Packaging method of main-grid-free battery assembly and main-grid-free battery assembly
By using infrared LED light boxes for welding and heating lamination in main gateless battery modules, the gate breaking problem caused by low thermal conductivity of secondary gate slurry is solved, reducing welding difficulty and improving welding efficiency.
Patent Information
- Application Number
- CN202411234934.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-04
- Publication Date
- 2024-12-13
AI Technical Summary
During welding, the main gateless battery module is prone to grid breakage due to the low thermal conductivity of the secondary gate slurry, which increases the difficulty of welding.
Each PAD point is welded using an infrared LED light box to form a battery string, and the welding tape and the secondary gate are connected to the secondary gate through heating lamination to reduce the welding temperature and avoid excessive heating of the secondary gate.
It effectively reduces the risk of gate breakage during welding of main gateless battery modules, reduces welding difficulty, and does not require changes to the existing process flow.
Smart Images
Figure CN119133314A_ABST
Abstract
Description
Technical Field
[0001] The present application mainly relates to the field of photovoltaic cell technology, and in particular to a packaging method for a busbar-free cell assembly and a busbar-free cell assembly. Background Art
[0002] When welding a busbar-less battery module, the welding ribbon is pressed tightly against the PAD point and the auxiliary grid, and a high-power lamp is used to continuously heat the welding. The thermal conductivity of the slurry used in the auxiliary grid is lower than that used in the PAD point, and the grid is prone to breakage during the welding process, making welding more difficult. Summary of the invention
[0003] The purpose of the present application is to provide a packaging method for a busbarless battery assembly and a busbarless battery assembly, which are used to overcome the problems of busbar breakage and the like that are easily occurred in the existing busbarless battery assemblies, so as to reduce the difficulty of welding the busbarless battery assembly.
[0004] In a first aspect, the present application provides a packaging method for a main-grid-free battery assembly, comprising: configuring PAD points and sub-grids on multiple battery cells, and providing welding strips for connecting the PAD points on the multiple battery cells; welding each PAD point by means of LED lamp beads in an infrared LED light box to obtain multiple battery strings, wherein the setting position of each LED lamp bead corresponds to the projection position of a PAD point along the height direction of the light box; laying out the multiple battery strings to form a battery assembly; and heating and laminating the battery assembly to form an alloy connection between the welding strip and the sub-grid.
[0005] In some embodiments, the distance between the setting position of the center point of each LED lamp bead and the projection position of the center point of the corresponding PAD point is less than 5 mm.
[0006] In some embodiments, the difference between the size of each LED lamp bead and the size of the corresponding PAD point is less than 5 mm.
[0007] In some embodiments, the melting point of the solder tape is 136°C-143°C, and the temperature of the heated lamination is 150°C.
[0008] In some embodiments, the solder ribbon includes an outer coating layer and an inner coating layer, wherein the solder of the outer coating layer is a low-temperature solder, and the solder of the inner coating layer is a high-temperature solder.
[0009] In some embodiments, the temperature of the heating lamination is not higher than the melting point of the high temperature solder, and the temperature of the heating lamination is not lower than the melting point of the low temperature solder.
[0010] In the second aspect, the present application provides a main-grid-free battery assembly, comprising: a plurality of battery cells, each of which is provided with a PAD point and a sub-grid, and each of which is provided with a welding strip for connecting the PAD points, wherein the projection position of each PAD point along the height direction of the light box corresponds to the setting position of an LED lamp bead in the infrared LED light box, and the welding strip forms an alloy connection with the sub-grid.
[0011] In some embodiments, the distance between the projection position of the center point of each PAD point and the setting position of the center point of the corresponding LED lamp bead is less than 5 mm.
[0012] In some embodiments, the difference between the size of each PAD point and the size of the corresponding LED lamp bead is less than 5 mm.
[0013] In some embodiments, the melting point of the soldering tape is 136°C-143°C; the soldering tape and the auxiliary grid form an alloy connection during heating and lamination, and the temperature of the heating and lamination is 150°C.
[0014] In some embodiments, the solder ribbon includes an outer coating layer and an inner coating layer, wherein the solder of the outer coating layer is a low-temperature solder, and the solder of the inner coating layer is a high-temperature solder.
