A battery string

Abstract

This application is applicable to the technical field of solar cells and provides a battery string. The battery string includes at least two solar cells, each of which includes a first electrode and a second electrode with a polarity opposite to that of the first electrode; and a solder ribbon respectively connecting the first solar cell and the second solar cell adjacent to the first solar cell. The solder ribbon includes a first contact area, a second contact area, and a connection area; the first contact area is used to connect the first solar cell, the second contact area is used to connect the second solar cell, and the connection area is used to connect the first contact area and the second contact area; the shapes of the first contact area and the second contact area are different; and / or, the centerlines of at least one group of adjacent first contact areas and second contact areas are offset in the width direction of the connection area. In this way, the telescopic stress can be better absorbed through the deformation of the solder ribbon, thereby minimizing the damage to the solar cells caused by the stress.

Description

Technical Field

[0001] This application belongs to the technical field of solar cells, and particularly relates to a battery string. Background Art

[0002] Solar cells generate electricity by using the photovoltaic effect of semiconductor p-n junctions to convert sunlight into electrical energy, which is a source of sustainable clean energy.

[0003] Related technologies usually use solder tapes to connect multiple solar cells into a battery string, and then encapsulate them into a battery module through processes such as laying and lamination. However, the thermal mismatch between the solder tape and the solar cell, that is, the different proportional coefficients of thermal expansion and contraction with temperature changes, causes excessive stress between the solar cell and the solder tape, resulting in cracking and fragmentation of the solar cell. The thermal expansion and contraction of the solder tape also causes the solar cell to be subjected to the expansion and contraction stress of the solder tape, resulting in cracking and fragmentation of the solar cell.

[0004] Based on this, how to reduce the stress damage to the solar cells in the battery string has become an urgent problem to be solved. Summary of the Invention

[0005] This application provides a battery string, aiming to solve the problem of how to reduce the stress damage to the solar cells in the battery string.

[0006] In a first aspect, the battery string provided by this application includes:

[0007] At least two solar cells, each of the solar cells includes a first electrode and a second electrode with a polarity opposite to that of the first electrode; and

[0008] Solder tapes respectively connecting the first solar cell and the second solar cell adjacent to the first solar cell, the solder tape includes a first contact area, a second contact area and a connection area;

[0009] The first contact area is used to connect the first solar cell, the second contact area is used to connect the second solar cell, and the connection area is used to connect the first contact area and the second contact area;

[0010] The shapes of the first contact area and the second contact area are different; and / or, the centerlines of at least one group of adjacent first contact areas and second contact areas are offset in the width direction of the connection area.

[0011] Optionally, the first solar cell is provided with a first pad point and a second pad point, the first pad point connects the first electrode of the first solar cell, and the second pad point connects the second electrode of the first solar cell; the connection line between the first pad point and the second pad point closest to the first pad point forms a first angle with the length direction of the solder tape;

[0012] The second solar cell is provided with a third pad point and a fourth pad point. The third pad point is connected to the third electrode of the second solar cell, and the fourth pad point is connected to the fourth electrode of the second solar cell. The connection line between the third pad point and the fourth pad point closest to the third pad point forms a second angle with the length direction of the solder strip.

[0013] Optionally, 70° < α < 90°, 70° < β < 90°;

[0014] Wherein, α is the first angle and β is the second angle.

[0015] Optionally, the first solar cell is provided with a first pad point and a second pad point. The first pad point is connected to the first electrode of the first solar cell, and the second pad point is connected to the second electrode of the first solar cell. The second solar cell is provided with a third pad point and a fourth pad point. The third pad point is connected to the third electrode of the second solar cell, and the fourth pad point is connected to the fourth electrode of the second solar cell.

[0016] The solder strip connects the first pad point and the fourth pad point. The connection line between the first pad point and the fourth pad point closest to the first pad point forms a third angle with the length direction of the solder strip.

[0017] Optionally, 20° < γ < 60°;

[0018] Wherein, γ is the third angle.

[0019] Optionally, the connection area is provided with a gap, and one end of the gap forms an opening in the connection area.

[0020] Optionally, each first contact area corresponds to a group of the gaps. As the distance in the length direction from the corresponding first contact area increases, the distance in the width direction between a group of the gaps and the corresponding first contact area also increases.

[0021] And / or, each second contact area corresponds to a group of the gaps. As the distance in the length direction from the corresponding second contact area increases, the distance in the width direction between a group of the gaps and the corresponding second contact area also increases.

[0022] Optionally, a group of the gaps includes a first gap, a second gap, a third gap, a fourth gap, and a fifth gap. The first gap is located at the middle position of the group of the gaps, and the second gap and the third gap are respectively located on both sides of the first gap. The fourth gap is located on the side of the second gap away from the first gap, and the fifth gap is located on the side of the third gap away from the first gap.

[0023] The lengths of a group of said gaps satisfy the following relationship:

[0024] L1>L2=L3>L4=L5;

[0025] Wherein, L1 is the length of the first gap, L2 is the length of the second gap, L3 is the length of the third gap, L4 is the length of the fourth gap, and L5 is the length of the fifth gap.

[0026] Optionally, the solder strip connects the first solar cell and the second solar cell, and the connection area includes a first connection portion covering the first solar cell, a second connection portion covering the second solar cell, and a third connection portion covering the gap between the first solar cell and the second solar cell;

[0027] The size of the solder strip satisfies the following relationship:

[0028] d1 = L2, and / or, d1 = L3;

[0029] Wherein, d1 is the width of the first connection portion, L2 is the length of the second gap, and L3 is the length of the third gap.

[0030] Optionally, the distance between two adjacent gaps in a group of said gaps satisfies the following relationship:

[0031] 0.2 < L1 / (S1 + S2) < 1.5;

[0032] Wherein, L1 is the length of the first gap, S1 is the distance between the first gap and the second gap, and S2 is the distance between the second gap and the fourth gap;

[0033] and / or, 0.2 < L1 / (S3 + S4) < 1.5;

[0034] Wherein, L1 is the length of the first gap, S3 is the distance between the first gap and the third gap, and S4 is the distance between the third gap and the fifth gap.

[0035] Optionally, each of the first contact areas corresponds to a group of said gaps. As the distance in the length direction from the corresponding first contact area increases, the distance in the width direction between the group of gaps and the corresponding first contact area decreases;

[0036] and / or, each of the second contact areas corresponds to a group of said gaps. As the distance in the length direction from the corresponding second contact area increases, the distance in the width direction between the group of gaps and the corresponding second contact area decreases.

[0037] Optionally, each of the first contact areas corresponds to a group of the slits, and the distance between two adjacent slits in a group of the slits is equal;

[0038] And / or, each of the second contact areas corresponds to a group of the slits, and the distance between two adjacent slits in a group of the slits is equal.

[0039] Optionally, the number of the slits is multiple, and the extending directions of the multiple slits are all parallel to the width direction of the connection area.

[0040] Optionally, the width of the slit is 0.2 mm - 0.6 mm.

[0041] Optionally, in the same group of the slits, the distance between two adjacent slits is 1.5 mm - 4 mm.

[0042] Optionally, the distance between two adjacent groups of the slits is 1.5 mm - 15 mm.

[0043] Optionally, the connection area is further provided with through holes, and the other ends of the slits are communicated with the through holes.

[0044] Optionally, the first contact area is connected to a first solar cell, the second contact area is connected to a second solar cell, the through hole is oval, the length of the minor axis of the through hole is the width of the gap between the first solar cell and the second solar cell, and the major axis of the through hole coincides with the center line of the connection area.

[0045] Optionally, the through hole is oval, circular, semi-circular, or diamond-shaped.

[0046] Optionally, in a group of the through holes corresponding to each of the first contact areas, two adjacent through holes are staggered in the length direction.

[0047] Optionally, the solder ribbon connects the first solar cell and the second solar cell, the first contact area connects the positive electrode of the first solar cell, the second contact area connects the negative electrode of the second solar cell, and the area of the first contact area is greater than or equal to the area of the second contact area; or, the first contact area connects the negative electrode of the first solar cell, the second contact area connects the positive electrode of the second solar cell, and the area of the second contact area is greater than or equal to the area of the first contact area.

[0048] Optionally, the width of the connection area is 2.3 mm - 6 mm.

[0049] Optionally, the distance between the adjacent first contact area and the second contact area in the width direction of the connection area is 5 mm - 15 mm.

[0050] Optionally, the thickness of the solder ribbon is 0.1 mm - 0.3 mm.

[0051] Optionally, the solder ribbon includes a copper substrate and a tin layer coated on the copper substrate; or, the solder ribbon includes an aluminum substrate and a tin layer coated on the aluminum substrate; or, the solder ribbon is an aluminum strip; or, the solder ribbon is a tin strip.

