Back contact battery, battery string, battery assembly and photovoltaic system
By setting the positioning connection between the insulating structure and the conductive wire between the gate lines of the back contact battery, the problems of poor current acquisition effect and increased weight in the prior art are solved, and efficient current collection and stability enhancement are achieved.
Patent Information
- Application Number
- CN202421882633.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-05
- Publication Date
- 2025-07-04
- Estimated Expiration
- 2034-08-05
AI Technical Summary
In existing back contact batteries, in order to prevent the battery cell from short circuiting, the insulation layer is usually covered on the battery cell, resulting in poor current acquisition effect and increasing the battery weight.
An insulating structure is provided between the first gate line and the second gate line on the back of the battery cell. The conductive wire covers and connects the gate line, and is positioned and insulated through the insulating structure to avoid short circuits between adjacent gate lines or conductive wires.
It improves current collection and transmission efficiency, reduces production costs, and enhances battery stability and safety.
Smart Images
Figure CN223067452U_ABST
Abstract
Description
Technical Field
[0001] The present application belongs to the technical field of solar cells, and in particular relates to a back-contact cell, a cell string, a cell assembly and a photovoltaic system. Background Art
[0002] At present, solar cells are semiconductor devices that convert sunlight energy directly into electrical energy. Solar cells use the photovoltaic effect to excite electrons by absorbing photons, and conduct these electrons to generate current through a built-in electric field. Back-contact cells refer to solar cells with no electrodes on the light-facing side of the cell, and both the positive and negative electrodes are arranged on the backlight side of the cell. This can reduce the shading of the cell by the electrodes, increase the short-circuit current of the cell, and improve the energy conversion efficiency of the cell. However, in existing back-contact batteries, in order to prevent the cell from short-circuiting, an insulating layer is usually used to cover the cell. Although this method can prevent short circuits between grid lines, it will make the current collection effect poor and increase the weight of the battery. Utility Model Content
[0003] The present application provides a back-contact cell, a cell string, a cell assembly and a photovoltaic system, aiming to solve the problem of short circuit between adjacent grid lines or between adjacent conductive lines during use of photovoltaic cells.
[0004] The present application provides a back contact battery, comprising:
[0005] A battery cell, wherein the battery cell has a front side and a back side facing each other, the back side is provided with a first grid line and a second grid line, the first grid line and the second grid line extend along the first direction and are alternately distributed along the second direction, wherein the first grid line and the second grid line have opposite polarities, and the first direction and the second direction intersect;
[0006] Conductive lines, including first conductive lines and second conductive lines, the first conductive lines and the second conductive lines extend along the first direction and are alternately distributed along the second direction, the first conductive lines cover and connect the first gate lines, and the second conductive lines cover and connect the second gate lines;
[0007] An insulating structure is provided between the first gate line and the second gate line.
[0008] Furthermore, the insulating structure includes a first insulating segment and a second insulating segment, and the first insulating segment and the second insulating segment are respectively arranged on both sides of the first conductive line along the second direction.
[0009] Furthermore, the first insulating segment and the second insulating segment are in a strip shape and extend along the first direction.
[0010] Further, the first insulating section is discontinuously arranged; and / or
[0011] the second insulating section is discontinuously arranged.
[0012] Further, both the first insulating section and the second insulating section are discontinuously arranged, and a gap region is formed between the projections of the first insulating section and the second insulating section in the second direction.
[0013] Further, in the second direction, the first gate line and the second gate line are arranged at equal intervals and / or at unequal intervals.
[0014] Further, in the second direction, the width of the insulating structure is less than the distance between the first gate line and the adjacent second gate line.
[0015] Further, the first gate line is discontinuously arranged; and / or
[0016] the second gate line is discontinuously arranged.
[0017] The battery string provided by the embodiment of the present application includes the back contact battery described in any one of the above embodiments, and in the battery string, the back contact batteries are arranged along the first direction.
[0018] The battery module provided by the embodiment of the present application includes the battery string described in the above embodiment.
[0019] The photovoltaic system provided by the embodiment of the present application includes the battery module described in the above embodiment.
