Pouch battery and method for manufacturing pouch battery

Abstract

Provided in the present invention are a pouch battery and a method for manufacturing a pouch battery. The pouch battery comprises a battery cell, an aluminum laminated film packaging structure and an adhesive layer, wherein the aluminum laminated film packaging structure comprises a main body portion and an edge sealing portion; the main body portion is provided with a cavity, and a battery cell body is received in the cavity; and the edge sealing portion is connected to an outer edge of the main body portion, encircles the main body portion circumferentially, and seals the cavity. An outer edge of the edge sealing portion comprises a first side edge and a pressure relief area, wherein part of a tab passes through the first side edge, part of the pressure relief area is covered by the adhesive layer, and the remaining part of the pressure relief area is exposed outside the adhesive layer. In the pouch battery of the present invention, a pressure relief portion is created at an outer edge of the aluminum laminated film packaging structure, thereby reducing the risk of explosion of the pouch battery.

Description

Soft-pack battery and soft-pack battery manufacturing method Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a soft-pack battery and a method for manufacturing the soft-pack battery. Background Art

[0002] Currently, battery safety issues primarily manifest as fires and explosions caused by thermal runaway. To reduce the risk of battery explosion, hard-shell batteries are equipped with explosion-proof valves in the outer shell or top cover (which can be made of aluminum). When the internal pressure of the battery is high, the explosion-proof valve opens, allowing the high-temperature gases inside the battery to escape and prevent an explosion.

[0003] However, the core of the soft-pack battery is wrapped in an aluminum-plastic film, which is soft and difficult to install an explosion-proof valve on. Therefore, the soft-pack battery in the prior art does not have an explosion-proof valve, and the safety of the soft-pack battery needs to be improved.

[0004] Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a soft-pack battery with a low risk of explosion and high safety.

[0006] The present invention also provides a method for manufacturing the soft-pack battery.

[0007] According to the first aspect of the present invention, a soft-pack battery includes an electric cell, an aluminum-plastic film packaging structure and an adhesive layer. The electric cell includes an electric cell body and an electrode tab connected to each other. The aluminum-plastic film packaging structure includes: a main body, a cavity is provided inside the main body, and the electric cell body is accommodated in the cavity; an edge sealing portion, the edge sealing portion is connected to the outer edge of the main body, the edge sealing portion surrounds the main body, and the edge sealing portion seals the cavity, the outer edge of the edge sealing portion includes a first side edge and a pressure relief area, a portion of the electrode tab passes through the first side edge to the outside of the aluminum-plastic film packaging structure, two ends of the pressure relief area are respectively connected to the two ends of the first side edge, a portion of the pressure relief area is covered by the adhesive layer, and another portion of the pressure relief area is exposed outside the adhesive layer.

[0008] The soft-pack battery according to the embodiment of the first aspect of the present invention has at least the following beneficial effects: relative to the portion of the pressure relief area covered by the glue layer, the sealing effect of the portion of the pressure relief area not covered by the glue layer is weaker. Therefore, when the temperature and pressure inside the cavity are high, the portion of the pressure relief area not covered by the glue layer will be first flushed open by the high-temperature gas in the cavity, and the sealing of the portion of the pressure relief area not covered by the glue layer will fail first, and the high-temperature gas will be discharged out of the cavity. As the high-temperature gas is discharged, the pressure inside the cavity decreases, and the risk of the soft-pack battery exploding is lower. The soft-pack battery of the present invention constructs a pressure-relieving portion on the outer edge of the aluminum-plastic film packaging structure, thereby reducing the risk of the soft-pack battery exploding.

[0009] According to some embodiments of the present invention, the pressure relief area includes a second side, a third side, and a fourth side, the third side is arranged opposite to the first side, the second side is arranged opposite to the fourth side, the second side and the fourth side are respectively located on both sides of the first side, and the adhesive layer covers the second side, the third side, and the fourth side; the pressure relief area also includes: a first connecting edge, the two ends of the first connecting edge are respectively connected to the first side and the second side, the angle between any one of the first side and the second side and the first connecting edge is an obtuse angle, and the first connecting edge is exposed outside the adhesive layer; and / or, a second connecting edge, the two ends of the second connecting edge are respectively connected to the second The side edge is connected to the third side edge, and the angle between the second connecting edge and any one of the second side edge and the third side edge is an obtuse angle, and the second connecting edge is exposed outside the adhesive layer; and / or, the third connecting edge, the two ends of the third connecting edge are respectively connected to the third side edge and the fourth side edge, and the angle between the third side edge and any one of the fourth side edge and the third connecting edge is an obtuse angle, and the third connecting edge is exposed outside the adhesive layer; and / or, the fourth connecting edge, the two ends of the fourth connecting edge are respectively connected to the fourth side edge and the first side edge, and the angle between the first side edge and any one of the fourth side edge and the fourth connecting edge is an obtuse angle, and the fourth connecting edge is exposed outside the adhesive layer.

[0010] According to some embodiments of the present invention, the pressure relief zone includes the first connecting edge, the second connecting edge, the third connecting edge and the fourth connecting edge; the edge sealing portion is bent, and the bent edge sealing portion satisfies: the first connecting edge, the second connecting edge, the third connecting edge and the fourth connecting edge are all located on a first plane; at least one of the first side edge, the second side edge, the third side edge and the fourth side edge is located on a second plane, and the first plane and the second plane are parallel to each other.

[0011] According to some embodiments of the present invention, the pressure relief zone includes a first connecting edge, and the angle between any one of the first side edge and the second side edge and the second connecting edge is 135°; and / or, the pressure relief zone includes a second connecting edge, and the angle between any one of the second side edge and the third side edge and the second connecting edge is 135°; and / or, the pressure relief zone includes a third connecting edge, and the angle between any one of the third side edge and the fourth side edge and the second connecting edge is 135°; and / or, the pressure relief zone includes a fourth connecting edge, and the angle between the fourth side edge and any one of the first side edge and the second connecting edge is 135°.

[0012] According to some embodiments of the present invention, the battery cell is a laminated battery cell, and the battery cell includes the first connecting edge, the second connecting edge, the third connecting edge, and the fourth connecting edge. The battery cell is provided with four chamfers, and the four chamfers are respectively arranged corresponding to the first connecting edge, the second connecting edge, the third connecting edge, and the fourth connecting edge.

[0013] According to some embodiments of the present invention, the adhesive layer is an insulator.

[0014] According to some embodiments of the present invention, the adhesive layer is a solidified UV-curable adhesive.

[0015] According to some embodiments of the present invention, the soft-pack battery further includes a separator and an electrolyte, wherein the separator is located in the cavity, and the separator divides the cavity into two sub-chambers. Two battery cells are provided, and the two battery cells are respectively arranged in different sub-chambers. A part of the electrolyte is located in one of the sub-chambers, and another part of the electrolyte is located in the other sub-chamber. The separator is used to prevent the electrolyte from passing through.

[0016] According to some embodiments of the present invention, the aluminum-plastic film packaging structure is formed by interconnecting a first aluminum-plastic film and a second aluminum-plastic film, the central area of ​​the first aluminum-plastic film and the central area of ​​the second aluminum-plastic film are stacked to form the main body, and the peripheral area of ​​the first aluminum-plastic film and the peripheral area of ​​the second aluminum-plastic film are stacked and connected to each other to form a sealing edge; the soft-pack battery also includes a tab glue, which is connected to the tab, and the tab glue is sandwiched between the first aluminum-plastic film and the second aluminum-plastic film, and the tab glue is arranged at the first side.

[0017] According to the second embodiment of the present invention, the method for manufacturing a soft-pack battery includes the following steps: placing a battery cell between a first aluminum-plastic film and a second aluminum-plastic film, and connecting a portion of an edge of the first aluminum-plastic film and a portion of an edge of the second aluminum-plastic film; injecting an electrolyte into the battery cell, and then sealing the first aluminum-plastic film and the second aluminum-plastic film; after the sealing, sequentially performing chemical formation, puncturing the air bag, vacuuming, secondary sealing, and cutting the air bag; after the air bag is cut off, the first aluminum-plastic film and the second aluminum-plastic film are connected to each other to form an aluminum-plastic film packaging structure, and the aluminum-plastic film packaging structure includes a main body and a sealing edge portion. A cavity is provided inside the main body, and the battery body of the battery cell is accommodated in the cavity. The edge sealing portion is connected to the outer edge of the main body, the edge sealing portion surrounds the main body, and the edge sealing portion seals the cavity. The outer edge of the edge sealing portion includes a first side edge and a pressure relief area. A portion of the battery cell's tab passes through the first side edge to the outside of the aluminum-plastic film packaging structure, and the two ends of the pressure relief area are respectively connected to the two ends of the first side edge; a glue layer is provided in the pressure relief area so that: a portion of the pressure relief area is covered by the glue layer, and another portion of the pressure relief area is exposed outside the glue layer.