[0052] Optionally, a plurality of the first contact areas are evenly distributed at one side of the connection area along the length direction of the connection area;

[0053] and / or, a plurality of the second contact areas are evenly distributed at the other side of the connection area along the length direction of the connection area.

[0054] Optionally, the connection area is rectangular; or, the connection area is bent, and the first contact area and the second contact area are arranged at the bending angle.

[0055] Optionally, the first contact area is a right-angled rectangle, a rounded rectangle, a regular circle, a semi-circle, a trapezoid; and / or, the second contact area is a right-angled rectangle, a rounded rectangle, a regular circle, a semi-circle, a trapezoid.

[0056] In the solder ribbon of the embodiment of the present application, since a plurality of first contact areas and a plurality of second contact areas located on both sides of the connection area are staggered in the width direction of the connection area, and / or the shapes of the first contact area and the second contact area are different, the telescopic stress can be better absorbed through the deformation of the solder ribbon, and thus the damage to the battery cells caused by the stress can be minimized. Description of the Drawings

[0057] Figure 1 is a schematic structural diagram of a battery string according to an embodiment of the present application;

[0058] Figure 2 is a schematic diagram of a partial structure of the solder ribbon in a battery string according to an embodiment of the present application;

[0059] Figure 3 is a schematic structural diagram of the solder ribbon in a battery string according to an embodiment of the present application;

[0060] Figure 4 is a schematic structural diagram of the solder ribbon in a battery string according to an embodiment of the present application;

[0061] Figure 5 is a schematic structural diagram of the solder ribbon in a battery string according to an embodiment of the present application;

[0062] Figure 6 is a schematic structural diagram of the solder ribbon in a battery string according to an embodiment of the present application;

[0063] Figure 7 is a schematic diagram of a partial structure of the solder ribbon in a battery string according to an embodiment of the present application;

[0064] Figure 8 It is a schematic diagram of a partial structure of a welding ribbon in a battery string according to an embodiment of the present application;

[0065] Figure 9 It is a schematic diagram of a partial structure of a welding ribbon in a battery string according to an embodiment of the present application;

[0066] Main element symbol description:

[0067] Battery string 100, first battery cell 21, first pad point 211, second pad point 212, second battery cell 22, third pad point 221, fourth pad point 222;

[0068] Welding ribbon 10, connection area 101, center line 1001 of the connection area, first connection portion 1011, second connection portion 1012, third connection portion 1013; first contact area 11, center line 111 of the first contact area, second contact area 12, center line 121 of the second contact area, gap 13, first gap 131, second gap 132, third gap 133, fourth gap 134, fifth gap 135, through hole 14;

[0069] Width w0 of the connection area, width w1 of the gap, length L1 of the first gap, length L2 of the second gap, length L3 of the third gap, length L4 of the fourth gap, length L5 of the fifth gap, width d1 of the first connection portion, distance S0 between the adjacent first contact area and the second contact area in the width direction of the connection area, distance S1 between the first gap and the second gap, distance S2 between the second gap and the fourth gap, distance S3 between the first gap and the third gap, distance S4 between the third gap and the fifth gap, distance D1 between two adjacent groups of gaps. Detailed implementation manners

[0070] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. 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.

[0071] Please refer to Figure 1 、 Figure 2 and Figure 3 , the battery string 100 of the embodiment of the present application includes:

[0072] At least two battery cells, each battery cell includes a first electrode and a second electrode with a polarity opposite to that of the first electrode; and

[0073] A welding ribbon 10 respectively connecting the first battery cell 21 and the second battery cell 22 adjacent to the first battery cell 21, and the welding ribbon 10 includes a first contact area 11, a second contact area 12 and a connection area 101;

[0074] The first contact area 11 is used to connect the first solar cell 21, the second contact area 12 is used to connect the second solar cell 22, and the connection area 101 is used to connect the first contact area 11 and the second contact area 12;

[0075] The shapes of the first contact area 11 and the second contact area 12 are different; and / or, the centerlines of at least one group of adjacent first contact areas 11 and second contact areas 12 are offset in the width direction of the connection area 101.

[0076] In the battery string 100 according to the embodiment of the present application, since a plurality of first contact areas 11 and a plurality of second contact areas 12 located on both sides of the connection area 101 are offset in the width direction of the connection area 101, and / or the shapes of the first contact area 11 and the second contact area 12 are different, the welding tape 10 can better absorb the telescopic stress through deformation, and further minimize the damage of the stress to the solar cells.

[0077] It can be understood that the welding tape 10 absorbs the stress in the length direction, width direction and thickness direction through deformation.

[0078] Specifically, when the welding tape 10 is deformed, on the line segment formed by the connection of the adjacent first contact area 11 and the second contact area 12, the closer to the first contact area 11 or the second contact area 12, the greater the stress.

[0079] Specifically, the number of solar cells included in the battery string 100 may be 2, 3, 4 or other numbers. The first solar cell 21 and the second solar cell 22 refer to two adjacent solar cells in the battery string 100 connected by the welding tape 10. In Figure 1 In the example, the battery string 100 includes two solar cells, namely the first solar cell 21 and the second solar cell 22.

[0080] It can be understood that "each solar cell includes a first electrode and a second electrode with a polarity opposite to that of the first electrode" means that each solar cell includes a first electrode and a second electrode, one of the first electrode and the second electrode is a positive electrode, and the other of the first electrode and the second electrode is a negative electrode.

[0081] It can be understood that the different shapes of the solder joints on both sides or the offset of the centerlines can make the welding tape 10 asymmetric.

[0082] It can be understood that the dislocation of the solder joints on both sides of the connection area 101 results in a longer connection area 101 between the solder joints to absorb the stress deformation amount, and can better absorb the tensile deformation and the torsional deformation.

[0083] It can be understood that "the shapes of the first contact area 11 and the second contact area 12 are different; and / or, the center lines of at least one group of adjacent first contact areas 11 and second contact areas 12 are offset in the width direction of the connection area 101" includes three cases: the shapes of the first contact area 11 and the second contact area 12 are different, and the center lines of at least one group of adjacent first contact areas 11 and second contact areas 12 are offset in the width direction of the connection area 101; the shapes of the first contact area 11 and the second contact area 12 are different, and the center lines of all adjacent first contact areas 11 and second contact areas 12 coincide in the width direction of the connection area 101; the shapes of the first contact area 11 and the second contact area 12 are the same, and the center lines of at least one group of adjacent first contact areas 11 and second contact areas 12 are offset in the width direction of the connection area 101. In this article, the last case is taken as an example for explanation and illustration, but this does not represent a limitation on the above cases.

[0084] It can be understood that "the center lines of at least one group of adjacent first contact areas 11 and second contact areas 12 are offset in the width direction of the connection area 101" can mean that the center lines of one group of adjacent first contact areas 11 and second contact areas 12 are offset in the width direction of the connection area 101; it can mean that the center lines of multiple groups of adjacent first contact areas 11 and second contact areas 12 are offset in the width direction of the connection area 101, and the center lines of the remaining adjacent first contact areas 11 and second contact areas 12 coincide in the width direction of the connection area 101; it can mean that the center lines of all adjacent first contact areas 11 and second contact areas 12 are offset in the width direction of the connection area 101. In this article, the last case is taken as an example for explanation and illustration, but this does not represent a limitation on the above cases.

[0085] It can be understood that "being offset in the width direction of the connection area 101" means not overlapping in the width direction.

[0086] It can be understood that the center line 111 of the first contact area is a line passing through the center of the first contact area 11 and parallel to the width direction. The center line 121 of the second contact area 12 is a line passing through the center of the second contact area 12 and parallel to the width direction.

[0087] Please refer to Figure 3 , optionally, the first solar cell 21 is provided with a first pad point 211 and a second pad point 212. The first pad point 211 is connected to the first electrode of the first solar cell 21, and the second pad point 212 is connected to the second electrode of the first solar cell 21; the connection line between the first pad point 211 and the second pad point 212 closest to the first pad point 211 forms a first included angle α with the length direction of the solder tape 10.

[0088] In this way, the first pad points 211 and the second pad points 212 of the first solar cell 21 are staggered in the width direction, which is adapted to the two types of electrodes arranged alternately with the first solar cell 21, facilitating connection to the two types of electrodes respectively. At the same time, it is adapted to the two non-symmetrical contact areas of the solder tape 10, facilitating connection to the two contact areas of the two solder tapes 10 respectively. In this way, it is beneficial to improve production efficiency.

[0089] Specifically, 70° < α < 90°. For example, it is 71°, 75°, 82°, 83°, 85°, 89°.

[0090] In this way, the staggering degree between the first pad point 211 and the second pad point 212 is within a suitable range, avoiding the difficulty of connecting to the electrodes of the first solar cell 21 or the contact area of the solder tape 10 caused by too small or too large a staggering degree.

[0091] Preferably, α is 83°. In this way, the staggering degree between the first pad point 211 and the second pad point 212 is the most appropriate.

