Battery assembly and photovoltaic system

Abstract

The utility model provides a battery assembly and a photovoltaic system. The battery assembly comprises a battery string, a first welding strip, a second welding strip, a first bus bar and a first insulating strip. The plurality of battery pieces comprise first battery pieces; the first welding strip is arranged on the backlight surface of the first battery piece, and the first welding strip is conductively connected with the first battery piece; the second welding strip is arranged on the backlight surface of the first battery piece, and the second welding strip is conductively connected with the first battery piece; the first bus bar is arranged on the backlight surface of the first battery piece; the first insulating strip is arranged between the first bus bar and the first battery piece, a reflecting layer is arranged on the surface of the insulating strip, and the reflectivity of the reflecting layer is larger than or equal to 85%. According to the battery assembly provided by the utility model, the reflecting layer is arranged on the surface of the first insulating strip used for isolating the second welding strip from the first bus bar, and the reflectivity of the reflecting layer is greater than or equal to 85%, so that the light absorptivity of the battery piece in the battery assembly can be increased, and the photoelectric conversion efficiency of the battery assembly can be further improved.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic technology, and in particular to a battery module and a photovoltaic system. Background Technology

[0002] With increasingly strained global energy supplies, developing new energy sources has become a crucial energy strategy for many countries. Solar energy, due to its relative availability, has attracted growing attention, and the solar cell industry has developed rapidly in recent years, with cell modules finding increasingly wider applications.

[0003] However, as the application of battery modules becomes increasingly widespread, the demand for photoelectric conversion efficiency is also rising. Therefore, how to further improve the photoelectric conversion efficiency of battery modules has become an urgent problem to be solved. Utility Model Content

[0004] This invention provides a battery module and a photovoltaic system to solve the technical problem of how to improve the photoelectric conversion efficiency of the battery module.

[0005] This utility model is implemented as follows: It provides a battery module and a photovoltaic system. The battery module includes: a battery string comprising a plurality of battery cells arranged along a first direction, the plurality of battery cells including a first battery cell; a first solder strip and a second solder strip disposed on the back surface of the first battery cell, both the first solder strip and the second solder strip being electrically connected to the first battery cell; a first busbar disposed on the back surface of the first battery cell, the first busbar being electrically connected to the first solder strip; and a first insulating strip disposed between the first busbar and the first battery cell, both the first insulating strip and the first busbar extending along a second direction, the second direction intersecting the first direction. The first insulating strip is used to isolate the second solder strip and the first busbar. A reflective layer is provided on the surface of the insulating strip, the reflectivity of the reflective layer being greater than or equal to 85%.

[0006] Furthermore, the first insulating strip has a first positive surface and a second positive surface, the first positive surface and the second positive surface are disposed opposite to each other, the first positive surface is located on the side of the first insulating strip facing the first busbar, and the second positive surface is located on the side of the first insulating strip away from the first busbar; the reflective layer is disposed on the first positive surface and / or the second positive surface.

[0007] Furthermore, the first insulating strip has a first side surface and a second side surface arranged along a first direction, the first side surface and the second side surface being disposed opposite to each other; the reflective layer is disposed on the first side surface and / or the second side surface.

[0008] Furthermore, the first insulating strip is one of PET insulating strip, PI insulating strip, EVA insulating strip, and PVB insulating strip.

[0009] Furthermore, the reflective layer is a reflective layer applied to the first insulating strip by means of coating, bonding, and baking.

[0010] Furthermore, the reflective layer is one of a PTFE reflective layer or a TiO2 reflective layer.

[0011] Furthermore, the reflective layer partially covers the first positive surface.

[0012] Furthermore, the reflective layer completely covers the first positive surface.

[0013] Furthermore, the portion of the first positive surface that contacts the first busbar is not provided with the reflective layer, while the portion of the first positive surface that does not contact the first busbar is provided with the reflective layer.

[0014] This utility model embodiment also provides a photovoltaic system, which includes the battery module as described above.

