Secondary battery and battery box comprising same

Abstract

The present invention relates to a secondary battery and a battery box comprising same. According to one aspect of the present invention, the secondary battery comprises: an electrode assembly extending in one direction; and a pouch-type case for accommodating the electrode assembly, wherein the case comprises: a cup part and a cover part covering one side and the other side, respectively, of the electrode assembly; a first terrace part extending from the circumference of the cup part; a second terrace part extending from the cover part so as to overlap the first terrace part; a first-type coupling part extending in a circumferential direction of the cup part, and coupling the first and second terrace parts; and a non-coupling part extending in parallel with the first-type coupling part in the circumferential direction, wherein a length (L1) of the non-coupling part can be defined by [Equation 1]. Here, [Equation 1] satisfies C + 170 ≤ L1, and in [Equation 1], L1 is the length of the non-coupling part and C can be the electric capacity of the secondary battery.

Description

Secondary battery and battery box including the same

[0001] Cross-citation with related applications

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2024-0157197 filed on November 7, 2024, and all contents disclosed in the document of said Korean Patent Application are incorporated herein as part of this specification.

[0003] Technology field

[0004] The present invention relates to a secondary battery and a battery box including the same, and more specifically, to a secondary battery capable of charging and discharging electrical energy and a battery box including the same.

[0005] Although secondary batteries have been applied in small-scale fields such as mobile devices and laptop computers, research directions have recently expanded to medium and large-scale fields, and they are widely used in areas requiring high voltage and large capacity, such as Energy Storage Systems (ESS) and Electric Vehicles (EV). Secondary batteries can be provided in the form of battery cells consisting of an electrode assembly made of electrodes and a separator and a case that houses them. Depending on the case shape, such secondary batteries can be classified into pouch-type, prismatic, or cylindrical secondary batteries.

[0006] Meanwhile, as secondary batteries are utilized in various devices, the demand for their stability is increasing. To enhance the stability of secondary batteries, it is necessary to control the direction in which internal gases or flames are discharged under abnormal conditions where the battery's temperature or pressure rises. However, conventional pouch-type secondary batteries have a problem in that it is difficult to control the discharge direction of gases or flames because an electrode assembly is housed between a pair of opposing cup sections and a sealing section is provided along the perimeter to seal it. This is because rupture can occur along the entire perimeter of the cup sections, potentially causing the discharge of gases or flames.

[0007] The present invention has been devised to solve the above problems, and the objective of the present invention is to provide a secondary battery in which the direction of gas or flame discharge can be controlled, and a battery box including the same.

[0008] The problems of the present invention are not limited to those mentioned above, and other unmentioned problems will be clearly understood by a person skilled in the art to which the present invention pertains from the description below.

[0009] According to one aspect of the present invention, a secondary battery is provided comprising: an electrode assembly extending in one direction; and a pouch-type case for receiving the electrode assembly, wherein the case comprises: a cup portion and a cover portion covering one side and the other side of the electrode assembly, respectively; a first terrace portion extending from the circumference of the cup portion; a second terrace portion extending from the cover portion and overlapping with the first terrace portion; a first type coupling portion extending in the circumferential direction of the cup portion and coupling the first and second terrace portions; and a non-coupling portion extending parallel to the first type coupling portion in the circumferential direction, wherein the length (L1) of the non-coupling portion is defined by the following [Formula 1].

[0010] [Formula 1]

[0011] C + 170 ≤ L1

[0012] L1: Length of the above non-coupling part [mm]

[0013] C: Electric capacity of the above secondary battery [Ah]

[0014] At this time, the length (L1) of the non-coupling portion may be a length measured along the circumferential direction.

[0015] At this time, the cup portion has a predetermined length in the one direction and a predetermined width in a direction perpendicular to the one direction, the cup portion has a shape in which the length is longer than the width, and the length (L1) of the non-coupling portion can be extended parallel to the one direction.

[0016] At this time, the length (L1) of the above-mentioned non-coupling part can be defined by the following [Equation 2].