[0020] In the back contact battery, battery string, battery module and photovoltaic system of the embodiment of the present application, the back contact battery includes a battery cell, a conductive wire and an insulating structure. The battery cell has a front side and a back side facing away from each other, and first gate lines and second gate lines are provided on the back side. The first gate lines and the second gate lines extend along the first direction and are alternately distributed along the second direction. Among them, the first gate lines and the second gate lines have opposite polarities, the first direction and the second direction intersect. The conductive wire includes a first conductive wire and a second conductive wire. The first conductive wire and the second conductive wire extend along the first direction and are alternately distributed along the second direction. The first conductive wire covers and connects the first gate lines, and the second conductive wire covers and connects the second gate lines. The insulating structure is arranged between the first gate lines and the second gate lines. In this way, the insulating structure can be arranged between the first gate lines and the second gate lines. On the one hand, it can position the setting of the conductive wire to ensure the accurate position of the conductive wire. On the other hand, it can assist in insulating between the first gate lines and the second gate lines to avoid short circuits between adjacent gate lines or between adjacent conductive wires. Description of the Drawings
[0021] Figure 1It is a schematic partial plan view of a back-contact battery according to an embodiment of the present application;
[0022] Figure 2 It is another schematic partial plan view of a back-contact battery according to an embodiment of the present application;
[0023] Figure 3 It is still another schematic partial plan view of a back-contact battery according to an embodiment of the present application;
[0024] Figure 4 It is yet another schematic partial plan view of a back-contact battery according to an embodiment of the present application;
[0025] Figure 5 It is a schematic partial cross-sectional view of a back-contact battery according to an embodiment of the present application;
[0026] Figure 6 It is a schematic view of the structure of a battery string according to an embodiment of the present application;
[0027] Figure 7 It is a schematic view of the structure of a battery module according to an embodiment of the present application;
[0028] Figure 8 It is a schematic view of the structure of a photovoltaic system according to an embodiment of the present application.
[0029] Main element symbol description:
[0030] Back-contact battery 100, battery cell 10, front side 11, back side 12, first grid line 121, second grid line 122, conductive wire 20, first conductive wire 21, second conductive wire 22, arching structure 23, first busbar structure 30, second busbar structure 40, insulating structure 50, first insulating section 51, second insulating section 52, gap region 53, battery string 200, battery module 300, photovoltaic system 400. Detailed implementation manners
[0031] In order to make the objectives, technical solutions and advantages of the present application clearer and more understandable, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. The examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions from beginning to end. 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.
[0032] 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 drawings. These terms are only used 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. Therefore, they should not be construed as limitations on the present application.
[0033] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot 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 described features. In the description of the present application, "a plurality of" means two or more unless otherwise specifically defined.
[0034] 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 capable of mutual communication; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the internal connection 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.
[0035] 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 merely means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely means that the horizontal height of the first feature is lower than that of the second feature.
[0036] 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, 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 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.
[0037] In the related art, a solar cell is a semiconductor device that directly converts the energy of sunlight into electrical energy. The solar cell utilizes the photovoltaic effect, absorbs photons to excite electrons, and exports these electrons through a built-in electric field to generate current. A back-contact cell refers to a solar cell in which the light-facing surface of the cell has no electrodes, and the positive and negative electrodes are both disposed on the backlight side of the cell. This can reduce the shielding of the electrodes on the cell and increase the short-circuit current of the cell, thereby improving the energy conversion efficiency of the cell. However, in existing back-contact cells, in order to prevent the cell from short-circuiting, an insulating layer is usually covered on the cell. Although this method can prevent short-circuiting between the grid lines, it will result in poor current collection effect and increase the weight of the cell. In the present application, the insulating structure can be disposed between the first grid line and the second grid line. On the one hand, it can position the setting of the conductive wire to ensure the precise position of the conductive wire. On the other hand, it can assist in insulating between the first grid line and the second grid line to avoid short-circuiting between adjacent grid lines or adjacent conductive wires.
[0038] Embodiment 1
[0039] Please refer to Figure 1 and Figure 2 As shown in, a back-contact cell 100 provided by the present application includes a cell 10, a conductive wire 20, and an insulating structure 50. The cell 10 has opposite front surface 11 and back surface 12. The back surface 12 is provided with a first grid line 121 and a second grid line 122. The first grid line 121 and the second grid line 122 extend along a first direction and are alternately distributed along a second direction. Among them, the first grid line 121 and the second grid line 122 have opposite polarities, and the first direction intersects the second direction. The conductive wire 20 includes a first conductive wire 21 and a second conductive wire 22. The first conductive wire 21 and the second conductive wire 22 extend along the first direction and are alternately distributed along the second direction. The first conductive wire 21 covers and connects the first grid line 121, and the second conductive wire 22 covers and connects the second grid line 122. The insulating structure 50 is disposed between the first grid line 121 and the second grid line 122.
