Hot pressing tool

Abstract

The invention relates to the technical field of batteries, and discloses a hot-pressing tool, which is used for packaging a packaging film of a battery cell, and comprises an upper pressing plate, a lower pressing plate, a lower pressing plate, an upper pressing plate and a lower pressing plate, the upper surface of the fixing plate is opposite to the lower surface of the upper pressing plate; in the hot-pressing state, a first hot-pressing area and a second hot-pressing area which are arranged side by side in the length direction of the upper pressing plate are formed between the fixing plate and the upper pressing plate. Wherein a packaging film for wrapping the tab is placed in the first hot pressing area; a packaging film which does not wrap the tab is placed in the second hot pressing area; the multiple protrusions are located in the first hot-pressing area and the second hot-pressing area respectively and are suitable for abutting against the plastic packaging films in all the areas. According to the invention, the plurality of bulges suitable for abutting against the packaging film are arranged on the upper pressing plate, so that the packaging film can be stressed more uniformly during hot-pressing plastic packaging, the problem of poor packaging caused by non-uniform stress of the packaging film is avoided, and the overall quality and stability of cell packaging are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and particularly to a hot pressing tooling. Background Art

[0002] A soft-pack battery mainly consists of a tab, a cell stack, and a packaging film. Among them, the packaging film wraps around the outside of the cell stack and the tab and isolates the two from the external environment. To ensure the sealing of the internal space of the packaging film, a hot pressing device is usually used to seal the opening of the packaging film.

[0003] However, the existing hot pressing devices have relatively high requirements for the flatness of the pressing head. Moreover, with the long-term use of the hot pressing device, the wear generated at the pressing head will cause the flatness of the pressing head to deteriorate further, resulting in uneven force on the pressing head during subsequent hot pressing processes, and further causing poor fitting at the opening of the packaging film, thus affecting the sealing performance of the packaging film. Summary of the Invention

[0004] In view of this, the present invention provides a hot pressing tooling to solve the problem that the sealing performance of the packaging film deteriorates due to insufficient flatness of the pressing head of the existing hot pressing device.

[0005] The present invention provides a hot pressing tooling for the packaging film of a battery cell, comprising:

[0006] An upper pressing plate, with a plurality of protrusions spaced along its length direction provided on the lower surface;

[0007] A fixing plate, with the upper surface opposite to the lower surface of the upper pressing plate;

[0008] In the hot pressing state, a first hot pressing area and a second hot pressing area are formed between the fixing plate and the upper pressing plate, arranged side by side along the length direction of the upper pressing plate; wherein, the packaging film wrapping the tab is placed in the first hot pressing area; the packaging film not wrapping the tab is placed in the second hot pressing area; and a plurality of the protrusions are respectively located in the first hot pressing area and the second hot pressing area and are adapted to abut against the plastic packaging film in each area.

[0009] Beneficial effects: By providing a first hot pressing area and a second hot pressing area between the upper pressing plate and the fixed plate, the hot pressing tooling of the present invention can simultaneously perform hot pressing treatment on the encapsulation film with the tab wrapped and the encapsulation film without the tab wrapped, improving production efficiency. Secondly, by providing a plurality of protrusions on the lower surface of the upper pressing plate, it can ensure sufficient abutment between the lower surface of the upper pressing plate and the encapsulation film in each area, ensuring uniform pressure transfer during the hot pressing and plastic sealing process, improving the fitting degree of the encapsulation film, ensuring the hot pressing quality, reducing encapsulation defects caused by uneven pressure, thereby enhancing the sealing performance of the encapsulation film and the quality reliability of the encapsulated battery cell. Furthermore, compared with the full-surface contact of the existing hot pressing equipment, the surface area of a single protrusion in contact with the encapsulation film is smaller, so the precision requirements for the equipment for processing the protrusions can be reduced. In addition, even during the long-term operation of the hot pressing tooling, if a certain degree of wear appears on the surface of the protrusion, due to the small contact area between the protrusion and the encapsulation film, the change in local flatness will not have a great impact on the overall hot pressing effect. In addition, since the contact area of a single protrusion with the encapsulation film is relatively small, the pressure applied to the plastic sealing film can be increased without changing the applied pressure, thereby enhancing the hot melting and fitting effect of the encapsulation film.