[0018] The method for manufacturing a soft-pack battery according to the second embodiment of the present invention has at least the following beneficial effects: it can manufacture the above-mentioned soft-pack battery with higher safety.

[0019] According to some embodiments of the present invention, the soft-pack battery manufacturing method further includes: after cutting off the air bag and before setting the glue layer, cutting the four corners of the rectangular aluminum-plastic film packaging structure, so that: the pressure relief area includes a first connecting edge, a second side edge, a second connecting edge, a third side edge, a third connecting edge, a fourth side edge and a fourth connecting edge connected in sequence, the third side edge is arranged opposite to the first side edge, the second side edge is arranged opposite to the fourth side edge, the second side edge and the fourth side edge are respectively located on both sides of the first side edge, the end of the first connecting edge away from the second side edge is connected to the first side edge, and the end of the fourth connecting edge away from the fourth side edge is connected to the first side edge; setting the glue layer in the pressure relief area includes: making the glue layer cover the second side edge, the third side edge and the fourth side edge, and leaving at least one of the first connecting edge, the second connecting edge, the third connecting edge and the fourth connecting edge exposed outside the glue layer.

[0020] According to some embodiments of the present invention, the soft-pack battery manufacturing method further includes: after the adhesive layer is set, bending the edge sealing portion so that the edge sealing portion satisfies: the first connecting edge, the second connecting edge, the third connecting edge and the fourth connecting edge are all located on a first plane, at least one of the first side edge, the second side edge, the third side edge and the fourth side edge is located on a second plane, and the first plane and the second plane are parallel to each other.

[0021] According to some embodiments of the present invention, a method for manufacturing a soft-pack battery includes the following steps: preparing a cell assembly; wherein the cell assembly includes a separator, a first cell, a second cell, a first electrolyte and a second electrolyte, the second electrolyte is the same as the first electrolyte, the first aluminum-plastic film and the separator are interconnected to form a closed first space, the first space includes a first crater area and a first air bag area that are interconnected, the first cell and the first electrolyte are located in the first crater area, the first aluminum-plastic film and the second aluminum-plastic film are respectively arranged on different sides of the separator, the second aluminum-plastic film and the separator are interconnected to form a closed second space, the separator is used to prevent the first electrolyte from transferring from the first space to the second space, the separator is also used to prevent the second electrolyte from transferring from the second space to the first space, the second space is separated from the first space, the second space includes a second crater area and a second air bag area that are interconnected, the second cell and the second electrolyte are located in the second crater area, the first air bag area and the The second air bag areas are staggered with each other; the battery cell assembly is subjected to chemical formation; after the chemical formation is completed, the first air bag area is first pierced and the first space is vacuumed; after the vacuuming of the first space is completed, the first crater area is sealed; after the first crater area is sealed, the second air bag area is pierced and the second space is vacuumed; after the vacuuming of the second space is completed, the second crater area is sealed, and then the first air bag area and the second air bag area are cut off; after the second air bag area is cut off, a glue layer is provided in the pressure relief area so that: a part of the pressure relief area is covered by the glue layer, and the other part of the pressure relief area is exposed outside the glue layer; wherein, after the second air bag area is cut off, the first aluminum-plastic film and the second aluminum-plastic film form an aluminum-plastic film packaging structure, the aluminum-plastic film packaging structure includes a sealing edge portion, the outer edge of the sealing edge portion includes a first side edge and a pressure relief area, a part of the pole ear of the first battery cell passes through the first side edge to the outside of the aluminum-plastic film packaging structure, and the two ends of the pressure relief area are respectively connected to the two ends of the first side edge.

[0022] According to some embodiments of the present invention, the battery cell assembly also includes a first isolation glue, which is connected to the side of the partition facing away from the first aluminum-plastic film. The first isolation glue is located at the end of the partition away from the first battery cell, and the melting point of the first isolation glue is higher than the melting point of the heat sealing layer of the first aluminum-plastic film.

[0023] According to some embodiments of the present invention, the battery cell assembly includes a second isolation glue, and the melting point of the second isolation glue is higher than the melting point of the heat sealing layer of the second aluminum-plastic film; wherein, the second isolation glue is provided with one, the second isolation glue is connected to the side of the first aluminum-plastic film facing the partition and is located at the end of the first overlapping part away from the first battery cell; or, the second isolation glue is provided with one, the second isolation glue is connected to the side of the partition facing the first aluminum-plastic film and is located at the end of the second overlapping part away from the first battery cell; or, the second isolation glue is provided with two, the two second isolation glues overlap with each other, one of the second isolation glues is connected to the side of the first aluminum-plastic film facing the partition and is located at the end of the first overlapping part away from the first battery cell, and the other second isolation glue is connected to the side of the partition facing the first aluminum-plastic film and is located at the end of the second overlapping part away from the first battery cell.

[0024] According to some embodiments of the present invention, the battery cell assembly also includes a third isolation glue, the melting point of the third isolation glue is higher than the melting point of the heat-sealing layer of the second aluminum-plastic film, and the second crater area, the third isolation glue and the second isolation glue are arranged in sequence along the third direction; wherein, one third isolation glue is provided, and the third isolation glue is connected to the side of the partition facing the second aluminum-plastic film; or, one third isolation glue is provided, and the third isolation glue is connected to the side of the second aluminum-plastic film facing the partition; or, two third isolation glues are provided, and the two third isolation glues overlap with each other, one of the third isolation glues is connected to the side of the partition facing the second aluminum-plastic film, and the other third isolation glue is connected to the side of the second aluminum-plastic film facing the partition.

[0025] According to some embodiments of the present invention, a method for manufacturing a soft-pack battery includes the following steps: preparing a cell assembly; wherein the cell assembly includes a separator, a first cell, a second cell, a first electrolyte and a second electrolyte, the second electrolyte is the same as the first electrolyte, the first aluminum-plastic film and the separator are interconnected to form a closed first space, the first space includes a first crater area and a first air bag area that are interconnected, the first cell and the first electrolyte are located in the first crater area, the first aluminum-plastic film and the second aluminum-plastic film are respectively arranged on different sides of the separator, the second aluminum-plastic film and the separator are interconnected to form a closed second space, the separator is used to prevent the first electrolyte from transferring from the first space to the second space, the separator is also used to prevent the second electrolyte from transferring from the second space to the first space, the second space is separated from the first space, the second space includes a second crater area and a second air bag area that are interconnected, the second cell and the second electrolyte are located in the second crater area, the first air bag area and the second The air bag areas are staggered with each other; the battery cell assembly is subjected to chemical formation; after the chemical formation is completed, the first air bag area is first pierced and the first space is vacuumed; after the vacuuming of the first space is completed, the first crater area is sealed, and then the first air bag area is cut off; after the first air bag area is cut off, the second air bag area is pierced and the second space is vacuumed; after the vacuuming of the second space is completed, the second crater area is sealed, and then the second air bag area is cut off; after the second air bag area is cut off, a glue layer is provided in the pressure relief area, so that: a part of the pressure relief area is covered by the glue layer, and the other part of the pressure relief area is exposed outside the glue layer; wherein, after the second air bag area is cut off, the first aluminum-plastic film and the second aluminum-plastic film form an aluminum-plastic film packaging structure, the aluminum-plastic film packaging structure includes a sealing edge portion, the outer edge of the sealing edge portion includes a first side edge and a pressure relief area, a part of the pole ear of the first battery cell passes through the first side edge to the outside of the aluminum-plastic film packaging structure, and the two ends of the pressure relief area are respectively connected to the two ends of the first side edge.