[0040] In the back-contact battery 100, battery string 200, battery module 300, and photovoltaic system 400 according to the embodiments of the present application, the back-contact battery 100 includes a cell 10, conductive wires 20, and an insulating structure 50. The cell 10 has opposite front surface 11 and back surface 12, and the back surface 12 is provided with a first grid line 121 and a second grid line 122. The first grid line 121 and the second grid line 122 extend along a first direction and are alternately distributed along a second direction. Among them, the first grid line 121 and the second grid line 122 have opposite polarities, and the first direction and the second direction intersect. The conductive wires 20 include a first conductive wire 21 and a second conductive wire 22. The first conductive wire 21 and the second conductive wire 22 extend along the first direction and are alternately distributed along the second direction. The first conductive wire 21 covers and connects the first grid line 121, and the second conductive wire 22 covers and connects the second grid line 122. The insulating structure 50 is disposed between the first grid line 121 and the second grid line 122. In this way, the insulating structure 50 can be disposed between the first grid line 121 and the second grid line 122. On the one hand, it can position the arrangement of the conductive wires 20 to ensure the precise position of the conductive wires 20. On the other hand, it can assist in insulating between the first grid line 121 and the second grid line 122 to avoid short circuits between adjacent grid lines or adjacent conductive wires 20.
[0041] In the embodiments of the present application, two regions with opposite polarities can be formed on the back surface 12 of the cell 10. The first grid line 121 can be disposed in the first electrode region, and the second grid line 122 can be disposed in the second electrode region. That is to say, the first grid line 121 and the second grid line 122 can guide the current generated by the cell 10. At the same time, the first conductive wire 21 is disposed on the first grid line 121, and the second conductive wire 22 is disposed on the second grid line 122. The first conductive wire 21 and the second conductive wire 22 are also conductive wires 20 with opposite polarities. That is to say, the first conductive wire 21 and the second conductive wire 22 are also alternately distributed along the second direction. Except for the edge positions, both sides adjacent to each first conductive wire 21 are second conductive wires 22, and both sides adjacent to each second conductive wire 22 are first conductive wires 21.
[0042] In this embodiment, the gate lines and the conductive lines 20 are interconnected to form a continuous current transmission path. The first conductive line 21 is connected to the first gate line 121 and extends to the edge of the cell 10 to output current. Similarly, the second conductive line 22 is connected to the second gate line 122 and extends to the opposite edge to output current. In this way, it is ensured that the current generated by each cell 10 can be collected and transmitted quickly and efficiently through multiple paths. Thus, the conductive lines 20 can cooperate with the gate lines to provide more lead-out paths for the current, improve the current collection effect on the cell 10, and in the case of broken gates, hidden cracks, etc., the current can be led out through the conductive lines 20, thereby ensuring stable current collection. At the same time, since the conductive lines 20 assist in carrying the current collection and transmission, the production costs brought by the silver paste / metallization process materials and equipment of the cell 10 can be further reduced.
[0043] Specifically, in the back-contact cell 100 of the embodiment of the present application, an insulating structure 50 can be provided between the first gate line 121 and the second gate line 122. The insulating structure 50 can insulate the adjacent first gate line 121 and second gate line 122 to avoid short-circuiting between the first gate line 121 and the second gate line 122. At the same time, during the preparation of the back-contact cell 100, the first gate line 121 and the second gate line 122 can be first prepared on the cell 10, and then the insulating structure 50 can be provided between the first gate line 121 and the adjacent second gate line 122. Finally, taking the insulating structure 50 as a positioning anchor point, the first conductive line 21 and the second conductive line 22 are respectively laid on the first gate line 121 and the second gate line 122. In this way, the insulating structure 50 can play a positioning role for the first conductive line 21 and the second conductive line 22. When more gate lines and conductive lines 20 need to be provided on the cell 10, the insulating structure 50 can ensure the stable connection between the conductive lines 20 and the gate lines.
[0044] It should be noted that in the embodiment of the present application, the material and type of the insulating structure 50 are not limited to meet different requirements.
[0045] In addition, in this embodiment, the shape of the cell 10 is not limited to meet different requirements. For example, the cell 10 can be rectangular or a square whole cell provided with scribe lines. Then, the square whole cell is designed to correspond to a single rectangular cell 10 or a single cell 10 segment (two segments, three segments, etc.) after cutting. The main feature of such a cell 10 is that there are no gate lines and electrode structures on the front surface 11, and the positive and negative electrode structures are alternately distributed on the back surface 12 of the cell 10 in sequence.
[0046] In the embodiments of the present application, the number and respective dimensional ranges of the first grid lines 121 and the second grid lines 122 are not limited either, so as to meet different requirements. For example, when the width of the battery cell 10 is less than or equal to 210 mm, the number of the first grid lines 121 and the second grid lines 122 can be 100 - 800, the spacing between the first grid lines 121 and the second grid lines 122 is 0.2 - 2 mm, and the widths of the first grid lines 121 and the second grid lines 122 in the second direction can be 10 - 300 μm.
