Packaging structure for soft package battery

Abstract

The utility model discloses a packaging structure for a soft package battery, which comprises an aluminum-plastic film main body, the aluminum-plastic film main body is provided with a first central axis extending along the width direction of the aluminum-plastic film main body, the aluminum-plastic film main body is provided with a battery cell accommodating cavity and an air bag cavity, the battery cell accommodating cavity comprises a first battery cell accommodating cavity and a second battery cell accommodating cavity, the first battery cell accommodating cavity and the second battery cell accommodating cavity are in mirror symmetry relative to a first central axis, the air bag cavities comprise a first air bag cavity and a second air bag cavity, and the first air bag cavity and the second air bag cavity are located on the two sides of the first central axis respectively; and the aluminum plastic film main body is folded along the first central axis, so that the first air bag cavity and the second air bag cavity are crossed. The packaging structure for the soft package battery can avoid air bag adhesion, improve the electrolyte filling efficiency and reduce the defective product rate of liquid injection failure caused by incapability of opening due to air bag adhesion.

Description

Technical Field

[0001] The utility model belongs to the technical field of soft-pack battery packaging, and in particular relates to a packaging structure for soft-pack batteries. Background Art

[0002] Soft-pack batteries refer to lithium-ion batteries that use aluminum-plastic film as packaging material. The core packaging material of soft-pack batteries is aluminum-plastic film, which is a multi-layer composite film with a common structure of PA / / Al / / CPP, where PA is the nylon layer, which is mainly used to protect the Al foil and improve scratch resistance and bending resistance; Al is the aluminum foil, which is mainly used as a molding layer and support layer, and uses the softness and deformation of the aluminum foil to give it various adaptive shapes; CPP is a cast polypropylene layer, which, in addition to isolating the electrolyte of the battery system, also uses its heat-sealing properties to achieve the sealing function of the packaging material and provide insulation performance.

[0003] The packaging of soft-pack batteries usually includes top sealing and side sealing. The two layers of CPP are sealed at a certain temperature and pressure. The heat is transferred from the PA layer to the Al layer and finally reaches the CPP layer. In order to achieve a good sealing effect and prevent the electrolyte from leaking out, the industry generally uses higher temperatures and longer times for packaging. The industry usually only designs the battery shell body, and the airbag area is not specially designed. When the two battery shell bodies are folded in half, the two layers of CPP in the airbag area are usually attached together. The aluminum-plastic film is used as a whole. When the heat is transferred to the area outside the sealing area, the CPP points in the airbag area that were originally in contact will be adhered due to the fusion of CPP. The electrolyte of the lithium-ion battery is filled through one side of the airbag bag. Due to the adhesion of the airbag bag due to heat radiation, the vacuum suction cup cannot fully open the airbag bag, reducing the space of the injection channel, resulting in low filling efficiency, or even inability to fill the electrolyte, and ultimately forming defective products.

[0004] Therefore, there is an urgent need for a packaging structure for soft-pack batteries to solve the deficiencies of the existing technical problems. Utility Model Content

[0005] The utility model aims to provide a packaging structure for a soft-pack battery, which can avoid airbag adhesion, improve electrolyte filling efficiency and reduce the defective product rate caused by injection failure due to airbag adhesion and inability to open.

[0006] To achieve the above purpose, the utility model provides a packaging structure for a soft-pack battery, including an aluminum-plastic film body, the aluminum-plastic film body having a first central axis extending along the width direction of the aluminum-plastic film body, a battery cell accommodating cavity and an air bag cavity are provided on the aluminum-plastic film body, the battery cell accommodating cavity includes a first battery cell accommodating cavity and a second battery cell accommodating cavity, the first battery cell accommodating cavity and the second battery cell accommodating cavity are mirror-symmetrical relative to the first central axis, the air bag cavity includes a first air bag cavity and a second air bag cavity, the first air bag cavity and the second air bag cavity are respectively located on both sides of the first central axis, and the aluminum-plastic film body is folded along the first central axis so that the first air bag cavity and the second air bag cavity are in a cross shape.