[0026] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0028] FIG1 is a schematic diagram of a soft-pack battery according to a first embodiment of the present invention;

[0029] FIG2 is a cross-sectional view of the soft-pack battery of FIG1 along the AA cross section;

[0030] FIG3 is a cross-sectional view of the soft-pack battery of FIG1 along the BB section;

[0031] FIG4 is a cross-sectional view of the soft-pack battery of FIG1 along the CC section;

[0032] FIG5 is a cross-sectional view of a soft-pack battery according to a second embodiment of the present invention;

[0033] FIG6 is an exploded view of a soft-pack battery according to a third embodiment of the present invention;

[0034] FIG7 is a schematic diagram of a method for manufacturing a soft-pack battery according to an embodiment of the present invention;

[0035] FIG8 is a schematic diagram of a battery cell assembly according to an embodiment of the present invention;

[0036] FIG9 is a schematic diagram of a battery cell assembly when the first air bag area is punctured;

[0037] FIG10 is a schematic diagram of a battery cell assembly after the first punching area is sealed;

[0038] FIG11 is a schematic diagram of a battery cell assembly when the second air bag area is punctured;

[0039] FIG12 is a schematic diagram of the battery cell assembly after the second punching area is sealed;

[0040] FIG13 is a schematic diagram of a battery cell assembly with the first air pocket area and the second air pocket area removed;

[0041] FIG14 is an exploded view of the battery cell assembly of FIG8 .

[0042] Reference numerals:

[0043] 100 - soft pack battery, 101 - aluminum-plastic film packaging structure, 102 - main body, 103 - edge sealing portion, 104 - first side, 105 - first connecting edge, 106 - second side, 107 - second connecting edge, 108 - third side, 109 - third connecting edge, 110 - fourth side, 111 - fourth connecting edge, 112 - battery cell, 113 - battery cell body, 114 - tab, 115 - tab glue, 116 - glue layer, 117 - chamfer, 118 - first aluminum-plastic film, 119 - second aluminum-plastic film, 120 - cavity, 121 - first battery cell, 122 - second battery cell, 123 - separator;

[0044] 201-first plane, 202-second plane;

[0045] 301-first space, 302-first flushing area, 303-first air bag area, 304-second space, 305-second flushing area, 306-second air bag area;

[0046] 401-first overlapping portion, 402-first peripheral portion, 403-second overlapping portion, 404-second peripheral portion, 405-first isolation adhesive, 406-second isolation adhesive, 407-third isolation adhesive;

[0047] 501-first straight line, 502-second straight line. DETAILED DESCRIPTION

[0048] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0049] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0050] In the description of the present invention, "several" means more than one, "plurality" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of "first" and "second" in the description is solely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0051] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0052] FIG1 shows a soft-pack battery 100 according to a first embodiment of the present invention, and FIG2 to FIG4 are cross-sectional views of the soft-pack battery 100 according to the first embodiment at different cross-sections. The soft-pack battery 100 includes a battery cell 112, an aluminum-plastic film packaging structure 101, and an adhesive layer 116. As shown in FIG4, the battery cell 112 includes a battery cell body 113 and a tab 114 that are connected to each other. The battery cell 112 can be configured as a laminated battery cell or a wound battery cell. If the battery cell 112 is a laminated battery cell, the battery cell body 113 is formed by stacking a positive electrode sheet, an insulating separator, and a negative electrode sheet; if the battery cell 112 is a wound battery cell, the battery cell body 113 is formed by stacking and winding a positive electrode sheet, an insulating separator, and a negative electrode sheet.

[0053] As shown in Figures 1 and 2, the aluminum-plastic film packaging structure 101 includes a first aluminum-plastic film 118 and a second aluminum-plastic film 119 stacked on top of each other. The central region of the first aluminum-plastic film 118 and the central region of the second aluminum-plastic film 119 are stacked together to form the main body 102. The peripheral regions of the first aluminum-plastic film 118 and the peripheral regions of the second aluminum-plastic film 119 are stacked and connected to each other to form the edge sealing portion 103. In other embodiments, the aluminum-plastic film packaging structure 101 may also include only one sheet of aluminum-plastic film. When the sheet is folded in half, the two halves of the sheet are connected to form the main body 102 and the edge sealing portion 103.

[0054] As shown in Figure 2, a cavity 120 is provided inside the main body 102, and the battery body 113 is accommodated in the cavity 120. The soft-pack battery 100 also includes an electrolyte (not shown), which is also accommodated in the cavity 120, and the electrolyte is in contact with the battery cell 112. As shown in Figure 1, the edge sealing portion 103 is connected to the outer edge of the main body 102, and the edge sealing portion 103 surrounds the main body 102, and the edge sealing portion 103 seals the cavity 120. Sealing the cavity 120 means separating the cavity 120 and the external environment (such as the atmospheric environment) from each other to prevent the electrolyte from leaking into the external environment.

[0055] The portion of the first aluminum-plastic film 118 located at the edge seal portion 103 and the portion of the second aluminum-plastic film 119 located at the edge seal portion 103 are bonded to each other, thereby sealing the cavity 120. The first aluminum-plastic film 118 and the second aluminum-plastic film 119 both include heat-sealing layers, which are not shown and are made of PP (polypropylene). The heat-sealing layer of the first aluminum-plastic film 118 is located on the side of the first aluminum-plastic film 118 facing the second aluminum-plastic film 119, and the heat-sealing layer of the second aluminum-plastic film 119 is located on the side of the second aluminum-plastic film 119 facing the first aluminum-plastic film 118. Pressing the first aluminum-plastic film 118 and the second aluminum-plastic film 119 together and heating them can melt the heat-sealing layers; after stopping heating, the heat-sealing layers solidify, thereby bonding the first aluminum-plastic film 118 and the second aluminum-plastic film 119 to each other.

[0056] As shown in Figure 1, the outer edge of the edge seal 103 includes a first side edge 104 and a pressure relief zone. A portion of the tab 114 extends from the first side edge 104 to the exterior of the aluminum-plastic film packaging structure 101. The pressure relief zone's two ends are respectively connected to the two ends of the first side edge 104. A portion of the pressure relief zone is covered by the adhesive layer 116, while another portion is exposed outside the adhesive layer 116. "Exposed outside the adhesive layer 116" means not covered by the adhesive layer 116. In this embodiment, the pressure relief zone includes a first connecting edge 105, a second side edge 106, a second connecting edge 107, a third side edge 108, a third connecting edge 109, a fourth side edge 110, and a fourth connecting edge 111, which are connected in sequence. One end of the pressure relief zone is the front end of the first connecting edge 105, which is connected to the left end of the first side edge 104. The other end of the pressure relief zone is the front end of the fourth connecting edge 111, which is connected to the right end of the first side edge 104.

[0057] In addition to the heat-sealing layer of the aluminum-plastic film itself, the adhesive layer 116 also has an adhesive effect on the edges of the first aluminum-plastic film 118 and the second aluminum-plastic film 119 . The adhesive layer 116 is beneficial to improving the sealing performance of the aluminum-plastic film packaging structure 101 .

[0058] Compared with the portion of the pressure relief area covered by the adhesive layer 116, the sealing effect of the portion of the pressure relief area not covered by the adhesive layer 116 is weaker. Therefore, when the temperature and pressure inside the cavity 120 are high, the portion of the pressure relief area not covered by the adhesive layer 116 will be first flushed open by the high-temperature gas in the cavity 120, and the sealing of the portion of the pressure relief area not covered by the adhesive layer 116 will fail first, and the high-temperature gas will be discharged outside the cavity 120. As the high-temperature gas is discharged, the pressure inside the cavity 120 decreases, and the risk of explosion of the soft-pack battery 100 is reduced. The soft-pack battery 100 of the present invention constructs a pressure-relieving portion on the outer edge of the aluminum-plastic film packaging structure 101, thereby reducing the risk of explosion of the soft-pack battery 100.

[0059] The following describes the pressure relief areas that need to be covered by the adhesive layer 116 and the areas that need to be exposed outside the adhesive layer 116.