[0017] [Equation 2]

[0018] L1 ≤ L2 - 40

[0019] L2: Length of the above case [mm]

[0020] At this time, the cup portion has a predetermined length in the one direction and a predetermined width in the direction perpendicular to the one direction, and the length (L2) of the case may be a length measured along the one direction.

[0021] At this time, the above non-coupling portions are composed of a plurality of units, and the plurality of non-coupling portions can be arranged along the circumferential direction.

[0022] At this time, the distance between adjacent non-coupling parts among the plurality of non-coupling parts may be 60 mm or more.

[0023] At this time, the cup portion has a predetermined length in the one direction and a predetermined width in a direction perpendicular to the one direction, the cup portion has a shape in which the length is longer than the width, and the plurality of non-coupling portions can be arranged along the one direction.

[0024] At this time, the first type of joint may be made of a metal material.

[0025] At this time, the first type joint can be formed by a welding process.

[0026] At this time, the case may include a second type coupling part that extends parallel to at least one of the first type coupling part and the non-coupling part and combines the first and second terrace parts.

[0027] At this time, the second type coupling part can surround the cup part in the circumferential direction.

[0028] At this time, the second type coupling part may be located inside the first type coupling part.

[0029] At this time, the second type of joint may be made of a different material from the first type of joint.

[0030] At this time, the second type of joint may be made of a resin material.

[0031] At this time, the second type joint can be formed by a sealing process using heat or pressure.

[0032] At this time, the breaking force of the second type of joint may be smaller than the breaking force of the first type of joint.

[0033] At this time, the electrode assembly further includes an electrode lead for conducting electricity with the outside, and the case is provided with a window, and the electrode lead can be exposed to the outside of the case through the window.

[0034] At this time, the cover portion may have a cup shape facing the cup portion.

[0035] According to another aspect of the present invention, a battery box is provided comprising: a packaging; and a secondary battery accommodated in the packaging, wherein the secondary battery comprises: an electrode assembly extending in one direction; and a pouch-type case for accommodating the electrode assembly, wherein the case comprises: a cup portion and a cover portion covering one side and the other side of the electrode assembly, respectively; a first terrace portion extending from the periphery of the cup portion; a second terrace portion extending from the cover portion and overlapping with the first terrace portion; a first type coupling portion extending in the periphery direction of the cup portion and coupling the first and second terrace portions; and a non-coupling portion extending parallel to the first type coupling portion in the periphery direction, wherein the length (L1) of the non-coupling portion is defined by the following [Formula 1].

[0036] [Formula 1]

[0037] C + 170 ≤ L1

[0038] L1: Length of the above non-coupling part [mm]

[0039] C: Electric capacity of the above secondary battery [Ah]

[0040] According to one aspect of the present invention, a first type coupling part and a non-coupling part are provided to combine the first and second terrace parts along the perimeter of the first and second cup parts, and since the length of the non-coupling part is defined according to [Equation 1] below, gas or flame inside the case can be discharged through the non-coupling part. Through this, the direction of discharge of gas or flame can be controlled in abnormal situations, thereby improving the stability of the secondary battery. Here, [Equation 1] is C + 170 ≤ L1, where L1 is the length [mm] of the non-coupling part, and C is the electrical capacity [Ah] of the secondary battery.

[0041] The effects of the present invention are not limited to the effects described above, and unmentioned effects will be clearly understood by those skilled in the art from this specification and the attached drawings.

[0042] FIG. 1 is a perspective view of a secondary battery according to one embodiment of the present invention, viewed from above.

[0043] FIG. 2 is a plan view of a secondary battery according to one embodiment of the present invention. In this case, the portion equipped with the first and second type coupling portions is indicated as a hatched area.

[0044] Figure 3 is a cross-sectional view according to II of Figure 2.

[0045] Figure 4 is an enlarged view of part A of Figure 3.

[0046] FIG. 5 is a cross-sectional view along II-II of FIG. 2.

[0047] Figure 6 is an enlarged view of part B of Figure 5.

[0048] FIG. 7 is a plan view of a secondary battery according to another embodiment of the present invention. In this case, the portion equipped with the first and second type coupling portions is indicated as a hatched area.

