Battery assembly and preparation method thereof

Abstract

The invention discloses a battery assembly and a preparation method thereof, and the preparation method comprises the steps: manufacturing a front glue film and a back glue film, and enabling the front glue film and the back glue film to be respectively provided with a copper wire coated with a first specified material and a copper rod coated with a second specified material; connecting the copper wire and the copper rod which are positioned on the same adhesive film; placing a battery piece between the front adhesive film and the back adhesive film, and contacting the battery piece with the copper wire; and connecting the adjacent battery pieces in series through the contact of the copper rods on the front adhesive film and the back adhesive film. A silver material is not needed, so that the cost can be reduced, meanwhile, a welding strip is not needed for welding, the copper wire coated with the first specified material is used on the adhesive film, optical shielding can be effectively reduced, and the conversion efficiency of the battery is improved.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaic assembly manufacturing, and in particular to a battery assembly and a method for preparing the battery assembly. Background Art

[0002] At present, the cost of silver paste for metallization of photovoltaic cells is relatively high, and reducing the consumption of silver paste is one of the effective ways to reduce costs. At present, the silver-free metallization technology is mainly realized by copper paste and copper electroplating technology, but both have problems such as optical occlusion, and still need to use silver paste to print fine grid lines. Therefore, it is urgent to propose a new solution to solve the above problems. Summary of the invention

[0003] The purpose of the present invention is to provide a battery assembly and a method for preparing the battery assembly, which can reduce the cost and improve the battery conversion efficiency.

[0004] In order to solve the above technical problems, the present invention provides a battery assembly, comprising: a front adhesive film, a back adhesive film and a battery cell;

[0005] Copper wires coated with a first designated material and copper rods coated with a second designated material are provided on opposite sides of the front adhesive film and the back adhesive film, and the copper wires and copper rods located on the same adhesive film are connected;

[0006] The battery cell is located between the front adhesive film and the back adhesive film, and two opposite surfaces of the battery cell are in contact with the copper wire; adjacent battery cells are connected in series through the contact of the copper rods on the front adhesive film and the back adhesive film.

[0007] Furthermore, the number of copper wires on the front adhesive film is less than the number of copper wires on the back adhesive film.

[0008] Furthermore, the diameter of the copper wire on the front adhesive film is less than or equal to the diameter of the copper wire on the back adhesive film.

[0009] Further, the first designated material and the second designated material both include at least one of indium tin alloy, strontium vanadate, calcium vanadate or graphene.

[0010] Furthermore, the film thickness of the first designated material ranges from 0.5 μm to 10 μm; the film thickness of the second designated material ranges from 0.5 μm to 1000 μm.

[0011] Furthermore, the copper wire located on the same adhesive film is connected to the copper rod by welding, or the copper wire located on the same adhesive film is wound around the copper rod and then connected by welding.

[0012] Furthermore, the copper wire coated with the first designated material and the copper rod coated with the second designated material are both arranged on the surface of the front adhesive film and the surface of the back adhesive film, or the copper wire coated with the first designated material and the copper rod coated with the second designated material are both partially embedded in the front adhesive film and the back adhesive film.

[0013] In addition, the present invention also provides a method for preparing a battery assembly, and preparing the battery assembly as described above specifically includes the following steps:

[0014] Making a front adhesive film and a back adhesive film, wherein the front adhesive film and the back adhesive film both have copper wires coated with a first specified material and copper rods coated with a second specified material;

[0015] Connecting the copper wire and the copper rod located on the same adhesive film;

[0016] Placing the battery cell between the front adhesive film and the back adhesive film and contacting the battery cell with the copper wire; and

[0017] The adjacent battery cells are connected in series through the contact of the copper rods on the front adhesive film and the back adhesive film.

[0018] Furthermore, both the front film surface and the back film surface have copper wires coated with a first specified material and copper rods coated with a second specified material, which specifically includes: placing the copper wires into the first specified material in a molten state, and after cooling, the first specified material is coated on the copper wires.

[0019] Furthermore, both the surface of the front adhesive film and the surface of the back adhesive film have copper wires coated with a first specified material and copper rods coated with a second specified material, and specifically include: the copper wires coated with the first specified material and the copper rods coated with the second specified material are both arranged on the surface of the front adhesive film and the surface of the back adhesive film, or the copper wires coated with the first specified material and the copper rods coated with the second specified material are partially embedded in the front adhesive film and the back adhesive film.