[0015] In this embodiment of the present invention, the battery module has a reflective layer on the surface of the first insulating strip used to isolate the second solder strip and the first busbar. The reflectivity of the reflective layer is greater than or equal to 85%. When sunlight is incident on the battery module, the reflective layer can reflect the incident light that has not been absorbed by the battery cell back to the battery cell, thereby increasing the light absorption rate of the battery cell in the battery module, and thus improving the photoelectric conversion efficiency of the battery module and the overall efficiency of the battery module. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of a photovoltaic system module provided in one embodiment of the present invention;

[0018] Figure 2 This is a partial structural schematic diagram of a battery assembly provided in one embodiment of the present invention;

[0019] Figure 3 This is a cross-sectional schematic diagram of a portion of the structure of a battery assembly provided in one embodiment of the present invention;

[0020] Figure 4 This is a cross-sectional schematic diagram of a portion of the structure of a battery assembly provided in another embodiment of this utility model;

[0021] Figure 5 This is a schematic diagram of the structure of the first insulating strip in a battery assembly provided in one embodiment of the present invention;

[0022] Figure 6 This is a schematic diagram of a battery assembly provided in one embodiment of the present invention, in which a reflective layer is provided around the first insulating strip;

[0023] Figure 7 This is a schematic diagram of the structure of a battery assembly in which the reflective layer partially covers the first positive surface of the first insulating strip, according to an embodiment of the present invention.

[0024] Figure 8 This is a schematic diagram of the structure of a battery assembly provided in one embodiment of the present invention, in which the reflective layer completely covers the first positive surface of the first insulating strip.

[0025] Explanation of key component symbols: 1000, photovoltaic system; 100, battery module; 10, battery cell; 11, first battery cell; 20, first solder strip; 30, second solder strip; 40, first busbar; 50, first insulating strip; 60, reflective layer; 51, first front surface; 52, second front surface; 53, first side surface; 54, second side surface. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present utility model, and should not be construed as limiting the present utility model. Furthermore, it should be understood that the specific embodiments described herein are merely for explaining the present utility model and are not intended to limit the present utility model.

[0027] In the description of this utility model, it should be understood that the terms "length", "width", "upper", "lower", "top", "bottom", "lateral", "longitudinal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0028] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0029] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows for communication; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0030] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0031] The following disclosure provides numerous different embodiments or examples for implementing various structures of the present invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention; however, those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0032] Please see Figure 1The photovoltaic system 1000 in this embodiment of the present invention may include the battery module 100, which may include a plurality of battery cells 10. These battery cells 10 may be connected in series with solder strips to form a battery string. The battery strings in the battery module 100 may be connected in series, in parallel, or in a series-parallel combination to achieve current collection and output. For example, busbars may be used to connect the battery strings.

[0033] The accompanying drawings provided in this application are schematic diagrams, and some elements are not shown in the drawings. The purpose is to clearly describe the technical solution and highlight the key features of the utility model. It is not intended to limit the technical solution to exclude these unshown elements. That is to say, the drawings are merely examples and do not represent a limitation on the specific form of the battery module 100.

[0034] like Figures 2 to 7 As shown, the battery assembly 100 in this embodiment of the present invention includes: a battery string, a first solder ribbon 20, a second solder ribbon 30, a first busbar 40, and a first insulating strip 50. The battery string includes a plurality of battery cells 10 arranged along a first direction, and the plurality of battery cells 10 include a first battery cell 11; the first solder ribbon 20 is disposed on the back surface of the first battery cell 11 and is electrically connected to the first battery cell 11; the second solder ribbon 30 is disposed on the back surface of the first battery cell 11 and is electrically connected to the first battery cell 11; the first busbar 40 is disposed on the back surface of the first battery cell 11; the first insulating strip 50 is disposed between the first busbar 40 and the first battery cell 11, and both the first insulating strip 50 and the first busbar 40 extend along a second direction, which intersects with the first direction. The first insulating strip 50 is used to isolate the second solder ribbon 30 and the busbar, and a reflective layer 60 is provided on the surface of the insulating strip, the reflectivity of the reflective layer 60 being greater than or equal to 85%.

[0035] Thus, in this embodiment of the present invention, the battery module 100 has a reflective layer 60 on the surface of the first insulating strip 50 used to isolate the second solder strip 30 and the first busbar 40. The reflectivity of the reflective layer 60 is greater than or equal to 85%. When sunlight is incident on the battery module 100, the reflective layer 60 can reflect the incident light that has not been absorbed by the battery cell 10 back to the battery cell 10, thereby increasing the light absorption rate of the battery cell 10 in the battery module 100, and thus improving the photoelectric conversion efficiency of the battery module 100 and the overall efficiency of the battery module 100.

