Soft package battery cell and battery module

Abstract

The utility model provides a soft package battery cell and a battery module, and the soft package battery cell comprises: a naked battery cell having a tab; the conducting strip is electrically connected with the tab; the soft coating film comprises two half films arranged on two opposite sides of the naked battery cell; the conducting strip extends out of the containing cavity, and sealant is arranged between the half film and the conducting strip. The two half films are in hot melting connection, and the half films and the sealant are in hot melting connection, so that an edge sealing area surrounding the naked battery cell is formed; the edge sealing area comprises a first sealing section, a second sealing section and a third sealing section which are sequentially connected end to end, and the included angle a between the second sealing section and the third sealing section is larger than or equal to 105 degrees and smaller than or equal to 150 degrees. According to the soft package battery cell and the battery module provided by the invention, the space which is defined by the top sealing sub-region in the edge sealing region and is used for storing produced gas can be relatively sufficient, and the size of the soft package battery cell can also meet the design requirement of high energy density of the whole battery pack.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a pouch cell and a battery module. Background Technology

[0002] In pursuit of greater driving range, current power battery systems tend to utilize ternary cathodes and silicon-based anodes with higher energy density. The application of high-energy-density systems has further propelled the development of high-end electric vehicles. While high-energy-density systems bring benefits in terms of driving range, they also introduce corresponding drawbacks, such as decreased cycle performance and safety, and increased gas production. For pouch batteries, during cyclic charging and discharging, interfacial reactions between the electrodes and electrolyte produce gas. This not only deteriorates the cell interface but may also cause the cell to swell, leading to the failure of the pouch film encapsulating the bare cell and resulting in leakage.

[0003] To prevent failure of the pouch cell's encapsulation, a space for storing generated gas needs to be provided at the end of the pouch cell; this space can be referred to as an air pocket. However, the applicant's research found that in related technologies, to improve the overall energy density of the battery pack, the module assembly space needs to be compressed as much as possible. In this case, the design margin left for the air pocket is small, limiting the air pocket's gas storage space. Utility Model Content

[0004] In view of this, the purpose of this application is to propose a pouch cell and battery module to at least partially solve the problem of how to maximize the gas storage space of the gas bag while meeting the design requirements of high energy density.

[0005] Based on the above objectives, a first aspect of this application provides a pouch cell, the pouch cell having two sides disposed opposite each other along a first direction, the pouch cell comprising: a bare cell having two tabs disposed opposite each other along a second direction; a conductive sheet electrically connected to the tabs; a pouch film comprising two half-films disposed on opposite sides of the bare cell along a third direction, the two half-films forming a receiving cavity, the bare cell being disposed within the receiving cavity; the conductive sheet extending out of the receiving cavity, and a sealant disposed between the half-film and the conductive sheet; the two half-films being thermally fused together and the half-films... A heat-fused connection is formed between the sealant and the surface to create a sealing area surrounding the bare battery cell. The sealing area includes a top sealing sub-area located on one side of the conductive sheet along a first direction. The top sealing sub-area includes a first sealing segment, a second sealing segment, and a third sealing segment connected end-to-end in sequence. The end of the first sealing segment away from the second sealing segment extends to the sealant, and the end of the third sealing segment away from the second sealing segment extends to the side surface. The first direction, the second direction, and the third direction are mutually perpendicular. The included angle between the second sealing segment and the third sealing segment is α, where 105°≤α≤150°.

[0006] Optionally, the bare cell includes a body, the tab is formed at the end of the body, the first sealing segment and the third sealing segment are both parallel to the edge of the end, the length of the top sealing sub-region along the first direction is L1, the distance along the second direction between the edge of the first sealing segment away from the bare cell and the edge of the third sealing segment near the bare cell is L2, 30mm≤L1≤40mm, and 12mm≤L2≤22mm.

[0007] Optionally, a first rounded corner is provided at the connection between the first sealing segment and the second sealing segment, and a second rounded corner is provided at the connection between the second sealing segment and the third sealing segment, wherein the radius of the second rounded corner is greater than the radius of the first rounded corner.