[0020] Furthermore, placing the battery cell between the front film and the back film and contacting it with the copper wire specifically includes: firstly placing the side of the back film with the copper wire attached to it facing upward, placing one side of the battery cell above the copper wire of the back film, and then covering the other side of the front film with the copper wire attached to it; or, firstly placing the side of the front film with the copper wire attached to it facing upward, placing one side of the battery cell above the copper wire of the front film, and then covering the other side of the battery cell with the side of the back film with the copper wire attached to it.

[0021] Furthermore, a first predetermined distance is maintained between one side of the battery cell and the end of the copper wire of the front adhesive film, and a second predetermined distance is maintained between the other side of the battery cell and the end of the copper wire of the back adhesive film.

[0022] Furthermore, the first predetermined spacing and the second predetermined spacing are both in the range of 0.5 mm-1 mm.

[0023] Furthermore, the method further includes: fixing the assembled battery cells to obtain a battery assembly, which specifically includes:

[0024] Passing the assembled battery cell between two sets of heating rollers, the two sets of heating rollers simultaneously apply pressure to both sides of the assembled battery cell, so that the front adhesive film and the back adhesive film fix the battery cell inside, thereby obtaining a battery string;

[0025] The battery string is placed between two layers of glass for lamination to obtain the battery assembly.

[0026] Furthermore, the assembled battery cells are fixed to obtain a battery module, which specifically includes: based on the battery string, irradiating the copper wire and the copper rod with a laser to make the first designated material and the second designated material on the surface of the copper wire and the copper rod in a molten state so as to contact with the TCO of the battery cell.

[0027] Through the above technical solution, the present invention has the following beneficial effects:

[0028] By making a front film and a back film, both the front film and the back film have copper wires coated with a first specified material and copper rods coated with a second specified material; connecting the copper wires and the copper rods located on the same film; placing the battery cells between the front film and the back film and contacting with the copper wires; and connecting adjacent battery cells in series through the contact of the copper rods on the front film and the back film. The present invention does not need to use silver materials, so it can reduce costs. At the same time, it does not need to use welding strips, but uses copper wires coated with the first specified material on the film, which can effectively reduce optical occlusion, thereby improving battery conversion efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a flow chart of a method for preparing a battery assembly in one embodiment of the present invention;

[0030] Figure 2 is a cross-sectional view of a battery assembly according to an embodiment of the present invention;

[0031] Figure 3 is a top view of a battery assembly according to an embodiment of the present invention;

[0032] Figure 4 is a flow chart of a method for preparing a battery assembly in one embodiment of the present invention;

[0033] Figure 5 Schematic diagram of the structure of a battery assembly passing through a heating roller and a laser in one embodiment of the present invention.

[0034] In the figure, 1. front film; 2. back film; 3. copper wire; 4. copper rod; 5. battery cell; 6. heating roller; 7. conveying mechanism; 8. laser. DETAILED DESCRIPTION

[0035] A battery assembly and a method for preparing a battery assembly of the present invention will be described in more detail below in conjunction with the accompanying drawings, wherein preferred embodiments of the present invention are shown. It should be understood that those skilled in the art may modify the present invention described herein while still achieving the advantageous effects of the present invention. Therefore, the following description should be understood as being widely known to those skilled in the art and not as a limitation of the present invention.

[0036] The present invention is described in more detail in the following paragraphs by way of example with reference to the accompanying drawings. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the accompanying drawings are in very simplified form and are not in exact proportions, and are only used to facilitate and clearly assist in illustrating the purpose of the embodiments of the present invention.