[0007] Compared with the prior art, the aluminum-plastic film body of the packaging structure for soft-pack batteries of the utility model is provided with a first airbag cavity and a second airbag cavity, and the first airbag cavity and the second airbag cavity are respectively located on both sides of the first central axis. The partition effect of the first airbag cavity and the second airbag cavity can block the heat transfer from the sealing head in the sealing area, thereby avoiding the adhesion of the airbag during aluminum-plastic film packaging; at the same time, the aluminum-plastic film body is folded along the first central axis to make the first airbag cavity and the second airbag cavity cross-shaped, so that the two layers of CPP of the first airbag cavity and the second airbag cavity will not be completely attached together after folding, which can further reduce the adhesion of the airbag during aluminum-plastic film packaging. Therefore, the packaging structure for soft-pack batteries of the utility model can avoid the adhesion of the airbag during packaging, improve the electrolyte filling efficiency, and reduce the defective rate of liquid injection failure due to the inability to open the airbag due to airbag adhesion.

[0008] Furthermore, the second airbag cavity of the utility model is parallel to the first central axis.

[0009] Furthermore, the aluminum-plastic film body of the utility model has a second central axis extending along the length direction of the aluminum-plastic film body, and the first airbag cavity is parallel to the second central axis.

[0010] Furthermore, the aluminum-plastic film body of the utility model has a second central axis extending along the length direction of the aluminum-plastic film body, and the airbag cavity also includes a third airbag cavity. The third airbag cavity and the first airbag cavity are located on the same side of the first central axis, and the third airbag cavity and the first airbag cavity are mirror-symmetrical relative to the second central axis.

[0011] Furthermore, the first airbag cavity of the utility model is a rectangular body structure, and the second airbag cavity is an inclined body structure. The inclined surface structure can further prevent the airbag bag from sticking, and at the same time, the inclined surface structure allows the electrolyte to enter the battery core more smoothly after being injected.

[0012] Furthermore, the first airbag cavity of the utility model is a rectangular parallelepiped; the second airbag cavity is a trapezoidal prism.

[0013] Furthermore, the second airbag cavity of the utility model is a right-angled trapezoidal prism, and the end surface of the second airbag cavity away from the aluminum-plastic film body is a rectangle.

[0014] Furthermore, the first airbag cavity of the utility model includes a first end face and a first side face connecting the first end face and the aluminum-plastic film body, and the second airbag cavity includes a second end face and a second side face connecting the second end face and the aluminum-plastic film body, and the connection between the first end face and the first side face and the connection between the second end face and the second side face are both chamfered. More specifically, the first end face of the utility model is provided with first side faces on four sides, and the connection between two adjacent first side faces is a chamfered structure; the second end face is provided with second side faces on four sides, and the connection between two adjacent second side faces is a chamfered structure.

[0015] Furthermore, the aluminum-plastic film body of the utility model is folded along the first central axis so that the first battery cell accommodating cavity and the second battery cell accommodating cavity are combined to form a battery cell accommodating cavity, and the shape of the battery cell accommodating cavity matches the shape of the battery cell for packaging.

[0016] Furthermore, the battery cell accommodating cavity of the present invention has a cylindrical structure.

[0017] Furthermore, the utility model includes punching depressions on the aluminum-plastic film body to form a battery cell accommodating cavity and an airbag cavity. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the packaging structure for a soft-pack battery according to the first embodiment of the utility model.

[0019] Figure 2 It is a structural schematic diagram of a packaging structure for a soft-pack battery according to a second embodiment of the present utility model.

[0020] Figure 3 It is a projection diagram of the soft-pack battery packaging structure of the soft-pack cylindrical lithium-ion battery 13450 of the utility model in a direction perpendicular to the plane of the aluminum-plastic film body. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the utility model will be described clearly and completely below in conjunction with the drawings of the specification. It is obvious that the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments.