[0092] Specifically, in Figure 1 the example, the number of the first pad points 211 is 8. It can be understood that in other embodiments, the number of the first pad points 211 can be 1, 2, 3, 4 or other numbers. Similarly, in Figure 1 the example, the number of the second pad points 212 is 7. It can be understood that in other embodiments, the number of the second pad points 212 can be 1, 2, 3, 4 or other numbers.

[0093] Specifically, in Figure 1 the example, the shapes of the multiple first pad points 211 are the same. It can be understood that in other embodiments, the shapes of the multiple first pad points 211 can be different. Similarly, in Figure 1 the example, the shapes of the multiple second pad points 212 are the same. It can be understood that in other embodiments, the shapes of the multiple second pad points 212 can be different.

[0094] Specifically, in Figure 1 the example, the multiple first pad points 211 are all rectangular. It can be understood that in other embodiments, the first pad points 211 can be rounded rectangles, regular circles, semi-circles, trapezoids. Similarly, in Figure 1 the example, the multiple second pad points 212 are all rectangular. It can be understood that in other embodiments, the second pad points 212 can be rounded rectangles, regular circles, semi-circles, trapezoids.

[0095] Specifically, in Figure 1In the example, the orthographic projection of the first contact area 11 on the first solar cell 21 is located within the first pad point 211. In this way, it is convenient to align the contact area with the pad point, so as to facilitate welding the welding tape 10 to the first solar cell 21, which is beneficial to improving production efficiency.

[0096] It can be understood that in other embodiments, the orthographic projection of the first contact area 11 on the first solar cell 21 may partially overlap the first pad point 211 or cover the first pad point 211.

[0097] Please refer to Figure 3 , optionally, the second solar cell 22 is provided with a third pad point 221 and a fourth pad point 222. The third pad point 221 is connected to the third electrode of the second solar cell 22, and the fourth pad point 222 is connected to the fourth electrode of the second solar cell 22; the connection line between the third pad point 221 and the fourth pad point 222 closest to the third pad point 221 forms a second included angle β with the length direction of the welding tape 10.

[0098] In this way, the third pad point 221 and the fourth pad point 222 of the second solar cell 22 are staggered in the width direction, which is adapted to the two types of electrodes arranged alternately on the second solar cell 22, and is convenient for connecting to the two types of electrodes respectively. At the same time, it is adapted to the two non-symmetrical contact areas of the welding tape 10, and is convenient for connecting to the two contact areas of the two welding tapes 10 respectively. In this way, it is beneficial to improve production efficiency.

[0099] Specifically, 70° < β < 90°. For example, it is 71°, 75°, 82°, 83°, 85°, 89°.

[0100] In this way, the staggering degree of the third pad point 221 and the fourth pad point 222 is within a suitable range, avoiding the difficulty of connecting to the electrodes of the second solar cell 22 or the contact area of the welding tape 10 caused by too small or too large staggering degree.

[0101] Preferably, β is 83°. In this way, the staggering degree between the first pad point 211 and the second pad point 212 is the most appropriate.

[0102] Specifically, in Figure 1 the example, the number of the third pad points 221 is 8. It can be understood that in other embodiments, the number of the third pad points 221 can be 1, 2, 3, 4 or other numbers. Similarly, in Figure 1 the example, the number of the fourth pad points 222 is 7. It can be understood that in other embodiments, the number of the fourth pad points 222 can be 1, 2, 3, 4 or other numbers.

[0103] Specifically, in Figure 1In the example, the shapes of multiple third pad points 221 are the same. It can be understood that in other embodiments, the shapes of multiple third pad points 221 can be different. Similarly, in Figure 1 the example, the shapes of multiple fourth pad points 222 are the same. It can be understood that in other embodiments, the shapes of multiple fourth pad points 222 can be different.

[0104] Specifically, in Figure 1 the example, multiple third pad points 221 are all rectangular. It can be understood that in other embodiments, the third pad points 221 can be rounded rectangles, regular circles, semi - circles, trapezoids. Similarly, in Figure 1 the example, multiple fourth pad points 222 are all rectangular. It can be understood that in other embodiments, the fourth pad points 222 can be rounded rectangles, regular circles, semi - circles, trapezoids.

[0105] Specifically, in Figure 1 the example, the orthographic projection of the second contact area 12 on the second solar cell 22 is located within the third pad point 221. In this way, it is convenient for the alignment of the contact area and the pad point, so as to facilitate welding the welding tape 10 to the second solar cell 22, which is beneficial to improving production efficiency.

[0106] It can be understood that in other embodiments, the orthographic projection of the second contact area 12 on the second solar cell 22 can partially overlap with the third pad point 221 or cover the third pad point 221.

[0107] Please refer to Figure 1 . Optionally, the first solar cell 21 is provided with a first pad point 211 and a second pad point 212. The first pad point 211 is connected to the first electrode of the first solar cell 21, and the second pad point 212 is connected to the second electrode of the first solar cell 21; the second solar cell 22 is provided with a third pad point 221 and a fourth pad point 222. The third pad point 221 is connected to the third electrode of the second solar cell 22, and the fourth pad point 222 is connected to the fourth electrode of the second solar cell 22; the welding tape is connected to the first pad point 211 and the fourth pad point 222, and the connection line between the first pad point 211 and the fourth pad point 222 closest to the first pad point 211 forms a third angle γ with the length direction of the welding tape 10.

[0108] In this way, the first pad point 211 of the first solar cell 21 and the fourth pad point 222 of the second solar cell 22 are staggered in the width direction, which is adapted to the two asymmetric contact areas of the welding tape 10, facilitating connection to the two contact areas of the same welding tape 10 respectively, being beneficial to improving production efficiency, and also being beneficial to better absorbing the expansion and contraction stress through the deformation of the welding tape 10, thereby minimizing the damage of the stress to the solar cell.

[0109] Specifically, 20° < γ < 60°. 21°, 23°, 30°, 32°, 35°, 39°, 40°, 45°, 50°, 55°, 59°.

[0110] In this way, the degree of misalignment between the first pad point 211 and the fourth pad point 222 is within a suitable range, avoiding the difficulty in connecting to the contact area of the solder strip 10 caused by too small or too large a degree of misalignment.

[0111] Furthermore, 20° < γ < 40°. For example, it is 21°, 23°, 30°, 32°, 35°, 39°.

[0112] Preferably, γ is 23°. In this way, the degree of misalignment between the first pad point 211 and the fourth pad point 222 is the most suitable.

[0113] Please refer to Figure 3 , optionally, the thickness of the solder strip 10 is 0.1 mm - 0.3 mm. For example, it is 0.1 mm, 0.12 mm, 0.14 mm, 0.18 mm, 0.2 mm, 0.21 mm, 0.25 mm, 0.27 mm, 0.3 mm. In this way, the thickness of the solder strip 10 is within a suitable range, avoiding the poor effect of the solder strip 10 absorbing the expansion and contraction stress or the poor mechanical strength caused by too small a thickness, and also avoiding the high cost of the solder strip 10 caused by too large a thickness of the solder strip 10.

[0114] Preferably, the thickness of the solder strip 10 is 0.14 mm. In this way, considering the effects of the solder strip 10 absorbing the expansion and contraction stress, mechanical strength and cost, the overall effect is the best.

[0115] Please refer to Figure 3 , optionally, the solder strip 10 includes a copper substrate and a tin layer coated on the copper substrate. In this way, the solder strip 10 has good electrical conductivity, resulting in a good effect of electrically connecting the battery cells.

[0116] Specifically, the hardness range of the solder strip 10 is 40 HV - 60 HV. For example, it is 40 HV, 42 HV, 45 HV, 48 HV, 50 HV, 53 HV, 55 HV, 59 HV, 60 HV. In this way, the solder strip 10 has good mechanical strength.

[0117] Specifically, the uniformity of the tin layer is ±10%. For example, it is -10%, -8%, -5%, -2%, 0%, 1%, 5%, 7%, 10%. In this way, the solder strip 10 has good electrical conductivity.

[0118] Specifically, the thickness of the tin layer is 6 μm - 10 μm. For example, it is 6 μm, 6.2 μm, 7 μm, 7.5 μm, 8 μm, 9 μm, 10 μm.

[0119] In other embodiments, the solder strip 10 may also include an aluminum substrate and a tin layer coated on the aluminum substrate; or, the solder strip 10 is an aluminum strip; or, the solder strip 10 is a tin strip.

[0120] Optionally, the elongation rate of the solder strip 10 ≥ 25%. For example, it is 25%, 27%, 30%, 35%.

[0121] Please refer to Figure 3 , optionally, the connection area 101 is rectangular. In this way, the shape of the connection area 101 is relatively regular and convenient for manufacturing.