[0010] In an alternative embodiment, the cross-sectional area of the free end of the protrusion is smaller than the cross-sectional area of the fixed end of the protrusion, and the fixed end of the protrusion is connected to the lower surface of the upper pressing plate.

[0011] Beneficial effects: By making the size of the fixed end of the protrusion larger in the present invention, the connection strength between the protrusion and the upper pressing plate can be enhanced. And by making the size of the free end of the protrusion smaller, it is better to control the flatness of the free end of the protrusion, thereby ensuring the fitting effect of the encapsulation film.

[0012] In an alternative embodiment, along the length direction of the upper pressing plate, the length of the free end of the protrusion is L1, and the value range of L1 is 0.3 mm ≤ L1 ≤ 30 mm; along the width direction of the upper pressing plate, the width of the free end of the protrusion is W1, and the value range of W1 is 0.1 mm ≤ W1 ≤ 5 mm.

[0013] Beneficial effects: The reason why the encapsulation film can be fitted and sealed during hot pressing and plastic sealing is that a layer of thermoplastic material layer is provided on the surface of the encapsulation film. The thermoplastic material layer will melt and flow after being heated under pressure. In this way, not only can the opening of the encapsulation film be fitted together, but also the fitting area of the opening of the encapsulation film can be increased, enhancing the sealing effect. Based on this, by setting the protrusion according to the above parameters, on the one hand, it can avoid the size of the free end of the protrusion being too large, facilitating the flow of the thermoplastic material layer in the molten state, reducing the resistance during its flow, and enhancing the conversion ratio of the hot melting head width to the actual melting width; on the other hand, it can also avoid the situation that the encapsulation film is damaged due to the size of the free end of the protrusion being too small.

[0014] In an alternative embodiment, the angle between the side wall of the protrusion and the lower surface of the upper pressing plate is α, and the value range of α is 100° ≤ α ≤ 150°.

[0015] Beneficial effects: Compared with too small an angle, this angle range can avoid the situation where the encapsulation film is damaged due to excessive pressure concentration; on the other hand, compared with too large an angle, this angle range can avoid the interference of the protrusion on the flow of the thermoplastic material layer in the molten state.

[0016] In an alternative embodiment, along the height direction of the protrusion, the projected area of the free end of the protrusion on the upper pressing plate is S, and the value range of S is 0.1 mm 2 ≤ S ≤ 100 mm 2 , the height of the protrusion is t, and the value range of t is 0.03 mm ≤ t ≤ 1 mm; the relationship between t and S satisfies: 0.33 mm ≤ S / t ≤ 170 mm.

[0017] Beneficial effects: By setting the protrusion according to the above parameters, on the one hand, the present invention can avoid the encapsulation film being cracked or punctured due to too small a protrusion, resulting in seal failure; on the other hand, it can avoid the height difference between the free end of the protrusion and the lower surface of the upper pressing plate being too small, so that the lower surface of the upper pressing plate is close to the surface of the pressing head in the existing hot pressing equipment.

[0018] In an alternative embodiment, the plurality of protrusions are divided into at least two groups along the width direction of the upper pressing plate; the protrusions in adjacent two groups correspond to each other and are arranged at intervals along the width direction of the upper pressing plate.

[0019] Beneficial effects: By arranging multiple groups of protrusions in the width direction of the upper pressing plate, the present invention can ensure the conversion ratio of the width of the subsequent hot melt pressing head to the actual melting width, and further ensure the sealing effect of the encapsulation film.

[0020] In an alternative embodiment, along the length direction of the upper pressing plate, the distance between the fixed ends of two adjacent protrusions is L2, and the value range of L2 is 0.1 mm ≤ L2 ≤ 3 mm; along the width direction of the upper pressing plate, the distance between the fixed ends of two adjacent protrusions is W2, and the value range of W2 is 0.1 mm ≤ W2 ≤ 3 mm.

