Pouch battery and battery assembly

Abstract

Disclosed in the present application are a pouch battery and a battery assembly. The pouch battery comprises: a housing, a battery cell and tabs. The housing comprises an encapsulation body and a top sealing edge, the encapsulation body being provided with an accommodating cavity. The top sealing edge comprises a sealed portion and unsealed portions, the sealed portion being connected to the encapsulation body, the unsealed portions being connected to the sealed portion, the unsealed portions comprising first unsealed sub-portions and second unsealed sub-portions, and the first unsealed sub-portions being provided with clearance recesses. The tabs are connected to the battery cell and extend out of the accommodating cavity. The portions of the tabs located outside the first unsealed sub-portions and the second unsealed sub-portions are first tab portions. In the length direction of the top sealing edge, the size of the first tab portions is not greater than the size of the clearance recesses. Therefore, the first tab portions can be bent towards the clearance recesses, and part of partial projections of the first tab portions is located within the range of the clearance recesses, that is, the space occupied by the first tab portions partially overlaps the space occupied by the unsealed portions, thereby reducing the space occupied by the pouch battery in the length direction thereof and improving the energy density of the pouch battery.

Description

pouch batteries and battery packs Technical Field

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

[0002] In some technologies, to prevent molten adhesive from overflowing during the sealing of pouch cells, an unsealed area is left outside the sealed edge to accommodate any overflowing adhesive. To improve the energy density of pouch cells, the tabs are bent towards the outer casing during installation to reduce the cell's length. However, because the aluminum layer inside the aluminum-plastic film is exposed at the cut edge after cutting, to prevent short circuits caused by contact between the tabs and the aluminum layer, the tabs need to be offset from the unsealed portion in the width direction of the top sealed edge during bending. This increases the length of the pouch cell, thus reducing its energy density. Summary of the Invention

[0003] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a pouch cell that can improve the energy density of pouch cells.

[0004] This application also provides a battery assembly including the aforementioned pouch cell battery.

[0005] A pouch battery according to a first aspect embodiment of this application includes: a casing, a cell, and tabs.

[0006] The housing includes a packaging body and a top sealing edge. The packaging body has a receiving cavity. The top sealing edge includes a sealed portion and an unsealed portion. The sealed portion is connected to the packaging body, and the unsealed portion is connected to the side of the sealed portion opposite to the packaging body. The unsealed portion includes a first sub-unsealed portion and a second sub-unsealed portion distributed along its own thickness. The first sub-unsealed portion has a clearance groove that extends to the surface of the first sub-unsealed portion opposite to the sealed portion. The battery cell is located within the receiving cavity. The electrode tab is connected to the battery cell and extends out of the receiving cavity through the first sub-unsealed portion and the second sub-unsealed portion. The portion of the electrode tab located outside the first sub-unsealed portion and the second sub-unsealed portion is the first electrode tab portion. In the length direction of the top sealing edge, the size of the first electrode tab portion is not greater than the size of the clearance groove.

[0007] The soft-pack battery according to the embodiments of this application has at least the following beneficial effects:

[0008] In this embodiment, the first unsealed portion has a clearance groove, and the size of the first tab is no larger than the size of the clearance groove along the length of the top sealing edge. Therefore, when assembling the pouch battery with other components, the first tab can be bent towards the clearance groove, and the portion of the first tab projected along the thickness of the top sealing edge is within the clearance groove, thereby reducing the risk of contact between the tab and the first unsealed portion during use. It can be understood that, compared to conventional technology, in this embodiment, a portion of the projection of the first tab is within the clearance groove, meaning that the space occupied by the first tab and the unsealed portion along the width of the top sealing edge overlaps, thus reducing the space occupied by the pouch battery itself and increasing its energy density.

[0009] According to some embodiments of this application, the portion of the electrode ear located between the first unsealed portion and the second unsealed portion is the second electrode ear portion, and the projection of the second electrode ear portion is located within the range of the clearance groove along the thickness direction of the top sealing edge.

[0010] According to some embodiments of this application, the pouch battery further includes a first insulating adhesive layer, which is located within the vented groove and covers the second electrode tab.

