Battery assembly and photovoltaic system

Abstract

The invention is suitable for the technical field of solar cells, and provides a cell module and a photovoltaic system. The battery assembly comprises a plurality of battery strings, a first adhesive film, a pre-fixing film and a reflective part, each battery string comprises a battery piece and a welding strip, the welding strip is connected with two adjacent battery pieces in the battery string, a gap is formed between two adjacent battery strings, the first adhesive film and the pre-fixing film are located on the two sides of the battery pieces respectively, and the welding strip and the battery pieces are fixed through the pre-fixing film; the reflecting part comprises a reflecting part and a connecting part, the reflecting part corresponds to the gap and is located on the side, away from the battery piece, of the pre-fixing film, and the connecting part protrudes from the reflecting part and penetrates through the gap to be connected with the first adhesive film. Therefore, the stability of fixing the reflective strips in the gaps is better, and the power generation efficiency of the battery assembly is improved.

Description

Technical Field

[0001] The present application belongs to the technical field of solar cells, and in particular to a battery assembly and a photovoltaic system. Background Art

[0002] Solar cell power generation is a sustainable source of clean energy. It uses the photovoltaic effect of semiconductor pn junction to convert sunlight into electrical energy. Multiple solar cells are connected and packaged to form a module. In the related art, reflective strips are usually set in the gaps between adjacent battery strings to reflect sunlight in the gaps to the solar cells, thereby improving the power generation efficiency of the module. However, the stability of the reflective strips fixed in the gaps is poor, resulting in poor power generation efficiency of the module.

[0003] Based on this, how to improve the stability of the reflective strip fixed in the gap has become an urgent problem to be solved. Summary of the invention

[0004] The present application provides a battery assembly and a photovoltaic system, aiming to solve the problem of how to improve the stability of fixing the reflective strip in the gap.

[0005] The battery assembly provided by the present application includes: a plurality of battery strings, a first adhesive film, a pre-fixed film and a reflector, wherein the battery string includes a battery cell and a welding strip, the welding strip connects two adjacent battery cells in the battery string, and a gap is formed between two adjacent battery strings, the first adhesive film and the pre-fixed film are respectively located on both sides of the battery cell, and the pre-fixed film fixes the welding strip to the battery cell;

[0006] The reflector comprises a reflective portion and a connecting portion. The reflective portion is arranged corresponding to the gap and is located on a side of the pre-fixed film away from the battery sheet. The connecting portion protrudes from the reflective portion and passes through the gap to connect with the first adhesive film.

[0007] Specifically, the pre-fixed film is made of a first material, the connecting portion is made of a second material, and in the gap, the content of the second material is greater than that of the first material.

[0008] Specifically, the ratio of the content of the second material to the content of the first material is greater than or equal to 5.

[0009] Specifically, the first material includes POE, and the second material includes EVA.

[0010] Specifically, in the thickness direction of the battery assembly, the thickness of the connecting portion is smaller than the thickness of the battery cell;

[0011] Alternatively, the thickness of the connecting portion is greater than the thickness of the battery cell.

[0012] Specifically, the reflective part includes a first adhesive layer, a reflective layer, and a second adhesive layer that are stacked in sequence, and the connecting part protrudes from the first adhesive layer.

[0013] Specifically, the thickness of the reflective layer is 10 μm - 300 μm.

[0014] Specifically, the width of the reflective layer is 0.5 mm - 10 mm.

[0015] Specifically, the reflective layer includes at least one of aluminum, silver, chromium, silicon dioxide, and titanium dioxide.

[0016] The photovoltaic system provided in this application includes the battery assembly of any one of the above.

[0017] In the battery assembly and the photovoltaic system of the embodiments of this application, since the connecting part of the reflective member passes through the gap to connect the first adhesive film, the position of the connecting part can be restricted by using two adjacent battery strings while fixing the reflective member to the first adhesive film, thereby restricting the position of the reflective member, and the risk of displacement of the reflective member caused by the melting and flowing of the adhesive film during lamination can be reduced. At the same time, since the pre-fixing film is located on one side of the reflective part, the reflective part can be further fixed while fixing the welding tape to the battery cell. In this way, the stability of the reflective strip fixed in the gap is better, which is beneficial to improving the power generation efficiency of the battery assembly. Description of the Drawings

