Grid line structure, battery string and photovoltaic module
By designing multiple main and secondary gate cross-connections on the solar cell and adding bus bars to the edge of the cell, the current collection imbalance and welding tape contact problems are solved, and the current collection capacity is improved and the loss is reduced, ensuring that Balance of optical and electrical properties.
Patent Information
- Application Number
- CN202420883411.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-25
- Publication Date
- 2024-12-10
- Estimated Expiration
- 2034-04-25
AI Technical Summary
In solar cells, the current collection imbalance due to tiny gate lines morphology differences, and the transition zone of the welding tape is not fully contacted due to stress, resulting in weak current collection ability.
Multiple main gate lines are distributed spaced along the length of the cell, and a larger width of the main gate and the secondary gate are arranged at the edge of the cell to increase the width of the main gate and metal interconnection bar at the edge of the cell to enhance current collection. Ability to add bus bars to the back of the battery to reduce resistance.
The balance of current collection capacity and the reduction of transmission terminal loss are achieved without affecting power generation efficiency, ensuring the balance of optical gain and electrical loss.
Smart Images
Figure CN222146250U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of photovoltaics, in particular to a grid line structure, a battery string and a photovoltaic component. Background Art
[0002] At the slice or edge of the solar cell, the front main grid is usually set to a harpoon-shaped structure to reduce the height of the main grid and reduce the cell cracking caused by the yield strength of the welding ribbon during component welding. At the same time, the harpoon design is easier to collect edge current. The emerging 0BB connection technology usually needs to cancel the front harpoon design to better balance the current collection capacity between the welding ribbons.
[0003] In the design of cell graphics and the actual production process, although screen printing has high precision, the grid line morphology of each area may be different. Each cell is connected in series by several welding ribbons, which are connected in parallel, and the cells are connected in series. Therefore, as the efficiency of the cell increases, the slight difference in the grid line morphology will bring about an imbalance in the current collection inside the cell, which is mainly manifested as lateral battery collection. In addition, when the cell is connected by welding ribbons, because the welding ribbon needs to pass through the front of the cell and connect to the back, when the welding ribbon transitions from the front to the back, due to stress, part of the welding ribbon in the transition area does not fully contact the cell, and the secondary grid on both sides of the cell has a weaker current collection capacity. Utility Model Content
[0004] Based on this, it is necessary to provide a grid line structure. The grid line structure of the utility model can achieve a balance between optical gain and electrical loss when used to prepare solar cells, achieve a balance between the current collection capabilities of each welding strip, and reduce the loss at the transmission terminal.
[0005] An embodiment of the present application provides a gate line structure.
[0006] A grid line structure includes a main grid line and a sub-grid line. There are multiple main grid lines, and the multiple main grid lines are used to be connected to a battery cell. The multiple main grid lines are sequentially and spaced apart along the length direction of the battery cell. The width W1 of the first main grid line and the width W2 of the last main grid line along the length direction of the battery cell are both larger than the width W3 of the main grid lines at other positions. There are multiple sub-grid lines, and the multiple sub-grid lines are sequentially and spaced apart along the width direction of the battery cell. The sub-grid lines are cross-connected with the main grid lines.
[0007] In some embodiments, the width W1 of the first main grid line, the width W2 of the last main grid line, and the width W3 of the main grid lines at other positions along the length direction of the battery cell satisfy the following relationship: W1=1.5W3~2W3; W2=1.5W3~2W3.
[0008] In some embodiments, the width W1 of the first busbar line along the length direction of the cell is equal to the width W2 of the last busbar line.
[0009] In some embodiments, the widths of the busbar lines at other positions between the first busbar line and the last busbar line along the length direction of the cell are all equal.
[0010] In some embodiments, each of the auxiliary gate lines is vertically connected to the main gate line.
[0011] An embodiment of the present application also provides a battery string.
[0012] A battery string comprises a plurality of battery cells, a metal interconnection bar and a grid line structure, wherein a main grid line and a secondary grid line of the grid line structure are connected to the battery cells, a plurality of the battery cells are distributed in sequence, and adjacent battery cells are connected by the metal interconnection bar.
[0013] In some embodiments, the width of the metal interconnection strip is consistent with the width of the corresponding main grid line, wherein along the length direction of the battery cell, the width of the first metal interconnection strip and the width of the last metal interconnection strip are greater than the width of the metal interconnection strips at other positions.