[0015] In some embodiments, the temperature of the heating lamination is not higher than the melting point of the high temperature solder, and the temperature of the heating lamination is not lower than the melting point of the low temperature solder.
[0016] In a third aspect, the present application provides a busbar-less battery assembly, wherein the busbar-less battery assembly is obtained by the packaging method of the busbar-less battery assembly as described in any one of the first aspects above.
[0017] Compared with the prior art, this application has the following advantages:
[0018] The present application provides a packaging method for a main-grid-free battery assembly and a main-grid-free battery assembly. Each PAD point is welded by each LED lamp bead in an infrared LED light box to obtain multiple battery strings. The setting position of each LED lamp bead in the infrared LED light box corresponds to the projection position of a PAD point along the height direction of the light box, thereby eliminating the need to heat the light box with a secondary grid, thereby reducing the risk of the secondary grid being broken in the infrared LED light box. Then, the formed battery assembly is heated and laminated to form an alloy connection with the secondary grid. Since the lamination process can lower the temperature relative to the infrared LED light box, the present method can lower the welding temperature of the secondary grid, thereby reducing the risk of the main-grid-free battery assembly being broken during welding. There is no need to change the existing process flow, thereby reducing the difficulty of welding the main-grid-free battery assembly. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The accompanying drawings are included to provide a further understanding of the present application. They are included and constitute a part of the present application. The accompanying drawings illustrate embodiments of the present application and together with the present specification serve to explain the principles of the present application. In the accompanying drawings:
[0020] Figure 1 It is a flow chart of a packaging method of a busbar-free battery assembly provided in an embodiment of the present application;
[0021] Figure 2 is an exemplary diagram of a battery cell provided in an embodiment of the present application;
[0022] Figure 3 This is an example diagram of an infrared LED light box provided in an embodiment of the present application;
[0023] Figure 4 This is an example diagram of a welding strip provided in an embodiment of the present application;
[0024] Figure 5 This is an example diagram of a busbar-free battery assembly provided in an embodiment of the present application. DETAILED DESCRIPTION
[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.
[0026] As shown in this application and claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.
[0027] In addition, it should be noted that the use of words such as "first" and "second" to define components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above words have no special meaning and cannot be understood as limiting the scope of protection of this application. In addition, although the terms used in this application are selected from well-known and commonly used terms, some terms mentioned in the specification of this application may be selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant parts of the description of this article. In addition, it is required to understand this application not only by the actual terms used, but also by the meaning implied by each term.
[0028] The technical concept of this application is as follows:
[0029] The existing busbar-free solar cell assembly (such as HJT solar cell) welding area metallization design generally removes the busbar connection line, leaving the PAD point and the secondary grid welding area, so the welding of the busbar-free solar cell assembly mainly includes PAD point welding and secondary grid welding. The PAD point is usually printed with pure silver paste and is relatively large in size, while the secondary grid is usually printed with silver-coated copper paste and is much smaller than the PAD point. After the soldering ribbon is pressed tightly against the PAD point and the secondary grid, it is heated with a high-power lamp.
[0030] This welding method has some problems, such as: in order to ensure the welding tension at the PAD point, the lamp needs to be maintained at a higher power or the heating time needs to be extended to increase the fluidity of the solder, resulting in higher welding energy consumption. In addition, since the thermal conductivity of the slurry at the secondary grid is not as good as that at the PAD point, the main grid-free battery assembly may be broken during the lamp heating process, making welding more difficult.
[0031] In view of this, the embodiments of the present application aim to provide a packaging method for a busbarless battery assembly and a busbarless battery assembly. By using a specific infrared LED light box to avoid excessive heating of the slurry at the secondary grid, problems such as broken grid that are prone to exist in the existing welding process can be solved without changing the existing process flow, thereby reducing the difficulty of welding the busbarless battery assembly.
[0032] Figure 1 A flow chart of a method for packaging a busbar-free battery assembly provided in an embodiment of the present application.
[0033] refer to Figure 1 , specifically including the following steps:
[0034] S1, configuring PAD points and sub-grids on multiple battery cells, and providing welding strips for connecting the PAD points on the multiple battery cells.