[0018] Figure 1 is a schematic structural diagram of a battery assembly according to an embodiment of this application;

[0019] Figure 2 is a schematic structural diagram of a battery assembly according to an embodiment of this application;

[0020] Figure 3 is a schematic structural diagram of a reflective member of a battery assembly according to an embodiment of this application;

[0021] Main Element Symbol Description:

[0022] Battery assembly 100, battery string 10, battery cell 11, welding tape 12, gap 101, first adhesive film 20, pre-fixing film 30, reflective member 40, reflective part 41, first adhesive layer 411, reflective layer 412, second adhesive layer 413, connecting part 42, second adhesive film 50, front plate 61, back plate 62. Detailed Embodiments

[0023] To make the objectives, technical solutions and advantages of the present application more clear and understandable, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present application and should not be construed as a limitation to the present application. In addition, it should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0024] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "left", "right", "horizontal", "top", "bottom", etc. is based on the orientation or positional relationship shown in the accompanying drawings. These are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application.

[0025] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present application, "a plurality of" means two or more unless otherwise specifically defined.

[0026] In the description of the present application, it should be noted that unless otherwise clearly specified and defined, the terms "mounted", "connected" and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection or an integral connection; it may be a mechanical connection, an electrical connection or a connection that allows mutual communication; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0027] In the present application, unless otherwise clearly specified and defined, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features therebetween. Moreover, the first feature being "above", "over" and "on" the second feature includes that the first feature is directly above and obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "under" the second feature includes that the first feature is directly below and obliquely below the second feature, or simply means that the horizontal height of the first feature is lower than that of the second feature.

[0028] The following disclosure provides many different embodiments or examples for implementing different structures of the present application. To simplify the disclosure of the present application, the components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the present application. In addition, the present application may repeat reference numerals and / or reference letters in different examples. This repetition is for the purpose of simplification and clarity and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present application provides examples of various specific processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use scenarios of other materials.

[0029] Please refer to Figure 1 、 Figure 2 and Figure 3 As shown in

[0030] FIGs.

[0031] The battery assembly 100 of the embodiment of the present application includes: a plurality of battery strings 10, a first adhesive film 20, a pre-fixing film 30, and a light-reflecting member 40. The battery string 10 includes battery cells 11 and solder tapes 12. The solder tapes 12 connect two adjacent battery cells 11 in the battery string 10. A gap 101 is formed between two adjacent battery strings 10. The first adhesive film 20 and the pre-fixing film 30 are respectively located on both sides of the battery cell 11. The pre-fixing film 30 fixes the solder tape 12 to the battery cell 11.

[0032] The light-reflecting member 40 includes a light-reflecting portion 41 and a connecting portion 42. The light-reflecting portion 41 is correspondingly arranged with the gap 101 and is located on the side of the pre-fixing film 30 away from the battery cell 11. The connecting portion 42 protrudes from the light-reflecting portion 41 and passes through the gap 101 to connect the first adhesive film 20.

[0033] Specifically, the front plate 61 can be a glass front plate 61, a polymer front plate 61, etc. For example, the front plate 61 is ultra-white glass. In this way, the front plate 61 has a high light transmittance, high transparency, and excellent physical, mechanical, and optical properties. The light transmittance can reach more than 92%, and the solar cell can be protected without significantly affecting the efficiency of the solar cell as much as possible.

[0034] Specifically, the back plate 62 can protect and support the battery string 10, and has reliable insulation, water resistance, and aging resistance. The back plate 62 can be tempered glass, plexiglass, aluminum alloy TPT composite film, etc., and is not limited here.

[0035] Specifically, the first adhesive film 20 includes at least one of POE, EVA, EPE, EP, PE, and PVB. For example, the first adhesive film 20 includes POE. Another example is that the first adhesive film 20 includes POE and EVA. Still another example is that the first adhesive film 20 includes POE, EVA, EPE, EP, PE, and PVB. Similarly, the second adhesive film 50 includes at least one of POE, EVA, EPE, EP, PE, and PVB. For example, the second adhesive film 50 includes POE. Another example is that the second adhesive film 50 includes POE and EVA. Still another example is that the second adhesive film 50 includes POE, EVA, EPE, EP, PE, and PVB. It can be understood that the first adhesive film 20 and the second adhesive film 50 can bond the various components of the battery module 100 together and perform sealing insulation, waterproofing, and moisture-proofing.