[0036] Furthermore, by providing a reflective layer 60 on the surface of the insulating strip in the battery assembly 100, the material used for the reflective layer 60 on the surface of the insulating strip is reduced because the insulating strip is small. Compared with the prior art of providing reflective materials at other locations in the battery assembly 100, the overall material used for the reflective layer 60 can be reduced, thereby reducing the cost of the battery assembly 100.

[0037] Specifically, in this embodiment of the invention, the test conditions for the reflectivity of the reflective layer 60 are as follows: The reflectivity is measured using a Perkin-Elmer Lambda 950 spectrophotometer in an environment of 25±2℃ and relative humidity ≤60%, according to GB / T 3979-2008 standard.

[0038] Specifically, the reflectivity of the reflective layer 60 is greater than or equal to 85%, and the reflectivity of the reflective layer 60 can be 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 99.5%.

[0039] It is understood that in a battery string, the battery string may include two battery cells 10 connected in series, three battery cells 10 connected in series, or a greater number of battery cells 10. The specific number of battery cells 10 to be connected in series can be determined according to the actual use, and this application does not impose any restrictions on this. In addition, the grid lines on the battery cells 10 are not shown in the accompanying drawings. The grid lines on the battery cells 10 can be arranged according to the actual situation. For example, it can be a battery cell 10 with a main grid or a battery cell 10 without a main grid.

[0040] like Figures 2 to 4 As shown, the first battery cell 11 is a battery cell 10 in a battery string that has a first busbar 40. In the first direction, the first battery cell 11 can be any one of the battery cells 10 in the battery string. For example, in the first direction, the first battery cell 11 can be the first battery cell 10, the second battery cell 10, the third battery cell 10, ..., the third to last battery cell 10, the second to last battery cell 10, the last battery cell 10, etc. in the battery string, etc., without limitation.

[0041] It should be noted that when the first battery cell 11 is located near the tail end of the battery string, the first busbar 40 can be used for series connection between adjacent battery strings in the second direction; when the first battery cell 11 is located near the head end of the battery string, the first busbar 40 can be used for parallel connection between adjacent battery strings in the first direction, and the first busbar 40 is equivalent to the intermediate busbar in the battery assembly 100.

[0042] In this embodiment, the first busbar 40 is disposed on the first battery cell 11, and the first busbar 40 and the first battery cell 11 are separated by a first insulating strip 50. On the one hand, the edge of the battery assembly 100 no longer needs to reserve space for placing the busbar, and the battery assembly 100 can reserve more space to install the battery cell 10, so that the effective light-receiving area of ​​the battery assembly 100 is larger and the conversion efficiency of the assembly is higher. On the other hand, when viewed from the light-receiving surface (or "front") of the battery cell 10, the first busbar 40 and the first insulating strip 50 can be blocked on the first battery cell 11, preventing the first busbar 40 and the first insulating strip 50 from being exposed, thereby improving the overall aesthetics of the battery assembly 100.

[0043] Secondly, as a possible scenario, placing the first busbar 40 on the side of the first battery cell would expose the first busbar 40 from the battery assembly 100, thus affecting the overall aesthetics of the battery assembly 100.

[0044] In this embodiment, the first busbar 40 is disposed on the backlight surface of the first battery cell 11, which allows the first solder ribbon 20 to fully adhere to and weld with the effective welding position of the first battery cell 11, thus avoiding insufficient welding between the first solder ribbon 20 and the first battery cell 11 due to the installation of the first busbar 40, which would affect the current collection.

[0045] It can be understood that the backlight side of the solar cell 10 refers to the side of the solar cell 10 that faces away from sunlight when the solar module 100 is naturally installed.

[0046] It is understood that the first solder ribbon 20 is located on the back surface of the first solar cell 11. This can mean that the entire first solder ribbon 20 is located on the back surface of the first solar cell 11, or it can mean that a portion of the first solder ribbon 20 is located on the back surface of the first solar cell 11; no limitation is made here.

[0047] It is understood that the second solder ribbon 30 is located on the back surface of the first solar cell 11. This can mean that the entire second solder ribbon 30 is located on the back surface of the first solar cell 11, or it can mean that a portion of the second solder ribbon 30 is located on the back surface of the first solar cell 11; there is no limitation here.