[0011] According to some embodiments of this application, the first unsealed portion includes a first insulating layer, a first metal layer, and a second insulating layer bonded together along its own thickness direction. The first insulating layer has a first notch, and the first metal layer has a second notch aligned with the first notch. The clearance groove includes the first notch and the second notch, and the second insulating layer forms the first insulating adhesive layer at the portion corresponding to the second notch.

[0012] According to some embodiments of this application, the second unsealed portion includes a third insulating layer, a second metal layer, and a fourth insulating layer bonded together along its own thickness direction. The third insulating layer has a third notch at a position corresponding to the second electrode tab, the second metal layer has a fourth notch aligned with the third notch, and the fourth insulating layer covers the second electrode tab.

[0013] According to some embodiments of this application, the first unsealed portion has a plurality of the aforementioned air-avoiding grooves, the soft-pack battery includes a plurality of the aforementioned tabs, the plurality of air-avoiding grooves are respectively arranged in a one-to-one correspondence with the plurality of the aforementioned tabs, the region of the unsealed portion located between the adjacent air-avoiding grooves has a fifth notch that extends through its own thickness direction, the fifth notch extends to the edge of the unsealed portion and extends to the air-avoiding groove;

[0014] The two outermost clearance slots along the length of the top sealing edge are called outer clearance slots. The unsealed part also has a sixth notch that extends through the two outer clearance slots in the area where they are opposite to each other. Each of the sixth notches extends to the edge of the unsealed part and to the outer clearance slot adjacent to itself.

[0015] According to some embodiments of this application, along the width direction of the top sealing edge, the dimension of the unsealed portion is L3, the dimension of the clearance groove is L4, and 7 / 8≤L4 / L3≤9 / 10.

[0016] A battery assembly according to a second aspect embodiment of this application includes: a circuit board and a pouch battery according to a first aspect embodiment. A first tab is bent toward the top sealing edge and electrically connected to the circuit board. A portion of the projection of the first tab lies within the clearance groove along the thickness direction of the top sealing edge.

[0017] The battery assembly according to the embodiments of this application has at least the following beneficial effects:

[0018] The pouch cell using the first aspect embodiment has a first unsealed portion with a clearance groove, and the size of the first tab is no larger than the size of the clearance groove along the length of the top sealing edge. The first tab is bent toward the clearance groove, and the portion of the projection of the first tab in the thickness direction of the top sealing edge is located within the clearance groove, thereby reducing the risk of the tab contacting the first unsealed portion during use. It is understood that, compared to conventional technology, in this embodiment, a portion of the projection of the first tab is located within the clearance groove, meaning that the space occupied by the first tab and the unsealed portion in the width direction of the top sealing edge partially overlaps, thereby reducing the space occupied by the pouch cell itself, increasing the energy density of the pouch cell, and thus increasing the energy density of the battery assembly in this embodiment.

[0019] According to some embodiments of this application, the top sealing edge is bent toward the encapsulation body, and the circuit board has opposite connecting surfaces along the length of the pouch battery, with the first electrode tab connected to either of the connecting surfaces.

[0020] According to some embodiments of this application, the first electrode ear is bent to form a bent portion, and the first electrode ear includes a plurality of bent portions.

[0021] According to some embodiments of this application, in the width direction of the top sealing edge, the first electrode ear is spaced apart from the side wall of the clearance groove.

[0022] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0023] The present application will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0024] Figure 1 is a schematic diagram of a common battery assembly in the prior art;

[0025] Figure 2 is a schematic diagram of the structure of a soft-pack battery according to a first aspect embodiment of this application;

[0026] Figure 3 is an enlarged schematic diagram of region A in Figure 2;

[0027] Figure 4 is a schematic diagram of the structure of the soft-pack battery after the tabs in Figure 2 are bent.