[0060] As shown in Figure 1, the pressure relief area includes a second side 106, a third side 108, and a fourth side 110. The third side 108 is disposed opposite the first side 104, and the second side 106 is disposed opposite the fourth side 110. The second side 106 and the fourth side 110 are respectively located on either side of the first side 104. An adhesive layer 116 covers the second side 106, the third side 108, and the fourth side 110. The first side 104 and the second side 106 may be perpendicular to each other, the second side 106 and the fourth side 110 may be parallel to each other, and the first side 104 and the third side 108 may be parallel to each other. Referring to Figures 2 and 4, the second side 106, the third side 108, and the fourth side 110 are all covered by the adhesive layer 116.

[0061] As shown in Figure 1, the pressure relief zone also includes a first connecting edge 105, a second connecting edge 107, a third connecting edge 109, and a fourth connecting edge 111. The two ends of the first connecting edge 105 are respectively connected to the first side edge 104 and the second side edge 106, and the angle between the first side edge 104 and the second side edge 106 and the first connecting edge 105 is an obtuse angle. The two ends of the second connecting edge 107 are respectively connected to the second side edge 106 and the third side edge 108, and the angle between the second side edge 106 and the third side edge 108 and the second connecting edge 107 is an obtuse angle. The two ends of the third connecting edge 109 are respectively connected to the third side edge 108 and the fourth side edge 110, and the angle between the third side edge 108 and the fourth side edge 110 and the third connecting edge 109 is an obtuse angle. The ends of the fourth connecting edge 111 are connected to the fourth side edge 110 and the first side edge 104, respectively. The angle between the first side edge 104 and the fourth side edge 110 and the fourth connecting edge 111 is an obtuse angle. As shown in Figure 3, the second connecting edge 107 and the third connecting edge 109 are not provided with the adhesive layer 116. Similarly, the second connecting edge 107 and the fourth connecting edge 111 are also not provided with the adhesive layer 116.

[0062] In other embodiments, the pressure relief zone does not necessarily include the first to fourth connecting edges 105 to 111 . The pressure relief zone only needs to include at least one of the first connecting edge 105 , the second connecting edge 107 , the third connecting edge 109 and the fourth connecting edge 111 .

[0063] The advantage of the above-mentioned setting method of the pressure relief zone is that when the area of ​​the pressure relief zone not covered by the adhesive layer 116 is opened by the high-temperature gas, the open part of the aluminum-plastic film packaging structure 101 is mainly located at the corner position of the soft-pack battery 100, and the open part of the aluminum-plastic film packaging structure 101 is smaller after being opened.

[0064] To facilitate processing and improve aesthetics, the angle between the first side 104 and the second side 106 and the second connecting edge 107 is 135°. Similarly, the angle between the second side 106 and the third side 108 and the second connecting edge 107 is 135°; the angle between the third side 108 and the fourth side 110 and the second connecting edge 107 is 135°; and the angle between the fourth side 110 and the first side 104 and the second connecting edge 107 is 135°.

[0065] It should be noted that the first side 104 is not covered by the adhesive layer 116. As shown in FIG3 , the soft-pack battery 100 further includes a tab adhesive 115, which is connected to the tab 114 and is sandwiched between the first aluminum-plastic film 118 and the second aluminum-plastic film 119. The tab adhesive 115 is located at the first side 104. The tab adhesive 115 can enhance the sealing between the aluminum-plastic film packaging structure 101 and the tab 114, reducing the risk of electrolyte leakage from the first side 104. Due to the presence of the tab adhesive 115, the connection between the first aluminum-plastic film 118 and the second aluminum-plastic film 119 at the first side 104 is relatively strong, and the high-temperature gas in the cavity 120 is not easy to break through the first side 104. The high-temperature gas is mainly discharged through the portion of the pressure relief area not covered by the adhesive layer 116. Since the high-temperature gas in the cavity 120 is not easy to break through the first side 104 , the high-temperature gas will not be directly discharged to the vicinity of the tab 114 , which is beneficial to improving the safety of the electrical equipment connected to the tab 114 .

[0066] The adhesive layer 116 can be configured as an insulator. In this way, the adhesive layer 116 can wrap a portion of the edge of the aluminum-plastic film packaging structure 101, reducing the risk of exposing the aluminum layer of the aluminum-plastic film packaging structure 101, thereby reducing the risk of short circuit between the soft-pack battery 100 and external objects.

[0067] The adhesive layer 116 can be configured as a solidified UV-curable adhesive. The main component of the UV-curable adhesive is acrylate. Using UV-curable adhesive as the adhesive layer 116 is beneficial for improving the manufacturing efficiency of the soft-pack battery 100. Specifically, during the manufacturing process of the soft-pack battery 100, the manufacturer can first apply unsolidified UV-curable adhesive to the area of ​​the pressure relief area where the adhesive needs to be applied, and then irradiate the UV-curable adhesive with UV light, thereby accelerating the UV curing process, increasing the molding speed of the adhesive layer 116, and further improving the manufacturing efficiency of the soft-pack battery 100.

[0068] FIG5 shows a soft-pack battery 100 according to a second embodiment of the present invention. In the second embodiment, the edge seal 103 is bent. The bent edge seal 103 satisfies the following requirements: the first connecting edge 105, the second connecting edge 107, the third connecting edge 109, and the fourth connecting edge 111 are all located on the first plane 201, at least one of the first side 104, the second side 106, the third side 108, and the fourth side 110 is located on the second plane 202, and the first plane 201 and the second plane 202 are parallel to each other. The bent edge seal 103 can, on the one hand, reduce the space occupied by the soft-pack battery 100, and on the other hand, increase the resistance of the high-temperature gas in the cavity 120 to the second side 106, the third side 108, and the fourth side 110, thereby causing the high-temperature gas to flow mainly to the connecting edges and be discharged from the connecting edges.

[0069] Figure 6 shows a soft-pack battery 100 according to a third embodiment of the present invention. The battery cell 112 is a laminated cell and has four chamfers 117. These chamfers 117 correspond to the first, second, third, and fourth connecting edges 105, 107, 109, and 111, respectively. The chamfers 117 provide a better fit between the outer edge of the battery cell 112 and the shape of the cavity 120, reducing the gap between the battery cell 112 and the wall of the cavity 120 and improving the energy density of the soft-pack battery 100.

[0070] As shown in Figure 6, the soft-pack battery 100 also includes a separator 123, which is located in the cavity 120. The separator 123 divides the cavity 120 into two sub-chambers. There are two battery cells 112, which are the first battery cell 121 and the second battery cell 122. The two battery cells 112 are respectively arranged in different sub-chambers, with part of the electrolyte located in one of the sub-chambers and the other part of the electrolyte located in the other sub-chamber. The separator 123 is a polymer material (such as plastic) and is used to prevent the electrolyte from passing through. The energy density of the soft-pack battery 100 with two battery cells 112 is higher.

[0071] In the third embodiment, since the soft pack battery 100 also includes a separator 123, the first aluminum-plastic film 118 and the second aluminum-plastic film 119 are not directly bonded. The peripheral area of ​​the first aluminum-plastic film 118 and the peripheral area of ​​the separator 123 are bonded, thereby forming one sub-chamber between the central area of ​​the first aluminum-plastic film 118 and the central area of ​​the separator 123; the peripheral area of ​​the second aluminum-plastic film 119 and the peripheral area of ​​the separator 123 are bonded, thereby forming another sub-chamber between the central area of ​​the second aluminum-plastic film 119 and the central area of ​​the separator 123.

[0072] Next, the manufacturing method of the soft pack battery 100 is introduced. As shown in FIG7 , the manufacturing method of the soft pack battery 100 includes the following steps:

[0073] S10: Manufacturing a battery cell assembly. The manufactured battery cell assembly includes a battery cell 112 and an aluminum-plastic film packaging structure 101 (the battery cell assembly does not include the adhesive layer 116). The specific shapes and structures of the battery cell 112 and the aluminum-plastic film packaging structure 101 are as described above.

[0074] S20 : ​​providing an adhesive layer 116 in the pressure relief area, such that a portion of the pressure relief area is covered by the adhesive layer 116 and another portion of the pressure relief area is exposed outside the adhesive layer 116 .

[0075] In step S20 , the adhesive layer 116 is formed as follows: the manufacturer manually applies glue to a certain portion of the pressure relief area, or an automated device applies glue to a certain portion of the pressure relief area, and after the glue solidifies, the adhesive layer 116 is formed.