[0037] like Figure 1-3 As shown, an embodiment of the present invention provides a method for preparing a battery assembly, which is used to prepare a battery assembly, and specifically includes the following steps:

[0038] S1, manufacturing a front adhesive film 1 and a back adhesive film 2, wherein the front adhesive film 1 and the back adhesive film 2 both have a copper wire 3 coated with a first specified material and a copper rod 4 coated with a second specified material;

[0039] S2, connecting the copper wire 3 and the copper rod 4 located on the same adhesive film; that is, connecting one end of the copper wire 3 on the same front adhesive film 1 to the copper rod 4; and connecting one end of the copper wire 3 on the same back adhesive film 2 to the copper rod 4;

[0040] S3, placing the battery cell 5 between the front adhesive film 1 and the back adhesive film 2, and contacting the battery cell 5 with the copper wire 3; and

[0041] S4, connecting the adjacent battery cells 5 in series through the contact of the copper rods 4 on the front adhesive film 1 and the back adhesive film 2.

[0042] In S1, the surface of the front adhesive film 1 and the surface of the back adhesive film 2 both have a copper wire 3 coated with a first designated material and a copper rod 4 coated with a second designated material, specifically comprising: placing the copper wire 3 in the first designated material in a molten state, and after cooling, the first designated material is coated on the copper wire 3. It is known to those skilled in the art that, under the same effect, the method of coating the surface of the copper rod 4 with the second designated material can also refer to the method of the copper wire 3 described above. For example, placing the copper rod 4 in the second designated material in a molten state, and after cooling, the second designated material is coated on the copper rod 4.

[0043] Further, in S1, the surface of the front adhesive film 1 and the surface of the back adhesive film 2 both have copper wires 3 coated with a first specified material and copper rods 4 coated with a second specified material, and specifically also includes: the copper wires 3 coated with the first specified material and the copper rods 4 coated with the second specified material are both arranged on the surface of the front adhesive film 1 and the surface of the back adhesive film 2, or the copper wires 3 coated with the first specified material and the copper rods 4 coated with the second specified material are both partially embedded in the front adhesive film 1 and the back adhesive film 2 (the exposed parts of the copper wires 3 and the copper rods 4 in the front adhesive film 1 and the back adhesive film 2 can realize subsequent steps).

[0044] Those skilled in the art may know that the copper wire 3 and the copper rod 4 may be flexibly arranged at different positions of the adhesive film, or partially embedded in adhesive films of different thicknesses, which may provide greater flexibility for later processing.

[0045] In S2, the copper wire 3 and the copper rod 4 located on the same adhesive film are connected, specifically including: directly welding the copper wire 3 and the copper rod 4 located on the same adhesive film to improve stability; or, on the premise of ensuring good conductivity of the copper wire 3 and the copper rod 4, the copper wire 3 located on the same adhesive film can also be wound around the copper rod 4 and then welded.

[0046] The copper wire 3 and the copper rod 4 after welding need to be properly cooled to prevent thermal stress from being generated.

[0047] In S3, the battery cell 5 is placed between the front adhesive film 1 and the back adhesive film 2 and in contact with the copper wire 3, specifically comprising: firstly facing the side of the back adhesive film 2 attached with the copper wire 3 upward, placing one side of the battery cell 5 above the copper wire 3 of the back adhesive film 2, and then covering the other side of the front adhesive film 1 with the copper wire 3 on the other side of the battery cell 5; or, firstly facing the side of the front adhesive film 1 attached with the copper wire 3 upward, placing one side of the battery cell 5 above the copper wire 3 of the front adhesive film 1, and then covering the other side of the battery cell 5 with the side of the back adhesive film 2 attached with the copper wire 3.

[0048] In this embodiment, one side of the battery cell 5 (i.e., the edge position of the battery cell 5) and the end of the copper wire 3 of the front adhesive film 1 (the end, i.e., the end of the copper wire 3 away from the connected copper rod 4) retain a first predetermined distance, and the other side of the battery cell 5 and the end of the copper wire 3 of the back adhesive film 2 (the end, i.e., the end of the copper wire 3 away from the connected copper rod 4) retain a second predetermined distance.

[0049] If one side of the battery cell 5 is aligned with the end of the copper wire 3 of the front film 1, one of the copper wires 3 in the front film 1 may contact with another copper wire 3, thereby causing a short circuit. Similarly, if the other side of the battery cell 5 is aligned with the end of the copper wire 3 of the back film 2, one of the copper wires 3 in the back film 2 may contact with another copper wire 3, thereby causing a short circuit.