[0035] S2, welding each PAD point through each LED lamp bead in the infrared LED light box to obtain multiple battery strings, wherein the setting position of each LED lamp bead corresponds to the projection position of a PAD point along the height direction of the light box.
[0036] S3, layout the multiple battery strings so that the multiple battery strings form a battery assembly.
[0037] S4, heating and laminating the battery assembly so that the welding strip and the auxiliary grid form an alloy connection.
[0038] Figure 2 This is an example diagram of a battery cell provided in an embodiment of the present application. Figure 2, the battery cell is configured with a plurality of PAD points 21 and a plurality of sub-grids 22. The PAD points 21 are configured on four of the sub-grids 22 of the battery cell. Each sub-grid 22 extends along the horizontal direction (x direction) of the battery cell. The PAD points 21 are arranged at intervals along the vertical direction (y direction) of the battery cell, wherein there is a gap 23 between every two adjacent PAD points 21 along the vertical direction of the battery cell. There are multiple sub-grids 22 between the gaps 23. The position of the sub-grid 22 corresponding to the PAD point along the vertical direction of the battery cell is the welding point of the sub-grid 22. Similarly, there is a gap 24 between every two adjacent PAD points 21 along the horizontal direction (x direction) of the battery cell, and multiple PAD points 21 are arranged at intervals on the same sub-grid 22.
[0039] Figure 3 This is an example diagram of an infrared LED light box provided in an embodiment of the present application. Figure 3 The infrared LED light box includes a plurality of LED lamp beads 31. A gap 32 exists between every two adjacent LED lamp beads 31 along the length direction (y direction) of the light box, and a gap 33 exists between every two adjacent LED lamp beads 31 along the width direction (x direction) of the light box. The distance between each gap 23 and each gap 32 is consistent, and the distance between each gap 24 and each gap 33 is consistent, so that the setting position of each LED lamp bead 31 corresponds to the projection position of a PAD point 21 along the height direction of the light box (not shown in the figure).
[0040] In some embodiments, the welding strip is arranged along the vertical direction of the battery cell, and is used to connect each PAD point 21 and each sub-grid 22. After the welding strip is pressed tightly against the PAD point 21 and the sub-grid 22, the battery cell is placed in the above-mentioned infrared LED light box, and each PAD point 21 is welded by each LED lamp bead 31 in the infrared LED light box, and then multiple battery strings are formed into a battery assembly, and then the battery assembly is heated and laminated, so that the welding strip and the sub-grid 22 form an alloy connection. Therefore, the welding at the PAD point 21 is carried out separately from the welding at the sub-grid 22. In the infrared LED light box, since the setting position of each LED lamp bead 31 corresponds to the projection position of a PAD point 21 along the height direction of the light box, the temperature at the sub-grid 22 is lower than the temperature when the PAD point 21 is heated, and since the welding at the sub-grid 22 is carried out by heating and laminating, the temperature of the lamination process can be lowered relative to the infrared LED light box, and only needs to reach the melting point of the solder, so the welding temperature of the sub-grid 22 is reduced, thereby reducing the risk of broken grids in the main grid-free battery assembly.
[0041] Continue to refer Figure 2 , Figure 3In some embodiments, the distance between the setting position of the center point of each LED lamp bead 31 and the projection position of the center point of the corresponding PAD point 21 is less than 5 mm. And the difference between the size of each LED lamp bead 31 and the size of the corresponding PAD point 21 is less than 5 mm.
[0042] In some embodiments, the soldering tape may use a low-temperature soldering tape, for example, a soldering tape made of Sn37Pb37Bi26. Preferably, the melting point of the soldering tape is 136°C-143°C, and the temperature of the heating lamination is 150°C. Therefore, the solder will melt on the soldering tape during the heating lamination, while the paste of the auxiliary grid 22 will not be affected, thereby reducing the risk of grid breakage on the cell.
[0043] In some embodiments, the soldering tape may use a double-coated soldering tape. Figure 4 The solder strip may include an outer coating 41 and an inner coating 42, wherein the solder of the outer coating 41 is a low-temperature solder and the solder of the inner coating 42 is a high-temperature solder. The inner coating 42 wraps the solder strip copper core layer 43, and the outer coating 41 wraps the inner coating 42, so that the solder strip forms a layered structure from the inside to the outside.