[0036] Specifically, the pre-fixing film 30 includes at least one of PVB, EVA, EPE, EP, and POE. For example, the pre-fixing film 30 includes PVB. Another example is that the pre-fixing film 30 includes PVB and EVA. Still another example is that the pre-fixing film 30 includes PVB, EVA, EPE, EP, and POE.

[0037] Specifically, the whole composed of the front plate 61, the first adhesive film 20, the battery string 10, the pre-fixing film 30, the second adhesive film 50, and the back plate 62 can be arranged in a frame. The frame can be the main external support structure of the entire battery module 100 and can provide stable support and installation for the battery module 100. For example, the battery module 100 can be installed at the required installation position through the frame.

[0038] Specifically, the number of battery strings 10 can be 2, 3, 4, or other numbers, which are not limited here.

[0039] Specifically, the battery string 10 includes battery cells 11 and welding tapes 12, and the welding tapes 12 connect two adjacent battery cells 11 in the battery string 10. Further, the welding tape 12 connects the positive grid line of one battery cell 11 and the negative electrode of another battery cell 11. It can be understood that in one battery cell 11, the welding tape 12 may include a first welding tape and a second welding tape. The first welding tape connects the positive grid line of the battery cell 11, and the second welding tape connects the negative grid line of the battery cell 11. For example, in Figure 1 and Figure 2 , in one battery cell 11, the two types of welding tapes 12 are arranged alternately at intervals, and red and black respectively represent the two types of welding tapes 12 in one battery cell 11.

[0040] Specifically, a gap 101 is formed between two adjacent battery strings 10. In this way, the risk of fragmentation of the battery string 10 during lamination can be reduced. The width of the gap 101, that is, the distance between two adjacent battery strings 10, can be always the same or can vary, which is not limited herein.

[0041] Specifically, the first adhesive film 20 and the pre-fixing film 30 are respectively located on both sides of the battery cell 11. That is, the pre-fixing film 30 is located on the side of the battery cell 11 facing the back plate 62, and the first adhesive film 20 is located on the side of the battery cell 11 facing the front plate 61.

[0042] Specifically, the pre-fixing film 30 can fix the relative positions of the welding tape 12 and the battery cell 11, reducing the risk that the welding tape 12 deviates from the grid line of the battery cell 11 during the manufacturing process of the battery module 100. During the lamination process, the pre-fixing film 30 melts, can fill the gap between the welding tape 12 and the battery cell 11, and prevent the first adhesive film 20 or the second adhesive film 50 from filling into the gap between the welding tape 12 and the battery cell 11. The melted pre-fixing film 30 can also fill into the gap between the welding tape 12 and the battery cell 11 together with the adhesive film. The melted pre-fixing film 30 can fill into the gap 101 between two adjacent battery strings 10, or can be located outside the gap 101 between two adjacent battery strings 10. The position of the melted pre-fixing film 30 is not limited herein.

[0043] Specifically, the light reflector 40 includes a light reflecting portion 41 and a connecting portion 42 protruding from the light reflecting portion 41. The light reflecting portion 41 is correspondingly arranged with the gap 101, which means that along the thickness direction of the battery cell 11, at least part of the positive projection of the light reflecting portion 41 and the gap 101 on the same plane overlap. For example, the light reflecting portion 41 covers and extends beyond the gap 101; another example is that the light reflecting portion 41 covers a part of the gap 101; still another example is that in the thickness direction of the battery cell 11, the light reflecting portion 41 is aligned with the edge of the gap 101.

[0044] Specifically, the light-reflecting portion 41 is located on the side of the pre-fixing film 30 away from the battery cell 11. In this way, the light-reflecting portion 41 can reflect the light passing through the gap 101, so that the light is incident on the battery cell 11 again, thereby reducing the loss of light. Moreover, the pre-fixing film 30 can be used to fix the light-reflecting portion 41.

[0045] Specifically, the shape of the light-reflecting portion 41 can be cylindrical, prismatic, frustum-shaped, pyramid-shaped or other shapes. It is not limited here.