[0021] Beneficial effects: By setting the distance between two adjacent protrusions according to the above parameters, on the one hand, the present invention can avoid difficult processing due to too small a distance; on the other hand, it can avoid being too large, resulting in insufficient hot melt pressure, so that this area cannot be fully hot melted, and thus it is easy to have a peeling problem.

[0022] In an alternative embodiment, the shape of the protrusion is a frustum of a pyramid, a frustum of a cone or a frustum of a triangular pyramid. Beneficial effect: Regardless of the shape of the protrusion, as long as it can ensure uniform pressure transmission during the hot pressing and encapsulation process, improve the adhesion of the encapsulation film, and ensure the hot pressing quality, no specific limitation is made thereto.

[0023] In an alternative embodiment, a groove is provided between the upper pressing plate and the fixing plate, and the first hot pressing area is formed in the groove.

[0024] Beneficial effect: By providing the groove, the operator can quickly determine the placement position of the encapsulation film wrapped with the tab on the hot pressing tooling in a short time, reducing the time consumed for debugging. Secondly, by providing the groove, the encapsulation film without the tab and the encapsulation film wrapped with the tab can be on the same horizontal plane. In this way, during hot pressing, whether it is the part wrapped with the tab or the part without the tab, the pressure borne by the encapsulation film is the same, and the degree of heat melting and flow of the thermoplastic material layer is similar, so that the adhesion and sealing performance of the entire encapsulation film are consistent, improving the quality stability of the battery cell encapsulation.

[0025] In an alternative embodiment, the groove is located on the upper pressing plate and / or the fixing plate.

[0026] Beneficial effect: Regardless of which of the above schemes is adopted for the groove, it is only necessary to ensure that the encapsulation film without the tab and the encapsulation film wrapped with the tab are on the same horizontal plane, and no specific limitation is made thereto. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0028] Figure 1 is a schematic structural diagram of a hot pressing tooling according to an embodiment of the present invention;

[0029] Figure 2 is Figure 1 the bottom view schematic diagram of the upper pressing plate shown in

[0030] Figure 3 is Figure 2 the partial enlarged schematic diagram of A in

[0031] Figure 4 is Figure 2 the schematic structural diagram of the upper pressing plate shown in another perspective;

[0032] Figure 5 For Figure 4 a partially enlarged schematic view of C in

[0033] Figure 6 For Figure 1 the usage state diagram of the hot pressing tooling shown in

[0034] Explanation of reference numerals in the drawings:

[0035] 1. Upper pressing plate; 101. Lower surface; 102. Protrusion; 1021. Free end; 1022. Fixed end; 103. Groove; 2. Fixed plate; 201. Upper surface; 3. First hot pressing area; 4. Second hot pressing area. Detailed implementation manners

[0036] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0037] Aiming at the problem that the sealing performance of the encapsulation film becomes poor due to insufficient flatness of the pressing head in the existing hot pressing equipment, the present invention provides a hot pressing tooling.

[0038] The following will be combined with Figures 1 to 6 to describe the embodiments of the present invention.

[0039] According to an embodiment of the present invention, as Figures 1 to 6 shown, a hot pressing tooling for encapsulating the encapsulation film of an electric core is provided, including: an upper pressing plate 1 and a fixed plate 2.

[0040] Specifically, a plurality of protrusions 102 are provided on the lower surface 101 of the upper pressing plate 1 at intervals in its length direction; the upper surface 201 of the fixed plate 2 is disposed opposite to the lower surface 101 of the upper pressing plate 1; in the hot pressing state, a first hot pressing area 3 and a second hot pressing area 4 are formed between the fixed plate 2 and the upper pressing plate 1 and arranged side by side along the length direction of the upper pressing plate 1; wherein, an encapsulation film wrapping the tab is placed in the first hot pressing area 3; an encapsulation film not wrapping the tab is placed in the second hot pressing area 4; the plurality of protrusions 102 are respectively located in the first hot pressing area 3 and the second hot pressing area 4 and are adapted to abut against the plastic sealing film in each area.