[0049] Hereinafter, preferred embodiments of the present invention are described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. However, the present invention may be embodied in various different forms and is not limited or restricted by the following embodiments.

[0050] In order to clearly explain the present invention, detailed descriptions of related prior art that are irrelevant to the explanation or that may unnecessarily obscure the essence of the invention have been omitted. Furthermore, when assigning reference numerals to the components of each drawing in this specification, identical or similar reference numerals are assigned to identical or similar components throughout the entire specification.

[0051] In addition, terms or words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0052] FIG. 1 is a perspective view of a secondary battery according to an embodiment of the present invention viewed from above. FIG. 2 is a plan view of a secondary battery according to an embodiment of the present invention. In this case, the portion equipped with the first and second type coupling portions is indicated as a hatched area. FIG. 3 is a cross-sectional view according to II of FIG. 2. FIG. 4 is an enlarged view of portion A of FIG. 3. FIG. 5 is a cross-sectional view according to II-II of FIG. 2. FIG. 6 is an enlarged view of portion B of FIG. 5.

[0053] FIGS. 1 to 6 disclose a secondary battery according to an embodiment of the present invention. Referring to FIGS. 1 to 3, a secondary battery (1) according to an embodiment of the present invention may be a secondary battery for charging and discharging electrical energy. To this end, a secondary battery (1) according to an embodiment of the present invention may include an electrode assembly (10).

[0054] In this embodiment, the electrode assembly (10) may be an assembly composed of an electrode and a separator. The electrode may consist of a foil-shaped current collector made of copper (Cu) or aluminum (Al) and an electrode active material layer provided on one or both sides of the current collector. The separator may be made of an insulating material. A solid-state material may be used in place of the separator. The materials of the current collector, the electrode active material layer, and the separator are not particularly limited.

[0055] At this time, the electrodes and separators may be composed of multiple units. Some of the multiple electrodes may be positive electrodes, and the remaining parts may be negative electrodes. The multiple electrodes and separators may be stacked in one direction. The separators may be interposed between adjacent electrodes.

[0056] Such an electrode assembly (10) can be classified into a stacked type, a stacked and folding type, or a cylindrical type depending on the stacked structure or overall shape. In this embodiment, the type or shape of the electrode assembly (10) is not particularly limited as long as it can charge and discharge electrical energy.

[0057] Referring again to FIGS. 1 and FIGS. 2, a secondary battery (1) according to one embodiment of the present invention may include an electrode lead (20). The electrode lead (20) may be configured to conduct electricity to the outside of an electrode assembly (10).

[0058] To this end, the electrode lead (20) may be made of a conductive material. The electrode lead (20) may be provided in the form of a film or as a metal piece having a predetermined thickness. However, the structure or shape of the electrode lead (20) is not particularly limited.

[0059] At this time, there may be multiple electrode leads (20). Some of the multiple electrode leads (20) may be connected to the positive electrode of the electrode assembly (10), and the remaining parts may be connected to the negative electrode of the electrode assembly (10).

[0060] Referring to FIGS. 1 to 6, a secondary battery (1) according to one embodiment of the present invention may include a pouch-type case (30). The case (30) may be configured to accommodate an electrode assembly (10) and an electrolyte inside. The case (30) may perform the function of protecting the electrode assembly (10) and the electrolyte from external shock or contamination.

[0061] In this embodiment, the case (30) may be made of an exterior film. Here, the exterior film may have a certain flexibility so that it can be bent by an external force. The exterior film may have a multilayer structure.

[0062] For example, the exterior film may include a surface protection layer made of a polymer and provided on the outermost layer, a sealant layer made of a polymer and provided on the innermost layer, and a gas barrier layer made of metal interposed between the surface protection layer and the sealant layer.

[0063] Here, the polymer may include polyethylene terephthalate and / or polypropylene, and the metal may include iron (Fe), chromium (Cr), manganese (Mn), nickel (Ni) and / or aluminum. However, the layer structure of the exterior film and the materials forming it may be appropriately modified as needed.

[0064] In this embodiment, the case (30) may include a receiving portion (32). The receiving portion (32) may be configured to provide a receiving space (33) in which an electrode assembly (10) is placed. During the manufacturing process of the secondary battery (1), an electrolyte may be injected into the receiving space (33).