[0028] Figure 5 is an enlarged schematic diagram of region B in Figure 4;

[0029] Figure 6 is a schematic diagram of the structure of a second type of soft-pack battery according to the first aspect of this application;

[0030] Figure 7 is a schematic diagram of the structure of a third type of soft-pack battery according to the first aspect of this application;

[0031] Figure 8 is a partial cross-sectional view of the pouch cell in Figure 4;

[0032] Figure 9 is an enlarged schematic diagram of region C in Figure 8;

[0033] Figure 10 is a schematic diagram of the structure of a fourth type of soft-pack battery according to the first aspect of this application;

[0034] Figure 11 is a schematic diagram of the structure of a first type of battery assembly according to a second aspect embodiment of this application;

[0035] Figure 12 is a schematic diagram of the structure of a second type of battery assembly according to a second aspect embodiment of this application;

[0036] Figure 13 is a schematic diagram of the structure of a third type of battery assembly according to the second aspect of this application.

[0037] Reference numerals: 100 for outer casing, 110 for encapsulation body, 101 for top sealing edge, 120 for sealing portion, 130 for unsealed portion, 131 for first unsealed portion, 1301 for clearance groove, 1302 for fifth notch, 1303 for sixth notch, 1311 for first insulating layer, 13111 for first notch, 1312 for first metal layer, 1312 for second notch, 1313 for second unsealed portion, 132 for third insulating layer, 1321 for third notch, 13211 for third metal layer, 1322 for fourth notch, 13221 for fourth insulating layer; 200 for tab, 210 for first tab portion, 211 for bent portion, 220 for second tab portion; 300 for first insulating adhesive layer, 400 for second insulating adhesive layer, 500 for circuit board. Detailed Implementation

[0038] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0039] In the description of this application, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0040] In the description of this application, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0041] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0042] In some technologies, to prevent molten adhesive from overflowing during the sealing of pouch cells, an unsealed area is reserved outside the sealed edge to accommodate any overflowing adhesive. To improve the energy density of pouch cells, the tabs are bent towards the outer casing during installation to reduce the cell's length. However, after the aluminum-plastic film is cut, the aluminum layer inside the film is exposed at the cut edge. To prevent the tabs from contacting the aluminum layer and causing a short circuit, the tabs need to be offset from the unsealed portion in the width direction of the top sealed edge during bending (as shown in Figure 1). This increases the length of the pouch cell, thus reducing its energy density.

[0043] Based on the above problems, the first aspect of this application proposes a pouch battery that can improve the energy density of the pouch battery. The embodiments of this application will be explained and illustrated with reference to Figures 2 to 13. It should be noted that in the figures, the length direction refers to the length direction of the pouch battery, the width direction refers to the length direction of the top seal, and the thickness direction refers to the thickness direction of the pouch battery. In the following text, the width direction of the top seal corresponds to the length direction of the pouch battery when the top seal is not folded, the thickness direction of the top seal corresponds to the thickness direction of the pouch battery when the top seal is not folded, and the length direction of the top seal corresponds to the width direction of the pouch battery.

[0044] Referring to Figures 2 to 9, Figure 2 is a structural schematic diagram of a pouch battery according to the first aspect of this application, Figure 3 is an enlarged schematic diagram of region A in Figure 2, Figure 4 is a structural schematic diagram of the pouch battery in Figure 2 after the tabs are bent, Figure 5 is an enlarged schematic diagram of region B in Figure 4, Figure 6 is a structural schematic diagram of a second type of pouch battery according to the first aspect of this application, Figure 7 is a structural schematic diagram of a third type of pouch battery according to the first aspect of this application, Figure 8 is a partial cross-sectional view of the pouch battery in Figure 4, and Figure 9 is an enlarged schematic diagram of region C in Figure 8. The pouch battery of this embodiment includes: a casing 100, a battery cell, and tabs 200.

