Strip battery modules, solar cells and photovoltaic modules

Abstract

The present invention provides a strip-shaped battery module, a solar cell, and a photovoltaic module. The strip-shaped battery module includes a first main grid located on a first surface and a second main grid located on a second surface. The first and second main grids are respectively arranged at two opposite edges of the strip-shaped battery module. The strip-shaped battery module also includes test electrodes located on the second surface. The test electrodes and the first main grid are distributed on the same edge of the strip-shaped battery module, with the upper and lower electrodes correspondingly arranged. The provision of the test electrodes enables testing using upper and lower probes, which more closely resembles the performance of the strip-shaped battery module after slicing. Furthermore, the test probes used for conventional whole-sheet solar cells can be used, eliminating the need for repeated adjustment of the test probes.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaics, and in particular to a strip-shaped battery module, a solar cell sheet and a photovoltaic assembly that are convenient for testing. Background Art

[0002] With the rapid development of photovoltaic technology, photovoltaic shingled modules and patchwork technology have become the key development directions of the industry by eliminating or reducing the gaps between panels to maximize the use of module area and increase module power.

[0003] The shingled assembly includes several parallel battery strings, each of which includes several battery cells. The front main grid and the back main grid of each battery cell are located on two opposite sides of the battery cell, and the front main grid of the battery cell is connected to the back main grid of the adjacent battery cell by overlapping conductive glue. The battery cells at the beginning and end of the battery string need to be welded with bus bars for current extraction.

[0004] The front main grid and the back main grid are located on two opposite sides, which brings a lot of inconvenience to the testing of the battery cell and has poor test stability. Summary of the Invention

[0005] The object of the present invention is to provide a strip-shaped battery module, a solar cell and a photovoltaic assembly that are easy to test.

[0006] In order to achieve the above application objectives, the present invention adopts the following technical solutions:

[0007] A strip battery module includes a first main grid located on a first surface and a second main grid located on a second surface. The first main grid and the second main grid are respectively arranged at two opposite edges of the strip battery module. The strip battery module also includes a test electrode located on the second surface. The test electrode and the first main grid are distributed on the same edge of the strip battery module and are arranged correspondingly above and below.

[0008] Furthermore, the first main gate includes alternately arranged first narrow main gate segments and first wide main gate segments, and the test electrode includes test electrode blocks corresponding to a plurality of first wide main gate segments one by one;

[0009] Alternatively, the first main grid is a first through-type electrode, and the test electrode includes a plurality of test electrode blocks corresponding to different positions of the first through-type electrode.

[0010] Furthermore, the first surface is the front surface, and the second surface is the back surface.

[0011] Furthermore, the strip-shaped battery module further includes a grid-line back electric field located on the second surface, the grid-line back electric field includes a busbar and a fine grid located on one side of the busbar, and the test electrode is electrically connected to a portion of the fine grid.

[0012] A solar cell comprises a plurality of strip-shaped battery regions arranged at intervals along a first direction and a partitioning region located between adjacent strip-shaped battery regions. The strip-shaped battery regions include a first main grid located on a first surface and a second main grid located on a second surface. The first main grid and the second main grid are respectively arranged at two oppositely disposed edges of the strip-shaped battery module. The strip-shaped battery region further comprises a test electrode located on the second surface. The test electrode and the first main grid are distributed on the same edge of the strip-shaped battery module and are arranged correspondingly above and below.

[0013] Furthermore, the first main gate includes alternately arranged first narrow main gate segments and first wide main gate segments, and the test electrode includes test electrode blocks corresponding one-to-one to several first wide main gate segments; or, the first main gate is a first straight-through electrode, and the test electrode includes several test electrode blocks corresponding to different positions of the first straight-through electrode.

[0014] Furthermore, the first surface is the front surface, and the second surface is the back surface.

[0015] Furthermore, the strip-shaped battery area also includes a grid-line-shaped back electric field located on the second surface, and the grid-line-shaped back electric field includes a bus bar and a fine grid located on one side of the bus bar, at least a portion of the second bus bar is connected to the bus bar, and the test electrode is electrically connected to a portion of the fine grid.

[0016] Furthermore, it also includes a first silver interconnect electrode located in the dividing area of ​​the first surface, the first silver interconnect electrode electrically connecting the first electrode pattern of the two adjacent strip-shaped battery areas; and a second silver interconnect electrode located in the dividing area of ​​the second surface, the second silver interconnect electrode electrically connecting the second electrode pattern of the two adjacent strip-shaped battery areas.