[0065] In this embodiment, the receiving portion (32) may include a cup portion (32a). The cup portion (32a) may be configured to cover the upper side (positive direction of the Z-axis) of the electrode assembly (10). The cup portion (32a) may have a cup shape that is concavely recessed upward (positive direction of the Z-axis). The upper part of the electrode assembly (10) may be received into this recessed portion.

[0066] In this embodiment, the cup portion (32a) may have a predetermined length in the front-rear direction (Y-axis direction) and a predetermined width in the left-right direction (X-axis direction) perpendicular to the length direction.

[0067] In this embodiment, the cup portion (32a) may have a shape in which the length is longer than the width. Hereinafter, the length direction and the width direction are respectively referred to as the length direction (Y-axis direction) and the width direction (X-axis direction) of the case (30).

[0068] Meanwhile, in this embodiment, the receiving portion (32) may include a cover portion (32b). The cover portion (32b) may be configured to cover the lower side (negative direction of the Z-axis) of the electrode assembly (10). As a result, the electrode assembly (10) can be entirely covered by the cup portion (32a) and the cover portion (32b). That is, the electrode assembly (10) can be sealed by the cup portion (32a) and the cover portion (32b).

[0069] In this embodiment, the cover portion (32b) may have a cup shape corresponding to the aforementioned cup portion (32a). As illustrated, the cover portion (32b) may have a shape that is concavely recessed downward (in the negative direction of the Z-axis). The lower part of the electrode assembly (10) may be inserted into this recessed portion.

[0070] Of course, the cover portion (32b) may have a different shape from the cup portion (32a) as needed. For example, the cover portion (32b) may have a flat film shape extending in the horizontal direction (X-axis and Y-axis direction). The shape of the cover portion (32b) is not particularly limited as long as it can seal the electrode assembly (10) together with the cup portion (32a).

[0071] Meanwhile, referring again to FIGS. 1 and 2, in this embodiment, a window (31) may be provided in the receiving portion (32) of the case (30). The window (31) may be configured to expose a portion of the receiving space (33) to the outside. The shape or position of the window (31) is not particularly limited.

[0072] In this embodiment, the electrode lead (20) may be exposed to the outside of the case (30) through the window (31). As a result, the electrode assembly (10) may be energized with an external power source or load through the electrode lead (20).

[0073] Referring again to FIGS. 1 to 6, the case (30) of a secondary battery (1) according to one embodiment of the present invention may include a terrace portion (34). The terrace portion (34) may be configured to seal the receiving portion (32) so that the receiving space (33) is isolated from the outside.

[0074] In this embodiment, the terrace portion (34) may include a first terrace portion (34a). The first terrace portion (34a) may extend from the periphery side of the cup portion (32a). The first terrace portion (34a) may be provided along the periphery direction of the cup portion (32a). The first terrace portion (34a) may have a ring shape surrounding the cup portion (32a). Here, the periphery direction of the cup portion (32a) may be a direction that wraps around the vertical direction (Z-axis direction).

[0075] In this embodiment, the terrace portion (34) may include a second terrace portion (34b). The second terrace portion (34b) may extend from the cover portion (32b). The second terrace portion (34b) may be provided along the circumferential direction of the cup portion (32a). The second terrace portion (34b) may also have a ring shape surrounding the cup portion (32a).

[0076] In this embodiment, the second terrace portion (34b) may overlap with the first terrace portion (34a) in the direction in which the cup portion (32a) and the cover portion (32b) are arranged (i.e., the vertical direction (Z-axis direction)). By combining the second terrace portion (34b) and the first terrace portion (34a), the receiving portion (32) can be sealed, and the receiving space (33) can be isolated from the outside.

[0077] Referring to FIGS. 2 to 6, a case (30) of a secondary battery (1) according to one embodiment of the present invention may include a first type coupling part (36) and a non-coupling part (37). The first type coupling part (36) may be configured to combine the first and second terrace parts (34a, 34b) with each other.