[0008] Optionally, the radius of the first fillet is 10 mm to 18 mm.

[0009] Optionally, the radius of the second fillet is 12mm to 20mm.

[0010] Optionally, the first rounded corner has a first starting end near the first sealing segment, the second rounded corner has a second ending end near the third sealing segment, the distance between the first starting end and the second ending end along the first direction is L4, the distance between the extension line of the second sealing segment to the third sealing segment and the second ending end along the first direction is L3, and L3 / L4≥0.3.

[0011] Optionally, the dimension of the first sealing segment along the second direction is defined as the width b of the top sealing sub-region, where 4mm ≤ b ≤ 12mm.

[0012] Optionally, the side surface includes a first side surface and a second side surface; along the first direction, the distance between the conductive sheet and the first side surface is greater than the distance between the conductive sheet and the second side surface, and the top sealing sub-region is at least disposed between the conductive sheet and the first side surface.

[0013] Optionally, the side surface includes a first side surface and a second side surface; along the first direction, the distance between the conductive sheet and the first side surface is equal to the distance between the conductive sheet and the second side surface, and the top sealing sub-area is provided on both sides of the conductive sheet along the first direction.

[0014] Based on the same inventive concept, the second aspect of this application also provides a battery module, including the pouch cell as described in the first aspect.

[0015] As can be seen from the above, the soft-pack battery cell and battery module provided in this application, by limiting 'a' to 105°≤a≤150°, can at least limit the structure of the second sealing segment, so that there is sufficient space between the second sealing segment and the electrode tab at least along the first direction. This allows for sufficient space for storing gas generated within the top sealing sub-region of the sealing edge area. Simultaneously, the overall size of the soft-pack battery cell defined by the sealing edge area can also meet the high energy density design requirements of the battery pack as a whole. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a partial schematic diagram of a pouch cell according to an embodiment of this application;

[0018] Figure 2 for Figure 1 Schematic diagram of the cross section AA;

[0019] Figure 3 This is a schematic diagram of a pouch cell with the first structure according to an embodiment of this application before cycling;

[0020] Figure 4 This is a schematic diagram of a soft-pack battery cell with the first structure of this application being cycled at 45°C to 550cls;

[0021] Figure 5 This is a schematic diagram of a pouch cell with the second structure according to an embodiment of this application before cycling;

[0022] Figure 6 This is a schematic diagram of a pouch cell with the second structure according to an embodiment of this application, which is cycled at 45°C to 550cls.

[0023] Explanation of reference numerals in the attached figures:

[0024] 100. Bare cell; 110. Terminal; 120. Tab; 130. Main body;

[0025] 200. Conductive sheet; 300. Sealant;

[0026] 400. Soft film; 410. Sealing area; 411. Top sealing area; 4111. First sealing section; 4112. Second sealing section; 4113. Third sealing section; 412. Side sealing area; 413. First rounded corner; 4131. First starting end; 4132. First ending end; 414. Second rounded corner; 4141. Second starting end; 4142. Second ending end; 420. Half film; 430. Receiving cavity; 431. Air bag space;

[0027] 500, Side view; 510, First side view; 520, Second side view. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0029] It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components described in these embodiments do not limit the scope of this application.

[0030] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0031] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0032] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0033] Figure 1 This shows a partial schematic diagram of a pouch cell. Figure 2 Showing Figure 1 A schematic diagram of the cross-section AA in the middle.

