IBC battery assembly and manufacturing method thereof

Abstract

The present application discloses an IBC battery assembly, including a substrate, a first adhesive film layer, a battery cell layer, a second adhesive film layer, and a glass substrate stacked in sequence from bottom to top, the battery cell layer including multiple battery strings, each battery string including multiple IBC batteries and a conductive pressure-sensitive adhesive tape for connecting adjacent IBC batteries; the conductive pressure-sensitive adhesive tape includes a stacked base layer and a conductive pressure-sensitive adhesive layer, the back of the IBC battery is distributed with a first electrode and a second electrode arranged in parallel at intervals, and the first and second electrodes of adjacent IBC batteries are arranged in opposite order, and the conductive pressure-sensitive adhesive layer is connected to the first and second electrodes of adjacent IBC batteries. Adjacent batteries are connected by conductive pressure-sensitive adhesive tape, which will not generate thermal stress and can reduce the probability of hidden cracks or fragments; when hidden cracks or fragments occur, the conductive pressure-sensitive adhesive tape can be uncovered for repair, which is simple and reliable; and is suitable for the development of thin-film batteries. The present application also provides a method for manufacturing an assembly with the above advantages.

Description

Technical Field

[0001] The present application relates to the technical field of solar cells, and in particular to an IBC battery assembly and a method for manufacturing the same. Background Art

[0002] IBC (Interdigitated Back Contact) cells are solar cells with back-contact and positive and negative metal electrodes arranged in a cross-finger pattern on the back of the cell. The PN junction is located on the back of the cell. Because the front of the cell is unobstructed, optical losses are reduced, and it has higher power generation efficiency and is beautiful, making it the focus of research and development.

[0003] When IBC batteries are connected in series, they can be welded using traditional welding strips or encapsulated using conductive backplanes. When using traditional welding strips, welding needs to be performed at a high temperature of about 320℃ to 380℃. IBC batteries are easily bent by the stress generated by high-temperature welding, resulting in hidden cracks or fragments. The technology of encapsulating using conductive backplanes is very complex and is not conducive to rework and mass production.

[0004] Therefore, how to solve the above technical problems should be the focus of technical personnel in this field. Summary of the invention

[0005] The purpose of the present application is to provide an IBC battery assembly and a method for manufacturing the same, so as to reduce the occurrence of hidden cracks or fragments of IBC batteries in the IBC battery assembly, and at the same time facilitate repair once hidden cracks or fragments occur in the IBC batteries.

[0006] In order to solve the above technical problems, the present application provides an IBC battery assembly, comprising a substrate, a first adhesive film layer, a battery layer, a second adhesive film layer, and a glass substrate stacked in sequence from bottom to top, wherein the battery layer comprises a plurality of battery strings, each of which comprises a plurality of IBC batteries and a conductive pressure-sensitive tape for connecting adjacent IBC batteries;

[0007] The conductive pressure-sensitive adhesive tape includes a stacked base layer and a conductive pressure-sensitive adhesive layer. The back of the IBC battery is provided with a first electrode and a second electrode that are spaced apart and arranged in parallel. The first electrode and the second electrode of adjacent IBC batteries are arranged in opposite order. The conductive pressure-sensitive adhesive layer is connected to the first electrode and the second electrode of adjacent IBC batteries.

[0008] Optionally, both the first electrode and the second electrode are segmented electrodes.

[0009] Optionally, the conductive pressure-sensitive adhesive layer in the IBC battery assembly includes any one of a conductive filler, an adhesive, a rubber and a modified resin.

[0010] Optionally, the conductive filler in the IBC battery assembly is a silver filler or a copper filler.

[0011] Optionally, the first adhesive film layer and the second adhesive film layer are both EVA adhesive film layers or both POE adhesive film layers.

[0012] Optionally, the glass substrate is ultra-white patterned glass.

[0013] Optionally, the IBC battery is any one of a whole-piece IBC battery, a half-piece IBC battery, and a three-part IBC battery.

[0014] Optionally, the substrate is a glass plate or a back plate.

[0015] The present application also provides a method for manufacturing an IBC battery assembly, comprising:

[0016] A plurality of prepared IBC batteries, substrates, a first adhesive film layer, a second adhesive film layer, and a glass substrate are obtained, wherein the back of the IBC battery is provided with a first electrode and a second electrode spaced and arranged in parallel;

[0017] The IBC batteries in which the first electrodes and the second electrodes are arranged in opposite order are arranged alternately, and the first electrodes and the second electrodes of adjacent IBC batteries are connected by a conductive pressure-sensitive tape to obtain a battery layer;

[0018] The substrate, the first adhesive film layer, the battery layer, the second adhesive film layer, and the glass substrate are stacked in sequence, and vacuumized using a laminator, and laminated at a temperature of 140° C. to 150° C. to obtain an IBC battery assembly.

