same or similar to those in the previously described embodiment will be omitted, and the following explanation will focus on the differences from the previously described embodiment.

[0098] Referring to Figure 8, unlike the embodiment described above, the battery cell 14 may have electrode leads 200 provided only on one side in the longitudinal direction of the cell case 300.

[0099] Specifically, the electrode lead 200 includes a first lead 220 and a second lead 240, the first lead 220 and the second lead 240 may be provided only on one longitudinal side of the cell case 300. The first lead 220 and the second lead 240 may extend through a vent guide portion 400 coupled to one side of the battery cell 14.

[0100] In this case, the vent guide section 400 is provided on a case terrace T located on one longitudinal side of the cell case 300, preventing vent gas from being discharged from the portion where the first lead 220 and the second lead 240 are located on one longitudinal side of the cell case 300. Furthermore, by providing the vent guide section 400 on the case terrace T on one longitudinal side of the cell case 300, the discharge of vent gas toward the electrode lead 200 can be suppressed, and the manufacturing cost of the vent guide section 400 can be minimized.

[0101] Figure 9 shows a battery cell according to yet another embodiment of the present invention. Since the battery cell 16 according to this embodiment is similar to the battery cell 12 of the previously described embodiment, redundant explanations of substantially identical or similar configurations will be omitted, and the following explanation will focus on the differences from the previously described embodiment.

[0102] Referring to Figures 2, 3, and 9, the battery cell 16 may further include a third vent guide portion 400 connected to at least one location on either one side of the battery cell 16 in the width direction (parallel to the Z-axis), in addition to the first and second vent guide portions 400 connected to one and the other side of the battery cell 12 in the longitudinal direction (parallel to the X-axis), respectively, according to the embodiment described above. The first vent guide portion 400 may be connected to a case terrace T provided on one side of the battery cells 12 and 16 in the longitudinal direction. The second vent guide portion 400 may be connected to a case terrace T provided on the other side of the battery cells 12 and 16 in the longitudinal direction. The third vent guide portion 400 may be connected to a sealing portion 340 connecting a pair of terrace portions T. Referring to Figures 2, 3, and 9, the cell case 300 may have a folded form in which the first case member 300a and the second case member 300b are integrally connected at one location on either one or the other side in the width direction. In this case, the third vent guide section 400 may be provided at a location on either one or the other side in the width direction of the battery cell 16 where the first case member 300a and the second case member 300b are not integrally connected.

[0103] With this configuration, in the sealing portion 340 where the first case member 300a and the second case member 300b are joined in contact, the vent guide portion 400 is connected to the area excluding the weak portion (for example, the chamfered corner portion C), thereby allowing control to guide the discharge of vent gas from the weak portion. Furthermore, by enabling such control of the venting position, venting can be made to occur in an area away from the electrode leads 220 and 240, thereby improving safety.

[0104] As described above, according to the embodiments of the present invention, the possibility of ignition inside the battery cells 10, 12, 14, and 16 is reduced, thereby enhancing the structural stability of the battery cells 10, 12, 14, and 16.

[0105] Furthermore, since the vent guide unit 400 can guide the discharge of vent gas from parts of the cell case 300 other than the weak point to which it is connected, it is possible to discharge vent gas in the intended direction.

[0106] Figure 10 shows a battery module M including the battery cell 10 of the present invention.

[0107] Referring to Figure 10, at least one battery cell 10 according to the present invention may constitute a battery module M. The battery module M according to the present invention may include at least one battery cell 10 according to the present invention. More specifically, at least one battery cell 10 constitutes a cell assembly 1, and the cell assembly 1 may be housed in a module case 5.

[0108] Such a module case 5 can be configured with a vent hole O at its lower part, and this vent hole O may be located adjacent to a corner portion C located below the electrode lead 200 on the case terrace T. This allows the vent gas discharged through the aforementioned vent path V to be easily discharged to the outside of the module case 5 through the vent hole O in the event of a thermal event such as thermal runaway in the battery cell 10. Furthermore, since the vent gas is discharged downwards from the module case 5, it is possible to prevent the vent gas from being discharged towards the driver in the automobile A (see Figure 12), which will be described later.

[0109] Figure 11 shows a battery pack P including the battery module M shown in Figure 10.