[0078] In this embodiment, the first type joint (36) can be formed by a welding process. For example, the first type joint (36) can be formed by laser welding performed at 600 to 700 degrees. The first type joint (36) can be formed by solidifying the metal after it has been melted.

[0079] At this time, the metal may be part of the gas barrier layer of the exterior film. More specifically, a portion of the exterior film constituting the first and second terrace portions (34a, 34b) of the case (30) may have the gas barrier layer exposed for welding.

[0080] Of course, if necessary, a separate metal film may be interposed between the first and second terrace sections (34a, 34b), and the welding may be performed to form the first type joint section (36).

[0081] Meanwhile, in this embodiment, the first type coupling part (36) may extend along the circumferential direction of the cup part (32a). As a result, the circumferential side of the receiving part (32) may be sealed by the first type coupling part (36).

[0082] In addition, in this embodiment, the non-coupling portion (37) may extend parallel to the first type coupling portion (36) and the cup portion (32a) in the circumferential direction. Alternatively, the first type coupling portion (36) and the non-coupling portion (37) may be connected to each other in the circumferential direction to form a single ring shape surrounding the cup portion (32a). Alternatively, the first type coupling portion (36) may be provided in one section based on the circumferential direction, and the non-coupling portion (37) may be provided in the remaining section.

[0083] In this embodiment, the non-coupling portion (37) may be defined as a portion where the first and second terrace portions (34a, 34b) are not joined to each other by the first type coupling portion (36). In the non-coupling portion (37), the first and second terrace portions (34a, 34b) may be separated from each other. Alternatively, in the non-coupling portion (37), the first and second terrace portions (34a, 34b) may be in contact with each other but may be in a state where they can be easily separated by an external force.

[0084] Such a non-coupling part (37) can function as a passage for gas or flames in the receiving space (33) to be discharged when an abnormal situation occurs in the secondary battery (1). That is, the discharge of gas or flames is restricted to the part of the perimeter of the receiving part (32) equipped with the first type coupling part (36), and the discharge of gas or flames can be induced toward the non-coupling part (37). In this way, since the discharge direction of gas and flames in the secondary battery (1) can be controlled toward the non-coupling part (37), high stability can be achieved.

[0085] In this embodiment, the length (L1) of the non-coupling part (37) can be defined by the following [Equation 1]. In this case, the length (L1) of the non-coupling part (37) may be the length measured in the length direction (Y-axis direction) of the case (30).

[0086] [Formula 1]

[0087] C + 170 ≤ L1

[0088] L1: Length of the above non-coupling part [mm]

[0089] C: Electric capacity of the above secondary battery [Ah]

[0090] The inventors performed a thermal runaway (TP) experiment simulating an abnormal situation using a secondary battery according to a comparative example and an embodiment, which have the same electrical capacity of 80Ah but different lengths (L1) of the non-coupling portion (37). In Comparative Example 1, the length (L1) was 150mm, in Example 1, the length (L1) was 250mm, and in Example 2, the length (L1) was 300mm.

[0091] In the above experiment, the inventors confirmed that in Comparative Example 1, the area near the non-connecting part (37) was additionally fractured for a length of approximately 70 mm, and flames and gases were discharged to the additionally fractured area, whereas in Examples 1 and 2, no additional fracture occurred in the area near the non-connecting part (37), and the discharge of gases or flames was properly induced toward the non-connecting part (37).

[0092] Additionally, the inventors performed additional thermal runaway tests on Comparative Example 2, which has an electrical capacity of 160 Ah and a length (L1) of 250 mm. In the tests, the inventors confirmed that a portion near the non-coupling part (37) is additionally fractured for a length of approximately 80 mm, and that flames and gases are discharged through the additionally fractured portion.

[0093] This suggests that if the length (L1) of the non-coupling part (37) has a length defined according to [Equation 1] above, the direction of discharge of gas or flame can be very effectively controlled toward the non-coupling part (37).

[0094] Meanwhile, in this embodiment, the length (L1) of the non-coupling part (37) can be defined by the following [Equation 2]. In this case, the length (L2) of the case (30) in [Equation 2] may be the length measured in the length direction (Y-axis direction) of the cup part (32a).