[0045] The outer shell 100 is formed, for example, by folding and sealing an aluminum-plastic film, but is not limited thereto. The outer shell 100 can also be made of composite materials formed by other metal layers and non-metals. Unless otherwise specified, aluminum-plastic film is used as an example in this application. The outer shell 100 includes a packaging body 110 and a top sealing edge 101. The top sealing edge 101 includes a sealing portion 120 and an unsealed portion 130 (as shown in FIG. 3). The packaging body 110 has a receiving cavity. The sealing portion 120 is connected to the packaging body 110, and the unsealed portion 130 is connected to the side of the sealing portion 120 facing away from the packaging body 110. The unsealed portion 130 includes a first sub-unsealed portion 131 and a second sub-unsealed portion 132 distributed along its own thickness direction. The first sub-unsealed portion 131 has a clearance groove 1301, which extends to the surface of the first sub-unsealed portion 131 facing away from the sealing portion 120. The battery cell is located within the receiving cavity. A tab 200 is connected to the battery cell and extends out of the receiving cavity between the first unsealed portion 131 and the second unsealed portion 132. The portion of the tab 200 located outside the first unsealed portion 131 and the second unsealed portion 132 is the first tab portion 210. In the length direction of the top sealing edge, the size of the first tab portion 210 is not greater than the size of the clearance groove 1301. For example, in the length direction of the top sealing edge 101, the size of each first tab portion 210 is L1, and the size of each clearance groove 1301 is L2, where 0 < L2 - L1 ≤ 2 mm.

[0046] Specifically, when assembling the soft-pack battery with other components, the first tab 210 can be bent toward the clearance groove 1301 (as shown in Figure 5), and the portion of the first tab 210 projected in the thickness direction of the top sealing edge 101 is located within the clearance groove 1301 (as shown in Figures 8 and 9), thereby reducing the risk of the tab 200 coming into contact with the first unsealed portion 131 during use. It is understood that, compared with traditional technology, in this embodiment, a portion of the projection of the first tab 210 is located within the clearance groove 1301, that is, the space occupied by the first tab 210 and the unsealed portion 130 in the width direction of the top sealing edge 101 coincides, thereby reducing the space occupied by the pouch battery. For example, when the top sealing edge 101 is not folded, the space occupied by the first tab 210 and the unsealed portion 130 in the width direction of the top sealing edge 101 coincides, thereby reducing the space occupied by the pouch battery in its own length direction. When the top sealing edge 101 is bent toward the encapsulation body 110, and the width direction of the top sealing edge 101 corresponds to the thickness direction of the pouch battery, the space occupied by the pouch battery in its own thickness direction can be reduced, thereby increasing the energy density of the pouch battery.

[0047] It should be noted that the dashed lines in Figures 2 to 5 are not to be interpreted as the actual outline of the pouch battery, but are only used to more clearly show the positions of the sealed portion 120 and the unsealed portion 130. Furthermore, in this embodiment, the number of clearance slots 1301 is not limited; it can be one, two, or more, depending on the requirements. Specifically, a pouch battery typically includes at least two tabs 200. For small-sized pouch batteries, since the distance between their two tabs 200 is relatively small, the first unsealed portion 131 can be provided with only one clearance slot 1301 (as shown in Figure 7), with one clearance slot 1301 corresponding to the two tabs 200. For some larger-sized pouch batteries, since the distance between their two tabs 200 is relatively large, the first unsealed portion 131 can be provided with two clearance slots 1301, that is, one tab 200 corresponds to one clearance slot 1301. For some pouch batteries with multiple tabs 200, multiple clearance slots 1301 can be provided accordingly. Furthermore, in this embodiment, the position of the clearance groove 1301 is not limited. For example, when only one clearance groove 1301 is provided, the clearance groove 1301 can be located between the two tabs 200 (as shown in Figure 6). Alternatively, according to the installation requirements of the soft-pack battery, the clearance groove 1301 can be located at one edge of the first unsealed part 131 in the length direction of the top sealing edge 101. Then, the flexibility of the tab 200 itself is used to bend the tab 200 toward the clearance groove 1301, so that the tab 200 is bent toward the clearance groove 1301.

[0048] It should also be noted that a portion of the projection of the first electrode ear 210 is located within the clearance groove 1301, including two cases: a portion of the first electrode ear 210 is inserted into the clearance groove 1301, or the first electrode ear 210 is located outside the clearance groove 1301, which is set according to the usage requirements.