[0017] Furthermore, the width of the second silver interconnecting electrodes along the first direction is between 0.3 mm and 2 mm.

[0018] Furthermore, the first surface is the front side, the first electrode pattern also includes a first fine grid vertically connected to the first main grid on one side of the first main grid, the first silver interconnect electrode is a plurality of silver grid lines, and the plurality of silver grid lines connect 5%-50% of the first fine grids in the first electrode pattern with adjacent first electrode patterns.

[0019] Furthermore, the second surface is the back surface, and the second silver interconnect electrode includes a plurality of silver electrode blocks or a plurality of gate line groups arranged at intervals.

[0020] Furthermore, the second main gate includes alternately arranged second narrow main gate segments and second wide main gate segments, a plurality of silver electrode blocks are connected one-to-one with the plurality of second wide main gate segments, or a plurality of gate line groups are connected one-to-one with the plurality of second wide main gate segments; or, the second main gate is a second straight-through electrode, a plurality of silver electrode blocks or a plurality of gate line groups are all connected to the second straight-through electrode.

[0021] A photovoltaic assembly comprises the aforementioned strip-shaped battery module, wherein two adjacent strip-shaped battery modules are connected by overlapping their edges.

[0022] The beneficial effects of the present invention are: by setting test electrodes, the present invention can use upper and lower probes for testing, which is closer to the performance of the strip battery module formed after slicing; and can use the same test probes as traditional whole solar cells, eliminating the process of adjusting the test probes back and forth. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic structural diagram of the first surface of a solar cell according to a preferred embodiment of the present invention;

[0024] Figure 2 yes Figure 1 Enlarged view of area A in the middle;

[0025] Figure 3 yes Figure 1 Schematic diagram of a strip-shaped battery module formed by slicing a solar cell;

[0026] Figure 4 is a structural schematic diagram of the first surface of a solar cell according to another preferred embodiment of the present invention;

[0027] Figure 5 yes Figure 4 Enlarged view of area B in the middle;

[0028] Figure 6 yes Figure 5 Schematic diagram of a strip-shaped battery module formed by slicing a solar cell;

[0029] Figure 7 This is a schematic structural diagram of the second surface of a solar cell according to another preferred embodiment of the present invention;

[0030] Figure 8 yes Figure 7 Enlarged view of area C in the middle;

[0031] Figure 9 yes Figure 7 Schematic diagram of a strip-shaped battery module formed by slicing a solar cell;

[0032] Figure 10 yes Figure 9 Enlarged view of area D in the middle;

[0033] Figure 11 This is a schematic structural diagram of the second surface of a solar cell according to another preferred embodiment of the present invention;

[0034] Figure 12 yes Figure 1 ,or Figure 4 ,or Figure 7 ,or Figure 11 Schematic diagram of the test of solar cells before cutting.

[0035] Among them, 100-solar cell, 1-first electrode pattern, 11-first main grid, 111-first narrow main grid segment, 112-first wide main grid segment, 113-first straight-through electrode, 12-first fine grid, 2-first silver interconnect electrode, 3-second electrode pattern, 31-second main grid, 311-second straight-through electrode, 32-test electrode, 321-test electrode block, 33-grid line back electric field, 331-busbar main grid, 332-fine grid, 4-second silver interconnect electrode, 41-silver electrode block, 42-grid line group, 5-strip battery module, 6-probe, 7-division area. Specific embodiments

[0036] The present invention will be described in detail below with reference to the specific embodiments shown in the accompanying drawings. However, these embodiments do not limit the present invention, and any structural, methodological, or functional changes made by those skilled in the art based on these embodiments are all within the scope of protection of the present invention.

[0037] In the various drawings of the present invention, for the sake of convenience, some sizes of structures or parts are exaggerated relative to other structures or parts, and thus, only the basic structure of the subject matter of the present invention is illustrated.

[0038] Please refer to Figures 1-2 、 Figures 4-5 、 Figures 7-8 and Figures 11-12 As shown, the solar cell 100 of the present invention includes a plurality of strip-shaped battery areas arranged at intervals along a first direction, and a dividing area 7 located between adjacent strip-shaped battery areas. The strip-shaped battery areas include a first electrode pattern 1 located on the first surface and a second electrode pattern 3 located on the second surface. After the dividing area 7 is cut, each strip-shaped battery area forms a strip-shaped battery module 5.