[0034] like Figure 1 and Figure 2This application provides a pouch cell, which has a first direction (e.g., Figure 1 The pouch cell includes two opposite sides 500 (in the X direction), comprising: a bare cell 100 having a shape along the second direction (e.g., ... Figure 1 and Figure 2 Two tabs 120 are arranged opposite each other in the Y direction; a conductive sheet 200 is electrically connected to the tabs 120; a soft film 400 includes a third direction (e.g., Figure 2 Two half-films 420 are respectively disposed on opposite sides of the bare battery cell 100 in the Z direction. The two half-films 420 together form a receiving cavity 430, and the bare battery cell 100 is disposed within the receiving cavity 430. A conductive sheet 200 extends out of the receiving cavity 430, and a sealant 300 is disposed between the half-films 420 and the conductive sheet 200. The two half-films 420 are heat-fused together, and the half-films 420 and the sealant 300 are heat-fused together to form a sealing area 410 surrounding the bare battery cell 100. The sealing area 410 includes a region located along the first direction on the conductive sheet 200. The top sealing area 411 on one side includes a first sealing segment 4111, a second sealing segment 4112, and a third sealing segment 4113 connected end to end in sequence. The end of the first sealing segment 4111 away from the second sealing segment 4112 extends to the sealant 300, and the end of the third sealing segment 4113 away from the second sealing segment 4112 extends to the side 500. The first direction, the second direction, and the third direction are perpendicular to each other. The included angle between the second sealing segment 4112 and the third sealing segment 4113 is α, where 105°≤α≤150°.

[0035] For example, 'a' can be 105°, 110°, 115°, 120°, 125°, 130°, 135°, 140°, 145° or 150°.

[0036] For example, the flexible film 400 can be an aluminum-plastic film.

[0037] For example, side 500 is a narrower surface between the two ends 110 of the pouch cell.

[0038] For example, the two tabs 120 include a positive tab and a negative tab, and the pouch cell may include two conductive sheets 200, one of which is electrically connected to the positive tab to form the positive electrode of the pouch cell, and the other conductive sheet 200 is electrically connected to the negative tab to form the negative electrode of the pouch cell.

[0039] For example, the conductive sheet 200 and the tab 120 are welded together to achieve an electrical connection between them.

[0040] For example, both half-films 420 cover the bare cell 100 along a third direction. In the sealing area 410, for the portion where the sealant 300 is provided, the sealing area 410 is formed by heat-melting the sealant 300 and the half-film 420; for the portion where the sealant 300 is not provided, the sealing area 410 is formed by heat-melting the two half-films 420 together.

[0041] The frame-shaped area formed by the sealing area 410 is the receiving cavity 430, such as Figure 1 The middle portion of the receiving cavity 430 is used to house the body 130 of the bare battery cell 100, while the space between the end 110 and the sealant 300 is used to store gas, referred to as the gas bag space 431. For the top sealing sub-area 411 near the end 110, the third sealing section 4113 is close to the end 110, and the first sealing section 4111 is the portion of the sealing edge area 410 away from the end 110 along the second direction.

[0042] Understandably, the tilt angle 'a' of the second sealing segment 4112 is positively correlated with the size of the air bag space 431. If 'a' is too small, the second sealing segment 4112 will be too close to the tab 120, resulting in an insufficient air bag space 431. This would lead to insufficient space inside the receiving cavity 430 for storing gas, increasing the risk of failure of the soft-pack film 400. However, if 'a' is too large, the overall size of the soft-pack cell in this embodiment will be too large. Consequently, the assembly space of the battery module formed by the soft-pack cell will be too large, resulting in a lower overall energy density of the battery pack.

[0043] To avoid the above problems, this embodiment limits a to 105°≤a≤150°, which can ensure that the battery pack has a high energy density while providing sufficient space for storing gas in the pouch cell.

[0044] The pouch cell provided in this embodiment, by limiting 'a' to 105°≤a≤150°, at least defines the structure of the second sealing segment 4112, ensuring sufficient space between the second sealing segment 4112 and the tab 120 at least along the first direction. This allows for sufficient space for gas storage defined by the top sealing sub-region 411 in the sealing edge region 410. Simultaneously, the overall size of the pouch cell defined by the sealing edge region 410 also meets the high energy density design requirements of the battery pack.