[0095] [Equation 2]

[0096] L1 ≤ L2 - 40

[0097] L1: Length of the above non-coupling part [mm]

[0098] L2: Length of the above case [mm]

[0099] In this way, the non-coupling portion (37) having a length (L1) defined according to [Equation 2] can be used to secure a minimum strength for the frame supporting the secondary battery (1) when the secondary battery (1) is subsequently housed in a battery pack. In other words, the secondary battery (1) can be stably supported on the frame by the first type coupling portion (36) provided on both sides in the longitudinal direction (Y-axis direction) of the non-coupling portion (37).

[0100] Meanwhile, referring again to FIGS. 2 to 6, the case (30) of a secondary battery (1) according to one embodiment of the present invention may include a second type coupling part (38). The second type coupling part (38) may be configured to combine the first and second terrace parts (34a, 34b) together with the first type coupling part (36).

[0101] In this embodiment, the second type joint (38) can be formed by a sealing process using heat or pressure. The second type joint (38) can be made of a resin material that can be solidified after being melted by heat or pressure. The sealing process can be performed at a lower temperature than the welding process that forms the first type joint (36). For example, the temperature of the sealing process can be around 200 degrees.

[0102] This second type of joint (38) can be formed by solidifying the sealant layer of the outer film constituting the case (30) after it has been partially melted. However, the process by which the second type of joint (38) is formed or the material forming it is not particularly limited as long as the first and second terrace portions (34a, 34b) can be joined together.

[0103] In this embodiment, the second type connecting part (38) may extend in the circumferential direction of the cup part (32a). At this time, the second type connecting part (38) may wrap around the cup part (32a) in the circumferential direction. In other words, the second type connecting part (38) may have a ring shape that surrounds the cup part (32a).

[0104] As a result, the perimeter of the receiving portion (32) can be completely sealed by the second type connecting portion (38). Accordingly, the second type connecting portion (38) can effectively prevent the electrolyte from leaking out of the receiving portion (32).

[0105] In this embodiment, the second type coupling part (38) may be located inside the first type coupling part (36). Here, the fact that the second type coupling part (38) is located inside the first type coupling part (36) may mean that the distance between the second type coupling part (38) and the receiving part (32) is shorter than the distance between the first type coupling part (36) and the receiving part (32). In other words, the ring shape formed by the second type coupling part (38) may be located inside the ring shape formed by the first type coupling part (36) and the non-coupling part (37).

[0106] This configuration may be for effective insulation between the electrode assembly (10) and the case (30) in the receiving space (33). More specifically, it is preferable that the inner surface of the receiving portion (32) (or the inner wall of the receiving space (33)) be provided with a configuration for insulating the electrode assembly (10) and the case (30). This configuration may be a sealant layer of an outer film.

[0107] This sealant layer can be extended from the first and second terrace sections (34a, 34b) of the receiving section (32) to the area where the second type joint (38) is provided. This is because the second type joint (38) can be made of a sealant layer that has been melted and then solidified. As a result, insulation by the sealant layer can be effectively achieved even on the periphery side of the receiving section (32).

[0108] Contrary to the present embodiment, if the first type coupling part (36) is located inside the second type coupling part (38), the possibility of insulation breakdown on the periphery side of the receiving part (32) may be slightly higher. This is because the first type coupling part (36) may be made of metal formed by a welding process, and a part of this metal may be exposed to the receiving space (33).

[0109] Of course, if the distance between the first type coupling part (36) and the receiving part (32) is sufficient to maintain insulation, the first type coupling part (36) may be located inside the second type coupling part (38).

[0110] At this time, the breaking force of the second type joint (38) may be smaller than the breaking force of the first type joint (36). Here, the fact that the breaking force of the second type joint (38) is smaller than that of the first type joint (36) may mean that the second type joint (38) breaks at a lower pressure or temperature.

[0111] Generally, the second type joint (38) formed by the sealing process may have a smaller breaking force than the first type joint (36) formed by the welding process. This configuration may be intended to allow flames or gases to be guided toward the non-joint (37) side by maintaining the bonding force of the first type joint (36) even when the temperature or pressure rises to the point where the second type joint (38) breaks.