[0047] Exemplarily, the first grid lines 121 of the back contact battery 100 can be positive electrodes, and the second grid lines 122 can be negative electrodes. An insulating structure 50 is provided between adjacent grid lines of the battery cell 10 (that is, an insulating structure 50 is provided between the first grid lines 121 and the adjacent second grid lines 122), to prevent short - circuit caused by the lap of opposite - sex electrodes and improve the durability and safety of the battery cell 10. Of course, in other embodiments, it can be the opposite, that is to say, the first grid lines 121 of the back contact battery 100 can be negative electrodes, and the second grid lines 122 can be positive electrodes, which is not specifically limited herein.
[0048] Furthermore, the alternating distribution of the first grid lines 121 and the second grid lines 122 and their precise connection with the conductive wires 20 enable the current to be collected and transmitted more effectively, reducing the electrical losses of the fine grids and / or the main grids. At the same time, the reasonable setting of the current - collecting structure ensures the reliable connection of the conductive wires 20, enhancing the stability and reliability of the overall structure. In this way, a more efficient current - collecting and transmitting path is provided in the back contact battery 100, making the back contact battery 100 have lower electrical losses, production costs and higher power in practical applications.
[0049] In some embodiments, the back contact battery 100 further includes a current - collecting structure, and the current - collecting structure includes a first current - collecting structure 30 and a second current - collecting structure 40. The first current - collecting structure 30 and the second current - collecting structure 40 are arranged on both side edges of the back surface 12 of the same battery cell 10, the polarities of the first current - collecting structure 30 and the second current - collecting structure 40 are opposite, and the first current - collecting structure 30 of the battery cell 10 is electrically connected to the second current - collecting structure 40 of the adjacent battery cell 10. The first current - collecting structure 30 can be used to connect with the first grid lines 121 and the first conductive wires 21, and the second current - collecting structure 40 can be used to connect with the second grid lines 122 and the second conductive wires 22.
[0050] Further, the number of conductive wires 20 provided on the back surface 12 is the same as that of the grid lines, which is equivalent to providing a dense metal carrier film layer on the back surface 12 of the cell 10, improving the load performance of the cell 10 and the module, as well as providing more current extraction paths. In this way, the conductive wires 20 can cooperate with the grid lines to provide more current extraction paths, improving the current collection effect on the cell 10. In the case of broken grids, hidden cracks, etc., the first current collecting structure 30 and the second current collecting structure 40 can export the current through the conductive wires 20, thereby ensuring stable current collection. At the same time, since the conductive wires 20 assist in carrying and transmitting the current collection, the production costs brought by the silver paste / metalization process materials and equipment of the cell 10 can be further reduced.
[0051] In the embodiments of the present application, the form of the conductive wires 20 is not limited either to meet different requirements. For example, the cross-sectional shape of the conductive wires 20 can be circular, triangular, quasi-triangular, or rectangular. Of course, the cross-sectional shapes of the first conductive wire 21 and the second conductive wire 22 can be the same or different, and the cross-section of a single conductive wire can also be different. When it is a plane, it can ensure a more secure and better welding effect.
[0052] In addition, in the embodiments of the present application, the form of the current collecting structure is not limited to meet different requirements. For example, the current collecting structure can be a conductive material such as a wire, a bus bar, or a conductive tape.
[0053] Embodiment 2
[0054] Please refer to Figure 1 and Figure 2 , in some alternative embodiments, the insulating structure 50 includes a first insulating section 51 and a second insulating section 52, and the first insulating section 51 and the second insulating section 52 are respectively arranged on both sides of the first conductive wire 21 along the second direction.
[0055] In this way, the first insulating section 51 and the second insulating section 52 can be respectively arranged on both sides of the first conductive wire 21, thereby insulating the first conductive wire 21 and the two adjacent second conductive wires 22, and preventing the first conductive wire 21 and the second conductive wire 22 from being short-circuited.
[0056] Specifically, during the actual preparation process, taking the first grid line 121 as a reference, the first insulating section 51 and the second insulating section 52 can be respectively arranged on both sides of the first grid line 121 along the second direction. This enables the first insulating section 51 and the second insulating section 52 to play a positioning role in the arrangement of the conductive wires 20. The precise arrangement of the first insulating section 51 and the second insulating section 52 on both sides of the first conductive wire 21 ensures the stable position of the conductive wires 20 and prevents them from shifting during production and use.
[0057] Embodiment 3
[0058] Please refer to Figure 1and Figure 2 In some alternative embodiments, the first insulating segment 51 and the second insulating segment 52 are strip-shaped and extend along the first direction.