[0122] Please refer to Figure 4 , optionally, the connection area 101 is bent, and the first contact area 11 and the second contact area 12 are arranged at the bending angle. In this way, the stress on the solar cell is reduced through the bent connection area 101, thereby reducing the damage to the solar cell. At the same time, the bending angle can also assist in positioning the first contact area 11 and the second contact area 12, which is beneficial to improving the manufacturing efficiency. Further, the bending angle is an obtuse angle. In this way, the angle of the bending angle is relatively large, which can further reduce the stress on the solar cell. Further, each bending angle is provided with a first contact area 11 or a second contact area 12.

[0123] It can be understood that in other embodiments, the connection area 101 may be alternately connected by a rectangle and a bent shape, or may be other shapes; in other embodiments, the bending angle may be an acute angle, the bending angle may be a right angle, the bending angle may be an arc angle, or may be at least two of an acute angle, a right angle, an obtuse angle, and an arc angle; in other embodiments, some of the bending angles may be provided with a first contact area 11 or a second contact area 12, and the remaining bending angles are not provided with a first contact area 11 and a second contact area 12.

[0124] Please refer to Figure 3 , optionally, the width w0 of the connection area 101 is 2.3 mm - 6 mm. For example, it is 2.3 mm, 2.4 mm, 2.8 mm, 3 mm, 3.35 mm, 3.5 mm, 4 mm, 4.6 mm, 5 mm, 5.8 mm, 6 mm. In this way, the width w0 of the connection area 101 is within a suitable range, which can avoid the poor effect of the solder strip 10 absorbing the expansion and contraction stress or the difficulty of connecting the solder strip 10 to the solar cell due to the too small width w0 of the connection area 101, and can also avoid the high cost of the solder strip 10 due to the too large width w0 of the connection area 101. The tolerance of the width w0 of the connection area 101 may be ±0.1 mm.

[0125] Preferably, the width w0 of the connection area 101 is 3.35 mm. In this way, considering the effect of the solder strip 10 absorbing the expansion and contraction stress, realizing the connection of the solar cell and the cost, the overall effect is the best.

[0126] Please refer to Figure 3, optionally, the length L0 of the connection area 101 is 170 mm - 220 mm. For example, it is 170 mm, 176 mm, 180 mm, 182 mm, 210 mm, 218 mm, 220 mm. The tolerance of the length L0 of the connection area 101 can be ±0.1 mm.

[0127] Preferably, the length L0 of the connection area 101 is 176 mm.

[0128] Please refer to Figure 3 , optionally, each first contact area 11 extends outward from one side of the connection area 101 along the width direction of the connection area 101. Each second contact area 12 extends outward from the other side of the connection area 101 along the width direction of the connection area 101. In this way, the settings of the first contact area 11 and the second contact area 12 are relatively regular, which is convenient for manufacturing.

[0129] It can be understood that in other embodiments, the direction in which each first contact area 11 extends outward from one side of the connection area 101 can form an acute angle or an obtuse angle with the width direction of the connection area 101; some of the first contact areas 11 can extend outward from one side of the connection area 101 along the width direction of the connection area 101, and the rest of the first contact areas 11 can extend outward from one side of the connection area 101 in a direction that forms an acute angle or an obtuse angle with the width direction of the connection area 101; the direction in which each second contact area 12 extends outward from one side of the connection area 101 can form an acute angle or an obtuse angle with the width direction of the connection area 101; some of the second contact areas 12 can extend outward from one side of the connection area 101 along the width direction of the connection area 101, and the rest of the second contact areas 12 can extend outward from one side of the connection area 101 in a direction that forms an acute angle or an obtuse angle with the width direction of the connection area 101. Specifically, when the multiple first contact areas 11 form an acute angle or an obtuse angle with the width direction of the connection area 101, the angles formed by the multiple first contact areas 11 can be the same or different; when the multiple second contact areas 12 form an acute angle or an obtuse angle with the width direction of the connection area 101, the angles formed by the multiple second contact areas 12 can be the same or different.

[0130] Please refer to Figure 3 , optionally, the multiple first contact areas 11 are equally spaced along the length direction of the connection area 101 on one side of the connection area 101. Optionally, the multiple second contact areas 12 are equally spaced along the length direction of the connection area 101 on the other side of the connection area 101. In this way, the connection area 101 between each section of the first contact area 11 and the second contact area 12 has the same ability to absorb telescopic stress, which is beneficial to further reducing the damage to the battery chip. At the same time, the arrangement of the solder joints is relatively regular, which is convenient for manufacturing and also convenient for ensuring that the center lines of adjacent solder joints are staggered.

[0131] In other embodiments, the distances between adjacent first contact regions 11 may all be different; the distances between some adjacent first contact regions 11 may be the same, while the distances between the remaining adjacent first contact regions 11 are different; similarly, the distances between adjacent second contact regions 12 may all be different; the distances between some adjacent second contact regions 12 may be the same, while the distances between the remaining adjacent second contact regions 12 are different. The specific arrangement pattern of the solder joints is not limited herein.

[0132] Please refer to Figure 3 , optionally, the distance S0 between the adjacent first contact region 11 and the second contact region 12 in the width direction of the connection region 101 is 5 mm - 15 mm. For example, it is 5 mm, 5.5 mm, 8 mm, 10 mm, 11.375 mm, 13 mm, 15 mm. In this way, S0 is within a suitable range, avoiding poor deformation ability caused by too large or too small S0, thereby resulting in a poor effect of absorbing expansion and contraction stress, which is beneficial to reducing the damage of stress to the battery chip. The tolerance of the distance S0 can be ±0.02.

[0133] Preferably, the distance S0 between the adjacent first contact region 11 and the second contact region 12 in the width direction of the connection region 101 is 11.375 mm. In this way, the effect of reducing the damage of stress to the battery chip is the best.

[0134] Optionally, the first contact region 11 is in the shape of a right-angled rectangle, a rounded rectangle, a regular circle, a semi-circle, or a trapezoid. Optionally, the second contact region 12 is in the shape of a right-angled rectangle, a rounded rectangle, a regular circle, a semi-circle, or a trapezoid.

[0135] Specifically, in the Figure 3 example, multiple first contact regions 11 and multiple second contact regions 12 are all in the shape of rounded rectangles. Further, the radius of the chamfer is 0.2 mm - 0.4 mm. For example, it is 0.2 mm, 0.22 mm, 0.25 mm, 0.28 mm, 0.3 mm, 0.31 mm, 0.35 mm, 0.39 mm, 0.4 mm. Preferably, the radius of the chamfer is 0.3 mm.

[0136] It can be understood that in other examples, the shapes of the first contact region 11 and the second contact region 12 can also be different; the shapes of some first contact regions 11 can be the same, different from the shapes of the remaining first contact regions 11, or the shapes of all first contact regions 11 can be different; the shapes of some second contact regions 12 can be the same, different from the shapes of the remaining second contact regions 12, or the shapes of all second contact regions 12 can be different.

[0137] Optionally, the length of the first contact area 11 extending from the connection area 101 is 1.5 mm - 1.7 mm. For example, it is 1.5 mm, 1.52 mm, 1.55 mm, 1.6 mm, 1.63 mm, 1.65 mm, 1.68 mm, 1.7 mm. The tolerance of the length of the first contact area 11 extending from the connection area 101 is ±0.05. Preferably, the length of the first contact area 11 extending from the connection area 101 is 1.6 mm.

[0138] Optionally, the width of the first contact area 11 is 2.4 mm - 2.6 mm. For example, it is 2.4 mm, 2.42 mm, 2.45 mm, 2.5 mm, 2.53 mm, 2.55 mm, 2.58 mm, 2.6 mm. The tolerance of the width of the first contact area 11 is ±0.05. Preferably, the width of the first contact area 11 is 2.5 mm.

[0139] Optionally, the length of the second contact area 12 extending from the connection area 101 is 0.8 mm - 1.1 mm. For example, it is 0.8 mm, 0.82 mm, 0.85 mm, 0.9 mm, 0.95 mm, 1 mm, 1.05 mm, 1.1 mm. The tolerance of the length of the first contact area 11 extending from the connection area 101 is ±0.05. Preferably, the length of the first contact area 11 extending from the connection area 101 is 0.95 mm.

[0140] Optionally, the width of the second contact area 12 is 2.4 mm - 2.6 mm. For example, it is 2.4 mm, 2.42 mm, 2.45 mm, 2.5 mm, 2.53 mm, 2.55 mm, 2.58 mm, 2.6 mm. The tolerance of the width of the second contact area 12 is ±0.05. Preferably, the width of the first contact area 11 is 2.5 mm.

[0141] Please refer to Figure 5 and Figure 6 Optionally, the connection area 101 is provided with a slit 13, and one end of the slit 13 forms an opening in the connection area 101. Thus, since the connection area 101 is provided with the slit 13 and one end of the slit 13 forms an opening in the connection area 101, the deformation of the solder tape 10 can be absorbed through the slit 13, reducing the damage to the battery chip caused by stress.