[0041] The hot pressing tooling of this embodiment can simultaneously perform hot pressing on the encapsulation film with and without the tab wrapped by setting the first hot pressing area 3 and the second hot pressing area 4 between the upper pressing plate 1 and the fixed plate 2, improving the production efficiency. Secondly, by arranging a plurality of protrusions 102 on the lower surface 101 of the upper pressing plate 1, it can ensure the full contact between the lower surface 101 of the upper pressing plate 1 and the encapsulation film in each area, ensuring the uniform transmission of pressure during the hot pressing and plastic sealing process, improving the fitting degree of the encapsulation film, ensuring the hot pressing quality, reducing the encapsulation defects caused by uneven pressure, thereby enhancing the sealing performance of the encapsulation film and the quality reliability of the encapsulated battery cell. Moreover, compared with the full-surface contact of the existing hot pressing equipment, the contact surface area between a single protrusion 102 and the encapsulation film is smaller, so the precision requirements for the equipment for processing the protrusions 102 can be reduced. In addition, even during the long-term operation of the hot pressing tooling, if a certain degree of wear appears on the surface of the protrusions 102, due to the small contact area between the protrusions 102 and the encapsulation film, the local flatness change will not have a great impact on the overall hot pressing effect. In addition, since the contact area between a single protrusion 102 and the encapsulation film is relatively small, the pressure applied to the plastic sealing film can be increased without changing the applied pressure, thereby enhancing the hot melting and fitting effect of the encapsulation film.

[0042] It can be understood that to ensure the hot melting and fitting effect of the encapsulation film, the surface of the upper pressing plate 1 facing the fixed plate 2 should be as densely covered with protrusions 102 as possible, so that more protrusions 102 come into contact with the encapsulation film.

[0043] It should be noted that in this embodiment, the encapsulation film can be an aluminum-plastic film. In addition, in this embodiment, the length direction of the upper pressing plate 1 is consistent with Figure 1 the direction shown in

[0044] Specifically, in this embodiment, the hot pressing tooling further includes a mounting base, and the mounting base is located on the side of the fixed plate 2 away from the upper pressing plate 1 and is perpendicularly arranged to the fixed plate 2.

[0045] Specifically, in this embodiment, the protrusions 102 and the upper pressing plate 1 can be integrally formed to ensure the connection strength between the protrusions 102 and the upper pressing plate 1, so that the protrusions 102 can effectively apply the pressure of the upper pressing plate 1 to the encapsulation film.

[0046] It can be understood that the relative positions of the tabs of the battery cell and the electrode group can be flexibly adjusted according to design requirements. Generally, the tabs are arranged at the end of the electrode group and are located at the center position of the end surface of the electrode group. At this time, the number of the second hot pressing areas 4 can be a pair, and along the length direction of the upper pressing plate 1, the first hot pressing area 3 and the second hot pressing area 4 are alternately arranged.

[0047] Specifically, the process of hot pressing and plastic sealing the encapsulation film of the battery cell using the hot pressing tooling of the embodiment of the present invention is as follows:

[0048] First, the electrode group is welded to the external electrode tab of the battery cell through the internal electrode tab. After the welding is completed, the welded electrode group is placed at the pre-set punching position of the upper plastic film. Immediately afterwards, the lower plastic film is covered so that the electrode group is completely wrapped by the upper and lower plastic films. Subsequently, the hot pressing tooling is used to sequentially press the plastic sealing areas on the peripheral sides of the electrode group. At the same time, the heating device is started, and the plastic film is subjected to hot melting and plastic sealing treatment by hot pressing to make the plastic film fit tightly. It can be understood that when hot pressing the plastic film on the side of the electrode group where the electrode tab is provided, the plastic film wrapping the electrode tab needs to be placed in the first hot pressing area 3, and the plastic film not wrapping the electrode tab is placed in the second hot pressing area 4.