[0059] Thus, the first insulating segment 51 and the second insulating segment 52 can be respectively arranged on both sides of the first conductive wire 21 and are arranged parallel to the first gate line 121 and the first conductive wire 21. In this way, the first insulating segment 51 and the second insulating segment 52 can more completely fill the position between the first conductive wire 21 and the second conductive wire 22, ensuring complete isolation between the first conductive wire 21 and the second conductive wire 22.
[0060] Specifically, the first insulating segment 51 and the second insulating segment 52 extend in a strip shape, enabling them to fully fill the space between the first conductive wire 21 and the second conductive wire 22, achieving a good insulation effect. The insulating segments are arranged parallel to the conductive wire 20 and the gate line, ensuring that each insulating segment can be accurately positioned and providing a stable isolation effect.
[0061] Embodiment Four
[0062] Please refer to Figure 3 and Figure 4 In some alternative embodiments, the first insulating segment 51 is intermittently arranged; and / or
[0063] the second insulating segment 52 is intermittently arranged.
[0064] Thus, by intermittently arranging the first insulating segment 51 and the second insulating segment 52, insulating materials can be saved, and at the same time, the weight of the back-contact battery 100 can be reduced.
[0065] Specifically, the intermittent pattern of the insulating segments can be flexibly designed according to the actual requirements of the battery cell 10, ensuring both the insulation effect and maximizing material savings. By flexibly designing the intermittent pattern of the insulating segments and combining the application of high-precision manufacturing processes and high-quality materials, the insulation effect and structural stability of the back-contact battery 100 are ensured, thereby improving the overall performance and economy of the back-contact battery 100.
[0066] Furthermore, in the embodiments of the present application, the number of intermittent segments of the first insulating segment 51 and the second insulating segment 52 is not limited, nor is the specific length of the first insulating segment 51 and the second insulating segment 52 limited to meet different requirements. In one embodiment, the first insulating segment 51 and the second insulating segment 52 extend along the first direction, and two segments of the first insulating segment 51 and two segments of the second insulating segment 52 can be respectively arranged on both sides of the first conductive wire 21; at the same time, on both sides of another first conductive wire 21, three segments of the first insulating segment 51 and three segments of the second insulating segment 52 can be respectively arranged.
[0067] Embodiment Five
[0068] Please refer toFigure 3 and Figure 4 , in some alternative embodiments, both the first insulating segment 51 and the second insulating segment 52 are intermittently arranged, and a gap region 53 is formed between the projections of the first insulating segment 51 and the second insulating segment 52 in the second direction.
[0069] In this way, the first insulating segment 51 and the second insulating segment 52 are respectively arranged on both sides of the first conductive wire 21, and the gap positions between two adjacent first insulating segments 51 correspond to the second insulating segment 52, and the gap positions between two adjacent second insulating segments 52 correspond to the first insulating segment 51. In this way, the first insulating segment 51 and the second insulating segment 52 can perform the functions of insulation and positioning, while minimizing the amount of insulating glue used.
[0070] Specifically, both the first insulating segment 51 and the second insulating segment 52 are intermittently arranged, and a gap region 53 is formed between their projections in the second direction. That is to say, the gap positions between two adjacent first insulating segments 51 are arranged corresponding to the second insulating segment 52, and the gap positions between two adjacent second insulating segments 52 correspond to the first insulating segment 51. That is to say, the projections of the first insulating segment 51 and the second insulating segment 52 on the first conductive wire 21 are separated from each other without overlapping positions. In this way, both the insulation effect is ensured and the materials are saved to the greatest extent.
[0071] Furthermore, in some embodiments, the first insulating segment 51 and the second insulating segment 52 can also be in a dot shape. The first insulating segment 51 and the second insulating segment 52 are respectively dot - arranged on both sides of the first conductive wire 21, and the dot - shaped first insulating segment 51 and the second insulating segment 52 are arranged along the first direction. In this way, both the insulation and positioning effects are ensured and the materials are saved to the greatest extent.
[0072] Embodiment Six
[0073] Please refer to Figure 1 and Figure 2 , in some alternative embodiments, in the second direction, the first gate line 121 and the second gate line 122 are arranged at equal intervals and / or non - equal intervals.
[0074] In this way, the first gate line 121 and the second gate line 122 can be arranged at equal intervals, or non - equal intervals, or partially at equal intervals and partially at non - equal intervals. In this way, corresponding adjustments can be made according to actual needs.