[0022] It should be noted that the width direction of the aluminum-plastic film body 11 is Figure 1 As indicated by X in 2, the length direction of the aluminum-plastic film body 11 is Figure 1-2 The first central axis is Figure 1-2 The AA line shown in the figure, the second central axis is Figure 1-2 The BB line shown in .

[0023] Please see Figure 1 The packaging structure 100 for a soft-pack battery provided by the utility model includes an aluminum-plastic film body 11, and the aluminum-plastic film body 11 has a first central axis extending along the width direction of the aluminum-plastic film body 11, that is, Figure 1 AA line in, a battery cell accommodating cavity and an airbag cavity are provided on the aluminum-plastic film body 11, the battery cell accommodating cavity includes a first battery cell accommodating cavity 121 and a second battery cell accommodating cavity 122, the first battery cell accommodating cavity 121 and the second battery cell accommodating cavity 122 are mirror-symmetrical relative to the first central axis line AA, the airbag cavity includes a first airbag cavity 131 and a second airbag cavity 132, the first airbag cavity 131 and the second airbag cavity 132 are respectively located on both sides of the first central axis, and the aluminum-plastic film body 11 is folded along the first central axis line AA so that the first airbag cavity 131 and the second airbag cavity 132 are in a cross shape. The partition effect of the first airbag cavity 131 and the second airbag cavity 132 can block the heat transfer from the sealing area head, thereby avoiding the adhesion of the airbag during aluminum-plastic film packaging; at the same time, the aluminum-plastic film body 11 is folded along the first central axis AA line to make the first airbag cavity 131 and the second airbag cavity 132 cross-shaped, so that the two layers of CPP of the first airbag cavity 131 and the second airbag cavity 132 will not be completely attached together after folding, which can further avoid the adhesion of the airbag during aluminum-plastic film packaging. Therefore, the packaging structure 100 for soft-pack batteries of the utility model can avoid the adhesion of airbag bags, improve the electrolyte filling efficiency, and reduce the defective rate of injection failure due to the inability to open the airbag due to adhesion.

[0024] Please continue to see Figure 1 The second airbag cavity 132 of the utility model is parallel to the first central axis AA. Furthermore, the aluminum-plastic film body 11 has a second central axis extending along the length direction of the aluminum-plastic film body 11, that is, Figure 2 The BB line in the figure, the first airbag cavity 131 is parallel to the second central axis BB line, this arrangement is conducive to forming the first airbag cavity 131 and the second airbag cavity 132, and can effectively block the heat transfer from the sealing area head, thereby reducing the adhesion of the aluminum-plastic film packaged airbag.

[0025] Please see Figure 2The aluminum-plastic film body 11 of the utility model has a second central axis line BB extending along the length direction of the aluminum-plastic film body 11, and the airbag cavity also includes a third airbag cavity 133. The third airbag cavity 133 and the first airbag cavity 131 are located on the same side of the first central axis line AA, and the third airbag cavity 133 and the first airbag cavity 131 are mirror-symmetrical relative to the second central axis line BB. The third airbag cavity 133 can obtain a larger airbag space, further play a role in blocking heat transfer, and can accommodate more gas when excessive gas is generated by formation.

[0026] Please continue to see Figure 1-2 The first airbag cavity 131 of the utility model is a rectangular body structure, and the second airbag cavity 132 is an inclined surface structure. The inclined surface structure can further reduce the adhesion of the airbag, and at the same time, the inclined surface structure allows the electrolyte to enter the battery cell more smoothly after injection. Specifically, the first airbag cavity 131 can be a rectangular parallelepiped, and the second airbag cavity 132 can be a trapezoidal prism, such as Figure 1-2 The right-angled trapezoidal prism shown in the figure may of course also be an isosceles trapezoidal prism.