[0049] Furthermore, the relative positional relationship between the first unsealed portion 131 and the second unsealed portion 132 in the accompanying drawings should not be interpreted as the only limitation of this embodiment, as long as the first unsealed portion 131 and the second unsealed portion 132 are distributed along the thickness direction of the unsealed portion 130.

[0050] Referring to Figures 8 and 9, in some embodiments, the portion of the tab 200 located between the first unsealed portion 131 and the second unsealed portion 132 is designated as the second tab portion 220. Along the thickness direction of the top sealing edge 101, the projection of the second tab portion 220 lies within the range of the clearance groove 1301, meaning the position of the clearance groove 1301 corresponds to the position where the tab 200 protrudes. Therefore, when the tab 200 is bent, it can be bent along a crease extending in its own width direction, thereby reducing the space occupied by the tab 200 in the width direction of the pouch battery and thus improving the energy density of the pouch battery.

[0051] Referring to Figure 5, in some embodiments, the pouch battery further includes a first insulating adhesive layer 300, which is located within the recessed groove 1301 and covers the second tab 220. Specifically, as mentioned above, after the aluminum-plastic film is cut, the inner aluminum layer will be exposed from the cut edge; that is, in this embodiment, the aluminum layer will be exposed from the inner wall of the recessed groove 1301. To improve the safety of the pouch battery, this embodiment further includes the first insulating adhesive layer 300, which is located within the recessed groove 1301 and covers the second tab 220, thereby preventing the aluminum layer exposed from the inner wall of the recessed groove 1301 from contacting the tab 200.

[0052] Referring to Figures 5 to 9, in some embodiments, the first unsealed portion 131 includes a first insulating layer 1311, a first metal layer 1312, and a second insulating layer 1313 bonded together along its thickness direction. For example, in this embodiment, the outer shell 100 is made of aluminum-plastic film. The first insulating layer 1311 is an insulating material such as a nylon layer or a PET layer (polyethylene terephthalate layer). The first metal layer 1312 is an aluminum layer. The second insulating layer 1313 is a PP layer (polypropylene layer). The first insulating layer 1311 has a first notch 13111. The first metal layer 1312 has a second notch 13121 aligned with the first notch 13111 (refer to Figure 9). The clearance groove 1301 includes the first notch 13111 and the second notch 13121. The second insulating layer 1313 forms a second insulating adhesive layer 400 corresponding to the portion of the second notch 13121. That is, during the processing, a first notch 13111 and a second notch 13121 are formed on the nylon layer and aluminum layer of the aluminum-plastic film, respectively, and the PP layer at the corresponding positions of the first notch 13111 and the second notch 13121 is retained as the first insulating adhesive layer 300, without the need to use other components as the first insulating adhesive layer 300. This not only reduces the processing cost of the soft pack battery, but also improves the processing efficiency of the soft pack battery by eliminating the step of setting the first insulating adhesive layer 300.

[0053] Referring to Figures 8 and 9, based on the above embodiment, the second unsealed portion 132 includes a third insulating layer 1321, a second metal layer 1322, and a fourth insulating layer 1323 bonded together along its thickness direction. Similarly, taking the outer shell 100 as an aluminum-plastic film as an example, the third insulating layer 1321 is an insulating material such as a nylon layer or a PET layer (polyethylene terephthalate layer). The second metal layer 1322 is an aluminum layer, and the fourth insulating layer 1323 is a PP layer (polypropylene layer). The third insulating layer 1321 has a third notch 13211 at a position corresponding to the second electrode tab 220, the second metal layer 1322 has a fourth notch 13221 aligned with the third notch 13211, and the fourth insulating layer 1323 covers the second electrode tab 220. Specifically, the portion of the fourth insulating layer 1323 corresponding to the second tab 220 is defined as the second insulating adhesive layer 400. The second insulating adhesive layer 400 covers the position of the second tab 220 corresponding to the second notch 13121, thus preventing the tab 200 from contacting the second metal layer 1322 and causing a short circuit, thereby improving the safety of the pouch battery during use. Specifically, in this embodiment, a portion of the fourth insulating layer 1323 itself is used as the second insulating adhesive layer 400. Taking aluminum-plastic film as an example, in this embodiment, a portion of the PP layer is used as the second insulating adhesive layer 400, eliminating the need for other insulating adhesives (such as the tab adhesive with a protruding unsealed portion 130 at the protruding part of the tab 200 in the prior art). This not only reduces the processing cost of the pouch battery but also improves the processing efficiency of the pouch battery by eliminating the tab adhesive setting step.