[0049] According to an embodiment of the present invention, as Figure 3 and Figure 5 shown, the cross-sectional area of the free end 1021 of the protrusion 102 is smaller than the cross-sectional area of the fixed end 1022 of the protrusion 102, and the fixed end 1022 of the protrusion 102 is connected to the lower surface 101 of the upper pressing plate 1. In this embodiment, the size of the fixed end 1022 of the protrusion 102 is made larger, which can enhance the connection strength between the protrusion 102 and the upper pressing plate 1. And making the size of the free end 1021 of the protrusion 102 smaller can better control the flatness of the free end 1021 of the protrusion 102, thereby ensuring the fitting effect of the plastic film.

[0050] According to an embodiment of the present invention, as Figure 3 shown, along the length direction of the upper pressing plate 1, the length of the free end 1021 of the protrusion 102 is L1, and the value range of L1 is 0.3 mm ≤ L1 ≤ 30 mm; along the width direction of the upper pressing plate 1, the width of the free end 1021 of the protrusion 102 is W1, and the value range of W1 is 0.1 mm ≤ W1 ≤ 5 mm. The reason why the plastic film can be tightly sealed during hot pressing and plastic sealing is that there is a layer of thermoplastic material layer on the surface of the plastic film. The thermoplastic material layer will melt and flow when pressurized and heated. In this way, not only can the opening of the plastic film be fitted together, but also the fitting area at the opening of the plastic film can be increased, improving the sealing effect. Based on this, the present invention sets the protrusion 102 according to the above parameters. On the one hand, it can avoid the size of the free end 1021 of the protrusion 102 from being too large, facilitating the flow of the thermoplastic material layer in the molten state, reducing the resistance during its flow, and improving the conversion ratio of the width of the hot melt pressing head to the actual melting width; on the other hand, it can also avoid the situation that the plastic film is damaged due to the size of the free end 1021 of the protrusion 102 being too small.

[0051] It should be noted that the thermoplastic material layer on the plastic film can be a polypropylene layer (PP layer). In addition, in this embodiment, the length direction and width direction of the upper pressing plate 1 are consistent with the Figure 3 directions shown in

[0052] It can be understood that the value of L1 can be, but is not limited to, 0.3 mm, 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 12 mm, 15 mm, 17 mm, 22 mm, 25 mm, 28 mm, 29 mm, 29.5 mm, 30 mm. The value of W1 can be, but is not limited to, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.5 mm, 0.6 mm, 0.8 mm, 1 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 4.8 mm, 5 mm.

[0053] According to an embodiment of the present invention, as Figure 5 shown, the included angle between the side wall of the protrusion 102 and the lower surface 101 of the upper pressing plate 1 is α, and the value range of α is 100° ≤ α ≤ 150°. Compared with a too small included angle, this angle range can avoid the situation that the encapsulation film is damaged due to excessive pressure concentration; on the other hand, compared with a too large included angle, this angle range can avoid the interference of the protrusion 102 on the flow of the thermoplastic material layer in the molten state.

[0054] It can be understood that the value of α can be, but is not limited to, 100°, 105°, 106°, 107°, 110°, 115°, 120°, 125°, 130°, 135°, 140°, 145°, 150°.

[0055] According to an embodiment of the present invention, along the height direction of the protrusion 102, the orthographic projection area of the free end 1021 of the protrusion 102 on the upper pressing plate 1 is S, and the value range of S is 0.1 mm 2 ≤ S ≤ 100 mm 2 , the height of the protrusion 102 is t, and the value range of t is 0.03 mm ≤ t ≤ 1 mm; the relationship between t and S satisfies: 0.33 mm ≤ S / t ≤ 170 mm. By setting the protrusion 102 according to the above parameters in this embodiment, on the one hand, it can avoid the situation that the encapsulation film is fractured or punctured due to the too small protrusion 102, resulting in seal failure; on the other hand, it can avoid the situation that the height difference between the free end 1021 of the protrusion 102 and the lower surface 101 of the upper pressing plate 1 is too small, so that the lower surface 101 of the upper pressing plate 1 is close to the surface of the pressing head in the existing hot pressing equipment.