[0142] It can be understood that when the solder tape 10 is subjected to stress, the slit 13 compresses or expands, so that the telescopic stress can be better absorbed through the deformation of the slit 13.

[0143] It can be understood that the slit 13 is in a long and narrow shape, and one end and the other end of the slit 13 refer to the two ends in the length direction of the slit 13.

[0144] Specifically, in Figure 5 and Figure 6In the example, the gap 13 is rectangular. In this way, the shape of the gap 13 is relatively regular, which is convenient for manufacturing. It can be understood that in other examples, the gap 13 can also be oval, racetrack-shaped, or other irregular shapes.

[0145] Furthermore, when the gap 13 is rectangular and the length direction of the gap 13 coincides with the width direction of the connection area 101, the length of the gap 13 refers to the dimension of the gap 13 in the width direction of the connection area 101. The width of the gap 13 refers to the dimension of the gap 13 in the length direction of the connection area 101.

[0146] Specifically, in Figure 5 and Figure 6 In the example, the number of gaps 13 is multiple. In this way, through the multiple gaps 13, the ability of the solder ribbon 10 to absorb the expansion and contraction stress is stronger, which is beneficial to further reduce the damage of the stress to the battery chip. It can be understood that in other embodiments, the number of gaps 13 can also be one.

[0147] Specifically, in Figure 5 and Figure 6 In the example, the openings of the gaps 13 are formed on both sides in the width direction of the connection area 101. In this way, the connection area 101 can deform on both sides in the width direction through the gaps 13, expanding the deformation range, making the ability of the solder ribbon 10 to absorb the expansion and contraction stress stronger, which is beneficial to further reduce the damage of the stress to the battery chip. It can be understood that in other embodiments, the openings of the gaps 13 can also be formed only on one side in the width direction of the connection area 101; or can be formed on one side or both sides in the length direction of the connection area 101.

[0148] Please refer to Figure 5 , optionally, each first contact area 11 corresponds to a group of gaps 13. As the distance in the length direction from the corresponding first contact area 11 increases, the distance between a group of gaps 13 and the corresponding first contact area 11 in the width direction also increases. Optionally, each second contact area 12 corresponds to a group of gaps 13. As the distance in the length direction from the corresponding second contact area 12 increases, the distance between a group of gaps 13 and the corresponding second contact area 12 in the width direction also increases. In this way, the solder ribbon 10 transmits current better and the effect of the solder ribbon 10 absorbing stress is better.

[0149] Specifically, in Figure 5 In the example, among the group of gaps 13 corresponding to the first contact area 11, the number of gaps 13 is 5, and among the group of gaps 13 corresponding to the second contact area 12, the number of gaps 13 is 5.

[0150] It can be understood that in other embodiments, the number of slits 13 in a set of slits 13 corresponding to the first contact area 11 may also be different from the number of slits 13 in a set of slits 13 corresponding to the second contact area 12; the number of slits 13 in a set of slits 13 corresponding to the first contact area 11 may be 2, 3, 4, 6 or other numbers; the number of slits 13 in a set of slits 13 corresponding to the second contact area 12 may be 2, 3, 4, 6 or other numbers.

[0151] It can be understood that in other embodiments, each first contact area 11 may also correspond to a set of slits 13. As the distance from the corresponding first contact area 11 in the length direction increases, the distance between a set of slits 13 and the corresponding first contact area 11 in the width direction decreases. In other embodiments, each second contact area 12 may also correspond to a set of slits 13. As the distance from the corresponding second contact area 12 in the length direction increases, the distance between a set of slits 13 and the corresponding second contact area 12 in the width direction decreases. In this way, the current transmission of the solder strip 10 can be better, and the effect of the solder strip 10 absorbing stress can be better.

[0152] Please refer to Figure 5 , optionally, when the number of slits 13 in a set of slits 13 corresponding to the first contact area 11 is odd, a set of slits 13 is symmetric about the center line of the middle slit 13. In this way, a set of slits 13 is arranged symmetrically, which is convenient for manufacturing and is also beneficial to better absorb the expansion and contraction stress through the deformation of the solder strip 10.

[0153] Please note that the center line of the slit 13 is a line passing through the center of the slit 13 and parallel to the width direction.

[0154] Furthermore, the center line of the middle slit 13 coincides with the center line 111 of the corresponding first contact area. In this way, it is convenient to locate the middle slit 13 according to the first contact area 11, or to locate the first contact area 11 according to the middle slit 13, which is beneficial to improving production efficiency.

[0155] Similarly, when the number of slits 13 in a set of slits 13 corresponding to the second contact area 12 is odd, a set of slits 13 is symmetric about the center line of the middle slit 13. In this way, a set of slits 13 is arranged symmetrically, which is convenient for manufacturing and is also beneficial to better absorb the expansion and contraction stress through the deformation of the solder strip 10.

[0156] Furthermore, the center line of the middle slit 13 coincides with the center line of the corresponding second contact area 12. In this way, it is convenient to locate the middle slit 13 according to the second contact area 12, or to locate the second contact area 12 according to the middle slit 13, which is beneficial to improving production efficiency.

[0157] Please refer to Figure 6, optionally, the distances between a set of slits 13 corresponding to the first contact area 11 in the width direction may be equal, and the distances in the length direction may also be equal. In this way, it is convenient for manufacturing and helps improve production efficiency.

[0158] Specifically, in the Figure 6 example, among a set of slits 13 corresponding to the first contact area 11, the number of slits 13 is 2, and they are symmetric about the center line 111 of the first contact area; among a set of slits 13 corresponding to the second contact area 12, the number of slits 13 is 2, and they are symmetric about the center line 121 of the second contact area 12.

[0159] Please refer to Figure 6 , optionally, when the number of slits 13 in a set of slits 13 corresponding to the first contact area 11 is even, the set of slits 13 is symmetric about the center line of the two middle slits 13. In this way, the set of slits 13 is arranged symmetrically, which is convenient for manufacturing and also helps better absorb the expansion and contraction stress through the deformation of the solder strip 10.

[0160] Please note that the center line of the two middle slits 13 is a line passing through the midpoints of the two middle slits 13 and parallel to the width direction.

[0161] Furthermore, the center line of the two middle slits 13 coincides with the center line 111 of the corresponding first contact area. In this way, it is convenient to locate the two middle slits 13 according to the first contact area 11, or to locate the first contact area 11 according to the two middle slits 13, which helps improve production efficiency.

[0162] Similarly, when the number of slits 13 in a set of slits 13 corresponding to the second contact area 12 is even, the set of slits 13 is symmetric about the center line of the two middle slits 13. In this way, the set of slits 13 is arranged symmetrically, which is convenient for manufacturing and also helps better absorb the expansion and contraction stress through the deformation of the solder strip 10.

[0163] Furthermore, the center line of the two middle slits 13 coincides with the center line of the corresponding second contact area 12. In this way, it is convenient to locate the two middle slits 13 according to the second contact area 12, or to locate the second contact area 12 according to the two middle slits 13, which helps improve production efficiency.

[0164] Please refer to Figure 7, optionally, a set of slits 13 includes a first slit 131, a second slit 132, a third slit 133, a fourth slit 134, and a fifth slit 135. The first slit 131 is located at the middle position of the set of slits 13, and the second slit 132 and the third slit 133 are respectively located on both sides of the first slit 131; the fourth slit 134 is located on the side of the second slit 132 away from the first slit 131, and the fifth slit 135 is located on the side of the third slit 133 away from the first slit 131; the lengths of the set of slits 13 satisfy the following relationship:

[0165] L1>L2 = L3>L4 = L5;

[0166] wherein, L1 is the length of the first slit 131, L2 is the length of the second slit 132, L3 is the length of the third slit 133, L4 is the length of the fourth slit 134, and L5 is the length of the fifth slit 135.

[0167] In this way, as the distances between the five slits 13 and the corresponding solder joints increase in the length direction, the distances between the five slits 13 and the corresponding solder joints also increase in the width direction, and at the same time, the lengths of the five slits 13 are symmetric about the first slit 131 located in the middle, which is beneficial to better absorb the expansion and contraction stress through the deformation of the solder strip 10.

[0168] Please refer to Figure 7 , optionally, the length L1 of the first slit 131 is 1.75 mm - 1.85 mm. For example, it is 1.75 mm, 1.8 mm, 1.82 mm, 1.83 mm, 1.84 mm, 1.85 mm. Preferably, the length L1 of the first slit 131 is 1.8 mm.

[0169] Optionally, the length L2 of the second slit 132 is 1.5 mm - 1.7 mm. For example, it is 1.5 mm, 1.55 mm, 1.58 mm, 1.6 mm, 1.65 mm, 1.7 mm. Preferably, the length L2 of the second slit 132 is 1.6 mm.