[0048] Furthermore, by setting both the first solder strip 20 and the second solder strip 30 to be located on the side of the first insulating strip 50 facing away from the first busbar 40, and by making openings in the first insulating strip 50 corresponding to the location of the first solder strip 20, the first solder strip 20 can be electrically connected to the first busbar 40 after being soldered to the first battery cell 11. This reduces the thickness of the battery assembly 100, thereby reducing the risk of microcracks and fragmentation of the battery cells 10 during the lamination of the battery assembly 100.

[0049] Alternatively, the second solder strips 30 can be positioned on the side of the first insulating strip 50 facing away from the first busbar 40, and the first solder strip 20 can be positioned on the side of the first busbar 40 facing away from the first insulating strip 50. This allows the first solder strip 20 to be directly conductively connected to the first busbar 40 after being soldered to the first battery cell 11. In this way, there is no need to drill holes in the insulating strip; during assembly, the first insulating strip 50 can simply be placed entirely on the first battery cell 11. This effectively reduces the precision requirements and manufacturing difficulty, avoids short circuits caused by positional misalignment during hole drilling of the insulating strip, and increases product yield.

[0050] In this embodiment of the application, the first direction is the horizontal direction, which is also the width direction of the battery cell 10, and the second direction is the vertical direction, which is also the length direction of the battery cell 10. The first direction and the second direction are perpendicular to each other.

[0051] In some embodiments, the battery string includes a plurality of battery cells 10 arranged along a first direction. Specifically, two adjacent battery cells 10 partially overlap. This eliminates the inter-cell spacing between adjacent battery cells 10 in the battery string, allowing more battery cells 10 to be placed in the battery string and improving the utilization efficiency of the battery string. Alternatively, two adjacent battery cells 10 have a spacing in the first direction. This ensures that adjacent battery cells 10 in the battery string have a certain inter-cell spacing, preventing mutual shading between adjacent battery cells 10, thereby improving the photoelectric conversion efficiency of the battery assembly 100.

[0052] The types of solar cells 10 in this embodiment include, but are not limited to, passivated emitter rear cell (PERC), tunnel oxide passivated contact (TOPCON), heterojunction with intrinsic thin-layer (HIT), back contact (BC), and perovskite solar cells (PSC). This embodiment does not specifically limit the type of solar cells 10 in the solar module 100.

[0053] like Figures 3 to 6As shown, it can be understood that the present application embodiment has a reflective layer 60 on the surface of the insulating strip. Through the reflective layer 60, incident light that is not absorbed by the battery cell 10 in the battery module 100 can be reflected back to the battery cell 10, thereby increasing the probability of secondary light absorption, reducing energy waste, and increasing the photoelectric conversion efficiency of the battery module 100, thus increasing the efficiency of the battery module 100. Furthermore, the reflective layer 60 can extend the propagation path of light inside the battery module 100 through multiple reflections, thereby improving the generation efficiency of photogenerated carriers in the battery cell 10, and further increasing the photoelectric conversion efficiency of the battery module 100, thus increasing the efficiency of the battery module 100.

[0054] Furthermore, the first insulating strip 50 itself is used to isolate the first busbar 40 from the second solder strip 30, avoiding the risk of short circuit. After providing a reflective layer 60 on the surface of the insulating strip, the insulation performance of the first insulating strip 50 can be further increased, thereby further reducing the risk of short circuit in the battery assembly 100.

[0055] In some embodiments, the reflective layer 60 can be integrated with the first insulating strip 50, thereby reducing the thickness of the battery assembly 100, reducing the packaging complexity of the battery assembly 100, and saving material costs.

[0056] In some embodiments, the reflective layer 60 and the first insulating strip 50 can be formed separately. In this way, the optical performance (such as reflectivity and weather resistance) of the reflective layer 60 and the electrical performance of the first insulating strip 50 can be tested independently, ensuring that both meet the standards before assembly, thereby improving the yield rate.