[0046] Specifically, the connecting portion 42 protrudes from the light-reflecting portion 41 and passes through the gap 101 to connect the first adhesive film 20. In this way, while fixing the light-reflecting member 40 to the first adhesive film 20, the position of the connecting portion 42 can be restricted by two adjacent battery strings 10, so as to restrict the position of the light-reflecting member 40, and the risk of displacement of the light-reflecting member 40 caused by the melting and flowing of the adhesive film during lamination can be reduced.

[0047] Specifically, the shape of the connecting portion 42 can be cylindrical, prismatic, frustum-shaped, pyramid-shaped or other shapes. It is not limited here.

[0048] Please refer to Figure 1 、 Figure 2 and Figure 3 , in some embodiments, the pre-fixing film 30 is made of a first material, the connecting portion 42 is made of a second material, and in the gap 101, the content of the second material is greater than that of the first material.

[0049] In this way, there are the materials of the connecting portion 42 and the pre-fixing film 30 in the gap 101, and the content of the material of the connecting portion 42 is larger, so that the distribution range of the connecting portion 42 in the gap 101 is larger and the connection range with the first adhesive film 20 is larger, thereby making the connection between the connecting portion 42 and the first adhesive film 20 more stable, and further making the stability of the light-reflecting strip fixed in the gap 101 better, which is beneficial to improving the power generation efficiency of the battery module 100.

[0050] Specifically, the first material and the second material are different materials.

[0051] Furthermore, the first material includes at least one of PVB, EVA, EPE, EP and POE. The second material includes at least one of PVB, EVA, EPE, EP and POE. For example, the first material includes PVB and the second material includes EVA. Another example is that the first material includes PVB and EVA, and the second material includes EP and POE.

[0052] Specifically, "the content of the second material is greater than that of the first material" means that in the filler in the gap 101, the content of the second material is greater than that of the first material. It can be understood that all the fillers can be

[0053] InFigure 1 and Figure 2 in the example of Figure 1 is Figure 2 a sectional view formed by slicing along the arrangement direction of the battery string 10 (i.e., the horizontal direction in Figure 2 ). It can be understood that by slicing along the arrangement direction of the battery string 10 (i.e., the horizontal direction in Figure 2 ), and taking a preset length along the extension direction of the battery string 10 (i.e., the vertical direction in Figure 2 ), a sampling block of the filler in the gap 101 can be obtained. The edge of the sampling block along the thickness direction of the battery string 10 is flush with the edge of the battery cell 11 in the thickness direction, as shown by the dashed line in Figure 1 . The edge of the sampling block along the arrangement direction of the battery string 10 corresponds to the side edge of the battery cell 11. The preset length is 60μm - 100μm. For example, it can be 60μm, 62μm, 65μm, 68μm, 70μm, 75μm, 78μm, 80μm, 85μm, 88μm, 90μm, 95μm, 98μm, 100μm.

[0054] In some embodiments, the ratio of the content of the second material to the content of the first material is greater than or equal to 5. For example, it can be 5, 6, 7, 8, 9, 10 or other values.

[0055] In this way, making the ratio of the content of the second material to the content of the first material within a suitable range can avoid the situation where the distribution range of the connecting portion 42 in the gap 101 is small and the connection range with the first adhesive film 20 is small due to a small ratio, thereby making the connection between the connecting portion 42 and the first adhesive film 20 more stable, and further making the stability of the reflective strip fixed in the gap 101 better.

[0056] In some embodiments, the first material is POE and the second material is EVA. In this way, the fluidity of the material of the pre - fixing film 30 is lower, and the effect of fixing the welding tape 12 to the battery cell 11 is better.

[0057] In some embodiments, the material of the connecting portion 42 is the same as the material of the first adhesive film 20. In this way, the connection between the connecting portion 42 and the first adhesive film 20 is more stable, and further the stability of the reflective strip fixed in the gap 101 is better.

[0058] In some embodiments, in the thickness direction of the battery module 100, the thickness of the connecting portion 42 is less than the thickness of the battery cell 11. In this way, when laminating, the first adhesive film 20 melts and enters the gap 101 and contacts the connecting portion 42, which can save the cost of the connecting portion 42.

[0059] In some embodiments, the thickness of the connecting portion 42 is greater than the thickness of the battery cell 11. In this way, it is ensured that the connecting portion 42 is in contact with the first adhesive film 20. Moreover, when laminating, the connecting portion 42 melts and enters the gap 101, and the material content of the connecting portion 42 in the gap 101 is more, and the connection stability with the first adhesive film 20 is better.