[0014] In some embodiments, the battery string also includes a bus bar, which is connected to the edge of the back side of the battery cell and extends along the length direction of the battery cell. The bus bar is attached to the metal interconnection bar and the auxiliary grid line on the back side of the battery cell.
[0015] In some embodiments, the busbar is a tin-coated copper strip or copper foil;
[0016] And / or, the busbar has a thickness of 0.005 mm to 0.5 mm;
[0017] And / or, the width of the busbar is 5 mm to 20 mm;
[0018] And / or, the length of the bus bar is equal to the length of the battery cell.
[0019] An embodiment of the present application also provides a photovoltaic module.
[0020] A photovoltaic assembly comprises the battery string.
[0021] In the above-mentioned gate line structure, the width of the main gate line at the outermost position is increased, and correspondingly, the width of the metal interconnection strip at the outermost position is increased, which can enhance the current collection capacity at the edge of the battery cell, balance the current collection capacity between the metal interconnection strips, and reduce the loss at the transmission terminal; at the same time, the width of the main gate line and the metal interconnection strip at the middle position does not increase, will not cause a reduction in the light-receiving area, will not affect the power generation efficiency, and can achieve a balance between optical gain and electrical loss. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.
[0023] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings. In the following description, the same reference numerals represent the same parts.
[0024] FIG1 is a schematic diagram of a battery string according to an embodiment of the present utility model;
[0025] FIG. 2 is a side view of a battery string according to an embodiment of the present invention.
[0026] Description of Reference Numerals
[0027] 10. Battery string; 100. Grid line structure; 110. Main grid line; 120. Sub-grid line; 200. Battery cell; 300. Metal interconnection bar; 400. Bus bar. DETAILED DESCRIPTION
[0028] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.
[0029] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.
[0030] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0031] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.
[0032] In the description of the present utility model, "several" means more than one, "many" means more than two, "greater than", "less than", "exceed" etc. are understood to exclude the number itself, and "above", "below", "within" etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used to distinguish the technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.
[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the technical field of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.
[0034] The embodiment of the present application provides a grid line structure to solve the problem of unbalanced current collection inside the cell caused by the slight grid line morphology difference on the cell in the traditional technology, and the problem that when the cell is connected by the welding ribbon, the stress causes part of the welding ribbon in the transition area to not completely contact the cell when the welding ribbon transitions from the front of the cell to the back of the cell, resulting in weak current collection capability of the secondary grid at the edges of both sides of the cell. The grid line structure will be described below in conjunction with the accompanying drawings.
[0035] The gate line structure 100 provided in the embodiment of the present application is exemplified as shown in Fig. 1, which is a schematic diagram of the structure of a battery string 10 provided in the embodiment of the present application. The gate line structure 100 of the present application can be used to prepare a battery cell 200 to improve the current collection capability.
[0036] In order to more clearly illustrate the structure of the grid line structure 100, the grid line structure 100 will be introduced in conjunction with the accompanying drawings. For example, please refer to Figure 1, which is a schematic diagram of the structure of a battery string 10 provided in an embodiment of the present application. A grid line structure 100 includes a main grid line 110 and a secondary grid line 120. The number of main grid lines 110 is multiple. Multiple main grid lines 110 are used to connect to the battery cell 200. Multiple main grid lines 110 are distributed sequentially and at intervals along the length direction of the battery cell 200. The width W1 of the first main grid line 110 (shown as R1 in Figure 1) and the width W2 of the last main grid line 110 (shown as RN in Figure 1) along the length direction of the battery cell 200 are both larger than the width W3 of the main grid lines 110 (shown as R2, R3...R(N-1) in Figure 1) at other positions. There are multiple auxiliary gate lines 120 , which are sequentially and spaced apart along the width direction of the battery cell 200 . The auxiliary gate lines 120 are cross-connected with the main gate lines 110 .
[0037] In some embodiments, as shown in FIG1 , the width W1 of the first main gate line 110 at the edge, the width W2 of the last main gate line 110, and the width W3 of the main gate lines 110 at other positions satisfy the following relationship: W1=1.5W3~2W3; W2=1.5W3~2W3. It should be noted that the above 1.5W3~2W3 means that the value of W1 is 1.5 times to 2 times of W3, and the value of W2 is 1.5 times to 2 times of W3.