[0039] Alternatively, the solar cell 100 may be described as comprising a plurality of first electrode patterns 1 spaced apart along a first direction on a first surface, a partitioning region 7 located between adjacent first electrode patterns 1, and second electrode patterns 3 located on a second surface and corresponding one-to-one with the first electrode patterns 1. After slicing the partitioning region 7, a plurality of strip-shaped battery modules 5 are formed, each of which has the first electrode pattern 1 on the first surface and the second electrode pattern 3 on the second surface.

[0040] Specifically, the first electrode pattern 1 includes a first main grid 11 located at one edge of the strip battery area, and the second electrode pattern 3 includes a second main grid 31 and a test electrode 32 located at two opposite edges respectively; the first main grid 11 and the second main grid 31 are respectively arranged at two opposite edges of the strip battery area, and the test electrode 32 and the first main grid 11 are distributed on the same edge of the strip battery area and are arranged correspondingly up and down; therefore, upper and lower probes 6 can be used for testing, which is closer to the performance of the strip battery module 5 formed after slicing; and the same test probe 6 can be used as the traditional whole solar cell 100, eliminating the process of adjusting the test probe 6 back and forth.

[0041] Specifically, the first busbar 11 includes alternating first narrow busbar segments 111 and first wide busbar segments 112, and the test electrode 32 includes test electrode blocks 321 corresponding one-to-one to the plurality of first wide busbar segments 112. Alternatively, the first busbar 11 is a first through-type electrode 113, and the test electrode 32 includes a plurality of test electrode blocks 321 corresponding to different positions of the first through-type electrode 113, thereby saving slurry.

[0042] In a preferred embodiment, the first surface is the front surface, the second surface is the back surface, and the test electrode 32 is located on the back surface rather than the front surface where light absorption is greater. This can reduce the impact on light absorption to a certain extent and has less impact on the aesthetics of the final photovoltaic module.

[0043] At this time, the second electrode pattern 3 also includes a grid-line back field 33 located on its second surface. The grid-line back field 33 includes a busbar 331 and a fine grid 332 located on one side of the busbar 331. The fine grid 332 includes a portion of grid lines perpendicular to the busbar 331 and an anti-break grid parallel to the busbar 331 and connected to the aforementioned portion of grid lines. Compared to traditional designs where the entire second surface is provided with a single back field, the grid-line back field 33 significantly reduces the light-shielding area of ​​the second surface, increases the light-receiving area of ​​the second surface, and improves conversion efficiency.

[0044] At least a portion of the second busbar 31 is connected to the busbar 331, preferably in an overlapping manner. This means that the projections of the second busbar 31 and the busbar 331 partially overlap in a direction perpendicular to the strip-shaped cell region. This ensures a more stable electrical connection and facilitates fabrication. Current is collected by several fine grids 332 and then flows to the busbar 331. From there, the current flows to the second busbar 31, forming a shingled assembly. The second busbar 31 then electrically connects to the first busbar 11 of the adjacent strip-shaped cell region, enabling current output from the strip-shaped cell region.

[0045] Preferably, a portion of the busbar 331 is located between the second busbar 31 and the fine grids 332 to enhance current transmission. This portion of the busbar 331 can be connected to most or all of the fine grids 332. Therefore, current can be directly collected by the fine grids 332 to the busbar 331, and then returned from the busbar 331 to the second busbar 31, improving current collection. Furthermore, since the closer the busbar is to the second busbar 31, the higher the current density, the more consistent the current density per unit area, reducing reliability risks caused by uneven current density. This effectively addresses current loss caused by partial grid breakage.

[0046] The test electrode 32 is electrically connected to part of the fine grid 332, preferably in an overlapping connection, that is, the projections of the test electrode 32 and part of the fine grid 332 partially overlap along the direction perpendicular to the strip battery area; this makes the electrical connection more stable and easier to implement in the manufacturing process.

[0047] Furthermore, based on any of the above-mentioned solar cell 100, it also includes a first silver interconnect electrode 2 spanning the dividing area 7 of the first surface, the first silver interconnect electrode 2 electrically connecting the first electrode pattern 1 of the two adjacent strip-shaped battery areas; a second silver interconnect electrode 4 located in the dividing area 7 of the second surface, the second silver interconnect electrode 4 electrically connecting the second electrode pattern 3 of the two adjacent strip-shaped battery areas; so that a certain connection is maintained between the small pieces before cutting, the voltage of each small piece and the current density of the entire battery are balanced, and abnormal test results caused by differences in electrical performance between the small pieces are prevented, thereby improving the stability of the test, while ensuring the uniformity of the brightness of the EL image and reducing the probability of EL judgment errors.