[0170] Optionally, the length L3 of the third slit 133 is 1.5 mm - 1.7 mm. For example, it is 1.5 mm, 1.55 mm, 1.58 mm, 1.6 mm, 1.65 mm, 1.7 mm. Preferably, the length L3 of the third slit 133 is 1.6 mm.

[0171] Optionally, the length L4 of the fourth slit 134 is 0.6 mm - 0.8 mm. For example, it is 0.6 mm, 0.65 mm, 0.68 mm, 0.7 mm, 0.75 mm, 0.8 mm. Preferably, the length L4 of the fourth slit 134 is 0.7 mm.

[0172] Optionally, the length L5 of the fifth gap 135 is 0.6 mm - 0.8 mm. For example, it can be 0.6 mm, 0.65 mm, 0.68 mm, 0.7 mm, 0.75 mm, or 0.8 mm. Preferably, the length L5 of the fifth gap 135 is 0.7 mm.

[0173] Please refer to Figure 7 , optionally, the solder strip 10 connects the first solar cell 21 and the second solar cell 22. The connection area 101 includes a first connection portion 1011 covering the first solar cell 21, a second connection portion 1012 covering the second solar cell 22, and a third connection portion 1013 covering the gap between the first solar cell 21 and the second solar cell 22; the dimensions of the solder strip 10 satisfy the following relationship:

[0174] d1 = L2, and / or, d1 = L3;

[0175] wherein, d1 is the width of the first connection portion 1011, L2 is the length of the second gap 132, and L3 is the length of the third gap 133.

[0176] In this way, the length of the second gap 132 and / or the third gap 133 is equal to the width of the first connection portion 1011, so that the deformation ability of the part of the connection area 101 in contact with the solar cell is stronger, and the ability to absorb telescopic stress is stronger, which can further reduce the damage of stress to the solar cell.

[0177] Please refer to Figure 7 , optionally, the distance between two adjacent gaps 13 in a group of gaps 13 satisfies the following relationship:

[0178] 0.2 < L1 / (S1 + S2) < 1.5;

[0179] wherein, L1 is the length of the first gap 131, S1 is the distance between the first gap 131 and the second gap 132, and S2 is the distance between the second gap 132 and the fourth gap 134;

[0180] and / or, 0.2 < L1 / (S3 + S4) < 1.5;

[0181] wherein, L1 is the length of the first gap 131, S3 is the distance between the first gap 131 and the third gap 133, and S4 is the distance between the third gap 133 and the fifth gap 135.

[0182] In this way, the distance between two adjacent gaps 13 in a group of gaps 13 is related to the length of the first gap 131, so as to better absorb telescopic stress and further minimize the damage of stress to the solar cell.

[0183] Specifically, the value of L1:(S3 + S4) is, for example, 0.21, 0.22, 0.37, 0.8, 0.9, 1, 1.3, 1.49.

[0184] In Figure 7 the example of, the value of L1:(S3 + S4) is 0.37. L1 is 1.8 mm, S3 is 2.9 mm, and S4 is 2 mm.

[0185] Please refer to Figure 7 , optionally, the width d1 of the first connecting portion 1011 is 1.5 mm - 1.7 mm. For example, it is 1.5 mm, 1.55 mm, 1.58 mm, 1.6 mm, 1.65 mm, 1.7 mm. Preferably, the width d1 of the first connecting portion 1011 is 1.6 mm.

[0186] Optionally, the width d2 of the second connecting portion 1012 is 1.5 mm - 1.7 mm. For example, it is 1.5 mm, 1.55 mm, 1.58 mm, 1.6 mm, 1.65 mm, 1.7 mm. Preferably, the width d2 of the second connecting portion 1012 is 1.6 mm.

[0187] Optionally, the width d3 of the third connecting portion 1013 is 0.1 mm - 2 mm. For example, it is 0.1 mm, 0.12 mm, 0.15 mm, 0.18 mm, 0.2 mm, 0.8 mm, 1 mm, 1.5 mm, 1.7, 2 mm. Preferably, the width d3 of the third connecting portion 1013 is 0.15 mm.

[0188] Optionally, the solder strip 10 connects the first solar cell 21 and the second solar cell 22. The first contact area 11 connects to the positive electrode of the first solar cell 21, and the second contact area 12 connects to the negative electrode of the second solar cell 22, and the area of the first contact area 11 is greater than or equal to the area of the second contact area 12; or, the first contact area 11 connects to the negative electrode of the first solar cell 21, and the second contact area 12 connects to the positive electrode of the second solar cell 22, and the area of the second contact area 12 is greater than or equal to the area of the first contact area 11.

[0189] It can be understood that since the current of the positive electrode is larger than that of the negative electrode, thus the width of the connecting portion corresponding to the positive electrode can be made larger, making the structure of the solder strip more matched with the current of the solar cell.

[0190] Specifically, the area of the first contact area 11 is greater than or equal to the area of the second contact area 12. It can be that the widths of the first contact area 11 and the second contact area 12 are the same, and the length of the first contact area 11 is greater than the length of the second contact area 12; it can also be that the lengths of the first contact area 11 and the second contact area 12 are the same, and the width of the first contact area 11 is greater than the width of the second contact area 12; or it can be that the length of the first contact area 11 is greater than the length of the second contact area 12, and the width of the first contact area 11 is greater than the width of the second contact area 12.

[0191] Please refer to Figure 7 , optionally, the number of the slits 13 is multiple, and the extending directions of the multiple slits 13 are all parallel to the width direction of the connecting area 101. In this way, the telescopic stress in the length direction of the connecting area 101 can be absorbed more, and the damage to the battery sheet caused by the stress can be reduced. Moreover, this makes the extending directions of the multiple slits 13 parallel to each other, which is convenient for manufacturing and is beneficial to improving the production efficiency.

[0192] It can be understood that in other embodiments, the extending directions of all the slits 13 can be at an angle to the width direction of the connecting area 101; the extending directions of some of the slits 13 can be at an angle to the width direction of the connecting area 101, and the extending directions of the remaining slits 13 are parallel to the width direction of the connecting area 101. Further, when the extending directions of the multiple slits 13 are at an angle to the width direction of the connecting area 101, the multiple slits 13 can be parallel to each other or not parallel to each other.

[0193] Please refer to Figure 7 , optionally, the width w1 of the slit 13 is 0.2 mm - 0.6 mm. For example, it is 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm. In this way, the width w1 of the slit 13 is within a suitable range, avoiding poor deformation ability of the welding tape 10 caused by too small width w1 of the slit 13, and avoiding poor strength of the welding tape 10 caused by too large width w1 of the slit 13. The tolerance of the width w1 of the slit 13 can be ±0.05.

[0194] Preferably, the width w1 of the slit 13 is 0.4 mm. In this way, the deformation ability and mechanical strength of the welding tape 10 can be taken into account, and the overall effect is the best.

[0195] Specifically, in the Figure 7 example, the width w1 of the slit 13 is the dimension of the slit 13 in the length direction of the connecting area 101.

[0196] Please refer to Figure 7, optionally, in the same group of slits 13, the distance between two adjacent slits 13 is 1.5 mm - 4 mm. For example, it can be 1.5 mm, 1.8 mm, 1.9 mm, 2.0 mm, 2.5 mm, 2.9 mm, 3 mm, 3.5 mm, 4 mm. In this way, the distance between two adjacent slits 13 is within a suitable range, avoiding poor mechanical strength of the solder strip 10 caused by too small a distance between two adjacent slits 13, and also avoiding poor deformation ability of the solder strip 10 caused by too large a distance between two adjacent slits 13.

[0197] Specifically, the distance between two adjacent slits 13 refers to the distance between the center lines of two adjacent slits 13. As Figure 7 shown in, S1 in is the distance between the first slit 131 and the second slit 132, which is 2.9 mm; S2 is the distance between the second slit 132 and the fourth slit 134, which is 2 mm; S3 is the distance between the first slit 131 and the third slit 133, which is 2.9 mm; S4 is the distance between the third slit 133 and the fifth slit 135, which is 2 mm. The tolerance is ±0.01.

[0198] Specifically, in a group of slits 13, the distance between two adjacent slits 13 can be the same or different. When the distance between two adjacent slits 13 is the same, the distance between two adjacent slits 13 is a fixed value within the range of 1.5 mm - 4 mm; when the distance between two adjacent slits 13 is different, the distance between two adjacent slits 13 is multiple values within the range of 1.5 mm - 4 mm.

[0199] Please refer to Figure 7 , optionally, the distance D1 between two adjacent groups of slits 13 is 1.5 mm - 15 mm. For example, it can be 1.5 mm, 1.575 mm, 2 mm, 5 mm, 8 mm, 10 mm, 12 mm, 15 mm. In this way, the distance D1 between two adjacent groups of slits 13 is within a suitable range, avoiding poor mechanical strength of the solder strip 10 caused by too small a distance D1 between two adjacent groups of slits 13, and also avoiding poor deformation ability of the solder strip 10 caused by too large a distance D1 between two adjacent groups of slits 13. Preferably, the distance D1 between two adjacent groups of slits 13 is 1.575 mm.