[0045] like Figure 1In some embodiments, the bare cell 100 includes a body 130, a tab 120 formed at the end 110 of the body 130, a first sealing section 4111 and a third sealing section 4113 both parallel to the edge of the end 110, the length of the top sealing sub-region 411 along a first direction is L1, and the distance along a second direction between the edge of the first sealing section 4111 away from the bare cell 100 and the edge of the third sealing section 4113 near the bare cell 100 is L2; ​​30mm≤L1≤40mm, and 12mm≤L2≤22mm.

[0046] For example, L1 can be 30mm, 31mm, 32mm, 33mm, 34mm, 35mm, 36mm, 37mm, 38mm, 39mm or 40mm.

[0047] For example, L2 can be 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, 21mm or 22mm.

[0048] For example, the body 130 includes a positive electrode sheet, a negative electrode sheet, and a separator separating the positive electrode sheet and the negative electrode sheet. The positive electrode sheet, the negative electrode sheet, and the separator can be formed into a wound structure or a stacked structure. A portion of the positive electrode sheet can extend out of one end 110 of the body 130 to form a positive electrode tab, and a portion of the negative electrode sheet can extend out of the other end 110 of the body 130 to form a negative electrode tab.

[0049] In summary, besides the tilt angle α of the second sealing segment 4112, the distance along the second direction between the third sealing segment 4113 and the first sealing segment 4111 is also strongly correlated with the size of the airbag space 431, and this distance along the second direction is positively correlated with L2. Furthermore, the size of the airbag space 431 is also positively correlated with the distance L1 between the first sealing segment 4111 and the side 500.

[0050] Understandably, if L1 and L2 are too large, the overall size of the pouch cell in this embodiment will be too large, resulting in an excessively large assembly space for the battery module formed by the pouch cell, which in turn will lead to a lower overall energy density of the battery pack. However, if L1 and L2 are too small, the air bag space 431 will be too small, resulting in insufficient space inside the receiving cavity 430 for storing generated gas, which may easily lead to the risk of failure of the pouch film 400 encapsulation.

[0051] To avoid the above problems, in this embodiment, L1 and L2 are respectively limited to 30mm≤L1≤40mm and 12mm≤L2≤22mm. This ensures that the battery pack has a high energy density while providing sufficient space for storing gas in the pouch cell.

[0052] like Figure 1 In some embodiments, a first rounded corner 413 is provided at the connection between the first sealing segment 4111 and the second sealing segment 4112, and a second rounded corner 414 is provided at the connection between the second sealing segment 4112 and the third sealing segment 4113, wherein the radius of the second rounded corner 414 is greater than the radius of the first rounded corner 413.

[0053] In conjunction with the aforementioned embodiments, after defining the structure of the top sealing sub-region 411 using L1, L2, and a, the applicant discovered that after a certain number of charge-discharge cycles (hereinafter referred to as cycles) of the pouch cell, stress concentration may occur at the corner between the first sealing section 4111 and the second sealing section 4112, or at the corner between the second sealing section 4112 and the third sealing section 4113, affecting the uniformity of stress on the sealing edge area 410. During the cycling process of the pouch cell, the generated gas during the cycle will continuously tear the thermoplastic connection structure of the top sealing sub-region 411 (especially at the two corner positions mentioned above). Under long-term cumulative action, the thermoplastic connection structure is torn open, leading to encapsulation failure and thus causing leakage of the pouch cell.

[0054] To avoid the above problems, this embodiment provides a first rounded corner 413 at the corner between the first sealing segment 4111 and the second sealing segment 4112, and a second rounded corner 414 at the corner between the third sealing segment 4113 and the second sealing segment 4112.

[0055] After extensive experimentation, the applicant discovered that stress concentration is more likely to occur at the corner between the third seal segment 4113 and the second seal segment 4112, necessitating a larger radius for the second rounded corner 414. Furthermore, since the length of the second seal segment 4112 can be greater than the length of the first seal segment 4111, this provides a structural basis for designing a larger radius for the second rounded corner 414. Therefore, this embodiment allows for a larger radius for the second rounded corner 414, further reducing the risk of encapsulation failure in the top seal sub-region 411.

[0056] like Figure 1 In some embodiments, the radius of the first fillet 413 is 10 mm to 18 mm.