[0057] In one possible implementation, the first insulating strip 50 has a first front surface 51 and a second front surface 52, which are disposed opposite to each other. The first front surface 51 is located on the side of the first insulating strip 50 facing the first busbar 40, and the second front surface 52 is located on the side of the first insulating strip 50 away from the first busbar 40. The reflective layer 60 is disposed on the first front surface 51 and / or the second front surface 52. This can further increase the light absorption rate of the battery cells 10 in the battery assembly 100, thereby improving the photoelectric conversion efficiency of the battery assembly 100 and increasing the overall efficiency of the battery assembly 100.

[0058] Specifically, the first insulating strip 50 has a first positive surface 51 and a second positive surface 52 facing each other. The first positive surface 51 is the side of the first insulating strip 50 facing the first busbar 40, and the second positive surface 52 is the side of the first insulating strip 50 facing away from the first busbar 40.

[0059] like Figure 3 , Figure 5 and Figure 6As shown, the reflective layer 60 can be disposed on the first front surface 51 of the first insulating strip 50. The reflective layer 60 can be disposed adjacent to the first busbar 40. The reflective layer 60 can directly reflect transmitted light (such as infrared light) that is not absorbed by the battery cell 10 back to the battery cell 10, increasing the chance of secondary absorption and improving the photoelectric conversion efficiency and power generation efficiency of the battery module 100. At the same time, the reflective layer 60 being disposed on the first front surface 51 of the first insulating strip 50 allows the reflective layer 60 and the first busbar 40 to be on the same side, thereby allowing the user to simultaneously fix the reflective layer 60 and the first insulating layer when setting up the first busbar 40, thus reducing the assembly steps of the battery module 100 and improving the setting efficiency of the battery module 100.

[0060] like Figure 8 As shown, specifically, when the reflective layer 60 is disposed on the first front surface 51 of the first insulating strip 50, the reflective layer 60 completely covers the first front surface 51. In this way, the reflective layer 60, which completely covers the first front surface 51, can effectively reflect scattered light that is not absorbed by the battery cell 10, increase the reuse of light, and improve the photoelectric conversion efficiency of the battery assembly 100.

[0061] Specifically, when the reflective layer 60 is disposed on the first front surface 51 of the first insulating strip 50, the reflective layer 60 partially covers the first front surface 51. In this way, by setting the reflective layer 60 to partially cover the first front surface 51 of the first insulating strip 50, the photoelectric conversion efficiency of the battery assembly 100 can be effectively increased while the installation cost of the first insulating strip 50 can be reduced.

[0062] like Figure 7 As shown, further, regarding the arrangement where the first insulating strip 50 partially covers the first positive surface 51, the portion of the first positive surface 51 that contacts the busbar is not provided with the reflective layer 60, while the portion of the first positive surface 51 that does not contact the busbar is provided with the reflective layer 60.

[0063] Understandably, in actual configuration, the first insulating strip 50 is stacked on the first busbar 40, and the first front surface 51 is the surface of the first insulating strip 50 that contacts the first busbar 40, with the first front surface 51 facing the first busbar 40. Thus, the first busbar 40 will have direct contact with a portion of the first front surface 51. In this embodiment, a reflective layer 60 is selectively provided on the first front surface 51. The portion of the first front surface 51 that contacts the busbar does not have the reflective layer 60, while the portion that does not contact the busbar has the reflective layer 60. This avoids the reflective layer 60 being blocked by the first busbar 40, thus preventing it from failing to reflect light. This reduces resource waste of the reflective layer 60, thereby reducing the material cost of the reflective layer 60 and the cost of the battery assembly 100.

[0064] like Figure 3, Figure 5 and Figure 6 As shown, alternatively, the reflective layer 60 can be disposed on the second front surface 52 of the first insulating strip 50. The reflective layer 60 can be disposed close to the battery cell 10. The reflective layer 60 can directly reflect transmitted light (such as infrared light) that is not absorbed by the battery cell 10 back to the battery cell 10, increasing the chance of secondary absorption and improving the photoelectric conversion efficiency and power generation efficiency of the battery module 100. At the same time, the reflective layer 60 is disposed on the second front surface 52 of the first insulating strip 50, which allows the reflective layer 60 to be disposed at an interval from the first busbar 40, so that the reflective layer 60 and the first busbar 40 do not have direct contact. This reduces the risk of the reflective layer 60 being peeled off from the first busbar 40 due to the difference in the coefficient of thermal expansion, and can improve the placement stability of the reflective layer 60.