[0112] As previously explained, in a secondary battery (1) according to one embodiment of the present invention, a non-coupling portion (37) that can function as a passage for gas or flame is provided between the first and second terrace portions (34a, 34b), so that the direction of discharge of gas or flame can be effectively controlled in abnormal situations.

[0113] In particular, in this embodiment, the length (L1) of the non-coupling part (37) is defined by the aforementioned [Equation 1] and / or [Equation 2], so the direction of discharge of gas or flame can be controlled more accurately.

[0114] Hereinafter, a secondary battery according to another embodiment of the present invention will be described.

[0115] FIG. 7 is a plan view of a secondary battery according to another embodiment of the present invention. In this case, the portion equipped with the first and second type coupling portions is indicated as a hatched area. At this time, the differences from the secondary battery according to the first embodiment of the present invention described above will be described in detail.

[0116] FIG. 7 discloses a secondary battery according to another embodiment of the present invention. Referring to FIG. 7, the non-coupling portion (137) of the secondary battery (101) according to another embodiment of the present invention may be composed of a plurality of portions.

[0117] At this time, a plurality of non-coupling portions (137) may be arranged along the circumferential direction of the receiving portion (32) (i.e., the circumferential direction of the cup portion). And, a first type coupling portion (136) may be provided between adjacent non-coupling portions (137).

[0118] Here, a plurality of non-coupling portions (137) may be located in a portion extending along the longitudinal direction (Y-axis direction) of the cup portion in the terrace portion (34). In the said portion, a plurality of non-coupling portions (137) may be arranged along the longitudinal direction (Y-axis direction).

[0119] This is because the portion of the cup section extending in the width direction (X-axis direction) from the terrace section (34) is shorter than the portion extending in the length direction (Y-axis direction), so the bonding force by the first type of joint (136) is relatively weak. If a non-joining portion (137) is provided in such a short width direction portion, the area near the non-joining portion (137) may unexpectedly break and release gas or flames.

[0120] In this embodiment, the distance (d) between adjacent non-coupling parts (137) among a plurality of non-coupling parts (137) may be 60 mm or more. As a result, the first type coupling part (136) provided between adjacent non-coupling parts (137) can generate sufficient coupling force.

[0121] Therefore, additional breakage between adjacent non-connected parts (137) and the release of gas or flame in an unexpected direction can be prevented. At this time, the distance (d) may increase or decrease depending on the electrical capacity of the secondary battery (101). For example, the distance (d) may increase or decrease in proportion to the electrical capacity of the secondary battery (101).

[0122] Meanwhile, a battery box according to one embodiment of the present invention may include packaging and a secondary battery. In this case, the secondary battery may be a secondary battery (1, 101) according to the embodiment of the present invention described above (shown in FIG. 1 and FIG. 7). The secondary battery may be composed of a plurality of units.

[0123] In this embodiment, the secondary battery may be housed in a package. The package may be configured to protect the secondary battery from external shock or contamination. To this end, the package may have an enclosure shape with a predetermined space inside. However, the structure or shape of the package is not particularly limited as long as it can house and protect the secondary battery.

[0124] Although the present invention has been described above by limited embodiments and drawings, the present invention is not limited thereto, and various implementations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs.

[0125] [Explanation of the symbol]

[0126] 1, 101: Secondary battery 10: Electrode assembly

[0127] 20: Electrode lead 30, 130: Case

[0128] 31: Window 32: Reception area

[0129] 32a: Cup part 32b: Cover part

[0130] 33: Accommodation space 34: Terrace area

[0131] 34a: 1st terrace section 34b: 2nd terrace section

[0132] 36, 136: Type 1 joint 37: Non-joint

[0133] 38, 138: Type 2 joint

Claims

1. Electrode assembly extended in one direction; and It includes a pouch-type case for accommodating the above electrode assembly, and The above case is, A cup portion and a cover portion covering one side and the other side of the electrode assembly, respectively; A first terrace portion extending from the perimeter of the cup portion; A second terrace portion extending from the above cover portion and overlapping with the first terrace portion; A first type connecting part extending in the circumferential direction of the cup portion and connecting the first and second terrace portions; and It includes the first type coupling portion and the non-coupling portion extended parallel to the circumferential direction, The length (L1) of the above-mentioned non-coupling portion is a secondary battery defined by the following [Formula 1]. [Formula 1] C + 170 ≤ L1 L1: Length of the above non-coupling part [mm] C: Electric capacity of the above secondary battery [Ah] 2. In Paragraph 1, The length (L1) of the above-mentioned non-coupling portion is a length measured along the circumferential direction, in a secondary battery.