[0044] Preferably, the temperature of the heating lamination is not higher than the melting point of the high temperature solder, and the temperature of the heating lamination is not lower than the melting point of the low temperature solder. The melting point of the low temperature solder may be 136-143°C, and the temperature of the heating lamination is about 150°C. The melting point of the high temperature solder is higher than 150°C.
[0045] In step S2, since the temperature in the infrared LED light box is higher than the melting point of the low-temperature solder and higher than the melting point of the high-temperature solder, effective welding of the PAD point 21 can be achieved. Compared with the single-coated solder strip, the joint use of the high-temperature solder and the low-temperature solder can increase the fluidity of the solder, thereby increasing the welding tension between the PAD point and the solder strip. In step S4, since the temperature of the heated lamination is higher than the melting point of the low-temperature solder but lower than the melting point of the high-temperature solder, an alloy connection is formed between the low-temperature solder and the auxiliary grid 22, and the high-temperature solder does not participate in the alloying, thereby avoiding the broken grid at the auxiliary grid 22 due to the high fluidity of the high-temperature solder.
[0046] Furthermore, the present application provides a busbar-free battery assembly, comprising: a plurality of battery cells, each of which is referred to as Figure 5 As shown. Each cell is provided with a PAD point 51 and a secondary grid 52, and is also provided with a welding strip 53 for connecting the PAD point 51. The projection position of each PAD point 51 along the height direction of the light box corresponds to the setting position of an LED lamp bead in the infrared LED light box, so in the infrared LED light box, the welding strip 53 is first welded to the PAD point 51. The structure of the infrared LED light box can refer to Figure 3, which will not be described in detail here. Accordingly, the location of each LED lamp bead will not correspond to the projection location of the auxiliary grid 52 along the height direction of the light box, so the temperature of the auxiliary grid 52 in the infrared LED light box will not easily cause it to be welded with the welding strip 53, so that the required alloy connection between the auxiliary grid 52 and the welding strip 53 can be formed during the heating lamination, thereby improving the broken grid problem in the existing main grid-free battery assembly.
[0047] In some embodiments, the distance between the projection position of the center point of each PAD point 51 and the setting position of the center point of the corresponding LED lamp bead is less than 5 mm.
[0048] In some embodiments, the difference between the size of each PAD point 51 and the size of the corresponding LED lamp bead is less than 5 mm.
[0049] In some embodiments, the melting point of the soldering ribbon 53 is 136° C.-143° C.; the soldering ribbon 53 and the auxiliary grid 52 form an alloy connection during heating and lamination, and the temperature of heating and lamination is 150° C.
[0050] In some embodiments, the solder strip 53 includes an outer coating and an inner coating, wherein the solder of the outer coating is low temperature solder and the solder of the inner coating is high temperature solder. The temperature of the heating lamination is not higher than the melting point of the high temperature solder and not lower than the melting point of the low temperature solder.
[0051] Furthermore, the present application provides a main grid-free battery assembly, which is composed of the above-mentioned Figure 1 The packaging method of the main grid-free battery module is obtained.
[0052] The present application provides a packaging method for a main-grid-free battery assembly and a main-grid-free battery assembly. Each PAD point is welded by each LED lamp bead in an infrared LED light box to obtain multiple battery strings. The setting position of each LED lamp bead in the infrared LED light box corresponds to the projection position of a PAD point along the height direction of the light box, thereby eliminating the need to heat the light box with a secondary grid, thereby reducing the risk of the secondary grid being broken in the infrared LED light box. Then, the formed battery assembly is heated and laminated to form an alloy connection with the secondary grid. Since the lamination process can lower the temperature relative to the infrared LED light box, the present method can lower the welding temperature of the secondary grid, thereby reducing the risk of the main-grid-free battery assembly being broken during welding. There is no need to change the existing process flow, thereby reducing the difficulty of welding the main-grid-free battery assembly.
[0053] The basic concepts have been described above. Obviously, for those skilled in the art, the above application disclosure is only an example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.