[0060] In some embodiments, the ratio of the thickness of the connecting portion 42 to the thickness of the battery cell 11 may be 0.5 - 1.5. For example, it may be 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5. In this way, the ratio of the thickness of the connecting portion 42 to the thickness of the battery cell 11 is within a suitable range, which can avoid the difficulty of the connecting portion 42 contacting the first adhesive film 20 and the poor connection stability caused by too small a ratio, and can also avoid the connecting portion 42 protruding too much from the battery cell 11 and interfering with the setting of the first adhesive film 20 when the connecting portion 42 is disposed in the gap 101 due to too large a ratio.

[0061] Please refer to Figure 1 、 Figure 2 and Figure 3 In some embodiments, the light reflecting portion 41 includes a first adhesive layer 411, a light reflecting layer 412, and a second adhesive layer 413 that are stacked in sequence, and the connecting portion 42 protrudes from the first adhesive layer 411.

[0062] In this way, the light incident on the gap 101 can be reflected to the battery cell 11 by the light reflecting layer 412, and the fixing of the connecting portion 42 can be made more stable by the first adhesive layer 411 and the second adhesive layer 413.

[0063] Specifically, the connecting portion 42, the first adhesive layer 411, and the second adhesive layer 413 may all have the same material, may all have different materials, or two of the connecting portion 42, the first adhesive layer 411, and the second adhesive layer 413 may have the same material and the remaining one may have a different material. It is not limited here.

[0064] In this embodiment, the connecting portion 42, the first adhesive layer 411, and the second adhesive layer 413 may all have the same material. In this way, the structure of the light reflecting member 40 is simpler and the cost is lower.

[0065] Specifically, the first adhesive layer 411 may cover a partial area or the entire area of one side of the light reflecting layer 412. The second adhesive layer 413 may cover a partial area or the entire area of the other side of the light reflecting layer 412.

[0066] Specifically, a third adhesive layer may also be provided on the side surface of the light reflecting layer 412. In this way, the side surface of the light reflecting layer 412 can also be connected through the adhesive layer, and the fixing stability is higher.

[0067] Please refer to Figure 3, in some embodiments, the thickness d1 of the reflective layer 412 is 10 μm - 300 μm. For example, it is 10 μm, 12 μm, 20 μm, 50 μm, 80 μm, 100 μm, 120 μm, 150 μm, 180 μm, 200 μm, 220 μm, 250 μm, 280 μm, 300 μm.

[0068] In this way, the thickness d1 of the reflective layer 412 is within a suitable range, which can avoid poor reflective effect or insufficient strength and easy damage caused by too small thickness d1 of the reflective layer 412, and can also avoid high cost caused by too large thickness d1 of the reflective layer 412.

[0069] Preferably, the thickness d1 of the reflective layer 412 is 25 μm - 200 μm. For example, it is 25 μm, 28 μm, 30 μm, 50 μm, 80 μm, 100 μm, 120 μm, 150 μm, 180 μm, 200 μm. In this way, the thickness d1 of the reflective layer 412 is further optimized, taking into account the reflective effect and cost, and the overall effect is better.

[0070] Please refer to Figure 3 , in some embodiments, the thickness d2 of the first adhesive layer 411 is 10 μm - 600 μm. For example, it is 10 μm, 12 μm, 20 μm, 80 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 580 μm, 600 μm.

[0071] In this way, the thickness d2 of the first adhesive layer 411 is within a suitable range, which can avoid poor connection effect with the pre - fixing film 30 or the battery cell 11 caused by too small thickness d2 of the first adhesive layer 411, and can also avoid high cost caused by too large thickness d2 of the first adhesive layer 411.

[0072] Preferably, the thickness d2 of the first adhesive layer 411 is 25 μm - 500 μm. For example, it is 25 μm, 30 μm, 80 μm, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm. In this way, the thickness d2 of the first adhesive layer 411 is further optimized, taking into account the connection effect and cost, and the overall effect is better.

[0073] Please refer to Figure 3 , in some embodiments, the thickness d3 of the second adhesive layer 413 is 10 μm - 600 μm. For example, it is 10 μm, 12 μm, 20 μm, 80 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 580 μm, 600 μm.