[0065] Alternatively, the reflective layer 60 can be simultaneously disposed on the first front surface 51 and the second front surface 52 of the first insulating strip 50. The reflective layer 60 can simultaneously increase the absorption of front light and back light by the battery assembly 100, thereby maximizing the light absorption efficiency in the battery assembly 100.

[0066] like Figure 3 , Figure 5 and Figure 6 As shown, in one possible implementation, the first insulating strip 50 has a first side surface 53 and a second side surface 54 arranged along a first direction, with the first side surface 53 and the second side surface 54 disposed opposite to each other; a reflective layer 60 is disposed on the first side surface 53 and / or the second side surface 54. This can further increase the light absorption rate of the battery cells 10 in the battery assembly 100, thereby improving the photoelectric conversion efficiency of the battery assembly 100 and increasing the overall efficiency of the battery assembly 100.

[0067] The reflective layer 60 can be disposed on the first side surface 53 of the first insulating strip 50. The reflective layer 60 can reflect the lateral incident light that is not absorbed by the solar cell 10 back to the solar cell 10, increasing the chance of secondary absorption and improving the photoelectric conversion efficiency and power generation efficiency of the solar cell module 100.

[0068] Alternatively, the reflective layer 60 can be disposed on the second side surface 54 of the first insulating strip 50. The reflective layer 60 can reflect the lateral incident light that is not absorbed by the solar cell 10 back to the solar cell 10, increasing the chance of secondary absorption and improving the photoelectric conversion efficiency and power generation efficiency of the solar cell module 100.

[0069] Alternatively, the reflective layer 60 can be simultaneously disposed on both the second side surface 54 and the second side surface 54 of the first insulating strip 50. The reflective layer 60 can maximize the absorption of lateral incident light by the battery assembly 100, thereby maximizing the light absorption efficiency in the battery assembly 100. Moreover, by disposing the reflective layer 60 on the side of the first insulating strip 50, the thickness of the battery assembly 100 can be increased without increasing the thickness of the reflective layer 60, and it will not hinder the installation of the solder ribbon.

[0070] like Figure 4 and Figure 6 As shown, in one possible implementation, the reflective layer 60 can be disposed on each surface of the first insulating strip 50. In this way, the reflective layer 60 can reflect light incident from various angles that is not absorbed by the solar cell 10 back to the solar cell 10, achieving a more comprehensive light reflection effect, thereby further improving the photoelectric conversion efficiency and overall power generation performance of the solar module 100. The full-coverage reflective design of the reflective layer 60 on each surface of the first insulating strip 50 can reflect scattered or leaked light that enters the solar module 100 from multiple directions but is not absorbed by the solar cell 10. Especially when there are tiny gaps between solar cells 10, the structure is complex, or there are multiple layers (such as solder ribbons, busbars, encapsulation films, etc.), the light path may undergo multiple refractions and scatterings. The full-surface reflective layer 60 on the first insulating strip 50 helps to return this light to the solar cell 10 as much as possible, improving the photon reuse rate in the solar cell 10 and increasing the number of photogenerated carriers in the solar cell 10.

[0071] In one possible implementation, the first insulating strip 50 is one of PET (polyethylene terephthalate) insulating strip, PI (polyimide) insulating strip, EVA (ethylene-vinyl acetate copolymer) insulating strip, or PVB (polyvinyl butyral) insulating strip. This increases the flexibility of the first insulating strip 50 in terms of application materials, allowing it to be used in different environments.

[0072] Specifically, the first insulating strip 50 can be a PET insulating strip. PET material has excellent mechanical properties, high strength, and good toughness, providing reliable adhesive strength and tear resistance. This makes the first insulating strip 50 less prone to deformation during lamination, helping to maintain the structural consistency of the battery assembly and further improving the stability and robustness of the first insulating strip 50. PET material also has good corrosion resistance, which can improve the stability of the first insulating strip 50.

[0073] Specifically, the first insulating strip 50 can be a PI insulating strip. PI material is resistant to high temperatures and possesses excellent mechanical properties, such as high strength, high modulus, and excellent toughness. Using a PI insulating strip as the first insulation further improves the installation stability of the first insulating strip 50. PI material also has excellent insulation properties and a low dielectric constant, is not easily corroded, can withstand high-energy radiation, and is suitable for use in harsh environments. Furthermore, it has a low coefficient of thermal expansion and small dimensional changes, which contribute to the good installation stability of the first insulating strip 50.