[0050] Preferably, the first predetermined spacing and the second predetermined spacing are both in the range of 0.5 mm to 1 mm. By maintaining a certain spacing, the edge of the battery cell 5 can be prevented from directly contacting the copper wire 3, thereby avoiding the risk of short circuit and helping to improve the safety performance of the battery assembly.

[0051] In addition, if Figure 4 and Figure 5 As shown, this embodiment also includes the step: S5, processing the assembled battery cells 5 to obtain a battery assembly.

[0052] In this embodiment, the assembled battery cell 5 is processed to obtain a battery assembly, specifically including: S501, the assembled battery cell 5 passes between two groups of heating rollers 6, and the two groups of heating rollers 6 simultaneously apply pressure to both sides of the assembled battery cell 5, such as Figure 5 The direction indicated by the arrow pointing to the heating roller 6 is the direction of pressure application, and the applied pressure is F, so that the front adhesive film 1 and the back adhesive film 2 fix the battery cell 5 inside to obtain a battery string.

[0053] In this embodiment, the assembled battery cell 5 is fixed to obtain a battery assembly, which specifically includes: S502, based on the battery string, laser irradiation by laser 8 (such as Figure 5 In the figure, the arrow pointing from the laser 8 to the battery cell 5 indicates the laser irradiation direction) the copper wire 3 and the copper rod 4 are used to make the first designated material and the second designated material on the surface of the copper wire 3 and the copper rod 4 in a molten state so as to make good contact with the TCO (transparent conductive oxide film, Transparent Conductive0xide) of the battery cell 5.

[0054] In addition, this embodiment also includes S503: placing the cell string between two layers of glass for lamination to obtain the cell assembly. Lamination can provide physical protection for photovoltaic cells, prevent dust, moisture and other particles in the external environment from invading the cells, thereby avoiding damage to cell performance, and can also improve durability, efficiency, heat dissipation, electrical insulation, packaging stability and aesthetics.

[0055] Finally, the obtained battery assembly can be transported via the conveying mechanism 7 .

[0056] In addition, continue to refer to Figure 2 and Figure 3 This embodiment also provides a battery assembly, which is prepared using the battery assembly preparation method as described above, and includes: a front adhesive film 1, a back adhesive film 2 and a battery cell 5.

[0057] Specifically, a copper wire 3 coated with a first specified material and a copper rod 4 coated with a second specified material are provided on opposite sides of the front film 1 and the back film 2; the copper wire 3 and the copper rod 4 located on the same film are connected and located on the same horizontal plane; the battery cell 5 is located between the front film 1 and the back film 2, and two opposite surfaces of the battery cell 5 are in contact with the copper wire 3; adjacent battery cells 5 are connected in series through the contact between the copper rods 4 on the front film 1 and the back film 2.

[0058] Preferably, the first designated material and the second designated material both include indium tin alloy (i.e., ITO). Indium tin alloy has a high light transmittance, which can maximize the penetration of sunlight into the absorption layer of the photovoltaic cell, thereby improving the photoelectric conversion efficiency; and indium tin alloy has good electrical conductivity, which can effectively collect and transmit the current generated by the photovoltaic cell and reduce energy loss. Indium tin alloy can maintain the stability of its electrical and optical properties under various environmental conditions, which enables the battery assembly to maintain efficient operation for a long time.

[0059] In one embodiment, the number of copper wires 3 of the front adhesive film 1 and the number of copper wires 3 of the back adhesive film 2 are both set corresponding to the number of battery cells 5. The number of battery cells 5 is set according to actual needs.

[0060] In this embodiment, the number of copper wires 3 on the front adhesive film 1 is less than the number of copper wires 3 on the back adhesive film 2. The number of copper wires 3 on the front adhesive film 1 and the back adhesive film 2 can be set according to actual needs.

[0061] Among them, since the current generated by the photovoltaic cell under light needs to be effectively collected and transmitted, by placing more copper wires 3 on the back film 2, the current flowing from the back of the cell can be more effectively collected, thereby optimizing the current distribution of the entire solar panel. In addition, the copper wires 3 on the surface of the solar panel may cause light reflection and absorption, and reducing the number of copper wires 3 helps to improve the utilization rate of light by the solar panel.