[0074] In this way, the thickness d3 of the second adhesive layer 413 is within a suitable range, which can avoid poor connection effects with the pre-fixed film 30 or the battery cell 11 caused by too small a thickness d3 of the second adhesive layer 413, and can also avoid high costs caused by too large a thickness d3 of the second adhesive layer 413.

[0075] Preferably, the thickness d3 of the second adhesive layer 413 is 25 μm - 500 μm. For example, it is 25 μm, 30 μm, 80 μm, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm. In this way, the thickness d3 of the second adhesive layer 413 is further optimized, taking into account both the connection effect and the cost, and the overall effect is better.

[0076] Please refer to Figure 3 , in some embodiments, the thickness d4 of the connecting portion 42 is 150 μm - 2000 μm. For example, it is 150 μm, 180 μm, 200 μm, 500 μm, 800 μm, 1000 μm, 1200 μm, 1500 μm, 1800 μm, 2000 μm.

[0077] In this way, the thickness d4 of the connecting portion 42 is within a suitable range, which can avoid poor connection stability with the first adhesive layer 411 or even inability to connect to the first adhesive layer 411 caused by too small a thickness d4 of the connecting portion 42, and can also avoid large interference with the first adhesive layer 411 or high costs caused by too large a thickness d4 of the connecting portion 42.

[0078] Preferably, the thickness d4 of the connecting portion 42 is 150 μm - 1000 μm. For example, it is 150 μm, 180 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm, 1000 μm. In this way, the thickness d4 of the connecting portion 42 is further optimized, taking into account both the connection effect and the cost, and the overall effect is better.

[0079] Please refer to Figure 3 , in some embodiments, the width w1 of the reflective layer 412 is 0.5 mm - 10 mm. For example, it is 0.5 mm, 0.8 mm, 1 mm, 3 mm, 5 mm, 7 mm, 8 mm, 10 mm.

[0080] In this way, the width w1 of the reflective layer 412 is within a suitable range, which can avoid the inability to cover the gap 101 and the loss of some light passing through the gap 101 without being contacted by the reflective layer 412 caused by too small a width w1 of the reflective layer 412, and can also avoid high costs caused by too large a width w1 of the reflective layer 412.

[0081] Further, the width w1 of the reflective layer 412 is 1 mm - 8 mm. For example, it is 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm. In this way, the width w1 of the reflective layer 412 is further optimized, taking into account the reflective effect and cost, and the overall effect is better. Preferably, the width w1 of the reflective layer 412 is 4.5 mm - 5 mm. For example, it is 4.5 mm, 4.6 mm, 4.7 mm, 4.8 mm, 4.9 mm, 5 mm.

[0082] Please refer to Figure 3 , in some embodiments, the widths of the first adhesive layer 411 and the second adhesive layer 413 may be the same as the width w1 of the reflective layer 412, or may be different from the width w1 of the reflective layer 412.

[0083] Please refer to Figure 3 , in some embodiments, the width w2 of the connecting portion 42 is less than or equal to 2 mm. For example, it is 2 mm, 1.8 mm, 1.5 mm, 1.2 mm, 1 mm, 0.8 mm, 0.5 mm, 0.2 mm, 0.1 mm.

[0084] In this way, the width w2 of the connecting portion 42 is within a suitable range, which can avoid the unstable connection with the first adhesive film 20 caused by too small a width, and can also avoid the difficulty of being placed in the gap 101 or the high cost caused by too large a width.

[0085] Preferably, the width w2 of the connecting portion 42 is less than or equal to 1 mm. For example, it is 1 mm, 0.9 mm, 0.8 mm, 0.7 mm, 0.6 mm, 0.5 mm, 0.4 mm, 0.3 mm, 0.2 mm, 0.1 mm. In this way, the width w2 of the connecting portion 42 is further optimized, taking into account the connection effect, adaptation to the gap 101 and cost, and the overall effect is better.

[0086] In some embodiments, the reflective layer 412 includes at least one of aluminum, silver, chromium, silicon dioxide, and titanium dioxide.

[0087] In this way, multiple forms of the reflective layer 412 are provided, making the reflective layer 412 more flexible and adaptable to more production scenarios.