[0054] Furthermore, it is understood that in this embodiment, there is no need to provide tabs protruding from the unsealed portion 130 as in the prior art. Therefore, in some applications, the tabs 200 can be folded along the edge of the unsealed portion 130, thereby significantly reducing the length of the pouch battery and thus increasing the energy density of the pouch battery.

[0055] Referring to Figure 10, which is a schematic diagram of the structure of a fourth type of soft-pack battery according to the first aspect of this application, in some embodiments, the first unsealed portion 131 has a plurality of clearance slots 1301. The soft-pack battery includes a plurality of tabs 200. The plurality of clearance slots 1301 are arranged in a one-to-one correspondence with the plurality of tabs 200. The region of the unsealed portion 130 located between adjacent clearance slots 1301 has a fifth notch 1302 extending through its own thickness direction. The fifth notch extends to the edge of the unsealed portion 130 and extends to the clearance slot 1301. In the length direction of the top sealing edge 101, the two outermost clearance slots 1301 are outer clearance slots. The region of the unsealed portion 130 located between the two outer clearance slots also has a sixth notch 1303 extending through its own thickness direction. Each sixth notch 1303 extends to the edge of the unsealed portion 130 and extends to the outer clearance slot adjacent to itself. That is, the unsealed portion 130 only retains the insulating layer corresponding to the tab 200 (the second insulating layer 1313 of the first sub-unsealed portion 131, and the fourth insulating layer 1323 of the second sub-unsealed portion 132, which corresponds to the PP layer), in order to reduce the weight of the pouch battery. Furthermore, since both the second insulating layer 1313 and the fourth insulating layer 1323 are made of flexible materials, the tab 200 can be folded along the edge of the sealing portion 120, thereby reducing the length of the pouch battery and increasing its energy density.

[0056] In some embodiments, along the width direction of the top sealing edge 101, the dimension of the unsealed portion 130 is L3, and the dimension of the clearance groove 1301 is L4, where 7 / 8 ≤ L4 / L3 ≤ 9 / 10. Specifically, it can be understood that the larger the dimension of the clearance groove 1301 in the width direction of the top sealing edge 101, the shorter the length of the pouch battery after bending the tab 200. However, a larger clearance groove 1301 also means that the sidewall of the clearance groove 1301 is closer to the sealing portion 120, which can easily lead to the risk of accidentally cutting the sealing portion 120. Based on this, in this embodiment, the dimension of the clearance groove 1301 in the length direction of the top sealing edge 101 is set within a suitable range, so that the dimension of the clearance groove 1301 in the length direction of the top sealing edge 101 accounts for 7 / 8 to 9 / 10 of the dimension of the first unsealed portion 131, thereby reducing the risk of accidentally cutting the sealing portion 120 while minimizing the length of the pouch battery.