[0054] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.
[0055] Similarly, it should be noted that in order to simplify the description of the disclosure of this application and thus help understand one or more application embodiments, in the above description of the embodiments of this application, multiple features are sometimes merged into one embodiment, figure or description thereof. However, this disclosure method does not mean that the features required by the object of this application are more than the features mentioned in the claims. In fact, the features of the embodiments are less than all the features of the single embodiment disclosed above.
[0056] In some embodiments, numbers describing the number of components and attributes are used. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise specified, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may change according to the required features of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining digits. Although the numerical domains and parameters used to confirm the breadth of their range in some embodiments of the present application are approximate values, in specific embodiments, the setting of such numerical values is as accurate as possible within the feasible range.
[0057] Although the present application has been described with reference to the current specific embodiments, ordinary technicians in this technical field should recognize that the above embodiments are only used to illustrate the present application, and various equivalent changes or substitutions may be made without departing from the spirit of the present application. Therefore, as long as the changes and modifications to the above embodiments are within the essential spirit of the present application, they will fall within the scope of the claims of the present application.
Claims
1. A method for packaging a busbar-free battery assembly, characterized in that: include: Arrange PAD points and auxiliary grids on a plurality of battery cells, and provide welding strips for connecting the PAD points on the plurality of battery cells; Each PAD point is welded by each LED lamp bead in the infrared LED light box to obtain a plurality of battery strings, wherein the setting position of each LED lamp bead corresponds to the projection position of a PAD point along the height direction of the light box; Arrange the plurality of battery strings so that the plurality of battery strings form a battery assembly; The battery assembly is heated and laminated so that the welding strip and the auxiliary grid form an alloy connection.
2. The packaging method according to claim 1, characterized in that: The distance between the setting position of the center point of each LED lamp bead and the projection position of the center point of the corresponding PAD point is less than 5 mm.
3. The packaging method according to claim 1, characterized in that: The difference between the size of each LED lamp bead and the size of the corresponding PAD point is less than 5mm.
4. The packaging method according to claim 1, characterized in that: The melting point of the solder strip is 136°C-143°C, and the temperature of the heating lamination is 150°C.
5. The packaging method according to claim 1, characterized in that: The solder strip comprises an outer coating and an inner coating, wherein the solder of the outer coating is a low-temperature solder, and the solder of the inner coating is a high-temperature solder.
6. The packaging method according to claim 5, characterized in that: The temperature of the heating lamination is not higher than the melting point of the high temperature solder, and the temperature of the heating lamination is not lower than the melting point of the low temperature solder.
7. A busbar-free battery assembly, characterized in that: include: A plurality of battery cells are provided with PAD points and sub-grids, and a welding strip for connecting the PAD points is provided on the plurality of battery cells, wherein the projection position of each PAD point along the height direction of the light box corresponds to the setting position of an LED lamp bead in the infrared LED light box, and the welding strip forms an alloy connection with the sub-grid.
8. The busbar-free battery assembly according to claim 7, characterized in that: The distance between the projection position of the center point of each PAD point and the setting position of the center point of the corresponding LED lamp bead is less than 5mm.
9. The busbar-free battery assembly according to claim 7, characterized in that: The difference between the size of each PAD point and the size of the corresponding LED lamp bead is less than 5mm.
10. The busbar-free battery assembly according to claim 7, characterized in that: The melting point of the soldering tape is 136°C-143°C; the soldering tape and the auxiliary grid form an alloy connection during heating and lamination, and the temperature of the heating and lamination is 150°C.
11. The busbar-free battery assembly according to claim 7, characterized in that: The solder strip comprises an outer coating and an inner coating, wherein the solder of the outer coating is a low-temperature solder, and the solder of the inner coating is a high-temperature solder.
12. The busbar-free battery assembly according to claim 11, characterized in that: The temperature of the heating lamination is not higher than the melting point of the high temperature solder, and the temperature of the heating lamination is not lower than the melting point of the low temperature solder.
13. A busbar-free battery assembly, characterized in that: The busbar-free battery assembly is obtained by the packaging method of the busbar-free battery assembly according to any one of claims 1-6.