[0074] Specifically, the first insulating strip 50 can be an EVA insulating strip. EVA material has good flexibility, which can reduce hard contact between the first insulating strip 50 and the battery cell 10 and the first busbar 40, thus reducing wear and tear on the battery cell 10 and the first busbar 40. Furthermore, EVA material is relatively inexpensive, which can reduce the installation cost of the first insulating strip 50.

[0075] Specifically, the first insulating strip 50 can be a PVB insulating strip. PVB material has good impact resistance, which can reduce the risk of damage to the first insulating strip 50 during transportation or installation. At the same time, PVB material has good resistance to water vapor penetration, thereby improving the water vapor penetration resistance of the battery module 100.

[0076] In one possible implementation, the reflective layer 60 is one of a PTFE (polytetrafluoroethylene) reflective layer 60 and a TiO2 (titanium dioxide) reflective layer 60. This increases the flexibility of the reflective layer 60 in terms of application materials, allowing it to be used in different environments.

[0077] Specifically, the reflective layer 60 can be a PTFE reflective layer 60. PTFE material has good reflectivity, as well as good weather resistance, a wide temperature range, and resistance to acid, alkali, and salt spray corrosion. This improves the stability of the reflective layer 60.

[0078] Specifically, the reflective layer 60 can be a TiO2 reflective layer 60. TiO2 material possesses good reflectivity, excellent damp heat stability, and strong wear resistance, among other advantages. This improves the stability of the reflective layer 60.

[0079] In one possible implementation, the reflective layer 60 can be a reflective layer 60 disposed on the first insulating strip 50 by means of coating, bonding, and baking.

[0080] Specifically, the reflective layer 60 can be applied to the first insulating strip 50 via a coating process, achieving uniform coverage of the reflective layer 60 on the surface of the first insulating strip 50. This ensures consistent reflectivity throughout the reflective layer 60, avoiding "dark spots" or "hot spots" caused by localized fluctuations in optical performance, thereby guaranteeing the stability of the overall photoelectric conversion efficiency of the battery module 100. Simultaneously, the coating process allows for precise control of the reflective layer 60's thickness, ensuring optimal reflection without excessive thickness leading to material waste or increased thermal resistance, or insufficient reflection due to excessive thinness. This approach helps achieve the best balance between performance and cost. Finally, the uniform and controllable reflective layer 60 enhances the adhesion and weather resistance between the reflective layer 60 and the first insulating strip 50, reducing reliability risks associated with peeling or cracking during use.

[0081] Specifically, the reflective layer 60 can be attached to the first insulating strip 50 via a bonding process. This bonding process tightly bonds the pre-prepared reflective layer 60 to the first insulating strip 50, significantly improving the mechanical strength and integrity of the reflective layer 60. On one hand, under the action of hot pressing or pressure during the bonding process, the interface between the reflective layer 60 and the first insulating strip 50 is completely adhered, eliminating air gaps and micro-wrinkles, preventing delamination, bubbling, or edge lifting caused by vibration, thermal cycling, or humidity changes during use. On the other hand, it ensures that the reflective layer 60 will not peel or be damaged when subjected to external forces (such as laminator pressing, transportation vibration, or wind load impact), ensuring stable and reliable optical and electrical insulation performance of the reflective layer 60 and the first insulating strip 50 during long-term use. Furthermore, the bonding process is compatible with existing battery module 100 manufacturing processes, allowing the reflective layer 60 to be processed together with the encapsulant film in the battery module 100, facilitating mass production and process integration, and improving the production efficiency and product consistency of the battery module 100.

[0082] Specifically, the reflective layer 60 can be applied to the first insulating strip 50 via a baking process. The baking process can solidify the reflective layer 60 onto the first insulating strip 50, achieving molecular-level cross-linking and flow. This results in a tighter chemical and physical bond between the reflective layer 60 and the first insulating strip 50, significantly improving adhesion and preventing coating peeling during subsequent use. Consequently, this extends the lifespan of the battery module 100 and reduces its maintenance costs.