[0076] As shown in FIG7 , if the soft pack battery 100 to be manufactured includes only one battery cell 112 , the manufacturing steps of the battery cell assembly (i.e., step S10 ) include:

[0077] S11: placing the battery cell 112 between the first aluminum-plastic film 118 and the second aluminum-plastic film 119, and connecting a portion of the edge of the first aluminum-plastic film 118 to a portion of the edge of the second aluminum-plastic film 119;

[0078] S12: injecting electrolyte into the battery cell 112, and then sealing the first aluminum-plastic film 118 and the second aluminum-plastic film 119;

[0079] S13: After the first seal, the steps are: forming, puncturing the air bag, vacuuming, second sealing, and removing the air bag.

[0080] After removing the airbag, the battery cell assembly is obtained. Step S11 may specifically include connecting the front, left, and rear edges of the first aluminum-plastic film 118 to the front, left, and rear edges of the second aluminum-plastic film 119, respectively; while the right edge of the first aluminum-plastic film 118 and the right edge of the second aluminum-plastic film 119 are not connected, thereby forming an opening. Accordingly, in step S12, electrolyte is injected through the aforementioned opening between the first and second aluminum-plastic films 118, 119, and into the battery cell 112. After the injection is completed, the right edge of the first aluminum-plastic film 118 and the right edge of the second aluminum-plastic film 119 are connected, thus "sealing." The steps of forming, puncturing the airbag, vacuuming, resealing, and removing the airbag in step S13 are all well-known techniques in the art and will not be described in detail here. How to connect the edges of the two aluminum-plastic films has been described above and will not be repeated here.

[0081] As shown in FIG7 , in one embodiment, the manufacturing method of the soft pack battery 100 further includes the following steps:

[0082] S14: After removing the air bag and before setting the adhesive layer 116, the four corners of the rectangular aluminum-plastic film packaging structure 101 are cut so that: the pressure relief area includes a first connecting edge 105, a second side edge 106, a second connecting edge 107, a third side edge 108, a third connecting edge 109, a fourth side edge 110 and a fourth connecting edge 111 connected in sequence.

[0083] Accordingly, in step S20, setting the adhesive layer 116 in the pressure relief area includes the following steps: making the adhesive layer 116 cover the second side 106, the third side 108 and the fourth side 110, and making at least one of the first connecting edge 105, the second connecting edge 107, the third connecting edge 109 and the fourth connecting edge 111 exposed outside the adhesive layer 116.

[0084] As shown in FIG7 , in one embodiment, the manufacturing method of the soft pack battery 100 further includes the following steps:

[0085] S30: After the adhesive layer 116 is set, bend the edge sealing portion 103 so that the edge sealing portion 103 satisfies: the first connecting edge 105, the second connecting edge 107, the third connecting edge 109 and the fourth connecting edge 111 are all located on the first plane 201, at least one of the first side edge 104, the second side edge 106, the third side edge 108 and the fourth side edge 110 is located on the second plane 202, and the first plane 201 and the second plane 202 are parallel to each other.

[0086] This arrangement allows a portion of the edge sealing portion 103 to be bent. The bent edge sealing portion 103 can, on the one hand, reduce the space occupied by the soft-pack battery 100, and on the other hand, increase the resistance of the high-temperature gas in the cavity 120 to flow toward the second side 106, the third side 108 and the fourth side 110, so that the high-temperature gas mainly flows toward the connecting edge and is discharged from the connecting edge.

[0087] The above describes a method for manufacturing a soft-pack battery 100 including only one battery cell 112. The manufacturing method for a soft-pack battery 100 including a separator 123 and two battery cells 112 is slightly different from the method described above. The following describes a method for manufacturing a soft-pack battery 100 including two battery cells 112.

[0088] For a soft-pack battery 100 including two battery cells 112, in one embodiment, a method for manufacturing the soft-pack battery 100 includes:

[0089] S40: A battery cell assembly is produced. As shown in Figure 8, the produced battery cell assembly includes a separator 123, a first battery cell 121, a second battery cell 122, a first electrolyte, and a second electrolyte. The second electrolyte is the same as the first electrolyte. The first aluminum-plastic film 118 and the separator 123 are interconnected to form a sealed first space 301. The first space 301 includes a first crater area 302 and a first air pocket area 303 that are interconnected. The first battery cell 121 and the first electrolyte are located in the first crater area 302. The first aluminum-plastic film 118 and the second aluminum-plastic film 119 are disposed on different sides of the separator 123. The second aluminum-plastic film 119 and the separator 123 are interconnected to form a sealed second space 304. The separator 123 is used to prevent the first electrolyte from migrating from the first space 301 to the second space 304. The separator 123 also prevents the second electrolyte from migrating from the second space 304 to the first space 301. The second space 304 is separated from the first space 301. The second space 304 includes a second cavitation area 305 and a second air pocket area 306 that are interconnected. The second battery cell 122 and the second electrolyte are located in the second cavitation area 305 . The first air pocket area 303 and the second air pocket area 306 are staggered with each other.

[0090] S41: forming the battery cell components;

[0091] S42: After the formation is completed, the first air bag area 303 is pierced (as shown in FIG9 ) and the first space 301 is evacuated;

[0092] S43: After the first space 301 is vacuumed, the first crater area 302 is sealed (as shown in FIG. 10 );

[0093] S44: After sealing the first crater area 302, pierce the second air pocket area 306 (as shown in FIG. 11) and evacuate the second space 304;

[0094] S45: After the vacuuming of the second space 304 is completed, the second crater area 305 is sealed (as shown in FIG12 ), and then the first air pocket area 303 and the second air pocket area 306 are cut out (as shown in FIG13 ). After the second air pocket area 306 is cut out, the first aluminum-plastic film 118 and the second aluminum-plastic film 119 form the aluminum-plastic film packaging structure 101, the specific structure of which is as described above.

[0095] S46 : After the second air pocket area 306 is cut out, a glue layer 116 is provided in the pressure relief area, so that a portion of the pressure relief area is covered by the glue layer 116 and another portion of the pressure relief area is exposed outside the glue layer 116 .

[0096] The risk of explosion of the soft-pack battery 100 produced by the method of this embodiment (steps S40-S46) is low, and the safety of the soft-pack battery 100 is high. In addition, in this embodiment, the first airbag area 303 and the second airbag area 306 are staggered with each other, and when the first airbag area 303 is punctured, the second airbag area 306 can still remain intact (i.e., not punctured). In this way, when the first space 301 is subsequently evacuated, only the electrolyte in the first space 301 will flow out of the aluminum-plastic film packaging structure 101, and the electrolyte in the second space 304 will not flow out. This is conducive to the user to determine the liquid retention coefficient of the first battery cell 121 and the second battery cell 122 respectively. Moreover, since this method cuts out the first airbag area 303 and the second airbag area 306 at the same time, the production efficiency of this method is relatively high.

[0097] The liquid retention coefficient is the ratio of the mass of electrolyte ultimately adsorbed by the battery cell 112 to the mass of electrolyte initially injected into the battery cell 112. The liquid retention coefficient can be detected or determined by measuring the total weight of the battery cell 112 before injection and again after vacuuming. The difference between these two weights is the liquid retention coefficient of the battery cell 112.

[0098] A liquid retention coefficient that does not meet the standard may reduce the safety of the soft-pack battery 100. If the liquid retention coefficient of a certain battery cell 112 is too high, there will be more side reactions when the battery cell 112 reacts with the electrolyte, the battery cell 112 is more likely to produce gas, and the battery is more likely to swell or even explode. The above method allows the two air bags to be staggered, so that it is convenient for the manufacturer to determine the liquid retention coefficient of each battery cell 112, and then it is convenient for the user to determine whether the safety of the battery cell 112 meets the standard, so as to prevent the manufacturer from treating batteries that do not meet the safety standards as qualified products. The above method not only allows the two air bags to be staggered, but also uses the glue layer 116 to construct a part that can release pressure, so that the battery has higher safety.