[0075] Specifically, the spacing between the first gate line 121 and the second gate line 122 is flexibly adjusted according to actual requirements. An equal-spacing setting can ensure uniform current distribution and improve the overall efficiency of the back-contact battery 100; a non-equal-spacing setting can optimize the current conduction path for specific application scenarios and reduce problems such as local overheating or excessive resistance. A combined setting with partial equal-spacing and partial non-equal-spacing can combine the advantages of both and be flexibly adjusted according to specific requirements to optimize the performance of the back-contact battery 100.
[0076] Furthermore, an equal-spacing setting is relatively simple in the manufacturing process and is suitable for large-scale production. A non-equal-spacing setting is optimized in certain areas of the battery chip 10 according to the current density and heat distribution to reduce local hot spots and excessive resistance problems. It is applicable to application scenarios that require special current distribution or thermal management, such as high-power battery modules 300. By combining the advantages of equal-spacing and non-equal-spacing and being flexibly adjusted according to specific requirements, the overall performance of the battery module 300 is optimized.
[0077] Embodiment Seven
[0078] Please refer to Figure 1 and Figure 2 In some alternative embodiments, in the second direction, the width of the insulating structure 50 is less than the distance between the first gate line 121 and the adjacent second gate line 122.
[0079] In this way, the insulating structure 50 can prevent the short circuit between the first gate line 121 and the second gate line 122, and at the same time prevent the short circuit between the first conductive wire 21 and the second conductive wire 22. The width of the insulating structure 50 in the second direction being less than the distance between the first gate line 121 and the adjacent second gate line 122 enables the insulating structure 50 to be arranged between any first gate line 121 and second gate line 122 without contacting the gate lines, ensuring the stable operation of the gate lines.
[0080] Embodiment Eight
[0081] Please refer to Figure 1 and Figure 5 In some alternative embodiments, the first gate line 121 is intermittently arranged; and / or
[0082] The second gate line 122 is intermittently arranged.
[0083] In this way, the intermittent arrangement of the gate lines can save the materials for preparing the gate lines and reduce costs. After the gate lines are interrupted, the conductive wires 20 can be connected to the gate lines to ensure that each section of the interrupted gate lines can conduct the collected current into the busbar structure.
[0084] Specifically, the discontinuous design of the grid lines enables the grid lines to be segmented in a certain area. In this way, the conductive wire 20 can be connected to the grid lines at the discontinuities of the grid lines, ensuring that even at the places where the grid lines are disconnected, each segment of the grid lines can effectively conduct the collected current into the busbar structure. This optimizes the material usage, reduces the production cost, and at the same time ensures the normal conduction of the current and the overall performance of the component. The connection design of the conductive wire 20 at the discontinuities of the grid lines should ensure good electrical contact and minimum resistance to ensure efficient conduction of the current.
[0085] In some embodiments, regardless of how the first grid line 121 is discontinuously arranged, there must be a segment of the first grid line 121 connected to the first busbar structure 30. Similarly, regardless of how the second grid line 122 is discontinuously arranged, there must be a segment of the second grid line 122 connected to the second busbar structure 40 to ensure stable connection.
[0086] In the embodiments of the present application, the discontinuity positions and discontinuity distances of the first grid line 121 and the second grid line 122 are not limited to meet different requirements. In one example, the first grid line 121 and the second grid line 122 can be regularly and uniformly discontinuously arranged.
[0087] In some alternative embodiments, the conductive wire 20 is a metal wire. In this way, the metal wire has good electrical conductivity and mechanical properties, can assist the grid lines in current transfer, and avoid open circuits.
[0088] Specifically, the conductive wire 20 can cover the grid lines. Of course, in other embodiments, the grid lines can be longer than the conductive wire 20. For example, the exposed length range at the ends of the grid lines can be 0 - 50 mm, which can reduce the material usage and cost of the conductive wire 20. Of course, in this case, if the grid lines are discontinuously arranged, the conductive wire 20 needs to cover and connect all segments of the grid lines, that is, the grid line segments farthest from the busbar structure will also be connected together by the conductive wire 20 to ensure current collection.
[0089] In the embodiments of the present application, the cross-sectional shape of the conductive wire 20 is not limited, and the conductive wire 20 is not limited to circular, triangular, polygonal, flat, or structures with special treatments such as reflective structures. For example, when the conductive wire 20 is circular, the diameter of the conductive wire 20 can be 0.05 - 0.5 mm. When the conductive wire 20 is extremely thin, the triangular shape may not achieve the ideal light reflection state, so a round wire conductive wire 20 is preferably used, which improves the bifaciality compared to the currently used flat conductive wire 20.
[0090] Please refer to Figure 5 , in some alternative embodiments, the conductive wire 20 forms an arch structure 23 at the discontinuity positions of the first grid line 121 and the second grid line 122.