[0057] For example, the radius of the first fillet 413 can be 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm or 18mm.

[0058] If the radius of the first rounded corner 413 is too small, the effect of improving stress concentration will be poor, and the risk of encapsulation failure at the corner between the first seal segment 4111 and the second seal segment 4112 will still be high. However, since the length of the first seal segment 4111 along the second direction is relatively short, it is also difficult to form a structure with an excessively large radius for the first rounded corner 413.

[0059] Therefore, in this embodiment, the radius of the first rounded corner 413 is limited to 10mm to 18mm. On the basis of ensuring that the top sealing sub-region 411 can form a preset structure, it can at least improve the situation of stress concentration at the corner between the first sealing segment 4111 and the second sealing segment 4112, thereby reducing the risk of encapsulation failure at the corner between the first sealing segment 4111 and the second sealing segment 4112.

[0060] like Figure 1 In some embodiments, the radius of the second fillet 414 is 12 mm to 20 mm.

[0061] For example, the radius of the second fillet 414 can be 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm or 20mm.

[0062] If the radius of the second rounded corner 414 is too small, the effect of improving stress concentration will be poor, and the risk of encapsulation failure at the corner between the third seal segment 4113 and the second seal segment 4112 will still be high. Due to the limitations of the lengths of the second seal segment 4112 and the third seal segment 4113, it is also difficult to form a structure with an excessively large radius for the second rounded corner 414.

[0063] Therefore, in this embodiment, the radius of the second rounded corner 414 is limited to 12mm to 20mm. While ensuring that the top sealing sub-region 411 can form a preset structure, it can improve the situation of stress concentration at the corner between the third sealing segment 4113 and the second sealing segment 4112, thereby reducing the risk of encapsulation failure at the corner between the third sealing segment 4113 and the second sealing segment 4112.

[0064] like Figure 1 In some embodiments, the first rounded corner 413 has a first starting end 4131 near the first sealing segment 4111, the second rounded corner 414 has a second ending end 4142 near the third sealing segment 4113, the distance between the first starting end 4131 and the second ending end 4142 along the first direction is L4, the distance between the extension line of the second sealing segment 4112 to the third sealing segment 4113 and the second ending end 4142 along the first direction is L3, and L3 / L4≥0.3.

[0065] For example, the first rounded corner 413 also has a first end 4132 near the second end segment 4112, and the second rounded corner 414 also has a second beginning end 4141 near the second end segment 4112.

[0066] To further improve the stress concentration in the top seal area 411, this embodiment optimizes the relative curvature between the first rounded corner 413 and the second rounded corner 414, limiting the relationship between L3 and L4 to L3 / L4≥0.3, so that the stress in the top seal area 411 is more uniform.

[0067] Figure 3 A schematic diagram of the first type of pouch cell before cycling is shown. Figure 3 The bare cell 100 includes a ternary high-nickel positive electrode paired with a silicon carbide negative electrode, and meets the design requirements for high energy density. The radii of the first rounded corner 413 and the second rounded corner 414 of the pouch cell are both no more than 10 mm. Figure 3 The darker area is the top seal area 411, and the white area is the air bag space 431. At this time, the sealing strength of the top seal area 411 at the second rounded corner 414 is normal.

[0068] Figure 4 A schematic diagram of the first type of pouch cell cycling at 45°C to 550cls is shown. Figure 4 The top seal area 411 at the second rounded corner 414 no longer meets the process requirements, that is, the top seal area 411 at the second rounded corner 414 has failed and leakage has occurred.

[0069] Figure 5 A schematic diagram of the second type of pouch cell before cycling is shown. Figure 5 Bare cells 100 and Figure 3 The bare cell 100 is the same. The radius of the first rounded corner 413 of this pouch cell is 13mm, and the radius of the second rounded corner 414 is 15mm. The values ​​of L3 and L4 are 3.42mm and 10.3mm respectively, and the ratio of L3 to L4 is 0.332. At this time, the encapsulation strength of the top seal area 411 at the second rounded corner 414 is normal.