[0048] In addition, the first silver interconnect electrode 2 and the second silver interconnect electrode 4 are formed by silver paste printing, so that the dividing area 7 of the solar cell 100 does not contain aluminum. When laser scribing is performed on the second surface, on the one hand, the depth of the laser scribing caused by the thicker back electric field absorbing the laser energy can be avoided, thereby improving the process reliability of the component; on the other hand, the small cracks caused by laser cutting to aluminum and aluminum-silicon alloy can be reduced, and the ability to resist mechanical loads can be increased; it can also avoid the heat during laser scribing vaporizing aluminum and then vaporizing silicon, and the phenomenon that part of the aluminum is accumulated at the incision during the vaporization process. Furthermore, after the shingled component is formed, there is no accumulated aluminum at the incision, so tip discharge will not occur, and burn-through will not occur during long-term use.

[0049] Specifically, the width of the second silver interconnect electrode 4 along the first direction is between 0.3 mm and 2 mm. During normal slicing, even when the slices are cut obliquely, the anti-breakage grid on one side of the dividing area 7 is not damaged, thereby ensuring the integrity of the grid-line-shaped back electric field 33 of the formed strip-shaped battery module 5 and ensuring effective current transmission.

[0050] In addition, in the embodiment where the first surface is the front surface, the first electrode pattern 1 further includes a first fine grid 12 located on one side of the first main grid 11 and perpendicular to the first main grid 11 .

[0051] In a specific embodiment, the root portion where the first fine gate 12 is connected to the first main gate 11 is wider than other portions of the first fine gate 12 . Combined with the characteristic that the closer to the first main gate 11 the higher the current density, the current density per unit area can be ensured to be consistent, thereby reducing the reliability risk caused by uneven current density.

[0052] The first silver interconnect electrode 2 is a plurality of silver grid lines, which connect 5%-50% of the first fine grids 12 in the first electrode pattern 1 with the adjacent first electrode pattern 1; since only part of the first fine grids 12 are electrically connected to the adjacent first electrode pattern 1, the remaining fine grids are not connected, thereby maintaining the relative independence of the electrical performance of the small-piece battery, making its test results closer to its performance in the photovoltaic module, and making the test more accurate.

[0053] The second surface is the back surface, and the second silver interconnect electrode 4 includes a plurality of silver electrode blocks 41 or a plurality of grid line groups 42 arranged at intervals, which can save slurry while maintaining the relative independence of the electrical performance of the small-chip battery.

[0054] Furthermore, the second busbar 31 includes alternating second narrow busbar segments and second wide busbar segments, with a plurality of silver electrode blocks 41 connected one-to-one with the plurality of second wide busbar segments, or a plurality of gate line groups 42 connected one-to-one with the plurality of second wide busbar segments. Alternatively, the second busbar 31 is a second through-type electrode 311, with a plurality of silver electrode blocks 41 or a plurality of gate line groups 42 connected to the second through-type electrode 311.

[0055] After slicing along the dotted line in the dividing area 7, a number of strip-shaped battery modules 5 are formed, such as Figure 3 、 Figure 6 、 Figure 9 and Figure 10 As shown, each of the strip-shaped battery modules 5 has the first electrode pattern 1 on the first surface and the second electrode pattern 3 on the second surface.

[0056] Specifically, the present invention further provides a strip-shaped battery module 5 having the same electrode pattern as the strip-shaped battery region. Those skilled in the art will appreciate that the strip-shaped battery module 5 can be formed by laser cutting the solar cell 100 or by forming a single piece.

[0057] The strip battery module 5 includes a first main grid 11 located on the first surface, a second main grid 31 located on the second surface, and a test electrode 32. The first main grid 11 and the second main grid 31 are respectively arranged at two opposite edges of the strip battery module 5. The test electrode 32 and the first main grid 11 are distributed on the same edge of the strip battery module 5 and are arranged correspondingly up and down. Therefore, upper and lower probes 6 can be used for testing, which is closer to the performance of the strip battery module 5 formed after slicing. The same test probe 6 can be used as the traditional whole solar cell 100, eliminating the process of adjusting the test probe 6 back and forth.

[0058] Other structures and their purposes will not be described in detail here.

[0059] In addition, the present invention further provides a photovoltaic module (not shown), comprising the above strip-shaped battery modules 5 , wherein two adjacent strip-shaped battery modules 5 are connected by overlapping at their edges with conductive adhesive.

[0060] In summary, the present invention sets the test electrode 32, and the upper and lower probes 6 can be used for testing, which is closer to the performance of the strip battery module 5 formed after slicing; and the same test probe 6 can be used as the traditional whole solar cell 100, eliminating the process of adjusting the test probe 6 back and forth.