3. In Paragraph 2, The above cup portion has a predetermined length in the one direction and a predetermined width in the direction perpendicular to the one direction, The above-mentioned cup portion has a shape in which its length is longer than its width, The length (L1) of the above non-coupling portion is a secondary battery that extends parallel to the above one direction.

4. In Paragraph 1, The length (L1) of the above-mentioned non-coupling portion is a secondary battery defined by the following [Equation 2]. [Equation 2] L1 ≤ L2 - 40 L2: Length of the above case [mm] 5. In Paragraph 4, The above cup portion has a predetermined length in the one direction and a predetermined width in the direction perpendicular to the one direction, The length (L2) of the above case is a secondary battery, which is a length measured along the above one direction.

6. In Paragraph 1, The above non-coupling part is composed of a plurality of parts, and The above plurality of non-coupling parts are arranged along the circumferential direction, forming a secondary battery.

7. In Paragraph 6, A secondary battery in which the distance between adjacent non-coupled parts among the plurality of non-coupled parts is 60 mm or more.

8. In Paragraph 6, The above cup portion has a predetermined length in the one direction and a predetermined width in the direction perpendicular to the one direction, The above-mentioned cup portion has a shape in which its length is longer than its width, The above plurality of non-coupling parts are arranged along the above one direction, forming a secondary battery.

9. In Paragraph 1, The above-mentioned first type coupling part is a secondary battery made of a metal material.

10. In Paragraph 9, The above-mentioned first type joint is a secondary battery formed by a welding process.

11. In Paragraph 1, The above case is, A secondary battery comprising a second type coupling portion that extends parallel to at least one of the first type coupling portion and the non-coupling portion and combines the first and second terrace portions.

12. In Paragraph 11, The above second type coupling portion is a secondary battery that surrounds the cup portion in the circumferential direction.

13. In Paragraph 11, The above second type coupling part is a secondary battery located inside the above first type coupling part.

14. In Paragraph 11, The above second type coupling part is made of a different material from the above first type coupling part, in a secondary battery.

15. In Paragraph 11, The above-mentioned second type coupling part is a secondary battery made of a resin material.

16. In Paragraph 15, The above-mentioned second type joint is a secondary battery formed by a sealing process using heat or pressure.

17. In Paragraph 11, A secondary battery in which the breaking force of the second type of joint is smaller than the breaking force of the first type of joint.

18. In Paragraph 1, The above electrode assembly further includes an electrode lead for energizing the outside, and In the above case, a window is provided, and The above electrode lead is a secondary battery exposed to the outside of the case through the above window.

19. In Paragraph 1, The above cover portion is a secondary battery having a cup shape facing the above cup portion.

20. Packaging; and Includes a secondary battery housed in the above packaging, The above secondary battery is, Electrode assembly extended in one direction; and It includes a pouch-type case for accommodating the above electrode assembly, and The above case is, A cup portion and a cover portion covering one side and the other side of the electrode assembly, respectively; A first terrace portion extending from the perimeter of the cup portion; A second terrace portion extending from the above cover portion and overlapping with the first terrace portion; A first type connecting part extending in the circumferential direction of the cup portion and connecting the first and second terrace portions; and It includes the first type coupling portion and the non-coupling portion extended parallel to the circumferential direction, The length (L1) of the above-mentioned non-coupling portion is a battery box defined by the following [Formula 1]. [Formula 1] C + 170 ≤ L1 L1: Length of the above non-coupling part [mm] C: Electric capacity of the above secondary battery [Ah]

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