[0083] In one possible implementation, the reflective layer 60 is a black reflective layer 60. Thus, when the reflective layer 60 is applied to an all-black module, it can match the color of the battery module 100. The battery module 100 can be observed as an all-black module, and can be installed on commercial rooftops, ensuring the anti-glare effect of the battery module 100.

[0084] It is understood that the battery assembly 100 in such an embodiment may also include a frame, a backsheet, photovoltaic glass, and an encapsulating film. The encapsulating film may be filled in the front and back of the battery cells 10 and between the photovoltaic glass, adjacent battery cells 10, etc. As a filler, it may be a transparent colloid with good light transmittance and aging resistance. For example, the encapsulating film may be an EVA film or a POE film, and the specific choice can be made according to the actual situation, without limitation.

[0085] Photovoltaic glass can be applied to the encapsulating film on the front side of the solar cell 10. The photovoltaic glass can be ultra-clear glass, which has high light transmittance, high transparency, and superior physical, mechanical, and optical properties. For example, ultra-clear glass can achieve a light transmittance of over 92%, protecting the solar cell 10 while minimizing impact on its efficiency. Simultaneously, the encapsulating film bonds the photovoltaic glass and the solar cell 10 together, providing sealing, insulation, and waterproofing / moisture protection for the solar cell 10.

[0086] The backsheet can be attached to the adhesive film on the back of the solar cell 10. The backsheet provides protection and support for the solar cell 10, and has reliable insulation, water resistance, and aging resistance. Multiple options are available for the backsheet, typically tempered glass, acrylic glass, aluminum alloy TPT composite adhesive film, etc., and the specific choice depends on the specific circumstances and is not limited here. The backsheet, solar cell 10, adhesive film, and photovoltaic glass can be integrated into a frame. The frame serves as the main external support structure for the entire solar module 100, providing stable support and installation for the solar module 100. For example, the solar module 100 can be installed at the desired location via the frame.

[0087] In the description of this specification, the references to terms such as "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0088] Furthermore, the above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery assembly, characterized in that, include: A battery string, the battery string comprising a plurality of battery cells arranged along a first direction, the plurality of battery cells including a first battery cell; A first solder strip and a second solder strip are disposed on the back surface of the first battery cell, and both the first solder strip and the second solder strip are electrically connected to the first battery cell; A first busbar is disposed on the back surface of the first battery cell, and the first busbar is electrically connected to the first solder strip; A first insulating strip is disposed between the first busbar and the first battery cell. Both the first insulating strip and the first busbar extend along a second direction, which intersects with the first direction. The first insulating strip is used to isolate the second solder strip and the first busbar. A reflective layer is provided on the surface of the insulating strip, and the reflectivity of the reflective layer is greater than or equal to 85%.

2. The battery assembly according to claim 1, characterized in that, The first insulating strip has a first positive surface and a second positive surface, the first positive surface and the second positive surface are disposed opposite to each other, the first positive surface is located on the side of the first insulating strip facing the first busbar, and the second positive surface is located on the side of the first insulating strip away from the first busbar; The reflective layer is disposed on the first positive surface and / or the second positive surface.

3. The battery assembly according to claim 1, characterized in that, The first insulating strip has a first side surface and a second side surface arranged along a first direction, the first side surface and the second side surface being disposed opposite to each other; the reflective layer is disposed on the first side surface and / or the second side surface.

4. The battery assembly according to claim 1, characterized in that, The first insulating strip is one of PET insulating strip, PI insulating strip, EVA insulating strip, and PVB insulating strip.

5. The battery assembly according to claim 1, characterized in that, The reflective layer is applied to the first insulating strip by means of coating, bonding, and baking.

6. The battery assembly according to claim 1, characterized in that, The reflective layer is either a PTFE reflective layer or a TiO2 reflective layer.

7. The battery assembly according to claim 2, characterized in that, The reflective layer partially covers the first positive surface.

8. The battery assembly according to claim 2, characterized in that, The reflective layer completely covers the first positive surface.

9. The battery assembly according to claim 8, characterized in that, The portion of the first positive surface that contacts the first busbar is not provided with the reflective layer, while the portion of the first positive surface that does not contact the first busbar is provided with the reflective layer.

10. A photovoltaic system, characterized in that, Includes the battery assembly as described in any one of claims 1 to 9.

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