[0019] The IBC battery assembly provided in the present application includes a substrate, a first adhesive film layer, a battery cell layer, a second adhesive film layer, and a glass substrate stacked in sequence from bottom to top, the battery cell layer includes multiple battery strings, each battery string includes multiple IBC batteries and a conductive pressure-sensitive tape for connecting adjacent IBC batteries; the conductive pressure-sensitive tape includes a stacked base layer and a conductive pressure-sensitive adhesive layer, the back of the IBC battery is distributed with a first electrode and a second electrode arranged in parallel at an interval, and the first electrode and the second electrode of adjacent IBC batteries are arranged in opposite order, and the conductive pressure-sensitive adhesive layer is connected to the first electrode and the second electrode of adjacent IBC batteries.

[0020] It can be seen that the adjacent IBC batteries in the IBC battery assembly in the present application are connected by conductive pressure-sensitive tape, and no high-temperature welding is required, so the IBC battery will not be subjected to thermal stress caused by welding, thereby reducing the probability of hidden cracks or fragments in the IBC battery; once hidden cracks or fragments appear, due to the stickiness of the conductive pressure-sensitive tape, the conductive pressure-sensitive tape can be peeled off at any time for repair before the IBC battery assembly is laminated, which is very simple and reliable, and will not affect the secondary use of the conductive pressure-sensitive tape, and is suitable for mass production; at the same time, the thickness of the IBC battery has no effect on the use of the conductive pressure-sensitive tape for connection, which is more suitable for the development of IBC batteries in the direction of thinning. In addition, the present application also provides a method for manufacturing an IBC battery assembly with the above advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions of the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 A schematic diagram of the structure of an IBC battery assembly provided in an embodiment of the present application;

[0023] Figure 2 It is a schematic diagram of the structure of the IBC battery interconnection in the IBC battery assembly;

[0024] Figure 3 It is a schematic diagram of the structure of two adjacent IBC batteries;

[0025] Figure 4 This is a schematic diagram of the structure of half-cell IBC battery interconnection;

[0026] Figure 5 It is a schematic diagram of the structure of the interconnection of IBC batteries divided into three equal parts;

[0027] Figure 6 It is a schematic diagram of the structure of the conductive pressure-sensitive tape;

[0028] Figure 7 A flow chart of a method for manufacturing an IBC battery assembly provided in an embodiment of the present application;

[0029] In the figure: 1. glass substrate, 2. second adhesive film layer, 3. battery cell layer, 4. first adhesive film layer, 5. substrate, 6. first electrode, 7. second electrode, 31. IBC battery, 32. conductive pressure-sensitive adhesive tape, 321. base layer, 322. conductive pressure-sensitive adhesive layer. DETAILED DESCRIPTION

[0030] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0031] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0032] As described in the background technology section, the current IBC battery assembly uses welding ribbons or conductive backplanes to connect IBC batteries. When using traditional welding ribbons, welding needs to be performed at a high temperature of about 320°C to 380°C. The IBC battery is affected by the stress generated by high-temperature welding and is prone to bending, causing hidden cracks or fragments. The technology of packaging using a conductive backplane is very complicated and is not conducive to rework and mass production.

[0033] In view of this, the present application provides an IBC battery assembly, please refer to Figure 1 and Figure 2 , Figure 1 A schematic diagram of the structure of an IBC battery assembly provided in an embodiment of the present application, Figure 2 Schematic diagram of the structure of the interconnection of IBC batteries in an IBC battery assembly, the IBC battery assembly includes a substrate 5, a first adhesive film layer 4, a battery layer 3, a second adhesive film layer 2, and a glass substrate 1 stacked in sequence from bottom to top, the battery layer 3 includes a plurality of battery strings, each of which includes a plurality of IBC batteries 31 and a conductive pressure-sensitive adhesive tape 32 for connecting adjacent IBC batteries 31;

[0034] The conductive pressure-sensitive adhesive tape 32 includes a stacked base layer 321 and a conductive pressure-sensitive adhesive layer 322. The back of the IBC battery 31 is provided with a first electrode 6 and a second electrode 7 that are spaced apart and arranged in parallel. The first electrode 6 and the second electrode 7 of adjacent IBC batteries 31 are arranged in opposite order. The conductive pressure-sensitive adhesive layer 322 is connected to the first electrode 6 and the second electrode 7 of adjacent IBC batteries 31.