[0038] In some embodiments, the width W1 of the first busbar line 110 at the outermost position is equal to the width W2 of the last busbar line 110 .
[0039] In some embodiments, the widths of the bus bars 110 at other positions between the first bus bar 110 and the last bus bar 110 are all equal.
[0040] In some embodiments, each of the sub-gate lines 120 is vertically connected to the main gate line 110 .
[0041] An embodiment of the present application further provides a battery string 10 .
[0042] A battery string 10, as shown in FIG2, is a side schematic diagram of a battery string 10 according to an embodiment of the utility model, and the battery string 10 includes a plurality of battery cells 200, a metal interconnection bar 300, and a grid line structure 100. The main grid lines 110 and the auxiliary grid lines 120 of the grid line structure 100 are connected to the battery cells 200. The plurality of battery cells 200 are distributed in sequence, and adjacent battery cells 200 are connected by metal interconnection bars 300.
[0043] In some embodiments, the metal interconnection strip 300 may be a solder strip.
[0044] In some embodiments, the width of the metal interconnection bar 300 is consistent with the width of the corresponding main grid line 110. In particular, along the length direction of the cell 200, the width of the first metal interconnection bar 300 and the width of the last metal interconnection bar 300 at the edge are greater than the widths of the metal interconnection bars 300 at other positions.
[0045] Preferably, the width of the first metal interconnection strip 300 located at the outermost position is equal to the width of the last metal interconnection strip 300 .
[0046] Preferably, the widths of other metal interconnection strips 300 between the first metal interconnection strip 300 at the outermost position and the last metal interconnection strip 300 are all equal.
[0047] In some embodiments, the battery string 10 further includes a bus bar 400. The bus bar 400 is connected to the edge of the back of the battery cell 200, and the bus bar 400 extends along the length direction of the battery cell 200. The bus bar 400 is attached to the metal interconnection bar 300 and the secondary grid line 120 on the back of the battery cell 200.
[0048] In some embodiments, the bus bar 400 is a tin-coated copper tape or copper foil.
[0049] In some embodiments, the bus bar 400 has a thickness of 0.005 mm to 0.5 mm.
[0050] In some embodiments, the width of the bus bar 400 is 5 mm to 20 mm.
[0051] In some embodiments, as shown in FIG. 1 , the length of the bus bar 400 is equal to the length of the battery cell 200 .
[0052] It should be noted that, in the present application, the above-mentioned numerical interval (i.e., numerical range) is involved. If not otherwise specified, the distribution of the optional numerical values in the numerical interval is considered to be continuous, and includes the two numerical endpoints (i.e., the minimum value and the maximum value) of the numerical interval, and each numerical value between the two numerical endpoints. If not otherwise specified, when the numerical interval only refers to the integers in the numerical interval, it includes the two endpoint integers of the numerical range, and each integer between the two endpoints, which is equivalent to directly listing each integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be combined. In other words, unless otherwise specified, the numerical range disclosed in the present application should be understood to include any and all sub-ranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, a percentage, a ratio, etc. "Numerical interval" allows for broadly including quantitative intervals such as percentage intervals, ratio intervals, and ratio intervals.
[0053] In the present application, the current on the cell 200 is collected to the main grid line 110 through the secondary grid line 120, and then transmitted to the metal interconnection bar 300 through the main grid line 110. The transition area from the back of the cell 200 to the front of the cell 200 is the area with the largest current. Based on this, adding a bus bar 400 to the back of the cell 200 can reduce the resistance of this area. The bus bar 400 is completely connected in parallel with each metal interconnection bar 300, balancing the current output between each metal interconnection bar 300, thereby reducing the current mismatch between the cell 200 and the cell 200. In the transition area from the back side of the battery cell 200 to the front side of the battery cell 200, the metal interconnection bar 300 needs to be inserted in a Z-shape. Due to the influence of stress, there is a certain gap between the metal interconnection bar 300 at the edge of the battery cell 200 and the battery cell 200 (see Figure 2). Based on this, the present application can eliminate the current collection loss caused by the part of the metal interconnection bar 300 not contacting the battery cell 200 by attaching the bus bar 400 at the edge of the battery cell 200.
[0054] An embodiment of the present application also provides a photovoltaic module.
[0055] A photovoltaic module comprises a battery string 10. The photovoltaic module is not shown in the drawings.