[0070] Figure 6 A schematic diagram of the second type of pouch cell cycling at 45°C for 800 cls is shown. Figure 6 The encapsulation strength of the top seal sub-region 411 at the second rounded corner 414 no longer meets the process requirements; that is, the encapsulation of the top seal sub-region 411 at the second rounded corner 414 has failed, and leakage has occurred. It can be seen that by optimizing the radius of the first rounded corner 413, the radius of the second rounded corner 414, and L3 / L4, the safety, reliability, and cycle life of the pouch cell can be effectively improved.

[0071] like Figure 1 In some embodiments, the dimension of the first sealing segment 4111 along the second direction is defined as the width b of the top sealing sub-region 411, where 4mm ≤ b ≤ 12mm.

[0072] For example, b can be 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm or 12mm.

[0073] For example, the width of the edge banding area 410 is uniform, that is, the width of the edge banding area 410 is always b.

[0074] If b is too large, it may reduce the air bag space 431, which may lead to the failure of the top sealing sub-area 411 and increase the risk of leakage of the soft-pack battery cell. If b is too small, the connection reliability may be reduced due to the small heat fusion area in the top sealing sub-area 411, which may also lead to the failure of the top sealing sub-area 411 and increase the risk of leakage of the soft-pack battery cell.

[0075] To avoid the above problems, in this embodiment, the width b of the top sealing sub-area 411 is limited to 4mm≤b≤12mm to ensure that the gas storage space of the air bag space 431 is sufficient and the top sealing sub-area 411 has high sealing reliability, thereby reducing the risk of sealing failure of the sealing edge area 410 and leakage of soft-pack battery cells.

[0076] In some embodiments, side 500 includes a first side 510 and a second side 520; along a first direction, the distance between the conductive sheet 200 and the first side 510 is greater than the distance between the conductive sheet 200 and the second side 520, and the top sealing sub-region 411 is at least disposed between the conductive sheet 200 and the first side 510.

[0077] For example, when the space between the conductive sheet 200 and the second side surface 520 is large, a top sealing sub-region 411 can also be provided between the conductive sheet 200 and the second side surface 520.

[0078] by Figure 1 Taking the structure and orientation shown as an example, if the center line of the conductive sheet 200 along the second direction deviates to the right from the center line of the end 110 along the second direction, it is possible that the space on the right side of the conductive sheet 200 is smaller, resulting in a shorter length of the third sealing segment 4113 on the right side of the conductive sheet 200. This would prevent the radius of the second rounded corner 414 from reaching 12mm. In this case, the radius of the second rounded corner 414 on that side must be reduced to ensure a uniform width of the sealing area 410. However, since the space on the left side of the conductive sheet 200 is sufficient, a top sealing sub-area 411 as described in the previous embodiment can be formed. This can improve the stress concentration situation in the sealing area 410 as a whole, thereby reducing the risk of encapsulation failure in the sealing area 410.

[0079] In some embodiments, along the first direction, the distance between the conductive sheet 200 and the first side surface 510 is equal to the distance between the conductive sheet 200 and the second side surface 520, and a top sealing sub-region 411 is provided on both sides of the conductive sheet 200 along the first direction.

[0080] The distance between the conductive sheet 200 and the first side surface 510 is equal to the distance between the conductive sheet 200 and the second side surface 520. That is, the center line of the conductive sheet 200 along the second direction is aligned with the center line of the end 110 along the second direction. At this time, the conductive sheet 200 has sufficient space on both sides along the first direction to form the top sealing sub-region 411 as described in the previous embodiment. This can better improve the stress concentration situation of the sealing area 410 as a whole, thereby reducing the risk of encapsulation failure in the sealing area 410.

[0081] Based on the same inventive concept and in conjunction with the description of the pouch cells in the above embodiments, this embodiment provides a battery module that has the corresponding technical effects of the pouch cells in the above embodiments, which will not be repeated here.

[0082] A battery module includes pouch cells as described in the above embodiments.