[0099] For the battery cell assembly manufactured in step S40, the first air-pocket area 303 and the second air-pocket area 306 may be spaced apart in the third direction, and the first air-pocket area 303 and the second air-pocket area 306 may be located on the same side of the first battery cell 121. Alternatively, the first air-pocket area 303 and the second air-pocket area 306 may be spaced apart in the third direction, and the first air-pocket area 303 and the second air-pocket area 306 may be located on different sides of the first battery cell 121. Alternatively, the first air-pocket area 303 and the second air-pocket area 306 may be spaced apart in the second direction, and the first air-pocket area 303 and the second air-pocket area 306 may be located on the same side of the first battery cell 121.

[0100] The first battery cell 121 and the second battery cell 122 are stacked along a first direction. The tab 114 of the first battery cell 121 is located at one end of the first battery cell 121 along the second direction. Any two of the first, second, and third directions are perpendicular to each other. The first direction corresponds to the up-down direction, the second direction corresponds to the front-back direction, and the third direction corresponds to the left-right direction.

[0101] The following describes how to manufacture the battery cell 112 assembly in step S40.

[0102] As shown in Figure 14, the first aluminum-plastic film 118 includes a first overlapping portion 401 and a first peripheral portion 402, which are sequentially connected along the third direction. The portion of the first aluminum-plastic film 118 located to the left of the first straight line 501 is the first overlapping portion 401, and the portion of the first aluminum-plastic film 118 located to the right of the first straight line 501 is the first peripheral portion 402. Both the first overlapping portion 401 and the first peripheral portion 402 are rectangular. The partition 123 includes a second overlapping portion 403 and a second peripheral portion 404, which are sequentially connected along the third direction. The portion of the partition 123 located to the left of the first straight line 501 is the second overlapping portion 403, and the portion of the partition 123 located to the right of the first straight line 501 is the second peripheral portion 404. Both the second overlapping portion 403 and the second peripheral portion 404 are rectangular. The first overlapping portion 401 and the second overlapping portion 403 overlap, and the first peripheral portion 402 and the second peripheral portion 404 overlap. The edge of the first aluminum-plastic film 118 is connected to the edge of the partition 123, thereby forming a first space 301. The portion of the first space 301 located between the first peripheral portion 402 and the second peripheral portion 404 constitutes the first air pocket area 303. The portion of the first space 301 located between the first overlapping portion 401 and the second overlapping portion 403 comprises a first crater area 302 and a transition area. As shown in Figure 14, the transition area is a portion of the first space 301, located between the first crater area 302 and the first air pocket area 303. The second aluminum-plastic film 119 overlaps the second overlapping portion 403, and the edge of the second aluminum-plastic film 119 is connected to the edge of the second overlapping portion 403, thereby forming a second space 304.

[0103] The first crater area 302 and the second crater area 305 will eventually be located on the left side of the second straight line 502, the second air pocket area 306 and the transition area will be located between the second straight line 502 and the first straight line 501, and the first air pocket area 303 will be located on the right side of the first straight line 501.

[0104] As shown in FIG. 14 , the battery cell 112 assembly further includes a first isolation adhesive 405 , a second isolation adhesive 406 and a third isolation adhesive 407 .

[0105] The first isolation adhesive 405 is connected to the side of the partition 123 facing away from the first aluminum-plastic film 118. The edge of the partition 123 facing away from the first battery cell 121 and the edge of the first aluminum-plastic film 118 facing away from the first battery cell 121 are bonded and sealed by the first isolation adhesive 405. The melting point of the first isolation adhesive 405 is higher than the melting point of the heat seal layer of the first aluminum-plastic film 118. The heat seal layer of the first aluminum-plastic film 118 is made of PP (polypropylene). The first isolation adhesive 405 includes one or more of acrylic resin, polycarbonate, polyurethane, and rubber. As shown in the figure, in the first embodiment, the length of the first isolation adhesive 405 in the second direction is equal to the length of the partition 123 in the second direction. The right edge of the first isolation adhesive 405 coincides with the right edge of the partition 123. The length of the first isolation adhesive 405 in the third direction is less than the length of the partition 123.

[0106] As shown in Figure 14, two second isolation adhesives 406 are provided, and the two second isolation adhesives 406 overlap each other. One of the second isolation adhesives 406 is connected to the side of the first aluminum-plastic film 118 facing the partition 123, and is located at the end of the first superposition part 401 away from the first battery cell 121. The other second isolation adhesive 406 is connected to the side of the partition 123 facing the first aluminum-plastic film 118 and is located at the end of the second superposition part 403 away from the first battery cell 121. The melting point of the second isolation adhesive 406 is higher than the melting point of the heat seal layer of the second aluminum-plastic film 119. The heat seal layer of the second aluminum-plastic film 119 is also made of polypropylene. The material of the second isolation adhesive 406 can refer to the material of the first isolation adhesive 405.

[0107] As shown in Figure 14, two third isolation adhesives 407 are provided, and the two third isolation adhesives 407 overlap each other. One third isolation adhesive 407 is connected to the side of the partition 123 facing the second aluminum-plastic film 119, and the other third isolation adhesive 407 is connected to the side of the second aluminum-plastic film 119 facing the partition 123. The second crater area 305, the third isolation adhesive 407, and the second isolation adhesive 406 are sequentially spaced along the third direction. The melting point of the third isolation adhesive 407 is higher than the melting point of the heat seal layer of the second aluminum-plastic film 119. The material of the third isolation adhesive 407 can be similar to that of the first isolation adhesive 405.

[0108] 14 , the user may first heat-seal the left edge, front edge and rear edge of the first aluminum-plastic film 118 with the left edge, front edge and rear edge of the partition 123 respectively.

[0109] Then, the user injects the first electrolyte from the opening formed by the right edge of the first aluminum-plastic film 118 and the right edge of the partition 123; after the first electrolyte is injected, the user heat-seals the portion of the first aluminum-plastic film 118 corresponding to the first isolation glue 405 and the right edge of the partition 123, thereby sealing the opening and forming a sealed first space 301.

[0110] The temperature of the pressing head is greater than the melting point of the heat seal layer, and the melting points of the first isolation adhesive 405, the second isolation adhesive 406, and the third isolation adhesive 407 are all greater than the temperature of the pressing head. Due to the presence of the first isolation adhesive 405, the pressing head does not directly contact the partition 123 when heat-sealing the right edge of the first aluminum-plastic film 118 and the right edge of the partition 123. This helps to reduce the impact of the high temperature of the pressing head on the partition 123 and also helps prevent the partition 123 from contaminating the pressing head.

[0111] In other embodiments, the first isolation glue 405 can also be set to other shapes or sizes. For example, in order to further reduce the risk of direct contact between the pressure head and the second peripheral portion 404 of the partition 123, the shape and size of the first isolation glue 405 and the second peripheral portion 404 of the partition 123 are exactly the same, and the first isolation glue 405 and the second peripheral portion 404 completely overlap. For another example, the first isolation glue 405 can be set to a "]" shape with the opening facing left (the shape is similar to a square bracket), and the left edge of the first isolation glue 405 coincides with the first straight line 501 in the figure; in this way, when the pressure head heat-seals the front and rear edges of the first aluminum-plastic film 118, the pressure head is not easy to directly contact the second peripheral portion 404, and the risk of the partition 123 contaminating the pressure head is low.

[0112] Similarly, the user can first heat-seal the left edge, front edge, and rear edge of the second aluminum-plastic film 119 with the left edge, front edge, and rear edge of the second overlapping portion 403, respectively. Then, the user injects the second electrolyte from the opening formed by the right edge of the second aluminum-plastic film 119 and the separator 123. After the second electrolyte is injected, the user heat-seals the right edge of the second aluminum-plastic film 119 with the right edge of the second overlapping portion 403, thereby forming a sealed second space 304.

[0113] Due to the presence of the second isolation glue 406, when the right edge of the second aluminum-plastic film 119 and the right edge of the second overlapping portion 403 are heat-sealed, the second isolation glue 406 is not melted, and the right edge of the first overlapping portion 401 and the partition 123 are separated by the second isolation glue 406. The second isolation glue 406 will not cause the right edge of the first overlapping portion 401 to adhere. This ensures that the first crater area 302 and the first air pocket area 303 are interconnected, thereby ensuring that the vacuuming of the first space 301 can be carried out smoothly. It should be noted that, in order to save cost, in other embodiments, the two second isolation glues 406 mentioned above can also be only provided with one of them. Relative to only providing one second isolation glue 406, providing two second isolation glues 406 is conducive to further reducing the risk of adhesion between the first aluminum-plastic film 118 and the partition 123.