[0061] It should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each implementation method can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0062] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the present invention. They are not intended to limit the scope of protection of the present invention. Any equivalent implementation methods or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A strip-shaped battery module, comprising a first busbar located on a first surface and a second busbar located on a second surface, wherein the first busbar and the second busbar are respectively arranged at two opposite edges of the strip-shaped battery module, characterized in that: The strip battery module also includes a test electrode located on the second surface, and the test electrode and the first main grid are distributed on the same edge of the strip battery module and are arranged correspondingly above and below; the first surface is the front side, and the second surface is the back side; the strip battery module also includes a grid line-shaped back electric field located on the second surface, and the grid line-shaped back electric field includes a bus bar and a fine grid, and some or all of the fine grids are connected to the bus bar, and the test electrode is electrically connected to some of the fine grids.

2. The strip-shaped battery module according to claim 1, wherein: The first main gate includes alternately arranged first narrow main gate segments and first wide main gate segments, and the test electrode includes test electrode blocks corresponding to a plurality of first wide main gate segments.

3. The strip-shaped battery module according to claim 1, wherein: The first main grid is a first through-type electrode, and the test electrode includes a plurality of test electrode blocks corresponding to different positions of the first through-type electrode.

4. The strip-shaped battery module according to claim 1, wherein: The fine grid is located on one side of the bus bar, and at least a portion of the second bus bar is connected to the bus bar.

5. A solar cell comprising a plurality of strip-shaped battery regions spaced apart along a first direction and a partitioning region between adjacent strip-shaped battery regions, wherein the strip-shaped battery regions include a first busbar located on a first surface and a second busbar located on a second surface, wherein the first busbar and the second busbar are respectively disposed at two opposite edges of the strip-shaped battery regions, characterized in that : The strip battery area also includes a test electrode located on the second surface, and the test electrode and the first main grid are distributed on the same edge of the strip battery area and are arranged correspondingly above and below; the first surface is the front surface, and the second surface is the back surface; the strip battery area also includes a grid line-shaped back electric field located on the second surface, and the grid line-shaped back electric field includes a bus bar and a fine grid, and some or all of the fine grids are connected to the bus bar, and the test electrode is electrically connected to some of the fine grids.

6. The solar cell according to claim 5, wherein: The first main gate includes first narrow main gate segments and first wide main gate segments that are alternately arranged, and the test electrode includes test electrode blocks corresponding to a plurality of first wide main gate segments on a one-to-one basis.

7. The solar cell according to claim 5, wherein: The first main grid is a first through-type electrode, and the test electrode includes a plurality of test electrode blocks corresponding to different positions of the first through-type electrode.

8. The solar cell according to claim 5, wherein: The fine grid is located on one side of the bus bar, and at least a portion of the second bus bar is connected to the bus bar.

9. The solar cell according to any one of claims 5 to 8, characterized in that: It also includes a first silver interconnect electrode located in the dividing area of ​​the first surface, the first silver interconnect electrode electrically connecting the first electrode pattern of the two adjacent strip battery areas; and a second silver interconnect electrode located in the dividing area of ​​the second surface, the second silver interconnect electrode electrically connecting the second electrode pattern of the two adjacent strip battery areas.

10. The solar cell according to claim 9, wherein: The width of the second silver interconnecting electrodes along the first direction is between 0.3 mm and 2 mm.

11. The solar cell according to claim 9, wherein: The first surface is the front side, the first electrode pattern also includes a first fine grid vertically connected to the first main grid on one side of the first main grid, the first silver interconnect electrode is a plurality of silver grid lines, and the plurality of silver grid lines connect 5%-50% of the first fine grids in the first electrode pattern with adjacent first electrode patterns.

12. The solar cell according to claim 9, wherein: The second surface is the back surface, and the second silver interconnection electrode includes a plurality of silver electrode blocks or a plurality of grid line groups arranged at intervals.

13. The solar cell according to claim 12, wherein: The second main gate includes alternately arranged second narrow main gate segments and second wide main gate segments, a plurality of silver electrode blocks are connected one-to-one with the plurality of second wide main gate segments, or a plurality of gate line groups are connected one-to-one with the plurality of second wide main gate segments; Alternatively, the second main grid is a second through-type electrode, and a plurality of silver electrode blocks or a plurality of gate line groups are all connected to the second through-type electrode.

14. A photovoltaic module comprising the strip-shaped battery module according to any one of claims 1 to 4, wherein two adjacent strip-shaped battery modules are connected by overlapping their edges.

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