[0091] Thus, the arch structure 23 can effectively connect two discontinuous grid lines, improving the stability and durability during use, avoiding warping, and preventing poor contact caused by mechanical stress or temperature changes. This design can not only provide more reliable electrical contact, but also effectively disperse and absorb the deformation caused by mechanical stress or thermal expansion and contraction, thereby preventing poor contact or current loss. It is suitable for working under high-temperature or stress conditions to ensure the long-term stability and performance of the battery module 300.
[0092] Embodiment Nine
[0093] Please refer to Figure 1 and Figure 6 The battery string 200 provided by the embodiment of the present application includes the back-contact battery 100 of any one of the above embodiments, and the back-contact batteries 100 are arranged in the first direction in the battery string 200.
[0094] In the embodiment of the present application, the battery string 200 can be formed by sequentially connecting a plurality of sheet-like back-contact batteries 100 in series and connecting them through welding tapes and busbars. It can be understood that in the battery string 200, the battery string 200 can include two battery cells 10 connected in series, three battery cells 10 connected in series, or other more numbers of battery cells 10. Specifically, the number of battery cells 10 to be connected in series can be determined according to actual use conditions. In addition, in the embodiment of the present application, the size and type of the back-contact battery 100 are not limited either. The specifications and sizes of adjacent battery cells 10 can be the same or different to meet different requirements.
[0095] In the embodiment of the present application, the specific connection method of adjacent battery cells 10 is not limited to meet different requirements. In one embodiment, at least a part of the edges of two adjacent battery cells 10 are stacked together; in another embodiment, two adjacent battery cells 10 can be arranged at intervals. The distance between two adjacent battery cells 10 is within a suitable range, which can avoid the small operation space and large welding difficulty caused by too small a distance, and can also avoid wasting the component space and increasing the cost caused by too large a distance.
[0096] Embodiment Ten
[0097] Please refer to Figure 1 and Figure 7 The battery module 300 provided by the embodiment of the present application includes the battery string 200 of the above embodiment.
[0098] The battery module 300 provided by the present application realizes the goals of high space utilization rate, multi-path high current transmission efficiency, and high reliability through reasonable arrangement of battery cells 10, layout of grid lines and conductive wires 20, and setting of busbar structures, and is applicable to various high-performance battery application scenarios.
[0099] In this embodiment, multiple back-contact batteries 100 in the battery assembly 300 can be connected in series in sequence to form a battery string 200, thereby achieving the series connection and current collection output. For example, the connection of the battery cells 10 can be achieved by setting solder tapes (bus bars, interconnection bars), conductive backplates, etc.
[0100] It can be understood that in such an embodiment, the battery assembly 300 may further include a frame, a backplate, a photovoltaic glass, and an encapsulant film. The encapsulant film can be filled between the front side 11 and the back side 12 of the back-contact battery 100, as well as between the photovoltaic glass, adjacent battery cells 10, etc. As a filler, it can be a transparent colloid with good light transmittance and aging resistance. For example, the encapsulant film can be an EVA encapsulant film or a POE encapsulant film, and specific selection can be made according to the actual situation, which is not limited herein.
[0101] The photovoltaic glass can cover the encapsulant film on the front side 11 of the back-contact battery 100. The photovoltaic glass can be ultra-white glass, which has a high light transmittance, high transparency, and excellent physical, mechanical, and optical properties. For example, the light transmittance of the ultra-white glass can reach more than 92%, and it can protect the back-contact battery 100 without significantly affecting its efficiency. At the same time, the encapsulant film can bond the photovoltaic glass and the back-contact battery 100 together, and the presence of the encapsulant film can seal and insulate the back-contact battery 100 and prevent water and moisture.
[0102] The backplate can be attached to the encapsulant film on the back side 12 of the back-contact battery 100. The backplate can protect and support the back-contact battery 100, and has reliable insulation, water resistance, and aging resistance. The backplate can have multiple choices and is usually tempered glass, plexiglass, aluminum alloy TPT composite film, etc., and its specific setting can be determined according to the specific situation, which is not limited herein. The whole composed of the backplate, the back-contact battery 100, the encapsulant film, and the photovoltaic glass can be set on the frame. The frame, as the main external support structure of the entire battery assembly 300, can stably support and install the battery assembly 300. For example, the battery assembly 300 can be installed at the required installation position through the frame.
[0103] In the embodiment of the present application, multiple battery cells 10 can be arranged along the first direction to form a battery string 200, thereby achieving the series connection and current collection output. The extending direction of the grid lines and the conductive wires 20 is also the first direction. In this way, the current can flow from the battery cells 10 to the grid lines and the conductive wires 20 and then to the current collection structure, reducing the fine grid loss and / or the main grid loss, and thus improving the component power.