[0056] It can be understood that the value of S can be, but is not limited to, 0.1 mm 2 , 0.2 mm 2 , 1 mm 2 , 2 mm 2 , 3 mm 2 , 4 mm 2 , 15 mm 2 , 16 mm2 、17 mm 2 、18 mm 2 、22 mm 2 、25 mm 2 、37 mm 2 、42 mm 2 、55 mm 2 、60 mm 2 、70 mm 2 、88 mm 2 、98 mm 2 、100 mm 2 。The value of t can be, but is not limited to, 0.03 mm, 0.05 mm, 0.08 mm, 0.1 mm, 0.25 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.7 mm, 0.8 mm, 0.95 mm, 1 mm.

[0057] According to an embodiment of the present invention, as shown in Figure 2 and Figure 3 , a plurality of protrusions 102 are divided into at least two groups along the width direction of the upper pressing plate 1; the protrusions 102 in adjacent two groups correspond to each other one by one and are arranged at intervals along the width direction of the upper pressing plate 1. By arranging multiple groups of protrusions 102 in the width direction of the upper pressing plate 1 in this embodiment, it is possible to ensure the conversion ratio of the width of the subsequent hot melt head to the actual melting width, and further ensure the sealing effect of the encapsulation film.

[0058] Preferably, along the width direction of the upper pressing plate 1, the plurality of protrusions 102 are divided into three groups.

[0059] According to an embodiment of the present invention, as shown in Figure 3 , along the length direction of the upper pressing plate 1, the distance between the fixed ends 1022 of two adjacent protrusions 102 is L2, and the value range of L2 is 0.1 mm ≤ L2 ≤ 3 mm; along the width direction of the upper pressing plate 1, the distance between the fixed ends 1022 of two adjacent protrusions 102 is W2, and the value range of W2 is 0.1 mm ≤ W2 ≤ 3 mm. By setting the distance between two adjacent protrusions 102 according to the above parameters in this embodiment, on the one hand, it can avoid the difficulty in processing caused by too small a distance; on the other hand, it can avoid being too large, resulting in insufficient hot melt pressure and making this area not fully melted, thus easily causing peeling problems.

[0060] It can be understood that the value of L2 can be, but is not limited to, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.5 mm, 0.6 mm, 0.8 mm, 1 mm, 2 mm, 2.5 mm, 3 mm. The value of W2 can be, but is not limited to, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.5 mm, 0.6 mm, 0.8 mm, 1 mm, 2 mm, 2.5 mm, 3 mm.

[0061] According to an embodiment of the present invention, as Figure 3 and Figure 5 shown, the shape of the protrusion 102 is a frustum of a trapezoid, a frustum of a cone or a frustum of a triangle. It can be understood that regardless of the shape of the protrusion 102, as long as it can ensure that the pressure can be evenly transmitted during the hot press lamination process, improve the adhesion of the encapsulation film, and ensure the hot press quality, the embodiments of the present invention do not make specific limitations on this.

[0062] According to an embodiment of the present invention, as Figure 1 and Figure 4 shown, a groove 103 is provided between the upper pressing plate 1 and the fixing plate 2, and a first hot pressing area 3 is formed in the groove 103. By providing the groove 103 in this embodiment, it can enable the operator to quickly determine the placement position of the encapsulation film wrapped with the tab on the hot press tooling in a short time, reducing the time consumed for debugging. Secondly, by providing the groove 103, the encapsulation film without the tab and the encapsulation film wrapped with the tab can be on the same horizontal plane. In this way, during hot pressing, whether it is the part wrapped with the tab or the part without the tab, the pressure borne by the encapsulation film is the same, and the degree of heat melting and flow of the thermoplastic material layer is similar, so that the adhesion and sealing performance of the entire encapsulation film are consistent, improving the quality stability of the battery cell encapsulation.

[0063] According to an embodiment of the present invention, as Figure 1 and Figure 4 shown, the groove 103 is located on the upper pressing plate 1 and / or the fixing plate 2. It can be understood that regardless of which of the above schemes is adopted for the groove 103, as long as it can enable the encapsulation film without the tab and the encapsulation film wrapped with the tab to be on the same horizontal plane, the embodiments of the present invention do not make specific limitations on this.