[0110] Referring to Figure 11, the battery module M according to the present invention can constitute a battery pack P by comprising at least one of these modules. The battery pack P according to the present invention may include at least one of these battery modules M. The battery pack P may further include a pack case for housing the battery modules M and various devices for controlling the charging and discharging of the battery pack P, such as a BMS (battery management system), a current sensor, and a fuse.

[0111] Figure 12 shows a car A including the battery pack P shown in Figure 11.

[0112] Referring to Figure 12, the battery pack P according to the present invention is applicable to an automobile A, such as an electric vehicle. An automobile A according to the present invention may include at least one of the battery packs P according to the present invention.

[0113] Although the present invention has been described above with reference to limited embodiments and drawings, it goes without saying that the present invention is not limited thereto, and that various modifications and variations are possible within the equivalent scope of the technical concept and claims of the present invention by persons with ordinary skill in the art to which the present invention pertains.

[0114] In this specification, terms indicating direction such as up, down, left, right, front, and back are used, but these terms are for the sake of convenience of explanation only, and it is obvious to those skilled in the art that the direction can change depending on the position of the object in question, the position of the observer, etc. [Explanation of symbols]

[0115] 1 Cell Assembly 5 Module Cases 10, 12, 14, 16 battery cells 100 electrode assembly 200 electrode leads 300 Cell Case 320 Storage Unit 340 Sealing section 400 Vent guide section A car P Battery Pack M Battery Module T Case Terrace V vent channel

Claims

1. Electrode assembly and A cell case configured to house the electrode assembly inside, The cell case includes a vent guide unit provided in the cell case, configured to guide the discharge of vent gas to a certain area of ​​the cell case as the internal pressure of the cell case increases, The aforementioned cell case is A housing section for housing the electrode assembly inside, It includes a sealing portion having a shape that extends a certain length from the housing portion, The vent guide section is provided in the case terrace, which is the region within the entire area of ​​the sealing section from which the electrode leads connected to the electrode assembly are drawn out. The vent guide portion is coupled to the portion of the case terrace where the electrode leads are located, and as the internal pressure of the cell case increases, it guides the vent passage through which the vent gas is discharged to be formed at the corner portion of the case terrace. The battery cell is characterized in that the case terrace has a form in which at least a portion of the corner portion is chamfered.

2. The battery cell according to claim 1, characterized in that the vent guide portion includes a material that hardens due to heat conduction caused by an increase in the internal temperature of the cell case.

3. The aforementioned vent guide section is, Bonded to a portion of the surface of the cell case, The battery cell according to claim 1, characterized in that, as the internal pressure of the cell case increases, the vent passage through which the vent gas is discharged is guided to form in a portion of the cell case other than the portion to which the vent guide portion is connected.

4. The aforementioned vent guide section is, The battery cell according to claim 1, characterized in that the cell case is configured to be coupled across one side of the case terrace and the other side of the case terrace.

5. The aforementioned vent guide section is, The battery cell according to claim 4, characterized in that it is configured to surround a portion of the lead film interposed between the electrode lead and the case terrace.

6. The aforementioned vent guide section is, The battery cell according to claim 4, characterized in that it is configured to surround a part of the electrode lead.

7. The aforementioned vent guide section is, The battery cell according to claim 1, characterized in that, as the internal pressure of the cell case increases, the vent passage through which the vent gas is discharged is guided to form in a portion of the case terrace other than the portion to which the vent guide portion is connected.

8. The aforementioned case terrace is The battery cell according to claim 1, characterized in that the corner portion located at the lower part of the electrode lead is chamfered.

9. The aforementioned vent guide section is, A first vent guide portion is coupled to a case terrace located on one side in the longitudinal direction of the battery cell, The battery cell according to claim 1, further comprising a second vent guide portion coupled to a case terrace located on the other side in the longitudinal direction of the battery cell.

10. The aforementioned vent guide section is, The battery cell according to claim 9, further comprising a third vent guide portion connected to a portion of the sealing portion that connects a case terrace located on one side in the longitudinal direction of the battery cell and a case terrace located on the other side in the longitudinal direction of the battery cell.

11. A battery module characterized by comprising at least one battery cell as described in any one of claims 1 to 10.

12. A battery pack characterized by comprising at least one of the battery modules described in claim 11.

13. An automobile characterized by comprising at least one battery pack as described in claim 12.

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