[0062] Preferably, the diameter of the copper wire 3 on the front adhesive film 1 is less than or equal to the diameter of the copper wire 3 on the back adhesive film 2. The smaller diameter of the copper wire 3 on the front adhesive film 1 can further reduce the blocking of sunlight, thereby reducing the shadow effect and improving the photoelectric conversion efficiency of the photovoltaic cell. In addition, the smaller diameter of the copper wire 3 means that less material blocks the cell surface, so that more light can be absorbed by the cell, improving the light utilization rate.

[0063] In a specific example, by using copper wires 3 with larger diameters or a larger number on the back adhesive film 2, the current flowing out from the back of the battery can be more effectively collected and transmitted, thereby optimizing the current distribution of the entire battery panel.

[0064] In this embodiment, the copper wire 3 and the copper rod 4 located in the same adhesive film are connected by welding, or the copper wire 3 located in the same adhesive film is wound around the copper rod 4 and then connected by welding.

[0065] In this embodiment, the first designated material and the second designated material both include at least one of indium tin alloy, strontium vanadate, calcium vanadate or graphene. Preferably, the first designated material and the second designated material are both indium tin alloy (i.e., ITO). It is known to those skilled in the art that, while achieving the same effect, the first designated material and the second designated material can be selected according to actual needs, for example, strontium vanadate, calcium vanadate or graphene can be selected.

[0066] Preferably, the film thickness range of the first designated material and the second designated material is between 0.5μm and 10μm, for example, the film thickness of the first designated material and the second designated material can be 0.5μm, 1μm, 2μm, 4μm, 6μm, 8μm or 10μm, etc. Preferably, the film thickness range of the indium tin alloy is between 0.5μm and 10μm, for example, the film thickness of the indium tin alloy can be 0.5μm, 1μm, 2μm, 4μm, 6μm, 8μm or 10μm, etc. Within this thickness range, the indium tin alloy can maintain a high light transmittance to ensure the clarity and brightness of the display device. Indium tin alloy of appropriate thickness can provide good conductivity to ensure sensitivity and conversion efficiency of solar cells. Within the thickness range of this embodiment, the chemical stability and weather resistance of the indium tin alloy are good, which helps to extend the service life of electronic products.

[0067] Those skilled in the art will appreciate that, while achieving the same effect, the thickness of the indium tin alloy film can be set according to actual needs.

[0068] The film thickness of the second designated material may be greater than the film thickness of the first designated material. Specifically, the film thickness of the second designated material ranges from 10 μm to 1000 μm, for example, the film thickness of the second designated material may be 10 μm, 100 μm, 200 μm, 400 μm, 600 μm, 800 μm or 1000 μm, etc. Therefore, the film thickness of the second designated material may range from 0.5 μm to 1000 μm.

[0069] In addition, in one embodiment, the copper wire 3 coated with the first specified material and the copper rod 4 coated with the second specified material are both arranged on the surface of the front adhesive film 1 and the surface of the back adhesive film 2, or, the copper wire 3 coated with the first specified material and the copper rod 4 coated with the second specified material are both partially embedded in the front adhesive film 1 and the back adhesive film 2.

[0070] In summary, the battery assembly and the method for preparing the battery assembly proposed in the present invention have the following advantages:

[0071] By making a front film and a back film, both the front film and the back film have copper wires coated with a first specified material and copper rods coated with a second specified material; connecting the copper wires and the copper rods located on the same film; placing the battery cells between the front film and the back film and contacting with the copper wires; and connecting adjacent battery cells in series through the contact of the copper rods on the front film and the back film. The present invention does not need to use silver materials, so it can reduce costs. At the same time, it does not need to use welding strips, but uses copper wires coated with the first specified material on the film, which can effectively reduce optical occlusion, thereby improving battery conversion efficiency.

[0072] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A battery assembly, characterized in that: include: Front film, back film and battery cell; Copper wires coated with a first designated material and copper rods coated with a second designated material are provided on opposite sides of the front adhesive film and the back adhesive film, and the copper wires and copper rods located on the same adhesive film are connected; The battery cell is located between the front adhesive film and the back adhesive film, and two opposite surfaces of the battery cell are in contact with the copper wire; adjacent battery cells are connected in series through the contact of the copper rods on the front adhesive film and the back adhesive film.