[0057] Referring to Figures 11 and 12, Figure 11 is a structural schematic diagram of a first type of battery assembly according to a second aspect embodiment of this application, and Figure 12 is a structural schematic diagram of a second type of battery assembly according to a second aspect embodiment of this application. The battery assembly of the second aspect embodiment of this application includes: a circuit board 500 and a pouch battery according to the first aspect embodiment. A first tab 210 is bent toward the top sealing edge 101 and electrically connected to the circuit board 500. Along the thickness direction of the top sealing edge 101, a portion of the projection of the first tab 210 is located within the clearance groove 1301. This reduces the risk of the tab 200 contacting the first unsealed portion 131 during use. For example, in some embodiments, when the top sealing edge 101 is not folded, that is, when the width direction of the top sealing edge 101 corresponds to the length direction of the pouch battery, the space occupied by the first tab 210 and the unsealed portion 130 in the width direction of the top sealing edge 101 partially overlaps, thereby reducing the space occupied by the pouch battery in its own length direction (as shown in Figure 11). In some embodiments, the top sealing edge 101 is bent toward the encapsulation body 110, so that the width direction of the top sealing edge 101 corresponds to the thickness direction of the pouch battery. In the length direction of the pouch battery, the circuit board 500 has two connecting surfaces 510 arranged opposite to each other. The first tab 210 is bent toward the clearance groove 1301 and connected to either connecting surface 510. Since the clearance groove 1301 and the first tab 210 overlap in the width direction of the top sealing edge 101, that is, the clearance groove 1301 and the first tab 210 partially overlap in the thickness direction of the pouch battery, thereby reducing the space occupied by the pouch battery in its own thickness direction (as shown in Figure 12). It can be seen that when the top sealing edge 101 is bent toward the encapsulation body 110, the arrangement of the clearance groove 1301 can reduce the size of the battery assembly in the thickness direction of the pouch battery, thereby improving the energy density of the battery assembly in this embodiment.

[0058] It should be noted that this embodiment adopts all the technical features of the soft-pack battery of the first aspect embodiment. Therefore, this embodiment has all the beneficial effects brought by the first aspect embodiment, which will not be repeated here.

[0059] Referring to Figure 12, which is a schematic diagram of the structure of a third type of battery assembly according to a second aspect embodiment of the present application, in some embodiments, the first tab 210 is bent to form a bent portion 211. The first tab 210 includes multiple bent portions 211. That is, in this embodiment, the first tab 210 is bent multiple times to form multiple bent portions 211, thereby further reducing the overall length of the battery assembly and thus improving the energy density of the battery assembly.

[0060] In some embodiments, in the direction of the width of the top sealing edge 101, the first pole ear 210 is spaced from the side wall of the clearance groove 1301. For example, in the direction of the width of the top sealing edge 101, the gap L3 between the first pole ear 210 and the side wall of the clearance groove 1301 satisfies 0 < L3 ≤ 2 mm, so as to improve the safety of the soft-pack battery. Specifically, it can be understood that in the width direction of the top sealing edge 101, the first pole ear 210 and the side wall of the clearance groove 1301 are spaced apart, which can reduce the risk of short circuit caused by the contact between the first pole ear 210 and the side wall of the clearance groove 1301. However, too large a gap also means that the overlapping area between the first pole ear 210 and the unsealed part 130 is reduced, and the overall space occupied by the battery assembly is increased. Therefore, in this embodiment, it is set within a reasonable range, that is, the gap between the first pole ear 210 and the side wall of the clearance groove 1301 is greater than 0 and less than or equal to 2 mm, so as to make the battery assembly have a higher energy density on the premise of improving the safety of the battery assembly.

[0061] The electrical device according to the third aspect embodiment of the present application, the electrical device is, for example, an electronic device such as a mobile phone, a watch or a tablet, or an electric vehicle or a hybrid electric vehicle. The electrical device includes: the battery assembly according to the second aspect embodiment. The first sub-unsealed part 131 of the battery assembly has a clearance groove 1301, and in the length direction of the top sealing edge, the size of the first pole ear 210 is not greater than the size of the soft-pack battery. The first pole ear 210 is bent towards the first sub-unsealed part 131, and a part of the projection of the first pole ear 210 in the thickness direction of the top sealing edge 101 is located within the range of the clearance groove 1301, thereby reducing the risk of contact between the pole ear 200 and the first sub-unsealed part 131 during use. It can be known that, compared with the traditional technology, in this embodiment, a part of the projection of the first pole ear 210 is located within the range of the clearance groove 1301, that is, a part of the space occupied by the first pole ear 210 and the unsealed part 130 overlaps, so as to reduce the space occupied by the soft-pack battery, and further improve the energy density of the battery assembly to improve the battery life of the electrical device.