[0114] After the first space 301 is vacuumed, the first crater area 302 needs to be sealed. At this time, the pressure head presses the battery cell 112 component, and the position of the pressure head overlaps with the position of the third isolation glue 407. Although the first crater area 302 is sealed, due to the presence of the third isolation glue 407, the second overlapping portion 403 and the second aluminum-plastic film 119 are separated by the third isolation glue 407, and the second aluminum-plastic film 119 and the second overlapping portion 403 will not adhere to each other. This ensures that the second air bag area 306 and the second crater area 305 are connected, thereby ensuring that the subsequent vacuuming of the second space 304 can be carried out smoothly. In order to save costs, in other embodiments, only one of the two third isolation glues 407 mentioned above can also be provided. Compared with only providing one third isolation glue 407, providing two third isolation glues 407 is conducive to further reducing the risk of adhesion between the second aluminum-plastic film 119 and the partition 123.

[0115] For a soft pack battery 100 including two battery cells 112, in another embodiment, the first air pocket area 303 may be cut off first. Specifically, in another embodiment, the manufacturing method of the soft pack battery 100 includes:

[0116] S40': is the same as S40 in the previous embodiment and will not be described again here.

[0117] S41 ′: is the same as S41 in the previous embodiment and will not be described again here.

[0118] S42′: is the same as S42 in the previous embodiment and will not be described again here.

[0119] S43': After the first space 301 is vacuumed, the first punching area 302 is sealed, and then the first air pocket area 303 is cut off;

[0120] S44': After cutting off the first air pocket area 303, piercing the second air pocket area 306 and evacuating the second space 304;

[0121] S45': After the vacuuming of the second space 304 is completed, the second dent area 305 is sealed, and then the second air pocket area 306 is cut out. After the second air pocket area 306 is cut out, the first aluminum-plastic film 118 and the second aluminum-plastic film 119 form the aluminum-plastic film packaging structure 101. The specific structure of the aluminum-plastic film packaging structure 101 is as described above.

[0122] S46′: is the same as S46 in the previous embodiment and will not be described again here.

[0123] The soft-pack battery 100 produced by the method of this embodiment (steps S40'-S46') has a low risk of explosion and a high safety of the soft-pack battery 100. In addition, the method of this embodiment also punctures the first air pocket area 303 and the second air pocket area 306 in sequence, and evacuates the first space 301 and the second space 304 in sequence. The method of this embodiment does not puncture the two air pocket areas at the same time, nor does it evacuate the first space 301 and the second space 304 at the same time, which helps the user determine the liquid retention coefficient of the first battery cell 121 and the liquid retention coefficient of the second battery cell 122.

[0124] In the description of the present invention, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the exemplary expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Claims

1. Soft-pack battery, characterized in that, It includes a battery cell, an aluminum-plastic film packaging structure and an adhesive layer. The battery cell includes a battery cell body and a tab that are connected to each other. The aluminum-plastic film packaging structure includes: A main body portion. A cavity is provided inside the main body portion, and the battery cell body is accommodated in the cavity. A sealing edge portion. The sealing edge portion is connected to the outer edge of the main body portion. The sealing edge portion surrounds the main body portion for one week, and the sealing edge portion seals the cavity. The outer edge of the sealing edge portion includes a first side edge and a pressure relief area. A part of the tab passes out of the aluminum-plastic film packaging structure from the first side edge. Both ends of the pressure relief area are respectively connected to both ends of the first side edge. A part of the pressure relief area is covered by the adhesive layer, and another part of the pressure relief area is exposed outside the adhesive layer.

2. The soft-pack battery according to claim 1, characterized in that, The pressure relief area includes a second side edge, a third side edge and a fourth side edge. The third side edge is disposed opposite to the first side edge. The second side edge is disposed opposite to the fourth side edge. The second side edge and the fourth side edge are respectively located on both sides of the first side edge. The adhesive layer covers the second side edge, the third side edge and the fourth side edge. The pressure relief area further includes: A first connecting edge. Both ends of the first connecting edge are respectively connected to the first side edge and the second side edge. The included angle between any one of the first side edge and the second side edge and the first connecting edge is an obtuse angle. The first connecting edge is exposed outside the adhesive layer. And / or, a second connecting edge. Both ends of the second connecting edge are respectively connected to the second side edge and the third side edge. The included angle between any one of the second side edge and the third side edge and the second connecting edge is an obtuse angle. The second connecting edge is exposed outside the adhesive layer. And / or, a third connecting edge. Both ends of the third connecting edge are respectively connected to the third side edge and the fourth side edge. The included angle between any one of the third side edge and the fourth side edge and the third connecting edge is an obtuse angle. The third connecting edge is exposed outside the adhesive layer. And / or, a fourth connecting edge. Both ends of the fourth connecting edge are respectively connected to the fourth side edge and the first side edge. The included angle between any one of the first side edge and the fourth side edge and the fourth connecting edge is an obtuse angle. The fourth connecting edge is exposed outside the adhesive layer.

3. The soft-pack battery according to claim 2, wherein The pressure relief area includes the first connecting edge, the second connecting edge, the third connecting edge and the fourth connecting edge. The sealing edge portion is bent. The bent sealing edge portion satisfies that the first connecting edge, the second connecting edge, the third connecting edge and the fourth connecting edge are all located on a first plane. At least one of the first side edge, the second side edge, the third side edge and the fourth side edge is located on a second plane. The first plane and the second plane are parallel to each other.

4. The soft-pack battery according to claim 2, wherein The pressure relief area includes a first connecting edge. The included angle between any one of the first side edge and the second side edge and the second connecting edge is 135°. And / or, the pressure relief area includes a second connecting edge. The included angle between any one of the second side edge and the third side edge and the second connecting edge is 135°. And / or, the pressure relief area includes a third connecting edge, and the included angle between any one of the third side and the fourth side and the second connecting edge is 135°; And / or, the pressure relief area includes a fourth connecting edge, and the included angle between any one of the fourth side and the first side and the second connecting edge is 135°.

5. The soft-pack battery according to claim 2, characterized in that, The battery cell is a laminated battery cell, the battery cell includes the first connecting edge, the second connecting edge, the third connecting edge and the fourth connecting edge, the battery cell is provided with four chamfers, and the four chamfers are respectively arranged corresponding to the first connecting edge, the second connecting edge, the third connecting edge and the fourth connecting edge.

6. The soft-pack battery according to claim 1, wherein, The adhesive layer is an insulator.

7. The soft-pack battery according to claim 1, characterized in that, The adhesive layer is a solidified ultraviolet curable adhesive.

8. The soft-pack battery according to claim 1, characterized in that, The soft-pack battery further includes a separator and an electrolyte. The separator is located in the cavity. The separator divides the cavity into two sub-chambers. Two battery cells are provided, and the two battery cells are respectively arranged in different sub-chambers. A part of the electrolyte is located in one of the sub-chambers, and the other part of the electrolyte is located in the other sub-chamber. The separator is used to prevent the electrolyte from passing through.

9. The soft-pack battery according to claim 1, wherein The aluminum-plastic film packaging structure is formed by connecting a first aluminum-plastic film and a second aluminum-plastic film. The central regions of the first aluminum-plastic film and the second aluminum-plastic film are stacked to form the main body part. The peripheral regions of the first aluminum-plastic film and the second aluminum-plastic film are stacked and connected to each other to form a sealing edge part; The soft-pack battery further includes an ear glue, the ear glue is connected to the ear, the ear glue is sandwiched between the first aluminum-plastic film and the second aluminum-plastic film, and the ear glue is arranged at the first side.