[0200] Specifically, the distance between two adjacent groups of slits 13 refers to the distance between the two slits 13 that belong to two groups of slits 13 respectively and are the closest to each other.

[0201] Please refer to Figure 8 , optionally, the connection area 101 is further provided with a through hole 14, and the other end of the slit 13 is communicated with the through hole 14. In this way, the deformation of the solder strip 10 can be absorbed through the through hole 14, reducing the damage to the battery cell caused by stress. Moreover, the slit 13 is communicated with the through hole 14, making the effect of absorbing the deformation of the solder strip 10 better.

[0202] Specifically, the number of the through holes 14 can be one or more. One slit 13 can communicate with one through hole 14, multiple slits 13 can communicate with one through hole 14, and one slit 13 can communicate with multiple through holes 14. The specific manner in which the slit 13 communicates with the through hole 14 is not limited herein.

[0203] Please refer to Figure 8 , for the through holes 14 corresponding to the second slit 132 and the third slit 133, they are oval-shaped, and the length of the minor axis is greater than the width of the gap between the first battery cell 21 and the second battery cell 22. The through holes 14 corresponding to the second slit 132 and the third slit 133 are misaligned with the gap between the first battery cell 21 and the second battery cell 22.

[0204] Please refer to Figure 8 , optionally, the major axis of the through hole 14 corresponding to the first slit 131 is 2.3 mm - 2.5 mm. For example, it is 2.3 mm, 2.32 mm, 2.38 mm, 2.4 mm, 2.45 mm, 2.5 mm. Preferably, the major axis of the through hole 14 corresponding to the first slit 131 is 2.4 mm.

[0205] Please refer to Figure 8 , optionally, the minor axis of the through hole 14 corresponding to the first slit 131 is 0.9 mm - 1.1 mm. For example, it is 0.9 mm, 0.92 mm, 0.95 mm, 1 mm, 1.05 mm, 1.1 mm. Preferably, the minor axis of the through hole 14 corresponding to the first slit 131 is 1 mm.

[0206] Please refer to Figure 8 , optionally, the major axis of the through hole 14 corresponding to the second slit 132 is 1.9 mm - 2.1 mm. For example, it is 1.9 mm, 1.92 mm, 1.95 mm, 2 mm, 2.05 mm, 2.07 mm, 2.1 mm. Preferably, the major axis of the through hole 14 corresponding to the second slit 132 is 2 mm.

[0207] Please refer to Figure 8 , optionally, the minor axis of the through hole 14 corresponding to the second slit 132 is 0.75 mm - 0.85 mm. For example, it is 0.75 mm, 0.76 mm, 0.78 mm, 0.8 mm, 0.81 mm, 0.84 mm, 0.85 mm. Preferably, the minor axis of the through hole 14 corresponding to the second slit 132 is 0.8 mm.

[0208] Please refer to Figure 8 , optionally, the major axis of the through hole 14 corresponding to the third slit 133 is 1.9 mm - 2.1 mm. For example, it is 1.9 mm, 1.92 mm, 1.95 mm, 2 mm, 2.05 mm, 2.07 mm, 2.1 mm. Preferably, the major axis of the through hole 14 corresponding to the third slit 133 is 2 mm.

[0209] Please refer to Figure 8 . Optionally, the minor axis of the through hole 14 corresponding to the third slit 133 is 0.75 mm - 0.85 mm. For example, it is 0.75 mm, 0.76 mm, 0.78 mm, 0.8 mm, 0.81 mm, 0.84 mm, 0.85 mm. Preferably, the minor axis of the through hole 14 corresponding to the third slit 133 is 0.8 mm.

[0210] Please refer to Figure 8 ... Optionally, the major axis of the through hole 14 corresponding to the fourth slit 134 is 1.1 mm - 1.3 mm. For example, it is 1.1 mm, 1.11 mm, 1.14 mm, 1.2 mm, 1.25 mm, 1.27 mm, 1.3 mm. Preferably, the major axis of the through hole 14 corresponding to the fourth slit 134 is 1.2 mm.

[0211] Please refer to Figure 8 ... Optionally, the minor axis of the through hole 14 corresponding to the fourth slit 134 is 0.5 mm - 0.7 mm. For example, it is 0.5 mm, 0.51 mm, 0.58 mm, 0.6 mm, 0.64 mm, 0.68 mm, 0.7 mm. Preferably, the minor axis of the through hole 14 corresponding to the fourth slit 134 is 0.6 mm.

[0212] Please refer to Figure 8 ... Optionally, the major axis of the through hole 14 corresponding to the fifth slit 135 is 1.1 mm - 1.3 mm. For example, it is 1.1 mm, 1.11 mm, 1.14 mm, 1.2 mm, 1.25 mm, 1.27 mm, 1.3 mm. Preferably, the major axis of the through hole 14 corresponding to the fifth slit 135 is 1.2 mm.

[0213] Please refer to Figure 8 ... Optionally, the minor axis of the through hole 14 corresponding to the fifth slit 135 is 0.5 mm - 0.7 mm. For example, it is 0.5 mm, 0.51 mm, 0.58 mm, 0.6 mm, 0.64 mm, 0.68 mm, 0.7 mm. Preferably, the minor axis of the through hole 14 corresponding to the fifth slit 135 is 0.6 mm.

[0214] Please refer to Figure 8 ... Optionally, four fillets are formed at the connection between the first slit 131 and the corresponding through hole 14, and the radius of each fillet is 0.2.

[0215] Please refer to Figure 8 ... Optionally, four fillets are formed at the connection between the second slit 132 and the corresponding through hole 14, and the radius of each fillet is 0.2.

[0216] Please refer to Figure 8, optionally, four fillets are formed at the connection between the third slit 133 and the corresponding through-hole 14, and the radius of each fillet is 0.2.

[0217] Please refer to Figure 8 , optionally, four fillets are formed at the connection between the fourth slit 134 and the corresponding through-hole 14, and the radius of each fillet is 0.1.

[0218] Please refer to Figure 8 , optionally, four fillets are formed at the connection between the fifth slit 135 and the corresponding through-hole 14, and the radius of each fillet is 0.1.

[0219] Please refer to Figure 9 , optionally, the first contact area 11 is connected to the first solar cell 21, the second contact area 12 is connected to the second solar cell 22, the through-hole 14 is elliptical, the short axis length of the through-hole 14 is the width of the gap between the first solar cell 21 and the second solar cell 22, and the long axis of the through-hole 14 coincides with the center line 1001 of the connection area 101.

[0220] In this way, the short axis of the through-hole 14 is stuck between the first solar cell 21 and the second solar cell 22 and is parallel to the width direction of the connection area 101, and the long axis of the through-hole 14 is parallel to the length direction of the connection area 101, so that the through-hole 14 has a better effect of absorbing the deformation of the solder tape 10, and the damage to the solar cells caused by stress can be further reduced.

[0221] Specifically, the long axis of the through-hole 14 coincides with the center line of the gap between the first solar cell 21 and the second solar cell 22. In this way, the through-hole 14 has a better effect of absorbing the deformation of the solder tape 10, and the damage to the solar cells caused by stress can be further reduced.

[0222] Specifically, in Figure 9 the example, among the through-holes 14 corresponding to a group of slits 13, the through-holes 14 corresponding to the second slit 132 and the third slit 133 are elliptical, the short axis length is the width of the gap between the first solar cell 21 and the second solar cell 22, and the long axis coincides with the center line 1001 of the connection area 101. In this way, through the through-holes 14 corresponding to the first slit 131, the fourth slit 134 and the fifth slit 135, the deformation of the solder tape 10 is absorbed at other positions of the connection area 101, so that the effect of absorbing deformation is better.

[0223] It can be understood that in other examples, all the through-holes 14 corresponding to a group of slits 13 may also be elliptical, the short axis lengths are all the width of the gap between the first solar cell 21 and the second solar cell 22, and the long axes coincide with the center line 1001 of the connection area 101.

[0224] It can be understood that in other examples, in addition to being oval, the through holes 14 can also be circular, semi-circular, diamond-shaped or other shapes. The shapes of the plurality of through holes 14 can be the same or different. This is not limited herein.

[0225] Optionally, in a group of through holes 14 corresponding to each first contact area 11, two adjacent through holes 14 are staggered in the length direction. In this way, current can be transmitted better, and the deformation of the welding strip 10 can be absorbed better.

[0226] It can be understood that in other embodiments, in a group of through holes 14 corresponding to each first contact area 11, two adjacent through holes 14 can be partially overlapped or completely overlapped in the length direction.