[0088] For example, the reflective layer 412 includes aluminum; another example is that the reflective layer 412 includes aluminum and chromium; still another example is that the reflective layer 412 includes aluminum, silver, chromium, silicon dioxide, and titanium dioxide. This is only an example here and does not represent a limitation on the specific form of the reflective layer 412.

[0089] The photovoltaic system of the embodiment of the present application includes the above-mentioned battery module 100.

[0090] In the photovoltaic system according to the embodiment of the present application, in the battery module 100, since the connecting portion 42 of the light reflecting member 40 passes through the gap 101 to connect the first adhesive film 20, the position of the connecting portion 42 can be restricted by two adjacent battery strings 10 while the light reflecting member 40 is fixed to the first adhesive film 20, thereby restricting the position of the light reflecting member 40, and the risk of displacement of the light reflecting member 40 caused by the melting and flowing of the adhesive film during lamination can be reduced. At the same time, since the pre-fixing film 30 is located on one side of the light reflecting portion 41, the light reflecting portion 41 can be further fixed while the welding tape 12 is fixed to the battery cell 11. In this way, the stability of the light reflecting strip fixed in the gap 101 is better, which is beneficial to improving the power generation efficiency of the battery module 100.

[0091] In this embodiment, the photovoltaic system can be applied in a photovoltaic power station, such as a ground power station, a rooftop power station, a water surface power station, etc., or can also be applied to devices or apparatuses that use solar energy for power generation, such as a user solar power supply, a solar street lamp, a solar vehicle, a solar building, and so on. Of course, it can be understood that the application scenarios of the photovoltaic system are not limited thereto, that is to say, the photovoltaic system can be applied in all fields that require solar power generation. Taking a photovoltaic power generation system network as an example, the photovoltaic system may include a photovoltaic array, a busbar box, and an inverter. The photovoltaic array can be an array combination of multiple battery modules 100. For example, multiple battery modules 100 can form multiple photovoltaic arrays. The photovoltaic arrays are connected to the busbar box, and the busbar box can collect the current generated by the photovoltaic arrays. After the collected current flows through the inverter and is converted into alternating current required by the commercial power grid, it is connected to the commercial power grid to achieve solar power supply.

[0092] In the description of this specification, the descriptions with reference to terms such as "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials, or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0093] In addition, the above are only the preferred embodiments of the present application, and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A battery assembly, characterized in that: include: A plurality of battery strings, a first adhesive film, a pre-fixed film and a reflective member, wherein the battery string comprises a battery cell and a welding strip, the welding strip connects two adjacent battery cells in the battery string, a gap is formed between two adjacent battery strings, the first adhesive film and the pre-fixed film are respectively located on both sides of the battery cell, and the pre-fixed film fixes the welding strip to the battery cell; The reflector comprises a reflective portion and a connecting portion. The reflective portion is arranged corresponding to the gap and is located on a side of the pre-fixed film away from the battery sheet. The connecting portion protrudes from the reflective portion and passes through the gap to connect with the first adhesive film.

2. The battery assembly according to claim 1, characterized in that: The pre-fixed film is made of a first material, the connecting portion is made of a second material, and in the gap, a content of the second material is greater than a content of the first material.

3. The battery assembly according to claim 2, characterized in that: The ratio of the content of the second material to the content of the first material is greater than or equal to 5.

4. The battery assembly according to claim 2, characterized in that: The first material includes POE, and the second material includes EVA.

5. The battery assembly according to claim 1, characterized in that: In the thickness direction of the battery assembly, the thickness of the connecting portion is smaller than the thickness of the battery cell; Alternatively, the thickness of the connecting portion is greater than the thickness of the battery cell.

6. The battery assembly according to claim 1, characterized in that: The reflective portion includes a first adhesive layer, a reflective layer, and a second adhesive layer stacked in sequence, and the connecting portion protrudes from the first adhesive layer.

7. The battery assembly according to claim 1, characterized in that: The thickness of the reflective layer is 10 μm-300 μm.

8. The battery assembly according to claim 1, characterized in that: The width of the reflective layer is 0.5 mm-10 mm.

9. The battery assembly according to claim 1, characterized in that: The reflective layer includes at least one of aluminum, silver, chromium, silicon dioxide and titanium dioxide.

10. A photovoltaic system, characterized in that: A battery assembly comprising any one of claims 1 to 9.

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