[0083] It should be noted that some embodiments of this application have been described above. Other embodiments are within the scope of the appended claims.

[0084] The various embodiments in this application are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0085] The description in this application is given for illustrative purposes and is not intended to be exhaustive or to limit the application to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described to better illustrate the principles and practical application of this application and to enable those skilled in the art to understand this application and design various embodiments with various modifications suitable for a particular purpose.

[0086] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this application is limited to these examples; under the concept of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the embodiments of this application as described above, which are not provided in detail for the sake of brevity.

[0087] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications and variations of these embodiments will be apparent to those skilled in the art from the foregoing description.

[0088] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. A pouch cell, characterized in that, The pouch cell has two sides disposed opposite to each other along a first direction, and the pouch cell includes: A bare battery cell has two tabs arranged opposite each other along a second direction; A conductive sheet is electrically connected to the electrode tab; The flexible encapsulation film includes two half-films respectively disposed on opposite sides of the bare battery cell along a third direction, the two half-films forming a receiving cavity, and the bare battery cell disposed within the receiving cavity; a conductive sheet extends out of the receiving cavity, and a sealant is disposed between the half-film and the conductive sheet; the two half-films are heat-fused together and the half-films are heat-fused together with the sealant to form a sealing area surrounding the bare battery cell; the sealing area includes a top sealing sub-area located on one side of the conductive sheet along a first direction, the top sealing sub-area including a first sealing segment, a second sealing segment, and a third sealing segment connected end to end in sequence, the end of the first sealing segment away from the second sealing segment extending to the sealant, and the end of the third sealing segment away from the second sealing segment extending to the side; the first direction, the second direction, and the third direction are mutually perpendicular; The included angle between the second and third sealing segments is α, where 105° ≤ α ≤ 150°.

2. The soft-pack battery cell according to claim 1, characterized in that, The bare cell includes a body, the tab is formed at the end of the body, the first sealing section and the third sealing section are both parallel to the edge of the end, the length of the top sealing sub-region along the first direction is L1, the distance between the edge of the first sealing section away from the bare cell and the edge of the third sealing section near the bare cell along the second direction is L2, 30mm≤L1≤40mm, and 12mm≤L2≤22mm.

3. The soft-pack battery cell according to claim 1, characterized in that, A first rounded corner is provided at the connection between the first sealing segment and the second sealing segment, and a second rounded corner is provided at the connection between the second sealing segment and the third sealing segment. The radius of the second rounded corner is greater than the radius of the first rounded corner.

4. The soft-pack battery cell according to claim 3, characterized in that, The radius of the first fillet is 10mm to 18mm.

5. The soft-pack battery cell according to claim 3, characterized in that, The radius of the second fillet is 12mm to 20mm.

6. The soft-pack battery cell according to claim 3, characterized in that, The first rounded corner has a first starting end near the first sealing segment, the second rounded corner has a second ending end near the third sealing segment, the distance between the first starting end and the second ending end along the first direction is L4, the distance between the extension line of the second sealing segment to the third sealing segment and the second ending end along the first direction is L3, and L3 / L4≥0.

3.

7. The soft-pack battery cell according to claim 1, characterized in that, The dimension of the first sealing segment along the second direction is defined as the width b of the top sealing sub-region, where 4mm ≤ b ≤ 12mm.

8. The soft-pack battery cell according to claim 1, characterized in that, The side surface includes a first side surface and a second side surface; along the first direction, the distance between the conductive sheet and the first side surface is greater than the distance between the conductive sheet and the second side surface, and the top sealing sub-region is at least disposed between the conductive sheet and the first side surface.

9. The soft-pack battery cell according to claim 1, characterized in that, The side surface includes a first side surface and a second side surface; along the first direction, the distance between the conductive sheet and the first side surface is equal to the distance between the conductive sheet and the second side surface, and the top sealing sub-area is provided on both sides of the conductive sheet along the first direction.

10. A battery module, characterized in that, Includes the pouch cell as described in any one of claims 1 to 9.

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