10. A method for manufacturing a soft-pack battery, characterized in that, Including the following steps: Place the battery cell between the first aluminum-plastic film and the second aluminum-plastic film, and connect a part of the edge of the first aluminum-plastic film and a part of the edge of the second aluminum-plastic film; Inject electrolyte into the battery cell, and then perform a first sealing on the first aluminum-plastic film and the second aluminum-plastic film; After the first sealing, formation, puncturing the air bag, vacuum pumping, second sealing and cutting off the air bag are carried out in sequence; after the air bag is cut off, the first aluminum-plastic film and the second aluminum-plastic film are connected to each other to form an aluminum-plastic film packaging structure. The aluminum-plastic film packaging structure includes a main body part and a sealing edge part. A cavity is provided inside the main body part. The main body of the battery cell is accommodated in the cavity. The sealing edge part is connected to the outer edge of the main body part. The sealing edge part surrounds the main body part for one week, and the sealing edge part seals the cavity. The outer edge of the sealing edge part includes a first side and a pressure relief area. A part of the ear of the battery cell passes through the first side to the outside of the aluminum-plastic film packaging structure. The two ends of the pressure relief area are respectively connected to the two ends of the first side; Arrange an adhesive layer in the pressure relief area so that: a part of the pressure relief area is covered by the adhesive layer, and the other part of the pressure relief area is exposed outside the adhesive layer.

11. The manufacturing method of the pouch battery according to claim 10, characterized in that, The method for manufacturing the soft-pack battery further includes: After cutting off the airbag and before setting the adhesive layer, cut the four corners of the rectangular aluminum-plastic film packaging structure so that: the pressure relief area includes a first connecting edge, a second side edge, a second connecting edge, a third side edge, a third connecting edge, a fourth side edge, and a fourth connecting edge connected in sequence, the third side edge is disposed opposite to the first side edge, the second side edge is disposed opposite to the fourth side edge, the second side edge and the fourth side edge are respectively located on both sides of the first side edge, one end of the first connecting edge away from the second side edge is connected to the first side edge, and one end of the fourth connecting edge away from the fourth side edge is connected to the first side edge; Setting the adhesive layer in the pressure relief area includes: covering the second side edge, the third side edge, and the fourth side edge with the adhesive layer, and exposing at least one of the first connecting edge, the second connecting edge, the third connecting edge, and the fourth connecting edge outside the adhesive layer.

12. The method for manufacturing a pouch cell according to claim 11, wherein The method for manufacturing the soft-pack battery further includes: After the adhesive layer is set, bend the sealing edge portion so that the sealing edge portion satisfies: the first connecting edge, the second connecting edge, the third connecting edge, and the fourth connecting edge are all located on a first plane, and at least one of the first side edge, the second side edge, the third side edge, and the fourth side edge is located on a second plane, and the first plane and the second plane are parallel to each other.

13. A method for manufacturing a soft-pack battery, characterized in that, Including the following steps: Manufacture a battery cell assembly; wherein, the battery cell assembly includes a separator, a first battery cell, a second battery cell, a first electrolyte, and a second electrolyte, the second electrolyte is the same as the first electrolyte, the first aluminum-plastic film is connected to the separator to form a sealed first space, the first space includes a first pit area and a first airbag area that communicate with each other, the first battery cell and the first electrolyte are located in the first pit area, the first aluminum-plastic film and the second aluminum-plastic film are respectively disposed on different sides of the separator, the second aluminum-plastic film is connected to the separator to form a sealed second space, the separator is used to prevent the first electrolyte from transferring from the first space to the second space, the separator is also used to prevent the second electrolyte from transferring from the second space to the first space, the second space is separated from the first space, the second space includes a second pit area and a second airbag area that communicate with each other, the second battery cell and the second electrolyte are located in the second pit area, and the first airbag area and the second airbag area are offset from each other; Perform formation on the battery cell assembly; After the formation is completed, first pierce the first airbag area and evacuate the first space; After the evacuation of the first space is completed, seal the first pit area; After sealing the first pit area, pierce the second airbag area and evacuate the second space; After the evacuation of the second space is completed, seal the second pit area, and then cut off the first airbag area and the second airbag area; After the second airbag area is cut off, an adhesive layer is provided in the pressure relief area, such that: a part of the pressure relief area is covered by the adhesive layer, and another part of the pressure relief area is exposed outside the adhesive layer; Wherein, after the second airbag area is cut off, the first aluminum-plastic film and the second aluminum-plastic film form an aluminum-plastic film packaging structure. The aluminum-plastic film packaging structure includes a sealing edge portion. The outer edge of the sealing edge portion includes a first side edge and a pressure relief area. A part of the tab of the first battery cell passes through the first side edge to the outside of the aluminum-plastic film packaging structure. Two ends of the pressure relief area are respectively connected to two ends of the first side edge.

14. The cell assembly according to claim 13, wherein The battery cell assembly further includes a first isolation adhesive. The first isolation adhesive is connected to a side of the separator facing away from the first aluminum-plastic film. The first isolation adhesive is located at an end of the separator away from the first battery cell. The melting point of the first isolation adhesive is higher than the melting point of the heat-sealing layer of the first aluminum-plastic film.

15. The cell assembly according to claim 13, characterized in that, The battery cell assembly includes a second isolation adhesive. The melting point of the second isolation adhesive is higher than the melting point of the heat-sealing layer of the second aluminum-plastic film; Wherein, there is one second isolation adhesive. The second isolation adhesive is connected to a side of the first aluminum-plastic film facing the separator and is located at an end of the first overlapping portion away from the first battery cell; Or, there is one second isolation adhesive. The second isolation adhesive is connected to a side of the separator facing the first aluminum-plastic film and is located at an end of the second overlapping portion away from the first battery cell; Or, there are two second isolation adhesives. The two second isolation adhesives overlap each other. One of the second isolation adhesives is connected to a side of the first aluminum-plastic film facing the separator and is located at an end of the first overlapping portion away from the first battery cell. The other second isolation adhesive is connected to a side of the separator facing the first aluminum-plastic film and is located at an end of the second overlapping portion away from the first battery cell.

16. The cell assembly according to claim 15, characterized in that, The battery cell assembly further includes a third isolation adhesive. The melting point of the third isolation adhesive is higher than the melting point of the heat-sealing layer of the second aluminum-plastic film. The second punching area, the third isolation adhesive, and the second isolation adhesive are sequentially arranged at intervals along the third direction; Wherein, there is one third isolation adhesive. The third isolation adhesive is connected to a side of the separator facing the second aluminum-plastic film; Or, there is one third isolation adhesive. The third isolation adhesive is connected to a side of the second aluminum-plastic film facing the separator; Or, there are two third isolation adhesives. The two third isolation adhesives overlap each other. One of the third isolation adhesives is connected to a side of the separator facing the second aluminum-plastic film. The other third isolation adhesive is connected to a side of the second aluminum-plastic film facing the separator.

17. A method for manufacturing a soft-pack battery, characterized in that, Comprising the following steps: A battery cell assembly is obtained; wherein, the battery cell assembly includes a separator, a first battery cell, a second battery cell, a first electrolyte, and a second electrolyte, the second electrolyte is the same as the first electrolyte, the first aluminum plastic film is connected to the separator to form a sealed first space, the first space includes a first pit area and a first airbag area that communicate with each other, the first battery cell and the first electrolyte are located in the first pit area, the first aluminum plastic film and the second aluminum plastic film are respectively arranged on different sides of the separator, the second aluminum plastic film is connected to the separator to form a sealed second space, the separator is used to prevent the first electrolyte from transferring from the first space to the second space, the separator is also used to prevent the second electrolyte from transferring from the second space to the first space, the second space is separated from the first space, the second space includes a second pit area and a second airbag area that communicate with each other, the second battery cell and the second electrolyte are located in the second pit area, and the first airbag area and the second airbag area are offset from each other; The battery cell assembly is formed; After the formation is completed, first pierce the first airbag area and evacuate the first space; After the evacuation of the first space is completed, seal the first pit area, and then cut off the first airbag area; After cutting off the first airbag area, pierce the second airbag area and evacuate the second space; After the evacuation of the second space is completed, seal the second pit area, and then cut off the second airbag area; After the second airbag area is cut off, a glue layer is provided in the pressure relief area, so that: a part of the pressure relief area is covered by the glue layer, and another part of the pressure relief area is exposed outside the glue layer; Wherein, after the second airbag area is cut off, the first aluminum plastic film and the second aluminum plastic film form an aluminum plastic film packaging structure, the aluminum plastic film packaging structure includes a sealing edge part, the outer edge of the sealing edge part includes a first side edge and a pressure relief area, a part of the tab of the first battery cell passes through the first side edge to the outside of the aluminum plastic film packaging structure, and both ends of the pressure relief area are connected to both ends of the first side edge.

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