[0062] The embodiments of the present application have been described in detail above with reference to the drawings. However, the present application is not limited to the above embodiments. Within the scope of knowledge possessed by those of ordinary skill in the art to which the present application pertains, various changes can be made without departing from the purpose of the present application. In addition, in the description of the present application, the descriptions referring to terms such as "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

Claims

1. A pouch battery, including: The outer casing includes a packaging body and a top sealing edge. The packaging body has a receiving cavity. The top sealing edge includes a sealed portion and an unsealed portion. The sealed portion is connected to the packaging body, and the unsealed portion is connected to the side of the sealed portion opposite to the packaging body. The unsealed portion includes a first sub-unsealed portion and a second sub-unsealed portion distributed along its own thickness. The first sub-unsealed portion has a clearance groove that extends to the surface of the first sub-unsealed portion opposite to the sealed portion. The battery cell is located within the receiving cavity; A tab is connected to the battery cell and extends out of the receiving cavity between the first unsealed portion and the second unsealed portion. The portion of the tab located outside the first unsealed portion and the second unsealed portion is the first tab portion. In the length direction of the top sealing edge, the size of the first tab portion is not greater than the size of the clearance groove.

2. The soft-pack battery according to claim 1, wherein, The portion of the electrode ear located between the first unsealed portion and the second unsealed portion is the second electrode ear portion. Along the thickness direction of the top sealing edge, the projection of the second electrode ear portion is located within the range of the clearance groove.

3. The soft-pack battery according to claim 2, wherein, The pouch battery also includes a first insulating adhesive layer, which is located within the air-proof groove and covers the second electrode tab.

4. The soft-pack battery according to claim 3, wherein, The first unsealed portion includes a first insulating layer, a first metal layer and a second insulating layer bonded together along its thickness direction. The first insulating layer has a first notch, and the first metal layer has a second notch aligned with the first notch. The clearance groove includes the first notch and the second notch. The second insulating layer forms the first insulating adhesive layer at the portion corresponding to the second notch.

5. The pouch cell battery according to claim 4, wherein, The second unsealed portion includes a third insulating layer, a second metal layer, and a fourth insulating layer bonded together along its thickness direction. The third insulating layer has a third notch at a position corresponding to the second electrode tab. The second metal layer has a fourth notch aligned with the third notch. The fourth insulating layer covers the second electrode tab.

6. The pouch cell battery according to claim 4, wherein, The first unsealed portion has a plurality of the aforementioned air-avoiding grooves, and the soft-pack battery includes a plurality of the aforementioned tabs. The plurality of air-avoiding grooves are arranged in a one-to-one correspondence with the plurality of the aforementioned tabs. The region of the unsealed portion located between the adjacent air-avoiding grooves has a fifth notch that extends through the portion along its own thickness direction. The fifth notch extends to the edge of the unsealed portion and extends to the air-avoiding groove. The two outermost clearance slots along the length of the top sealing edge are called outer clearance slots. The unsealed part also has a sixth notch that extends through the two outer clearance slots in the area where they are opposite to each other. Each of the sixth notches extends to the edge of the unsealed part and to the outer clearance slot adjacent to itself.

7. The pouch cell battery according to claim 2, wherein, Along the width direction of the top sealing edge, the dimension of the unsealed part is L3, the dimension of the clearance groove is L4, and 7 / 8≤L4 / L3≤9 / 10.

8. Battery assembly, including: Circuit board; According to any one of claims 1 to 7, the first tab is bent toward the top sealing edge and electrically connected to the circuit board, and a portion of the projection of the first tab is located in the clearance groove along the thickness direction of the top sealing edge.

9. The battery assembly according to claim 8, wherein, The top sealing edge is bent toward the encapsulation body. In the length direction of the soft-pack battery, the circuit board has connecting surfaces that are arranged opposite to each other, and the first electrode tab is connected to either of the connecting surfaces.

10. The battery assembly according to claim 8, wherein, The first electrode ear is bent to form a bent portion, and the first electrode ear includes multiple bent portions.

11. The battery assembly according to claim 8, wherein, In the width direction of the top sealing edge, the first pole ear is spaced apart from the side wall of the clearance groove.

Images