2. The battery assembly according to claim 1, characterized in that The number of copper wires on the front adhesive film is less than the number of copper wires on the back adhesive film.

3. The battery assembly according to claim 1, characterized in that The diameter of the copper wire on the front adhesive film is less than or equal to the diameter of the copper wire on the back adhesive film.

4. The battery assembly according to claim 1, wherein: The first designated material and the second designated material both include at least one of indium tin alloy, strontium vanadate, calcium vanadate or graphene.

5. The battery assembly according to claim 1, characterized in that: The film thickness of the first designated material ranges from 0.5 μm to 10 μm; the film thickness of the second designated material ranges from 0.5 μm to 1000 μm.

6. The battery assembly according to claim 1, characterized in that: The copper wires located on the same adhesive film are connected to the copper rod by welding, or the copper wires located on the same adhesive film are wound around the copper rod and then connected by welding.

7. The battery assembly according to claim 1, characterized in that: The copper wire coated with the first designated material and the copper rod coated with the second designated material are both arranged on the surface of the front adhesive film and the surface of the back adhesive film, or the copper wire coated with the first designated material and the copper rod coated with the second designated material are both partially embedded in the front adhesive film and the back adhesive film.

8. A method for preparing a battery assembly, comprising preparing the battery assembly according to any one of claims 1 to 7, characterized in that: The details include: Making a front adhesive film and a back adhesive film, wherein the front adhesive film and the back adhesive film both have copper wires coated with a first specified material and copper rods coated with a second specified material; Connecting the copper wire and the copper rod located on the same adhesive film; Placing the battery cell between the front adhesive film and the back adhesive film and contacting the battery cell with the copper wire; and The adjacent battery cells are connected in series through the contact of the copper rods on the front adhesive film and the back adhesive film.

9. The method for preparing a battery assembly according to claim 8, characterized in that: The front film surface and the back film surface both have copper wires coated with a first designated material and copper rods coated with a second designated material, which specifically includes: placing the copper wires into the first designated material in a molten state, and after cooling, the first designated material is coated on the copper wires.

10. The method for preparing a battery assembly according to claim 9, characterized in that: The surface of the front film and the surface of the back film both have copper wires coated with a first specified material and copper rods coated with a second specified material, and specifically also include: the copper wires coated with the first specified material and the copper rods coated with the second specified material are both arranged on the surface of the front film and the surface of the back film, or the copper wires coated with the first specified material and the copper rods coated with the second specified material are both partially embedded in the front film and the back film.

11. The method for preparing a battery assembly according to claim 8, characterized in that: Placing the battery cell between the front film and the back film and contacting it with the copper wire specifically includes: firstly placing the side of the back film with the copper wire attached to it upward, placing one side of the battery cell above the copper wire of the back film, and then covering the other side of the battery cell with the side of the front film with the copper wire attached to it; or, firstly placing the side of the front film with the copper wire attached to it upward, placing one side of the battery cell above the copper wire of the front film, and then covering the other side of the battery cell with the side of the back film with the copper wire attached to it.

12. The method for preparing a battery assembly according to claim 11, characterized in that: A first predetermined distance is maintained between one side of the battery cell and the end of the copper wire of the front adhesive film, and a second predetermined distance is maintained between the other side of the battery cell and the end of the copper wire of the back adhesive film.

13. The method for preparing a battery assembly according to claim 12, characterized in that: The first predetermined distance and the second predetermined distance are both in the range of 0.5 mm-1 mm.

14. The method for preparing a battery assembly according to claim 8, characterized in that: Also includes: The assembled battery cells are fixed to obtain a battery assembly, which specifically includes: Passing the assembled battery cell between two sets of heating rollers, the two sets of heating rollers simultaneously apply pressure to both sides of the assembled battery cell, so that the front adhesive film and the back adhesive film fix the battery cell inside, thereby obtaining a battery string; The battery string is placed between two layers of glass for lamination to obtain the battery assembly.

15. The method for preparing a battery assembly according to claim 14, characterized in that: The method of fixing the assembled battery cells to obtain a battery assembly specifically includes: based on the battery string, irradiating the copper wire and the copper rod with a laser to make the first designated material and the second designated material on the surface of the copper wire and the copper rod in a molten state so as to contact the TCO of the battery cell.

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