[0056] In some embodiments, the photovoltaic module includes a front panel, a front film, a back film and a back panel, wherein the front panel, the front film, the cell string 10, the back film and the back panel are stacked in sequence and laminated to form a laminate.
[0057] In some embodiments, the photovoltaic module further comprises a packaging component, which is used to package the above-mentioned laminate. The packaging component can be a metal frame, such as an aluminum alloy frame.
[0058] To summarize, the above-mentioned gate line structure 100 increases the width of the main gate line 110 at the outermost position, and correspondingly, the width of the metal interconnection bar 300 at the outermost position is increased, so as to enhance the current collection capability at the edge position of the battery cell 200, balance the current collection capabilities between the metal interconnection bars 300, and reduce the loss at the transmission terminal; at the same time, the width of the main gate line 110 and the metal interconnection bar 300 at the middle position does not increase, that is, the width of the main gate line 110 at the middle position is smaller than the width of the main gate line 110 at the outermost position, which will not cause a reduction in the light receiving area and will not affect the power generation efficiency, and thus can achieve a balance between optical gain and electrical loss.
[0059] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.
[0060] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0061] The above-mentioned embodiments only express several implementation methods of the utility model, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent of the utility model. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the utility model, and these all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.
Claims
1. A gate line structure (100), characterized in that: The invention comprises a main grid line (110) and a secondary grid line (120), wherein the number of the main grid lines (110) is plural, the plurality of the main grid lines (110) are used to be connected to a battery cell (200), the plurality of the main grid lines (110) are spaced apart along the length direction of the battery cell (200), the width W1 of the first main grid line (110) and the width W2 of the last main grid line (110) along the length direction of the battery cell (200) are both greater than the width W3 of the main grid lines (110) at other positions, the number of the secondary grid lines (120) is plural, the plurality of the secondary grid lines (120) are spaced apart along the width direction of the battery cell (200), and the secondary grid lines (120) are cross-connected with the main grid lines (110).
2. The gate line structure (100) according to claim 1, characterized in that: Along the length direction of the battery cell (200), the width W1 of the first main grid line (110), the width W2 of the last main grid line (110), and the width W3 of the main grid lines (110) at other positions satisfy the following relationship: W1=1.5W3~2W3; W2=1.5W3~2W3.
3. The gate line structure (100) according to claim 1, characterized in that: Along the length direction of the cell sheet (200), the width W1 of the first main grid line (110) is equal to the width W2 of the last main grid line (110).
4. The gate line structure (100) according to any one of claims 1 to 3, characterized in that: Along the length direction of the battery cell (200), the widths of the main grid lines (110) at other positions between the first main grid line (110) and the last main grid line (110) are all equal.
5. The gate line structure (100) according to any one of claims 1 to 3, characterized in that: Each of the auxiliary gate lines (120) is vertically connected to the main gate line (110).
6. A battery string (10), characterized in that: The invention comprises a plurality of battery cells (200), a metal interconnection bar (300) and a gate line structure (100) according to any one of claims 1 to 5, wherein a main gate line (110) and a secondary gate line (120) of the gate line structure (100) are connected to the battery cells (200), the plurality of battery cells (200) are distributed in sequence, and adjacent battery cells (200) are connected via the metal interconnection bar (300).
7. The battery string (10) according to claim 6, characterized in that: The width of the metal interconnection bar (300) is consistent with the width of the corresponding main grid line (110), wherein along the length direction of the battery cell (200), the width of the first metal interconnection bar (300) and the width of the last metal interconnection bar (300) are both greater than the width of the metal interconnection bars (300) at other positions.
8. The battery string (10) according to claim 7, characterized in that: The battery string (10) further comprises a bus bar (400), the bus bar (400) being connected to the edge of the back side of the battery cell (200), and the bus bar (400) extending along the length direction of the battery cell (200), and the bus bar (400) being attached to the metal interconnection bar (300) and the secondary grid line (120) on the back side of the battery cell (200).
9. The battery string (10) according to claim 8, characterized in that: The busbar (400) is a tin-coated copper strip or copper foil; And / or, the bus bar (400) has a thickness of 0.005 mm to 0.5 mm; And / or, the width of the busbar (400) is 5 mm to 20 mm; And / or, the length of the bus bar (400) is equal to the length of the battery cell (200).
10. A photovoltaic module, characterized in that: A battery string (10) comprising the battery string (10) as claimed in any one of claims 6 to 9.