[0027] The first airbag cavity 131 includes a first end surface 1311 and a first side surface portion ( Figure 1-2 (not shown in the figure), the second airbag cavity 132 includes a second end face 1321 and a second side face 1322 connecting the second end face 1321 and the aluminum-plastic film body. In order to keep the surface of the packaging structure 100 for soft-pack batteries smooth, the connection between the first end face 1311 and the first side face and the connection between the second end face 1321 and the second side face 1322 are both chamfered. The first end face 1311 is provided with a first side face on all four sides, and the connection between two adjacent first side faces is a chamfered structure; the second end face 1321 is provided with a second side face 1322 on all four sides, and the connection between two adjacent second side faces 1322 is a chamfered structure.

[0028] In an embodiment of the utility model, the packaging structure 100 for soft-pack batteries can be realized by a stretching mold, and the aluminum-plastic composite film is placed in a designed mold. The mold is pressed downward to punch the aluminum-plastic composite film into a stretched packaging structure 100 for soft-pack batteries of this utility model, and the battery cell is placed in the first battery cell accommodating cavity 121. The aluminum-plastic film body 11 is folded along the first central axis AA line, so that the first battery cell accommodating cavity 121 and the second battery cell accommodating cavity 122 are combined to form a battery cell accommodating cavity. The shape of the battery cell accommodating cavity matches the shape of the battery cell used for packaging. For example, when the battery cell is a cylindrical battery, the battery cell accommodating cavity is cylindrical, that is, the first battery cell accommodating cavity 121 and the second battery cell accommodating cavity 122 are respectively completely symmetrical semi-cylindrical.

[0029] More specifically, see Figure 3, taking the soft-pack cylindrical lithium-ion battery 13450 as an example, the packaging structure 100 for the soft-pack battery of the utility model is described in more detail. The length a of the aluminum-plastic film body 11 is 138 mm, the width b is 55 mm, the distance d between the first battery cell accommodating cavity 121 and the first airbag cavity 131 is 15 mm, the distance e between the second battery cell accommodating cavity 122 and the second airbag cavity 132 is 15 mm, the distance f between the first airbag cavity 131 and the wide side of the aluminum-plastic film body 11 close to the first airbag cavity 131 is 10 mm, and the distance g between the second airbag cavity 132 and the wide side of the aluminum-plastic film body 11 close to the second airbag cavity 132 is 10 mm. Further, the first airbag cavity 131 and the third airbag cavity 133 are completely symmetrical rectangular structures, the second airbag cavity 132 is a right-angled trapezoidal prism, the projection of the first airbag cavity 131 in the direction perpendicular to the plane of the aluminum-plastic film body 11 is a rectangle, the length of the rectangle is 30 mm, the width is 8 mm, the chamfer at the connection between the first end face 1311 and the first side surface is 1.5 mm, the chamfer at the connection between the two adjacent first side surfaces is 2.0 mm, the distance h between the first airbag cavity 131 and the third airbag cavity 133 is 23 mm, the distance j between the first airbag cavity 131 and the long side of the aluminum-plastic film body 11 close to the first airbag cavity 131 is 8 mm, and the distance k between the third airbag cavity 133 and the long side of the aluminum-plastic film body 11 close to the third airbag cavity 133 is 8 mm. Further, the projection of the second airbag cavity 132 in the direction perpendicular to the plane of the aluminum-plastic film body 11 is a rectangle and a trapezoid, wherein the length of the rectangle is 9 mm, the width is 15 mm, the bottom of the trapezoid is 43 mm, the height of the trapezoid is 15 mm, and the distances between the second airbag cavity 132 and the two long sides of the aluminum-plastic film body 11 close to the first airbag cavity 131 are respectively the first distance u and the second distance v, and both u and v are 8 mm, the chamfer at the connection between the second end face 1321 and the second side face 1322 is 1.2 mm, and the chamfer at the connection between the adjacent second side face 1322 is 1.8 mm. More specifically, the mold core corresponding to the first battery cell accommodating cavity 121 and the second battery cell accommodating cavity 122 is composed of a 304 stainless steel base and a PEEK molding die head, the mold core height is 52 mm, and the PEEK molding die head height is 10 mm, so that the shape of the battery cell accommodating cavity obtained matches the shape of the battery cell of the soft-pack cylindrical lithium-ion battery 13450. The mold core corresponding to the second airbag cavity 132 is also composed of a 304 stainless steel base and a PEEK molding die head. The mold core height is 48 mm, and the PEEK molding die head height is 10 mm. That is, during the punching process, the punching depth of the first battery cell accommodating cavity 121 and the second battery cell accommodating cavity 122 is 4 mm higher than the punching depth of the second airbag cavity 132.