[0064] Preferably, grooves 103 are provided on both sides of the upper pressing plate 1 and the fixing plate 2 facing each other, and the grooves 103 on the upper pressing plate 1 and the grooves 103 on the fixing plate 2 are arranged oppositely. During the hot press lamination process, the two oppositely arranged grooves 103 together form the first hot pressing area 3 for accommodating the encapsulation film wrapped with the tab.

[0065] The technical effects of the technical solutions of the present invention will be described below in combination with specific embodiments and comparative examples.​

[0066] Table 1

[0067]

[0068]

[0069] It can be seen that by setting L1, W1, L2, W2, S, t and S / t according to the parameters limited in the embodiments of the present invention, not only can the hot pressing and plastic sealing effect of the hot pressing tooling on the packaging film be ensured, and the sealing performance of the packaging film be guaranteed; at the same time, the service life of the hot pressing tooling can be extended, and the product qualification rate can be guaranteed.

[0070] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations fall within the scope defined by the appended claims.

Claims

1. A hot pressing tool for packaging a packaging film for a battery cell, characterized in that: include: The upper pressing plate has a plurality of protrusions arranged at intervals in the length direction on the lower surface; A fixing plate, the upper surface of which is arranged opposite to the lower surface of the upper pressing plate; Under the hot pressing state, a first hot pressing zone and a second hot pressing zone are formed between the fixed plate and the upper pressing plate, which are arranged side by side along the length direction of the upper pressing plate; wherein a packaging film wrapping the pole ear is placed in the first hot pressing zone; a packaging film not wrapping the pole ear is placed in the second hot pressing zone; the plurality of protrusions are respectively located in the first hot pressing zone and the second hot pressing zone and are suitable for abutting against the packaging film in each area.

2. The hot pressing tooling according to claim 1, characterized in that: The cross-sectional area of ​​the free end of the protrusion is smaller than the cross-sectional area of ​​the fixed end of the protrusion, and the fixed end of the protrusion is connected to the lower surface of the upper pressing plate.

3. The hot pressing tooling according to claim 2, characterized in that: Along the length direction of the upper pressing plate, the length of the free end of the protrusion is L1, and the value range of L1 is 0.3mm≤L1≤30mm; along the width direction of the upper pressing plate, the width of the free end of the protrusion is W1, and the value range of W1 is 0.1mm≤W1≤5mm.

4. The hot pressing tooling according to claim 2, characterized in that: The angle between the side wall of the protrusion and the lower surface of the upper pressing plate is α, and the value range of α is 100°≤α≤150°.

5. The hot pressing tool according to claim 1, characterized in that: Along the height direction of the protrusion, the orthographic projection area of ​​the free end of the protrusion toward the upper pressing plate is S, and the value range of S is 0.1mm 2 ≤S≤100mm 2 , the height of the protrusion is t, the value range of t is 0.03mm≤t≤1mm; the relationship between t and S satisfies: 0.33mm≤S / t≤170mm.

6. The hot pressing tool according to claim 1, characterized in that: The plurality of protrusions are divided into at least two groups along the width direction of the upper pressing plate; the protrusions in two adjacent groups correspond to each other one by one and are arranged at intervals along the width direction of the upper pressing plate.

7. The hot pressing tool according to claim 5, characterized in that: Along the length direction of the upper pressing plate, the distance between the fixed ends of two adjacent protrusions is L2, and the value range of L2 is 0.1mm≤L2≤3mm; along the width direction of the upper pressing plate, the distance between the fixed ends of two adjacent protrusions is W2, and the value range of W2 is 0.1mm≤W2≤3mm.

8. The hot pressing tool according to any one of claims 1 to 7, characterized in that: The shape of the protrusion is a trapezoidal platform, a circular platform or a triangular platform.

9. The hot pressing tool according to any one of claims 1 to 7, characterized in that: A groove is provided between the upper pressing plate and the fixing plate, and the first hot pressing zone is formed in the groove.

10. The hot pressing tool according to claim 9, characterized in that: The groove is located on the upper pressing plate and / or the fixing plate.

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