[0227] Please refer to Figure 8 and Figure 9 , optionally, each first contact area 11 corresponds to a group of through holes 14. As the distance in the length direction from the corresponding first contact area 11 increases, both the major axis and the minor axis of a group of through holes 14 decrease. Optionally, each second contact area 12 corresponds to a group of through holes 14. As the distance in the length direction from the corresponding second contact area 12 increases, both the major axis and the minor axis of a group of through holes 14 decrease. In this way, the welding strip 10 can transmit current better, and the effect of the welding strip 10 absorbing stress is better.

[0228] It can be understood that in other embodiments, each first contact area 11 can also correspond to a group of through holes 14. As the distance in the length direction from the corresponding first contact area 11 increases, both the major axis and the minor axis of a group of through holes 14 increase. In other embodiments, each second contact area 12 can also correspond to a group of through holes 14. As the distance in the length direction from the corresponding second contact area 12 increases, both the major axis and the minor axis of a group of through holes 14 increase.

[0229] Please refer to Figure 9 , optionally, the distance between two adjacent gaps 13 in a group of gaps 13 is equal.

[0230] It can be understood that in a group of gaps 13, the distances between two adjacent gaps 13 can all be different; or some can be the same and some can be different.

[0231] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A battery string, characterized in that, Comprising: At least two solar cells, each of the solar cells including a first electrode and a second electrode having a polarity opposite to that of the first electrode; And A solder ribbon respectively connecting a first solar cell and a second solar cell adjacent to the first solar cell, the solder ribbon including a first contact area, a second contact area and a connection area; The first contact area is for connecting the first solar cell, the second contact area is for connecting the second solar cell, and the connection area is for connecting the first contact area and the second contact area; The center lines of at least one group of adjacent first contact areas and second contact areas are offset in the width direction of the connection area; The connection area is provided with a slit, and one end of the slit forms an opening in the connection area; Each first contact area corresponds to a group of the slits, and as the distance in the length direction from the corresponding first contact area increases, the distance in the width direction between a group of the slits and the corresponding first contact area also increases; and / or, each second contact area corresponds to a group of the slits, and as the distance in the length direction from the corresponding second contact area increases, the distance in the width direction between a group of the slits and the corresponding second contact area also increases; The thickness of the solder ribbon is 0.1 mm - 0.3 mm.

2. The battery string according to claim 1, wherein The first solar cell is provided with a first pad point and a second pad point, the first pad point connecting the first electrode of the first solar cell, and the second pad point connecting the second electrode of the first solar cell; the line connecting the first pad point and the second pad point closest to the first pad point forms a first angle with the length direction of the solder ribbon; The second solar cell is provided with a third pad point and a fourth pad point, the third pad point connecting the third electrode of the second solar cell, and the fourth pad point connecting the fourth electrode of the second solar cell; the line connecting the third pad point and the fourth pad point closest to the third pad point forms a second angle with the length direction of the solder ribbon.

3. The battery string according to claim 2, characterized in that, 70°<α<90°,70°<β<90°； Wherein, α is the first angle and β is the second angle.

4. The battery string according to claim 1, wherein, The first solar cell is provided with a first pad point and a second pad point, the first pad point connecting the first electrode of the first solar cell, and the second pad point connecting the second electrode of the first solar cell; the second solar cell is provided with a third pad point and a fourth pad point, the third pad point connecting the third electrode of the second solar cell, and the fourth pad point connecting the fourth electrode of the second solar cell; The solder ribbon connects the first pad point and the fourth pad point, and the line connecting the first pad point and the fourth pad point closest to the first pad point forms a third angle with the length direction of the solder ribbon.

5. The battery string according to claim 4, characterized in that, 20° < γ < 60°; Wherein, γ is the third angle.

6. The battery string according to claim 1, wherein A group of the slits includes a first slit, a second slit, a third slit, a fourth slit and a fifth slit, the first slit being located at the middle position of the group of the slits, and the second slit and the third slit being respectively located on both sides of the first slit; The fourth slit is located on a side of the second slit facing away from the first slit, and the fifth slit is located on a side of the third slit facing away from the first slit; The lengths of a set of the slits satisfy the following relationship: L1>L2=L3>L4=L5; Among them, L1 is the length of the first gap, L2 is the length of the second gap, L3 is the length of the third gap, L4 is the length of the fourth gap, and L5 is the length of the fifth gap.

7. The battery string according to claim 6, characterized in that, The welding ribbon connects the first battery cell and the second battery cell, and the connection area includes a first connection portion covering the first battery cell, a second connection portion covering the second battery cell, and a third connection portion covering the gap between the first battery cell and the second battery cell; The size of the welding strip satisfies the following relationship: d1=L2, and / or, d1=L3; Wherein, d1 is the width of the first connecting portion, L2 is the length of the second gap, and L3 is the length of the third gap.

8. The battery string according to claim 6, wherein The distance between two adjacent gaps in a group of gaps satisfies the following relationship: 0.2 <L1 / (S1+S2)<1.5; Wherein, L1 is the length of the first gap, S1 is the distance between the first gap and the second gap, and S2 is the distance between the second gap and the fourth gap; and / or, 0.2 <L1 / (S3+S4)<1.5; Wherein, L1 is the length of the first gap, S3 is the distance between the first gap and the third gap, and S4 is the distance between the third gap and the fifth gap.

9. The battery string according to claim 1, wherein Each first contact area corresponds to a group of the slits, and as the distance from the corresponding first contact area in the length direction increases, the distance between the group of the slits and the corresponding first contact area in the width direction decreases; And / or, each second contact area corresponds to a group of the slits, and as the distance from the corresponding second contact area in the length direction increases, the distance between a group of the slits and the corresponding second contact area in the width direction decreases.

10. The battery string according to claim 1, characterized in that, Each of the first contact areas corresponds to a group of the gaps, and the distance between two adjacent gaps in a group of the gaps is equal; And / or, each of the second contact areas corresponds to a group of the gaps, and the distance between two adjacent gaps in a group of the gaps is equal.

11. The battery string according to claim 1, wherein There are multiple slits, and the extension directions of the multiple slits are parallel to the width direction of the connection area.

12. The battery string according to claim 1, characterized in that, The width of the gap is 0.2mm-0.6mm.

13. The battery string according to claim 1, characterized in that, In the same group of the slits, the distance between two adjacent slits is 1.5mm-4mm.

14. The battery string according to claim 1, characterized in that, The distance between two adjacent groups of gaps is 1.5mm-15mm.

15. The battery string according to any one of claims 1-14, characterized in that, The connection area is further provided with a through hole, and the other end of the gap is connected to the through hole.

16. The battery string according to claim 15, wherein, The first contact area is connected to the first battery cell, the second contact area is connected to the second battery cell, the through hole is elliptical, the short axis length of the through hole is the width of the gap between the first battery cell and the second battery cell, and the long axis of the through hole coincides with the center line of the connection area.

17. The battery string according to claim 15, characterized in that, The through hole is in the shape of an ellipse, a perfect circle, a semicircle or a diamond.

18. The battery string according to claim 15, characterized in that, In a group of through holes corresponding to each of the first contact regions, two adjacent through holes are staggered in the length direction.

19. The battery string according to claim 1, characterized in that, The solder strip connects the first solar cell and the second solar cell. The first contact region connects the positive electrode of the first solar cell, and the second contact region connects the negative electrode of the second solar cell, and the area of the first contact region is greater than or equal to the area of the second contact region; or, the first contact region connects the negative electrode of the first solar cell, the second contact region connects the positive electrode of the second solar cell, and the area of the second contact region is greater than or equal to the area of the first contact region.

20. The battery string according to claim 1, characterized in that, The width of the connection region is 2.3 mm - 6 mm.

21. The battery string according to claim 1, wherein The distance between the adjacent first contact region and the second contact region in the width direction of the connection region is 5 mm - 15 mm.

22. The battery string according to claim 1, wherein The solder strip includes a copper substrate and a tin layer coated on the copper substrate; or, the solder strip includes an aluminum substrate and a tin layer coated on the aluminum substrate; or, the solder strip is an aluminum strip; or, the solder strip is a tin strip.

23. The battery string according to claim 1, characterized in that, A plurality of the first contact regions are equally spaced along the length direction of the connection region on one side of the connection region; And / or, a plurality of the second contact regions are equally spaced along the length direction of the connection region on the other side of the connection region.

24. The battery string according to claim 1, characterized in that, The connection region is rectangular; or, the connection region is bent, and the first contact region and the second contact region are arranged at the bending angle.

25. The battery string according to claim 1, wherein The first contact region is in the shape of a right-angled rectangle, a rounded rectangle, a perfect circle, a semi-circle, a trapezoid; and / or, the second contact region is in the shape of a right-angled rectangle, a rounded rectangle, a perfect circle, a semi-circle, a trapezoid.

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