[0035] The IBC battery 31 in the IBC battery assembly generally adopts an N-type silicon substrate, the area where the first electrode 6 is located is heavily doped with P type, and the area where the second electrode 7 is located is heavily doped with N type. In order to insulate the first electrode 6 and the second electrode 7 from each other, a silicon oxide or silicon nitride passivation film is provided on the back of the N-type silicon substrate.

[0036] In this embodiment, the first electrodes 6 and the second electrodes 7 of adjacent IBC batteries 31 are arranged in opposite order and have the same number of columns, that is, at the same position of adjacent IBC batteries 31, one IBC battery 31 has the first electrode 6 and the other IBC battery 31 has the second electrode 7, see Figure 3 shown.

[0037] Optionally, the IBC battery 31 in this embodiment is any one of a whole IBC battery 31, a half IBC battery 31, and a three-part IBC battery 31, and can also be an IBC battery 31 with smaller parts, such as four parts, five parts, etc. When the IBC battery 31 is a half IBC battery 31 or a three-part IBC battery 31, please refer to the interconnection structure diagram of the IBC battery 31. Figure 4 and Figure 5 .

[0038] It should be noted that in this embodiment, the specific types of the first electrode 6 and the second electrode 7 are not specifically limited and depend on the situation. For example, when the first electrode 6 is a positive electrode, the second electrode 7 is a negative electrode; when the first electrode 6 is a negative electrode, the second electrode 7 is a positive electrode.

[0039] See the schematic diagram of the structure of the conductive pressure sensitive tape 32. Figure 6 , wherein the conductive pressure-sensitive adhesive layer 322 in the IBC battery assembly includes any one of conductive fillers, adhesives, rubber and modified resins; the base layer 321 is a PET (polyethylene terephthalate) film layer. The thickness of the PET film layer is very thin and can be melted at a temperature of 140°C to 150°C, thereby achieving conduction between adjacent IBC batteries 31.

[0040] It should be noted that the type of modified resin is not specifically limited in this embodiment and can be set at will. For example, the modified resin can be an acrylic modified resin, or an organic silicon modified resin, or an epoxy silicon modified resin.

[0041] Furthermore, the conductive filler in the IBC battery assembly is a silver filler or a copper filler, or a silver-coated nickel filler, etc.

[0042] Preferably, both the first electrode 6 and the second electrode 7 are segmented electrodes, which can reduce the amount of silver paste used and reduce costs.

[0043] Optionally, the first adhesive film layer 4 and the second adhesive film layer 2 are both EVA (Ethylene VinylAcetate, ethylene-vinyl acetate copolymer) adhesive film layers or both POE (ethylene-octene copolymer) adhesive film layers.

[0044] In the present embodiment, adjacent IBC batteries 31 in the IBC battery assembly are connected by conductive pressure-sensitive tape 32, and high-temperature welding is not required. Therefore, the IBC battery 31 will not be subjected to thermal stress caused by welding, thereby reducing the probability of hidden cracks or fragments in the IBC battery 31; once hidden cracks or fragments occur, since the conductive pressure-sensitive tape 32 is sticky, the conductive pressure-sensitive tape 32 can be peeled off at any time for repair before the IBC battery assembly is laminated, which is very simple and reliable, and will not affect the secondary use of the conductive pressure-sensitive tape 32, and is suitable for mass production; at the same time, the thickness of the IBC battery 31 has no effect on the use of the conductive pressure-sensitive tape 32 for connection, and is more suitable for the development of the IBC battery 31 towards thinning.

[0045] On the basis of any of the above embodiments, in one embodiment of the present application, the glass substrate 1 is ultra-white patterned glass, which has the characteristics of high light transmittance and low reflectivity, and can increase the amount of sunlight passing through the glass substrate 1, thereby increasing the amount of light absorbed by the battery layer and improving the photoelectric conversion efficiency of the IBC battery assembly. However, the present embodiment is not limited to this, and in another embodiment of the present application, the glass substrate 1 can also be tempered glass.