[0104] In some embodiments, the battery assembly 300 can be provided with a current collection structure such as conductive wires 20 or solder tapes to achieve the conductive output of the battery string 200.
[0105] Embodiment XI
[0106] Please refer to Figure 1 and Figure 8 The photovoltaic system 400 provided by the embodiment of the present application includes the battery assembly 300 of the above embodiment.
[0107] In the back-contact battery 100, battery string 200, battery assembly 300 and photovoltaic system 400 of the embodiment of the present application, the back-contact battery 100 includes a battery chip 10, a conductive wire 20 and an insulating structure 50. The battery chip 10 has opposite front surface 11 and back surface 12. The back surface 12 is provided with a first grid line 121 and a second grid line 122. The first grid line 121 and the second grid line 122 extend along a first direction and are alternately distributed along a second direction. Among them, the first grid line 121 and the second grid line 122 have opposite polarities, and the first direction intersects the second direction. The conductive wire 20 includes a first conductive wire 21 and a second conductive wire 22. The first conductive wire 21 and the second conductive wire 22 extend along the first direction and are alternately distributed along the second direction. The first conductive wire 21 covers and connects the first grid line 121, and the second conductive wire 22 covers and connects the second grid line 122. The insulating structure 50 is arranged between the first grid line 121 and the second grid line 122. Thus, the insulating structure 50 can be arranged between the first grid line 121 and the second grid line 122. On the one hand, it can position the arrangement of the conductive wire 20 to ensure the accurate position of the conductive wire 20. On the other hand, it can assist in insulating between the first grid line 121 and the second grid line 122 to avoid short circuits between adjacent grid lines or between adjacent conductive wires 20.
[0108] In this embodiment, the photovoltaic system 400 can be applied in a photovoltaic power station, such as a ground power station, a rooftop power station, a water surface power station, etc., and 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 car, a solar building, etc. Of course, it can be understood that the application scenarios of the photovoltaic system 400 are not limited to this. That is to say, the photovoltaic system 400 can be applied in all fields that require solar power generation. Taking the photovoltaic power generation system network as an example, the photovoltaic system 400 can include a photovoltaic array, a busbar box and an inverter. The photovoltaic array can be an array combination of multiple battery assemblies 300. For example, multiple battery assemblies 300 can form multiple photovoltaic arrays. The photovoltaic arrays are connected to the busbar box. 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.
[0109] In the description of this specification, the descriptions referring to terms such as "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples", etc., 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 representations of the above terms do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples.
[0110] 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 principles of the present application shall be included within the protection scope of the present application.
Claims
1. A back-contact battery, characterized in that, Comprising: A battery cell having opposite front and back surfaces, with first grid lines and second grid lines provided on the back surface. The first grid lines and the second grid lines extend along a first direction and are alternately distributed along a second direction. Among them, the first grid lines and the second grid lines have opposite polarities, and the first direction intersects the second direction; Conductive wires, including a first conductive wire and a second conductive wire, which extend along the first direction and are alternately distributed along the second direction. The first conductive wire covers and connects the first grid lines, and the second conductive wire covers and connects the second grid lines; An insulating structure provided between the first grid lines and the second grid lines.
2. The back contact battery according to claim 1, characterized in that, The insulating structure includes a first insulating section and a second insulating section, and the first insulating section and the second insulating section are respectively provided on both sides of the first conductive wire along the second direction.
3. The back-contact battery according to claim 2, characterized in that, The first insulating section and the second insulating section are strip-shaped and extend along the first direction.
4. The back contact battery according to claim 3, characterized in that, The first insulating section is intermittently provided; and / or The second insulating section is intermittently provided.
5. The back-contact battery according to claim 4, characterized in that, Both the first insulating section and the second insulating section are intermittently provided, and a gap region is formed between the projections of the first insulating section and the second insulating section in the second direction.
6. The back-contact battery according to claim 1, wherein, In the second direction, the first grid lines and the second grid lines are arranged at equal intervals and / or non-equal intervals.
7. The back contact battery according to claim 1, characterized in that, In the second direction, the width of the insulating structure is smaller than the distance between the first grid line and the adjacent second grid line.
8. The back contact battery according to claim 1, characterized in that, The first grid line is intermittently provided; and / or The second grid line is intermittently provided.
9. A battery string, characterized in that, Comprising a back-contact battery according to any one of claims 1-8, wherein in the battery string, the back-contact batteries are arranged along the first direction.
10. A battery assembly, characterized in that, Comprising the battery string according to claim 9.
11. A photovoltaic system, characterized in that, Comprising a battery assembly according to claim 10.