[0030] The above disclosure is only the preferred embodiment of the present invention, which certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the scope of the patent application of the present invention are still within the scope covered by the present invention.

Claims

1. A packaging structure for a soft pack battery, characterized in that: It includes an aluminum-plastic film body, which has a first central axis extending along the width direction of the aluminum-plastic film body. The aluminum-plastic film body is provided with a battery cell accommodating cavity and an air bag cavity, the battery cell accommodating cavity includes a first battery cell accommodating cavity and a second battery cell accommodating cavity, the first battery cell accommodating cavity and the second battery cell accommodating cavity are mirror-symmetrical relative to the first central axis, the air bag cavity includes a first air bag cavity and a second air bag cavity, the first air bag cavity and the second air bag cavity are respectively located on both sides of the first central axis, and the aluminum-plastic film body is folded along the first central axis so that the first air bag cavity and the second air bag cavity are in a cross shape.

2. The packaging structure for a soft pack battery according to claim 1, characterized in that: The second airbag cavity is parallel to the first central axis.

3. The packaging structure for a soft pack battery according to claim 2, characterized in that: The aluminum-plastic film body has a second central axis extending along the length direction of the aluminum-plastic film body, and the first airbag cavity is parallel to the second central axis.

4. The packaging structure for a soft pack battery according to claim 2, characterized in that: The aluminum-plastic film body has a second central axis extending along the length direction of the aluminum-plastic film body, and the airbag cavity also includes a third airbag cavity. The third airbag cavity and the first airbag cavity are located on the same side of the first central axis, and the third airbag cavity and the first airbag cavity are mirror-symmetrical relative to the second central axis.

5. The packaging structure for a soft pack battery according to claim 1, characterized in that: The first airbag cavity is a rectangular structure, and the second airbag cavity is an inclined structure.

6. The packaging structure for a soft pack battery according to claim 5, characterized in that: The first airbag cavity is a rectangular parallelepiped; the second airbag cavity is a trapezoidal prism.

7. The packaging structure for a soft pack battery according to claim 6, characterized in that: The second airbag cavity is a right-angled trapezoidal prism, and the end surface of the second airbag cavity away from the aluminum-plastic film body is a rectangle.

8. The packaging structure for a soft pack battery according to claim 5, characterized in that: The first airbag cavity includes a first end face and a first side surface connecting the first end face and the aluminum-plastic film body, the second airbag cavity includes a second end face and a second side surface connecting the second end face and the aluminum-plastic film body, and the connection between the first end face and the first side surface and the connection between the second end face and the second side surface are both chamfered structures.

9. The packaging structure for a soft pack battery according to claim 1, characterized in that: The aluminum-plastic film body is folded along the first central axis so that the first battery cell accommodating cavity and the second battery cell accommodating cavity are combined to form the battery cell accommodating cavity, and the shape of the battery cell accommodating cavity matches the shape of the battery cell for packaging.

10. The packaging structure for a soft pack battery according to claim 9, characterized in that: The battery cell accommodating cavity is in a cylindrical structure.

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