[0046] On the basis of any of the above embodiments, in one embodiment of the present application, the substrate 5 is a glass plate or a back plate. Specifically, when the IBC battery assembly is a single-glass assembly, the substrate 5 is a back plate, and when the IBC battery assembly is a double-glass assembly, the substrate 5 is a glass plate. Further, in this embodiment, the material of the back plate is not specifically limited and can be determined according to the circumstances. For example, the back plate can be a structural back plate such as TPT, TPE, KPE, etc.

[0047] This application also provides a method for manufacturing an IBC battery assembly, see Figure 7 , the method comprising:

[0048] Step S101: obtaining a plurality of prepared IBC batteries, substrates, a first adhesive film layer, a second adhesive film layer, and a glass substrate, wherein a first electrode and a second electrode spaced and arranged in parallel are distributed on the back of the IBC battery.

[0049] It should be noted that the IBC battery is manufactured by two different screen printing processes, thereby obtaining two types of IBC batteries in which the arrangement order of the first electrode and the second electrode is opposite. The specific manufacturing process is well known to those skilled in the art and will not be described in detail here.

[0050] Step S102: the IBC batteries having the first electrodes and the second electrodes arranged in opposite order are arranged alternately, and the first electrodes and the second electrodes of adjacent IBC batteries are connected by a conductive pressure-sensitive tape to obtain a battery layer.

[0051] Step S103: stacking the substrate, the first adhesive film layer, the battery cell layer, the second adhesive film layer, and the glass substrate in sequence, evacuating the layers using a laminator, and laminating the layers at a temperature of 140° C. to 150° C. to obtain an IBC battery assembly.

[0052] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0053] The above is a detailed introduction to the IBC battery assembly and its manufacturing method provided by the present application. This article uses specific examples to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and its core idea of ​​the present application. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. An IBC battery assembly, characterized in that: It includes a substrate, a first adhesive film layer, a battery layer, a second adhesive film layer, and a glass substrate stacked in sequence from bottom to top, wherein the battery layer includes a plurality of battery strings, each battery string includes a plurality of IBC batteries and a conductive pressure-sensitive adhesive tape for connecting adjacent IBC batteries; The conductive pressure-sensitive adhesive tape comprises a laminated base layer and a conductive pressure-sensitive adhesive layer, a first electrode and a second electrode are arranged in parallel at intervals on the back of the IBC battery, and the first electrode and the second electrode of adjacent IBC batteries are arranged in opposite order, and the conductive pressure-sensitive adhesive layer is connected to the first electrode and the second electrode of adjacent IBC batteries; The base layer is a PET film layer; the first electrode and the second electrode are both segmented electrodes, and the first electrode and the second electrode on the same IBC battery are aligned.

2. The IBC battery assembly according to claim 1, characterized in that: The conductive pressure-sensitive adhesive layer in the IBC battery assembly includes any one of a conductive filler, an adhesive, a rubber and a modified resin.

3. The IBC battery assembly according to claim 2, characterized in that: The conductive filler in the IBC battery assembly is a silver filler or a copper filler.

4. The IBC battery assembly according to claim 1, characterized in that: The first adhesive film layer and the second adhesive film layer are both EVA adhesive film layers or both POE adhesive film layers.

5. The IBC battery assembly according to claim 1, characterized in that: The glass substrate is ultra-white patterned glass.

6. The IBC battery assembly according to claim 1, characterized in that: The IBC battery is any one of a whole-piece IBC battery, a half-piece IBC battery, and a three-piece IBC battery.

7. The IBC battery assembly according to any one of claims 1 to 6, characterized in that: The substrate is a glass plate or a back plate.

8. A method for manufacturing an IBC battery assembly, characterized in that: include: A plurality of prepared IBC batteries, substrates, a first adhesive film layer, a second adhesive film layer, and a glass substrate are obtained, wherein a first electrode and a second electrode are spaced and arranged in parallel on the back of the IBC battery; the first electrode and the second electrode are both segmented electrodes, and the first electrode and the second electrode on the same IBC battery are aligned; The IBC batteries in which the first electrodes and the second electrodes are arranged in opposite order are arranged alternately, and the first electrodes and the second electrodes of adjacent IBC batteries are connected by a conductive pressure-sensitive tape to obtain a battery layer; the conductive pressure-sensitive tape comprises a laminated base layer and a conductive pressure-sensitive adhesive layer, and the base layer is a PET film layer; The substrate, the first adhesive film layer, the battery layer, the second adhesive film layer, and the glass substrate are stacked in sequence, and vacuumized using a laminator, and laminated at a temperature of 140° C. to 150° C. to obtain an IBC battery assembly.

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